GB364584A - Improvements in turning lathes and like machines - Google Patents

Abstract

364,584. Lathes. POTTER, W. W., Pawtucket, Rhode Island, U.S.A. Sept. 3, 1930, No. 26353. Convention date, Oct. 11, 1929. [Class 83 (iii).] In a lathe the work-spindle is carried by antifriction bearings arranged at points along the spindle so that the distance of the workengaging member from the farthest bearing is less than the diameter of said bearing. As applied to a vertical spindle lathe, the headstock centre 13 is mounted in the sleeve of a face-plate 12 which is attached to the spindle 11. The lathe bed 10 carries outer races 14, 18 for ball or roller bearings 16, 21, the inner races 15, 20, being mounted on flanged sleeves 22, 23 on the spindle. A worm 25 drives the spindle 11 through a worm wheel 24 located between the flanges 22, 23 and between the bearings 14, 18. The tailstock centre 44 is mounted in a spindle 30 to which is keyed a disc 39, inner races 33, 36 being secured to the spindle and disc respectively and outer races 32, 35 for the ball or roller bearings 34, 37 being carried by the tailstock 26. The bearings 34, 37 are arranged on a conical surface of substantially the same angle as the centre 44 and said surface may be a continuation of the conical surface of the centre or may lie outside thereof as shown. The disc 39 has a toothed periphery engaging a pinion 39<1> on a shaft 40 driven at 41 from a gear 42 on the headstock spindle 11. The tailstock 26 is slidable as a whole, to position the centre 44, on guide-rods 27 which connect the base 10 to a bracing member 28, adjustment being effected by a screw 29. The work w is driven by a dog 45 on the face-plate 12 and the turning tools 47 are carried by a slide rest 46 slidable on one of the rods 27 and are given the rectangular feed movements shown diagrammatically in Fig. 2. In a modified headstock the outer race 140, Fig. 3, is held in place by a ring 141 provided with a number of layers of cork 48 which rub against the inner race 200. Two rows of balls 210 are located close together axially between the races and a face-plate 120, which carries the centre 130, is secured to the inner race, the latter being toothed at 49 for the drive from a pinion 50. In a further modification which is similar to that shown in Fig. 3, the inner race is stationary and the face-plate is secured to the outer race which carries worm teeth for engagement with a driving worm. In each case the bearings are constructed and assembled so that they have an initial compression.