U.S. patent number 3,572,689 [Application Number 04/744,009] was granted by the patent office on 1971-03-30 for method and apparatus for folding articles.
This patent grant is currently assigned to International Paper Company. Invention is credited to Philip G. Day, Warren R. Furbeck, Charles A. Lee, James A. Murphy.
United States Patent |
3,572,689 |
Murphy , et al. |
March 30, 1971 |
**Please see images for:
( Certificate of Correction ) ** |
METHOD AND APPARATUS FOR FOLDING ARTICLES
Abstract
A series of flat articles are advanced along a path at regular
intervals and are folded by continuously traveling fingers which
engage an article intermediate its ends and fold the same. The
fingers advance the articles to a station at which the folded
articles are deposited as the fingers automatically withdraw from
the folds. The folded articles may be abutted seriatim into a stack
within an accumulator in the form of a conveyor traveling a speed
considerably slower than the speed of the traveling fingers.
Inventors: |
Murphy; James A.
(Toronto,Ontario, CA), Lee; Charles A. (Knoxville,
TN), Furbeck; Warren R. (Knoxville, TN), Day; Philip
G. (Cooksville,Ontario, CA) |
Assignee: |
International Paper Company
(New York, NY)
|
Family
ID: |
24991072 |
Appl.
No.: |
04/744,009 |
Filed: |
July 11, 1968 |
Current U.S.
Class: |
493/423; 493/422;
493/938 |
Current CPC
Class: |
D06F
89/00 (20130101); B65H 45/12 (20130101); Y10S
493/938 (20130101) |
Current International
Class: |
D06F
89/00 (20060101); B65H 45/12 (20060101); B65h
045/16 () |
Field of
Search: |
;270/61,80--85,78,70,62,63 ;93/1 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Charles; Lawrence
Claims
We claim:
1. In an apparatus for folding flexible articles, an endless
conveyor for advancing a series of said articles resting thereon
and having their centers spaced apart a predetermined distance
along a first predetermined path to one end of said conveyor where
said conveyor is inverted, guide means at said one end of said
conveyor to constrain the leading end of each article to follow a
curved path to the exit of said guide means, said leading end of
said article being free to depend downwardly from the exit of said
guide means, finger means including at least one finger to engage
the depending article substantially medially and hold it against
the inverted conveyor to travel with the conveyor along a second
predetermined path, means to form a fold at the location of said
finger, takeup means to receive said folded articles, and means for
retracting said fingers from said folds of the articles upon their
delivery to said takeup means.
2. An apparatus in accordance with claim 1 in which said takeup
means is a takeup conveyor for carrying said articles at a first
speed, and in which an accumulating conveyor following said
receiving conveyor is aligned with the path of travel of said
articles while on said take up conveyor, said accumulating conveyor
traveling at a speed sufficiently slower than the speed of said
takeup conveyor so incoming folded articles are abutted with
preceding articles in the accumulating conveyor whereby the
articles are abutted and form a stack.
3. An apparatus in accordance with claim 1 in which said finger
means includes a pair of endless bands each carrying a plurality of
fingers about an endless path, each of said fingers on one band
being aligned with a finger on the opposite band for simultaneously
engaging and advancing a respective article, and said means for
retracting includes guides for directing said bands in paths
diverging from each other to withdraw the fingers automatically
from the folded article and thereby deposit the article in said
takeup means.
4. An apparatus in accordance with claim 1 in which said fingers
travel on a substantially horizontal plane when folding the article
and in which the means for folding the article directs said end
portions into a substantially horizontal plane when forming said
fold and in which said article is free to pivot downwardly about a
finger to dispose the folded article substantially vertically
before it is deposited in said takeup means.
5. An apparatus in accordance with claim 2 in which said takeup and
accumulating conveyors include means to engage the sides of the
folded articles and hold them upright as they are conveyed by said
conveyors.
6. An apparatus in accordance with claim 5 in which each of said
side engaging means includes opposed endless bands for engaging the
opposite sides of the upright articles and in which said conveyors
have a bottom conveyor belt for supporting and conveying the lower
ends of the articles.
7. In an apparatus for folding articles such as a disposable
diaper, an endless conveyor conveying diapers to one end thereof,
means defining a curved chute adjacent said conveyor end to guide
the leading end of each diaper to travel in an arcuate path around
said conveyor end, means including endless bands each carrying a
series of spaced fold fingers along predetermined paths to engage a
diaper substantially centrally thereof as the diaper exits from
said curved chute and to advance the diaper in the direction of
finger travel, forming means disposed along said path of finger
travel to force the extremities of said diaper together and thereby
form a fold at said finger, said diapers being thereafter free to
pivot about said finger to orient said legs of said diaper
downwardly, means for automatically withdrawing said finger from
said fold, and conveyor means operable when said finger withdraws
to hold said folded diaper upright and convey it away.
8. The method of folding and stacking a series of flexible articles
comprising the steps of advancing said unfolded articles
successively along a predetermined path at regular intervals,
engaging each article substantially centrally by at least one
finger while leaving the ends thereof free, forcing the free ends
of said article together to form a fold in said article at said
finger, withdrawing said finger to release said article therefrom,
and abutting successive folded articles and holding the sides
thereof with the articles being disposed in an upright position and
in a column to form a stack of folded articles.
