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Patent 2192642 Summary

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Claims and Abstract availability

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(12) Patent: (11) CA 2192642
(54) English Title: DRAW TAPE MACHINES AND METHODS
(54) French Title: MACHINES A BANDES DE SERRAGE ET METHODES CONNEXES
Status: Expired
Bibliographic Data
(51) International Patent Classification (IPC):
  • B31B 70/81 (2017.01)
(72) Inventors :
  • SELLE, PAUL A. (United States of America)
  • GIETMAN, PETER J., JR. (United States of America)
  • DUTTER, TIMOTHY R. (United States of America)
  • JANSEN, THOMAS C. (United States of America)
  • SLAMA, FRANK M. (United States of America)
(73) Owners :
  • CMD CORPORATION (United States of America)
(71) Applicants :
  • CMD CORPORATION (United States of America)
(74) Agent: MACRAE & CO.
(74) Associate agent:
(45) Issued: 2006-02-14
(22) Filed Date: 1996-12-11
(41) Open to Public Inspection: 1997-07-03
Examination requested: 2001-10-22
Availability of licence: N/A
(25) Language of filing: English

Patent Cooperation Treaty (PCT): No

(30) Application Priority Data:
Application No. Country/Territory Date
582,069 United States of America 1996-01-02
582,072 United States of America 1996-01-02

Abstracts

English Abstract

This invention pertains to draw tape equipment, and methods for incorporating draw tapes into plastic and like bags. In general, a continuous plastic web is slit at a slitting station to form layers, and respective free edges. The web then passes to a hole forming station where holes are formed in the top and bottom layers adjacent the free edges. After holes are punched, edge regions of the top and bottom layers are separated from each other, followed by forming of hems in the separated layers at hem forming stations arranged in parallel with each other. Concurrent with forming of the hems, continuous draw tapes are fed to the hem forming stations and the hems are formed about the draw tapes. The formed hems, with the draw tapes incorporated therein, optionally pass through transverse stretching apparatus and/or through electrostatic pinning apparatus and/or through first temperature control stations where the temperature of the plastic web is controlled to a desired temperature before hem sealing. The formed hems are then sealed to the main bodies of the respective top and bottom layers. The sealed hems optionally pass through second temperature control stations to cool the web. The edge regions of the layers are then rejoined, in face-to-face relationship with each other.


French Abstract

Cette invention concerne du matériel de bandes à serrage, et des méthodes pour incorporer des bandes à serrage dans des sacs en plastique et similaires. En général, une bande continue en plastique est fendue à une refendeuse pour former des couches, ainsi que des bords respectifs libres. La bande passe ensuite par une station de trous où des trous sont percés dans les couches supérieure et inférieure adjacentes aux bords libres. Une fois les trous percés, les régions de bordure des couches supérieure et inférieure sont séparées l'une de l'autre, puis forment des ourlets sur les couches séparées à des stations d'ourlets disposées en parallèle l'une avec l'autre. En même temps que la formation d'ourlets, des bandes de serrage continues alimentent les stations de formation d'ourlets et les ourlets sont formés autour des bandes de serrage. Les ourlets formés, renfermant les bandes de serrage, passent éventuellement par un appareil d'étirement transversal et/ou par des appareils d'épinglage électrostatiques et/ou par les premières stations de contrôle de température où la température de la bande en plastique est régulée afin d'atteindre la température souhaitée avant de sceller l'ourlet. Les ourlets formés sont ensuite scellés aux parties principales des couches supérieure et inférieure respectives. Les ourlets scellés traversent éventuellement les deuxièmes stations de contrôle de température pour refroidir la bande. Les régions de bordure des couches sont ensuite assemblées, chacune étant dans une relation de face à face avec l'autre.

Claims

Note: Claims are shown in the official language in which they were submitted.



-26-


CLAIMS:

1. A machine for providing a draw tape in a plastic web, the plastic
web having top and bottom layers, the top layer having a first main body
portion, a first top layer edge portion, and first top layer free edge, the
bottom layer having a second main body portion, second bottom layer edge
portion, and second bottom layer free edge; the first and second edge
portions of the top and bottom layers respectively being folded onto
respective first and second main body portions of the top and bottom layers,
to form respective first top layer and second bottom layer hems, with
respective first top layer and second bottom layer draw tapes being
incorporated into the hems, the first and second edge portions being sealed
to the respective main body portions to form first top layer and second
bottom layer sealed hems, with the first top layer and second bottom layer
draw tapes in the respective sealed hems, said machine comprising:
(a) hole forming apparatus forming holes, at spaced locations in the
web, in the edge portions adjacent respective first and second free
edges of the web;
(b) tape unwind apparatus following the hole forming apparatus for
feeding first and second draw tapes into proximity with, and
aligned with, the first and second edge portions;
(c) hem forming apparatus adjacent the tape unwind apparatus for
separating first and second edge regions of the top and bottom
layers from each other, for traverse along parallel but spaced first
and second paths while holding the main body portions of the top




- 27 -

and bottom layers in surface-to-surface contact with each other,
the first and second edge regions including the respective first and
second edge portions and the respective first and second free
edges, said hem forming apparatus for receiving the first and
second draw tapes, and for forming the first and second hems and
incorporating the draw tapes therein; and

(d) hem sealing apparatus downstream from the hem forming
apparatus for sealing the first and second edge portions to the
respective first and second main body portions of the respective
layers, thus sealing the hems and securing the respective draw
tapes therein.

2. The machine as in claim 1, said hem forming apparatus including
first and second hem folding plows having hem folding edges, and a
separating plow adjacent said first hem folding plow, said separating plow
separating the second edge region of the bottom layer from the
corresponding first edge region of the top layer, the separated first and
second edge regions, at corresponding points along the first and second
paths, lying in surfaces intersecting each other along an imaginary line
having a component extending in the direction of travel of the web.

3. The machine as in claim 2, including a separating notch formed by
cooperating elements of said first hem folding plow and said separating
plow, automatically initiating separation of the edge region of the bottom
layer from the edge region of the top layer when the first and second edge
regions traverse transversely across said separating notch.





- 28 -

4. The machine as in claim 2, said hem folding plows having hem
folding edges extending at transverse angles to the direction of travel of the
web.

5. The machine as in claim 4, said hem forming apparatus including
first and second hem forming plows receiving folded edge portions of the
web from said hem folding edges, and folding the folded edge portions back
onto the respective main body portions forming the respective hems.

6. The machine as in claim 1, said hem forming apparatus being
disposed downstream in the processing sequence from said hole forming
apparatus, whereby the edge regions are separated after leaving said hole
forming apparatus.

7. The machine as in claim 1, said hem forming apparatus forming the
first and second hems about the first and second draw tapes.

8. The machine as in claim 1, said hem forming apparatus including
first and second hem folding plows having first and second hem folding
edges extending at first and second transverse angles to the direction of
travel of the web and folding the first and second edge portions of the web,
and first and second hem forming plows having first and second hem
forming edges extending at third and fourth transverse angles to the
direction of travel of the web and receiving the first and second folded edge
portions from said hem folding edges, and folding the folded edge portions
back onto the main body portions, thus forming the first and second hems.

9. The machine as in claim 8, each said hem folding plow having an
aperture therein, the respective draw tape advancing through the respective







- 29 -

aperture in said hem folding plow for forming of the respective hem about
the tape.

10. The machine as in claim 9, the respective draw tapes advancing
between each said hem folding plow and the respective layers.

11. The machine as in claim 8, said first and second hem folding
edges comprising trailing edges of said hem folding plows, said first and
second hem forming edges comprising leading edges of said hem forming
plows.

12. The machine as in claim 8, and wherein each said draw tape
advances over the respective said hem folding plow in contact with the
respective layer of web material in parallel with the folding of the edge
portion of the respective layer by the respective said hem folding plow.

13. The machine as in claim 1, said hem forming apparatus including a
separating plow separating the second edge region of the bottom layer from
the corresponding first edge region of the top layer.

14. The machine as in claim 1, including at least one turning member
downstream of said hem forming apparatus, assisting in returning the edge
regions into face-to-face relationship with each other.

15. The machine as in claim 14, said at least one turning member
comprising an upstanding turning cone.

16. The machine as in claim 1, including a turning member
downstream of said hem forming apparatus, turning portions of the top and







- 30 -

bottom layers, and air lubrication between said turning member and the
bottom layer.

17. A machine for providing a draw tape in a plastic web, the plastic
web having top and bottom layers, the top layer having a first main body
portion, a first top layer edge portion, and first top layer free edge, the
bottom layer having a second main body portion, second bottom layer edge
portion, and second bottom layer free edge; the first top and second bottom
edge portions of the top and bottom layers respectively being folded onto
respective first and second main body portions of the top and bottom layers,
to form respective first top layer and second bottom layer hems, with
respective first top layer and second bottom layer draw tapes being
incorporated into the hems, the first and second edge portions being sealed
to the respective main body portions to form first top layer and second
bottom layer sealed hems, with the first top layer and second bottom layer
draw tapes in the respective sealed hems, said machine comprising:

(a) hole forming apparatus for folding the first and second edge
portions nested together back onto one of the top and bottom main
body portions and forming holes therein, at spaced locations
adjacent respective first and second free edges of the web, then
unfolding the first and second edge portions;

(b) tape unwind apparatus following the hole forming apparatus for
feeding draw tape material into proximity with, and aligned with,
the first and second edge portions;

(c) hem forming apparatus following the tape unwind apparatus for
receiving the draw tape material as first and second draw tapes,







- 31 -

and for receiving the unfolded edge portions of the web, with holes
therein, re-folding the first top and second bottom edge portions,
toward each other and onto first and second ones of the main body
portions of the respective layers, and incorporating the draw tapes
into the hems, thus forming the first and second hems and
incorporating the draw tapes inside; and

(d) hem sealing apparatus downstream from the hem forming
apparatus for sealing the first and second edge portions to the
respective first and second main body portions, thus sealing the
hems and securing the respective draw tapes therein.

18. The machine as in claim 17, said hole forming apparatus receiving
the web with the top layer in overlying contact with the bottom layer, and
folding the first and second edge portions with the first edge portion of the
top layer nested inside the second edge portion of the bottom layer.

19. The machine as in claim 17, said hem forming apparatus forming
the first and second hems about the first and second draw tapes.

20. The machine as in claim 17, said hem forming apparatus including
first and second hem folding plows having first and second hem folding
edges extending at first and second transverse angles to the direction of
travel of the web and folding the first and second edge portions of the web,
and first and second hem forming plows having first and second hem
forming edges extending at third and fourth transverse angles to the
direction of travel of the web and receiving the first and second folded edge
portions from said hem folding edges, and folding the folded edge portions







- 32 -

back onto the respective first and second main body portions, thus forming
the first and second hems.

21. The machine as in claim 20, each said hem folding plow having an
aperture therein, the respective draw tape advancing through the respective
aperture in said hem folding plow for forming of the respective hem about
the tape.

22. The machine as in claim 21, the respective draw tapes advancing
between each said hem folding plow and the respective layers.

23. The machine as in claim 20, said first and second hem folding
edges comprising trailing edges of said hem folding plows, said first and
second hem forming edges comprising leading edges of said hem forming
plows.

24. The machine as in claim 20 wherein each said draw tape
advances over the respective said hem folding plow in contact with the
respective layer of web material in parallel with the folding of the edge
portion of the respective layer by the respective said hem folding plow.

25. The machine as in claim 17, said top and bottom layers
comprising first and second edge regions respectively, said hem forming
apparatus including a separating plow separating the second edge region of
the bottom layer from the corresponding first edge region of the top layer.

26. The machine as in claim 17, including at least one turning member
downstream of said hem forming apparatus, assisting in returning the edge
regions into face-to-face relationship with each other.





- 33 -

27. A machine for providing a draw tape in a plastic web, the plastic
web having top and bottom layers, the top layer having a first main body
portion, a first top layer edge portion, and first top layer free edge, the
bottom layer having a second main body portion, second bottom layer edge
portion, and second bottom layer free edge; the first and second edge
portions of the top and bottom layers respectively being folded onto
respective first and second main body portions of the top and bottom layers,
to form respective first top layer and second bottom layer hems, with
respective first top layer and second bottom layer draw tapes being
incorporated into the hems, the first and second edge portions being sealed
to the respective main body portions to form first top layer and second
bottom layer sealed hems, with the first and second draw tapes in the
respective sealed hems, said machine comprising:

(a) hole forming apparatus for forming holes, at spaced locations in the
first and second edge portions adjacent respective first and second
free edges of the web;

(b) tape unwind apparatus adjacent the hole forming apparatus for
feeding draw tape material into proximity with the first and second
edge portions; and

(c) hem forming and sealing apparatus following the tape unwind
apparatus for receiving the draw tape material as first and second
draw tapes, and for forming the first and second hems,
incorporating the draw tapes into the hems, and sealing the first
and second edge portions to the respective first and second main
body portions of the respective layers using respective first and







- 34 -

second hem sealing elements, thus sealing the hems and securing
the respective draw tapes therein, said hem forming and sealing
apparatus including first and second stretching rollers applying
transverse stretching forces to the respective layers at the first and
second hems, with the draw tapes therein, upstream of the
respective first and second hem sealing elements, while holding the
main body portions of the top and bottom layers in surface-to-
surface contact with each other.

