Patent GB-635266-A (GB)
Title: Improvements in and relating to automatic folders
IPC: D06F89/00
Filed: 1946-12-06
Abstract: 635,266. Folding sheet material. ABELL, H. DE F., and ABELL, H. E. Dec. 6, 1946, No. 36132. [Class 42 (ii)] A machine for folding a piece of material at its mid-point comprises an arm pivoted for rotation, a constantly-rotating member having a friction surface adjacent thereto, with a friction pad on the arm contacting.the said surface, a ratchet-wheel constantly rotating at twice the speed of the member, a folding blade actuable by passage of the arm past a tripping point, means actuable by passage of the leading edge of the material past a second tripping point to release the arm for rotation with the said member, and actuable by passage of the trailing edge of the material past the said second tripping point for coupling the pawl on the arm to the ratchetwheel. The machine comprises upper front and rear sections, 24, 26, each having a fold-forming mechanism, and a base-section 22. The front section 24 has carrier tapes 74 running over rollers on shafts 70, 48, 50, 52, 54, 56, 58 and 60, and tapes 86 running over rollers on shafts 48, 50, 52, 54, 56, 80 and 82 and contacting the tapes 74 over a portion of .their path. The rear section 26 has tapes 102 running over rollers on shafts 90, 92, 94, 96 and 98, tapes 118 running over rollers on shafts 106, 92, 94, 96, 110, 114, 112 and 108, and contacting the tapes 102 oyer a portion of their paths, and the tapes 126, running over rollers on shafts 122 and 114, at a point near the shaft 114. The base-section has tapes 36 running on rollers on shafts 30 and 32, and, spaced above the tapes 36, tapes 44 running on rollers on shafts 38, 40. The tapes are all driven from the ironer with which the folding-machine is associated, by means of chain-and-sprocket drives. Each upper section has a fold-forming mechanism comprising a frame composed of a number of fingers 146 (Fig. 3) extending between the carrier tapes, and secured to angle-irons 134 from which extend four bars 132 which are guided by rollers on brackets on the fixed angle irons 128, 136. The two inner bars 132 are connected by a bar 148 to which is attached one end of an operating cable 152, the other end passing into a control unit 154. The folding frame is loaded by a spring 172. When the folding mechanism associated with the section 24 is operated, it functions to form a fold in an article emerging from between the tapes 74 and 86 and to present it to the bite between the tapes 102 and 118 of the section 26. When the folding mechanism in the latter section is operated, a second fold is formed in an article emerging from between the tapes 102 and 118, and presented to the bite of the tapes 118 and 126. The articles finally fall on the tapes 44 or 36 and are removed thereby. The control mechanism 154 comprises a housing 158 in which are journalled shafts 178 and 180, which are geared together through gears 182, 186 and 184. The cable 152 is connected to an idler disc 192, loosely-mounted on the shaft 178. A ratchet-wheel 202 is fast on the shaft 178; the idler disc 192 may be connected to the ratchet-wheel 202 through a pawl 198 when the latter is actuated. On the shaft 180 is keyed a ratchet-wheel 204 which is also provided with a bevel-gear 206; a corresponding fixed bevelgear 208 is' provided opposite this on the casing, and between these is a disc-member 210, loose upon the shaft 180, which carries a pinion 214 meshing with both bevel gears 206 and 208. Thus the disc 210 is driven at half the speed of the ratchet-wheel 204. The disc 210 has a marginal flange 212 which is in the same plane as the ratchet-wheel 204. Two or more arms 220 are loosely-mounted on the shaft 180, and each carries a pivoted lever 224, one arm of which is pressed, so as to urge the pawl which it carries towards the ratchet-wheel 204, by a spring, the other end of which bears against a friction pad 228, also mounted on the arm 220, and presses it against the rim of the flange 212. A member 234, having a flange extending for three-quarters of its circumference, the remainder being cut away, is loosely-mounted on the shaft 180 and is positioned by guide-pins fastened to the wall 160; it is pressed against the balls 238, located in gaps in the spacer disc 232, by a spring 236. A fixed member 244 having a flange which corresponds to the cutaway sector of the disc 234, is secured to the wall 160. A lug on the disc 232 protrudes through the wall 160 and is connected by a cable 266 to a lever 268 in the folding-machine, which is adapted to be tripped by the leading edge of the article to be folded, thus rotating the disc 232 and dislodging the balls 238 from their seatings 240. This moves the disc 234 axially against the spring 236 and brings it into the same plane as the member 244. At the same time the escapement 252 is caused to rotate about its pivot on the member 244, releasing the foremost arm 220, which is carried round with the disc 210, and retaining the remainder. The flange on the disc 234, acting on the tail of the lever 224 on the arm 220 prevents the pawl thereof from engaging the ratchet teeth of the wheel 204 until the end of the article rides off the lever 268, when the flanged disc 234 is retracted; after this the arm 220 is carried round with the ratchet-wheel 204 until disengaged therefrom by the tail of the lever 224 contacting the flange of the fixed member 244. As the arm 220 passes the pawl 198 on the idler disc 192, it contacts the spring 316 thereon and causes the pawl 198 to engage the ratchet teeth of the rotating wheel 202. The idler disc is then carried round with the latter until the pawl 198 is disengaged by its leading end contacting the pin 318. The cable 152, being attached to the idler 192, is thus caused to operate the folder.