CA2105769C

CA2105769C - Folder construction

Info

Publication number: CA2105769C
Application number: CA002105769A
Authority: CA
Inventors: Kasimir Kober
Original assignee: Chicago Dryer Co
Current assignee: Chicago Dryer Co
Priority date: 1991-03-27
Filing date: 1992-03-19
Publication date: 1995-03-21
Anticipated expiration: 2012-03-19
Also published as: US5435802A; WO1992017633A1; AU1758892A; US5300007A

Abstract

A folder (10) for towels (1) and similarly-sized laundry pieces is provided which is adapted to form a variety of folds in a rapid manner whereby high production is assured. The provided folder (10) employs an air pervious surface (40) assuring a con-trolled, rolling folding of the article side panels (R, L) over an article central panel (C) without any air entrapment, thereby assur-ing precise folds, and attractive folded articles.

Description

210~7~9 FOLDER CO~Sl~UCTION

~L
Field Of The Invention This invention relates to a ~mall piece folder and more partieularly pQrtains to ~ folder adapted to form French folds in small articlQs ~uch a~ towQls, hospital gowns and the like. The provid~d apparatus i8 adapted to preeisely form a variety of fold~ by 8imple apparatus settings in a rapid manner.

8ackground Of The Invention The prior art include~ many mae~ ~ adapted to form cross folds and French fold~ in small laundry flatwork items such as towel~.
SjoL~Lom U.S. Patent No. 2,754,113 diseloses an apparatus for longit~ n~lly folding and ~ ^ folding sheet material~ ineluding towels by means of air blasts and fold-forming plates after the article b~ing folded has - eome to a ~top and is clamped in fixed position.
S~ostrom U.S. Patent No. 2,545,798 diseloses the sequential forming of longi~ l parallel folds in sheet material by moving side plates on whieh portions of the sheet material rest over a eentral plate beneath which a portion of the sheet material lies. Neither of the S~ostrom patents suggest~ the ~G.~LollQd manner of instan~n~us fold formation provided by the apparatus of the invention as will be herein~ftQr Ae~ibQd in detail.
T~graf et al. U.S. Patent No. 4,060,227 is ~~ direeted to a folder for folding small flat pieces by forming a French fold and a eross fold in eontinuously moving small pieces such as towels by means of air bars ~ 210~769 ~

and width control blades. The Landgraf et al. apparatus is limited to the folding of small pieces only. The pieces being folded are continuously moving with uncontrolled panel folding. This patent represents the nearest prior art of which applicant is aware to the invention hereinafter disclosed.
Kober U.S. Patent No. 4,093,205 is directed to a laundry folder employing opposed adjustable cam plates for forming a French fold on a moving towel. Also disclosed is an air-discharging bar for forming a cross fold while a towel or the like is traversing a plurality of conveyors while moving through a folder to a stacker. The folder of this patent is incapable of forming the variety of folds formed by the folder of this application and does not suggest the controlled panel folding of this invention.
The folder of this invention is designed to eliminate the major shortcomings of the prior art by pro-viding a versatile folder capable of folding towels of varied sizes in a rapid and efficient manner. The provided apparatus is adapted to form French folds by substantially instantaneously folding opposed side panels of sheet material over a central panel in precise, overlying longitudinal alignment. The prior art does not suggest the instantaneous controlled folding hereinafter described in detail.
It is thus an object of this invention to provide a substantially instantaneous manner of forming French folds in laundry pieces such as towels, napkins and small sheets in the course of which air is progressively rolled out or squeezed from between the lateral and central panels assuring desired and precise panel edge alignment.
It is another object of this invention to provide a folding apparatus adapted to automatically form any of a plurality of desired folds in a towel or the like being processed by means of simple control actuation.

~ 210~769 It is still another object of this invention to provide a folder which is readily adaptable to the processing and formation of desired folds in a variety of towels of varying sizes.
S It is a further object of this invention to provide a folder which although rapid and flexible in operation is both rugged and compact occupying a minimum of valuable floor space.
The above and other objects of this invention will become more apparent from the following description when read in the light of the accompanying drawings and appended claims.
Summary Of The Invention According to one aspect of the present invention there is provided a folding apparatus comprising conveyor means for moving a foldable article along a path of movement; air discharge means disposed adjacent the conveyor means for laterally discharging air to substantially instantaneously ~old a panel of a foldable article on the conveyor means; the panel extending from a hinge axis to a distal end and being urged by the air discharge means into overlying relation with a connected portion of such foldable article to which it is joined along such hinge axis; fold control means for controlling the folding of such panel relative to the article connected portion and -3a-comprising a barrier disposed over the conveyor means in adjacent relationship therewith whereby laterally discharged air from the air discharge means urges a proximal portion of the panel extending from the hinge axis, downwardly against the conveyor means, and simultaneously upwardly urges a trailing portion of the panel into slidable engagement with the barrier which limits the upward movement of such panel relative to the conveyor means; the discharged air forming a laterally moving concavity in a panel portion interconnecting the panel proximal and trailing portions; the interval between the conveyor means and the barrier being substantially uniform to enable such cavity-forming air to laterally move the panel in a substantially uniform manner as the proximal panel portion rolls over the article connected portion until the panel distal portion disengages from the barrier and is driven onto the surface of the underlying connected portion of the foldable article.
According to another aspect of the present invention there is provided foldable apparatus for folding articles comprising a first conveyor means; edge-defining means disposed adjacent the first conveyor means; the first conveyor means being adapted to move a first portion of a foldable article disposed thereon beneath the edge-defining means; second conveyor means for conveying a lateral ycc/J~

r~4 ~ 2105769 -3b-portion of a foldable article at an elevation above a foldable article first portion disposed on the first conveyor means; air discharge means disposed adjacent the second conveyor means for substantially instantaneously folding a lateral foldable article portion over the edge-defining means; such lateral portion extending from a proximal end where connected to the foldable article first portion to a lateral portion distal end; and means for controlling the movement of lateral foldable article portions over the edge-defining means; the movement controlling means being disposed relative to the second conveyor means whereby a lateral foldable article portion on the second conveyor means is folded over the edge-defining means by the air discharge means and urged into slidable engagement with the movement controlling means as the proximal end of such lateral portion disposed adjacent the edge-defining means is urged downwardly into surface-to-surface contact with upper surface portions of the edge-defining means; the air discharge means and the movement controlling means effecting a substantially instantaneous rolling, folding action of a foldable article lateral portion, progressing continuously in a substantially uniform manner from the lateral portion proximal end where engaging the edge-defining means to such lateral portion distal end.