28. The machine as in claim 27, said hem forming and sealing
apparatus being disposed downstream in the processing sequence from said
hole forming apparatus.

29. The machine as in claim 27, said hem forming apparatus forming
the first and second hems about the first and second draw tapes.

30. The machine as in claim 27, said hem forming and sealing
apparatus including first and second hem folding plows having first and
second hem folding edges extending at first and second transverse angles to
the direction of travel of the web and folding the first and second edge
portions of the web, and first and second hem forming plows having first
and second hem forming edges extending at third and fourth transverse
angles to the direction of travel of the web and receiving the first and
second
folded edge portions from said hem folding edges, and folding the folded
edge portions back onto the respective first and second main body portions,
thus forming the first and second hems.

31. The machine as in claim 30, each said hem folding plow having an
aperture therein, the respective draw tape advancing through the respective







- 35 -

aperture in said hem folding plow for forming of the respective hem about
the tape.

32. The machine as in claim 27, and wherein each said draw tape
advances over the respective said hem folding plow in contact with the
respective layer of web material in parallel with the folding of the edge
portion of the respective layer by the respective said hem folding plow.

33. The machine as in claim 27, said hem forming and sealing
apparatus including a separating plow separating the second edge region of
the bottom layer from the corresponding first edge region of the top layer.

34. A machine for providing a draw tape in a plastic web, the plastic
web having top and bottom layers, the top layer having a first main body
portion, a first top layer edge portion, and first top layer free edge, the
second bottom layer having a second main body portion, second bottom
layer edge portion, and second bottom layer free edge; the first and second
edge portions of the top and bottom layers respectively being folded onto
respective first and second main body portions of the top and bottom layers,
to form respective first top layer and second bottom layer hems, with
respective first top layer and second bottom layer draw tapes being
incorporated into the hems, the first and second edge portions being sealed
to the respective main body portions to form first top layer and second
bottom layer sealed hems, with the first and second draw tapes in the
respective sealed hems, said machine comprising:

(a) hole forming apparatus for forming holes, at spaced locations in the
edge portions adjacent respective first and second free edges of
the web;





- 36 -

(b) tape unwind apparatus downstream from the hole forming
apparatus for feeding draw tape material into proximity with the
first and second edge portions;

(c) hem forming and sealing apparatus, adjacent the hole forming
apparatus for separating one of first and second edge regions of
the top and bottom layers from the other of the first and second
edge regions, turning the plane of the second edge region through
a dihedral angle of at least 30 degrees with respect to the plane of
the first edge region while holding the main body portions of the
top and bottom layers in surface-to-surface contact with each
other, receiving the draw tape material as first and second draw
tapes at the respective edge regions, forming the first and second
hems and incorporating the draw tape material into the hems, said
hem sealing apparatus sealing the first and second edge portions to
the respective first and second main body portions of the
respective layers, thus sealing the hems and securing the draw
tapes in the respective sealed hems while the first and second edge
regions are separated; and

(d) a turning member comprising an upstanding turning cone disposed
downstream of said hem forming and sealing apparatus, for
assisting in returning the separated one of the edge regions into
face-to-face relationship with the other of the edge regions.

35. The machine as in claim 34, separating the first and second edge
regions at an angle of from 30 degrees to about 160 degrees.







- 37 -

36. The machine as in claim 34, including a second turning member
downstream of said turning cone, the returning of the separated one of the
edge regions into face-to-face relationship with the other of the edge regions
being effected first by said turning cone.

37. The machine as in claim 34, said hem forming and sealing
apparatus maintaining the other of the first and second edge regions as a
generally straight line extension of the main body portion of the respective
layer.

38. A machine for providing a draw tape in a plastic web, the plastic
web having top and bottom layers, the top layer having a first main body
portion, a first top layer edge portion, and first top layer free edge, the
bottom layer having a second main body portion, second bottom layer edge
portion, and second bottom layer free edge; the first and second edge
portions of the top and bottom layers respectively being folded onto
respective first and second main body portions of the top and bottom layers,
to form respective first top layer and second bottom layer hems, with
respective first top layer and second bottom layer draw tapes being
incorporated into the hems, the first and second edge portions being sealed
to the respective main body portions to form first top layer and second
bottom layer sealed hems, with the first and second draw tapes in the
respective sealed hems, said machine comprising:

(a) hole forming apparatus forming holes, at spaced locations in the
edge portions adjacent respective first and second free edges of
the web;




- 38 -

(b) a plow downstream from the hole forming apparatus for separating
the first and second edge portions and turning the plane of the
bottom edge portion through a dihedral angle with respect to the
plane of the top edge portion,

(c) tape unwind apparatus following the separating plow for feeding
first and second draw tapes into proximity with the first and
second separated edge portions; and

(d) hem forming and sealing apparatus following the tape unwind
apparatus for receiving the draw tapes, forming the first and
second hems, incorporating the draw tapes in the hems, and
sealing the first and second separated edge portions to the
respective first and second main body portions of the respective
layers using respective first and second hem sealing elements, thus
sealing the first and second hems and securing the respective draw
tapes therein, said hem forming and sealing apparatus including an
electrostatic pinning device pinning a formed hem, with draw tape
therein, to an underlying support, and thereby controlling
transverse positioning of the formed hem with respect to said
machine as the hem traverses from the hem forming to the hem
sealing apparatus.

39. The machine as in claim 38, said top and bottom layers
comprising first and second edge regions respectively, said hem forming and
sealing apparatus including a separating plow separating the second edge
region of the bottom layer from the corresponding first edge region of the
top layer.





- 39 -

40. A machine for providing a draw tape in a plastic web, the plastic
web having top and bottom layers, the top layer having a first main body
portion, and a first top layer edge portion, the bottom layer having a second
main body portion, and second bottom layer edge portion; the first top layer
and second bottom layer edge portions of the top and bottom layers
respectively being folded onto respective first and second main body
portions of the top and bottom layers, to form respective first and second
hems, with respective first top layer and second bottom layer draw tapes
being incorporated into the hems, the first and second edge portions being
sealed to the respective main body portions to form first and second sealed
hems, with the first top layer and second bottom layer draw tapes in the
respective sealed hems, said machine comprising:

(a) tape unwind apparatus for feeding draw tape material into
proximity with the first and second edge portions;

(b) hem forming apparatus following the tape unwind apparatus for
receiving the draw tape material as first top and second bottom
draw tapes, and for forming the first top layer and second bottom
layer hems and incorporating the draw tape material into the hems;

(c) hem sealing apparatus for sealing the first top layer and second
bottom layer edge portions to the respective first and second main
body portions of the respective layers, thus sealing the hems and
securing the respective draw tapes therein; and

(d) hole forming apparatus disposed up-stream in said machine from
said hem forming apparatus, said hole forming apparatus
comprising:







- 40 -

(i) in-turn and back-fold plows for receiving the first top and
second bottom edge portions of the web in a flat disposition
and folding the first top layer and second bottom layer edge
portions nested together back onto one of the first and
second main body portions of the web, and

(ii) a cutter for forming holes, at spaced locations in the nested
top and bottom layer edge portions adjacent respective first
top and second bottom free edges of the web before said
hem forming apparatus forms the first and second hems.

41. The machine as in claim 40, said hem forming apparatus forming
the first and second hems about the first and second draw tapes.

42. The machine as in claim 40, said hem forming apparatus including
first and second hem folding plows having first and second hem folding
edges extending at first and second transverse angles to the direction of
travel of the web and folding the first and second edge portions of the web,
and first and second hem forming plows having first and second hem
forming edges extending at third and fourth transverse angles to the
direction of travel of the web and receiving the first and second folded edge
portions from said hem folding edges, and folding the folded edge portions
back onto the respective first and second main body portions, thus forming
the first and second hems.

43. The machine as in claim 42, each said hem folding plow having an
aperture therein, the respective draw tape advancing through the respective







- 41 -

aperture in said hem folding plow for forming of the respective hem about
the tape.

44. The machine as in claim 43, the respective draw tapes advancing
between each said hem folding plow and the respective layers.

45. The machine as in claim 42, said first and second hem folding
edges comprising trailing edges of said hem folding plows, said first and
second hem forming edges comprising leading edges of said hem forming
plows.

46. The machine as in claim 42, and wherein each said draw tape
advances aver the respective said hem folding plow in contact with the
respective layer of web material in parallel with the folding of the edge
portion of the respective layer by the respective said hem folding plow.

47. A machine for providing a draw tape in a plastic web, the plastic
web having top and bottom layers, the top layer having a first main body
portion, and a first top layer edge portion, the bottom layer having a second
main body portion, and second bottom layer edge portion; the first and
second edge portions of the top and bottom layers respectively being folded
onto respective first and second main body portions of the top and bottom
layers, to form respective first top layer and second bottom layer hems, with
respective first top layer and second bottom layer draw tapes being
incorporated into the hems, the first and second edge portions being sealed
to the respective main body portions to form first and second sealed hems,
with the first and second draw tapes in the respective sealed hems, said
machine comprising:





- 42 -

(a) hole forming apparatus, comprising:

(i) plows for receiving the first and second edge portions of the
web in a flat disposition and folding the first and second
edge portions nested together back onto one of the first and
second main body portions of the web,

(ii) a cutter for forming holes, at spaced locations in the nested
top and bottom layer edge portions adjacent respective first
and second free edges of the web; and

(iii) a plow for returning said nested first and second edge
portions to the flat disposition;

(b) tape unwind apparatus downstream from the hole forming
apparatus for feeding first and second draw tapes into proximity
with, and aligned with, the first and second edge portions;

(c) hem forming apparatus adjacent the tape unwind apparatus for
receiving the first and second draw tapes and folding the first and
second edge portions about respective ones of the first and second
draw tapes and onto respective first and second main body
portions of the respective layers, thus forming the first and second
hems about the draw tapes, with the draw tapes inside; and

(d) hem sealing apparatus following the hem forming apparatus for
sealing the first and second edge portions to the respective first
and second main body portions, thus sealing the hems and
securing the respective draw tapes therein.







- 43 -

48. The machine as in claim 47, said hem forming apparatus including
first and second hem folding plows having first and second hem folding
edges extending at first and second transverse angles to the direction of
travel of the web and folding the first and second edge portions of the web,
and first and second hem forming plows having first and second hem
forming edges extending at third and fourth transverse angles to the
direction of travel of the web and receiving the first and second folded edge
portions from said hem folding edges, and folding the folded edge portions
back onto the respective first and second main body portions, thus forming
the first and second hems.

49. The machine as in claim 48, each said hem folding plow having an
aperture therein, the respective draw tape advancing through the respective
aperture in said hem folding plow for forming of the respective hem about
the tape.

50. The machine as in claim 49, the respective draw tapes advancing
between each said hem folding plow and the respective layers.

51. The machine as in claim 48, said first and second hem folding
edges comprising trailing edges of said hem folding plows, said first and
second hem forming edges comprising leading edges of said hem forming
plows.

52. The machine as in claim 48, each said draw tape advances over
the respective said hem folding plow in contact with the respective layer of
web material in parallel with the folding of the edge portion of the
respective
layer by the respective said hem folding plow.







-44-
53. The machine as in claim 47, said top and bottom layers
comprising first and second edge regions respectively, said hem forming
apparatus including a separating plow separating the second edge region of
the bottom layer from the corresponding first edge region of the top layer.
54. The machine as in claim 47, said hem forming apparatus being
disposed downstream in the processing sequence from said hole forming
apparatus.
55. A machine for providing a draw tape in a plastic web, the plastic
web having top and bottom layers, the top layer having a first top layer main
body portion, a first top layer edge portion and a first top layer free edge,
the
bottom layer having a second bottom layer main body portion, a second
bottom layer edge portion, and second bottom layer free edge; the first top
and second bottom edge portions respectively of the top and bottom layers
respectively being folded onto respective first top and second bottom main
body portions of the top and bottom layers, to form respective first top layer
and second bottom layer hems, with respective first top layer and second
bottom layer draw tapes being incorporated into the hems, the first and
second edge portions being sealed to the respective main body portions to
form first top layer and second bottom layer sealed hems, with the first and
second draw tapes in the respective seated hems, the machine comprising:
(a) hole forming apparatus for forming holes at spaced locations in the
web, in the edge portions adjacent respective first top and second
bottom free edges of the web, said hole forming apparatus
including:



-45-
(i) an in-turn plow for receiving the first and second edge
portions of the web in a flat disposition and turning the first
and second edge portions nested inwardly toward the main
body portions of the web,
(ii) a back-fold plow following the in-turn plow for receiving the
in-turned edge portions of the web and folding the nested
edge portions back onto one of the first and second main
body portions of the web, the back-fold plow having a
notch,
(iii) a hole cutter located adjacent the notch in said back-fold
plow for cutting holes in the web as the web traverses the
notch, and
(iv) an out-turning plow following the hole cutter for receiving
the first and second edge portions from the back-fold plow
and restoring the first and second edge portions to a flat
condition;
(b) tape unwind apparatus adjacent the hole forming apparatus for
feeding draw tape material into proximity with the first and second
edges;
(c) hem forming apparatus disposed downstream in the processing
sequence from the hole forming apparatus for receiving the draw
tape material as first and second draw tapes, and forming the first
and second hems; and



-46-
(d) hem sealing apparatus adjacent the hem forming apparatus for
sealing the first and second edge portions to the respective web
layers, thus sealing the hems and securing the respective draw
tapes therein.
56. The machine as in claim 55, said in-turn plow receiving the web
with the top layer in overlying contact with the bottom layer, and folding the
first and second edge portions with the first edge portion of the top layer
nested inside the second edge portion of the bottom layer.
57. The machine as in claim 55, said hem forming apparatus forming
the first and second hems about the first and second draw tapes.
58. The machine as in claim 55, said hem forming apparatus including
first and second hem folding plows having first and second hem folding
edges extending at first and second transverse angles to the direction of
travel of the web and folding the first and second edge portions of the web,
and first and second hem forming plows having first and second hem
forming edges extending at third and fourth transverse angles to the
direction of travel of the web and receiving the first and second folded edge
portions from said hem folding edges, and folding the folded edge portions
back onto the respective first and second main body portions, thus forming
the first and second hems.
59. The machine as in claim 58, each said hem folding plow having an
aperture therein, the respective draw tape advancing through the respective
aperture in said hem folding plow for forming of the respective hem about
the tape.