9. A method in accordance with claim 8 in which each of said folded
articles are abutted in a stack by conveying said folded articles
at a given speed into an accumulator traveling at a speed which is
substantially slower than said given speed so that each of the
articles incoming to the accumulator abuts a preceding article.
10. A method in accordance with claim 8 in which flat unfolded
articles are moved in a first direction to the exit end of a
conveyor and are constrained to travel in an arcuate path about the
exit end of the conveyor, whereupon the leading portion of the
article is released for engagement of a succeeding portion by said
finger.
11. The method of folding and stacking a series of flexible flat
articles comprising the steps of advancing the unfolded articles at
a first predetermined speed successively along a first
predetermined path at regular intervals to a first station, at said
first station engaging a predetermined portion of each of said
articles successively with at least one finger while leaving the
ends thereof free, by said finger advancing each article along a
second predetermined path at said predetermined speed past a second
station to a third station, at said second station folding the
articles about the respective fingers, disposing the respective
folded articles vertically dependent from said fingers between said
second and third stations, at said third station engaging the edges
of the folded articles, thereupon withdrawing the fingers from the
respective articles, carrying the engaged folded articles at the
same predetermined speed to a fourth station, and at said fourth
station abutting successive folded articles in a stack.
12. In an apparatus for folding articles, means for advancing said
articles in succession at regular intervals along a first
predetermined path, finger means including fingers moving along an
endless second predetermined path to catch a predetermined portion
of each of said articles successively and advance the articles
along at least a portion of said second predetermined path, a
former disposed along said second predetermined path for folding
said article at said finger, a takeup conveyor disposed along said
second predetermined path for receiving said folded articles and
moving them in a third predetermined path, and means for retracting
said fingers from said articles after their delivery to said takeup
conveyor, said finger means including a pair of endless bands each
carrying a plurality of fingers, each finger on one band being
aligned with a finger on the other band to engage the article
substantially simultaneously with its aligned finger, and said
means for retracting including means for carrying said bands with
said fingers thereon along diverging paths so that the finers
automatically withdraw to release the folded article.
13. In an apparatus for folding articles, means for advancing said
articles in succession at regular intervals along a first
predetermined path, finger means including fingers moving along an
endless second predetermined path to catch a predetermined portion
of each of said articles successively and advance the articles
along at least a portion of said second predetermined path, a
former disposed along said second predetermined path for folding
said article at said finger, a takeup conveyor disposed along said
second predetermined path for receiving said folded articles and
moving them in a third predetermined path, and means for retracting
said fingers from said articles after their delivery to said takeup
conveyor, said takeup conveyor including means for engaging
opposite sides of the folded articles and holding them upright.
Description
This invention relates to an apparatus for and a method of folding
articles and also to collecting folded articles seriatim into a row
or stack of abutted articles.
The present invention is particularly useful for folding relatively
flat, flexible articles such as sheets, laminae or the like. The
illustrated embodiment is described in connection with, but is not
limited to, the folding and stacking of disposable diapers which
basically include an absorbent pad of cellulosic material with an
envelope thereabout comprised of a facing sheet for disposing
against a child's skin and an outer backing sheet. The diapers are
relatively flexible and limp and the envelope may be damaged by
scuffing, tearing or soiling. The preferred embodiment of the
invention may be used to fold a steady stream of diapers issuing
from a production line at relatively high rates such as, for
example, 150 diapers per minute.
To fold continuous streams of articles at such relatively high
rates in a neat and orderly manner, has heretofore required
relatively expensive, complex equipment employing elaborate
electrical or vacuum control systems to fold, transport, orient and
stack the diapers. With the present invention, a continuous stream
of diapers are folded, transported and oriented into abutted rows
or stacks with a relatively simple mechanical apparatus.
Accordingly, an object of the invention is to provide an improved
apparatus for and method of folding articles, such as diapers.
A more specific object of the invention is to provide a simple
mechanical arrangement in which traveling pins fold, transport and
position diapers for collection into rows or stacks of abutted
articles.
