Patent GB-605260-A (GB)
Title: Improvements in lathes and like machine tools
IPC: B23Q5/00
Filed: 1944-09-21
Abstract: 605,260. Lathes. LODGE & SHIPLEY MACHINE TOOL CO. Sept. 21, 1944, No. 18050. Convention date, Sept. 28, 1943. [Class 83 (iii)] A lathe or like machine tool provided with main and auxiliary spindles rotatable independently of each other, is characterised in that a support for the spindle drive pulley is so arranged with respect to the main spindle that upon relative axial movement of the main and auxiliary spindles access is provided to the drive pulley from a location between the separate spindles. The lathe spindle is driven by V-belts 41, Fig. 1, from a prime mover 39 which may be electric or hydraulic and includes control means for a stepless speed range. The belts are maintained at correct tension by a slidable jockey pulley or drum 240, Fig. 8, which is adjusted by a screwed rod 351. The spindle, Fig. 6, is in two parts, which are coaxial-a main part 59 and an auxiliary part 60. These parts are shown separated in the drawing which is the position obtained when belt-changing is necessary, the operative or normal driving position provides a dog-tooth engagement of the inner ends of the spindles at 93. Disengagement is effected by releasing securing bolts in the holes 100, which retains a sleeve carrying the auxiliary spindle, and withdrawing the sleeve rearwardly in the framing to provide a sufficient gap between the spindle ends for belt changing. The headstock is divided into three compartments for housing the spindle parts, a clear gap being provided between middle and rear compartments so that the belts may be slipped through and placed into or out of driving engagement with the pulley 38. Headstock driving-gear.-The V-drive pulley 38, Fig. 6, is carried in bearings in the headstock frame and is keyed to a sleeve-piece 61 which has a splined forward end. A sleeve 65 operated by a lever on the headstock slides along' the splines and carries an integral gearwheel which may be selectively brought into mesh with either the back gear-wheel 69 or with an internally toothed ring 65 secured to a gear block 68 which is keyed to the main spindle 59; the latter arrangement thus giving a direct drive from pulley to spindle. The back gear drive includes a slidable gear 72 which enables two speeds to be obtained through this drive. The auxiliary spindle 60 is provided with gear teeth 103, 104 the latter drives an oil pump 105 for lubricating the headstock bearings, while the former, through an intermediate wheel 109, drives the feed train and lead screw, 37, Fig. 1. The wheel 109, Fig. 6, is carried by a sleeve 101. which may be moved to disengage the wheel 109 from the spindle drive by a rack and pinion 311, 312. Speed-controlling mechanism.-The spindle speed may be varied by means of a hand wheel 44 on the headstock which controls a rheostat, or a fluid control device, where a hydraulic prime mover is employed. This hand wheel is coupled by bevel gears and a square shaft 201, Figs. 1 and 8, to a further remote control wheel 45 mounted on the tool carriage 34. Coupled control levers 42 and 43 are similarly mounted on the headstock and carriage respectively, to start and stop the prime mover 39. Indexing.-Movement of the feed train driving gear 109, Fig. 6, to the right, when the main and auxiliary spindles are connected for operation of the machine, disengages the feed drive and the wheel 109 is engaged with a stationary detent which locks the feed train against rotation (not shown). The machine spindle may then be indexed independently of the feed train by means of a tommy bar inserted in the holes 122. Index graduations being visible on the sleeve 111 carried by the spindle through a slot 112 in the spindle housing. The Specification as open to inspection under Sect. 91 includes the following subject-matter: Speed - indicating mechanism.-Indicating means may be provided on the headstock for showing the cutting speed and comprises a dial 149, Fig. 10 (Cancelled), indicating the cutting speed and an adjusting device 154 for setting the indicator to the diameter of work being turned. The main gear pulley 68, fastened to the lathe spindle as described above, has an inclined face against which a spring-pressed friction pulley 127 engages. The pulley drives a disc 733 across the upper surface of which a further friction wheel 138 is adapted to be traversed. This wheel is carried in antifriction bearings 140 housed in a bracket 141 which has screw-threaded connections with the rod 142. The latter through gearing 166, 165 a spiral wheel and further spur gears, is rotated by the adjusting device for the work diameter. The pointer 151 for cutting speed indications is driven from the friction wheel 138 and thus correlates the speed of the work spindle with the work diameter set on the indicator. This subject-matter does not appear in the Speci. fication as accepted.