Patent GB-669646-A (GB)
Title: Improvements in and relating to work handling apparatus
IPC: B21D43/10
Filed: 1949-01-12
Abstract: 669,646. Stamping. SAHLIN, H. Jan. 12, 1949 [Feb. 11, 1948], No. 909/49. Class 83 (iv). [Also in Group XXX] Work-handling apparatus for a press or like reciprocating machine comprises a workhandling arm pivotally mounted on a slide mounted for reciprocable movement along a rectilinear path, the arrangement being such that on shifting the slide in one direction a part of the work-handling arm is engaged by means causing it to swing relatively to the machine. Figs. 1, 2 and 5. A pendant work-handling arm B consists of a pair of telescopic tubes 41, 42 and a pair of side-plates 26 secured to the top of outer tube 41 and pivotally mounted on bolts 29 provided on the slide 27, slide 27 being in turn slidable vertically on a guide-shaft 15 secured to the press or the like. A cam 20 adjustable vertically by nuts provided on studs 18, 19 by which it is secured to the press or like machine co-operates with a pair of rollers 24 mounted on the side-plates 26 such that upon raising the slide 27 arm B is first raised vertically and then swung away from the jaws 11, 13 of the press or like machine and upon lowering the slide arm B returns by gravity to a pendant position adjacent the jaws 11, 13. Figs. 2 and 9. The length of the telescopic portion 41, 42 is adjusted by means of a screwed rod 45 provided with nuts, and at the lower end of the inner tube 42 is fixed a guide-plate 49 on which slides a block 51 provided with an integral gripper 52 and a second gripper 53 pivotally mounted on it. In the lowered position of the arm the grippers are adjusted vertically to lie opposite a stamping P in the press or like machine. Block 51 is slidable towards the pressing by a fluid cylinder and piston 55 whereupon an arm 53a on the gripper 52 engages the forward edge 57 of a groove 50 in the plate 49 to cause the grippers to grip the stamping, which has been knocked up slightly by pins in the press. Figs. 1, 2 and 5. In order to control the operation by the press or like machine a camoperated switch arrangement 65 is associated with the drive-shaft of the press or like machine so that as the stamping is knocked up a switch closes, causing an electromagnet valve 60 to supply fluid simultaneously to cylinder 55 and also to a cylinder 36 whose piston is adjustably secured to the slide 27. Cylinder 55 which is under a light load acts first to grip the pressing as set out above whereupon cylinder 36 raises the slide 27 so as to first raise the arm and then swing it outwardly. At a desired point of the swing a roller 73 vertically adjustable on the slide 27 contacts a button 72a so as to operate a switch 69 which cuts off the current to valve 60 and so causes the latter to supply fluid to the other end of cylinder 55 and to connect the first end of cylinder 55 and cylinder 36 to exhaust, whereby the block 51 slides back on the plate 49, arm 53a contacting end wall 58 of slot 50 to open the grippers and deposit the pressing, after which the arm B descends by gravity, slowly exhausting cylinder 36, to its original position ready to remove another work-piece. By adjusting the height of the roller 73 the pressings can be deposited right way up or inverted on a receiving table, as desired. The apparatus can be adapted to feed pieces to the press instead of removing the stampings.