Patent GB-1358344-A (GB)
Title: Machine for turning-in the edge of a piece of flexible sheet materi al especially a textile fabric
IPC: A41H25/00
Filed: 1972-03-20
Abstract: 1358344 Folding edges of sheet material CENTRE D'ETUDES TECHNIQUES DES INDUSTRIES DE L'HABILLEMENT 20 March 1972 [19 March 1971 18 Nov 1971] 12943/72 Heading B5K  An edge of an opening 265, Fig. 35, of a sheet 266 is folded by positioning the sheet with the edge to be folded projecting beyond the border of an opening in the plate, folding the sheet edge at a right angle by movement of a device at right angles to the plate, turning-back the alreadyfolded edge to lie against the plate by movement of a device parallel to the plate, the latter device comprising a plurality of laterally movable members, and displacing the plate in its own plane to free the folded edge. The edge may be a portion of the border of the sheet, either curvilinear, Fig. 37 (not shown), or rectilinear, Figs. 38 and 39 (both not shown), or may be a portion or the complete periphery of an opening formed in the sheet, Figs. 34-36. The invention is applicable to forming the rectangular opening of a trousers pocket or to forming buttonholes. The sheet may be a textile fabric, e.g. woven, non-woven or of mesh type, or a thermoplastic sheet. In one embodiment, Fig. 1, the machine comprises a frame 6 in which the sheet to be folded is located, an insetting and folding-back assembly 11, a heat plate assembly 12, a wedge 13 for actuating the assembly 11 and a set of sliding plates 14 to support the sheet at least along the edge portion of an opening to be folded. The frame 6 comprises rectangular metal plates 21, 22 pivoted about a pin 23, having a rectangular opening 24, Fig. 2, and liftable at 25, 26. The frame 6 is lockable in a desired position on columns 2, 3, 4 by conical studs 32, 33 on an arm 31 engaging in orifices in the columns 2, 3. The assembly 11, Figs. 4 and 6, comprises a rectangular plate 46 corresponding to the dimensions of the opening in the sheet and fixed to a rod 47 slidable in a fixed guide 48 and positioned angularly by rods 51, 52. L-section pallets 56, 57 are hinged at 55 to plates 53, 54 fixed to the ends of the plate 46 and are urged by springs, e.g. 58, to the position of Fig. 6. Stops 63, 64 limit the pivotal movement of the pallets 56, 57. Smaller pallets 67, 68 are hinged on pins 71, 72 carried by plates 73, 74 fixed to the plate 46 and are provided with extensions 75, 76 acted on by restoring springs 77, 78, stops 81, 82 limiting this movement. The assembly 11 is urged upwardly by a spring 86 and is movable downwardly by a cam 96, fixed to a drivable shaft 103, through a follower 17 on an arm 98 fixed to an arm 99 carrying a roller 101 acting on the rod 47.  The assembly 12, Fig. 10, comprises an electrical resistance wire 121 between plates 122, 123 fixed to four columns 124 secured by insulating bushes 126 to an apertured plate 127 mounted on rods 128 slidable in the guide 48. The assembly 12 is urged upwardly by springs 131 and is provided with heat storage means comprising two parallelepipedal blocks 136, 137. Downward movement of the assembly 12 is effected by a cam 145, Fig. 1, on the shaft 103 through an arm 146 fixed to arms 147, 148, Fig. 2, carrying rollers (149), (150), Fig. 3 (not shown), acting on the rods 128. The wedge 13, Fig. 18, comprises a bar 161 which is tapered to a rib 162 having inclined end faces 163, 164 and is mounted on a rod 168 slidable in a fixed guide 169 and positioned angularly by rods 171. Upward movement of the wedge 13 against the action of a spring (172), Fig. 20 (not shown), is effected by a cam 182 on the shaft 103 through a follower 183, Fig. 1, on an arm 184 fixed to an arm 186 carrying a roller 187 acting on the rod 168. The set of plates 14, Figs 15 and 17, comprises a plate 192 fixed on rods 193 slidable in the guide 169 and urged downwardly by springs 194. The rod 168 carrying the wedge 13 passes through an opening 201 in the plate 192. Plates 205, 206 are secured to the plate 192 and have secured thereto a plate 216 on which are slidably mounted two plates 217, 218 movable by jacks 212, 213. A hollowed-out portion 238 is provided in each of the plates 217, 218 to accommodate a thermo-activatable adhesive for securing the folded edge. Upward movement of the plate 14 is effected by a cam 241, Figs. 1 and 2, on the shaft 103 through a follower 242 carried by an arm 243 fixed to arms 244, 245 carrying rollers (246), (247), Fig. 3 (not shown), acting on the rods 