Other objects and advantages of the invention will become apparent
from the following detailed description taken in connection with
the accompanying drawings in which:
FIG. 1 is a side elevational view of an apparatus for folding
diapers and collecting them in a stack or row;
FIG. 2 illustrates a single diaper prior to folding;
FIG. 3 shows a collection of folded diapers disposed in a row;
FIG. 4 is a horizontal plan view of the apparatus shown in FIG. 1,
taken substantially along the line 4-4 of FIG. 1;
FIG. 5 is a horizontal sectional view taken substantially along the
line 5-5 of FIG. 1, showing a portion of the drive for the
apparatus of FIG. 1;
FIG. 6 is an enlarged vertical sectional view of a portion of the
apparatus shown in FIG. 1, taken substantially along the line 6-6
of FIG. 1;
FIG. 7 is an enlarged vertical sectional view taken along the line
7-7 of FIG. 1, showing the side conveying belts of the apparatus
shown in FIG. 1;
FIG. 8 is an enlarged fragmentary view of a portion of the
apparatus shown in FIG. 1 taken substantially along the line 8-8 of
FIG. 1;
FIG. 9 is an enlarged detailed view of a folding finger and its
support as used in the apparatus shown in FIG. 1;
FIG. 10 is an enlarged, vertical sectional view taken along the
line 10-10 of FIG. 1 showing a portion of the drive for the fold
fingers shown in FIG. 9;
FIG. 11 is an enlarged, vertical cross-sectional view taken along
the line 11-11 of FIG. 1 showing a drive for side conveyor belts of
the apparatus shown in FIG. 1;
FIG. 12 is an enlarged, vertical sectional view of a portion of the
apparatus shown in FIG. 1 taken along the line 12-12 of FIG. 1;
FIG. 13 is an enlarged, vertical sectional view taken along the
line 13-13 of FIG. 1 showing a central gearbox and drives therefrom
for the apparatus shown in FIG. 1;
FIG. 14 is an enlarged, vertical cross section taken substantially
along the line 14-14 of FIG. 1 and showing a drive for an
accumulating conveyor for the apparatus shown in FIG. 1;
FIG. 15 is a vertical, sectional view taken substantially along the
line 15-15 of FIG. 1 showing a discharge conveyor for the apparatus
shown in FIG. 1; and
FIG. 16 is the diagrammatic view showing in phantom lines a
sequential folding, transporting and positioning of a diaper by the
apparatus of FIG. 1.
As shown in the drawings for purposes of illustration, the
invention is embodied in a method of and apparatus for, very
generally, folding a continuously moving stream of articles, such
as a disposable diaper 17 (FIG. 2) issuing continuously from a
diaper-making machine (not shown) and for collecting the diapers
into a row or stack 19, as best shown in FIG. 3, of folded diapers.
Partly for historical reasons, the term "stack" will be used herein
to refer to this collection of folded diapers arranged with their
flat sides abutting in a relatively neat array, irrespective of the
fact that in the preferred embodiment of the invention the diaper
collection extends horizontally rather than vertically as was
generally the case with stackers of the prior art.
As will be explained, the present invention is adapted to operate
continuously and at a relatively high rate of speed, for example,
150 diapers per minute or in excess thereof and to fold the diapers
neatly and evenly so that the stack of diapers is aligned in a neat
array for a subsequent packaging operation. The diapers may range
in length from approximately 14 to 18 inches and in width from
about 9 to 12 inches, but the invention is not limited either to
diapers or to diapers of these sizes. The diapers are folded midway
between embossed areas at the ends 21 of the diapers at the
location of tacking embosses 23 (FIG. 2) which tack the innermost
portion of folded pleats 25 along the sides of the diaper. The
illustrated diaper is formed generally within a creped tissue cover
or envelope with an internal absorbent pad of wood pulp (not
shown). The present invention has the capability of folding such a
diaper without tearing or soiling the creped tissue cover and
folding the diaper evenly so that the resulting legs 27 (FIG. 3)
have their ends 21 evenly depending from a center fold line 29.
Preferably, the diapers are stacked with the vertical sides 28 of
the legs 27 aligned for facilitating a subsequent packaging of a
group of diapers.
As an aid to understanding the invention, the preferred method of
folding and stacking the diapers 17 will be described first. In the
diaper-making machine (not shown), the diapers are formed in a
continuous strip which is severed to form individual diapers at a
high rate of speed, e.g., 150 or more diapers per minute. These
issue from the diaper-making machine for folding according to the
present invention. As the diapers leave the diaper-making machine,
they are transferred directly to an input carrier 31 (FIG. 1) which
is in the form of an endless conveyor or belt 33 movable along an
upper run to convey the diapers, which are disposed longitudinally
at regular predetermined intervals and are in a flat unfolded
condition, from right to left as viewed in FIGS. 1 and 16. The belt
33 is driven in timed relationship to the diaper machine so that
the diapers traveling leftward along this first predetermined path
arrive at regular intervals at the left end of the input conveyor
and are guided by a curved chute 35 which constrains the flat
diapers to follow a curved path.
As the diaper leaves the curved chute, as best seen in FIG. 16, at
least one folding pin or finger 37 catches or engages the diaper at
a predetermined portion, preferably at the center, at what will be
the fold line 29, and moves with the diaper while holding it
against the lower run of the conveyor belt 33 traveling rightward
along this second predetermined path. The folding finger 37 and the
belt 33 move at the same velocity, holding the diaper against
slipping and shifting. If the diaper were allowed to slip on the
fold finger 27, one leg would become misaligned from the end of the
other leg or one leg of the diaper would become longer than the
other leg of the diaper. The finger 37 and belt 33 carry the diaper
forward (to the right in FIG. 16) to and through a former 39 which
includes a plate 41 for compressing the diaper legs 27 together and
forming a definite fold line 29 at the location of the fold finger
37. As the diaper exits from the former 39, the diaper legs 27
swing down as the diaper pivots about its fold 29 and fold finger
37. The now vertically disposed folded diaper moves into a
receiving means in the form of a takeoff conveyor 43 which includes
a pair of side belts 45 (FIG. 4) which engage the opposite vertical
sides 28 of the diaper legs while a bottom conveyor belt 49
disposed on a belt support 48 (FIG. 10) engages the ends 21 of the
diapers to move the diapers along a third predetermined path. The
takeoff conveyor 43 and each fold finger 37 travel at substantially
the same speed, and the takeoff conveyor 43 supports the diapers as
the fold finger 37 automatically withdraws from the fold 29. The
now folded diaper is carried forward to an accumulator 51 which
causes the spaced diapers 17 to abut and form the stack 19.