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-3c-According to another object of the present invention there is provided folding apparatus comprising conveyor means for moving a foldable article along a path of movement; spaced edge-defining means disposed adjacent the conveyor means; air discharge means associated with each of the edge-defining means for discharging air to substantially instantaneously fold lateral portions of such foldable article about the edge-defining means; means for controlling the discharge of air in sequence through the air discharge means; barrier means for controlling the folding of each lateral portion of such foldable article and located adjacent the foldable article path of movement and the edge-defining means; the air discharge means urging lateral portions of such foldable article over the edge-defining means, into slidable engagement with the fold controlling means as air is progressively exhausted from beneath each lateral portion from the edge-defining means about which folded to a lateral portion distal end; the foldable article lateral portions being rolled into engagement with underlying support surfaces provided by the edge-defining means and such foldable article in surface-to-surface relationship while slidably engaging the fold controlling means; underlying conveyor means disposed beneath the first conveyor means and moving in a direction generally opposed to that of the direction of movement of B

-3d-the first conveyor means; the first and underlying conveyor means comprising continuous ribbons moving about opposed rolls;
superposed rolls of the first and underlying conveyor means disposed at the end of the first conveyor means defining counter-rotating pinch rolls; second air discharge means oppositely disposed to the counter-rotating pinch rolls for urging a desired transverse portion of a foldable article dropping from the end of the first conveyor means into the bite of the counter-rotating pinch rolls; means for measuring the length of a foldable article while moving on the first conveyor means operatively connected to the second air discharge means;
means for sensing the leading edge of a foldable article upon moving from the first conveyor means, and means for activating the second air discharge means responsive to the measuring means and sensing means.
According to another object of the present invention there is provided folding apparatus comprising means for moving a foldable article along a path of movement; air discharge means disposed adjacent the path of movement for substantially instantaneously folding a lateral panel portion of such foldable article extending from a hinge axis to a distal end of such panel portion about the hinge axis into overlying relationship with a connected portion of the foldable article;
the air ~ B

-3e- 2105769 discharge means being disposed above the path of movement of such foldable article connected portion; edge-defining means for forming such hinge axis disposed adjacent such foldable article path of movement; the means for moving a foldable article comprising a first conveyor portion for moving a first foldable article portion along a first plane and a second conveyor portion for moving a panel portion of such foldable article connected to the first foldable article portion in a second plane disposed above the first plane; the edge-defining means being disposed between the first and second planes; means disposed adjacent the path of movement of such foldable article for controlling the folding of such panel portion relative to such article connected portion when folded by the air discharge means about the edge-defining means; the fold controlling means being so disposed relative to the path of movement of such foldable article whereby such foldable article panel portion slidably engages the fold controlling means when urged by the air discharge means into overlying relationship with a connected portion of the foldable article and air is substantially instantaneously exhausted from beneath the panel portion of such foldable article from the hinge axis to the panel portion distal end and such panel portion is rolled over such underlying connected portion of such foldable article with an air induced ycc / ~) ~
A

~ 2105769 downward bias from the hinge axis to the panel portion distal end.
According to another object of the present invention there is provided folding apparatus comprising conveyor means for moving a foldable article along a path of movement and comprising a first conveyor portion for moving a foldable article first portion in a first plane, and a second conveyor portion for moving a second foldable article portion connected with such first foldable article portion in a second plane; edge-defining means for forming a hinge axis between foldable article portions and disposed in a plane between the planes of the conveyor means first and second portions adjacent such article path of movement;
air discharge means disposed between the first and second planes adjacent each edge-defining means for substantially instantaneously folding a second foldable article portion on the second conveyor portion about the edge-defining means and over a first foldable article portion on the first conveyor portion; means disposed adjacent the first conveyor portion for controlling the folding by the air discharge means of a foldable article second portion relative to a foldable article first portion; the air discharge means urging distal portions of such foldable article second portion into slidable engagement with the fold controlling means when urged into overlying ycc/J~

.~

~-` 21057~9 -3g-relationship with a foldable article first portion as proximal portions of the foldable article second portion disposed at such edge-defining means are downwardly urged and simultaneously rolled over such underlying first portion of such foldable article from the hinge axis between the foldable article first and second portions, to a distal end of such foldable article second portion.
In one embodiment of the provided invention a towel feed conveyor of continuous ribbons is provided which conveys a towel or the like beneath spaced parallel runners with opposed lateral towel side panels being carried by conveying ribbons which slidably engage opposed supporting side plates. If the towel has less than a m~x;mum length, air bars sequentially fold the towel side panels over the runners as the towel is moving and conveyed to the end of an upper feed conveyor. The air discharges instantaneously urge each towel side panel in sequence against an air permeable grid disposed over the towel and feed conveyor as each panel is moved over the towel central panel. The air blasts progressively squeeze air from between the side and central panels from the panel hinge connections with the towel central panel to the distal terminal ends of the side panels. The French folded towel may be subsequently cross folded in the course of being urged onto an underlying conveyor and onto the trap doors of a towel stack former as will hereinafter be described in detail.

ycc/J ~

A

~092/17633 - =

If the towel being processed is beyond a maximum size which prevents the completion of the sequential panel folding as the towel moves on the upper feed conveyor, the feed conveyor is momentarily stopped to enable the folding steps to be completed prior to the discharge of the folded towel from the end of such conveyor.
In the cour~e of travel of the piece being folded through the apparatus the same i~ constantly monitored as to location and size thereby enabling the desired folds to be made therein w~th precision, and assuring a trouble-free folder operation.

~escription Of The Drawin~s Figures 1, 2 and 3 are schematic per3pective views illustrating various folds which may be made utilizing the folder of this invention;
FIG. 4 is a perspective view of the conveyors and certain aqsociated auxiliary apparatus elements employed in the folder construction of this invention;
~ IG. 5 is a schematic side elevational view of one embodiment of a folder ~ade in accordance with this invention;
FIG. 6 is a perspective view of a folder made in accordance with this invention partially broken away and illustrating a trap door of a stacker shown in association with conveyors adapted to move ~tacka of folded articles to l:he feed end of the folder;
FIG. 7 is a fragmentary perspective view of the feed end of a folder made pursuant to this invention illustrating adjustable fold-forming runners and associated ~eA~s for forming the interval therebetween;

21~169 ~ , , .
FIG. 8 is a side pQrspeetivQ view illustrating the motor and associated means for ad~usting the interval between the fold-forming runn~rs and movable ribbon-~u~ort plates of a folder made pursuant to this invention;
FIG. 9 is a fragmentary psrspeetivQ view illustrating an air bar elamp whieh may be ~mployed in the folder of this invention;
FIGS. 10-14 are ~eetional ViQW~ illustrating step-wise the novel folding aetions ~ffeeted in air-inltiated folds earried out in a folder of the provided invention. The illustrated fold-forming runners are shown in position for the proeessing of wide towels or the like in th0se figures;
FIG. 15 is a perspeetiva view of a height-adjusting assembly whieh may be employed in regulating the height of the air pervious barr~ er employed in a folder of this invention:
FIG. 16 is a fragmentary perspeetivQ view illustrating a portion of a trap door employed in the sta~tn~ dQvice of th~ folder of th~s invention;
FIG. 17 iB a fragmsntary end elevational view partly in seetion, illustrat$ng a trap door arrangement employed in the folder of thi~ invention, and illustrated in overlying relationship with a eonveyor for removing stacks of folded artiele~;
FIG. 18 is a ~ehematie perspeetive view illustrating drive motors and ~ employed in the folder of this invention;
FIG. 19 is a sehematie per~pective view illustrating a modified half-fold which may be formed in a towel or the like, employing the folder of this invention;
-PCT/uSs2/02223 21~769 FIG. 20 is a functional block diagram generallyschematic illustrating the electrical relationship of apparatus elements in the provided folder, and FIG. 21 is a sectional view similar to FIG. 10 illustrating fold-forming runners in adjacent relation for the forming of folds on towel~ or the like of narrow width.