-47-
60. The machine as in claim 59, the respective draw tapes advancing
between each said hem folding plow and the respective layers.
61. The machine as in claim 58, said first and second hem folding
edges comprising trailing edges of said hem folding plows, said first and
second hem forming edges comprising leading edges of said hem forming
plows.
62. The machine as in claim 61 wherein said hem folding plows and
said hem forming plows each have web contact surfaces for contacting
respective edge regions of the respective top and bottom layers of said web,
said web contact surfaces on said first hem forming plow and said first hem
folding plow being disposed at an obtuse dihedral angle with respect to each
other, and said web contact surfaces on said second hem forming plow and
said second hem folding plow being disposed at an obtuse dihedral angle
with respect to each other.
63. The machine as in claim 58 wherein each said draw tape
advances over the respective said hem folding plow in contact with the
respective layer of web material in parallel with the folding of the edge
portion of the respective layer by the respective said hem folding plow.
64. The machine as in claim 55, said in-turn plow having an outer
edge disposed at an angle with respect to a free edge of the web, extending
inwardly across the web along the direction of travel of the web, and aligned
with a first inner edge of said back-fold plow, said first inner edge of said
back-fold plow being disposed at an angle with respect to an edge of the
web approximately equal to the angle formed by the outer edge of the in-
turn plow with respect to an edge of the web, said back-fold plow having a


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second inner edge, intersecting said first inner edge and being disposed at an
angle with respect to a free edge of the web, approximately equal to the
angle formed by the outer edge of the in-turn plow with respect to a free
edge of the web, but advancing outwardly across the web along the
direction of advance of the web, said out-turning plow having an outer edge
aligned with said second inner edge of said back-fold plow, respective loci on
said outer edges on said in-turn plow and said out-turning plow being aligned
with each other along a transverse dimension of the web.
65. The machine as in claim 64, said back-fold plow having an outer
edge extending in the direction of travel of said web, having a notch in said
outer edge, and a hole cutter adjacent the notch in said outer edge of the
back-fold plow for cutting spaced holes in the folded edge portions of the
top and bottom layers of the web as the folded edge portions traverse the
notch.
66. The machine as in claim 55, said in-turn plow, said back-fold
plow, and said out-turning plow having respective first, second, and third
web guiding surfaces guiding the web adjacent said edge portions, said first
and third web guiding surfaces being disposed at obtuse angles with respect
to said second web guiding surface.
67. The machine as in claim 66, said first and third web guiding
surfaces defining substantially equal and opposite angles from said second
web guiding surface.
68. The machine as in claim 55, said top and bottom layers
comprising first and second edge regions respectively, said hem forming


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apparatus including a separating plow separating the second edge region of
the bottom layer from the corresponding first edge region of the top layer.
69. The machine as in claim 55, including at least one turning member
downstream of said hem forming apparatus, assisting in returning the edge
regions into face-to-face relationship with each other.
70. The machine as in claim 69, said at least one turning member
comprising an upstanding turning cone.
71. The machine as in claim 70, including a second turning member
downstream of said turning cone, returning the separated one of the edge
regions into face-to-face relationship with the other of the edge regions
being
effected by said turning cone.
72. A method of providing a draw tape in a plastic web, the plastic
web being folded longitudinally along the length thereof to form top and
bottom layers of the plastic web, first and second edge portions of the top
and bottom layers respectively being folded onto respective first and second
main body portions of the top and bottom layers, to form respective first and
second hems, with respective first and second draw tapes in the hems, the
first and second edge portions being sealed to the respective main body
portions to form first and second sealed hems with the first and second draw
tapes therein, the method comprising the steps of:
(a) forming holes at spaced locations in the edge portions adjacent
first and second free edges of the web by (i) receiving the first and
second edge portions of the web in a flat disposition and turning
the first and second edge portions inwardly toward the main body



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portions of the web, with one of the first and second edge portions
nested in the other of the first and second edge portions, (ii)
folding the edge portions back onto the main body portion of the
nested one of the first and second edge portions, and (iii) forming
holes in the first and second edge portions at loci adjacent but
spaced from free edges of the respective layers;
(b) feeding draw tape material into proximity with the first and second
edge portions;
(c) receiving the draw tape material as first and second draw tapes
and forming the first and second hems and incorporating the first
and second draw tapes into the hems; and
(d) seating the first and second edge portions to the respective first
and second main body portions of the respective layers to form the
first and second sealed hems, and thus sealing the hems and
securing the respective draw tapes therein.
73. A method as in claim 72, including unfolding the edge portions
with the holes therein and restoring the first and second edge portions to a
flat condition.
74. A method as in claim 73, including re-folding the first and second
edge portions at respective first and second hem folding plows and
advancing the respective draw tapes over the respective hem folding plows
in contact with the respective layers of web material in parallel with the
folding of the respective edge portions by the respective hem folding plows.


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75. A method as in claim 74, each hem folding plow having an
aperture therein, the method including advancing the draw tapes through the
apertures in the respective hem folding plows.

76. A method as in claim 74, each hem folding plow having an
aperture therein, the method including advancing the draw tapes through the
apertures in the respective hem folding plows and into contact with the
respective top and bottom layers, with the draw tapes disposed between the
hem folding plows and the respective layers of the web.

77. A method as in claim 76, including advancing the respective layer
and draw tape together across a leading edge of a hem forming plow and
thus folding a free edge of the respective layer under the respective draw
tape to form the respective hem, with the draw tape contained therein.

78. A method as in claim 73, forming of the first and second hems
including folding the unfolded first and second edge portions onto respective
first and second ones of the main body portions of the respective layers.

79. A method as in claim 73, including re-folding the first and second
edge portions onto the first and second ones of the main body portions of
the respective layers, and forming the first and second hems, wit h the first
and second draw tapes therein, and sealing the first and second free edges
of the respective edge portions to the main bodies of the top and bottom
layers respectively, with the draw tapes therein.

80. A method as in claim 79, the re-folding comprising folding
respective edge portions about the respective first and second draw tapes.




-52-

81. A method as in claim 81, including, prior to re-folding the first and
second edge portions, separating first and second edge regions, including the
respective first and second edge portions, of the top and bottom layers from
each other, white holding the remainders of the top and bottom layers in
surface-to-surface contact with each other.

82. A method as in claim 81, including returning the separated one of
the edge regions into face-to-face relationship with the other of the edge
regions after seating the first and second hems.

83. A method as in claim 81, including returning the separated one of
the edge regions into face-to-face relationship with the other of the edge
regions, over an upstanding turning cone, after sealing the first and second
hems.

84. A method as in claim 79, the re-folding comprising folding each
respective edge portion about a trailing edge of a hem folding plow and
receiving the folded edge portion and forming the hem therefrom by passing
the folded edge over a leading edge of a hem forming plow.

85. A method as in claim 72, including forming the first and second
hems downstream of forming the holes in the edge portions.

86. A method as in claim 72, including re-folding the first and second
edge portions about first and second hem folding plows and separating first
and second edge regions of the top and bottom layers, including the
respective edge portions, at a separating plow for traverse along parallel but
spaced first and second paths, the first hem folding plow and the separating
plow, in combination, comprising a separating notch formed by cooperating




-53-

elements thereof, the method including traversing the second edge portion of
the bottom layer transversely across the separating notch and thereby
initiating separation of the second edge regions from the first edge region.

87. A method as in claim 86, including traversing the second edge
portion across the separating notch while the bottom layer is under tension.

88. A method as in claim 86, including traversing the second edge
portion transversely across the separating notch while the first edge portion
extends across the notch and thereby initiating separation of the first and
second edge regions.

89. A method as in claim 84, including returning the separated one of
the edge regions into face-to-face relationship with the other of the edge
regions, over an upstanding turning cone, after sealing the first and second
hems.

90. A method as in claim 72, including controlling the temperature of
the web at the formed hems before sealing the edge portions to the
respective main body portions in forming the hem seals.

91. A method of providing a draw tape in a plastic web, the plastic
web being folded longitudinally along the length thereof to form top and
bottom layers of the plastic web, first and second edge portions of the top
and bottom layers respectively being folded onto respective first and second
main body portions of the top and bottom layers, to form respective first and
second hems, with respective first and second draw tapes in the hems, the
first and second edge portions being sealed to the respective main body




-54-

portions to form first and second sealed hems with the first and second draw
tapes therein, the method comprising the steps of:
(a) feeding draw tape material into proximity with the first and second
edge portions;
(b) receiving the draw tape material as first and second draw tapes
and forming the first and second hems and incorporating the first
and second draw tapes into the hems;
(c) sealing the first and second edge portions to the respective first
and second main body portions of the respective layers, thus
sealing the hems and securing the respective draw tapes therein;
and
(d) prior to forming the hems and receiving the draw tapes, the step of
forming holes at spaced locations in the edge portions adjacent
first and second free edges of the web.

92. A method as in claim 91, the step of forming holes including
receiving the first and second edge portions of the web in a flat disposition
and turning the first and second edge portions toward the main body
portions of the web, (ii) folding the edge portions back onto at least one of
the main body portions, (iii) forming holes in the first and second edge
portions at loci adjacent but spaced from the free edges thereof, and (iv)
unfolding the edge portions with the holes therein and restoring the first and
second edge portions to flat disposition.




-55-

93. A method as in claim 91, the method including forming the first
and second hems about the first and second draw tapes.

94. A method as in claim 91, the step of forming the holes including
folding the first and second edge portions back onto at least one main body
portion and, after forming the holes, unfolding the first and second edge
portions prior to forming the hems.

95. A method as in claim 94, including re-folding the first and second
edge portions onto the first and second ones of the main body portions of
the respective layers, and forming the first and second hems, with first and
second draw tapes therein, and sealing the first and second free edges of the
respective edge portions to the main bodies of the top and bottom layers
respectively, with the draw tapes therein.

96. A method as in claim 95, including, prior to re-folding the first and
second edge portions, separating first and second edge regions, including the
respective first and second edge portions, of the top and bottom layers from
each other, while holding the remainders of the widths of the top and
bottom layers in surface-to-surface contact with each other.

97. A method as in claim 96, including returning the separated one of
the edge regions into face-to-face relationship with the other of the edge
regions, after sealing the first and second hems.

98. A method as in claim 95, the re-folding comprising folding each
respective edge portion about a trailing edge of a hem folding plow and
receiving the folded edge portion and forming the hem therefrom by passing
the folded edge over a leading edge of a hem forming plow.




-56-

99. A method as in claim 94, the re-folding comprising folding
respective edge portions about the respective first and second draw tapes.

100. A method as in claim 94, including refolding the first and second
edge portions at respective first and second hem folding plows and
advancing the respective draw tapes over the respective said hem folding
plows in contact with the respective layers of web material in parallel with
the folding of the respective edge portions by the respective hem folding
plows.

101. A method as in claim 100, each hem folding plow having an
aperture therein, the method including advancing the draw tapes through the
apertures in the respective hem folding plows.

102. A method as in claim 100, each hem folding plow having an
aperture therein, the method including advancing the draw tapes through the
apertures in the respective hem folding plows and into contact with the
respective top and bottom layers, with the draw tapes disposed between the
hem folding plows and the respective layers of the web.

103. A method as in claim 102, including advancing the respective
layer and draw tape together across a leading edge of a hem forming plow
and thus folding a free edge of the respective layer under the respective
draw tape to form the respective hem, with the draw tape contained therein.

104. A method as in claim 94, including re-folding the first and second
edge portions about first and second hem folding plows and separating first
and second edge regions of the top and bottom layers, including the




-57-

respective edge portions, at a separating plow for traverse along parallel but
spaced first and second paths, the first hem folding plow and the separating
plow, in combination, comprising a separating notch formed by cooperating
elements thereof, the method including traversing the second edge portion of
the bottom layer transversely across the separating notch and thereby
initiating separation of the second edge region from the first edge region.

105. A method as in claim 104, including traversing the second edge
portion transversely across the separating notch while the first edge portion
extends across the notch and thereby initiating separation of the first and
second edge regions.

106. A method as in claim 104, including returning the separated one
of the edge regions into face-to-face relationship with the other of the edge
regions, over an upstanding turning cone, after sealing the first and second
hems.

