SHEET FOLDER

Abstract: A problem encountered in the folding art deals with the folding of different sizes of sheets so as to produce substantially uniformly sized and oriented bundles. The instant invention purposes to solve this problem by utilizing an apparatus wherein sheets (15) are moved in an unfolded condition along their lengths on a horizontal conveyor (36, 38) grasped at the opposite sides of their leading edge, stretched at their leading edge and fed into a nip roll (70) of a folder. The nip roll progressively moves the sheet down an inclined guide plate (100) toward first and second clamp assemblies (108 & 109). The clamp assemblies alternately grasp and draw the sheet forward thereby folding the sheet in an accordion fold (29). The sheet is then conveyed along its folded length out the ends of the two clamp assemblies to a winding fork (160) where the accordion folded sheet is grasped by and folded about the winding fork in a flat spiral configuration and then is moved off the ends of the tines of the winding fork.

Description: Description "SHEET FOLDER" Technical Field This invention relates to a method and apparatus for forming bed sheets and the like first in an " accordion folded configuration and then In an approximately flat spiral folded configuration for packaging and merchandizing. Background of the Invention Bed sheets and similar mass produced items such as bedspreads, curtains and table cloths are usually folded into an attractive,, dense package, with the label of the product exposed for inspection by the potential customer. Sometimes the sheet is wrapped in a transparent package. Because the sheets, etc. are manufactured in different sizes, it is desirable to fold the different size sheets in different ways so that the packages formed by the sheets are approximately the same length and width, regardless of the size of the shee.tt This means that a smaller sheet will have fewer folds than a larger sheet. For example, a sheet, for a "single" bed narrower than a sheet for a larger "twin", "queen" "king" size bed, and while the single size sheet m have as many folds across its length as the oth size sheets, it is likely to have fewer folds acro its width. Various techniques have been developed f folding sheets, including various hand and automat techniques. For exa ple f a sheet may be fold across its length, then across its width, and aga across its length, or a shee may be folded sever times across its width to form an elongated shap and then folded several times across its length * some instances, particularly when automated foldi equipment is utilized, a sheet may be wound in tube f the tube flattened, and then the flattened tu folded across its length. Hand folding of sheets and the like cumbersome and slow because of the large expanse material that must be handled by the workers. ' Whi various automated folding apparatus has be developed for folding sheets and the like, they a large and require a substantial amount of flo space, the apparatus is expensive, and in so instances, the operation of the apparatus is slow a requires a substantial amount of operator time. Summary of the Invention Briefly described, the present inventi comprises a sheet folding method and apparat wherein a bed sheet or similar flat article . processed through a series of steps, first into pleated or flat accordion folded configuration, a next the sheet in it.s flat accordion fold configuration is wound into a substantially fl /- iU spiral package. The system is constructed so that the sheet can be taken from a horizontal conveyor line where its edges have been hemmed, the leading edge of the sheet grasped and stretched into a substantially flat configuration, and the flat leading edge passed to a nip roll which feeds the sheet down an inclined guide plate. The leading edge of the sheet is grasped by a first elongated clamp assembly, the nip roll terminates its function, and the sheet is then -spread away from the first clamp assembly into a facing second clam assembly. The sheet is held by the second clamp assembly while the first clamp assembly releases the sheet, and then the sheet is spread in the oppos te direction away from the second clamp assembly back toward the first clamp assembly, whereupon the first clamp assembly re-engages the sheet and the second clamp assembly releases the sheet. The clamping and spreading steps are repeated until the entire length of the sheet is drawn into the clamps, whereupon the sheet is forme in a pleated or flat accordion folded configuration. The sheet is then moved along the ' length of the clamps and into the tines of a winding fork positioned at one end of the clamps. The winding fork rotates and winds the accordion folded sheet onto its tines in a substantially flat spiral configuration. The sheet is then pulled off the ends of the tines of the winding fork and is ready for wrapping and shipment to the retail merchant, etc. The sheet folder apparatus includes a pair of spreader plates that oscillate' in unison, with the first spreader plate positioned over .the first elongated clamp assembly and movable into and out of the opposite facing elongated clamp assembly, and the second spreader plate positioned over the second elongated clamp assembly and movable into and out the first facing elongated clamp assembly. The s is guided from above the spreader plates down i the clamps, and each spreader plate moves into plane of the sheet and spreads the sheet over to opposite clamp assembly, where the clamp assem grasps and holds the sheet while permitting spreader piate to be withdrawn from the cl assembly. This back and forth motion of the spre ° plates into and out of the clamp assemblies forms - sheet in an accordion folded or zig-zag plea configuration. Thus, it is an object of this invention provide a sheet folder system which forms bed she 5 a nd similar articles in a- neat accordion fol configuration. Another object of this invention is provide a sheet folder system which expediently reliably folds bed sheets and similar articles fi 0 in an accordion folded configuration and then wi the accordion folded sheet into a substantially f spiral folded configuration. Another object of this invention is provide apparatus for folding sheets and simi 5 items, said apparatus being constructed in a comp configuration so as to occupy a minimum of w space. Other objects, features and advantages the present invention will become apparent u 0 reading the following specification, when taken conjunction with the accompanying drawings. Brief Description of the Drawings Fig. 1 is a schematic illustration of 5 method of feeding and folding sheets. _ Fig. 2 is a schematic perspective illustration of the sheet folder. . Fig..3 is a- schematic-side .elev.ational view of the sheet folder. 5 Figs. 4A, 4B, 4C, 4D, 4E, 4F and 4G are - -progress iv-e- schematic i-1-lus rat±σns of the- process of folding a sheet into an accordion fold. Fig. 5 is a side elevational view of the winding assembly which forms the sheet in a 1° substantially flat spiral folded conf iguration * Fig. € is a detail perspective illustration of a portion of the winding assembly and an end portion of the accordion folding assembly, with the winding fork oriented in a vertical attitude. 