De~cri~tion Of The Preferred Embodiment The folder of this invention is adapted to form a plurality of attractive folds in laundry flatwork such as towels, napkins and the like. More particularly, the folder of this invention is adapted to fold towels up to 72 inches in length preciRely in three parts wherein the opposed lateral panels are folded in overlapping relationship with a center panel to define what is known in the laundry trade as a "French fold". Such folded to~el may be then draped over a towel bar or the like presenting an attractive appearance.
Figures 5 and 6 illustrate a towel folder 10 made in accordance with this invention, and comprising opposed side frames 12 in which are journaled rotatable roll~ ~ome of which rotatably drive continuous belt~ or ribbon~ defining overlying conveyors which move a towel, a small sheet or the like through the folder 10. Each frame half 12 may be mounted on casters 15 for ready relocation of the folder when desired. Figure 5 illustrates an upper feed conveyor 14 comprising an initial upwardly inclined portion 16 which is inteqral with main horizontal conveyor portion 18. The upper conveyor 14 possesses large central ribbon 20 more clearly seen in FIG. 4, and ribbons 21, 23 and 25 movable therewith and disposed to either side of ribbon 20. Ribbon 20 has approximately the width of the panels of a towel after the same i~ French folded.

~92117633 2 1 0 5 7 6 9 PCI/US92/02223 t , ~

Ribbons 20, 21, 23 and 25 move about rolls 22 of the upper conveyor 14 and ribbons 24 of underlying conveyor 26 move to the left in an opposite direction to the ribbons of conveyor 14 as illustrated in FIGS. 4 and 5.
It will be more clearly noted from FIGS. 4, 5 and 10-14 that a foldable towel with its leading end centered on inclined portion 16 of upper conveyor 14 prior to moving onto the horizontal upper conveyor portion 18 for purposes of having a French fold formed therein, will be driven by central ribbon 20 moving over a support surface 19 a~ shown in Figs. 10-14 as it passes beneath overlying, elonqate runners 28 (see FIG. 7). The runners are laterally adjustable and in parallel relation for purposes of forming parallel fold or hinge lines in the course of folding a towel. O},~os~d panel portions R and L
of the towel T are conveyed by the ribbon~ 21, Z3 and 25 simultaneously with movement of the towel center panel on ribbon 20, as clearly seen in Figures 10-14. It will be noted from FIG. 7 that the leading edges of runners 28 are upwardly turned to facilitate movement of a towel therebeneath. The towel ~ide portion~ R and L are elevated relative to the towel center panel C moving beneath runners 28 while supported on wide ribbon 20 as towel panel portions R and L are conveyed by the opposed sets of ribbons 21, 23 and 25 which are slidably driven over fixed, underlying support plates 32 (see Figures 7 and 10-14). The plates 32 may be supported at longitudinal intervals by brackets 27 secured to inner walls of the side frames as illustrated, Air bars 30 are supported by the undersurfaces of laterally adjustable elongate plates 29 as seen in Figs. 7-8. In normal course of adjustment, the upper surfaces of movable plates 29 slidably engage the lower -surfaces 31 of plates 32. Plate~ 29 are supportably mounted on threaded adjusting rods 84 and 86 as seen in Fig. 8.
For purposes of forming the desired French fold right towel ~nel R may be first driv~n into overlying relationch;~ with the center panel C of th~ towel T
beneath the runners 28 by m~ans of a tim~d air blast emitted from air bar 30 illustrAtQd in ~ection in FigurQs 10-14. After the right towQl panel R i8 in proper overlying disposition as in FIG. 12, left air bar 30 is activated as illustratQd in Figure~ 12 and 13 to urge the left towel panel L into the overlying relation6hip illustrated in FIG. 14. ~1hho~ 21, 23 and 25 are pr(aferably surface treated with a plastic or othQr matQrial to facilitate ready r~lQasQ of ~ towel portion convQyed ther~by.
Part~cular attention should now be given to ov~arlying air-pQrvious grid 40. The grid may comprise an op~n air-pQrvious arrangement of intersecting rods as illustrated in FIGS. 11-13 and functions as a barrier surface against which the folding towel panels ride in the course of being urged by the air bla~ts into the folded configuration illustrated. In accor~nce with this invention the air-perviou~ grid 40 compris~ a stop surface ag~in~t which th~ towel panal being folded slldably moves in the course of b~ing folded about thQ
hinge linQs defined by the outermost ~dya~ of the ~o_~
runnQrs 28. The actual towel fold ~hinge~ comprise the intagral junctures of each sid~ panel of the towel T with the center panel C. As will bQ apparent from Figure~
13, the air emitted by the air bar~ 30 form~ elongate conc~vitiQ~ B on the under ide of each towel panel portion as the panel i5 being folded inwardly along the above-noted hinge lines. It has been found that in tha Ak-^noo -2~7~g A

_g_ of the stop surface provided by the undersurface of the grid 40, the towel panels are forced over the center panel and intervening runners 28 80 as to entrap air resulting in an undesired wrinkled appearance in which the longitudinal edges of the panels are not in desired parallel relationship with the longitudinal edges of the towel center panel in the manner illustrated in FIG. 14.
Without the controlled air exhaustion illustrated in Figures 11-14 there is also the possibility of the overlapping towel panel rebounding upwardly to deleteriously affect a desired edge alignment. A stop ~urface exemplified by the undersurface of the grid 40 may comprise any air-pervious surface through which air may readily pass upon the engagement therewith of the towel panel being folded.
The specific angular disposition of the air-emitting op~ni~gs such as openings 44 illustrated in air bar 30 fragmentarily illustrated in FIG. 9 may be readily adjusted by means of a set screw 46 threadedly mounted in a retention block 48 secured to the undersurface of a ~lide plate 32. A plurality of such mounting blocks 42 may be secured to the plate undersurfaces at spaced intervals as by means of apertured mounting brackets 50 seen in FIG. 9.
The interval between the undersurface of the air-pervious barrier 40 and the underlying plates 42 a~
well as the runners 28 may be adjusted by means such as a simple stud 52 and nut 54 arrangement illustrated in FIG.
`- 15. 8y way of example, an interval of three to three and one-half inches has been found satisfactory for the desired air exhaustion. Although the optimum interval will vary with the foldable article material density and weiqht, such interval may be readily empirically determined. The stud 52 of ~IG. 15 is vertically disposed on a mounting bracket 56 secured to a folder side frame in the manner illustrated in FIGS. 10-14. It will be noted from the latter Figures that the stud and nut arrangements are employed in oppo~ite pairs, and a minimum of four i8 normally needed to support apertured mounting tabs which may be secured to the grid 40 and adapted to be traversed by the studs 52. Lower adjusting nut 54 will precisely locate the grid on the stud after which upper nut 54 i8 threaded in place for purposes of securing the grid 40 in fixed position. Enlarged wachers~ not illustrated may be employed in conjunction with the studs and nuts to facilitate mounting of grid 40.
To accommodate towels of varying width, the int,erval between the runners 28 must be adjustable 80 that the size of the center panel C and resulting size of the sid* panels R and L may be adjusted by the operator. The adjustment is designed to form three longitudinal panels each of which is approximately one-third the width of the panel. The interval between the runners 28 i8 adjusted by means such as a reversible adjusting motor 60 illustrated in l~IG. 8. The latter rotatably drives chain or belt 62 clockwise or counter-clockwise whereby threaded rod 84 mounted in sprocket 78 i2 rotated. Chain 64 rotatably dri~es sprocket 70 on which the threaded adjusting rod 68 is mounted as more clearly seen in FIG. 8. It will al50 be noted from the latter Figure that in addition to the threaded rod 68, runner mounting blocks 72 and 70 engage the spaced, unthreaded guide rods 74 and 76 illustrated in FIG. 7.
Chain 62 of adju~ting motor 60 also rotatably drives sprocket 70 which rotatably engages chain 80 which in turn simultaneously drives sprocket 82. Mounted on the spaced sprockets 78 and 82 are threaded ad~usting rods 84 and 86 respectively. These two rods similarly to ~ 92/17633 21 0 ~

