Note: Descriptions are shown in the official language in which they were submitted.
S~
The invention relates to a deep-drawing machine for manufacturing
containers or receptacles made out of thermoplastic foil matcrial which in-
cludes an arrangement for introducing sections of banderole-shaped strips into
the hollow molds prior to the deep drawing step.
A deep-drawing machine of -this type permits an economic and hygienic
packaging of substances in liquid or pasty form, for example, medications or
food stuff. For this purpose, the deep-drawing machine includes means for
manufacturing the container, means for fil~ng the container and means for
sealing it. Furthermore, there are means provided to affix onto the container,
for exanple, decorative material, by means of a banderole-like strip which is
connected to the exterior wall of the container and is permanently bonded to
it by means of being sealed thereon.
A deep-drawing machine of this type is, for example, disclosed in
German published patent application No. 23 65 028. In this known deep-drawing
machine the arrangement for inserting the banderole-like strip sections into
the hollow mold encompasses a slidably axially movable winding mandrel which
serves to act on the banderole-like strip sections. The winding mandrel pro-
jects in a first position completely into the hollow mold, whereas in its other
second position its front end forms the bottom of the mold during the forming
process.
In particular, with a rotatable winding mandrel with a circular
surface and a container shape which departs from the conventional cylindrical
shape (such container shape can, for example, have an elliptical cross-sectional
surface in the edge vicinity) there arise certain problems when introducing
the banderoles. Such problems exhibit themselves, for example, in that over-
lapping end portions of the banderole during the deep-drawing of the container
is displaced in a direction towards the bottom of the mold and thereby no
_ I
longer remains at the same heigh-t as the initial portion of the
banderole. ~uch a banderoled container is, however, used as scrap.
It is an object of this invention to improve known deep-
drawing machines of the above type in such a way that the afore-
described prob]ems are avoided and an error-free banderoling is
achieved.
The invention provides a deep drawing machine for manu-
facturing containers from thermoplastic sheet material by deep
drawing followed by pressure forming in a hollow mold, said machine
including insertion means for positioning a banderole-shaped s-trip
section into the hollow mold prior to deep drawing of the sheet
material, whereby when -the container is formed by means of a pres-
sure medium applied -to the interior thereof the strip section is
sealed onto the outer surface of the container: wherein said
insertion means cornprises a winding mandrel having a profile that
corresponds to the interior of said hollow mold to be received
therein with a clearance that defines a guide channel around the
winding mandrel; the guide channel portion of the outer peripheral
surface of the mandrel having a plurality of openings -therein tha-t
are adapted to be placed in communication with a vacuum source;
means for feeding said s-trip sec-tion endwise into said guide
channel and around said winding mandrel; means to apply vacuum to
said openings to draw the strip section against -the surface of
said winding mandrel; means to move said hollow mold axially with
respect to said winding mandrel to posi-tion said strip section at
a predetermined axial location within said hollow mold; means for
releasing said strip section from said mandrel and means for engag-
ing it to said hollow mold at said predetermined location.
-- 2
The inven-tion is here:inafter further described, by way
of example only, in conjunction with the drawings, in whicho
Figure 1 is a schematic cross-sectional view in the
region of the
- 2a -
s~
hollow molds of the deep-drawing machine in which all parts of the arrangement,
which are not immediately related to the invention, have been omitted, which
cross-sectional view is along line B-B of Figure 2;
Figure 2 is a longitudinal sectional view along .~-A o~ Pigure l;
Figure 3 is a plan view of the upper side of the glidably mounted
slider;
Figure 4 is a cross-sectional view of the glidably mounted slider
along line C-C of Figure 3;
Figure 5 is a partial view of the glidably mounted slider viewed in
the direction in which the banderole-shaped strip section is introduced;
Figure 6 illustrates a first embodiment of a cutting arrangement for
cutting the banderole-shaped strip sections;
Figure 7 illustrates a further embodiment of a cut~ing arrangement
for cutting the banderole-shaped strip sections; and
Figure 8 is a cross-sectional view of a plurality of hollow molds
arranged side-by-side in the cutting plane s-s according to Figure 2.
The principle of manufacturing of containe-rs having banderole-shaped
strips in a deep-drawing machine is already known. The banderole-shaped strip~
which can serve for decorative or reinforcement purposes~ is inserted in a
hollow mold, a thermoplastic preheated foil is placed over the open side of the
hollow mold, and with the aid of a punch the thermoplastic foil is shaped
while being introduced into the hollow mold and thereby is shaped into a con-
tainer. For final shaping the container receives the necessary shape by means
of a pressure medium which acts on the punch side on the preshaped con~ainer
and presses its walls against the in~er surface of the hollow mold. The foil
of the container is thus fixedly joined to the banderole-strip which has been
previously introduced into the hollow mold.