In the preferred embodiment of the invention, the accumulator 51 is
generally similar to the takeoff conveyor 43 in that it has a pair
of side belts 53 for engaging the sides 28 of the diaper and a
bottom belt 55 for engaging the ends 21 of the diapers. These
accumulator belts travel at a speed significantly slower than the
takeoff conveyor speed so that the folded diapers which are spaced
from one another, as best seen in FIG. 3, in the takeoff conveyor
abut at flat faces 47 and form a stack in the accumulator. Thus,
flat, unfolded diapers disposed end to end are folded and stacked
in a continuous row.
Proceeding now with a detailed description of the preferred
embodiment of the apparatus for carrying out the invention, the
input conveyor belt 33 is shown being moved along a downward
incline from right to left in FIGS. 1 and 16 toward an idler roll
59 about which the belt reverses its direction of movement and
travels rightwardly to an opposite drive roll (not shown). The
diapers on the belt 33 have been deposited thereon from a
diaper-making machine wherein the diapers 17 are formed in a
continuous strip and then cut into individual diapers delivered end
on to the belt 33. The belt 33 may be driven at a speed which is
slightly faster than the speed of travel in the diaper-making
machine with the result that the ends 21 of successive diapers 17
become spaced a predetermined distance.
Along the upper run, the belt 33 is disposed on the upper surface
of an inverted support channel 65 (FIGS. 6 and 7) which is fastened
along its downturned edges to a pair of parallel plates 67. The
plates 67 are secured to and supported by angle shaped brackets 69
(FIG. 7) bolted to vertical columns 71 which are in the form of
angle members fastened at lower ends (FIG. 1) to a main support
base 73 extending beneath the entire apparatus. As best seen in
FIG. 1, the channel 65 is inclined downwardly from right to left
and carries bearings 74 at its left end to journal the idler roller
59 for rotation about a substantially horizontal axis. It will be
appreciated that the opposite end of the conveyor belt 33 is
supported by a channel similar to the channel 65 and is wrapped
about a drive roller (not shown).
A diaper moving to the left end of the conveyor belt 33 at the
roller 59 moves into an inlet end of the curved chute 35 defined
between the arcuately curved belt and a curved plate 72 which is
spaced from the belt by a distance greater than the thickness of a
diaper. The curved plate 72 is bent on an arc concentric with the
adjacent arcuate curve of the belt 33 and terminates at a lower end
defining an outlet for the curved chute 35. The diapers travel
through the chute 35 at the speed of the belt 33 without slipping
relative to the belt.
At what is defined as a first station, the diaper is released at
the outlet end of the chute 35 so that the leading end of the
diaper falls free, moving rightward and downward under the effects
of inertia and gravity. As the center of the diaper emerges from
the chute 35, it is caught by at least one fold finger 37 and held
against the belt 33, the finger and belt thereafter moving together
at the same velocity from this first station. This provides the
necessary gripping force for holding the diaper 17 at the fold 29
and prevents the slipping of one of the diaper legs 27 relative to
the other diaper leg. The fold finger 37 forces the diaper against
the conveyor belt 33 as it is guided along its return run by a dead
plate 75 (FIGS. 1, 6 and 16) which extends from adjacent the idler
roller 59 to an idler roller 77, as best seen in FIG. 1. The dead
plate 75 is supported by suitable studs 79 (FIG. 6) extending
upward to an overhead plate 81 which spans horizontally across the
brackets 83 fastened at their lower ends to main frame legs 87
fastened to the frame base 73. The dead plate 75 guides the belt 33
for substantially horizontal movement to adjacent the idler roller
77 from which the belt 33 moves upward and rightward to another
idler roller 89 (FIG. 1) journaled in the support frame plates 67,
and the belt 33 is suitably supported until it reaches the driving
roll (not shown) at the right end of the input conveyor 31.
At a second or folding station, the finger 37 pulls the diaper
rightward through the former 39 to fold the diaper intermediate its
ends. The former 39 includes, in this instance, the left end of the
belt 33 and the dead plate 75, which functions as the upper portion
of the former 39, and the forming plate 41 (FIG. 16), which
functions as the lower portion of the former 39. The diaper legs 27
are compressed between the lower forming plate 41 and the belt 33
at the left end of the dead plate 75. The forming plate 41 is
spaced from the belt 33 and dead plate 75 at a predetermined
distance by a pair of spaced bars 95 which are fastened to the
brackets 83 (FIG. 1) so that the diaper legs 27 are pressed
together with a compressing force as the diaper is pulled through
the narrow slot between the belt 33 and the forming plate 41. As
best seen in FIGS. 1 and 16, a downwardly curved arcuate bend 93 is
formed on the left end of the forming plate 41 to provide a smooth
guiding and supporting surface for camming the diaper legs together
and into a position for easy entry into the entrance of the former
39.