r I ~ = 3 3 . .: 1 1 adjusting rod 68 have right and left hand threads disposed on the opposed half portions thereof for purposes of engaging threaded mounting blocks 88 secured to the inner flange portions o~ the spaced adjustable air bar support plates 29 as clearly seen in FIG. 8. The threads are arranged on the rods 68, 84 and 86 so that rotation thereof uniformly adjusts the intervals between plates 29 and between blocks 70 and 72. It will be noted from Fig.
10 that runners 28 are a spaced-apart relation to define a maximum 3ize center towel panel C in the towel to be folded. In Fig. 10 air bars 30 and supporting plates 29 are at an outermost position 80 as to be desirably located adjacent the opposed outer runner edged as illustrated.
It will also be noted from Figs. 10-14 that towel-conveying ribbons 21, together with ribbons 23 and 25 are slidably movable over support plates 32 for the runner relative disposition illu~trated. Innermost ribbons 21 have the bottom runs thereof captured within guides 33 as clearly seen from Figs. 14 and 21. Thus when air-bar ~upport plates are adjusted inwardly into positions such as the innermost position illustrated in Fig. 21 with the runners 28 in abutting edge-to-edge engagement, ribbons 21 will also be inwardly moved because of the engagement with guides 33 secured to the depending flange~ of support plates 29 as illustrated.
The interval between the runners 28 may be set by the operator noting the size of the towels being folded and adjusting a control button, the latter will energize reversible adju3ting motor 60. The stop mean~ for the adjusting motor may comprise a simple ~ervo-mechanism partly illustrated in FIG. 7 comprising a rotatable potentiometer 89 engaging a belt 90, Anr~ored at opposed 210S76~

ends to plates 70, 72. A predetermined rotatable position of the potentiometer 89 corresponds to a desired interval between the plates 70 and 72 and runners 28.
Such servo mechanism thus comprises a belt-driven rotatable potentiometer 89 which is in a circuitbalancing the voltage of any of four selectable, adjustable potentiometers mounted in the folder control board. Each board-mounted potentiometer voltage correspond~ to a desired interval between the runners 28 for a particular towel size. When the operator indicates a towel size to be folded, ~he is in fact, setting a specific potentiometer voltage. The adjusting motor 60 i8 rotated in the proper direction until the belt-driven potentiometer 89 adjusts a bal ~ncing voltage which deenergizes adjusting motor, at which instant the runners 28 ,are at the desired interval to form the desired size towel panel.
In addition to the set intervals automatically provided by the operator-controlled means including the servo-mechanism 89, the interval between the runners 28 may be manually adjusted when towels or napkins of unusual wid~h are to be folded. The operator will then manually energize motor 60 by means of push buttons which change the interval between the runners 28 until the operator notes a de~ired runner interval. The maximum and minimum intervals between the plates 70 and 72 are determined by limit switches 92 illustrated in FIG. 7 having switch arms 94R and 94L. The outermost limit of plate movement is determined by engagement of switch arm 94R with arm 95 extending between the threaded adjusting rod and the guide rod 74. Arm 85 is stationary in the normal course of folder operation. Engagement of switch arm 94L with plate 72 determines the minimum interval between the runners 28.

-Also illustrated in FIG. 7 i8 a photo sensor 96 mounted on block 70 and optional twin photo sensor 97 illustrated in phantom line in FIG. 7, which may be mounted on outer wall of block 72 as illustrated.
The photo sensors employed in the folder 10 of this application are well known in the art and may comprise sensors sold under the tradename Micro-Switch, Model FE7B. The sensors emit a light beam which senses a towel or the like being folded and passing therebeneath as the sensed reflected light beam strikes the article being folded. Accordingly, the length of the centered towel which is fed onto the upper conveyor 14 of the folder 10 is automatically sensed for length with the assistance o~
a programmable controller which stores the impulses generated by the sensor 66 in conjunction with an electronic generator-counter device for generating counts or pulses ~tored in the programmable controller 98 of the block diagram of FIG. 20 as long as a foldable article i-Q
sensed.
In accordance with this invention the French fold formed by the runners 28 in conjunction with the opposed air bars 30 illustrated in FIGS. 11-14 may be formed as the towel is conveyed on the upper conveyor 14.
That is, the fold i~ formed as the towel is continuously moved by the ribbons of the conveyor.
In the event the towel is beyond a maximum length so that adequate time i8 not present for forming in sequence the overlapping folds illustrated in Figures 11-14 on conveyor 14, conveyor 14 is stopped. The programmable controller 98 upon receiving the length-determining pulses during towel sensing by the eye 96 of FIG. 7 will deenergize a clutch, disengaging drive sprocket 100 (See FIG. 18) from drive roll 22 of conveyor 14. It will be noted from FIG. 18 that chain 104 also ~ PCT/US92/02223 ~ -14- 21~769 engages underlying sprocket 106 of main drive roll 35 (FIG. 4) driving the underlying conveyor 26 moving in a direction opposite to conveyor 14, toward the folder feed-end. This relationship between the conveyors 14 and 26 is apparent from Figures such as 4 and 5 of the drawing.
It will be noted from FIG. 18 illustrating the drive chain and ~procket system~ employed in the provided folder 10, that although the upper conveyor 14 will stop when towels of beyond a maximum length are sensed, underlying conveyor 26 i~ continuously driven by sprocket 104. It will be noted from FIG. 18 that drive sprocket 106 of underlying conveyor 26 engages not only the chain 104 but in addition engages a ~econd drive chain 110 by means of a ~econd drive ~procket mounted behind sprocket 104 and not seen in FIG. 18.
Assuming that the towel length exceeds the r~Yirur length able to be folded while moving on upper conveyor 14; such towel is stopped until the folds of Figures 11-14 are formed. As a shorter moving towel will have the French fold formed before leaving the upper end of oonveyor 14, folder 10 need not be stopped. As a longer towel will be partially on the conveyor 14 and partially off the conveyor 14, if the latter were continuously moving, in the process of having the panels folded into the configuration of FIG, 14, it is necessary that the conveyor 14 be stopped to allow completion of the French fold. The two fold~ together require less than one~half second however it is intended that the conveyor speeds be of the order of 160 feet per minute.
It i~ obviou~ that in a shorter length towel the amount of air employed in forming the side panels over the center panel may not be as great as employed in folding a longer towel. The latter is normally also heavier, and ~T/US92/02223 yi292/17633 ~ - -15- 210~76~
; 5~8 a greater amount of air and air pre~sure is deemed n~c~ ry for forming the side panels over the center panel in forming a French fold. ~ccordingly, two Rets of air valves are ~r~ociated with an air compressor for allowing a lesser volume of air to form the French folds with smaller and normally lighter towel~ than i8 required for the heavier and longer towels which are folded after the same have come to rest. Thus FIG. 20 refQrs to first and ~con~ French air valve~ th~ solenoids of which are 10 activatad by controller 98 in accorA~n~ with the length of towel being folded. Coil 93 of the ~lst French air valve~ i8 seen in FIG. 20 as i8 coil 99 of '2nd French air valves~.