107. A method as in claim 91, forming of the first and second hems
including folding the unfolded first and second edge portions onto respective
first and second ones of the main body portions of the respective layers.

108. A method as in claim 91, including controlling the temperature of
the web at the formed hems before sealing the edge portions to the
respective main body portions in forming the hem seals.

109. A method of providing a draw tape in a plastic web, the plastic
web being folded longitudinally along the length thereof to form top and
bottom layers of the plastic web, first and second edge portions of the top
and bottom layers respectively being folded onto respective first and second




-58-

main body portions of the top and bottom layers, to form respective first and
second hems, with respective first and second draw tapes in the hems, the
first and second edge portions being sealed to the respective main body
portions to form first and second sealed hems with the first and second draw
tapes therein, the method comprising the steps of:

(a) forming holes, at spaced locations in the web, in the edge portions
adjacent respective first and second free edges of the web;

(b) feeding first and second draw tapes into proximity with, and
aligned with, the first and second edge portions;

(c) receiving the draw tapes and folding the first and second edge
portions about respective ones of the first and second draw tapes
and onto respective first and second ones of the main body
portions of the respective layers thus forming the first and second
hems about the draw tapes, with the draw tapes inside; and

(d) sealing the first and second edge portions to the respective first
and second main body portions of the respective layers to form the
first and second sealed hems, and thus sealing the hems and
securing the respective draw tapes therein.

110. A method as in claim 109, forming of the first and second hems
including folding the unfolded first and second edge portions onto respective
first and second ones of the main body portions of the respective layers.

111. A method as in claim 109, including, prior to folding the first and
second edge portions, separating first and second edge regions, including the


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respective first and second edge portions, of the top and bottom layers from
each other, while holding the remainders of the widths of the top and
bottom layers in surface-to-surface contact with each other.

112. A method as in claim 111, including returning the separated one
of the edge regions into face-to-face relationship with the other of the edge
regions after sealing the first and second hems.

113. A method as in claim 109, including forming the first and second
hems downstream of forming the holes in the edge portions.

114. A method as in claim 109, the folding comprising folding each
respective edge portion about a trailing edge of a hem folding plow and
receiving the folded edge portion and forming the hem therefrom by passing
the folded edge over a leading edge of a hem forming plow.

115. A method as in claim 109, including folding the first and second
edge portions at respective first and second hem folding plows and
advancing the respective draw tapes over the respective said hem folding
plows in contact with the respective layers of web material in parallel with
the folding of the respective edge portions by the respective hem folding
plows.

116. A method as in claim 109, each hem folding plow having an
aperture therein, the method including advancing the draw tapes through the
apertures in the respective hem folding plows.

117. A method as in claim 109, each hem folding plow having an
aperture therein, the method including advancing the draw tapes through the




-60-

apertures in the respective hem folding plows and into contact with the
respective top and bottom layers, with the draw tapes disposed between the
hem folding plows and the respective layers of the web material.

118. A method as in claim 109, including advancing the respective
layer and draw tape together across a leading edge of a hem forming plow
and thus folding a free edge of the respective layer under the respective
draw tape to form the respective hem, with the draw tape contained therein.

119. A method as in claim 109, including re-folding the first and
second edge portions about first and second hem folding plows and
separating first and second edge regions of the top and bottom layers,
including the respective edge portions, at a separating plow for traverse
along parallel but spaced first and second paths, the first hem folding plow
and the separating plow, in combination, comprising a separating notch
formed by cooperating elements thereof, the method including traversing the
second edge portion of the bottom layer transversely across the separating
notch and thereby initiating separation of the second edge region from the
first edge region.

120. A method as in claim 119, including returning the separated one
of the edge regions into face-to-face relationship with the other of the edge
regions, over an upstanding turning cone, after sealing the first and second
hems.

121. A method as in claim 109, including traversing the second edge
portion across the separating notch while the bottom layer is under tension.




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122. A method as in claim 109, including traversing the second edge
portion transversely across the separating notch white the first edge portion
extends across the notch and thereby initiating separation of the first and
second edge regions.

123. A method of providing a draw tape in a plastic web, the plastic
web being folded longitudinally along the length thereof to form top and
bottom layers of the plastic web, first and second edge portions of the top
and bottom layers respectively being folded onto respective first and second
main body portions of the top and bottom layers, to form respective first and
second hems, with respective first and second draw tapes in the hems, the
first and second edge portions being sealed to the respective main body
portions to form first and second sealed hems with the first and second draw
tapes therein, the method comprising the steps of:

(a) forming holes, at spaced locations in the edge portions adjacent
respective first and second free edges of the web, including folding
the edge portions back onto the main body portion of at least one
of the layers, forming the holes while the edge portions are folded,
and subsequently unfolding the edge portions;

(b) feeding first and second draw tapes into proximity with, and
aligned with, the first and second edge portions;

(c) receiving the draw tapes and the unfolded edge portions of the
web with holes therein, at a hem forming station, re-folding the
first and second edge portions, toward each other and onto first
and second ones of the main body portions of the respective
layers, and incorporating the draw tapes into the hems, thus



-62-
forming the first and second hems and incorporating the draw
tapes inside; and
(d) sealing the first and second edge portions to the respective first
and second main body portions, thus sealing the hems and
securing the respective draw tapes therein.
124. A method as in claim 123, the re-folding comprising folding
respective edge portions about the respective first and second draw tapes.
125. A method as in claim 123, including, prior to re-folding the first
and second edge portions, separating first and second edge regions,
including the respective first and second edge portions, of the to p and
bottom layers from each other, while holding the remainders of the widths of
the top and bottom layers in surface-to-surface contact with each other.
126. A method as in claim 125, including returning the separated one
of the edge regions into face-to-face relationship with the other of the edge
regions after sealing the first and second hems.
127. A method as in claim 123, the re-folding comprising folding each
respective edge portion about a trailing edge of a hem folding plow and
receiving the folded edge portion and forming the hem therefrom by passing
the folded edge over a leading edge of a hem forming plow.
128. A method as in claim 123, including re-folding the first and
second edge portions at respective first and second hem folding plows and
advancing the respective draw tapes over the respective said hem folding
plows in contact with the respective layers of web material in parallel with



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the folding of the respective edge portions by the respective hem folding
plows.
129. A method as in claim 128, each hem folding plow having an
aperture therein, the method including advancing the draw tapes through the
apertures in the respective hem folding plows.
130. A method as in claim 128, each hem folding plow having an
aperture therein, the method including advancing the draw tapes through the
apertures in the respective hem folding plows and into contact with the
respective top and bottom layers, with the draw tapes disposed between the
hem folding plows and the respective layers of the web.
131. A method as in claim 130, including advancing the respective
layer and draw tape together across a leading edge of a hem forming plow
and thus folding a free edge of the respective layer under the respective
draw tape to form the respective hem, with the draw tape contained therein.
132. A method as in claim 123, including re-folding the first and
second edge portions about first and second hem folding plows and
separating first and second edge regions of the top and bottom layers,
including the respective edge portions, at a separating plow for traverse
along parallel but spaced first and second paths, the first hem folding plow
and the separating plow, in combination, comprising a separating notch
formed by cooperating elements thereof, the method including traversing the
second edge portion of the bottom layer transversely across the separating
notch and thereby initiating separation of the second edge region from the
first edge region.


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133. A method as in claim 132, including traversing the second edge
portion transversely across the separating notch while the first edge portion
extends across the notch and thereby initiating separation of the first and
second edge regions.
134. A method as in claim 123, including controlling the temperature
of the web at the formed hems before sealing the edge portions to the
respective main body portions in forming the hem seals.
135. A method of providing a draw tape in a plastic web, the plastic
web being folded longitudinally along the length thereof to form top and
bottom layers of the plastic web, first and second edge portions of the top
and bottom layers respectively being folded onto respective first and second
main body portions of the top and bottom layers, to form respective first and
second hems, with respective first and second draw tapes in the hems, the
first and second edge portions being sealed to the respective main body
portions to form first and second sealed hems with the first and second draw
tapes therein, the method comprising the steps of;
(a) forming holes, at spaced locations in the edge portions adjacent
respective first and second free edges of the web;
(b) feeding draw tape material into proximity with the first and second
edge portions;
(c) receiving the draw tape material as first and second draw tapes
and forming the first and second hems and incorporating the draw
tape material into the hems; and



-65-
(d) sealing the first and second edge portions to the respective first
and second main body portions of the respective layers by applying
seal-forming heat from heat seal apparatus to the web, thus sealing
the hems and securing the respective draw tapes therein, and
cooling the temperature of the web at the formed hems to a
predictable controlled temperature before applying the seal-forming
heat to the web, thus to present the formed hems, at the
controlled temperature, to the heat seal apparatus.
136. A method as in claim 135, including controlling the temperature
of the web downstream of, and adjacent, the sealing of the first and second
edge portions to the main body portions of the respective layers.
137. A method of providing a draw tape in a plastic web, the plastic
web being folded longitudinally along the length thereof to form top and
bottom layers of the plastic web, first and second edge portions of the top
and bottom layers respectively being folded onto respective first and second
main body portions of the top and bottom layers, to form respective first and
second hems, with respective first and second draw tapes in the hems, the
first and second edge portions being sealed to the respective main body
portions to form first and second sealed hems with the first and second draw
tapes therein, the method comprising the steps of:
(a) forming holes, at spaced locations in the web, in the edge portions
adjacent respective first and second free edges of the web;
(b) feeding first and second draw tapes into proximity with, and
aligned with, the first and second edge portions;


-66-
(c) separating first and second edge regions of the top and bottom
layers from each other for traverse along parallel but spaced first
and second paths while holding the remainders of the widths of the
top and bottom layers in surface-to-surface contact with each
other, the first and second edge regions including the respective
first and second edge portions and the respective first and second
free edges, the hem forming apparatus receiving the first and
second draw tapes;
(d) folding the first and second edge portions onto respective first and
second ones of the main body portions in the edge regions of the
respective layers and, thus forming the first and second hems and
incorporating the draw tapes into the hems; and
(e) sealing the first and second edge portions to the respective first
and second main body portions of the respective layers, thus
sealing the hems and securing the respective draw tapes therein.
138. A method as in claim 137, including forming the holes upstream
in the method from the separating of the edge regions.
139. A method as in claim 137, the folding comprising folding each
respective edge portion about a trailing edge of a hem folding plow and
receiving the folded edge portion and forming the hem therefrom by passing
the folded edge over a leading edge of a hem forming plow.
140. A method as in claim 137, including folding the first and second
edge portions at respective first and second hem folding plows and
advancing the respective draw tapes over the respective said hem folding



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plows in contact with the respective layers of web material in parallel with
the folding of the respective edge portions by the respective hem folding
plows.
141. A method as in claim 140, each hem folding plow having an
aperture therein, the method including advancing the draw tapes through the
apertures in the respective hem folding plows.
142. A method as in claim 140, each hem folding plow having an
aperture therein, the method including advancing the draw tapes through the
apertures in the respective hem folding prows and into contact with the
respective top and bottom layers, with the draw tapes disposed between the
hem folding plows and the respective layers of the web.
143. A method as in claim 142, including advancing the respective
layer and draw tape together across a leading edge of a hem forming plow
and thus folding a free edge of the respective layer under the respective
draw tape to form the respective hem, with the draw tape contained therein.
144. A method as in claim 137, including re-folding the first and
second edge portions about first and second hem folding plows and
separating first and second edge regions of the top and bottom layers,
including the respective edge portions, at a separating plow for traverse
along parallel but spaced first and second paths, the first hem folding plow
and the separating plow, in combination, comprising a separating notch
formed by cooperating elements thereof the method including traversing the
second edge portion of the bottom layer transversely across the separating
notch and thereby initiating separation of the second edge region from the
first edge region.


-68-
145. A method as in claim 144, including traversing the second edge
portion across the separating notch while the bottom layer is under tension.
146. A method as in claim 144, including traversing the second edge
portion transversely across the separating notch while the second edge
portion extend across the notch and thereby initiating separation of the first
and second edge regions.
147. A method as in claim 137, including returning the separated one
of the edge regions into face-to-face relationship with the other of the edge
regions after sealing the first and second hems.
148. A method as in claim 137, including returning the separated one
of the edge regions into face-to-face relationship with the other of the edge
regions, over an upstanding turning cone, after sealing the first and second
hems.
149. A method as in claim 137, including turning portions of the top
and bottom layers about a turning member downstream of the hem forming
apparatus, including air lubrication between the turning member and the
respective portion of the bottom layer.
150. Method as in claim 137, the separating of the first and second
edge regions comprising separating one of first and second edge regions
from the other of the first and second edge regions at an angle of about 30
degrees to about 160 degrees.



-69-
151. A method of providing a draw tape in a plastic web, the plastic
web being folded longitudinally along the length thereof to form top and
bottom layers of the plastic web, first and second edge portions of the top
and bottom layers respectively being folded onto respective first and second
main body portions of the top and bottom layers, to form respective first and
second hems, with respective first and second draw tapes in the hems, the
first and second edge portions being sealed to the respective main body
portions to form first and second sealed hems with the first and second draw
tapes therein, the method comprising the steps of:
(a) forming holes, at spaced locations in the web, in the edge portions
adjacent respective first and second free edges of the web;
(b) feeding draw tape material into proximity with the first and second
edge portions; and
(c) forming and sealing hems in the web by receiving the draw tape
material as first and second draw tapes, folding the first and
second edge portions onto respective first and second ones of the
main body portions of the respective layers, thus forming the first
and second hems with the draw tapes in the hems, and sealing the
first and second edge portions to the respective first and second
main body portions of the respective layers using respective first
and second hem sealing elements, thus sealing the hems and
securing the respective draw tapes therein, and
applying transverse stretching forces to the web at the first and second
hems, with the draw tapes therein, upstream of the respective first and
second sealing elements.



