Patent GB-533358-A (GB)
Title: Improvements relating to machines for assembling washers on screws or the like
IPC: B23P19/08
Filed: 1939-07-11
Abstract: 533,358. Feeding washers and bolts. EVERY, C. E. (Illinois Tool Works), July 11, 1939, No. 20200. [Class 117] [Also in Groups XXII and XXX] Washers are assembled on screw blanks, nuts or like fastener elements, prior to rolling the threads or otherwise depressing the metal to prevent separation, by blank-transferring mechanism that deals with loose masses in hoppers, the device being constructed as an attachment for existing thread-rolling machines and provided with its own source of power. The hopper 14, Fig. 1, is supported from a casting 34 adjustably mounted on the machine frame at 528, further adjustments being provided at 526 and 30. Blanks are raised from the hopper by a plate 94 reciprocated by a crank and connecting rod 98 and pass down an adjustably mounted shoot 36 assisted by a driven clearing wheel 106 of ratchet form where the rails leave the hopper. One of the rails 42 forming the shoot carries a vibrator sleeve 118, Fig. 3, containing a spring plunger 116 prevented from rotating by a pin and slot 124 and reciprocated by cam pins 132 in a pulley driven by the belt that drives the clearing wheel. The washers are contained in an inclined cylindrical hopper 136, Fig. 10, having a wear-resisting sleeve 150 and a notched disc 138 rotating step by step on an annulus 146. The disc is loose on the hub of a cam 200 mounted on a fixed pin 202 and driven by a worm-wheel and worm 210. The cam engages a roller 250, Fig. 14, on one arm of a three-armed lever having an adjustable eccentric pivot 260, the arm 256 being actuated for the operative stroke by an adjustable spring 261 and the arm 252 carrying a pawl 244 pivoted at 246 and engaging a ratchet wheel secured to the disc 138. The pawl and a detent 270 are held in engagement with the wheel by a spring 263. Washers are carried upwardly by the disc and, should two washers adhere together, the surplus washer is removed by a series of fingers beneath which the notches pass. Beyond the last finger the correctly positioned washers pass beneath a spring plate 495 having a finger that coacts with the rail 44, of a further shoot, to prevent the washer from tipping during insertion of the screw. The shoot guides the screw and washer after assembly and removes them from the notched disc. As the pawl moves clockwise round the ratchet wheel on its idle stroke a pin 316 on it engages the side 314, Fig. 15, of a notch in a ring 310 loose on the hub of the ratchet wheel and provided with a further notch 308 that engages the end of a finger 296 adjustably mounted at 304 on a level at 320. The ring advances the finger through a slot in the rail 44 until the end of the finger clears the notch when a spring 318 returns the lever. If screws have become jammed in the shoot the finger is not free to move and the side 314 cams the pin 316 lifting the pawl clear of the wheel and preventing indexing. The notched discs are changed to suit the size of washer being fed and the hopper and its parts are adjustably mounted so that the washers may be correctly positioned on the rails 44, 46 at the assembly station. The annulus 146 has a gap to admit the rails and the detector mechanism an adjustable wedge piece 322 affording continuity of support for the washer passing on to the rails. The distance between the rails is regulated to suit the screws by an adjustable wedge 72, Fig. 8, and brackets 80 support guard rails 78 above the heads of the screws with eccentric adjustment at 86. The screws are taken from the shoot 36 by fingers 396, Fig. 26, for insertion into the washers. The fingers have end plates 400 notched at 402 and in the screw receiving position the fingers are separated sufficiently to allow a blank to pass at 406 but not at 404. The inserting device 352 is mounted on a U-shaped casting 344, Fig. 1, straddling the washer hopper and it is operated by a cam 276, Fig. 10, coaxial with, and driven by, the cam 200, and engaging a plunger 452, Fig. 22, having contact, adjustable at 462, with a lever 458 pivoted at 362 and carrying a sleeve 470 permitting the use of a long spring 464 that is operative on the inserting stroke. The end 476, Fig. 26, of the lever passes through slots in the casing 354 and sleeve 368 to engage the plunger 370 that has a limited movement in the sleeve under the control of a spring 388 and stop nuts 378. Upward movement of the sleeve 368 in the casing is limited by a shoulder 390 and cap nut 384, and in this position an internally coned sleeve 416 adjustably fixed in the casing at 420 engages the tops of the fingers, rocking them about projections 408 by which they are retained, with the help of a garter spring 412, in grooves in a member 392 on to the sleeve 368. As the sleeve and plunger descend, the fingers are closed on to the screw by a spring 430 and sleeve 436. When the screw blank is fully home in the washer a shoulder 438 in an adjustable sleeve engages the lugs 442 and opens the fingers. To prevent a screw blank from being fed should a washer be absent, a lever 482, Fig. 14, is urged by a spring so that a feeler end 488 is in the path of the washer. Above the feeler is a plate 486 above the plane of the washer. When a washer is present the lever is cammed back and the plate is removed from the path of the blank. Otherwise the plate engages the end of the blank, the plunger 370 cannot descend, and the blank is retained in the fingers preventing the feeding of a further blank on the next stroke. The blanks are transferred from the rails 44, 46 to the thread rolling dies 20, 22, Fig. 4, by an adjustable finger 522 on a slide 514 fed by a spring 520 and returned by a cam 516 on the movable platen. A finger 512 on a slide 510 ensures the entry of the blank between the platens. In a modification the attachment is mounted on a pillar separate from the frame of the rolling machine, and the blanks are raised from the hopper by a curved cam-operated blade grooved at the top edge to receive these shanks: In the raised position the top edge forms a continuation of the rails forming the shoot. Specifications 514,336, 514,347, 519,529, [Group XXII], 519,563, [Group XXX], and 521,987, [Group XXV], and U.S.A. Specification 1,584,264 are referred to.