15 Fig. 7 is a schematic end view of the winding assembly of Fig. 5, with th winding fork rotating through a vertical attitude. Fig. 8 is a top view of the winding assembly of Fig. 5, with the winding fork oriented in 20 a horizontal attitude. Fig. 9 is an electrical schematic of the infeed section of the accordion folding portion of the sheet folder. Fig. 10 is an electrical schematic of the 25 accordion folding section of the sheet folder. Fig. 11 is an electrical schematic of the winding fork assembly section of the sheet folder. Detailed Description 30 Referring ,now in more detail to the drawings,- in which like: numerals. -indicate like parts throughout the several views, Fig. 1 illustrates the manner in which a bed sheet 15 or a similar flat item is -folded, wherein the bed sheet, moves in the 35 direction indicated by arrow 16, for example through _ sewing machines 18 and 19 which hem the opposite s edges 20 and 21. The leading edge 22 was previou hemmed in another stage (not shown) of the syst The side edges 20 and 21 of the sheet 15 are gras 5 at a positions adjacent the leading edge 22 as sheet 15 moves off the horizontal conveyor (n shown), the leading edge of the sheet is stretc and then moved into the sheet folder. The movem of the leading ' edge of the sheet is delay 10 momentarily so as to permit the following portion the sheet 15 to accumulate at 24, by moving under influence of gravity as indicated by arrow 25 t lower ' level. The leading- edge of the sheet is t - fed as indicated by arrow 26 on into the accordi 15 - folding assembly. The sheet moves down an incl 28> is folded into an accordion folded con igurat or 2-shaρed configuration, and the sheet then moved along its folded length as indicated by ar 30 to a winding fork which winds the accordion fol 20 sheet into a substantially flat, spir configuration, by rotating the sheet as indicated . arrows 31 on the winding fork. The label 32 and h hem 34 become located on the outer surf act of folded sheet so that they can be inspected by 25 ultimate customer, etc. As illustrated in Fig. 2, the sheet fol 35 is located at the end of a horizontal conveyor represented by the conveyor tapes 36 and 38. photocell 39 and 40 is located at each side ed 30 portion of the path- through which the sheet travels on the horizontal conveyor so as to det the presence of the oncoming leading edge 22 of sheet. Sheet folder 35 includes stationary supp 35 frame 41 (only partially illustrated in the drawin BU O Wi that supports its various operational elements, and movable support frame 42 that is pivotally connected at its " lower end to the stationary support frame 41. The movable support frame includes side legs 44 and 45 and cross bar 46. A pneumatic cylinder 48 is supported at each end of the stationary" support- rame 41 and the cylinder rods 49 of the cylinders 48 are connected to an extension 50 on each side leg 44 and 45 of the movable support frame, so as to swing the cross bar 46 from the end of the conveyor over to the sheet folder 35. A spring assembly 51 is also mounted at each end of stationary support frame 41 1 and each spring assembly 51 includes a rod 52 pivotally attached at one of its ends to a side leg of the movable support frame 42 and slidable through a collar 53 of the stationary support frame. Collars 54 and 55 are attached to rod 52, and coil compression springs 56 and 57 are positioned between collars 54 and 53 and between collars. 55 and 53, thereby biasing the rod 52 and movable support frame 42 to a intermediate position between the conveyor and the sheet folder 35. Thus, cylinder 48 mus positively urge the movable support frame 42 either toward the conveyor or toward the sheet folder while the springs 56 and 57 tend to bias the movable support frame to an intermediate position. The cross bar 46 of the movable support frame 42 supports a pair of finger clamp assemblies 56 and 58, Each finger " clamp assembly includes a mounting bracket 59 connected to cross bar 46, the mounting bracket 59 including means such as set screw 60 for permitting the mounting bracket to be moved to different positions along the length of the cross bar 46, Pneumatic cylinder 61 is held by mounting bracket 59, and C-shaped bracket 62 is supported by and is movable with the cylinder rod 64. A pair o grasping fingers 65 and 66 are supported in eac C-shaped bracket 62, with the lower finger 65 bein rigidly connected to each C-shaped bracket and th upper finger 66 supported by cylinder rod 68 o second cylinder 69. The open end of each C-shape bracket 62 faces inwardly along the length of cros bar 46, and the finger clamp assemblies 56 and 58 a each positioned on the cross bar at locations wher the grasping fingers 55 and 56 are aligned with th - side edge portions of an oncoming sheet 15. Cylinders 61 and 69 of the finger clam assemblies 56 and 58 are actuated by photocells 3 and 40. When the photocells detect the oncoming edg of a sheet on the conveyor, the movable support fra 42 is located at the end of the conveyor and th cylinders 69 close the grasping fingers 65 and 6 about the oncoming edge portions of the sheet, .so a to grasp the sheet at its opposite side edges adjacent the leading edge. The cylinders 61 are als energized so as to spread the grasping fingers awa from each other across the -length of the sheet, so a to stretch and maintain the leading edge portion o the sheet 15 into a substantially flat con iguration Kip roll 70 is rota table about a horizonta axis 71 and is supported by the stationary suppor frame 41 (not shown) just above the path of movemen of the leading edge of the sheet 15 into the ' shee folder 35. Nip roll 70 is powered by a motor (no shown) which is connected to the zero-ma transmission ' 72 and through connecting drive belt 74 Lever 75 of the transmission is pivotal and function in a conventional manner to change the output of th belt drive 74 from zero velocity to a predetermine angular velocity. Pneumatic cylinder 76 has it _ cylinder rod 78 connected to lever.75, so that distension and retraction of rod 78 by cylinder 76 turns lever '75 and functions to cause- nip roll 70 to rotate or stop rotation. 5 Sheet feed plate assembly 79 includes a - • -support bar 80 ig idly mounted' at"its- ends to levers 81. Levers 81 are pivotally supported at 82 to stationary support frame 41 (not shown), so that the support bar pivots about the lower ends of the levers 10 81. Pneumatic cylinder 84 is mounted on the support frame and its rod 85 is connected to the ends of support bar 80, so as to oscillate support bar 80 as indicated by the double-headed arrow 86. Sheet feed plate 88 extends over the upper surface of support 15 bar 80 and includes one edge portion 89 that is rigidly connected to a surface of support bar 80, while the remainder of the sheet feed ' plate extends rearwardly from the support bar 80 beneath nip roll 70. Since the support bar 80 is offset forwardly of ■ 20 the nip roll 70, the sheet feed plate 88 is movable in an upward arc toward engagement with the lower surface of nip roll 70 when the support bar 80 is moved to the left by cylinder 84, and when the cylinder 84 allows the support bar 80 to move to the 25 right, the sheet feed plate moves in an arc downwardly away from the lower surface of nip roll 70. As illustrated in Fig. 3, when the movable support frame 42 swings over to sheet folder -35, the 30 grasping fingers 65 and 66 carry the leading edge of the sheet IS into -the space between sheet feed plate 88 and nip roll 70. When the movable support frame 42 reaches this position, a switch 89 is engaged by - -- - the- movable support frame 42. -Switch 89 actuates 35 cylinders 84 at the end of support bar 80 to lift — sheet feed plate 88. toward engagements with nip ro 70, to press the leading edge portion 22 of the she into frictional engagement with the nip roll, Als switch 89 actuates pneumatic cylinder 76 whi controls the zero-max transmission 72 and begins t rotation of nip roll 70 in the direction indicated arrow 90, to feed the sheet on into the sheet fold ' 35. Switch 89 also deactuates cylinders 62 and 69 the finger clamp assemblies 56 and 58, causing t 1° fingers of each pa'ir of grasping fingers to ope - Switch 89 also causes the pairs σf grasping finge to move closer together, and reverses cylinder 48 return the movable support frame back to t conveyor. Thus,- the sheet 15 is now moving under t I 5 influence of nip roll 70 and. its sheet feed plate on into the sheet folder. A plurality of pivotal friction plates are positioned adjacent nip roll 70 across the wid of the sheet folder 35. Each