GB453332A - Improvements in electrical chucking mechanism for multiple spindle automatic chucking machines - Google Patents

Abstract

453,332. Lathes; chucks. NATIONAL ACME CO., 131st Street, Cleveland, Ohio, U.S.A.-(Assignees of Simpson, C. W.; c/o National Acme Co., 131st Street, Cleveland, Ohio, U.S.A.) Feb. 28, 1936, No. 6043. Convention date, Nov. 19, 1935. [Class 83 (iii)] An automatic chucking machine has a turret carrying a number of rotatable work spindles and a single electric motor located at the work-changing station, means being provided and operated by the machine at a predetermined time for moving an axially slidable shaft, rotated by the motor, into engagement with the chuck-operating mechanism within the spindle at the work-changing station. Means are also provided for stopping and braking the spindle at this station. The machine comprises a bed 2 supporting vertical housings 3, 4 connected by a beam 5, the housing 3 containing the turret for the workchucks 7 and the housing 4 containing gearing. A sleeve 8 through which passes the driving shaft for the chucks supports the tool slide 10. The chucks 7 are carried by hollow spindles 12, Fig. 3, and the jaws are operated by levers (not shown), rocked by a drawspindle 15 splined at 16 within the spindle 12 and screwed at 17 for co-operation with a rotatable bronze nut 19. The nut is held axially on the spindle 12 by a thrust bearing 20 and adjustable nuts 22, 23 locked by a key 24. All the spindles 12 are rotated from a central gear through friction clutches 13 which are disengaged in turn at the workchanging station by means of a yoke-operated spool 14, a brake B being applied to stop rotation of the spindle. The nut 19 at the work-changing station is rotated to open and close the chuck by a rotatable and slidable shaft 30, Figs. 3 and 6, splined within a worm wheel 38 mounted in a casing 31 suspended from the beam 5. A reversible electric motor 32, Figs. 1 and 6, carried by the beam transversely to the machine axis, drives the wheel 38 through a worm 37, and the voltage applied to the motor may be varied to adjust the gripping pressure of the jaws on the work. The shaft 30 is moved axially to engage dogs 40 thereon with recesses 41 on the nut 19 by means of a yoke 42 carried by a rod 44 and actuated by a cam-operated lever 45, a spring 46 being provided to allow the dogs to engage the recesses. The recesses are wider than the dogs so that the motor may speed up before encountering resistance and impart a blow to the nut 19. The screw and nut 17, 19 ensure the jaws maintaining their grip on the work during machining. The motor 32 is controlled by push buttons and the work pieces are renewed in the stationary chuck by hand. The position in the turret at which a chuck is opened may be varied by bringing the shaft 30 opposite different work-spindles 12 by changing the bracket 31.