GB499182A - Improvements in and relating to hand-protecting apparatus for presses and the like - Google Patents

Abstract

499,182. Machinery guards ; utilizing inertia in machinery. GUINOT, E. May 25, 1938, No. 15662. Convention date, May 25, 1937. [Class 80 (iv)] A guard 36 for a press or like machine is held in the raised position shown when the machine is at rest. A ring 6, loose between discs 2, 3, keyed on the power shaft 1 is slotted at 8 to take a pin 10 fixed in the disc 2 and carrying a roller 9 working in a radial slot 1 in the disc 3. When a control 16 is moved to throw in the clutch and the shaft 1 rotates, the ring is held by a lug 12 and spring 20 until the pin contacts with the end a of the slot 8. A hammer 11 is mounted on the inner end of the pin and in the position shown holds down the nose 22 of a lever 23 to which the guard is connected through latch mechanism and a flexible cable. When the hammer is carried round with the discs the lever 23 is released and the guard allowed to fall. It is then locked by a latch 28. Further rotation of the shaft carries round the ring 6. When the machine stops at the end of a working stroke the discs stop in the position shown, but the ring 6 is carried on by its momentum. During this overrunning movement the pin 10 is forced down the slot 13 by the inclination of the slot 8 so that the hammer 11 strikes the nose 22 to release the latch and allow the guard to be raised. In a modified construction the hammer is moved out by a cam surface on the ring and inwards by a spring. In a further modified form the lever 23 actuates an electric switch and relay device controlling the latch mechanism.