First Cross-Fold As the conveyor sp~d of the provided folder is of the order of 160 feet per minute, it will be noted from - FIGS. 4 and 5 that an appropriat~ gu$de such as guide fingers 112 is employed for guidins the folded towel being conveyed by the continuous ribbons 20 of upper conveyor 14 into a downwardly direction., Solenoid 113 of an air bar 114 i~ then activated 80 as to have air from bar 114 drive substantially the mid point of the Fr~nch folded towel into the bite of the overlying drive roll 22 of upper conveyor 14 and underlying roll 23 of underlying conveyor 26. Coil lol of the controlling solQnoid of thQ 1st cross air valve i8 referred to in FIG. 20. Air valve 113 controlling the emission of compr~ air through the air bar 114 i8 actuated with the assistancQ of a center photosensor 116 having di ~ to either side thereof misalignment photo ~n~ors 118 as seQn in Figures 1 through 3. If thQ French folded tow~l such as towel 1 illustrated in FIG. 1 i8 ~n~ by the photo sensor 116 and not by either photo ren~or 118 in the course of -16- 2105~69 dropping from upper conveyor 14, an air blast from air bar 114 is emitted as illustrated in FIG. 1 so as to drive the mid point of the French folded towel 1 into the bite of the opposed pinch rolls 22 and 23 of FIG. 4. The air valve solenoid allowing air to be emitted from the air bar 14 is activated by means of a signal from eontroller 98.
The photosensor 116 is 80 loeated relative to pinch rolls 23 and 26 that upon sending a signal to eontroller 98, one-half the length of the already-measured towel (travelinq at a known speed) is counted out after which the coil 101 i9 energized resulting in an air blast from bar 114 a3 illustrated in FIG. 1 to engage the longitudinal mid-point of towel 1.
It will be noted from FIGS. 1 and 4 that the cross folded and French folded towel 1 proceeds to the left on the ribbons of the underlying eonveyor 26 until engaging a seeond set of eurved guide fingers 112 whieh guide the end of the eros~-folded towel of FIG. 1 downwardly oppo3ite to air bar 122. In the event the towel 1 depending opposite the air bar 114 in FI~. 1 is mis~ligned, it will be sensed by either of the misalignment photosen30rs 118. A signal from a sensor 118 to eontroller 98 prevents the first eross air valve 113 fro~ being aetivated. The towel 1 i8 thus not folded and is guided by the guide fingers 112 into an underlying collection basket for proeessing.
If the eros~-folded towel 1 of FIG. l and proceeding to the left on eonveyor 26 is of a ~mall size the leading edge of the towel in the form lC in the eross folded stage is sen~ed by photo ~ensor 124 and the eoil of a seeond eross air valve 125 is aetivated to emit air from air bar 122 after the appropriate length of the sensed ero~s-folded towel is eounted out so that the leading edge of the sheet lC is driven onto the ribbons of conveyor 126 ~ - 2105~fi9 more clearly seen in FIG. 4. Conveyor 126 is continuously driven at sprocket 127 (FIG. 18) which engages chain 129 driven by sprocket 131 of the continuou~ly moving conveyor 23. Chain 129 also engages idler tensioning sprocket 133.
The top surface of the towel lC as illustrated in PIG. 1 and moving to the right is then driven onto the upper surface of a stack-forming trap door 128 one-half 135 of the trap door being illustrated in Figure~ 4 and 16. A~ the towel lC is moved onto the trap door 128 it i8 frictionally engaged by bottom runs R of the ribbons conveyor 130 ( FIG. 16) overlying trap door 128, until leading edge of the towel lC i~ ~ensed by a photo ~en30r 131 (see FIG. 1). Conveyor 130 preferably runs at a slightly greater speed than conveyors 14 and 26. Upon a signal from tr~p~oor photo sensor 131 to the controller 98, drive motor 146 ( FIG. 18) of conveyor 130 is stopped and after a short time delay, the coils 133 (FIG. 20) of the solenoids controlling trapdoor piston and cylinder units 132, one of which is fragmentarily illu~trated in FIG. 17 are energized ~o a~ to pivot straps ~uch as strap 134 illustrated in FIG. 17. Strap 134 actuates the toggle connections to the twin half doors 135, as the half doors 135 pivot around ~upporting rod~ 131 supportably mounted on support brackets 139 one of which is illu~trated in FIG. 16. A towel such as the illustrated towel lC of FIG.
17 compressed between the ribbons 22 of the conveyor 130 and the upper surfacea of the trap door halves 135 is then dropped substantially vertically onto sn underlyinq stack formed on an underlying return conveyor 140 also illustrated in FIGS. 4 and 6. The drive roller of the conveyor 140 is driven by a crosQ conveyor motor 141 of the block diagram of FIG. 20. The stacks of predetermined number such as seen in FIGS. 1 and 6 are carried by the ribbons of cross conveyor 140 after formation, onto the .j .~