friction plate 20 attached at its upper end to friction plate suppo bar 92, the friction plate support bar 92 bei pivotally connected at its opposite ends by t stationary support frame (not shown). Friction pla cylinders 94 are positioned at opposite ends of t 2 friction plate support bar 92 and their cylinder ro 95 are each connected to levers 96. Levers 96 a connected to the ends of the support bar 92, so th when cylinders 94 are actuated they pivot support b 92 as indicated by the double-headed arrow 98, th ^ causing the friction plates 91 to move as indicat by double-headed arrows 99. A downwardly inclined sheet guide plate 1 extends across the width of sheet folder 35 a includes a rectal inear upper edge 101 located benea 5 sheet feed plate 88 and a rectalinear lower edge 10 _ The friction plates 91 are creased at 104, so that the upper portion 105 of each friction plate 91 extends at a steeper downward angle from the friction plate support bar 92 and then turns to a more shallow ' 5 incline at 106 which is parallel to the plane of guide, plate 100 when the friction plates 91 rest against the guide plate. A resilient support rod 105 is supported at its ends by the stationary support frame (not shown) and functions to hold guide plate 10 100 in its proper position and at the same time to permit the friction plates 91 to bounce against guide plate 100 without damaging the guide plate. A pair of elongated, parallel sheet clamp assemblies 108 and 109 are located beneath guide 15 plate 100. The sheet clamp assemblies 108 and 109 are identical in construction and are arranged with their clamp openings spaced apart and facing each other. The sheet clamp assemblies 108 and 109 each include upright wall section 110, stationary lower 20 clamp element 111 mounted on wall section 110, movable support beam 112, and upper clamp plate 114 mounted on support beam 112. A plurality of pneumatic cylinders 115 are mounted on upright wall section 110 at spaced intervals along the width o 25 the assembly by means of brackets 116, and the cylinder rods 118 are each connected to clamp beams 112. Thus, the clamp beams 112 and the upper clamp plates 114 reciprocate by the action of cylinders 115 as indicated by double-headed arrows 119. A tubular 30 gasket 120 is mounted in an elongated recess 121 extending along the bottom surface of each upper clamp plate 114 at the facing edges of the two clamp plates 114. Sheet support plateforms 122 and 124 are 35 mounted on the stationary lower clamp elements 111 of __ each sheet clamp assembly 108 and 109 and ext horizontally inwardly from each clamp assembly tow one another in a common plane. A gap 125 is for between the sheet support platforms 122 and 124, 5 that the sheet clamp assemblies 108 and 109 can moved toward or away from each other so that folds to be made in the sheets can be larger smaller. A pair of sheet spreader or fold plates 10 and 129 are located above the sheet clamp assembl 108 and 109 with the first sheet fold plate 128 be located above the first sheet clamp assembly 108 the second sheet fold plate 129 being located ab the second sheet clamp assembly 109. Fold pl 15 guide bars 130 and 131 are also located above sh clamp assemblies 108 and 109, and fold plates 128 129 rest on and move across guide bars 130 and 1 The outer, upper edges of the fold plates 128 hingedly connected to the upper ends of fold pl 20 drive levers 132 and 134, and the lower ends of levers 132 and 134 are pivotally mounted stationary support frame 41. Connecting rod 135 connected at its ends to each of fold plate dr levers 132 and 134, causing the levers and th 25 respective fold plates 128 and 129 to mo simultaneously. Drive arm 136 is rigidly connec at. one of its ends to the lower end of fold pl drive lever 132, connecting arm 138 is connec atone of its ends to the other end of drive arm 1 30 and crank arm 139 is connected to the other end - connecting arm 138 and to fold plate drive motor 1 Thus, when fold plate drive motor 140 rotates crank arm 139, fold plate drive levers 132 and oscillate as indicated by double-headed arrows 35 and 142 so as to move fold plates 128 and 129 _ indicated by arrows 143 and 144 alternately into and out of the first and second sheet clamp assemblies 1.08 and -109.. The end portions of the- ..fold, plates 128 and 129 are angled at 146 and 147 so that when the 5 fold plates are moved into the clamps 108 and 109, •the angled edge, portions 146. and .147 of each fold plate 128 and 129 will lie parallel to the sheet support platforms 122 and 124. As progressively illustrated in Figs. 10 4A— 4G, the accordion section of the sheet folder 35 - feeds the leading edge portion 22 of the sheet 15 down the inclined guide plate 100 while the friction plate 91 is lifted away from the guide plate, so that the leading edge portion is free to move and is 15 directed toward first clamp assembly 108. A photocell 148 is located adjacent the lower edge of guide plate 100 and detects the oncoming ' leading edge 22 of the sheet 15 as it moves toward first clamp assembly 108. After a short time delay after the 20 detection by the photocell 148 which is sufficient to allow the leading edge portion 22 to reach first clamp assembly 108, the pneumatic cylinders 115 of first clamp assembly 108 are energized to move upper clamp plate 114 down into a holding engagement with 25 the leading edge portion 22 of the sheet (Fig. 4B), and friction plates 91 are allowed to drop against guide plate 100. The first fold plate 128 is thrust into the plane of sheet 15 to pull the sheet between the guide plate 100 and friction plates 91 and to 30 .spread the sheet away from its leading edge portion ... -..22 and- away from first clamp assembly 108 toward second clamp assembly 109 (Fig. 4C). When the first fold plate 128 reaches its distended position, second clamp assembly 109 is retracted by its cylinders 115 35 into its down, grasping position about the sheet 15 __ and the flattened end portion 146 of first fold pla 128 (Fig. 4D).. The first fold plate 128 is th retracted so as to pull out from second cla assembly 109 (Fig. 4E) and move about from benea 5 guide plate 100, and in the meantime, the cylinde 115 of first clamp assembly 108 open the first cla assembly. Second fold plate 129 now moves benea guide plate 100 into the plane of the sheet and 10 into first clamp assembly 108 (Fig. 4F) r spreadi the sheet 15 away from the second clamp assembly 1 into the first clamp assembly 108 and pulling t sheet between guide plate 100 and friction plates 9 When second fold plate 129 has been fully insert 15 into first clamp, assembly 108, first clamp assemb 108 is closed by its cylinders 115 (Fig. 4 downwardly against the sheet 15 and secon fold pla 129, thus holding the sheet in the clamp assembl The second fold plate 129 then retracts from fir 20 clamp assembly 108, leaving the sheet held in fir clamp assembly 108, a.nd moves out from- beneath gui plate 100. The cycle of " operation continu progressively (Figs. 4B — 4G) until the entire leng 25 of sheet 15 has been formed in an accordion fo within the first and second clamp assemblies 108 a 109. As illustrated in Fig. 6, the accordi fold section of the sheet folder 35 includes be 30 conveyors 150 and 151 comprising conveyor tapes 1 and 153 extending across the upper surfaces of she support platforms 122 and 124 and extending abo conveyor rollers 154 and 155 mounted beneath t platforms and driven by a conveyor motor (not shown 35 When the first and second sheet clamp assemblies 1 and 109 have completed their folding functions and have opened, the belt conveyors 150 and 151 are actuated to convey -the- accordion folded sheet 15 along the lengths of its folds and along the clamp assemblies 108 and 109, out to the end of the clamp assemblies and on to the winding-for -assembly 160. ' As illustrated in Figs. 5 and 6, the winding fork assembly comprises an upright support 161 f bearing assembly 