Patent GB-654177-A (GB)
Title: Improvements in or relating to machines adapted for inserting eyelets into workpieces
IPC: A43D100/02
Filed: 1947-12-27
Abstract: 654,177. Eyeleting. BRITISH UNITED SHOE MACHINERY CO., Ltd., HAZELTON, G., BARKER, W. A., and GIBSON, G. W. Dec. 27, 1947, No. 34304. [Class 43] A power-operated machine for inserting barrelled fasteners. e.g. eyelets or lacing hooks, into workpieces includes opposed punching members and opposed clenching members, said four members forming part of an assembly swingable from a punching position to a clenching position, the work being held from displacement during said swing- ing. In one form each punching member is operated by a lever which is pivoted on a carrier and is operated by a link, the two links constituting a toggle. In another form both punching members, after operation, are moved away from the work. In another form at least one punching member is movable along a rectilinear path, the assembly being swingable about an axis parallel to said path. Initially an anvil 11 and punch 13 are aligned with a hole in the fixed work-table 27. Depression of a treadle first causes downward movement of the punch 13, and then, the work having been correctly positioned, further depression of the treadle trips clutch mechanism so that a main shaft 35 is rotated through one revolution only. During this revolution a foot 25 is lowered to grip the work, the tools 11, 13 co-operate to punch a hole, the anvil 11 moving up through the hole in the table 27, these tools then separate before being displaced transversely to bring two clenching dies 15, 17 into position ; when the punch 13 first moved down a pin 19, mounted in the clenching die 17, entered the endmost eyelet in a raceway 21, which now moves clear to allow insertion and clenching of the eyelet by the dies 15, 17. After this the parts re-set themselves and the machine comes to) rest. The presser foot 25, Fig. 1 is attached to a rod 37, slidable in the machine frame and urged down by a spring 29, its movement being limited by the engagement of a pin 43 with one arm 45 of a bell-crank lever pivoted to the frame; the other arm 47 is connected by a horizontal rod 51 to one arm 53 of another bell-crank lever, the other arm 55 of which is normally held by the spring 29 in contact with a roll 59 carried by a cam 61 on the shaft 35, so that rotation of the latter results in movement of the roll 59 out of and later into engagement with the arm 55, and hence in lowering and raising of the presser foot 25. The punch and dies are carried in a carrier 65 which can pivot about a vertical axis on studs 67, 69, and which comprises a rearward arm 75 together with upper and lower forward arms 71, 73, the latter arms carrying the punch 13 and die 17, and the anvil 11 and die 15 respectively; The punch and anvil, Fig. 4, are each mounted on plungers movable in vertical bores, the forward ends 79, 87 of two levers pivoted to the! carrier at 83, 91, governing their motion; the rearward ends 81, 89 of these levers form pivots for two toggle links 93, 95, the other ends of which are pivoted on an upwardly extending arm 99 of a lever pivoted on a transverse shaft 103 fixed to the machine frame. A rearwardly extending arm 101 of the last-mentioned lever carries a roll 111 normally held against a cam surface 113 of a cam 115 on the shaft 35 by a spring 107. When the shaft 35 rotates, the cam surface 113 pushes down the roll 111, so that the toggle is straightened and a hole is punched in the work, the arrangement being such that the punch moves further than the' anvil, and that most of the reaction to the punching is transmitted to the bearings 83, 91; when the cam surface allows the roll to rise again the toggle is broken by the spring 107 acting on a depending extension 105 from the lever 99-101, separation of the tools being ensured by a spring (not shown), tensioned across the rear of the arms 81, 89. Swing- ing of the carrier 65, Fig. 1, about its pivots is controlled by a roll 117, which is mounted, with its axis vertical, on the rearward arm 75 of the carrier, and is spring-urged against a cam surface, Fig. 2 (not shown), on the cam 115. When the punching operation is completed the cam surface allows the carrier to be spring-urged anticlockwise until the arm 75 of the carrier engages an adjustable stop, at which time the dies 15, 17 are aligned with the hole in the work. When the eyelet has been clenched the carrier is returned by the cam surface to its original position. The clenching dies 15, 17 are controlled by a toggle mechanism actuated by a cam in the same way as the punching tools 11, 13. The pivoted raceway 21, Fig. 6, is fed with eyelets by a rotary hopper 23. The lower end of the raceway normally remains beneath the die 17, moving with it when the latter is swung into its operative position; its movement is controlled by a roll 169, engaging with a vertically reciprocating cam 173, the roll being mounted on a pivoted element 163, which is provided with a slot 