GB602383A - Improvements in or relating to die-stocks for cutting conical or cylindrical screw threads - Google Patents

Abstract

602,383. Screwing die-heads. RICKENMANN, A. Oct. 13, 1945, No. 26834. [Class 83 (iii)] In a die-stock for cutting conical or cylindrical threads automatic adjustment of the dies is effected by the return movement of a sliding housing. Dies 6 are housed in a frame 8, and unidirectional work gripping jaws 11 in a frame 13, Fig. 1, the two frames being bolted to opposite ends of a body 1 on which is rotatably mounted an operating member 2 having a worm-thread 36 and carrying a spring-loaded ratchet 32, Fig. 4 engaging circumferential teeth on the body 1. A casing 3, Figs. 1 and 3, has journalled therein a spindle 37 having a worm 371 engaging the thread 36, and a gearwheel 38 meshing with another gear-wheel 22, Fig. 2, mounted on a spindle 21. This spindle is threaded, to move axially a block 24 engaging one of the dies whereby the dies move each other to vary the diameter D. In a similar manner the work-gripping jaws are moved to accommodate varying sizes of work. According to the setting of the ratchet 32, so either left or right-hand threads will be cut by the dies, the oscillatory movement of the member 2 moving the assembly against the stationary work in one direction to cut the thread, whilst in the reverse direction the jaws 11 grip the work giving relative motion between the body assembly and the operating member 2, causing the dies to be opened for the next part of the cutting operation. For cutting cylindrical threads, the spindle 37 is displaced axially to disengage the die opening drive between the worm threads.