162 mounted on support 161, drive sheave 164 mounted on tubular axle 165 on one side of support 161, and axle 1.65 which extends through bearing assembly 162 and which is rigidly connected at its other end to cross bar 166 of winding fork 168. Winding tines 169 and 170 extend parallel to. each other and project horizontally from cross bar 166 and are movably supported on cross bar 166 by clamps 171 and 172. Clamp tines 173 and 174 are located intermediate winding tines 169 and 170 - and also extend approximately parallel to each other and are pivotally supported on cross bar 166 by clamps 176 and 177. Pneumatic cylinder 180 is pivotally mounted on clamp tine 174 and its cylinder rod 181 is pivotally connected to the other clamp tine 173. Thus, when the rod 181 of cylinder 180 is distended, the clamp tines 173 and 174 are pivoted toward engagement with the winding tines 169 and 170, to grasp the accordion folded sheet 15 between one clamp tine and one winding tine. The air supply to cylinder 180 is carried through conduit 182 which communicates with the opening through tubular axle 165 and to" a source of air under pressure (not shown). A circular cam 184 is rigidly mounted on tubular axle 165, and cam switch 185 is located in the plane of the cam. Pneumatic cylinder 186 _ supports cam switch 185 on cylinder rod 188 a bracket 189, so that the cam switch 185 is movab toward and away from the path of cam 184 by cylind 186. 5 A horse* s head support assembly 190 positioned over winding fork 168 and includes stationary support stanchion 191, cross head 1 pivotally supported at one of its ends by stanchi 191, guide bar 194 pivotally mounted at its upper e 10 to the other end of cross head 192 and stationa upright guide sleeve 195 which receives guide b 194. Pneumatic cylinder 198 is mounted on gui sleeve 195 and its rod 199 is connected to cross he 192 and functions to reciprocate cross head 192 15 indicated by arrow 200. Stripping fork 201 is mounted on cross he 192 and includes a bracket 202 sl dable along t length of cross head 192, fork support plate 1 connected to bracket 192 and extending beneath a 20 extending laterally from cross head 192, and tin 205 and 206 mounted at their upper ends in fo support plate 204 and extending downwardly therefro Pneumatic cylinder 208 is mounted on cross head 1 and its rod 209 controls the movement of strippi 25 fork 201 along the length of cross head 192. Lim switch 210 is also mounted on cross head 192 and in the path of movement of stripping fork 201, so to detect the movement of stripping fork 201 at t end of its stroke. A photocell 211 (Fig. 6) 30 located at the end of the accordion folding secti of the sheet folder 35 and detects the oncomi leading end of the accordion folded sheet as t sheet moves into the winding fork assembly 160. When the photocell 211 detects the oncomi 35 leading end of the accordion folded sheet from t 17 accordion folding section of the sheet folder 35, it actuates the clamp cylinder 180 of the winding fork assembly 160 after a time dela su ficient to allow the leading end of the sheet 15 to move between the lower one of the winding tines 169 or 170 and its adjacent clamp -tine ' 173 OF 174. The clamp tines 173 and 174 are then thrust apart toward engagement with the winding tines 169 and 170 by cylinder 18Q, thereby clamping the leading end portion of the sheet 15 between a winding tine and a clamp tine, and the drive motor (not shown) rotates sheave 164 (Fig. 5} and winding fork assembly 160 in the direction indicated by arrow 212 (Fig. 7) so as to wind the sheet in a substantially flat, spiral folded configuration about the winding tines 169 and 170 of the winding fork 168. After a time delay sufficient to move the leading end portion of the sheet into the winding fork, the conveyor belts 150 and 151 of the accordion fold section of the assembly are deactivated, thereby imparting drag to the trailing portion of the sheet 15 which follows the leading portion onto the winding fork, causing the sheet to become tightly wound about the winding tines 169 and 170. Furthermore, a pair of friction plates 214 and 215 are each supported in a cantilever arrangement on support stanchions 216 and 217 on opposite -sides of the winding fork 168, so that the innermost edges of the friction plates 214 and 215 tend to engage the portions of the sheet extending about the winding tines 169 and 170, to further compress the sheet against the windin -tines an -therefore densely pack the sheet on the winding fork assembly. After the sheet has been wound on the winding fork assembly 160, the rotation of the winding fork is terminated with the winding fork "BUREA _0MPI Pty j . " wipo J — . oriented in a horizontal attitude (Fig. 8), and th stripping fork 201 is lowered by the horse's hea support assembly 190 so that the tines 205 and 206 the stripping fork 201 project between the clam tines 173 and 174 and their respective winding tine 169 and 170. When the stripping fork has had enoug time to insert its tines into the winding fork, th cylinder 208 of the stripping fork assembly i actuated to move the stripping fork out through th 10 tines of the winding fork, thus moving the shee - wound on the winding fork off the ends of the tine of the winding fork and onto an awaiting work table etc When the stripping fork 2Q1 engages limi switch 210 f the horse 1 s head support assembly 190 i 5 raised and the stripping fork is moved back to it original position above winding fork assembly 160 Also, cylinder 186 is actuated by limit switch 210 moving cam switch 185 up so that its switch elemen is in the path of the cam 184, and the motor tha 20 drives the winding fork assembly 160 is als energized by limit switch 210. The winding fork 16 therfore begins to rotate away from its horizonta attitude, and when it has rotated 90°, a projectio on cam 184 actuates cam switch 185, terminatin 2 further rotation of the winding fork assembly leaving the winding fork assembly in a vertica orientation (Figs. 5 & 6) , read for receivin another sheet from the accordion folding section o the sheet folder 35. 0 As illustrated in Fig. 9, ' the control o the mechanical infeed elements of the accordio folding section of the sheet folder 35 comprise photocells 39 and 40 which are located at the end o the conveyor and which initiate the feeding of th 5 sheet from the conveyor to the sheet folder 35. Th "BU * 5? _ circuits for photocells 39 and 40 are substantially the same and each includes a positive conductor 220 to which the photocell is connected. Photocell 39 is connected through conductor 221 to biasing resistors 5 222 and 224, with biasing resistor 222 connected to the base of first transisto 225 r and the -output of transistor 225 goes through conductor 226 to the base .of second transistor 228. The output of transistor 228 is connected to capacitor 229 and resistance 230 10 in parallel, and then to diode 231 and to the coil * 232 of relay switch 233. The coil 232 is connected through conductor 234 to positive conductor 220. Conductor 234 also is connected through the contacts 235 of relay 233, and the contacts are connected through conductor 236 to the base of transistor 238. The output from transistor 238 extends to the right through conductor 239 and conductor 240 to air control valve 241 and also in parallel through diode 242 to the positive conductor 220. Air control valve 241 is thus actuated to close the finger clamp of finger clamp assembly 58 (Fig. 2) by charging the cylinder 69 and closing the fingers 65 and 66 about the leading edge portion of the sheet 15. The conductor 239 from the output of transistor 238 also 25 extends through diode 244 and is connected in a holding circuit back through the coil 232 of relay 233. Thus, the output from transistor 238 will be maintained and air control valve 241 will remain in its shifted position without a further signal from 30 photocell 39. The output from transistor 238 