GB778075A - Improvements in or relating to copying lathes - Google Patents

Abstract

778,075. Copy-turning. DRUMMOND BROS., Ltd. May 5, 1955 [May 28, 1954], No. 15929/54. Class 83 (3). A slide arrangement for a copying-lathe comprises a saddle 1, Fig. 2, movable along the lathe-bed, and a base 2 on the saddle carrying superimposed cross-slides 3, 4, the latter mounting a tool-post 5. Slide 3 is fed transversely of the latheaxis by an electric-motor 8, Fig. 1, secured to the saddle and driving a worm 10 meshing with a wheel 11', Fig. 2, keyed to a nut 13 rotatable in bearings 14, 15 fixed to base 2. The nut engages a screwed-rod 20 held against rotation by a pinch-bolt 26A and secured, between a shoulder 23 and a nut 26, to slide 3. Back-lash between the rod 20 and nut 13 is removable by adjusting and locking a further nut 19 engaging the rod. An extension of the rod is engaged by a nut 27 rotatable in bearings 28, 29 on slide 4 by a hand wheel 31. Mounted on slide 4 is a drum 42, Fig. 1, having stop-members 43 positionable to co-operate with a stop 44 on slide 3, and slide 4 is moved by hand wheel 31 relative to slide 3 to abut one of the stop-members 43 against stop 44 to set the depth-of-cut of tool 6. A tracer is secured by a clamp 45 to slide 3. The tool is fed to the work, and the tracer to the pattern, by motor 8, and slide 3 drives, by a rack 33 and pinions 34, 35, a drum 36 having cams 37, 38, the latter cam actuating a switch 40, when the tool is near to the work, to reduce the feed speed. When the tracer engages the pattern it controls motor 8 and a further motor which effects longitudinal movement of the saddle. After a predetermined movement, the saddle actuates a switch which stops the longitudinal feed and causes motor 8 to withdraw slide 3 until switch 41 is actuated by cam 37 to stop the motor.