-70-
152. A method as in claim 151, the folding comprising folding
respective edge portions about the respective first and second draw tapes.
153. A method as in claim 151, including, prior to folding the first and
second edge portions, separating first and second edge regions, including the
respective first and second edge portions, of the top and bottom layers from
each other, while holding the remainders of the widths of the top and
bottom layers in surface-to-surface contact with each other.
154. A method as in claim 151, including forming the first and second
hems downstream of forming the holes in the edge portions.
155. A method as in claim 151, including electrostatic pinning the first
and second formed hems to respective first and second underlying supports,
and thereby controlling transverse positioning of the respective layers to the
equipment downstream of the electrostatic pinning step and upstream and
adjacent the hem sealing step.
156. A method as in claim 151, the first and second underlying
supports extending under the respective hem sealing element, and
supporting the hems while the hems are being sealed.
157. A method as in claim 151, including applying force on the web
directed against an underlying support having a surface generally parallel to
the surface of the web.
158. A method of providing a draw tape in a plastic web, the plastic
web being folded longitudinally along the length thereof to form top and
bottom layers of the plastic web, first and second edge portions of the top


-71-
and bottom layers respectively being folded onto respective first and second
main body portions of the top and bottom layers, to form respective first and
second hems, with respective first and second draw tapes in the hems, the
first and second edge portions being sealed to the respective main body
portions to form first and second sealed hems with the first and second draw
tapes therein, the method comprising the steps of:
(a) forming holes, at spaced locations in the web, in the edge portions
adjacent respective first and second free edges of the web;
(b) feeding first and second draw tapes into proximity with the first
and second edge portions; and
(c) forming and sealing hems in the web by receiving the draw tapes,
folding the first and second edge portions onto respective first and
second ones of the main body portions of the respective layers,
thus forming the first and second hems, and incorporating the draw
tapes in the hems, and sealing the first and second edge portions
to the respective first and second main body portions of the
respective layers using respective first and second hem sealing
elements, thus sealing the first and second hems and securing the
respective draw tapes therein,
including electrostatic pinning of the formed hems, with draw tapes therein,
to underlying supports, and thereby controlling transverse positioning of the
hems with respect to said equipment while the hem seals are being formed.
159. A method as in claim 158, the folding comprising folding
respective edge portions about the respective first and second draw tapes.




-72-

160. A method as in claim 158, including, prior to folding the first and
second edge portions, separating first and second edge regions, including the
respective first and second edge portions, of the top and bottom layers from
each other, while holding the remainders of the widths of the top and
bottom layers in surface-to-surface contact with each other.

161 . A method as in claim 158, including folding the first and second
edge portions at respective first and second hem folding plows and
advancing the respective draw tapes over the respective said hem folding
plows in contact with the respective layers of web material in parallel with
the folding of the respective edge portions by the respective hem folding
plows.

162. A method as in claim 158, including applying transverse
stretching forces to the layers with stretching devices at the first and
second
hems, with the draw tapes therein, prior to forming the hem seals, the
underlying supports extending from the respective stretching devices to the
respective hem sealing elements, thereby supporting the hems from the time
the layers are stretched until the hems are sealed.

163. A method as in claim 162, including supporting the hems with
supports at the seal loci while the hems are being sealed.

164. A method as in claim 158, the underlying support comprising a
support bar, and a driven belt between the support bar and the respective
hem, supporting the respective hem, and moving with the hem thereon, from
the electrostatic pinning device to the respective hem sealing element.


-73-

165. A method of providing a draw tape in a plastic web, the plastic
web being folded longitudinally along the length thereof to form top and
bottom layers of the plastic web, first and second edge portions of the top
and bottom layers respectively being folded onto respective first and second
main body portions of the top and bottom layers, to form respective first and
second hems, with respective first and second draw tapes in the hems, the
first and second edge portions being sealed to the respective main body
portions to form first and second sealed hems with the first and second draw
tapes therein, the method comprising the steps of:
(a) forming holes, at spaced locations in the web, in the edge portions
adjacent respective first and second free edges of the web;
(b) separating one of first and second edge regions of the top and
bottom layers from the other of the first and second edge regions
at an angle of at least 30 degrees while holding the remainders of
the widths of the top and bottom layers in surface-to-surface
contact with each other and maintaining the other of the first and
second edge regions as a generally straight line extension of the
remainder of the width of the respective layer;
(c) feeding draw tape material into proximity with the first and second
edge portions;
(d) forming and sealing hems in the web at the separated first and
second edge regions, by receiving the draw tape material at the
respective edge portions, folding the first and second edge portions
onto respective first and second ones of the main body portions of
the respective layers, thus forming the first and second hems, and


-74-

incorporating the draw tape material in the hems, and sealing the
first and second edge portions to the respective first and second
main body portions of the respective layers, thus sealing the hems
and securing the respective draw tapes in the respective sealed
hems while the first and second edge regions are so separated; and
(e) returning the separated one of the edge regions into face-to-face
relationship with the other of the edge regions over an upstanding
turning cone disposed downstream of the hem sealing step.

166. A method as in claim 165, including separating the first and
second edge regions at an angle of from 30 degrees to about 160 degrees.

167. A method as in claim 165, the method including returning the
separated one of the edge regions into face-to-face relationship with the
other of the edge regions over an upstanding turning cone and under a
second turning member, downstream of the turning cone.

168. A method as in claim 165, the method including maintaining the
other of the first and second edge regions as a generally straight line
extension of the remainder of the width of the respective layer.

169. A method of providing a draw tape in a plastic web, the plastic
web being folded longitudinally along the length thereof to form top and
bottom layers of the plastic web, first and second edge portions of the top
and bottom layers respectively being folded onto respective first and second
main body portions of the top and bottom layers, to form respective first and
second hems, with respective first and second draw tapes in the hems, the
first and second edge portions being sealed to the respective main body


-75-

portions to form first and second sealed hems with the first and second draw
tapes therein, the method comprising the steps of:
(a) forming holes, at spaced locations in the edge portions adjacent
respective first and second free edges of the web;
(b) feeding draw tape material into proximity with the first and second
edge portions;
(c) receiving the draw tape material as first and second draw tapes
and forming the first and second hems and incorporating the draw
tape material into the hems; and
(d) sealing the first and second edge portions to the respective first
and second main body portions of the respective layers by applying
seal-forming heat from heat seal apparatus to the web, thus sealing
the hems and securing the respective draw tapes therein, and
projecting liquid onto the web such that the web has a predictable
controlled temperature before applying the seal-forming heat to the
web, thus to present the formed hems, at the controlled
temperature, to the heat seal apparatus.

170. A method as in claim 169 wherein the projecting liquid
comprises water.

171. A method as in claim 169 wherein the projected liquid cools the
web.


Description

Note: Descriptions are shown in the official language in which they were submitted.





2~ 92642
-2- 29057 EPO
FIELD OF THE INVENTION
This invention relates to plastic bags characterized by a
draw tape which, when pulled, causes the bag mouth to constrict
to a substantially closed condition.
Plastic bags of the type described here are typically
comprised of a bag body folded to form top and bottom layers
which are typically cut and sealed at the side edges. The front
edges of the top and bottom layers, located opposite the fold,
define the mouth of the bag. A near margin at the bag mouth is
typically folded inside the bag to form a hem which is
ordinarily sealed to the bag body to form a channel holding draw
tapes. Pulling on accessible portions of the draw tapes causes
the bag mouth to constrict thus closing the bag at its top.
Draw "string" bags have long been utilized, and have taken
many forms. While drawstring bags made of plastic have been
utilized to some extent, such bags have been used mostly in the
lower volume boutique bag market because bags using draw
"strings" tend to be more expensive. Much of the reason for
this limitation in the market area is the cost of producing a
draw "string" bag.
Manufacturing a plastic draw "string" bag typically
requires special processing steps related to joining ends of the
string being used. The string must be knotted, provided with
a metal fastener, or otherwise fixed together at two ends in
each such bag. Such processes cannot be carried out by the
equipment usually associated with fabrication steps used to forth ,
seals and cuts in the plastic webbing from which the bag is
derived. Accordingly, additional equipment must be used to so
manipulate the draw "string," at related additional costs.
Subsequently, draw "tape" bags have been developed, first
mostly in the boutique bag area, but now more generally for the
higher volume markets. Draw tape bags represent a major advance
in that a thermoplastic bag (e.g. low density polyethylene or
linear low density polyethylene copolymer or the like) is




2192642
-3- 29057 EPO
provided with a thermoplastic tape (e. g. high density
polyethylene), the tape being heat sealed into the bag during
the process of manufacturing the bag. While draw "tape" bags
in general represent a substantial improvement over draw
"string" bags, there are still numerous difficulties in the
production of the draw tape bags.
In making a draw tape bag in the conventional art, plastic
film material is generally obtained in parent rolls. The roll
is unwound and fed to a draw tape machine. The draw tape
machine forms hems at edges of the web which ultimately form the
top edges of the finished bag, and incorporates draw tape
material into the hems, in addition to cutting holes at the
edges which form the top edges of the finished bag. The hem is
sealed, securing the tapes in the formed hems.
In the alternative, the plastic film material may be
received in-line, from an ongoing film extrusion process.
In effecting the tape insertion, one or two strips of tape
material are unwound from respective parent rolls and fed to the
formed hems of the respective top and bottom layers.
Accordingly, a draw tape machine must handle at least the main
web which is used to form the plastic bag, as well as the one
or two tape webs being inserted into the hems. Normally two
sets of sealing bars or the like are required for forming the
heat seals at the respective two hems after the tapes are
inserted.
Finally, after the draw tape insertion process is
completed, the web is transferred from the draw tape machine to
a bag-forming machine where transverse side seals, and
corresponding cuts, are made across the width of the plastic
web, forming side seals and cutting the continuous web into
individual bags, using conventional heat sealing and cutting
equipment and methods. The steps that form the side seals and
cut the sides of succeeding bags from each other also seal the
draw tapes, in the hems, to the bag material, itself, along the
side edges of the bags, as well as cutting the tapes to a length
corresponding to the full widths of the bags being fabricated.
This invention focuses on the draw tape equipment. Web
material processed in this invention is subsequently transferred




2192642
-4- 29057 EPO
to bag making equipment for further processing as into the
finished individual bags. The equipment of the invention could
readily be incorporated into the bag making machine such that
the draw tape apparatus and bag making apparatus might be
incorporated into one common frame and driven by a single common
controller, integrating the several steps of the overall process
of both the draw tape operation and the bag making and cutting
operation. While such is certainly feasible with the invention
as disclosed herein, the description herein focuses on the novel
aspects of such apparatus which is in general defined in the
draw tape equipment.
Early bag-making equipment was designed on the basis of
intermittent motion. Namely the bag-making equipment would stop
the plastic web for performing bag-making steps, whether for
making side seals in the bags, cutting the bags apart from the
web, or for performing one or more of the earlier steps such as
those associated with forming hems at the top edge of the bags,
or inserting tapes into such hems. After the desired steps)
were performed, transport of the bag was again started and the
bag advanced to subsequent steps. More recently, continuous
motion processing equipment has been developed wherein bag-
making steps are performed while the bag advances continuously
along a processing line.
However, even the most modern bag-making equipment still
includes a variety of problems. Of particular concern in this
invention is the apparatus used to form hems and incorporate
draw tapes into the hems. There is also the issue of
controlling the temperature of the parent web both before and
after the hem sealing step. There is also the issue of
minimizing the amount of floor space occupied by the bag forming
machinery while retaining the web being processed where workers
can reach it from floor level. Finally, there is the issue of
improving handling of the parent web during its traverse
through the bag forming operation.
It is an object of the invention to provide draw tape
equipment and methods for forming hems around the draw tapes,
rather than inserting the draw tapes into already-formed hems.




2192642
. .
-5- 29057 EPO
It is another object to provide draw tape draw tape
equipment and methods wherein holes are formed adjacent the free
edges of the plastic web before the free edges are folded for
incorporation of draw tapes therein.
It is still another object to provide draw tape draw tape
equipment and methods controlling the temperature of the parent
web material both before and after applying sealing heat to
formed hems.
It is yet another object to provide draw tape draw tape
equipment and methods, separating edge regions of the top and
bottom layers of the plastic and forming hem seals on both the
top and bottom layers along parallel paths.
It is a further obj ect of the invention to minimize the
floor space occupied by the draw tape equipment while
maintaining the web being processed at a level which can be
reached by workmen standing on the floor of the work place.
Another object is to stretch the web adjacent the formed
hems, with the draw tapes therein, prior to forming the seals
at the formed hems.
A still further object is to electrostatically pin the
formed hems to an underlying support, and to carry the thus
pinned hems along the processing line on an intervening belt,
thus controlling the transverse positioning of the hem with
respect to hem sealing apparatus, for forming the hem seals.
A further object is to provide an angled turning member for
assisting in returning the edge regions of the top and bottom
layers into surface-to-surface contact with each other after the
hem seals are formed along parallel paths.