also extends through conductor 245 to the left of he diagram. Thus, the circuitry illustrated within the dashed lines 246 comprises the first photocell circuit. A similar second photocell circuit 248 is 35 illustrated inside the dashed lines 248. Thus, both " BUREA _ photocell circuits 246 and 248 are initially actua in response to the photocells 39 and 40 seeing oncoming edge of the sheet 15, and these circuits latched on and provide an output through conduct 5 245 and 248. The signal from conductor 245 is direc to the coil 249 of relay 250 and then thro .conductor 251 to the positive conductor 220. output from conductor 248 is conducted through 10 coil 252 of relay 254 and then through conductor to the positive conductor 220. Thus, both conta 255 and 256 of relays 250 and 254 are closed. T permits a positive signal from conductors 220, 2 258, through contacts 255, conductor 259, conta I '5 - 256 r and then through conductor 260 to the base transistor 261. The output 262 from transistor then passes through normally closed relay conta 264 to arm travel lock-out valve 265 which cuts the air pressure to movable support frame cylinder 20 (Figs. 2 and 3), thus allowing the springs of spr assembly 51 to move the movable support frame 42 a from the conveyor to an intermediate position betw the conveyor and the sheet folder 35. One of the sewing heads 18 or 19 (Fig. 25 of the conveyor has the circuit to its mo connected to conductor 266 (Fig. 9), through on- switch 268, in parallel through capacitor 269 resistance 270, through diode 271, diode 272, to output of transistor 274. A circuit is also m 30 through conductor 275 through the coil 276 of re 278, and through conductor 279 to the posit conductor 220. This closes the contacts 280 of re 278, putting a positive bias on the base transistor 274, causing a signal to be emitted f 35 the output of transistor 274 through conductor 281 i < finger stretch valve 282, arm travel valve 284, the coil of control relay 286, and diode 288. The coil of control relay 286 then- opens the normally closed contacts 264, thus shifting arm travel lock-out valve 265 back to its original position, where air under pressure- can- communicate- in series irst through arm travel lockout valve 265 and then through arm travel valve 284 to movable support frame cylidner 48. The actuation of arm travel valve 284 directs the air to the other side of cylinder 48 causing the movable * support frame to move from its neutral position over the sheet folder. In the meantime P finger stretch valve 282 charges cylinders 61 of finger clamp assemblies 56 and 58, thereby causing the leading edge of the sheet to be stretched as it is moved into the nip roll of a sheet folder. As the movable support frame 42 moves on into the sheet folder, the support frame enages limit switch 89 (Figs. 2, 3 and 9). Switch 89 in its normally closed position is connected to ground through conductor 290 and reset switch 291 and is connected to the emitter of arm travel transistor 274 through conductor 294, Is connected to the emitter of No. 2 finger clamp output transistor 238a through conductors 292 and 295, and is connected to the emitter of No. 1 finger clamp output transistor 238 through conductors 292 and 296. When limit switch 89 is opened, the negative contact to the emitters of transistors 274, 238a and 238 is lost, which results in the signal being lost from each of the three transistors and killing the signal from. photocell circuits 246 and 248 and from the arm travel transistor 274. Thus, arm travel valve 284 shifts back to its original position, causing movable support frame 42 to shift away from the sheet folder _ back to its waiting position adjacent the convey (Figs. 2 & 3), the finger stretch valve 282 shifted so that the finger clamp assemblies 56 and move toward each other, the coil of control relay 2 5 allows its contacts 264 to close which would normal shift arm travel lock-out valve 265 so as to cut o the flow of air to cylinder 48, but the signal to t base of transistor 261 is also lost because of t opening of the contacts 255 and 256 of relays 250 a 10 254 and no signal passes to arm travel lockout val .265. . Thus, air pressure still communicates throu arm travel lock-out valve 265 and arm travel val 284 to move the movable support frame back to i ready position at the conveyor. Also, finger cla 15 valves 241 and 241a in photocell circuits 246 and 2 are shifted so that the grasping fingers 65 and 66 each finger clamp assembly 56 and 5S open and relea the leading edge of the sheet material which is n at the nip roll 70. 20 " When ' limit switch 89 (Fig. 9) is shifted contact from the movable support frame 42, it makes circuit through conductor 298 through the coil 299 relay 300, and then through conductor 301 to t positive conductor 220. This closes the contacts 3 25 of the relay 300 and makes a circuit from positi conductor 220 through conductor 301, relay contac 302, conductor 304, resistor 305 to the base transistor 306. Conductor 298 is also connected the output of transistor 306, so that a circuit 30 made through conductor 308 to air control valve 3 to positive conductor 220 and also in parall through diode 310 to conductor 220. Thus, a holdi circuit is made through conductor 311, conductor 30 contacts 302 and the coil 299 of relay 300, conduct 35 298 through transistor 306, control valve 309 B - _ positive contact 220. Conductor 311 is connected to conductor 350 (Fig. 10) through the contacts 338 of control relay 325, to ground. Thus, when switch 89 is opened from conductor 298 and moved back to 5 conductor 292, the output from transistor 306 will -continue and valve 309 will remai .in its shifted position. Valve 309 causes cylinder 76 of the zero— max transmission 72 to shift, causing an output to be generated from the transmission, thereby causing the nip roll to begin its rotation. Also, valve 309 shifts cylinder 84 so as to raise the sheet feed plate .88 up against the nip roll 70, thereby urging the leading edge of the sheet against the nip roll and causing the sheet to be fed on into the 1 sheet folder. Also, valve 309 actuates friction plate cylinder 94, causing the friction plates 91 to be lifted away from the guide plate 100, and allowing the leading edge of the sheet to move down the guide plate 100 into the first clam assembly 108. 2 When the leading edge of the sheet moves down the sheet guide 100 toward the first clamp assembly 108, it passes photocell 148 (Figs. 2, 3 and 10) and then moves on into the first clamp assembly. The photocell 148 is in a photoelectric cell circuit 25 312 (Fig. 10) which is similar to the photoelectric cell circuits 246 and 248 of Fig. 9, and its latch relay 319 makes a circuit from positive conductor 220 through conductors 315, 316, the contacts 318 of the relay 319, contact 320 to the base of transistor 321. 