GB618920A - Improvements in crankshaft twisting machines - Google Patents

Abstract

618,920. Twisting crank-shafts. FITZPATRICK, H. J. (Clearing Machine Corporation). Nov. 13, 1946, No. 33645. [Classes 83 (ii) and 83 (iv)] A crank-shaft twisting machine comprises clamping dies on a base co-operating with dies on a press head for holding certain cranks stationary and co-operating clamps on the base and the press head which after closing are rotated to twist other cranks on the shaft. Separate means is provided for reversely rotating the clamps on the press head. A six-throw crank-shaft forged with the cranks in one plane is inserted into a press with clamps 29 on the base co-operating with clamps 34 on a press slide 23 for holding the end journals and cranks 2, 5. Cranks 1, 3, 4, 6 are clamped between members 39 on the base and members 40 on the slide. When the press head is lowered, the members 39, 40 are locked and rotated in the appropriate directions by hinged members 46, 47 actuated by cylinders 50, 51 to angles determined by adjustable screwed stops 69 on the press head. When the press head is raised, the upper clamps 40 on the head are rotated to normal position by cylinders 59 with pistonrods 60 engaging racks 63 on the clamps 40. Ejector mechanism comprises a beam 72 supporting rods positioned under the crank journals. After twisting, the press head 23 is raised by cylinders 26 to separate the clamps and attached cylinders 75 carrying detents 77 are lifted and engage beneath heads 74 on rods 73 attached to the beam 72 to lift the rods and the shaft for removal. Hand operation of a valve 86 releases the detents 77 to allow the beam to drop by gravity to an inoperative position. In operation, the shaft is positioned and the press head is lowered by cylinders 26 to close the fixed clamps 29, 34 and the rotary clamps 39, 40. The cylinders 50 swing the actuators to rotate the clamps 39, 40 to effect twisting. The slide is then raised and pressure is admitted to the cylinders 51 to rotate the lower members 39 to normal position after a stop 66 on the press head has operated a valve 65 admitting pressure to cylinder 59, restoring the clamp 40 to normal position and the beam raises the shaft ready for removal.