2 i 92b4?~
-6- 9057 EPO
~MMARY OF THE INVENTION
This invention pertains generally to apparatus and methods
for incorporating draw tapes into plastic and like bags. In
general, a continuous length of a plastic tube is unwound from
a parent roll, and slit at a slitting station to form upper and
lower layers, and respective free edges. The web then passes
to a hole forming station where holes are formed in the top and
bottom layers adjacent the free edges. Prior to forming holes,
edge portions of the respective top and bottom layers are folded
against the main body portion of one of the layers, with one of
the edge portions nested in the other of the edge regions.
After holes are formed, the edge regions of the top and
bottom layers are separated from each other by a separating plow
while the remainders of the layers are maintained in surface-to
surface contact with each other. The edge regions traverse
parallel paths while hems are formed in the respective edge
regions, while tapes are incorporated into the hems, and while
the respective hems are sealed to the main body members of the
respective layers.
Continuous lengths of draw tapes are fed to the hem forming
stations concurrent with forming of the hems. The hems are
preferably formed about the draw tapes. The formed hems, with
the draw tapes incorporated therein, optionally traverse
stretching rollers which have working surfaces oriented at a
small angle to the direction of movement of the web. The formed
hems also optionally pass through electrostatic pinning
apparatus and/or through temperature control stations where the
temperature of the plastic web is controlled, such as with a
mist of water or a stream of air, to a desired temperature
before the hems are sealed.
The formed hems are then sealed to the main bodies of the
respective top and bottom layers. Optional second temperature
control stations can be employed downstream of the hem sealing
apparatus, to cool the web after the seals are formed. After
the hems have been sealed, the edge regions of the layers are
then rejoined, in face-to-face relationship with each other.
Preferred apparatus for rejoining the edge regions together is




2192642
-7- 29057 EPO
an upstanding cone, assisted by a horizontal turning bar
downstream of the upstanding cone. Air lubrication may be used
at one or more turning members, as beneficial for facilitating
rejoining the edge regions with each other.




2192642
-8- 29057 EPO
FIGURE 1 shows a representative block diagram of primary
work stations of equipment of the invention.
FIGURE 2 shows a representative pictorial view of the hole
forming station.
FIGURES 2A-2E show cross-sections of the edges of the web
at various stages in the process, and are taken at 2A-2A, 2B-2B,
2C-2C, 2D-2D, and 2E-2E of FIGURE 2.
FIGURE 3 shows a representative and fragmentary plan view
of the hole forming station.
FIGURE 4 shows a representative and fragmentary elevation
view of the hole forming station.
FIGURE 5 shows a side cross-section of a hole cutter used
in the invention.
FIGURE 6 shows an enlarged fragmentary view of the
separation station and the first hem forming station.
FIGURE 7 shows an enlarged fragmentary view as in FIGURE
6, with the web pulled back to illustrate the method of
initiating separation of the edge regions.
FIGURE 8 is a cross-section taken at 8-8 of FIGURE 2,
showing the separated edge regions at the hem sealing stations.
FIGURE 9 is a top view of equipment of the invention taken
at 9-9 in FIGURE 2, including a showing of the hem forming area
and the hem sealing area.
FIGURE 10 is a fragmentary end elevation taken at 10-10 of
FIGURE 2.
FIGURE 11 is a partial section taken at 11-11 of FIGURE 10.
FIGURE 12 is a cross section taken at 12-12 of FIGURE 2.
The invention is not limited in its application to the
details of construction and the arrangement of the components
set forth in the following description or illustrated in the
drawings. The invention is capable of other embodiments or of
being practiced or carried out in various ways. Also, it is to
be understood that the terminology and phraseology employed
herein is for purpose of description and illustration and should
not be regarded as limiting. Like reference numerals are used
to indicate like components.




2192642
'' -9- 29057 EPO
DETAILED DESCRIPTION OF. THE ILLUSTRATED EMBODIMENTS
Referring now by characters of reference to the drawings,
FIGURE 1 is a block diagram illustrating processing equipment
used in the invention. In general, a continuous plastic web I0,
generally a collapsed tube with top and bottom layers in
surface-to-surface contact with each other, is unwound at a web
unwind station 12 and is fed into a draw tape machine l4. The
web 10 is drawn through the draw tape machine 14 by nip rollers,
not shown, which are driven by conventional drive means, not
shown. The web 10 moves along a path having a general direction
as shown by the arrows 15 in the several FIGURES. See FIGURE
2. The plastic web 10 is slit in draw tape machine 14 at a
slitting station 16 to form top and bottom web layers 18, 20
having respective free edges 22, 24, such that the web at that
stage takes the form of being folded longitudinally along its
length, to form top and bottom layers. The web then passes to
a hole forming station 26 where holes 28 are punched in the top
and bottom layers adjacent the free edges 22, 24. Edge regions
34, 36 of the top and bottom layers 18, 20 are then separated
from each other at a separation station 38, immediately followed
by forming of the first and second hems 40, 42 in the separated
layers 18, 20 at respective hem forming stations 44, 46
traversing generally parallel but spaced paths while holding the
remainders of the widths of the top and bottom layers in
surface-to-surface contact with each other: The separated edge
regions generally lie in imaginary surfaces intersecting each
other along an imaginary line having a component extending in
the direction of travel of web 10. The hems are formed at edge
portions 48, 50 of the layers 18, 20, including the free edges
22, 24.
Concurrent with the forming of the hems 40, 42, continuous
draw tapes 52, 54 are fed from tape unwind stations 56, 58 to
the hem forming stations 44, 46, and the hems are formed about
the respective draw tapes 52, 54. The formed hems, with the
draw tapes incorporated therein, then optionally pass through
first temperature control stations 60 ,62, where the temperature
of the plastic web is controlled to a desired temperature. The




2 ~ 92642
-10- 29057 EPO
formed hems then pass to hem sealing stations 64, 66 where the
edge portions 48, 50 are sealed, generally at free edges 22, 24,
to the main bodies 68, 70 of the respective top and bottom
layers 18, 20, forming hem seals 72, 74.
The forming of the hem seals traps the draw tapes 52, 54
in the hems 40, 42. A narrow pressure wheel, described
hereinafter, applies pressure to the hot seal to improve the
seal quality. The sealed hems then optionally pass through
second temperature control stations 76, 78, where the
temperature of the plastic web is again controlled to a desired
temperature.
The formed and sealed hems, with the draw tapes therein,
then pass to the edge region rejoinder station 80, where the
first and second edge regions 34, 36 are rejoined, in face-to-
face relationship with each other, with the effect that the top
and bottom layers are again in surface-to surface contact with
each other over the entire transverse width of the web. The so
processed web has draw tapes 52, 54 securely trapped in the hems
40, 42. The web then passes out of draw tape machine 14, and
advances for further processing to e.g. a bag forming machine
82, where transverse heat seals and associated cuts are formed
across the web, forming bag side seals which seal the draw tapes
to the bags, and cutting individual bags from the continuous web
10.
Addressing a more detailed description of certain ones of
the elements, attention is first turned to the hole forming
station 26 and FIGURES 2-5. Hole forming station 26 includes
first turning bar 84, generally arresting downwardly-sloped
advance of web 10 and a second turning bar 86 generally turning
the web back to an upwardly-sloped path of advance. In-turn
plow 88, back-fold plow 90, and out-turning plow 92 operate on
the edge portions 48, 50 of the web as the web traverses the
hole forming station. In-turn plow 88 has a web contact surface
94 having a downwardly depending portion and a generally
horizontal portion. Back-fold plow 90 has a generally
horizontal web contact surface 96 comprising the bottom surface
of the back-fold plow. Out-turning plow 92 has a web contact
surface 98 having a generally horizontal portion and an upwardly




2192642
-11- 29057 EPO
depending portion. The downwardly depending portion of web
contact surface 94 of the in-turn plow forms an obtuse angle
°'AI" with the web contact surface 96 of back-fold plow 90. The
upwardly depending portion of web contact surface 98 of the out-
turning plow forms a similar obtuse angle "A2" with the web
contact surface 96 of back-fold plow 90. Angles "A1" and "A2°'
are generally equal, opposite, obtuse angles, measured from the
bottom surface of the back-fold plow, generally taken in
elevation view as in FIGURE 4.
In-turn plow 88 has an angled outer edge 100, adjacent the
free edges 22, 24 of the web which outer edge 100 extends
inwardly across the free edges of the web 10 along the direction
of travel of the web at an angle "A3" seen in plan view in
FIGURE 3. Back-fold plow 90 has a first angled inner edge 102
defining approximately the same angle "A3" With respect to the
free edges 22, 24 of the web 10. The angled inner edge 102 is
generally aligned with the outer edge 100 of the in-turn plow
88, and comprises a continuation of the generally horizontal
portion of the web contact surface 94.
Similarly, out-turning plow 92 has an angled outer edge
104, adjacent the free edges 22, 24 of the web which outer edge
104 extends outwardly across the free edges of the web 10 along
the direction of travel of the web at an angle "A4" seen in plan
view in FIGURE 3. Loci on outer edge 104 are generally aligned
with respective loci on outer edge 100 along the length of web
10, and thus at a common transverse distance from free edges 22,
24. Back-fold plow 90 has a second angled inner edge 106
defining approximately the same angle "A4" with respect to the
free edges 22, 24 of the web 10. The angled inner edge 106
intersects the inner edge 102 and is generally aligned with the
outer edge 104 of the out-turning plow 92, and comprises an
approximate continuation of the generally horizontal portion of
the web contact surface 98.
Back-fold plow 90 receives the in-folded edge portions and
folds the in-folded edges back onto a respective one of the main
body portions. A cutting notch 108 in back-fold plow 90
intermittently receives a hole former, namely cutter 110, which
cuts spaced holes 28, thus forming holes, in the edge portions



219262
-12- 29057 EPO
of the web as the edge portions pass through the hole forming
station 26.
FIGURES 2 and 6-8 illustrate detail of the separation
station 38, and the close cooperation of the separation station
38 with the hem forming stations 44, 46. Turning first to
FIGURES 2 and 6, as the web 10 leaves the hole forming station
26 the web travels along an upward path toward turning bar 112.
Separating plow 114 is mounted to turning bar 112 along the
path of travel of the web 10, thus in part guiding the web in
its upward travel. Separating plow 114 has a separating edge
116 angled inwardly along the direction of travel of the web.
Separating edge 116 engages a progressively increasing portion
of edge region 36 of the bottom layer as the web travels across
the top surface 118 of the separating plow 114 toward turning
bar 112, turning the edge region 36 in a downwardly directed
path, relative to layer 18 and to the remainder of the bottom
layer 20.
As the primary portion of the bottom layer 20 turns about
turning bar 112, the edge region 36 of the bottom Layer moves
into a vertical orientation. The remainder 120 of the bottom
Layer (namely the above mentioned "primary portion") is in a
horizontal orientation, disposed at more or less 90 degrees to
the edge region 36. The relative vertical orientation of the
edge region 36 and the respective horizontal orientation of the
remainder 120 of the bottom layer are illustrated in FIGURE 8,
where it is seen that the remainder 120 of the bottom layer 20
is in surface-to-surface contact with the remainder 122 of the
top layer 18.
It is contemplated that the edge region 36 could readily
adopt orientations other than vertical. Thus, the included
angle "A5" (FIGURE 8) may be as small as about 30 degrees, or
as large as 160 degrees, potentially up to nearly 180 degrees.
Any and all angles in between are contemplated as possible,
though angles closer to 90 degrees, such as between 75 and 105
degrees are contemplated as being most preferred.
Folding plow 124 is mounted along the path of travel of the
web 10, beside separating plow 114. The top surface 126 of
folding plow 124 forms a generally common surface with the top



2192642
-13- 29057 EPO
surface 118 of separating plow 114. Accordingly, the top layer
18 of web 10 is supported over a generally common top surface
defined by the top surface of separating plow 114 and top
surface 126 of folding plow 122, in combination, which top
surfaces are aligned with the outer radius of turning bar 112.
Folding plow 124 and separating plow 114 are separated by slot
128 which receives the edge region 36 of bottom layer 20 as the
edge region 36 turns downwardly toward the vertical orientation
seen in FIGURE 8.
Hem folding plow 124 has a folding edge 130 extending
across and progressively inwardly of the free edge 22 of the top
layer 18, up to the level of the top of turning bar 112. The
folding edge progressively folds the edge portion 48 downwardly
as the web progresses along folding edge 130, such that the free
edge 22 is disposed generally downwardly as edge region 34
passes over the top edge 132 of the folding plow 124.
Hem folding plow 124 further has an aperture 134, and a
small turning roll 136 journalled in the aperture 134. The
turning roll 136 has an outer working surface generally aligned
with the upwardly sloped top web-engaging surface 126.
Hem forming plow 138 has a generally horizontal surface 140
extending along the path of travel of the top layer 18, disposed
at an angle obtuse to top surface 126 of plow 124, downstream
of turning bar i12, separating plow 114 and folding plow 124,
and generally level with the top of turning bar 112 and the top
edge 132 of hem folding plow 124. The top surface 140 has an
angled leading edge 142. An associated upstanding inner surface
144 extends inwardly across the free edge 22 of the top layer
18 when viewed along the direction of travel of the web 10, all
as seen in FIGURES 2, 6 and 7. The edge portion 48 of top layer
18, which is down-turned at hem folding plow 124, engages the
upstanding inner surface 144 and rides-up and over leading edge
142. The oblique angle of leading edge 142 folds the already
down-turned free edge 22 upwardly under the main body portion
68 of the layer 18, thus forming the hem 40.
As referred to herein, each layer 18, 20 has two main
elements defined across the width of the respective layer,
namely an edge region (34 or 36) and a remainder portion (120