30 The output of transistor 321 creates a holding circuit back through the coil 314 of relay 319 and also creates a circuit through conductor 322 and the coil 324 of the control relay 325. Also, an on-delay circuit is- made from relay 319 through its conductor 3.5 320, diode 326, in parallel through resistance 328 "BURE U OMPI and capacitor 329, then in parallel through rel coil 330 and variable potentiometer 331, to groun The setting of the variable potentiometer 331 vari the time delay in which the coil 330 of relay 3 closes its contacts 334. When the contacts 334 a closed, the input through conductor 320 to transist 321 is grounded through conductors 335, 336, throu contacts 334 of relay 332, .to ground. Th terminates a signal from transistor 321 and opens circuit made to the coil 324 of control relay 32 ■ In the meantime, the normally open contacts 338 control relay 325 are closed. The closed contacts 338 of the contr relay 325 make a circuit from positive conductor 2 through conductor 339, in pa ' rallel through steppi relay 340 and diode 341, in parallel throu resistance 342 and capacitor 343, and in parall through conductors 344 and 345 and their lim switches 346 and 347. Also, a circuit is made fr positive conductor 220 through conductor 348, t pilot valve 349 of fold plate drive motor 140, conductor 350 to ground through the contacts 338 control relay 325. This causes the fold plates 1 and 129 to begin their .oscillation into and out the first and second clamp assemblies 108 and 1 (Fig. 3). Limit switches 346 and 347 are located the drive shaft of the fold plate drive motor 140, that limit switch 346 closes momentarily when t second fold plate 129 is received in the first cla assembly 108 and limit switch 347 is momentari closed when first fold plate 128 is received . second clamp assembly 109. When limit switch 346 is closed, a circu is made through the coil of stepping relay 340. Th causes the movable arm 351 of stepping relay to mo ' B _ ,- _ one position to the next contact. When limit switch 346 is opened and limit switch 347 is closed, another circuit is made to the coil of the- stepping relay 340, so as to move the movable arm 351 to the next 5 position. - - When movable arm- 351 is in contact with the number one conductor, a circuit is made from the positive conductor 220 through conductor 352, pilot valve 354, conductor 355, through the first position 10 conductor, through the movable arm 351, to ground. " Pilot valve 354 actuates the several cylinders 115 on the first clamp assembly 108, causing the first clamp assembly to close. When the first limit switch 346 opens and the second limit switch 347 closes, the 15 stepping relay will move its arm 351 to the next position at contact number two, whereupon a circuit is made from positive conductor 320 through conductor 356, pilot valve 358, conductor 359 to the second position conductor through the movable arm 351 to 20 ground. Pilot valve 358 thus causes its cylinders 115 of the second clamp assembly 109 to close the second clamp assembly. In the meantime, since the circuit has been opened to the first pilot valve 354, the irst clamp assembly will have opened. 25 The continued alternate closing of the limit switches 346 and 347 causes the movable arm 351 of the stepping relay to continue to move across its contacts and alternately close each of the clamp assemblies until the stepping switch arm 351 reaches 30 the contact of the switch which is made with the count arm 360,- whereupon -a circuit is made from the positive conductor 220 through conductor 361, through the reset coil of the reset relay 362, through conductor 364, count arm 360, through the lattice of 35 conductors to the movable arm 351, to ground. whereupon the movable arm 351 is set back to its ze position. This terminates the procedure, o alternately clamping the opposite sides of th accordion folded sheet. When the stepping switch arm 35 momentarily made a circuit with the coil of the rese relay 362, a circuit is also made through conducto 365 to transistor 366, the output of which i connected to transistor 368, and transistors 36 provides an output through conductor 370 throug normally-closed relay contact 440, through conducto 371 and through conveyor belt pilot valve 372. Thi causes the conveyor belts 151 and 152 (Fig. 6) t begin their operation to " move the accordion folde sheet toward the winding forl? 168. In the meantime a circuit is made from transistor 368 throug conductors 370 and 374 through the coil 375 of rela 376, through conductor 378 to positive conductor 220 causing the contacts 379 of the relay 376 to close This applies a ground to the conductor 320 leading transistor 321, thereby terminating the signa through control relay 325 and opening the contact 338 of the relay. The opening of the contacts o relay 325 therefore opens the entire circuit of th stepping relay 340 to prevent the stepping relay ar 351 from resuming its movements until the photocel 148 detects another oncoming sheet. When the sheet has been accordion or plea folded, the belt conveyors 151 and 152 move the shee along the length of the accordion folding devic toward the winding fork assembly 160 (Fig. 6), an photocell 211 detects the oncoming leading edge o the accordion folded sheet. As illustrated in Fig 11, photocell 211 makes a circuit from positiv conductor 220 through conductors 401 and 402 t biasing resistors 404 and 405, to the base of transistor 406. The output from transistor 406 is connected through conductor 408 to the base of transistor 409, and the output of transistor 409 is connected through conductor 410 and a diode 411 to the coil 412 of latch relay 414 then back through, conductors 415 and 401 to positive 220. This closes the contacts 416 of relay 414, making a circuit from positive conductor 220, conductors 401, 415, contacts 416, conductor 418, resistor 41.9, to the base of transistor 420. The signal from transistor 420 is conducted through conductor 421 to the coil 412 of relay 414 to form a holding circuit. Thus, the circuitry within the dash lines 422 functions as a - third photoelectric cell circuit, similar to those circuits indicated at 246 and 248 of Fig. 9. Conductor 422 receives the signal from conductor 418, the signal passes through diode 424, in parallel through capacitor 425 and resistance 426, through conductor 428, the signal s then split and passes in series through resistance 429 and variable resistance 430 . to ground, and the other part of the signal passes through the coil 431 of delay-on relay 432 to ground. This circuit is a time delay circuit, and the delay is controlled by the variable resistance 430. After the desired delay has occurred, the coil 431 closes the contacts 434 of relay 432, causing the ground circuit to be made through conductors 436 and 438 to conductor 418, between the resistance 419 and transistor 420. This eliminates the signal the base of transistor 420. Thus, while the photocell circuit 422 initially provides an output through conductor 439 to the coil of conveyor belt relay 440 and the coil of wind-up clutch solenoid 441, the delay-on circuit eliminates _ the signal after the desired time delay, stopping th conveyor belt and making the wind-up clutch. Thus the oncoming leading edge of the sheet has been see by the photocell and the conveyor continues t 5 operate .for a predetermined time delay so that th oncoming end of the sheet is moved into the windin fork, whereupon the conveyor action is terminated an the wind-up clutch is made. After the wind-up clutch has been made, th 10 winding fork beings its rotation and its cam (8 • (Fig. 5) and closes cam switch 445 for each one-hal rotation of the winding fork. The repeated closin of cam switch 445 makes and breaks a circuit fro positive conductor 220, through conductor 446 15 stepping coil 448 r in parallel through resistor- 44 and capacitor 450, and through conductor 451. Th stepping coil 448 of the stepping relay is connecte 'to the movable arm 452 and intermittently shifts th arm 452 across the contacts 454 of the stepping rela 20 in response to each closing of cam swi ch 445. Whe the stepping arm 452 is aligned with indicator ar 455, a circuit is made from ground through conducto 456, then in parallel through resistance 458 an capacitor 459, through the coil 460 of stop rela 25 461, and through conductor 462 to the positiv conductor 220. Relay coil 460 then closes contact 464 and a signal is made through stepping switc contact 455, conductor 466, conductor 465, rela contacts 464, conductor 456, diode 468, to conducto 30 418, thus grounding the signal made to transisto 420. Transistor 420 thereby loses its output throug ' UR O .A,- WI __ conductor 439, so that the valve 441 of the wind-up clutch is opened so that the wind-up clutch no longer drives the winding- fork, and the coil 440 of the relay switch to the conveyor drive system would 5 ordinarily permit the conveyor to resume its •function.