:
s~
In order to make possible the insertion of the banderole-sha~ed
strip into the hollow mold there is provided in the known deep-drawing machines
a rotatable winding mandrel which brings the banderole-shaped strip into a
shape which is adapted to that of the container and then transfers the strip
into the hollow mold.
The arrangement of this invention departs from the aforedescribed
conventional arrangement in that a non-rotatable winding mandrel 1~ is provided
(see Figure 1)~ which is fixedly arranged relative to the axially movable
hollow.mold 1l. Outside of the hollow mold 11 there is mounted at the inlet
side of the banderole-shaped strip sections 10 a slider 16 which is glidably
mounted relative to the hollow mold 11 and the winding mandrel 12 (see Figures
3 to 5). This slider 16 has a plurality of recesses 17 the height of which
correspond to the width of the banderole-shaped strips 10. In order to facilit-
ate the introduction of the banderole-shaped strips 10 i.nto the recesses 17,
the recess is advantageously widened by a funnel-shape at the side confronting
the exterior surface 18 of the slider 16 which faces away from the hollow mold
11 .
The glidable movement of the slider 16 is effected perpendicular to
the plane of the banderole-shaped strip 10 and in a plane which is parallel to
the path, (not shown) traversed by the foil and from which the containers are
manufactured.
The glidably mounted sliders 16 are alternatively movable between
essentially two operative positions~ whereby in the first operati~e position of
the slider 16 the recess 17 is in alignment with the inlet channel l9 for the
banderole-shaped strip sections 10 in the hollow mold 11 and whereby in the
second operative position of the slider 16 the recess 17 is disposed at the
level of the openings 15 in the exterior peripheral surface of the winding man-
-- 4 -
drel 12. In order to limit the respecti~e operative positions of the slider
16, the latter has two stops 20, 21 projecting in the direction of the hollow
mold 113 which serve to abut against the exterior surfaces 22, 23 of the hollow
mold 11 and in this manner limit the further movement of the slider 16 from
its respective operative position. At least one adjustable screw 39, mounted
in the stop 21 where it can be fixed in position, serves to exactly adjust the
working positions of the glidably mounted slider 16.
The inserting of the banderole-shaped strip 10 into the hollow mold
11 is carried out as follows:
The slider 16 is disposed in its first working position, in which
the recess 17 is in alignment with the inlet channel 19. This operative
position of the slider 16 is limited by the stop 219 which abuts against the
exterior surface 23 of the hollow mold 11. The hollow mold 11, which is movable
relative to the fixed winding mandrel 12 in the axial direction, su~rounds in
its first working positioll the winding mandrel 12 coaxially in such a way
that there is formed between the inner wall 33 of ~he hollow mold 11 and the
exterior wall 34 of the winding mandrel 12 a guide chalmel 35 for the banderole-
shaped strips 10.
The banderole~shaped strips 10 are paid out from a supply roller (not
shown~ and by suitable means, for example3 bilaterally disposed drive rollers
27 acting on the strip 10, is preferably guided step-wise through the recess
17 and the inlet channel l9 in such a way into the guide channel 35 that it
abuts against the exterior curved surface 34 of the winding mandrel 12. In
order to facilitate the introduction of the banderole-shaped strips 10, the
glidably motmted slider 16 has a nose-shaped projection 16' which projects nor-
mally from the exterior surface 18' of the slider 16 facing the winding mandrel
12. This projection 16' is clearly visible from an examination of ~igures 3
-- 5 --
and 4. The banderole-shaped strip 10, which is introduced into the recess 17
is slidingly guided along the exterior surface ~0 of the projection 16'. The
winding mandrel 12 has at its disposal a cut-out ~1 at the level and depth of
the projection 16 for the purpose of not hindering the movement of the slider
16 between its different operative positions. The forward end of the strip 10
thus reaches the region of the exterior glide surface 3~ of the winding mandrel
12 wherein a bore 14 is arranged which is in communication via a conduit 13'
with a vacuum source 13, and as a result the strip 10 is held against the
exterior surface 14 of the winding mandrel 12.
By means of a cutting arrangement 28, the banderole-shaped strip
10 is thereafter cut to a predetermined length, which in general has a maximum
length corresponding to the exterior periphery of the container to be banderoled.
In contrast to the arrangements of the prior art, no overlappi.ng
of the strip 10 is necessary, so that in an advantageous manner displacement of
the overlapping end pieces of the strip during the deep-drawing process can not
occur.