2192642
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or 122). Each edge region includes an edge portion and a main
body portion. The edge portion is that portion of the edge
region which is folded under at e.g. hem forming plow 138. The
main body portion is all the rest of the respective edge region.
Each edge portion includes the respective free edge (22 or 24).
Each hem (40 or 42) is formed from the respective edge portion
and an adjoining part of the respective main body portion, with
the hem seal typically being formed at or near the respective
free edge 22 or 24 on the edge portion.
While the hem 40 is being formed as described above, draw
tape 52 is being fed from unwind station 56 through aperture
134, over turning roll 136, and into contact with the underside
of top layer 18 as it progresses onto the top surface 126 of
folding plow 124. Thus, the draw tape 52 advances into the hem
forming operation along a path generally parallel in place to
the path of the plastic material of layer 18, and in parallel
in time with the folding of the edge portion by the hem folding
plow. The draw tape advances between the top surface 126 of the
hem folding plow and the underside of the layer 18, thence
advancing together with the edge portion 48 of layer 18 across
the top edge 132, past leading edge 142, and across the top
surface 140 of hem forming plow 138.
As draw tape 52 approaches the leading edge 142, it is
drawn into close proximity with the edge portion 48 of the top
layer 18. The draw tape, itself, is in a horizontal
orientation, extending along the length of the free edge 22 of
the layer 18. As the leading edge 142 of the hem forming plow
138 folds the edge portion 48 of top layer 18 upwardly against
the main body portion 68 of the top layer in forming the hem 40,
the edge portion 48 enfolds the draw tape 52 between the edge
portion 48 and the main body portion 68. Thus, the edge portion
is folded about the draw tape, whereby the hem is formed about
draw tape 52 in the process of incorporating the draw tape into
the hem. In the process, the edge region 34 is maintained as
a generally straight line extension of the remainder of the
width of the top layer 18.
The edge portion 48 is somewhat wider, measured across the
width of the web 10, than the draw tape 52. Thus, when edge




2~ 92642
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portion 48 is folded up against main body portion 68, the free
edge 22 extends past the full width of the draw tape and is in
surface-to-surface contact with the main body portion 68 away
from the folded edge 158 of the edge portion 48. The
relationship of the draw tape in the folded edge portion is
shown in detail in FIGURE 8.
Endless support belt 146 is mounted for support and endless
traverse under hem 40 downstream from hem forming plow 138 past
electrostatic pinning device 154 and hem sealing device 156, to
pressure wheel 178. Support belt 146 is mounted on a plurality
of guide rolls 148 about an endless path. The guide rolls 148
are shown in FIGURE 2. The downstream one of the guide rolls
148 provides support against which pressure wheel 178 presses.
Support belt 146 is driven by conventional drive, not shown, at
a surface speed matching the speed of advance of the web 10 at
edge portion 48. Thus, the support belt moves with the hem
thereon from approximately the hem forming plow to pressure
wheel 178.
Support belt 146 is preferably rather flexible and can be
made of, for example, reinforced polymer such as various natural
and synthetic rubbers or other polymers or copolymers, or the
like. Belt 146 may, of course, include conventional additives
for controlling surface characteristics such as slip and the
like. Examples of such additives are the silicones and
fluorinated polyethylenes, such as polytetrafluoroethylene, also
known as Teflon °.
Downstream of the hem forming plow, the edge portion 48
passes under stretching roll 152, thence electrostatic pinning
device 154, subsequently first temperature control device 60,
and heat seal device 156.
Support bar 150 underlies and supports support belt 146
along the portion of the path which passes under the
electrostatic pinning device, and the heat seal device. Support
bar 150 is stationary, and physically supports support belt 146
against physical downward forces.
Support bar 150 is electrically conductive, and is
electrically grounded, whereby the support bar 150 presents an
electrical ground cooperative with the electrostatic pinning




2~ 9242
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device 154 for electrostatically pinning the non-conductive
material of the plastic web 10 to moving support belt 146 after
the edge portion 48 has been stretched by stretching roll 252.
Support bar 150 is preferably metal or other suitably rigid
conductive material.
Stretching roll 152 is mounted over the edge portion 48 at
a slight angle to the direction in which the web 20 is moving,
and presses downwardly against the edge portion 48, with the
edge portion 48 being supported by resiliently flexible support
belt 146. Thus, the primary working surface of stretching roll
152 is disposed at a slight angle (e. g. less than 20 degrees,
for example about 5 degrees to about 10 degrees) to a
perpendicular e.g. line 155 extending transversely across the
web 10. Stretching roll 152 works against primary resistance
of support belt 146, which can be pushed down slightly by roller
152, as the hem traverses from the hem forming element to the
hem sealing element. Working against resilient underlying
support belt 146, roll 152 controls transverse positioning of
the formed hem with respect to sealing device 156, while the hem
seal is being formed. Thus, the web moves freely transversely
in removing wrinkles and the like until support belt 146 reaches
support bar 150 in the vicinity of electrostatic pinning device
154.
Accordingly, the force exerted against the edge portion 48
urges the edge region 34 of layer 18 outwardly with respect to
the web, stretching the web in the transverse direction and
pulling wrinkles out of the film. At the same time, stretching
roll 152 squeezes out air from between the edge portion 48 and
main body portion 68 inside the formed hem 40.
Electrostatic pinning device 154 is mounted proximately
downstream of the stretching roll 152 immediately after the
stretching at stretching roll 152, over the edge portion 48.
Pinning device 154 electrostatically pins the edge portion 48
against the moving support belt 146. The electrostatic pinning
device thus effectively pins the edge portion 48 of stretched
layer 18 to the moving belt 146 for the full length of the
support bar 150, substantially from a point slightly downstream
of the stretching roll 152 until after the hem seal 72 has been




2192642
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formed at sealing device 156 and pressure wheel 178 and
set/cooled at the second temperature control device 76. Thus,
the pinning device fixes the layer against transverse movement
while the hem seals are being formed and set.
Heat seal device 156 is mounted downstream of electrostatic
pinning device 154, over edge portion 48,~ and positioned
approximately over the folded-under free edge 22 of the top
layer. Heat seal device 156 can be any of the conventionally
known heat seal devices which form heat seals on continuously
moving plastic webs. As the edge portion 48 passes under the
heat seal device, both the edge portion 48 and the main body
portion 68, of edge region 34, are being supported by support
belt 146. A stream of hot air from the heat seal device heats
the main body portion 68 adjacent free edge 22, softening both
the main body portion and the free edge, and forming bonds
therebetween in creation of heat seal 72 along a line, extending
along the length of the web, between the main body portion 68
and the edge portion 48 at or adjacent free edge 22. Other
types of heat seal devices could be used, such as infrared
heaters.
Pressure wheel 178 then exerts modest downward pressure on
the softened materials to fuse, and thus bond the softener
materials to each other.
First device 60 is mounted proximately downstream of the
pinning device 154, over main body portion 68, which is over
edge portion 48. The temperature control device 60 projects
cooling (or heating) fluid such as cooling (or heated) air or
a mist or stream of water onto the main body portion 68
immediately prior to the combination of the main body portion
and the edge portion passing under the heat seal device 156.
Thus, the temperature control device 60 imparts a predictable,
controlled temperature at the edge portion 48 immediately
upstream of hem seal forming at heat seal device 156.
Second temperature control device 76 is mounted proximately
downstream of the heat seal device 156 and downstream of
pressure wheel 178, over main body portion 68 at edge portion
48. The temperature control device 76 projects cooling fluid
such as cooling air or a mist or stream of water onto the main



2192642
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body portion 68 shortly after the main body portion and the edge
portion pass under the pressure wheel 178. Thus, the
temperature control device 76 provides cooling to the seal 72
to set the seal and cool the seal thus to avoid residual heat
inadvertently bonding portions of the web to each other
downstream of the pressure wheel 178.
The remainders 120, 122 of the layers remain in surface-to-
surface contact with each other over the entire path traversed
by the web through the draw tape machine. Between turning bar
112 and turning bar 162 the remainders 120, 122 of the layers
are supported by a support table illustrated generally by the
element 159 (FIGURE 8). At the end of the support table, the
remainders 120, 122 traverse a turn of about 45 degrees over
turning bar 162. Turning bar 162 is hollow as illustrated in
FIGURE 12, having an inner chamber 165 therein, and being closed
at both ends. A row of air ports 167 extends from the inner
chamber 165, through the outer wall of bar 162, to the outer
surface of the turning bar, at about 22 degrees, trailing, from
the top of turning bar 162. Low pressure compressed air is fed
into the inner chamber 165 by an air line, and out the air ports
167 to provide a lubricating air cushion positioned generally
mid-way along the path of turning contact between the bottom
layer 20 and turning bar 162, to assist the turning of the
remainders 120, 122 about the turning bar 162.
Turning bar 162 is mounted downstream of the second
temperature control device 76. Turning bar 162 extends from
generally the back edge 163 of the support table 159 to edge
region 34, and thus stops well short of edge portion 48. Thus,
edge portion 48 is not supported by turning bar 162.
Turning plate 168 has a rounded vertical edge 174, and a
rounded horizontal turning edge 176. Turning edge 176 has a
radius of curvature generally corresponding to the working
surface of turning bar 162, and functionally comprises an
extension of turning bar 162, along edge region 34. The turning
bar 162 ends remote from edge portion 48. A gap 164 is disposed
between the turning bar 162 and the turning edge 174 of turning
plate 168. Rejoinder turning roll 166 is a second turning



2192642
. ,
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member, and is positioned downstream of, and is vertically
downwardly displaced from, turning bar 162 and turning edge 176.
The entirety of top layer 18 passes over the functional
combination of turning bar 162 and turning edge 176 and passes
downwardly under rejoinder turning roll 166. The remainder 120
of bottom layer 20 passes over turning bar 162 while the
vertically downwardly disposed edge region 36 passes through gap
164, about vertical turning edge 174, and over upstanding
turning cone 170. Turning cone 170 engages the edge region 36
(FIGURES 2, 11, and 12) directly downstream of the turning edge
174 and turns the edge region 36 gradually over the conical
surface of cone 170 from a vertical orientation toward a more
horizontal orientation, such that the edge region 36 leaves the
turning cone disposed at an angle of about 40-50 degrees (FIGURE
10), preferably 45 degrees, from the vertical. The edge region
36 continues the transition toward a horizontal orientation as
it moves toward rejoinder turning roll 166. Edge region 36
finally reaches a horizontal orientation as it passes under
turning roll 166, simultaneously rejoining edge region 34 of top
layer 18.
FIGURES 10 and 11 show some detail of the process as the
edge region 36 achieves a full 90 degree turn, which may be
considered an edge rotation over a distance travelled, from
vertical to horizontal as it passes over turning cone 170. Edge
region 36 makes the rotation around turning cone 170 and joins
edge region 34 of the top layer 18 at rejoinder turning roll
166.
At rejoinder turning roll 166, the web 10 comprises the
full widths of top and bottom layers 18, 20, with draw tapes 52,
54 in the sealed hems 40, 42. The web 10 passes from turning
roll 166 to a driven nip, not shown, and then out of the draw
tape machine 14, to bag forming station 82 which forms e.g.
transverse heat seals and cuts in the web to seal the bag sides
and cut individual bags from the continuous web.
While not shown in the same detail as above, draw tape 54
is incorporated into the hem 42 in bottom layer 20 using like
steps. Thus, the tape incorporation process at bottom layer 20
uses a folding plow 124 including aperture 134, a forming plow




2192642
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138 including surfaces 140, 144, and angled leading edge 142,
incorporating draw tape 54 into the hem 42, as well as a
stretching roll 152, an electrostatic pinning device 154, first
and second temperature control devices 60, 76, heat seal device
156, and pressure wheel 178.
While included in the preferred embodiment illustrated,
temperature control devices 60, 76 are optional, and either such
temperature control device may be used alone, or the control
devices 60, 76 may be used together. The exact location of the
temperature control devices can vary and still have the same
effect.
Returning now to FIGURES 6 and 7, and looking downstream
along the processing line, the top left corner of separating
plow 114 and the top right corner of folding plow 124 define a
separating notch 172 therebetween. Specifically, notch 172 is
defined by upper facing edges of the respective plows which
converge downwardly toward each other along the slot 128. In
some embodiments, the slot 128 should be widened at the notch.
Thus, an insert, not shown, is preferably added at the top edge
e.g. at 132, where the top and bottom folding plows 124 meet.
With the notch properly dimensioned, the notch causes automatic
initiation of feeding of the edge region 36 of bottom layer 20
through slot 128 while feeding the edge region 34 transversely
over hem folding plow 124. Thus, for use with e.g. low density
polyethylene bag material having a thickness of about 0.001 inch
each layer, one embodiment of the notch has an opening at its
top of about 0.19 inch, an angle at the insert of about 60
degrees from horizontal, and a depth, from the widest to the
narrowest opening represented by the notch 172, of about 0.33
inch.
FIGURE 7 illustrates the method of starting the bottom edge
region 36 feeding downwardly through the slot 128. With the
plastic web 10 being driven slowly along the processing line,
under tension, such as at about 15 to about 600 feet per minute,
the operator pushes the edge region 36 of bottom layer 20 across
the separating notch while keeping the edge region 34 extended
across slot 128, and across folding plow 124. The edge region
36 is thus bunched up adjacent the notch as shown by the shaded




