GB861516A - Improvements in chucks for automatic lathes - Google Patents

Abstract

861,516. Chucks. HAHN, E., [trading as INDEX-WERKE KOMM.-GES. HAHN & TESSKY]. Dec. 19, 1958 [Feb. 15, 1958], No. 41115/58. Class 83 (3). In a collet-chuck for automatic lathes, additional work-clamping jaws 53 for workpieces 81 having headed portions 82 are pivotally connected to an axially displaceable clamping device 50, which co-operates with the collet-locking mechanism. The lathe spindle 25, Fig. 2, contains a collet 38 actuated by a lever 31 which axially moves a sleeve 44 carrying a bevel-closing member 40. In operation, starting from the position of Fig. 2, wherein the lever 31 forces the sleeve 44 to the right, the workpiece 81 is clamped by the jaws 53 and by the collet 38. To release the work, the collet is unlocked by movement of the sleeve 44 to the left, and a sliding head 23 is then moved to the right by a lever 28, and carries with it a rod 56 which, through a spring 65, moves the head 50, jaws 53 and work out of the collet. This continues until nuts 71, carried by a sleeve 55 connected to head 50, engage a stop 75 to prevent further movement of head 50. In this position, jaws 53 are free to swing outwards by centrifugal action, and rod 56 continues to advance, compressing spring 65 to eject the work. This movement of rod 56 is arrested by a stop-collar 68 thereon. Levers 28, 31 are operated by a cam drum 30, Fig. 1, and workpieces 15 are supplied to the chuck from a shoot 16 by a pusher 17 to a receiving member 18 on a turret 12, which is indexed, and are removed after machining by a part 19 on the turret from which they are stripped.