Patent GB-358727-A (GB)
Title: Improvements in or relating to controlling means for automatic lathes
IPC: B23B7/02
Filed: 1930-10-13
Abstract: 358,727. Lathes. MULKA, F., 38, Rusche Strasse, Lichtenberg, Berlin. Oct. 13, 1930, No. 30617. Convention date, Nov. 22, 1929.' [Class 83 (iii).] The tool slides and other parts of an automatic lathe are controlled by means of two coaxial rings 7, 9 rotatably mounted at the front of the headstock 2, the outer ring 9 rotating continuously in one direction at different speeds and effecting an oscillatory movement of the second control ring 7. A tool slide carrier 5 is mounted on the front of the headstock. The ring 9 is driven in the direction of the arrow a by worm gearing 10, 11 at alternate high and low speeds and is provided with cams 12, 13 which operate the clamping sleeve of the work chuck 15. Cams 16, 26 on the ring 9 effect the speed changes of the ring-driving mechanism. For the slow drive, employed during machining operations, the worm 11 is driven from the spindle through worm gearing 18, change wheels 19, 20, bevel gears 22, 23, 22a, 23a and free-wheel coupling 24. The high speed is obtained by switching on, by means of the cam 26, an electric motor 25, the low speed drive being overrun while the high speed is in operation. The control ring 9 also carries cams 27, 28, the cam 27 acting through a lever 30 and toothed segments 31 to bring a swinging tool holder 32 into working position, while the cam 28 engages a roller 29a to effect the withdrawal of the tool holder 32. The ring 9 is fitted with an abutment 35 which through a pawl 33 imparts motion in the direction of arrow a to the main control ring 7. At a predetermined point a roller 36 on the pawl engages a cam surface 37 to disengage this drive. During the anticlockwise movement a toothed segment 38 engaging a pinion 41 is arrested by a stop 39, and the pinion thus remains stationary until teeth 43 on the outer control ring engage the pinion and move the segment in the direction of the arrow b thus compressing a spring 40. When the pawl 33 is released, the segment imparts clockwise movement to the main control ring, this movement continuing until the teeth 43 pass off the pinion 41 whereupon the main control ring is stopped until the stop 35 picks up the pawl 33 and causes the next anticlockwise rotation. The clockwise movement of the main control ring and part of the anticlockwise movement are effected at the high speed. The main control ring carries a cam ring 8 provided with cams 45 operating cross slides 46, the rollers 47 being carried in slides 48 for adjustment in accordance with the diameter of the work. The cross slides carry broad turning tools 66 and two opposite slides carry parting tools 67 so that one first piece is cut off while the next work-piece is being turned. A pivot 49 carries an arm 52 for transferring finished work-pieces or for feeding them to supplementary devices such as a slitting saw. Before the end of the machining operation this work-transferring arm is moved into operative position by a toothed segment 53. Towards the end of the return (clockwise) movement of the main ring, a segment 55 engages a pinion 56 and positions a stop arm 57 which determines the feed of the stock bar. An arm 59 of the tool-holder 32 engages a groove in a slide 60 which is fed longitudinally by means of a cam 61 to feed the tool longitudinally along the work-piece. A screwcutting tool 62 is moved longitudinally by means of a cam 63 acting through a rackbar 64 and pinion 65.