ribbons of a horizontal eonveyor 142 which is driven simultaneously with adjaeent elevation eonveyor 144 by means sueh a~ a drive motor 146 as seen in FIG. 18.
Elevating eonveyor 144 of FIG. 6 deliver~ the staeked towels onto a platform 148 adjaeent to the folder operator at the feed end of the folder 10 whereupon the operator feeding the towel~ into the folder 10 may deposit sueh staeked towels into a cart for removal from the premises.
A~ noted above, the apparatus 10 is adapted to not only fold towels of varying length as the towels are either moving or as the towel~ are stopped, and in addition i~ adapted to form a variety of eros~ folds in a Freneh folded towel. Sueh flexibility enables the provided folder to ef f ieiently proee~s towels of a wide range of sizes, while effeeting a variety of fold~.
Thus in FIG. 2 a Freneh folded towel 3 whieh would normally be longer than the towel 1 of FIG. 1 i~
eross folded in the same r-nner as towel 1 of FIG. 1 and proceeds to the left in the form of a towel 3C whieh ha~
been Freneh folded and eross folded onee. A~ above described, the onee eross folded towelQ as proeessed by the apparatu~ 10 move toward the feed end of the folder on the underlying conveyor 126 and are appropriately urged onto the eonveyor 126 by air bar 122 after being guided about the lower guide fingers 112 and being sen~ed by sensor 124.
It will be noted from FIG. 2, however, that the towel 3C haQ its leading edge in engagement with lip L of support plate 150 more elearly 3een in FIG. 4. With the leading bight edge of the ero~ folded and Freneh folded towel 3C in the position of FIG. 2 resting on the lip L of the plate 150, air bar 122 is aetivated. The mid-point of towel 3C is then driven into the eonverging throat T (See FIG. 5) defined by the left end of conveyor 26 moving W ~ /17633 -lg- 2105769 about left roller 23L and by the conveyor 126 moving at the left about roller 131 and at the right about drive roller 133. The twice cros~ folded and French folded towel in the form of 3C2 of FIG. 2 is then driven by the bottom run~ of the continuous ribbons R of conveyor 130 after leaving the ribbons of conveyor 126 and being driven onto upper surface of the trap door 128 in the manner apparent from FIG. 16. Towel 3C2 i~ French folded and cross folded into guarters.
It will be noted from FIG. 20 that in accordance with the selection made by the operator of folder 10 in the selection of the "fold selector" the drive motor 60 is energized to move the attached runners 28 and the plates 32 into appropriate spaced apart relationship with the a~sistance of servo-mechanism potentiometer 89 of FIG. 7.
Similarly, in accordance with the particular type of cross-folds or folds desired in the French-folded towel, signals from the controller 98 will activate the air bars 114 and 122 after the appropriate fraction of the French folded towel has dropped in front of the openings 44. The air blasts will be emitted by in such air bars after the desired towel fraction has been "counted out" by the counter of the controller which occurs following sensing of such towel by the appropriate sensor 116 or 124 respectively.
Figure 3 illustrates a towel 3 which would normally be longer than the towel 1 of FIG. 1. If the machine operator had set the ~fold ~elector" input illustrated in FIG. 20 for a French-folded towel cross folded into thirds, the sequence of FIG. 3 would take place wherein the cross folded towel in the form of 3 depends on the end of the upper conveyor 14. A signal from the controller 98 following towel sensing by ~ensor 116 activates the air bar 114 so that the illustrated cr~ss fold is formed with approximately one-third of the to~el 3 remaining in engagement with the conveyor 14 and the runner~ 24 disposed thereover. The towel engagement with the runners prevents the entire towel 3 from falling from the end of the upper eonveyor 16 despite the fact that approximately two third~ of the towel 3 i8 hanging in the vertieal plane. On aetivation of the air bar 114 the towel in the form 3M moves to the left whereupon it is sensed by sensor 124 prior to moving onto ~upport plate 150. The eounter of the eontroller 98 will then emit a signal in response to the coun~er read out, opening the air valve 125 of air bar 122 ~o as to form the final fold as illu3trated in FIG. 3 dividing the Freneh folded towel 3M in half, now cross folded into thirds as it enters into the bite formed by the eonverging eonveyor belts 126 and 26 ~see Figures 4 and 5), until engaged by the bottom runs of tran~fer eonveyor 130 as previously deseribed. After the second eross old effected by the air bar 122 in FIG.
3, the folded towel in the form of 3M2 i3 sensed by photo sen30r 131 while being driven over the surface of the trap door 128 whereupon motor 102 driving conveyor 130 is stopped, and such eross folded, Freneh folded towel is dropped vertieally onto the partially formed staek illustrated.
It has been found that preeisely formed staeks may be moved without twisting or misalignment upon being diseharged from eros~-conveyor 140 illustrated in FIG. 6 onto conveyor 142 prior to being plaeed upon elevating conveyor 144 for arrival at platform 148. The teehnique of avoiding any misalignment requires that the upper suraee of eros~ eonveyor 140 be disposed slightly aboYe the level of eonveyor 142 enabling the formed staek sueh as the two staeks illustrated in ~IG. 6 to be partially in overlying relationship with the rihbo~ of conveyor 142 :

-PCT/US92/022~3 W ~ 2/17633 ' .~ ri ;
t 210576~

. while the majority of the area of the bottom towel of the stack rests upon the ribbons of conveyor 140. Upon - actuation of the conveyor 140 to move the formed stack onto the ribbons of conveyor 142, stack S2 will in fact push the stack S completely onto the ribbons of conveyor 142 without any portion of stack S remaining on conveyor 140. As a result, when conveyor 142 is actuated to move in the direction of the shelf 148 on conveyor 144, stack S
moves axially without any twisting or turning occasioned by being partially on conveyor 142 and partially on conveyor 140.
The provided folder 10 also poase~ses a jam detector 152 indicated in FIG. 20. Such jam detector is actuated to cut off the electrical power to the apparatu~
10 if a towel sensed by the first photo ~ensors does not arrive at the following photo sensors within predetermined time limits. Such failure to arrive is evidence of jamminq or other malfunction which may have occurred and accordingly the electrical power input to the main drive motors is terminated on the expiration of any interphoto-sensor time interval pre-set in the controller which i5 based on the known time interval which tran~pires in towel movement through folder.
.~ Figure 20 al~o illustrates a reject button which is actuated by the operator who may notice a defect in a towel being fed into the folder after.the initial portion of the towel has already passed onto the upper feed conveyor 14. Upon noticing such defect the operator merely pu~hes a reject button which inactivates the first cros~ fold air valve 113 and as a result no air is emitted - by air bar 114 allowing the towel to drop into an underlying collection basket.
--22- 2~769 t Folder lO is adapted to merely longit~ ly fold a small towel or large ~A~ n in half and avoid a French fold formation wherein a towel i~ folded longit~ ly into panels of approximately one third the width of the towel. Such fold is effectQd by centering a Dmall towel 80 that the fold linQ is coincident with the outer edge of one runner 28 only of the apparatus lO.
Such an arrangement may employ a pair of photoA^~ors 96 and 97 rather than a s$nglQ photo ~Aor 96 as would no~ally be employed when a French fold is to be formed on th~ towels being pL 0~ 'AeA When Qmploying th~ two fold photo sen~ors 96 and 97 of FIG. 7 each photo sensor controls the air valve for it8 respective air bar disposed ad~acent a runner 28. Accordingly if towQls of normal widlth are fed into the apparatus lO both ~A~nrors are actuated and two air valvQs are actuated in con~unction with the two runnQrs and air bars 80 that the French folds of FigurQs l, 2, 3 may be formed in tha mannQr above de~cribed. If, howQver, a tow~l i8 fQd into the apparatus 2 0 50 as to bQ FenA^~ by one photo ~o~Aor only and i5 al80 centered 80 that the fold line of the half fold being formed i8 as shown in FIG. 18 is alignQd with the central axi~ of thQ towel, one air bar only will be actuated a~
illustrated to form the half fold in conjunction with a singlQ runner. The half folded nAp~n or towel H
illustri~tQd in FIG. 9 may i f desirQd ~L~ through the rami~n~n7 apparatus for a cros~ fold se~-~ce.
It i~ apparent that all cros~ folds ~ay be eliminated by programming the air bars 80 as to force the l~Ai~ng edge of the half folded or French folded towels int~ the bite of the counter rotating rolls of the conveyor sy~tems illustrated as th~ foldablQ articlQ
proc~ through the se~ence of conveyors onto the trapdoor 128.

