Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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COMPACT CUSHIONING CONVERSION
MACHINE AND METHOD USING PRE-FOLDED PAPER
FIELD OF THE INVENTION
The herein described invention relates generally to a cushioning
conversion machine and method for converting sheet-like stock material into a
cushioning product and, more particularly, to a way of supplying the stock
material to the conversion machine which enables the provision of a more
compact conversion machine.
BAC~KGF~OUND OF THE INVENTION
In the process of shipping an item from one location to another, a
protective packaging material is typically placed in the shipping case, or box, to
10 fill any voids and/or to cushion the item during the shipping process. Some
conventional protective packaging materials are plastic foam peanuts and
plastic bubble pack. While these conventional plastic materials seem to
adequately perform as cushioning products, they are not without
disadvantages. Perhaps the most serious drawback of plastic bubble wrap
and/or plastic foam peanuts is their effect on our environment. Quite simply,
these plastic packaging materials are not biodegradable and thus they cannot
avoid further multiplying our planet's already critical waste disposal problems.The non-biodegradability of these packaging materials has become increasingly
important in light of many industries adopting more progressive policies in
terms of environmental responsibility.
The foregoing and other disadvantages of conventional plastic packaging
materials have made paper protective packaging material a very popular
alterative. Paper is biodegradable, recyclable and composed of a renewable
resource, making it an environmentally responsible choice for conscientious
industries.
While paper in sheet form could possibly be used as a protective
packaging material, it is usually preferable to convert the sheets of paper into a
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relatively low density pad-like cushioning dunnage product. Cushioning
conversion machines in use today have included a forming device and a feeding
device which coordinate to convert a continuous web of sheet-like stock
material (either single-ply or multi-ply) into a three dimensional cushioning
product, or pad. The forming device is used to fold, or roll, the lateral edges of
the sheet-like stock material inward on itself to form a strip having a width
substantially less than the width of the stock material. The feeding device
advances the stock material through the forming device and it may also
function as a crumpling device and a connecting (or assembling~ device. The
10 cushioning conversion machine may also include a ply separating device for
separating the plies of the web before passing through the forrner, and usually
a cutting assembly for cutting the strip into sections of desired length.
In many packaging facilities the size of the cushioning conversion
machine is of minor importance. However, in other facilities space may be
15 quite limited and the size of the cushioning conversion machine is of
considerable importance. Also, a reduction in the size of a cushioning
conversion machine provides various advantages such as lower shipping costs,
easier delivery, more efficient service procedures, decreased need for storage
space, etc.
zo Successful attempts have been made over the years by Ranpak Corp. of
Painesville, Ohio, U.S.A., the assignee of the present application, to reduce the
size of cushioning conversion machines. For example, the cushioning
conversion machine marketed under the trademark PadPak'!9 (or PadPak Sr.~)
and disclosed in U.S. Patent No. 4,968,291 is approximately 42 inches high,
25 36 inches wide and 67 inches long, not including any stock roll mount. The
cushioning conversion machine sold under the trademark AutoPad'!9 and
disclosed in U.S. Patent No. 5,123,889 has a length of about 59 inches, a
width of about 34 inches and a height of about 12 inches, not including any
stock roll mount. Roughly, the AutoPad'~3 machine is no more than about one
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third the size of the PadPak~' machine while still producing a cushioning product
h of substantially identical properties. A further size reduction is exhibited by the
machine marketed under the trademark PadPak Jr.rM (or Junior~) and disclosed
in U.S. Patent Application No. 08/486,911, filed on June 7, 1995. The PadPak
Jr.~ machine is about 49 inches long, about 29 inches wide and about 12
inches high, not including any stock roll mount and operating handle.
In the foregoing and other types of conversion machines the forming
device, by the nature of its function, occupies a significant portion of the
overall volurne of the machine. The forming device has heretofore been
considered an essential component of the machine, notwithstanding continuing
efforts to provide compact conversion machines for applications where
machine size is important.
SUMMARY OF THE INVENTION
The present invention provides a novel cushioning conversion machine
and method for converting sheet-like stock material into a cushioning product
without the use of a conventional forming device, thereby enabling a
substantial reduction in the size of the machine. The machine and method are
characterized by the use of a web of flat-folded sheet-like stock material of one
or more plies and an expanding device which is operative to open up, or
"expandn, the flat-folded stock material before passage through a crumpling
andlor connecting device which also preferably functions to advance the stock
material through the machine. A preferred device for feeding, crumpling and
connecting ~assembling) the expanded stock material includes upstream and
downstream feed components which are driven at different speeds, the
upstream feed component being driven faster than the downstream feed
component to effect a crumpling action therebetween. The upstream feed
component preferably imparts to the expanded stock material an alternating
side-to-side pulling/pushing action while the downstream feed component
effects final assembly of the crumpled strip to provide a connected strip of
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cushioning product that may then be segmented into sections, as by cutting, to
form cushioning products of desired length.
