GB1086651A - Flying cut-off - Google Patents

Abstract

1,086,651. Flying shears. YODER CO. Jan. 6, 1965 [Jan. 8, 1964], No. 589/65. Heading B3W. A flying shear particularly adapted for cutting moving tubing comprises a doublesided cutter B mounted in a rectangular frame 66 which is reciprocated on guide rods 55 and 56 by the piston rod of a double-acting compressed air cylinder 17. Assuming the frame 66 to be at the left-hand end of its stroke, a pin 81 is held by a latch 83, while high pressure air is admitted to the left-hand end of the cylinder 17. When the latch 83 is disengaged by a solenoid 94, the cutter accelerates rapidly and passes through the tubing T. When the piston is half-way along the cylinder 17, exhaust ports 48 and 49 are uncovered, the supply of high pressure air is cut off and low pressure air is admitted to the right-hand end of the cylinder to decelerate the piston. The return stroke which is also a cutting stroke is made by reversing the air connections to the cylinder 17. The air valves are solenoid operated and the cycle of operation is initiated when the leading end of the tubing operates a limit switch. In order to allow for the finite movement of the tubing during the cutting stroke the cutter B is mounted in a sub-frame 117, Fig. 8, which can move on guide rods 108, 109 in the frame 66. Springs 123, 124 return the cutter to its original position after the cutting stroke. During the cut the work is held on either side of the cutter by split clamps, one pair of which 186, 187 is shown in Fig. 7. The clamps are closed by a fluid cylinder 197 which operates a wedge 179. The clamps are mounted on a carriage which slides on guide rods 163, 164, so that when the clamps engage the material, the whole carriage moves with the material. Springs return the carriage to a position determined by stop nuts 232. Cutter shape.-The cutter B is symmetrical about vertical and horizontal centre-lines and comprises a rounded point 137, Fig. 9 (not shown), a pair of arcuate, concave, outwardly flaring surfaces one on each side of the point each leading to and blending with an arcuate convex surface, followed by a further arcuate concave surface.