_ W ~2/17633 It i8 thus seen from the foregoing description that a novel towel folder or the like has been provided which forms precise folds in a rapid manner. The folds although being formed instantaneously are controlled ~o as to completely exhaust the air from the towel side panels in the course of being instantaneously folded over an underlying runner and center panel. The manner of controlled folding provided whereby the folding panel slides against an overlying air-perviou~ guide surface assures the desired exhaustion of air and ab~ence of bubble formation in the overlying panels of the French fold formed. Benefits provided by the novel fold forming apparatus of this invention become increasingly important if finely w~ven fabric~ are folded which are more susceptible to air entrapment. Although a plurality of controlled folding opetations have been described, the elementQ necessary for the various variety of folds described are readily available. The microcontroller 98 may be a shelf item such as a Model No. F2-40 MRVR
manufactured by Mitsubishi Electric Corp. The circuitry employed in conjunction with the microcontroller board i8 not advanced as inventive per se, the circuitry employed in forming the cro~s folds being known to the art and ~imilar to that de~cribed in co-pending Kober et al.
application seriaI no. 07/480716 assigned to the assignee of the subject invention, and the disclosure which is incorporated herein by reference. The provided apparatus in addition to forming a French fold in foldable piece~
~which may be tran versely folded into quarters or thirds or other desired fraction, i5 al~o adapted for the folding of foldable flat pieces longitudinally in half.
The provided apparatus although simple in construction is rugged and durable and able to run at high speed for extended time periods. The ability of the folds W O 92/17633 PC~r/US92/02223 ~es~ribed to be formed in articles while moving or at rest enables the folder to efficiently process a wide range of article sizes, thereby emphasizing the versatility of the folder of this invention.
It is believed that the foregoing detailed description has made apparent to those skilled in the art a number of variations and modifications that fall within the ~oroad ambit of the invention disclosed. Although the foregoing description has been somewhat specific to the folding of towels of various sizes, other items of laundry flatwork may be processed by the folder described. Such items by way of example and not limitation include hospital gowns, napkins and small sheets. It is intended therefore that this invention be limited only by the scope of the appended claims.
What is claimed is:

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR
PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A folding apparatus comprising conveyor means for moving a foldable article along a path of movement; air discharge means disposed adjacent said conveyor means for laterally discharging air to substantially instantaneously fold a panel of a foldable article on said conveyor means;
said panel extending from a hinge axis to a distal end and being urged by said air discharge means into overlying relation with a connected portion of such foldable article to which it is joined along such hinge axis; fold control means for controlling the folding of such panel relative to the article connected portion and comprising a barrier disposed over the conveyor means in adjacent relationship therewith whereby laterally discharged air from said air discharge means urges a proximal portion of the panel extending from the hinge axis, downwardly against the conveyor means, and simultaneously upwardly urges a trailing portion of said panel into slidable engagement with said barrier which limits the upward movement of such panel relative to said conveyor means; the discharged air forming a laterally moving concavity in a panel portion interconnecting the panel proximal and trailing portions; the interval between said conveyor means and said barrier being substantially uniform to enable such cavity-forming air to laterally move the panel in a substantially uniform manner as the proximal panel portion rolls over the article connected portion until the panel distal portion disengages from the barrier and is driven onto the surface of the underlying connected portion of the foldable article.

2. The folding apparatus of claim 1 in which said conveyor means has a first portion for conveying the foldable article connected portion and a second portion for conveying the foldable article panel above the foldable article connected portion, the article portions being joined by a connecting portion disposed at such hinge axis; said air discharge means being positioned for discharging air at the foldable article connecting portion.

3. The folding apparatus of claim 1 in combination with means for measuring the length of a foldable article moving along the path of movement; control means responsive to such measuring means for controlling the discharge of air through said air discharge means while said conveyor means is moving when said measuring means measures a foldable article having a length less than a predetermined maximum article length; the responsive control means stopping said conveyor means when said measuring means measures a foldable article having a length greater than a predetermined maximum length and controlling the discharge of air through said air discharge means with said conveyor means in the stopped condition.

4. The folding apparatus of claim 3 in which said barrier is air permeable and said apparatus is in further com-bination with spaced edge-defining means located adjacent the foldable article path of movement; said air discharge means being spaced and associated with said edge-defining means and located beneath spaced second portions of said conveyor means for conveying spaced foldable article panels along the path of movement, said conveyor means second portions being spaced apart by said conveyor means first portion for conveying an intermediate foldable article portion; the control means responsive to the measuring means controlling the discharge of air in sequence through said spaced air discharge means whereby opposed panels of a foldable article are folded in sequence over the edge-defining means and over the foldable article intermediate portion.

5. Folding apparatus for foldable articles comprising a first conveyor means; edge-defining means disposed adjacent said first conveyor means; said first conveyor means being adapted to move a first portion of a foldable article disposed thereon beneath said edge-defining means; second conveyor means for conveying a lateral portion of a foldable article at an elevation above a foldable article first portion disposed on said first conveyor means; air discharge means disposed adjacent said second conveyor means for substantially instantaneously folding a lateral foldable article portion over said edge-defining means; such lateral portion extending from a proximal end where connected to the foldable article first portion to a lateral portion distal end; and means for controlling the movement of lateral foldable article portions over said edge-defining means; the movement controlling means being disposed relative to said second conveyor means whereby a lateral foldable article portion on said second conveyor means is folded over said edge-defining means by said air discharge means and urged into slidable engagement with said movement controlling means as the proximal end of such lateral portion disposed adjacent said edge-defining means is urged downwardly into surface-to-surface contact with upper surface portions of said edge-defining means; said air discharge means and said movement controlling means effecting a substantially instantaneous rolling, folding action of a foldable article lateral portion, progressing continuously in a substantially uniform manner from the lateral portion proximal end where engaging said edge-defining means to such lateral portion distal end.

6. The folding apparatus of claim 5 in which said second conveyor means are disposed on opposite sides of said first conveyor means, an air discharge means being associated with each of said second conveyor means; said apparatus being in further combination with means operatively connected to said air discharge means whereby such associated air discharge means discharge air in sequence and opposed lateral portions of a foldable article disposed on opposite sides of said first conveyor means and on said second conveyor means are folded in sequence over a foldable article first portion disposed on said first conveyor means; a second folded lateral portion of sequentially folded lateral portions of a foldable article slidably engaging said movement controlling means while progressively rolling in surface-to-surface engagement over a first folded lateral portion of a foldable article from a proximal end of the second folded lateral portion where initially engaging said foldable article first portion to a distal end thereof.

7. The folding apparatus of claim 5 in which said movement controlling means is apertured, said second conveyor means comprises continuous ribbons moving over fixed supporting plates, and said first conveyor means comprises a continuous ribbon moving at the speed of the continuous ribbons of said second conveyor means.

8. The folding apparatus of claim 7 in which said edge-defining means comprise spaced runners; said apparatus being in further combination with spaced movable support means slidably movable beneath said fixed plates; the intervals between said runners and between said support means being simultaneously adjustable.