The invention also provides a stock supply including at least one ply of
sheet-like stock material having portions thereof folded upon themselves along
the length of the stock material. The single-ply or multi-ply material preferably
is tri-folded with lateral edge portions thereof folded over on one another and
on a central portion.
The foregoing and other features of the invention are hereinafter fully
described and particularly poirlted out in the claims, the following descriptiono and annexed drawings setting forth in detail a certain illustrative embodirnent of
the invention, this embodiment being indicative, however, of but one of the
various ways in which the principles of the invention may be employed.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a schematic side view of a cushioning conversion machine
according to the invention with the side wall of the machine's housing nearest
the viewer partly broken away to permit viewing of internal machine
components, and with the machine situated on a table and being supplied with
pre-folded stock material from a floor supported stock supply.
Figure 2 is a schematic side view of a cushioning conversion machine
according to the invention, again with the side wall of the machine's housing
nearest the viewer partly broken away to permit viewing of internal machine
components and with the machine situated on a table, but with pre-folded
stock material being supplied from an eievated stock supply.
Figure 3 is a perspective view of a roll of flat-folded stock material for
use with the cushioning conversion machine.
Figure 4 is a perspective view of a fan-folded stack of flat-folded stock
material for use with the cushioning conversion machine.
Figure 5A is an end view of the flat-folded stock material of Figures 3
and 4, looking from the line 5A-5A thereof.
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Figure 5B is an end view of another version of the flat-folded stock
material.
Figure 5C is an end view of still another version of the flat-folded stock
material .
Figure 6 is an end view of an expanding device employed in the
cushioning conversion machine, the device being shown with the flat-folded
stock material of Figure 6A expanded thereby.
Figure 7 is a side view of the expanding device of Figure 6, without the
stock material.
Figure 8 is an end view of another version of expanding device, the
device being shown with the flat-folded stock material of Figure 5A expanded
thereby.
Figure 9 is a side view of the expanding device of Figure 8, without the
stock material.
Figure 10 is an end view of still another version of expanding device, the
device being shown with the flat-folded stock material of Figure 5A expanded
thereby.
Figure 1 1 is a side view of the expanding device of Figure 10, without
the stock material.
Figure 12 is an end view of a further version of expanding device, the
device being shown with the flat-folded stock material of Figure 5A expanded
thereby.
Figure 13 is a side view of the expanding device of Figure 12, without
the stock material.
Figure 14 is an end view of the cushioning conversion machine, showing
the expanding device of Figures 6 and 7 positioned relative to other
components of the machine.
Figure 15 is a sectional view of the machine taken along the line 15-15
of Figure 14, showing in particular the feed, crumpling and assembly device.
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Figure 16 is a top plan view of the cushioning conversion machine.
Figure 17 is an edge view of a lower support input wheel forming a part
of the feed, crumpling and assembly device.
Figure 18 is a side view of the lower support input wheel of Figure 17.
Figure 19 is an edge view of an upper feed input wheel forming a part of
the feed, crumpling and assembly device.
Figure 20 is a side view of the upper feed input wheel of Figure 19.
Figure 21 is an edge view of a lower support output wheel forming a
part of ~he feed, crumpling and assembly device.
Figure 22 is a side view of the lower support output wheel of Figure 21.
Figure 23 is an edge view of an upper compression output wheel forming
a part of the feed, crumpling and assembly device.
Figure 24 is a side view of the upper compression output wheel of Figure
23.
I:)ETAILED DESCRIPTION
Referring now in detail to Figures 1 and 2, an exemplary embodiment of
a cushioning conversion machine according to the invention is designated
generally by reference numeral 20. The illustrated machine 20 converts flat-
folded sheet-like stock material 22 into a three-dimensional cushioning product,20 or pad, 24.