- Cam- switch .4.45, having been opened on every 180° rotation of the windin fork, causes the winding fork to be stopped in a horizontal attitude. The ground signal from stepping switch 10 452—455 also is transmitted through conductor 456 through diode 470, the coil 471 of latch relay 472, through conductor 474 to positive conductor 220. This causes the contacts 475 of relay 471 to close, .sending a positive signal through conductor 474, 15 contacts 475, conductor 476, -resistance 478 to the base of transistor 479. The output of transistor 479 sends a signal to conductor 480 which forms a holding circuit through coil 471 of latch relay 427 and which also sends a signal, to conductors 481, 482, 484 and 20 485, thrcugh diode 486, reset coll 488 of stepping relay 452 — -455, valve 489 which operates cylinder 19& of stripping fork 201 (Fig. 5) and valve 490 which operates cylinder 208 of stripping fork 201. The reset coil 488 of the stepping relay shifts the 25 movable arm 452 back to its zero position and breaks the circuit made from the stepping relay. Also, valve 489 causes the stripping fork 201 to move, down into the winding fork while valve 490, after a pneumatic time delay, causes cylinder 208 to pull the 30 stripping fork 201 through the winding fork and to - strip the sheet from the winding fork. When the stripping fork reaches the end of its stroke, it engages the limit switch 210 (Figs. 5, 8 and 11) , shifting the switch away from conductor 35 491 over to conductor 492. Since conductor 491 connects the ground to the emitter of transistor 480, 'BURE °MPI_ A- WIPO ^NATiCS the signal from transistor 480 is lost, whi deactivates the reset coil 488, valve 489 wh activates the cylinder 198 that pulls the stripp fork down, thereby causing the stripping fork to raised, and deactivates valve 490 which causes stripping fork to be moved through the winding fo thereby urging the stripping fork back to its re position. When limit switch 210 makes contact w ° conductor 492, a circuit is made from ground thro conductor 492 through latch relay 414, conductors and 401 to positive conductor 220, causing contacts 416 of the relay 414 to be closed aga This causes transistor 420 to send an output sig 5 through conductor 439 to the valve 441 of the wind clutch of the winding fork, causing the winding f to begin rotation again. However, when the valve was shifted by the shifting of limit switch 210 raise the stripping fork, valve 489 also actua 0 switch cylinder 186 (Fig. 5) to lift switch 185 toward the path of the cam 184 of the winding fo When the winding fork rotates approximately 90°, cam will close switch 185, which, in series w closed switch 442, grounds the signal to transis 420, therefore terminating the signal to wind- clutch valve 441 and terminating the rotation of wind-up fork. This leaves the wind-up fork i vertical attitude, ready for receiving anot accordion folded sheet in the manner illustrated 0 Fig. 6. While this invention has been described detail with particular reference to a prefer embodiment thereof, it will be understood t variations and modifications can be effected wit 5 the spirit and scope of the invention as descri hereinbefore and as defined in the appended claims

Claims: AMENDED CLAIMS (received by the International Bureau on 24 March 1980 (24.03.80)) 1. A method of folding rectangular b sheets and the like comprising moving a sheet in substantially unfolded configuration along its leng along a horizontal path, grasping the sheet at t sides of its leading edge, pulling the sheet at i leading edge across its length to stretch the leadi edge of the sheet, moving the stretched leading ed - of the sheet into a nip roll means for grasping t leading edge portion of the sheet, and feeding t leading edge of the sheet with the nip roll mea down an incline toward a first clamp means, and wh the leading edge of the sheet arrives at the fir clamp means, releasing the sheet with the nip ro means and holding the leading edge of the sheet the first clamp means, spreading the sheet away fr the first clamp means into a second clamp mean holding the sheet in the second clamp means a releasing the sheet with the first clamp mean spreading the sheet away from the second clamp mea into the first clamp means, repeating the steps holding, spreading and releasing until the sheet formed in a flat elongated accordion fold, moving t accordion folded sheet laterally along its fold length and progressively folding the sheet across i accordion folds in an approximately flat spiral fol 2. The method of Claim 1 and wherein the steps of alternately spreading the sheet away from the first and second clamp means comprises thrusting a first plate into the sheet and into the second clamp means from a position adjacent the first clamp means and withdrawing the first plate from the second . clamp means, and thrusting a second plate into the sheet and into the first clamp means from a position adjacent the second clamp means and withdrawing the 10 second plate from the first clamp means, and wherein the steps of holding the sheet in the first and second clamp means comprises holding the sheet with the first or second clamp means as the second or first plate withdraws from the first or second clamp 15 means respectively. 3 . Th e method o f Cl a im 1 and f ur ther including the step of applying drag friction to the sheet as the sheet moves into its accord ion folded 20 configuration . 4 . Th e method of Cl aim 1 and f urther including the step of accumulating a loose length of the sheet between the steps of grasping the sheet and * "- - ~ , moving the lead ing edge of the sheet into a nip roll means . __ • 5. A method of feeding a rectangular b sheet or the like from a conveyor line or the like a nip roll or the like comprising grasping the she adjacent its leading edge at its side edges, pulli 5 the sheet at its grasped areas to apply tension the leading edge portion of the sheet, and while t sheet has tension applied to its leading ed portion, moving the leading edge portion into a n roll assembly and rotating the nip roll to move t 10 sheet through the nip roll assembly. 6. A method of folding sheet materi comprising moving one edge portion of the sheet in a first clamp, holding the edge portion in the she 15 in the first clamp, spreading the sheet away from t first clamp into a second clamp, holding the she with the second clamp and releasing the sheet wi the first clamp, spreading the sheet away from t second clamp into the first clamp, holding, the she 20 with the first clamp and. releasing the sheet with t second clamp, and repeating the holding, spreadi and releasing steps until the sheet is formed in flat accordion folded configuration- 25 7. The method of Claim 6 and furth including the step of applying drag to the she during the spreading steps. " BU _O ^T, WI ?N _ 8. The method of Claim 6 and further - including the steps of moving the sheet in its accordion folded configuration along the lengths of its folds and winding the sheet into an approximately 5 flat spiral folded configuration. 9. The method of Claim 6 and wherein the steps of spreading the sheet into the second clamp comprises thrusting a first fold plate from adjacent 10 the first clam into the plane of tbα sheet and into • the second clamp, and wherein the step of spreading the sheet into the first clamp comprises thrusting a second fold plate from adjacen the second clamp into the plane of the sheet and into the first clamp. 15 . " BURE _OMPI v ~wipo~ *NATlO _ 10. A method of folding a bed sheet or t like comprising moving an unfolded sheet along i length in a downward direction from above a first a a second clamp means until the leading edge of t 5 sheet moves into the first clamp means, holding t leading edge of the sheet in the first clamp mean moving a first fold element from above the fir clamp means laterally into the plane of the sheet a into the second clamp means, holding the sheet in t 10 second clamp means and releasing the sheet with t - first clamp means, withdrawing the first fold eleme from the second clamp means, moving a second fo element from above the second clamp means lateral into the plane of the sheet and into the irst cla 15 means, holding the sheet in the first clamp means a releasing the sheet with the second clamp mean withdrawing the second fold element from the fir clamp means, and repeating the movements of the fo elements and holding and releasing of the sheet unt 20 the sheet is formed in an accordion fold configuration. 