Patent GB-587883-A (GB)
Title: Improvements in or relating to stamping or drawing presses
IPC: B21D22/06
Filed: 1943-09-17
Abstract: 587,883. Cupping. GENERAL MACHINERY CORPORATION. Sept. 17, 1943. No. 15296. Convention date, Sept. 17, 1942. [Class 83 (iv)] Stamping and drawing presses have the actual mechanism 93, 96, 90, Fig. 1, carried upon the press-head 22 and moves with it, the die reaction being transmitted to the base 20 by tension members. The head is guided by side members 21 bolted to the base and linked at the top by detachable bars 41. The head may carry a cover as indicated in dotted lines to enclose the gearing. The motor 93 drives by V-belts 94, Fig. 3, a fly-wheel 96 loose on its shaft to which it is connected by an air-operated clutch connected in series with a brake so that when the clutch is engaged the brake is off and conversely. The control valve is actuated electrically by a switch controlled manually by a push-button. A limit switch 141 is also provided chain-driven at 143 from one of the eccentric shafts to stop the press with the eccentrics at the upper deadcentre. The clutch-shaft has a pinion 100 driving gears 105, 105<1>, preferably integral with the eccentrics 90 and their shafts, through the reduction gearing indicated in Figs. 3 and 4. The eccentric rods 87 are pivoted at 85 to ,yokes 86 on screwed rods 60 guided at 54, on members 51 secured to the side members 21, to take care of side thrust due to obliquity. The head 22 is guided in the side members at 44, 44<1>, Fig. 7. The nuts 61, Fig. 6, are mounted in housings 62 bolted to the side members 21 and these are anchored to the base by tie bolts 40, three to each rod, and fitted with nuts 40<1>. These are preloaded by placing jacks on the bed and exerting pressure against the head 22. Any space developed between the side members 21 and the bed is packed with shims, thus retaining the load on the bolts 40 when the jacks are removed. The nuts 61 are provided with worm-wheel teeth engaged by worms 65 on shafts journalled in the housings and connected along the front and back of the press by removable intermediate shafts. The shafts are bevel-geared at one end of the press to a cross shaft driven through reduction gearing from a motor when adjustment is required to be made. In a modification, the nut housings are directly connected to the base 20. The screwed rods 60 are protected from dirt &c. by telescopic guards, the outer sections 160, Figs. 6 and 13, having a flange 161 for attachment to the yokes 86 and the inner section 163 having a flange 164 for connection to parts 21<1> of the side members 21. The intermediate sections 166 have upper outer flanges 168, to coact with flanges 165 on the sections 160, and lower inner flanges 167 to coact with flanges 170 on the intermediate sections 169. Holes 172 in the base are fitted with thimbles 173 to receive and cover the ends of the rods 60 in their lowest adjusted position. A brake for arresting the fly-wheel, when required, comprises a shoe 150, Fig. 12, pivoted to a lever 151, itself pivoted to a support 152 and provided with a lug 156 for engagement by the rod of air-actuated piston 155. The head 22 is balanced by rods 190, Fig. 4, centrally arranged on each side and carrying pistons 191 in cylinders 192 carried by the base and supplied with pressure fluid at 193. Cushion cylinders 34 have pistons connected in the usual way by pins passing through holes 35 in the bolster 30 and supporting the draw ring. Specification 312,640, [Class 83 (iv)], and U.S.A. Specification 1,872,115 are referred to.