The machine 20 includes a frame 25 to which are mounted a feeding,
crumpling and assembling device 26 and an expanding device 28. As
explained in greater detail below, the device 26 advances the flat-folded stock
material 22 through the expanding device 28 which causes adjacent portions of
25 the flat-folded stock material to be pulled apart or separated prior to passing
into the device 26 where it is crumpled and assembled into a connected strip,
i.e., the cushioning product 24. The machine also includes a device of any
desired construction for segmenting or dividing the connected strip into
sections of desired length, which device is, for example, the illustrated cutting
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assembly 34 (Figure 15). The machine preferably is provided with an outer
casing 35 which encloses the frame and other interior components of the
machine.
The roles the aforesaid conversion assemblies 26 and 28, and
components thereof, play in the formation of such a cushioning product are
explained below in detail. In regard to the various functions performed by the
noted assemblies and components thereof, the terms (including a reference to a
"means") used to identify the herein-described assemblies and devices are
intended to correspond, unless otherwise indicated, to any assembly/device
10 which performs the specified function of such an assembly/device that is
functionally equivalent even though not structurally equivalent to the disclosedstructure which performs the function in the illustrated exemplary embodiment
of the invention.
In accordance with a preferred embodiment of cushioning conversion
machine according to the invention, the major components of such conversion
machine are the feeding, crumpling and assembling device 26, the expanding
device 28, and the dividing device 34 (Figure 15). Noticeably absent in relationto the above mentioned prior art machines is a forming device which inwardly
rolls, or folds, the stock material into a narrower width three-dimensional strip
having a width approximating the width of the final cushioning product. The
elimination of a conventional former permits a great reduction in the size, and
particularly the length and width of the machine, as compared to conventional
machines. Specifically, the illusl-aLed preferred embodiment (excluding the
operating handle) is about 18 inches in length, about 18 inches in width and
about 12 inches in height for an overall volume reduction of about 85% when
compared to the above mentioned AutoPad~' machine that produces a pad of
approximately the same width and height.
In Figures 1 and 2, the machine 20 is shown supported on a table 36
and the stock material 22 is supplied from a stock roll 38 supported by a mount
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40. In Figure 1 the mount is positioned on the floor and the stock material is
fed upwardly to the machine, whereas in Figure 2 the mount is positioned on
top of the machine with the stock material being fed downwardly to the
machine. In either case and regardless of the angle at which the stock material
is fed from a supply thereof to the machine, a constant entry guide 42 at the
upstream end of the machine properly directs the stock material into the
expanding device 28.
As shown in Figures 1-3, the pre-folded, flat-folded stock material 22
may be supplied in roll form, i.e., as the stock ro!l 38. Alternatively, ~he stock
10 material may be supplied as a fan-folded stack 44 as shown in Figure 4. For adiscussion of the benefits obtained by using a fan-folded stack of stock
material, reference may be has to U.S. Patent No. 5,387,173. As shown in
Figure 4 the stack 44 may be contained in a carton 46 having an open top from
which the stock material is dispensed for passage through the conversion
machine.
Regardless of the mode of supply (roll, stack or otherwise), the stock
material 22 consists of a web of flat-folded sheet-like stock material of one ormore plies having portions thereof folded upon themselves along the length of
the stock material. Preferably, the stock material 22 comprises at least two
and preferably two or three superimposed plies each preferably 27-30 inches
wide prior to being folded. A preferred stock material consists of a
biodegradable, recyclable and reusable material such as paper and more
particularly 30-50 pound basis weight Kraft paper.
In one form of flat-folded stock material 22 shown in cross-section in
Figure 5A, the single-ply or multi-ply material is tri-folded with opposite lateral
edge portions 50 and 51 thereof folded over on one another and on a central
portion 52. The lateral edge and central portions may be of approximately
equal width for use in a conversion machine according to the invention.
However, the width of the lateral edge portions may be varied. In Figure 5B
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another form of stock material 22' has lateral edge portions 50' and 51' that
are about equal width but less than the width of the central portion 52'. Also,
as illustrated in Figure 5C, the edge portions 50" and 51" may be folded over
opposite sides of the central portion 52" to give the web 22" of stock material
a Z-shape.
In each one of these embodiments, the lateral edge and central portions
of the stock material ply or plies form a plurality of layers joined at a
longitudinally extending fold to at least one other layer. In the folded condition
of the stock nnaterial, the la~ers of the stock rnaterial lay flat one atop the
10 other. However, upon separation of the layers from adjacent layers, generallyV-shape or U-shape channels are formed with folds disposed at or near the
boKoms of the channels.