The arrangement of the invention also makes it possible in an advan-
tageous manner to work with shorter strip sec*ions the length of which may be
less than the exterior periphery of the container, for example when only portions
of the exterior periphery of the container are to be provided with a banderole-
shaped strip 10.
The glidably mounted slider 16 is thereafter moved into its second
operative position which is limited by means of the stop 20 against which with
the exterior surface 22. The further movement o:E the slider 16 is illustrated
by means of the arrow 36. During the further movement of the slider 16, the
rear end portion of the banderole-shaped strip 10 (which is still disposed
within the recess 17 of the slider 16) is moved by means of the slider 16 in a
6 -
s~'~
direction onto the exterior peripheral surface 34 of the winding mandrel 12 and
thereby arrives at the region of the opening 15. These openings 15, as is the
case with the opening 14, are in communication with a vacuum source 13
via the conduit 13'. When the opening 15 is placed in communication with the
vacuum source, the rear end piece of the banderole-shaped strip 10 which has
been moved by the s]ider 16, is held against the winding mandrel 12. In order
not to inter~ere with the forward end piece which is disposed in the region o~
the opening 1~ against the winding mandrel, the projection 16' has a recess
16" (see Figure 4).
In a first working skep the hollow mold 11, which is movable in the
axial direction moves relative to the stationary winding mandrel 12 so that the
openings 26 on the inner wall surface 25 of the hollow mold 11 are disposed at
the level of the banderole-shaped strips lO wound on the winding mandrel. The
openings 26 are in communication with the vacuum source during predetermined
periods of time. First of all~ the communication of the openings 1~, 15 with
the vacuum source 13 is interrupted, as a result of which the strip lO is re-
leased ~rom the exterior peripheral surface 34 of the winding mandrel 12 and,
due to the inherent elastic tension, bears against the inner wall surface 25 of
the hollow mold 11 in the region of the bores 26. Thereafter the openings 26
are placed in communication with the vacuum source, whereby the strip 10 is firm-
ly held against the inner wall of the hollow mold 11. In a further working step
the hollow mold ll then moves upwardly together with the thereto adhering strip
10 relative to the stationary winding mandrel 12 so that its upper base surface
24 forms the bottom o khe hollow mold 11. I`hereafter in a known manner, as has
been previously herein described, a container is formed by means of a deep-draw-
ing process with the aid of the hollow mold 11$ the con~ainer being made out of
a thermoplastic foil material. The banderole-shaped strip 10, which adheres
-- 7 --
5~j~
to ~he ex~erior wall of the container and annularly su-rrolmds it, is thus
permanently seale~ to the wall of such container.
ln the meantime the glidably mounted slider 16 has returned to its
first operative position so that with the introduction of a new banderole
section into the inlet opening of the recess 17 a new sequence of the afore-
described operative steps can be initiated.
For the further movement o:E the glidably mounted slider 16 into its
operative position in the direction of the arrow 36 there is provided a drive
mechanism 38. This drive mechanism is preferably a linear drive mechanism which
has a reciprocating piston acting in the operative directions which is actuated
by a pressure medium9 such as for example pressuriæed air.
With reference to Figures 6 and 7 there are illustrated advantageous
embodi.ments of the cut~ing arrangement 28 for precutting the banderole-shaped
s*rips 10 to a predetermined length. The embodiment of Figure 6 includes a
first stationary member 37 having a cutting edge 31 in which a further second
part 29 is rotatably mounted about an axis disposed in the plane of the strip
10, which part 29 has a centrally arranged guide slit 30 ~hich is adapted for
guiding the strip 10 therethrough. Upon rotational movement of the rotatable
part 39 the banderole-shaped strip 10 is cut at the cutting edge 31.
A particularly advantageous embodiment of a cutting arrangement 28 is
schematically illustrated in Figure 7. Such arrangement includes a knife 32,
which is arranged parallel to the outer surface of the slider and stationary
relative to its movement and thereby during the further movement of the slider
16 into its second operative position the banderole-shaped strips is cut in
the region of the funnel-shaped mouth of the recess 17. This embodiment dis-
tinguishes itself by having only a few parts which makes it particularly
reliable in operation.
-- 8 --
~3~
It is possible without any particular degree of difficulty, as is
schematically illustrated in Figure 8, to introduce banderole-shaped strips 10
into a plurality of hollow molds 11. In such arrangement for examp]e a row of
a plurality of hollow molds 11 are arranged side-by-side. For this purpose,
the slider 16 has a number of hollow molds 11 and a corresponding number of
recesses 17 and projections 16' through which the banderole-shaped strips are
guided.
