Patent GB-1256044-A (GB)
Title: Cup forming draw apparatus for containers and the like
Inventor: DUNKIN HERMAN
IPC: B21D24/10
Filed: 1970-04-16
Abstract: 1,256,044. Making hollow-ware; cupping; shearing. STANDUN Inc. 16 April, 1970, No. 18105/70. Headings B3A, B3Q and B3W. Apparatus for drawing cup-shaped articles through a stationary die 94 by means of a punch 170 comprises a hold-down 124, a drive for reciprocating the punch and hold-down and including fluid-pressure means for applying pressure to the hold-down, and a stop for limiting downward movement of the hold-down so that it does not engage the die. As shown, there are two staggered rows each of two punches, and the dies have outer cutting edges co-operating with blanking dies 118 for severing blanks from sheet. The punches 170 are mounted for slight radial movement on a ram 168 and the holddowns on a ram 70. Drive for the rams is by posts 68, 80, Fig. 4, from a shaft 52 which is driven, through an electromotor 42, belt 30, clutch-and-brake 50, and a drive shaft, by a central gear. Cranks 72 on each end of the shaft 52 drive the posts 80 and lift-and-fall cams 54 on the shaft drive the posts 68, the cam and crank drives including counterbalance, aircontrolled cylinders 84. The hold-down may be raised an extra amount to facilitate servicing by removing a rail 110, Fig. 9, and coupling the hold-down carrier 114 to the punch-ram 168 by clips 258, Fig. 1, which are removed from a control panel 36 to interrupt the electrical circuit and inserted in slots (264), Fig. 10 (not shown), in coupling posts (262) on the ram 168 and normally movable through openings in the carrier 114. At the start of a down-stroke, a surface 130 on the hold-down 124 is pressed by an annular compressed-air piston 134 and pins 140 against the blanking die 118, which acts as the stop eventually limiting downward movement of the holddown. A stripping platform 108, supporting the strip from which the blanks are punched, is lowered by pins 164 during blanking. Feeding strip.-Strip is drawn continuously from a reel 32, Fig. 1, by two pairs of rolls 230, 238, Fig. 26, driven by a variable-speed electromotor controlled so as to keep the size of a loop 242, Fig. 1, substantially constant. The rolls 230, 238 are driven at slightly different speeds to remove excess lubricant applied by a bath 236. An arcuate roller-conveyer 254 feeds the strip to feed-rolls (180), Fig. 2 (not shown), on the press which are rotated intermittently, through a lever 190, Fig. 8, link 188, rack 186 and a ratchet-pinion, by the crank 72, 192, Fig. 4. Scrap cutting and removal.-At the exit side of the press, Fig. 3 (not shown), several narrow blades 214, Fig. 24, coact with stationary lower blades to sever the inner lands between adjacent openings in the remaining strip. A broad blade reaching across the strip shears a projecting end of scrap which falls on to a conveyer (200). Ejection and removal: stop-mechanisms.- Drawn cups are stripped off the punches by spring-pressed fingers 104 and fall on to conveyers 174. If a beam energizing a photo-cell 178, Fig. 9, is more than momentarily interrupted by an ejected cup, the press stops. An additional stop mechanism, operative if the hold-down does not reach its holding position, comprises an inner and an outer track ring 144, 146, Fig. 12, surrounding the punch and mounted on the hold-down carrier. A probe 148 normally makes electrical contact with the ends 154 of the outer ring 146. If the inner ring 144 is displaced upwardly by the hold-down relatively to the outer ring, against the influence of springs 162, balls 158 and forced out of the track in the inner ring 144 thus expanding the outer ring away from the probe 148, Figs. 13 and 14 (not shown), and stopping the press. Sub-press mechanisms.-Guide-pins 166 maintain alignment between the die-holders 88, 114.