In the present instance, the diapers 17 are folded, conveyed
forwardly and oriented in proper position by the fold fingers 37 as
the fingers are carried by an endless band such as a chain 99 along
a portion of an orbital path. At a third or transfer station, the
fold fingers 37 are automatically retracted from the fold 29 of the
diaper. In the apparatus as shown in the drawings, the retraction
is achieved by means which move the fingers outward from the path
which the diapers 17 are constrained to follow, the diapers being
directed along a centerline 101 (FIGS. 4 and 5) through the takeoff
conveyor 43 to the accumulator 51.
As best seen in FIGS. 4 and 5, it is preferred that there be two
sets of folding fingers 37 on respective chains 99 disposed on
opposite sides of the centerline 101 with a finger in each set
matched with and extending into alignment with a finger of the
other set with which it cooperates during engagement with the
diaper. The inner free ends 102 of the fingers 37 are quite close
together when they first engage a diaper and move through the
former 39, but the free ends 102 continually and gradually move
apart as they convey the diapers into position between the side
belts 45 (FIG. 4) of the takeoff conveyor 43, at which point the
fingers 37 retract fully from the diaper. After withdrawal from a
diaper, the fingers continue to move to the right (FIGS. 4 and 5)
to a pair of sprockets 103 which define the end of the forward
travel for the chains 99. At the sprockets 103, the chains 99
travel downward, as best seen in FIG. 1, to a lower sprocket 105
and then return to the left, as seen in FIG. 1, to another lower
sprocket 107 at which the chains travel upward to an overhead
sprocket 109 to begin their forward rightward run.
In the preferred embodiment of the invention, the fold fingers 37
are rigid, cylindrical rods or pins which have their free ends 102
projecting from a bracket 107 attaching their other ends to
respective chain links (FIG. 9). Each fold finger 37 has a
cylindrical collar 109 secured to it, and the collar is adapted to
ride along an upper guide rail 111 (FIGS. 6 and 9) which is
supported by upstanding brackets 113 bolted to the upper flange of
the channel frames 85. These channel frames 85 are supported on the
frame legs 71 and 87 and diverge from the centerline 101
therebetween. The chains 99 are guided along their rightwardly
extending, diverging paths by guide bars 115 which are inserted
between the side plates of the chain to engage the conventional
rollers on the chains 99. These guide bars 115 are fastened to the
outer sides of the brackets 113, as best seen in FIG. 6. The weight
of the transported diaper tends to pivot the inner free ends 102 of
the fold fingers downwardly about the respective chains 99. To
limit this pivoting, the other ends of the fold pins abut and ride
along the underside of guide bars 90 which extend parallel to and
along the upper runs of the chains 99. The bars 90 are suitably
fastened by brackets to the channel frames 85. Along the lower and
return run, the chains 99 and the collars 109 for the fold fingers
37 slide along lower guide rails 119 (FIG. 6) supported by angles
121 fastened to the respective frame legs 71 and 87.
With the present invention, the diapers 17 are folded as they move
along in a continuous stream without the use of complicated sensing
mechanisms and control systems for timing the various operations.
The timing of the various mechanisms is obtained by timing the
travel speed of the various conveyors to the fold fingers 37. For
instance, the fold finger chains 99 are driven at a speed
corresponding to that of the conveyor belt 33 by the lower right
sprockets 105 (FIGS. 1 and 10) which are journaled in bearing in
bearing mounts 123 carried by brackets 125 which (as best seen in
FIG. 10) are fastened to the lower flanges of the channel frames
85. A drive sprocket 127 has a hub suitably fastened to the hub of
sprocket 105 at locations internally of the bearing mounts 123 so
that the sprockets 105 and 127 turn together. Wrapped about the
sprockets 127 are driving chains 129 extending downwardly to
sprockets 131 fixed to a drive shaft 133 journaled in bearings 135
disposed in mounting blocks 136 fixed to the main frame base 73.
The drive shaft 133 is disposed for rotation about a generally
horizontal axis and receives a driving torque at its right end (as
seen in FIG. 10) from a chain 137 carried by a sprocket 139 fixed
to the drive shaft 133. As best seen in FIGS. 1 and 5, this chain
137 is tensioned by an idler 140 and extends rightwardly and
upwardly to a sprocket 141 fixed to an output shaft 143. The shaft
143 is driven through a gearbox 145 by a line timing shaft 147
extending rightwardly to the diaper-making machine. The line timing
shaft 147 provides the power and the timing for driving each of the
various drives for the apparatus as will be described. Thus, it
will be seen that through this chain and sprocket drive, the
folding fingers 37 are driven in timed relationship to the
diaper-making machine which is delivering the diapers to the inlet
side of the input conveyor 33 so that the folding fingers 37 remain
in a predetermined and timed relationship to meet the midpoint of
the diapers 17 as they emerge from the curved chute 35.
