Patent GB-739901-A (GB)
Title: Means for and methods of producing preassembled nuts and washers
Inventor: NIELSEN MORITZ HERLUF
IPC: B23P19/08
Filed: 1952-02-06
Abstract: 739,901. Making nut and washer assemblies. ILLINOIS TOOL WORKS. Feb. 6, 1952, No. 3158/52. Classes 83 (2), 83 (3) and 83 (4). Means for manufacturing permanently assembled nuts and washers is formed from a screw machine, of the work-spindleturret type, by replacing one of the sliding tool-holders and the related side-working tools by means for feeding a connected strip of washers and includes means for detaching the leading washer, assembling it on a spigot on the nut, and expanding the spigot to render the washer captive whilst still free to rotate relatively to the nut. Tapping takes place subsequently to the assembly and the assemblies pass over the covered tap shank for discharge to a funnel leading to a receptacle. The invention is described with reference to a five-spindle machine with stockguide-tubes 26, Fig. 1, mounted at the spindle end in a disc 28 and at the outer end in a flanged-disc 32 supported by two rollers 34 carried by a pedestal 36. Both discs are keyed to a shaft 30 that rotates with the turret. A front cam-shaft 526 operates the index bolt for the turret at 44, the turret rotating means at 40, the chuck at 46 and the stock feed at 24. Cam-shaft drives.-All the parts are driven by a single motor 478 driving through a chain and sprocket, and the shaft 526 is driven through a one-revolution clutch from a camshaft 510 provided with a hand-wheel 535 for use in tool-setting ; a hand-operated clutch on a third motion shaft permitting of disconnecting all the cam-shafts from the power drive. The third motion shaft drives, through bevel gears, the shaft 510 that, through an intermediate shaft and change gearing, drives a cross shaft 546, Fig. 4, carrying worms driving front and rear cam-shafts 102, 104 that are bevel geared at 560, 562 to opposite ends of a transverse cam-shaft 120. Tool feed-motions.-The sliding tool-holders are fed through adjustable links 140, Fig. 6, and levers 126 from a series of cams 110 on the shaft 120 and the cross slides 66, 68, Fig. 11, and lever rests 70, 72 are similarly linked at 94 to levers 86 operated by cams 78, 80 on the shafts 102, 104. Making nuts.-The stock bar is fed at station A, Fig. 11, and a side tool 58 turns the spigot 568, Fig. 32, that is to receive the lock washer, and the blank is centre-drilled by a tool 152 carried by the sliding tool-holder 48. At station B the sliding tool-holder 50, Fig. 33, drills the blank and a cutter 156 end-faces the spigot whilst a side cutter 60 starts the parting off. At C a single-point boring tool 164, Fig. 34, carried by a block 160 pivoted to the sliding tool-holder 158 and held by a spring 166 so that adjustable strips locate the tool concentric with the axis, is fed into the bore to the depth shown, whereupon a bar 170, carried by the chamfering tool 62, engages an adjustable screw stop 172 and feeds the tool laterally to chamfer the inner end of the bore. At D the washer is supplied and at E the nut is parted-off and tapped. Supplying blanks; tube expanders.-A strip 4, Fig. 1, of internally-toothed lock-washers connected by contacting teeth 7<SP>11</SP>, Fig. 24, the connection being in part broken when the teeth are twisted, is fed from a reel 3 and passes over a guide 270 and through a feed member 276, reciprocated by an arm 278 on one of the sliding tool-holder feed-levers, to a guide 272 whence it passes over a curved block 260, Fig. 16, to a channel tangential to a feed wheel 206 mounting chamfered pins 204 that enter the holes in the washers and forward the strip through a channel in a fixed block 310, Fig. 26, to a channel in a pinion 304 oscillated through a quarter turn by a rack 338, Fig. 14, carried by a bar 342 adjustably mounted at 346 in a block 364 carried by a sleeve 350 that takes the place of the sliding tool-holder at station D. The sleeve is pinned to a reciprocating bar, cam-operated at 354, and both sleeve and bar have a keyway sliding over a stop key 358 adjustably fixed at 362. The block 364 also supports a bar 262 carrying a slotted head 264, Fig. 19, engaging a pin on a lever, pivoted about the shaft carrying the feed wheel 206 and a ratchet wheel 216, and carrying a pawl 222 kept in engagement with the wheel by a spring 224. A spring detent 228 is also provided. The position of rest of the ratchet wheel is adjusted by a stop pin 238 carried by a rod 234 settable by a spring 242 and nut 246. The pawl may be rendered inoperative by raising the rod 234 by the knob 248 on the sleeve 246 to allow a spring latch 250 to snap beneath the sleeve. The adjustment ensures that the plane of junction of the teeth 7" lies in the contact plane of the block 310 and pinion 306 so that the oscillation of the pinion breaks off a washer that passes by a channel 320, Fig. 14, to become located in front of a reciprocating sleeve 173 and plunger 188. Pins 324, Fig. 26, sliding in slots as controlled by backing pins 332 and leaf-springs 336 ensure that the washer is correctly fed by the sleeve 173 and plunger 188, Fig. 35, to place it on the nut-spigot, after which further advance of the plunger expands the spigot by its conical surface 190 and renders the washer captive. The plunger is carried by a bar 184 pinned to the sleeve 350, and relative movement of the plunger and sleeve is permitted by a spring 194 on contact of a cap 196 with the stop key 358. This ensures that the end of the sleeve occupies a correct position in relation to the supply channel 320. A stop 374 engages a head on the rack-bar 342 and ensures that the channel in the pinion is in register with the supply channel for the strip. Two modifications, Fig. 42 (not shown), and Fig. 46 (not shown), are described of the means for ensuring correct guiding of the washer on to the spigot of the nut. Tapping; chucks.-At station E a spring collet 390, Fig. 30, is carried by a sleeve 386, splined in an outer sleeve 376 with a countersunk end 393 that effects bevel-closing of the collet. The sleeves are continuously driven at 380 in synchronism with the stock spindles. The inner sleeve 386 carries, beyond the end of the outer sleeve, a block 394; a ball bearing 396 being interposed. An actuating-sleeve 424 for the chuck is cam-operated and acts, through levers 420 engaging the ends of keys 404 sliding in slots in the sleeve 386 and bearing against the end of the outer sleeve, to feed both sleeves towards the spindle-turret until the block 394 contacts a stop 452 and the inner sleeve is arrested with the collet surrounding the nut as in Fig. 36. The bevelled surface 426, Fig. 30, then acts on the levers 420, forcing them inwards and closing the chuck about the nut. In the closed position of the chuck a stop 474 prevents further advance of the sleeve 424 relatively to the block 394. The nut is now held and driven both by the stock-bar and the chuck. A side cutter 64, Fig. 36, now completes the parting-off and the sleeves 376, 386 retire together carrying the nut over the non- rotating tap 462. When the nut has passed to the shank of the tap, the block 394 contacts a stop 454 and the chuck is opened. The finished nuts pass along the tap shank for discharge into a funnel 472, Fig. 1.