2 i 92642
-21- 29057 EPO
area 173 of the web in FIGURE 7. It should be noted that, in
FIGURE 7, part of the edge portion 34 of top layer 18 is shown
in dashed outline, showing underlying layer 20 in full line
drawing.
The operator then releases the edge region 36, preferably
with the web still moving along the processing path, and
allowing the bunched-up edge region 36 of bottom layer 20 to
gradually move transversely back toward the notch as the web
continues to advance under draw tension.
As the edge region 36 moves back toward the notch 172, the
edge of the bottom layer begins feeding downwardly into the
notch 172. As the web continues to advance, the edge region 36
becomes fully deployed through notch I72, resulting in
subsequent smooth feeding of the edge region 36 downwardly
through the notch in the continuous feed process characteristic
of the equipment of the invention. This provides a fast, easy
way to thread the hem forming station 46. The edge region 36
can, of course, be threaded through slot 128 by hand, with or
without forward driving of the web 10.
FIGURES 2A, 2B, 2C, 2D, and 2E illustrate the
configurations of the edges of the web at various stages of the
process. Thus, FIGURE 2A shows the free edges 22, 24, and thus
the edge portions 48, 50, after the slitting operation,
overlying each other at the beginning of the process of forming
the hems and incorporating the draw tapes thereinto.
FIGURE 2B shows the edge portions 48, 50 folded back onto
the main body portion 68 of the top layer, with holes 28 having
been simultaneously cut in both layers by the hole cutter 110.
Folded-over edge portion 48 of top layer 18 is nested inside
folded-over edge portion 50 of bottom layer 20.
FIGURE 2C shows the edge portions after being unfolded to
the flat condition at out-turning plow 92.
FIGURE 2D shows the edge portions 48, 50 re-folded,
inwardly against the main body portions 68, 70 and with the draw
tapes 52, 54 received therein.
FIGURE 2E shows the edge portions 48, 50 after the edge
regions have been rejoined at turning roll I66. The edge
regions 34, 36 are again overlying each other, with the hems

CA 02192642 2004-12-13
-22-
formed, sealed, and facing each other, and with the draw tapes
secured therein by the seals 72.
It is contemplated that the operation and functions of the
invention have become fully apparent from the foregoing
description of elements, but for completeness of disclosure the
usage of the invention will be briefly described.
A flattened tubular web 10 having opposing edges is unwound
from web unwind station 12 and fed to the draw tape machine 14.
As the flattened web 10 enters the draw tape machine 14, it is
slit at one of the edges to form free edges 22, 24, which will
be disposed at the tops of the bags to be fabricated from the
web 10.
The web, still in a generally flat disposition, then
advances downwardly.toward the hole forming station 26. As the
web advances toward turning bar 84, the top layer is in
overlying contact with the bottom layer. The slit free edges
22, 24 pass under in-turn plow 88 at web contact surface 94, and
both free edges 22, 24 are folded upwardly about edge 100, as
the main body of the web passes around turning bar 84 at an
obtuse angle, to a horizontal disposition, and edge portions 48,
50 pass toward the back-fold plow 90. The edge portion 48 is
nested inside edge portion 50. The upwardly folded edge
portions 48, 50 are engaged by inner edge 102 of back-fold plow
90 and are folded back to a 180 degree orientation with respect
to the main body portion 68 of the top layer.
With both edge portions 48, 50 folded back 180 degrees onto
main body portion 68, the edge portions pass along the web
contact surface 96 of back-fold plow 90, and through cutting
notch 108. Cutter 110 cuts holes in the back-folded edge
portions at spaced locations along the length of the web as the
web advances through the cutting notch. Suitable cutter 110,
and operation of such cutter, are taught in United States Patent
4,664,649 Johnson et al.
As the web advances past the cutting notch, the folded edge
portions 48, 50 are unfolded by operation of inner edge 106 of
back-fold plow 90 in combination with outer edge 104 of out
turning plow. The folded edge portions are turned generally
into a vertical orientation as they leave inner edge 106 and as




2192642
-23- 29057 EPO
the main body of the web passes about turning bar 86 at an
obtuse angle and begins advancing upwardly. As the edge
portions are engaged by outer edge 104 the edge portions are
fully unfolded such that the edge portions 48, 50 are restored
to their generally flat condition as e.g. straight line
extensions of the remainders 120, 122 of the respective layers
18, 20. FIGURE 2 illustrates the holes 28 in the web at the
edge portions after traversing the hole forming station.
The advancing web next encounters the separating plow 114,
and at about the same time hem folding plow 124. The edge
region 36 of bottom layer 20 passes downwardly through the slot
128 between the folding plow 124 and the separating plow 114.
The edge region 34 of the top layer advances over the top
surface 126 of folding plow 124. The edge region 36
concurrently advances over a corresponding folding plow (not
shown) below the level of support table 159.
The rest of the description here will describe the folding
and sealing steps only with respect to the top layer 18.
However, like steps also are performed with respect to the
_ bottom layer 20.
As the edge portion 48 advances over the folding plow 124,
the edge portion 48 is folded vertically downwardly by trailing
folding edge 130. The downwardly depending edge portion 48 is
engaged by the leading folding edge 142 of hem forming plow 138,
and folded upwardly against and onto the main body portion 68
of the layer, thus completing formation of the hem 40.
As the hem 40 is being folded, draw tape 52 is fed around
turning roll 136, out of the hem folding plow 124 at aperture
134, between the main body portion 68 of layer 18 and the top
surface 126 of the folding plow. As the hem 40 is being formed,
the draw tape 52 is fed over the leading edge 142 and across the
top surface 140 of hem forming plow 138. Thus, as the
downwardly depending edge portion 48 is folded upwardly against
and onto the main body portion 68, the edge portion 48 is folded
under the draw tape 52 which is advancing across the top surface
140. Thus, the upward folding of the edge portion 48 against
the main body portion 68 engages the draw tape 52 between the
edge portion and the main body portion 68, with free edge 22



2~ X2642
-24- 29057 EPO
extending beyond the draw tape 52 and engaging the main body
portion 68 in surface-to-surface contact (FIGURE 8).
With the hem thus formed, the hem is passed under
stretching roll 152 where any wrinkles or the like are stretched
out of the edge region 34. With the edge region stretched, the
edge portion is then electrostatically pinned to the support
belt 146, with support bar 150 cooperating in providing the
electrical pinning force. The support belt 146 moves at the
same linear speed as the web 10, whereby the support belt moves
along generally carrying the edge portion 48 through the rest
of the hem fabrication steps.
The stretched, pinned edge region then passes under the
first temperature control station 60 where a controlled
temperature fluid is imposed against the edge portion, such as
air, or atomized water e.g, a water mist, cooling or heating the
edge region as appropriate to provide a predetermined
temperature to the edge region in preparation for the step of
forming heat seals at heat seal device 156 and pressure wheel
178, sealing the formed hems.
The temperature controlled edge region then passes to the
hem seal station 64 at heat seal device 156. Concentrated heat
such as hot air is applied to the main body portion of the web
opposite the free edge 22, softening the main body portion and
the adjacent elements of the edge portion, preferably at the
free edge. The facing lines of softened material in main body
portion 68 and edge portion 48 then pass under pressure wheel
178 which presses against the rear guide roller 148, as shown
in FIGURES 2 and 9. The pressure urges the lines of heat
softened material together in bonding contact, such that the
continuous-line seal 72 is formed between the edge portion 48
and the main body portion 68. Thus is formed heat seal 72,
joining the free edge and the main body portion, and thus
closing and sealing the hem along the continuous line.
The sealed hem then passes under the second temperature
control station 76 where a controlled temperature fluid, such
as air, or atomized water e.g. water mist, is again imposed
against the edge portion, cooling the edge region so that the



2192642
-25- 29057 EPO
plastic is not inadvertently bonded to itself at unintended
locations.
After cooling, the layer 18 passes over turning bar 162 and
downwardly under turning roll 166. Meantime, the edge region
36 of the bottom layer, also hemmed, sealed, and cooled, passes
about vertical turning edge 174, turning cone 170, and turning
roll 166 in the process of rotating from its downwardly
extending vertical orientation to a horizontal orientation. The
edge regions 34, 36 are rejoined in surface-to-surface contact
with each other at turning roll 166, and then proceed through
the above-mentioned driven nip.
The web, having been hemmed, the draw tapes 52, 54
incorporated into the hems, the hems sealed, and the edge
regions rejoined to each other, the web passes out of the draw
tape machine for further processing steps which form no part of
this invention.
Those skilled in the art will now see that certain
modifications can be made to the apparatus and methods herein
disclosed with respect to the illustrated embodiments, without
departing from the spirit of the instant invention. And while
the invention has been described above with respect to the
preferred embodiments, it will be understood that the invention
is adapted to numerous rearrangements, modifications, and
alterations, and all such arrangements, modifications, and
alterations are intended to be within the scope of the appended
claims.

Representative Drawing
A single figure which represents the drawing illustrating the invention.
Administrative Status

For a clearer understanding of the status of the application/patent presented on this page, the site Disclaimer , as well as the definitions for Patent , Administrative Status , Maintenance Fee  and Payment History  should be consulted.

Administrative Status

Title Date
Forecasted Issue Date 2006-02-14
(22) Filed 1996-12-11
(41) Open to Public Inspection 1997-07-03
Examination Requested 2001-10-22
(45) Issued 2006-02-14
Expired 2016-12-12

Abandonment History

There is no abandonment history.

Payment History

Fee Type Anniversary Year Due Date Amount Paid Paid Date
Application Fee $0.00 1996-12-11
Registration of a document - section 124 $0.00 1997-03-13
Maintenance Fee - Application - New Act 2 1998-12-11 $100.00 1998-09-15
Maintenance Fee - Application - New Act 3 1999-12-13 $100.00 1999-11-25
Maintenance Fee - Application - New Act 4 2000-12-11 $100.00 2000-09-13
Request for Examination $400.00 2001-10-22
Maintenance Fee - Application - New Act 5 2001-12-11 $150.00 2001-11-19
Maintenance Fee - Application - New Act 6 2002-12-11 $150.00 2002-11-22
Maintenance Fee - Application - New Act 7 2003-12-11 $150.00 2003-10-01
Maintenance Fee - Application - New Act 8 2004-12-13 $200.00 2004-11-05
Final Fee $300.00 2005-11-10
Maintenance Fee - Application - New Act 9 2005-12-12 $200.00 2005-11-28
Maintenance Fee - Patent - New Act 10 2006-12-11 $250.00 2006-12-05
Maintenance Fee - Patent - New Act 11 2007-12-11 $250.00 2007-10-30
Maintenance Fee - Patent - New Act 12 2008-12-11 $250.00 2008-10-09
Maintenance Fee - Patent - New Act 13 2009-12-11 $250.00 2009-11-17
Maintenance Fee - Patent - New Act 14 2010-12-13 $250.00 2010-11-03
Maintenance Fee - Patent - New Act 15 2011-12-12 $450.00 2011-10-13
Maintenance Fee - Patent - New Act 16 2012-12-11 $450.00 2012-10-31
Maintenance Fee - Patent - New Act 17 2013-12-11 $450.00 2013-11-13
Maintenance Fee - Patent - New Act 18 2014-12-11 $450.00 2014-12-05
Maintenance Fee - Patent - New Act 19 2015-12-11 $450.00 2015-12-03
Owners on Record

Note: Records showing the ownership history in alphabetical order.

Current Owners on Record
CMD CORPORATION
Past Owners on Record
DUTTER, TIMOTHY R.
GIETMAN, PETER J., JR.
JANSEN, THOMAS C.
SELLE, PAUL A.
SLAMA, FRANK M.
Past Owners that do not appear in the "Owners on Record" listing will appear in other documentation within the application.
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Document
Description 
Date
(yyyy-mm-dd) 
Number of pages   Size of Image (KB) 
Representative Drawing 1997-09-02 1 24
Claims 1997-04-18 50 2,113
Description 1997-04-17 24 1,306
Drawings 1997-04-17 8 156
Cover Page 1997-07-04 1 19
Abstract 1997-04-17 1 37
Cover Page 2006-01-10 1 59
Description 2004-12-13 24 1,304
Claims 2004-12-13 50 1,742
Representative Drawing 2005-05-04 1 16
Assignment 1996-12-11 14 647
Prosecution-Amendment 2001-10-22 1 42
Prosecution-Amendment 2002-01-09 1 35
Prosecution-Amendment 2004-06-16 2 62
Prosecution-Amendment 2004-12-13 55 1,964
Correspondence 2005-11-10 1 32