As the fold fingers 37 withdraw from the diapers 17, as best seen
in FIG. 4, the side belts 45 of the takeoff conveyor 43 engage the
vertical sides 28 of the diaper legs and center the diapers on the
centerline 101 of the takeoff conveyor. To this end, the side belts
45 are guided by converging ends 149 of a pair of dead plates 151
spaced on opposite sides of the centerline 101 to form a mouth at
the inlet end of the takeoff conveyor 43. The dead plates are
disposed vertically and beneath the plane of travel of the fold
fingers, and the dead plates are generally parallel from the
converging inlet ends 149 to adjacent the discharge end of the
takeoff conveyor. The dead plates 151 are supported by horizontally
extending studs 153 which extend to and are bolted to brackets 155
(FIG. 10) upstanding from and fastened to the upper flange of the
channel frames 85. Adjacent the inlet ends 149, the side belts 45
are wrapped about an idler pulley 156 mounted on a vertically
disposed shaft 158 which is journaled in a bearing mount 160 (FIG.
7) on the upper flange of channels 85.
To drive the side belts 45 at the proper speed, they are wrapped
about knurled drive rolls 157 fastened to upstanding drive shafts
159 (FIG. 11) to rotate about the vertically disposed axes of these
shafts. From the drive rolls 157, the belts are wrapped about
tension rollers 161 which are journaled on upstanding posts 163
fastened at their lower ends in crank arms 165. These crank arms
are mounted on a horizontal support 167 spanning and fastened to a
pair of frame legs 87. The crank arms 165 are pivoted to and
secured in positions to assure that the side belts 45 have the
proper tension. The drive shafts 159 are journaled in upper
bearings 169 on the horizontal support and in lower bearings 171 on
the base plate 73. Intermediate these bearings, a pulley 173 is
fixed to each drive shaft 159 and these pulleys are driven by a
drive belt 175 (FIGS. 5 and 11) which is tensioned by an idler
pulley 177 on a shaft supported by a crank arm 179. The belt 175 is
driven by an output sheave 181 of a right angle, gear drive unit
183 which in turn is provided with an input sheave 185 driven by a
belt 187 extending forwardly to a sheave 189 fixed on a jack shaft
191 (FIG. 5). The jack shaft 191 is disposed generally horizontally
and adjacent the frame base 73 and, as best seen in FIG. 13,
carries an attached sheave 193 about which is trained a belt 195
extending upwardly to a pulley 197 fixed to an output shaft 199 of
the main gearbox 145 which is driven by the line timing shaft 147.
In this manner, the side belts 45 may be driven at the same speed
of travel as the fold finger chains 99.
The takeoff conveyor 43 also includes the bottom belt 49, which
engages and supports the ends 21 of the diaper legs 27, and extends
generally horizontally from the former 39 to adjacent the
accumulator 51. At its left end, the bottom belt 49 is wrapped
about an idler roll 201 supported on a shaft 203 (FIG. 4) journaled
in bearings 205 which are slideably adjustable upon turning screws
207. The bearings 205 and the adjustment screws 207 for the idler
roll 201 are mounted in brackets 209 (FIG. 1) fastened to the
channel frames 85. During movement along its upper run, the bottom
belt 49 is supported by a dead plate 211 (FIG. 7) which is fixed to
a horizontal cross brace 213 extending between the webs of the
channel frames 85.
To drive the bottom belt 49 at the same speed as the side belts 45
and the fold fingers 37, the bottom belt is, at its forward
discharging end, wrapped about a driving roll 215 (FIG. 11) fixed
to a horizontal shaft 216 rotatably mounted in bearings 217 in turn
mounted on bearing mounts 219 on the horizontal support 167. One of
the ends of the shaft 216 extends outwardly and carries a sheave
221 about which is trained a belt 223 extending to a sheave 225
(FIGS. 5 and 10) fastened to the jack shaft 133, previously
described as being suitably connected to the line shaft 147 and
driving the folding finger chains 99. Thus, the jack shaft through
the drive described will cause the bottom belt 49 to be driven in
timed relationship to the travel speed for the fold fingers 37 and
the side belts 45.
During transfer of the folded diapers 17 from the takeoff carrier
43 to the accumulator 51, the diapers are guided by a pair of
stationary, bridging guides 227 (FIGS. 4 and 12) which engage the
vertical sides 28 of the diaper legs 27 which are being conveyed
rightward by the bottom belt 55 of the accumulator 51. Herein, the
bridging guides 227 are in the form of vertical plates which are
disposed between the takeoff conveyor side belts 45 and the
accumulator side belts 53. More specifically, the bridging guides
are secured in adjusted positions by horizontally disposed studs
229 (FIG. 12) which extend to an upstanding leg of an angle shaped
bracket 231 fixed to the horizontal support 167.
To assure that the diapers 17 are continuously driven forwardly as
they transfer between the takeoff conveyor 43 and the accumulator
51, the bottom belt 55 of the accumulator has its input end
projecting leftwardly into the discharge ends of the side belts 45
of the takeoff conveyor, as best seen in FIGS. 1 and 4. At this
end, the bottom belt 55 is wrapped about a horizontally disposed
roll 233 (FIG. 12) which is fastened to a support shaft 235
journaled in suitable bearings in bearing mounts 237 fastened to
the horizontal support 167. The bottom belt 55 is supported for
generally horizontal movement by a dead plate 139 (FIG. 13)
fastened to the inwardly directed flanges of angle shaped plates
241 which are fastened by suitable brackets to the supporting frame
for the folding apparatus.