In Figures 6 and 7, details of the expanding device 28 are shown. The
expanding device includes a mounting rnember 60 to which a separating
t5 member 62 is joined. The mounting member 60 includes a transverse support
or mounting arm 64 having an outwardly turned end portion 66 and an
oppositely turned end portion 68 to which the separating member 62 is
aKached. The outer end portion 66 is mounted to the machine's frame 25
(Figure 1) by a bracket 70 and suitable fastening elements 72. The mounting
member may be formed from bar or tube stock, and the cantilevered central
portion 73 thereof may be sloped relative to a transverse center plane of the
path of the stock material through the machine as best illustrated Figure 14.
The separating member 62 includes a transverse support 74 and fold
expansion elements 76 at opposite ends of the transverse support that are
25 relatively thicker than the transverse support, with respect to the narrow
dimension of the stock material. In the illustrated expanding device, the
~ mounting member 60 is formed by a rod or tube, and the fold expansion
elements are formed by rollers supported for rotation on the transverse support
at opposite ends thereof. The transverse support 74 is aKached near one end
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thereof to the adjacent end portion 68 of mounting member 64 for support in
cantilevered fashion.
As shown in Figures 14 and 15, the mounting member 64 positions the
separating member 62 in alignment with a guide chute 80 that has a funnel or
converging mouth inlet 82. The guide chute 80 is substantialiy rectangular in
cross-section. It further will be appreciated that the separating member has a
width approximating the width of the cushioning product 24, which width
corresponds closely to the width of the guide chute 80, and the rollers 76 have
a diameter or height approximating the thickness of the cushioning product
10 which closely corresponds to the height of the guide chute 80. Also, in
relation to the flat-folded stock material 22 of Figure 5A, the width of the
central portion 52 of the stock material is substantially equal to the width of
the separating member (from outer sides of the rollers), such that the folds (orcreases) F are proximate the laterally outer corners of the rollers opposite the mounting member, as is preferred.
The expanding device 28 is designed for use with the flat-folded stock
material shown in Figures 5A or 5B. In Figure 6, the stock material 22 of
Figure 5A is shown in expanded condition. During the conversion process, the
layers of the stock material (formed by the edge and central portions of the plyor plies) travel through the expanding device 28. More particularly, the central~ portion 52 travels over the sides of the rollers 76 opposite the mounting arm
64, while the inner edge portion 51 travels in the narrow V-shape or U-shape
slot formed between the transverse support 74 and the mounting arm 64 and
the other or outer edge portion 50 travels over the side of the mounting arm 64
furthest the separating member 62. As a result, the edge portions are
separated from one another and from the central portion, thereby introducing
loft into the then expanded material which now takes on a three dimensional
shape as it enters the guide chute 80 (Figure 14) of the feeding, crumpling and
connecting device 26.
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In Figures 8 and 9, another version of expanding device is shown at 28'.
As shown, the separating member 62' includes a pair of centrally joined
transverse support elements 74' to which respective pairs of fold expanding
rollers 76' are mounted at the ends of the support elements for rotation. The
rollers at each end of the separating member cooperate to expand the adjacent
fold F of the stock material. An advantage of two rollers is that they can rotate
in opposite directions for more smooth passage of the stock material thereover.
In Figures 10 and 1 1, still another version of expanding device is shown
at 28". In this versisn, the laterally spaced apart fold expanding elements 76"
10 are in the form of expansion blocks over which the stock material passes. Theexpansion blocks preferably are wedge shape with the narrow end 88 thereof
disposed upstream of the wider end 90. This provides for a progressive guided
opening of the stock material folds.
Figures 12 and 13 show at 92 another version of expanding device for
use with the flat-folded stock material 22" of Figure 5C. In this version, fold
expansion elements 94 and 95 are rolalably supported at the ends of
respective transverse support elements 96 and 97 which are attached at the
opposite ends thereof in cantilevered fashion to respective mounting posts 98
and 99. The mounting posts are mounted to a bracket 100 for securement to
the frame of the machine. As shown, the support eie",ei1ls are cantilvered in
opposite transverse directions. Accordingly, the central portion 52" of the
stock material travels through a slot formed between the support elements 96
and 97 whereas the lateral edge portions 50" and 51" travel on opposite outer
sides of the support elements as shown in Figure 12. The expansion elements
may be in the form of rollers as shown, but any of the aforesaid expansion
elements may be used as desired.