193. The above-described machine is used to fold and secure four edges 261, 262, 263, 264, Fig. 35, of a rectangular opening 265 formed in a sheet 266 by a double-Y incision 267, Fig. 34. In operation, a thermo-activatable adhesive piece 268 is placed in the portions 238 and the frame 6 is opened whilst the sheet 266 is inserted. The assemblies 11, 12 are moved downwardly with the assembly 12 at its operating temperature and the wedge 13 and the set 14 are moved upwardly. The pallets 56, 57 move downwardly on to the edges to be folded, Fig, 21 (not shown), and fold these edges downwardly through a right angle, Fig. 22 (not shown). The rib 162 of the wedge 13 engages between the pallets 56, 57 to displace them outwardly and cause them to fold the sheet edges against the plates 217, 218, Fig. 23 (not shown). The jacks 212, 213 move the plates 217, 218 away from each other and the wedge 13 moves upwards over a distance corresponding to the thickness of the plates 217, 218 to flatten the folded edges against the adhesive piece 268, Fig. 24 (not shown). Heat supplied by the plate 12 ensures melting of the adhesive so that the folded edges are secured. The wedge 13 and the set 14 move downwardly and the assemblies 11, 12 move upwardly. The frame 6 is released by actuation of the jack 37 and the edge-folded sheet is removed. In a modification, the opening in the sheet has a curvilinear configuration, Fig. 36 (not shown). In another embodiment, Figs. 26 and 27, the insetting device comprises a punch 301 and the folding-back device is a separate punch 302. The punch 302 comprises four members 304, 305, 306, 307 which can be applied against each other to form a rectangular section block but are capable of withdrawing from each other to effect folding. The webs 304, 305 are supported by slidable screws 315, 315A and are urged together by springs 321, 321A. Screws 322, 323 and 322, 323A maintain the members 304, 305, respectively, in horizontal positions. The members 306, 307 are supported by slidable screws 327, 327A, urged towards each other by springs 330, 330A and maintained horizontal by screws 331, 331A. The members 304, 305 and 306, 307 are separable by cams 334, 335, respectively, on a shaft 336. Tubular guides 341, 342 slide along rods 343, 344 secured to a fixed plate 345. Downward movement of the punch 302, against the action of a spring 347, is effected by a cam 351 acting on a cross-piece 348 secured to the guides 341, 342. In operation, the sheet and the adhesive are positioned in the frame 6 and the punch 301 is lowered to fold the sheet edges downwardly through a right angle and contacts the punch 302, Fig. 30 (not shown). The punches 301, 302 move upwardly until the top face of the punch 302 is exactly level with the plates 217, 218, Fig. 31 (not shown). The members 304, 305, 306, 307 move away from each other and fold the sheet edges against the plates 217, 218, Fig. 32 (not shown). The plates 217, 218 slide away from each other and the punches 301, 302 move upwardly over a distance corresponding to the thickness of the plates 217, 218, Fig. 33 (not shown). Securing of the folded edges is effected by heat and pressure. In a further embodiment, Figs. 40, 43 and 44, cutting of the opening in the sheet is effected at the start of the folding cycle. The punch 301 of Figs. 26 and 27 is replaced by a punch 401 containing a knife assembly 402. The punch 401 comprises four members 405, 406, 407, 408 supported by a plate 418 fixed on rods 421, 422 slidable in a vertical guide. The assembly 402 comprises a knife 441 mounted on a strip 442 fixed to a rod 443 slidable in the vertical guide. The knife 441 is shaped as shown in Fig. 44 to form a double-Y cut 267, Fig. 34. In operation, the sheet is positioned in the machine with the punch 302 lying in the same plane as the plates 217, 218, Fig. 47 (not shown). The punch 401 and the assembly 12 are lowered until the punch 401 abuts the punch 302, Fig. 48 (not shown). The knife 441 moves downwardly to form the cut in the sheet and then moves upwardly whilst the punches 401, 302 move downwardly to fold the cut sheet edges through a right angle, Fig. 49 (not shown). The punches 401, 302 move upwardly until the contacting faces thereof are located slightly beneath the undersurface of the plates 217, 218, Fig. 50 (not shown). The individual members of the punch 302 move away from each other to press the sheet edges against the plates 217, 218, Fig. 51 (not shown). The plates 217, 218 withdraw and securing of the folded edges is effected.