GB660699A - Improvements relating to capstan lathes - Google Patents

Abstract

660,699. Lathes; tapping. HERBERT, Ltd., A., and LLOYD, A. H. Feb. 15, 1950 [March 18, 1949], No. 7409/49. Class 83 (iii). A capstan lathe is provided with a switch mounted on the headstock which each time it is operated may effect a change of speed or reversal of the lathe spindle, rods or other projections extending from the turret faces being adapted selectively to operate the switch at a requisite moment during the turret advance. A micro-switch 14, Fig. 1, mounted on the lathe headstock II may by successive impulses be arranged to control either a two-speed motor or a reversible motor for the lathe spindle. Actuation of the switch is effected through the bevelled end 15 of a slidable spring-returned rod 16, also carried on the headstock, and in alignment with a number of rods 21 of different length associated one with each of the turret faces. The rod 16, Fig 1, is shown with an extension 22 fitted to its outer end. Automatic reversal of the spindle assists in returning the turret when a comparatively large tap 24 is used. When using a small tap 27, Figs. 5 and 6, however, breakage of the tap might result from such a practice and in this case the tap is slidably held against rotation between two springs 29 and 30, Fig. 6, in a sleeve member 31. Spring 29 is stronger than spring 30 and spring 17, Fig. 1, for the switch rod. The switch-actuating rod 34 in this case is carried by the tap-holding member 28 and not directly by the turret. A speed-controlling switch and a reversing switch may be carried on the headstock, both operated in the manner described above or the speed changing may be effected as described in Specification 481,895, which is referred to.