As can best be seen in FIGS. 1 and 4, the bottom belt 55 carries
the diapers rightwardly to the accumulator side belts 53 and then
into a pair of stationary side guides 243 (FIG. 15) from which the
now stacked diapers can be removed in predetermined quantities, for
example, in groups of 12. The stationary side guides 243 are
disposed to guide the vertical sides 28 of the folded diapers 17
and are fastened by suitable brackets 245 bolted to the horizontal
portion of an inverted U-frame 247, as best seen in FIG. 15, which
is supported by suitable brackets on the frame of the
folder-stacker apparatus.
The diapers are collected and abutted at a fourth or accumulating
station within the belts 53 and 55 which are driven at a speed
which is considerably slower than the speed of the belts 45 and 49
of the takeoff conveyor 43. Thus, the spaced, faster moving diapers
will abut one another in the accumulator 51. The accumulator bottom
belt 55 is driven during its return run by reversing the belt 55
about a first idler 249 (FIG. 1) and then forming a loop about a
driving roll 251 (FIG. 1) before continuing to the left on the
return run to the idler roll 233 at its input end. The driving roll
251 (FIG. 15) is fixed to a shaft 253 extending between and
journaled in bearings on supporting plates 255 of the frame 247. On
an end of the shaft 253 is fixed a sheave 257 driven by a belt 259
which extends downwardly to a sheave 261 (FIGS. 1 and 5) on a jack
shaft 263 journaled in a bearing mounted in a bracket 265 fastened
to the frame base 73 (FIG. 5). The jack shaft 263 is disposed
generally horizontally and carries at one end a sheave 267 driven
by a belt 269 which extends leftwardly, as viewed in FIGS. 1 and 5,
to a sheave 271 of a gear reducer unit 273 which is driven by the
jack shaft 191 which has been previously described as a portion of
the drive for the side belts 45 of the takeoff conveyor 43. The
gear reducer unit 273 causes considerable reduction in the speed of
the accumulator belt 55 relative to the takeoff conveyor belts
whereby the diapers become abutted within the accumulator 51 with
their faces 47 disposed together as seen in FIG. 16.
The accumulator side belts 53 engage the vertical sides 28 of the
folded diapers and hold them as they accumulate in a stack which
continuously moves rightward. These side belts 53, as viewed in
FIG. 4, are guided by dead plates 275 (FIGS. 4 and 13) extending
between and closely adjacent to vertically disposed rolls 277 and
279. The dead plates 275 are supported by horizontally extending
studs 281 (FIG. 13) fastened at an adjusted position to vertically
disposed legs of the angle plates 241. The side belts 53 move
rightward from the vertically disposed idler rolls 277 journaled on
upstanding shafts 283 (FIG. 1 & 12) fastened to the horizontal
support 167. To tension the belts 53, the idler rolls 285 (FIG. 14)
are journaled on upstanding posts 287 fixed at lower ends to crank
arms 289 adjustably mounted on a horizontal plate 291 spanning a
pair of vertical frame legs 87.
As best seen in FIG. 14, the drive rolls 279 are knurled to provide
the driving friction necessary to drive the side belts 53 wrapped
about them. Supporting shafts 293 for the knurled drive rolls are
disposed vertically and are rotatably supported in upper bearings
295 on the horizontal plate 291 and in lower bearings 297 fastened
to the base plate 73. Driving sheaves 299 are fastened to the
support shafts 293 and a driving belt 301, as best seen in FIGS. 5
and 14, extends from these sheaves 299 about an idler pulley 303
mounted on a post 305 carried by a crank 307 to keep the driving
belt 301 tight. The driving belt 301 is driven by a sheave 309
(FIG. 5) which is driven through a right angle geared unit 311
(FIGS. 5 and 14) which, in turn, is driven by the jack shaft 263
which has been previously described as driving the accumulator
bottom belt 55. In this manner, both the side belts 53 and the
bottom belt 55 may be driven at the same slower speed relative to
the takeoff conveyor belts to make sure that the diapers accumulate
prior to moving rightward into the discharge guide plates 243 from
which they are removed either automatically or manually in groups
having a predetermined number of diapers therein.
To facilitate an understanding of the operation of the apparatus
and the method of folding the diapers, a brief description of the
apparatus will now be given. The incoming diapers 17 are disposed
flat in an endwise succession one behind the other and spaced from
each other on the upper surface of the conveyor belt 33. They are
moved, as viewed in FIGS. 1 and 16, to the left end of the conveyor
31 at the roll 59 at which the belt 33 reverses its direction of
movement. At the left end of the conveyor 31, the leading edge of
the diaper abuts and is guided downward by the curved plate 72 as
it moves with the belt 33 in an arcuate path about the roll 59 and
at belt speed. When the leading diaper end reaches the bottom edge
of the curved plate 72, inertia and gravity carry the leading edge
downward and rightward to strike a downwardly extending curved
plate 312.