11. The method of Claim 10 and wherein t steps of moving one fold element into the sheet a 25 withdrawing the other fold element from a clamp mea are performed substantially simultaneously. - 12. the method of Claim 10 and wherein t steps of initiating the holding the sheet with o 30 clamp means and releasing the sheet with the oth clamp means are performed substantial simultaneously. 13. The method of Claim 10 and further including the steps of moving the sheet in its accordion folded configuration along the lengths of its folds, and winding the sheet into an approximately flat spiral folded configuration. 14. A method of folding a bed sheet or the like from an accordion configuration to an approximately flat spiral configuration comprising the steps of moving the accordion folded sheet along the lengths of its folds, grasping the sheet behind its leading end between the tines of a multiple tine winding fork, rotating the fork so that its tines move in concentric circular paths and the sheet winds about the tines of the fork. * 15. The method of Claim 14 and further including stopping the rotation of the winding fork with the tines of the fork oriented horizontally, and pulling the folded sheet off the ends of the tines of the fork. 16. The method of Claim 14 and further including the steps of applying friction to the sheet as it is being wound onto the winding fork to pull the sheet tightly about the winding fork. __ 17. Apparatus for folding bed sheets a the like in an accordion folded config rati comprising first and second elongated cla assemblies in parallel spaced apart faci 5 relationship, guide means above and between sa clamp assemblies for guiding a sheet from above t clamp assemblies downwardly into said first cla assembly, a first folding plate positioned above sa first clamp assembly, a second folding pla 10 positioned above said second clamp assembly, mea for moving said first folding plate beneath sa guide means and into said second clamp assembly whi withdrawing said second folding plate from said fir clamp assembly and for moving said second foldi 15 plate beneath said guide means and into said fir clamp assembly while withdrawing said first foldi plate from said second clamp assembly, 18. The apparatus of Claim 17 and furth 20 including means for applying friction substantial uniformly across the width of the sheet as the she is drawn into said first and second clamp assemblie 25 19. The apparatus of Claim 17 and where said guide means comprises a downwardly inclin guide plate including horizontal upper and low edges, a rotatable nip roll positioned above a rotatable about an axis parallel to the upper edge 30 said inclined guide plate, and means for urging she material into contact with said nip roll, whereby t nip roll moves sheet material down the inclined gui plate to the first clamp assembly. 35 _ 20. The apparatus of Claim 19 and further including a plurality of friction plates positioned over said guide plate, and means, for raising and lowering said friction plates away from and toward 5 frictional contact with the sheet as the sheet moves . .down said, guide -plate. 21. The apparatus of Claim 17 and further including conveyor means positioned between said 10 first and second clamp assemblies for moving the sheets folded in said clamp assemblies along the lengths of and out of said first and second clamp assemblies. 15 22. the apparatus -of Claim 17 and further including a winding fork positioned at one end of said first and second clamp assemblies, means for moving a sheet folded in said first and second clamp assemblies into said winding fork, motor means for 20 rotating said winding fork, whereby the folded sheet is wound about the winding fork. 'BU EA _0MPI ^NATIO 23. Apparatus for transferring a bed she or the like in an unfolded configuration from conveyor to a folder comprising a support assembly, pair of clamp assemblies mounted on said suppo assembly in spaced relationship with respect to ea other and in alignment with the opposite side ed portions of a sheet on the conveyor, detection mea at the end of said conveyor for each of said cla assemblies in alignment with the opposite side ed portions of the sheet on the conveyor, clamp closi means for closing each of said clamps in response the detection of the leading edge portion of oncoming sheet by said detection means, and means f moving said clamp assemblies away from each other. 24c The apparatus of Claim 23 and furth including means for first moving said support memb away from the conveyor, and after a time delay f moving said support member further toward the folde 25. Apparatus for folding bed sheets and the like comprising a nip roll, means for moving an edg of a sheet into contact with said nip roll, a downwardly inclined guide plate ex tend ing away from said nip roll for guid ing a sheet downwardly away " from the nip roll, a first elongated clamp assembly in alignment with said guide plate for receiving the R ead ing edge of the sh e e t m a t e ri a l , a second elongated clamp assembly parallel to and facing said first clamp assembly, a first fold plate positioned • above said ' first clamp assembly and movable beneath said guide plate into and out of said second clamp assembly, a second fold plate positioned above said second clamp assembly and movable beneath said guide plate into and out of said first clamp assembly, and means for alternately closing said first and second clamp assemblies about the second and f irst fold plates respectively to hold the sheet in the clamp assemblies. 26. The apparatus of. Claim 25 and further including conveyor means for moving a sheet folded in said first and second clamp assemblies along the length of said " first- and second clamp assemblies. 27. The apparatus of Claim 25 and further including means for bearing against the sheet as the sheet moves down said guide plate for applying drag friction to the sheet. 28. The apparatus of Claim 25 and furth including a winding fork positioned at one end said first and second clamp assemblies, means f rotating said winding fork, and means for moving t folded sheet along the length of said first a second clamp assemblies into said winding for whereby the sheet is wound about the winding fork an approximately flat spiral fold. 29. A winding assembly for folding a she or the like comprising a winding fork including least two approximately parallel tines, means f rotating said winding fork so that its tines move concentric circles, clamp means for clamping t leading end portion of a sheet to one of said tine whereby when said winding fork is rotated the she becomes wound about said tines. 30. The apparatus of Claim 29 and furth including a stripping fork assembly comprising support shaft extending approximately parallel to t tines of said winding fork and movable toward a away from said winding fork, a stripping fork mount on and movable along said support shaft, means f moving said support shaft toward and away from sa winding fork and means for moving said stripping fo along the length of said support shaft, sa stripping fork including tines movable between t tines of said winding fork, whereby the strippi fork moves down into said winding fork and then alo the length of said winding fork to remove the she wound on said winding fork off said winding fork.

Inventors: BROCKLEHURST C
Applicants: OPELIKA MFG CORP
Application year: 1979
Main classification: B65H45
IPC codes: B65H45