Patent GB-1389582-A (GB)
Title: Devices for feeding strip stock to punch or like presses
IPC: B21D43/11
Filed: 1972-01-11
Abstract: 1389582 Metal stock feeds A W SCRIBNER 11 Jan 1972 [14 Jan 1971] 1315/42 Heading B3W [Also in Division F2] A device for intermittently feeding strip stock into the work station of a punch press comprises a pair of slides 30, 30a reciprocated by fluid motors 80, 80a, grippers 51, 51a carried by the slides and actuated by separate fluid motors 60, 60a and a control valve 125 including cooperating members 130, 131 which are relatively rotatable to supply and exhaust fluid pressure sequentially to and from the fluid motors to cause the slides to carry out feed strokes alternately. Dovetail grooves in the slides engage complementary tongues on a block 24 and the slides run between a fixed rear stop 32 and a front stop 33 adjustably mounted on the block 24 by means of two screws 34, 35 which threadably engage a plate 36 screwed to the block 24. The gripper levers 51, 51a are pivoted in blocks 53, 53a which are screwed to the slide bodies 50, 50a by screws 55, 55a which extend into hexa gonal coupling members 95, 95a on the piston rods (94), 94a of the double-acting fluid motors 80, 80a. The gripper levers, pivoted to gripping position by single-acting fluid motors 60, 60a, are returned by springs 70, 70a. Fluid-operated buffer pistons 102, 103 housed in cylinders (100), 101 are actuated alternately to damp the end of the feed strokes of the slides. Sets 155-158 of apertures in the outer valve member 131 register respectively with sets 150-153 of grooves in the inner member 130. The relative dispositions of the grooves and apertures is varied through rotation of the member 130 by means of bevel gears 134, 135 driven by the press crankshaft. The set of grooves 150 for controlling the fluid supply to the motor 60a comprises a supply groove 170, fed from a valve core passage 133 via a hole 172, and exhaust grooves 173, 174. The corresponding set of apertures 155 comprises an exhaust aperture 160 and an aperture 161 connected to the motor 60a. Rotation of the member 130 causes the aperture 161 to register alternately with the supply groove 170 and the exhaust grooves 173, 174. The remaining sets of grooves and apertures are for the supply of fluid to the other gripper-actuating motor 60 and the head ends of fluid motors 80, 80a. Fluid is supplied to the axial passage 133, feed lines to the rod ends 92, 92a of motors 80, 80a and line 114 to the buffer cylinders (100), 101 via pressure regulators (192-194), Fig. 1 (not shown). The timed relation of the rotation of the member 130 to the press operation is such that either slide 30 or slide 30a executes a feed stroke between consecutive punch strokes. The member 131 is normally fixed but may be rotated by means of a set screw 148 and a slot in bracket 147, Fig. 3, and vary the phasing of valve 125 with the press operation. Alternatively, Fig. 12 (not shown), a conventional centrifugal speed sensing device (215) can rotate the member 131 to vary the phasing of the press and the feed device in response to changes in press speed and to adjust a pressure regulator in the fluid supply lines to the buffer cylinders and for the rod ends of the fluid motors 80, 80a. In an alternative form of valve 125, Fig. 14 (not shown), fluid is supplied via apertures such as (161a) and exhausted via the axial passage (133a).