- Referring now to Figures 14-16, wherein further details of the cushioning
conversion machine are shown, the frame 25 can be seen to include side plates
1 10 and 112 which are joined together by transverse frame members. The
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feeding, crumpling and assembling device 26 includes a first or input pair of
wheels, i.e., an upper feed wheel 118 and a lower support wheel 120. The
feed wheel 118 is fixed to a shaft 119 that is rotatably supported by and
between the side plates 110 and 112. The lower support wheel 120 is
supported for rotation on an axle shaft 121 which has opposite ends thereof
attached to respective floating supports 122 in the form of bars.
The feeding, crumpling and assembling device 26 further comprises a
second or output pair of wheels, i.e., an upper compression wheel 123 and a
lower support wheel 124. The compression wheel is fixed to a shaft 125 that
10 is rotatably supported by and between the frame side plates 110 and 112 and
rotatably driven by a motor 126, such as an electric motor. The support wheel
124 is supported for rotation on a shaft 127 which has opposite ends thereof
attached to respective floating bars 122 downstream of the shaft 121.
As shown, the wheels 118 and 123 extend into the interior of the guide
chute 80 through a slot in the top wall of the chute, whereas the wheels 120
and 124 extend through a slot in the bottom wall of the chute. As seen in
Figure 16, the slots are located centrally between the side walls of the guide
chute for engaging the central longitudinal region of the expanded folded strip
passing though the guide chute.
Each floating bar 122 has attached thereto a pair of guide pins 128
which are guided by holes in a respective guide plate 132 attached to the side
plates. The guide plates may function as convenient mounts for the guide
chute 80 which is attached thereto by suitable brackets or other means.
The guide pins 128 extend substantially perpendicular to the movement
25 path of the stock material between the feed and support wheels 118 and 120
(perpendicular to the wide dimension of the guide chute 80) and have thereon
respective springs 136 which resiliently bias the floating bar and thus the
support wheel 120 towards the feed wheel 118. As shown, the springs are
interposed between the guide plate and stops 138 on the rernote ends of the
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guide pins. The guide pins preferably extend through oversized guide holes in
the respective guide plate to permit tilting movement of the floating bars with
respect to the frame about a transversely extending axis while the longitudinal
position of the floating bars is maintained by the ends of the shaft 127 being
guided in elongated slots 142 in the side plates 110 and 112, which slots
extend substantially perpendicular to the movement path of the stock material
between the feed and support wheels. Thus, while tilting movement is
permitted, the axes of the compression wheel 123 and corresponding support
whee! 124 will be held in alignment relative to the nnovernent path of the strip10 of material passing therebetween. When material is not being fed through the
machine, the springs 136 will resiliently hold the wheels of each pair against
one another, or with a small gap therebetween by reason of the floating bars
engaging the guide plates.
In the illustrated embodiment, the two shafts 119 and 125 are driven
15 positively by the motor 126, the shaft 125 through a drive chain 148 and the
shaft 119 through a drive chain 150 trained around sprockets respectively
secured to the shafts 119 and 125. The sprockets are selected such that the
shaft 119 will rotate faster than the shaft 125 at a desired speed ratio. Of
course, it will be appreciated that other drive mechanisms may be employed if
desired, such as gear trains.
As further shown in Figures 19 and 20, the feed wheel 118 is generally
cylindrical in shape, with a middle portion 156 in the form of an annular groovewhich, for example, may have an approximately semi-circular cross section or a
rectangular cross-section. The feed wheel also has opposite axial end portions
158 and 159, each of which has a cylindrical periphery interrupted at regular
intervals by flat faces 160. The flat faces 160 of the axial end portion 158 areopposite arcuate areas 162 of the axial end portion 159, while inversely the flat
faces of the axial end portion 159 are opposite arcuate areas of the axial end
portion 158. The arcuate areas are preferably knurled or otherwise provided
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with friction-enhancing means for relatively slip free engagement with the stockmaterial.
As further shown in Figures 17 and 18, the support wheel 120, which
coacts with the feed wheel 118, has a generally cylindrical shape at axial end
5 portions 164 thereof which are disposed on opposite sides of a middle section
165 where there is provided a radially outwardly protruding annular rib 166
which is rounded. The cylindrical end portions 164 preferably are knurled or
otherwise provided with friction-enhancing means for relatively slip free
engagement with the stock materi21.