9. The folding apparatus of claim 7 in which said continuous ribbons moving over said fixed plates are surface coated to facilitate release of foldable article lateral portions carried thereby from said ribbons and into overlying relation with a foldable article portion on said first conveyor means.

10. The folding apparatus of claim 9 in which one of said continuous ribbons is retentively guided by each of said movable support means and said air discharge means are secured to opposed edge portions of the under surfaces of said movable support means.

11. Folding apparatus comprising conveyor means for moving a foldable article along a path of movement; spaced edge-defining means disposed adjacent said conveyor means; air discharge means associated with each of said edge-defining means for discharging air to substantially instantaneously fold lateral portions of such foldable article about said edge-defining means; means for controlling the discharge of air in sequence through said air discharge means; barrier means for controlling the folding of each lateral portion of such foldable article and located adjacent the foldable article path of movement and said edge-defining means; said air discharge means urging lateral portions of such foldable article over said edge-defining means, into slidable engagement with the fold controlling means as air is progressively exhausted from beneath each lateral portion from said edge-defining means about which folded to a lateral portion distal end; said foldable article lateral portions being rolled into engagement with underlying support surfaces provided by said edge-defining means and such foldable article in surface-to-surface relationship while slidably engaging said fold controlling means; underlying conveyor means disposed beneath the first conveyor means and moving in a direction generally opposed to that of the direction of movement of said first conveyor means; said first and underlying conveyor means comprising continuous ribbons moving about opposed rolls;
superposed rolls of said first and underlying conveyor means disposed at the end of said first conveyor means defining counter-rotating pinch rolls; second air discharge means oppositely disposed to said counter-rotating pinch rolls for urging a desired transverse portion of a foldable article dropping from the end of said first conveyor means into the bite of said counter-rotating pinch rolls; means for measuring the length of a foldable article while moving on said first conveyor means operatively connected to said second air discharge means; means for sensing the leading edge of a foldable article upon moving from said first conveyor means, and means for activating the second air discharge means responsive to said measuring means and sensing means.

12. Folding apparatus comprising means for moving a foldable article along a path of movement; air discharge means disposed adjacent said path of movement for substantially instantaneously folding a lateral panel portion of such foldable article extending from a hinge axis to a distal end of such panel portion about said hinge axis into overlying relationship with a connected portion of said foldable article; said air discharge means being disposed above the path of movement of such foldable article connected portion;
edge-defining means for forming such hinge axis disposed adjacent such foldable article path of movement; said means for moving a foldable article comprising a first conveyor portion for moving a first foldable article portion along a first plane and a second conveyor portion for moving a panel portion of such foldable article connected to said first foldable article portion in a second plane disposed above the first plane; said edge-defining means being disposed between said first and second planes; means disposed adjacent the path of movement of such foldable article for controlling the folding of such panel portion relative to such article connected portion when folded by said air discharge means about said edge-defining means; the fold controlling means being so disposed relative to the path of movement of such foldable article whereby such foldable article panel portion slidably engages said fold controlling means when urged by said air discharge means into overlying relationship with a connected portion of said foldable article and air is substantially instantaneously exhausted from beneath the panel portion of such foldable article from the hinge axis to the panel portion distal end and such panel portion is rolled over such underlying connected portion of such foldable article with an air induced downward bias from the hinge axis to the panel portion distal end.

13. The folding apparatus of claim 11 in combination with a third conveyor means disposed beneath and at the end of the underlying conveyor means; rolls disposed at the end of the underlying conveyor means and at the beginning of the third conveyor means comprising a throat into which a cross folded foldable article may pass upon dropping from said underlying conveyor means and moving onto said third conveyor means; third air discharge means oppositely disposed to said throat;
foldable article sensing means for sensing a foldable article disposed adjacent said throat and in operative communication with said third air discharge means for activating said third air discharge means when a pre-selected transverse portion of a foldable article is disposed opposite said throat.

14. The folding apparatus of claim 13 in combination with stacking means comprising smooth support surfaces for such foldable articles disposed at the end of said third conveyor means, and a fourth conveyor means of continuous ribbons having upper and bottom runs and mounted above said stacking means whereby a foldable article driven by said third conveyor means onto said smooth support surfaces is engaged by the undersurfaces of the bottom runs of the ribbons of said fourth conveyor means and slidably driven over said smooth support surfaces.

15. The folding apparatus of claim 14 in combination with second foldable article sensing means disposed in the path of movement of a foldable article over said smooth surfaces; means for moving said fourth conveyor means and means responsive to said second article sensing means for deactivating said means for moving said fourth conveyor means.

16. The folding apparatus of claim 15 in which said smooth surfaces are movable to drop a foldable article thereon in the vertical plane after the means for moving said fourth conveyor means is deactivated.

17. The folding apparatus of claim 16 in combination with fifth conveyor means for receiving and moving articles dropping from said smooth surfaces and moving such articles from beneath said smooth surfaces.

18. The folding apparatus of claim 17 in which said fifth conveyor means includes a first conveyor member disposed beneath said smooth surfaces for moving a foldable article from beneath said smooth surfaces to a position in which one peripheral edge portion of such foldable article is disposed exteriorly of said folder and a second conveyor member disposed beneath the level of said first conveyor member for conveying foldable articles received thereon to a location adjacent the feed end of said folding apparatus.

19. The folding apparatus of claim 18 in combination with counter means associated with said smooth surfaces and said first conveyor member for allowing movement of said first conveyor member after a predetermined number of foldable articles has dropped into a stack on said first conveyor member; each stack of foldable articles being pushed from said first conveyor member completely onto said second conveyor member by a following stack of foldable articles moved by said first conveyor member.

20. Folding apparatus comprising conveyor means for moving a foldable article along a path of movement and comprising a first conveyor portion for moving a foldable article first portion in a first plane, and a second conveyor portion for moving a second foldable article portion connected with such first foldable article portion in a second plane;
edge-defining means for forming a hinge axis between foldable article portions and disposed in a plane between the planes of said conveyor means first and second portions adjacent such article path of movement; air discharge means disposed between said first and second planes adjacent each edge-defining means for substantially instantaneously folding a second foldable article portion on said second conveyor portion about said edge-defining means and over a first foldable article portion on said first conveyor portion; means disposed adjacent said first conveyor portion for controlling the folding by said air discharge means of a foldable article second portion relative to a foldable article first portion; said air discharge means urging distal portions of such foldable article second portion into slidable engagement with the fold controlling means when urged into overlying relationship with a foldable article first portion as proximal portions of the foldable article second portion disposed at such edge-defining means are downwardly urged and simultaneously rolled over such underlying first portion of such foldable article from the hinge axis between the foldable article first and second portions, to a distal end of such foldable article second portion.

21. The folding apparatus of claim 20 in which the fold controlling means is air permeable.

22. The folding apparatus of claim 20 in which support surface means slidably engage said second conveyor portion and said air discharge means is secured to an undersurface portion of said support surface means and emits an air discharge directly into the interval between the planes of said first and second conveyor portions.

23. The apparatus of Claim 12 in which said air discharge means is disposed between said first and second planes and above said edge defining means.

24. The apparatus of claim 23 in which the fold controlling means is air permeable and said air discharge means discharges air at right angles to the interval between such first and second conveyor portions.