Patent GB-519529-A (GB)
Title: Improvements in machines for assembling washers on screws
IPC: B23P19/08
Filed: 1938-08-24
Abstract: 519,529. Shoots and hoppers. JENNINGS, H. W. K., and EVERY, C E. (Illinois Tool Works). Aug. 24, 1938, No. 24936. Addition to 514,347, [Group XXII]. [Class 78 (i)] [Also in Group XXII] An unthreaded screw blank, Fig. 39, automatically moves along and picks up a locking washer both then being pushed between reciprocated grooved platens to roll a thread thereon, the increased diameter of the thread preventing the washer from falling off. Screw blanks are fed from a hopper 28, Fig. 1, by a reciprocating plate 72 and clearing wheel 74 to slide down an inclined guide shoot 12 and are delivered to a transverse channel 56, Fig. 24. The blank injector 20, Fig. 24, is operated by the starter slide bar 366 to eject the blank from the channel 56 into an assembler wheel 10. Lock washers are fed from a hopper 4, Fig. 14, by feeder 112 disc 148 and clearing device'206 to a guide shoot 8, Fig. 1, down which the washers gravitate, an intermittently operated hammer jarring the shoot to facilitate movement of the washers. An assembly wheel 266, Fig. 17, of the assembler 10 is intermittently rotated by driving mechanism 18, Fig. 1, actuated by driving mechanism (38, Fig. 2, not shown) so that screw blanks are carried successively into engagement with the leading lock washer in the chute 8 and each assembled unit is moved along guide plate 393 and guide bars 394, 396, a resilient cam surface 400 causing the washer to contact eventually with the periphery of the assembly wheel 266. The blank and washer are brought round by wheel 266, which stops so that an ejector 412-22 moves the unit into the transverse guide channel 58, Fig. 24, a spring clip 66 impelling the unit along the longitudinal channel in the lower portion of the guide shoot 12. The units now gravitate down 12 to a resilient clamper 522, Fig. 24, controlling the feeding of the unit to the transfer guide chute. 430 from which a transferer 14 moves each unit between a reciprocated screw threading platen 34 and a fixed platen 32. If a washerless screw blank is fed to the guide shoot 430 the transferer 14, in moving out or back carries the washer or blank out and drops it into a channel from which it gravitates into a central opening and then gravitates along a channel into a receptacle 564. When the reciprocating gate' (448, Fig. 2, not shown) begins to move the platen 34 the starter mechanism 26, Fig. 4, actuated by spring 670 and cam (642, Fig. 3, not shown) of operating mechanism to move starter finger 612 forward to engage the shank of the blank and pushes it between the platens. The platens are bevelled at the ends to facilitate insertion of the blank. The platen 34 moves slightly beyond the platen 32 so that the finished screw and washer drops into a receptacle 564. In the modified assembler shown in Figs. 32 'to 38, the assembled washers and screw blanks are received in washer size pockets 682 formed on the outer periphery 288 of the assembly wheel 266. A modified ejector 22<1> is rendered inactive if a washer is absent from a blank. a cam lug 704 is free to move into the pocket 682 so that spring 712 rocks lever 698 clockwise Fig. 22, to position, Fig. 33, so closing contacts 714, 716 energizing a solenoid 686 to withdraw a slide bar 692 and lever 698 into position shown in Fig. 36, so that the screw blank will not be ejected from the assembly wheel 266 but will be carried round through positions A, B to C, Fig. 17, to extract the leading lock washer from the chute 3. If a blank without a washer is held in the assembler by fore and aft units in the lower position of the guide shoot the spring pressed slide bar 692 can be moved back by such blank so preventing damage to 'the assembler by this jamming of the ejector. A modified washer receiving hopper 722 and washer feed 724, Fig. 41, may replace the hopper 4 and feeder 6, a feed plate 744 oscillating about 752 by an eccentric. 756 driven by sprocket 764 and chain 766 from the driving shaft. The washers gravitate along a smooth top plate 776 into the hopper. A knurled clearing or feed control roller 786 driven by chain 800 is provided to sweep back washers not in the groove in the plate. A rubber ended hammer 808 vibrates the guide shoot 778 to help the washers along under gravity. For periphery toothed lock washers the bottom and side bars of the shoots 778 are notched at 820, Fig. 43, to receive the teeth of the washers. The top edge of the oscillating feed plate 744 lifts up washers from the hopper 722 and tips them towards the guide shoot 778; some washers being thereby fed to the inclined top plate 766-and enter shoot 778 and gravitate along. The toothed cleaning roller 786 engages the washers deposited on the top plate 776 and prevents them escaping otherwise than along the chute 778 and by agitation of the washers causes them to fall into the guide shoot 778, washers adhering to the toothed roller 786 are scraped off by a felt &c. at 828 engaging the periphery. The hopper 722 and feed 724 can be simultaneously adjusted about a stud 80 and an arcuate slot 834. Idler sprockets tension' the chains 766 and 800. Modified washer injectors 854, Figs. 47, 48 and 53 and ejectors 856, Fig. 54, transfer a screw blank to the wheel 266 of the assembler 10 and eject from the assembler to the shoot 12. The injector 854 has a notched lever 858 to receive the leading screw blank from the shoot 12 and with the help of angle plates 868 and 878 guides the head of the blank during injection of the blank into the assembly wheel 266, the blank axis being preferably radial to the wheel 266 during transfer. The nose 872 of the plate 868 stops further feed from the shoot 12 temporarily during injection into the assembler. The modified ejector 856 in .Fig. 54, comprises a notched block 888-890 to receive the shank of the blank and, extending beneath the periphery 288, Fig. 52, of the assembly wheel supports the washer of the assembled units during ejection from the assembly wheel and transfers it to the lower section of the shoot 12. A cam (416, Fig. 20, not shown) on the assembly wheel operates the ejector bar 884. The injector mechanism 854 is preferably operated by the ejector mechanism by a pin 870, Fig. 48, on the lever 858 which, on ejection'is moved towards the guide shoot 12 into position to receive the leading blank from the upper section of the guide shoot 12. 'A coil spring 894 joining pin 870 and ejector bar 884 operates injector lever 858 in the opposite direction simultaneously with the movement of ejector 884 into. position to receive the next assembled unit, and also provides a yielding connection to prevent damage if the ejector becomes jammed. If either the injector or ejector becomes jammed a spring (420, Figs. 23 or 24, not shown) allows the assembly wheel to complete its normal cycle without breakage.