The expanded stock material leaving the expanding device, and
consisting of one or more paper plies folded onto themselves, passes between
the wheels 118 and 120, and is fed forwardly by the feed wheel 118. The
expanded folded strip or band of material will be pinched along the central
region thereof with a variable force, as explained further below, by the support5 wheel 120, when passing between the arcuate areas 162 of axial end portions
158 and 159 and the cylindrical axial end portions of the wheel 120. The
central region of the expanded folded strip, however, will be relatively free
when passing between the flat faces 160 and the cylindrical axial end portions
164 of the support wheel 120. Because of the offset between the flat faces of
20 the axial end portions 158 and 159, the strip will therefore be fed alternately
from each side of its longitudinal axis, instead of being pulled only axially. This
advance by successive pulls from one side an then the other back and forth
makes it possible to have at the center a surplus of paper with respect to its
flat configuration, this surplus being generated by the rib 166 fitting in the
25 groove 156, which provides crumpling.
As further shown in Figures 23 and 24, the compression wheel 123 iS
generally cylindrical in shape and has two end portions 170 having knurled or
ribbed cylindrical surfaces separated by a radially relieved middle portion 172
which may have a smooth outer diameter surface. The ribbing on the end
14
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portions forms circumferentially spaced apart teeth that preferably are flat at
~ their radially outer ends. The support wheel 124, further shown in Figures 21
and 22, is a cylinder which may have a smooth outer diameter surface or one
provided with knurling or other friction-enhancing means on which the ribbing
will roll, the strip of material coming from the first pair of wheels and being
pinched between the teeth or ribbing 173 of the compression wheel and the
outer diameter surface of the support wheel, with a variable force, as explainedfurther below.
The force exerted by the sprin3s 136 may be distributed in such a way
that the pressure exerted by the wheel 120 is greater than that exerted by the
wheel 124. This difference in forces is justified by the fact that the wheel 120works with the feed wheel 118, and must therefore pinch the material
proportionally more than the wheel 124, which only serves as support for the
assembly teeth on axial end portions 170. The ratio of forces may be from 1/3
to 2/3, but this can be different if desired by changing the springs with springs
having different spring constants or by changing the position of the stops on
the guide pins, for example.
As above mentioned, the motor 126, driving the wheel 123, also drives
the wheel 118 in the same direction but at a higher speed. The result is that
the strip of material leaving the pair of wheels 118 and 120 is going to be
retarded by the pair of wheels 123 and 124 rotating at a slower speed. As a
result, the material will be compressed between the two pairs of wheels,
constantly creating a series of transverse folds. Crumpling of the material
results from this difference in speed of rotation of the two pairs of wheels, the
upstream pair turning faster than the downstream pair. The speed ratio may be
on the order of about 1.7:1 to about 1.9:1. Of course, the speed ratio could
- be different, according to circumstances, for example the degree of crumpling
desired. In the same way, the aforesaid ratio may be valid for wheels 118 and
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123 of the same diameter, but it could be different for wheels of different
diameters.
For further information regarding a feeding, crumpling and connecting
assembly similar to that just described, reference may be had to European
Patent Application No. 94440027.4, filed April 22, 1994 and published on
November 2, 1995 under Publication No. 0 679 504 A1, which is hereby
incorporated herein by reference.
The conversion machine also preferably comprises the strip dividing
ass2mbly 34 that divides or separates the connected strip exiting from between
10 the downstream pair of wheels into sections of desired length. In the
illustrated embodiment the separating assembly is in the form of a cutting
assembly that cuts the thus produced continuous strip at a desired length to
form a cushioning product of desired length. In this manner, the length of the
cushioning product may be varied depending on the intended application. The
particular construction and operation of the strip-cutting assembly is not
essential to the present invention. However, reference may be had to U.S.
Patent Application No. 08/386,355 for a cutting assembly similar to that
illustrated, or to U.S. Patent Application No. 08/110,349 and 08/478,256 for
other types of cutting assemblies. Reference may also be had to U.S. Patent
20 Application No. 08/486,911 for details of a single handle operator for operating
the cutting assembly and also for controlling the motor. The handle operator is
shown at 172 in Figures 14 and 15. These patent applications are hereby
incorporated herein by reference for their showings of cutting and handle
operator assemblies.
The cushioning product produced by the machine is essentially the same
as that produced by a machine like that shown in the above mentioned
European Patent Application No. 94440027.4.
Although the invention has been shown and described with respect to
certain preferred embodiments, it is obvious that equivalent alterations and
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modifications will occur to others skilled in the art upon the reading and
understanding of this specification. The present invention includes all such
equivalent alterations and modifications.
17