As the midpoint of the diaper leaves the curved chute 35, opposed
folding fingers 37 carried by chains 99 abut the diaper at the
location of the tack embosses 23 and hold the diaper at this
midpoint against the belt 33 as it moves rightward along its lower
horizontal run. The fingers 37 move through but a short distance
before they move into a slot defined between the overhead belt 33
and the forming plate 41. The curved portion 93 of the forming
plate 41 guides the diaper legs 27 as they trail the fingers 37
upward into the slot. The diaper thereby becomes folded and the
legs 27 are compressed against each other. The compression is
sufficient to form a definite fold 29 between the legs at the
fingers 37. When the fingers 37 withdraw the diaper legs 27
completely from the former 39, the diaper legs pivot under the
action of gravity downward about the fingers 37 until the bottom
edges 21 engage the upper surface of the bottom belt 49 of the
takeoff conveyor 43. The outer ends of the fold fingers are held by
the bars 90 from pivoting about the connections to the chains 99
and, as the diaper travels rightward, the fold fingers gradually
retract from the fold. The diaper is now folded and vertically
disposed with the fold 29 on top as it moves into the converging
mouth being defined by the side belts 45 which center the diaper on
the centerline 101 between them. As the side belts engage the
diaper sides 28, the fingers 37 withdraw from the fold 29. The
diaper is then wholly supported vertically, along its sides by the
side belts 45 and at its ends 21 by the bottom belt 49. The fold
fingers 37 continue to travel to the right to sprockets 103 and
then begin their return movement.
While within the takeoff conveyor 43, the folded diapers 17 are
spaced from one another by the distance between diaper centers on
the belt 33. Just prior to leaving the takeoff conveyor side belts
45, the ends 21 of the diapers move into engagement with the bottom
belt 55 of the accumulator 51 which gives them a continued forward
impetus through very short, bridging guides 227 to the accumulator
side belts 53 which are generally aligned with the side belts 45
for the takeoff conveyor 43. During the transfer of a diaper to the
accumulating conveyor, the side edges of the diaper are briefly
engaged by the side belts 45 which are traveling at higher speed
than the bottom belt engaging the lower ends of the diaper.
However, the side edges of the diaper are soon being retarded by
the stationary guides 227 while the bottom belt is still moving
forwardly. This transfer occurs relatively quickly and over a small
space. Also, the inertia of the diaper precludes instantaneous
changes of speed with the result that the diaper transfers quite
readily into the accumulating conveyor while still retaining its
vertical disposition.
In the accumulator 51, the diapers 17 are engaged on the vertical
sides 28 and on the lower ends 21 by belts which are moving at the
same speed to the right as viewed in these FIGS., but much slower
than the belts of the takeoff conveyor 43. The accumulator side
belts 53 and bottom belt 55 are driven at a predetermined, but
sufficiently slow speed that each incoming diaper abuts its
preceding diaper and travels rightward a distance about equal to
its thickness before being abutted by a following diaper. As the
speeds of the conveyors can be readily adjusted, a desired ratio
between their speeds can be maintained so that diapers accumulate
relatively uniformly as diagrammatically illustrated in FIG. 16.
The diapers are carried forwardly in a row or stack from the
accumulator 51 into a discharge section defined by the pair of
stationary side plates 243 which guide the edges of the diaper
(FIGS. 1 and 15) as the bottom belt 55 for the accumulator
continues to move rightward. A predetermined number of diapers,
usually 12, may then be removed manually or automatically by
machinery for subsequent compression and packaging operations.
In the event of jamming of diapers 17 somewhere in the
folder-stacker apparatus, there may be provided an automatically
operated bypass mechanism which will allow incoming diapers to
bypass the folder-stacker apparatus. For this purpose, the line
shaft 147 may be provided with an overload torque sensor 330 (FIG.
15) which will sense an overload torque condition on the line shaft
147. Such overloads may be caused by a jamming of diapers somewhere
within the apparatus. The overload torque sensor 330 operates an
electrical switch which in turn operates a fluid cylinder 331 (FIG.
1) fastened to a bracket 333 on the side frame 65 to retract an
operating piston and rod 335 which is connected at its free end to
a crank arm 337. The crank arm is pivoted on a shaft 339 which
pivotally mounts the curved plate 72. The operation of the cylinder
331 causes the crank arm 337 to pivot the shaft 339 and curved
plate 72 which moves to an inoperative position such as shown in
dotted lines in FIG. 16. In this retracted position the curved
plate is high above the belt 33 and is no longer effective to cause
the diaper to follow the belt 33 about the roll 59. Another takeoff
conveyor 341 (FIG. 16) may be disposed adjacent the curved guide
chute 35 so that when the guide plate 72 is in its retracted
position, the incoming diapers 17 may continue to feed leftward
onto the conveyor 341. At the same time, the signal from the
overload sensor may be used to shut down the folder-stacker
apparatus to permit repair of the difficulty.
It will be seen from the foregoing that the folding and stacking
apparatus is capable of operating at relatively high speed and of
accurately folding flexible articles such as diapers in a
continuous and automatic manner. The apparatus has been found to
fold with relative ease articles which could be easily torn. The
apparatus may be operated for relatively long periods of time with
little or no maintenance.
While a preferred embodiment has been shown and described, it will
be understood that there is no intent to limit the invention by
such disclosure but, rather, it is intended to cover all
modifications and alternate constructions falling within the spirit
and scope of the invention as defined in the appended claims.
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