161 engaged by a pin 159 on the raceway, and which is urged sideways by a spring 167. The cam 173 is connected by a link 177, Fig. 3, to the forwardly extending arm 125 of the lever controlling the upper die 17 so that during downward clenching movement of the latter the cam thrusts the roll 169 to the left against the action of the spring 167, the raceway being swung out of the path of the die. If no eyelet is to be inserted a lever 181 pivoted on the element 163 is swung into a horizontal position in which a cam face thereof engages a vertical face 185 of the machine to hold the raceway retracted. The nipple pin 19, Fig. 3, slidable vertically in the die 17, is split at its upper end 189 and is frictionally held in a bore 187 in the plunger 123 of said die so as normally to move as a unit therewith; the pin is engaged by an arm 191, which is pivoted to the arm 79 of the lever controlling the punch 13, and which is engaged by a pin 197, Fig. 4. on said arm 79, so that as the punch is moved down the arm 191 forces the pin 19 down to enter the endmost eyelet in the raceway 21. The pin is frictionally held in this position moving with the die 17 and being lowered into the hole in the work, until it engages the lower die 15 at the start of the clenching operation, whereupon the frictional action of the pin is overcome so that it remains stationary while the die 17 completes its clenching movement; it is then returned frictionally with said die to its original position. The lower end of the raceway 21 supports the eyelet and is not swung out of the path of the die 17 until the pin 19 engages the die 15, so that frictional engagement between the pin, which is preferably cylindrical, and the eyelet is unnecessary. In order that the stroke of each of the four tools may be adjusted, the bearing pin of each of the operating levers comprises an eccentric extension of a bush 199 (shown in Fig. 1, applied to one pin only) journalled in the carrier 65; the position of the bearing pin is adjusted by a worm 205 which meshes with a gear segment 203 connected to and concentric with the bush. The machine is power-driven via a continuously rotating pulley 209, Fig. 5, running freely on the shaft 35; by operating the treadle the pulley 209 may be clutched to a collar 235 integral with the shaft 35, via an intermediate bush 211 carrying a pulley rim 213 (from which the hopper may be driven) and also running. freely on the shaft 35. The bush.211 is connected to the driving pulley 209 by means of a spring-urged dog 217 which may be rendered inoperative by pushing in a pin 225, thereby bringing the machine to rest. Movement of the collar 235 and hence of the shaft 35 is controlled by a boss 247, which, when withdrawn from engagement with a beak 245, enables a spring plunger 243 fixed to the beak and slidable in the collar 235 to engage a dog 249 on the rotating bush 211. When the boss 247 is returned it eventually re-engages with the rotating beak 245, pushing it back to withdraw the plunger from the dog 249 and stop the machine. The boss 247 is attached to the lower arm 251, Fig. 4, of a lever clamped to a stud 257 rotatable in the machine frame, this arm 251 carrying a roll 265 intermediately along its length. When the machine is at rest a tension spring 263 attached to the other arm 253 of the lever holds the boss 247 in engagement with the beak 245, holds a brake 261 pivoted on an eccentric portion 259 of the stud 257 against a cam 264 fast upon the collar 235, and holds the roll 265 in a depression 267 in a cam surface 269 on said cam 264. The machine is set in motion by upward movement of a strut 271, pivoted at 281 and spring-urged into engagement with the arm 253; this move ment rotates the arm 253 so that the boss 247 and brake 261 are withdrawn. The inner end of a lever 285 is also pivoted at 281, the treadle being attached via a rod 33 to the forward end of this lever which is centrally pivoted at 293 to an arm 295 pivoted to the machine frame at 287; the forward end of said arm 295 extends out of the frame and carries a hand-operated plunger assembly 301 by means of which the end 297 of the lever may be either fixed to the frame or free to move. A latch 307, pivoted at 293, is normally urged into engagement with part of an arm 313, integral with the arm 101 of the punching mechanism, by a spring 309 connected to lever 285 which is itself urged upwards by a spring 291. The total movement of the pivot 281 is limited by a controlling link 283, connecting the pivot 281 and the fixed pivot 287, with provision for sufficient play at the latter point to allow the mechanism to operate as described below. When the plunger 301 is in its projecting position, the end 297 of the lever 295 being free and the latch 307 in engagement with the arm 313, initial depression of the treadle results in pivotal motion of the lever 285 about the stud 281 so that the latch 307 is pulled down causing the punching tools to approach the work via the arm 101 and the toggles, the work then being repo