Patent GB-1050965-A (GB)
IPC: B23B13/00
Abstract: 1,050,965. Feeding bar-Stock. USINES TORNOS, FABRIQUE DE MACHINES MOUTIER S.A. July 9, 1963 [July 10, 1962], No. 27046/63. Headings B3B and B3T. An automatic sliding-headstock lathe for machining bar-stock 9 comprises means for removing automatically the waste end of the bar-stock. End-working drills, taps, dies or punches (not shown) may be carried in a slide, yoke or turret controlled by a cam-shaft 34. A pair of radial tool-slides 48, operated by levers 49 from the cam-shaft, are carried by a yoke 45 mounted on a pivot 46 close to a centre rest 39 carried by an adjustable, conical sleeve 41. The spindle-collet 8 is opened by a spring 11 when a ring 19 is moved towards the collet, allowing the ends 18 of closing levers 13 to move apart. A yoke 20 for operating the ring 19 is connected by a pin 25 to a lever 27 pivoted at 28 to the lathebed 1. Lugs 35, 36 on the cam-shaft 34 operate the lever 27, through abutments 31, 32, and an electromagnet 68 co-operates with a further abutment 60 on the lever. The lathe is supplied with bar-stock from the tubes 53 of a drummagazine 52 which is indexed by a weight 66, the stock being fed by pushers 51 moved by a chain 55 driven by a continuously energized motor. A known hooking device 54, 58, 59 connects the chain to the operative pusher, which is advanced and withdrawn by the chain, the chain abutment 59 also initiating the indexing operation The pusher holds the bar-stock against the parting-off tool 50 during rearward movement of the headstock 2, the tool also locating the end of a new stock-bar. The camshaft is stopped and the collet opened during ejection of the waste-end and indexing of the magazine. This is controlled electrically by operation of contacts 78, 84, 85, 88 by the chainabutment 59. A screw 61 with a spring-loaded pin 98, Fig. 3 (not shown), for pushing the wasteend out of the back of the spindle, is mounted on the turret &c. in front of the spindle and driven endwise by a toothed nut 114 rotated by a chain and an electromotor 62. A catch 117 holds the end 102 of the pin 98 during the first part of an ejecting stroke of the screw 61, loading the pin until an abutment 108 on the screw releases the catch, the pin being retained in the extended condition by a spring-loaded catch 100. This i released, by contact between a lever 109 and a fixed abutment 113, after the nose 99 of the screw has pushed the waste-end through the centre-nest 39, the pin completing the ejection. Operation and electrical control.-As the headstock advances followed by the pusher 51 during the machining of the last workpiece before the waste-end, the chain abutment 59 closes contact 78 which energizes a relay 75 controlling contacts 79, 80. The cam-shaft continues to rotate until a cam 70 closes contacts 72, 73, which energize an electromagnetic clutch 67 and electromagnet 68, interrupting the drive to the cam-shaft and opening the collet. The abutment 59 moves round the pulley 57, and on its rearward stroke closes contact 88 which energizes a relay 86 controlling contacts 89, 91 and starts the ejector motor 62. This moves the screw 61 towards the headstock, closing a holding-circuit contact 90 operated by the screw. After the ejection operation, the ejector screw 61 operates a reverse switch 64 for the motor 62, effecting return of the screw to its start position in which it again operates the reverse-switch 64 and opens contact 90 to stop the motor. When the chain-abutment 59 on its rearward stroke operates contact 85, a relay 76 is energized and relay 75 de-energized, deenergizing the electromagnet 68 and the clutch 67 to re-engaging the cam-shaft drive and closing the collet. The cam-shaft drive is again interrupted and the collet opened when a cam 71 closes a contact 74, this condition remaining until the chain-abutment, advancing along the upper chain-strand, opens contact 84 before the new stock-bar engages the tool 50. The opening of relay 76 is delayed until the stock-bar contacts the tool. The contacts 72- 74 operated by cams 70, 71 are effected to operate the clutch and electromagnet only after contact 78 has been operated during machining of the last workpiece on a bar. The magazine may be re-charged with stock at one of the magazine positions out of alignment with the lathe-spindle. In a modification, Fig. 6 (not shown), the waste-end is withdrawn through the front of the spindle by jaws 123 on a tube 130 within the screw 136, which is moved endwise, as in the first construction, by a nut 142, the contact 78 being placed so that the pusher projects the waste-end slightly beyond the collet before the pusher is withdrawn. The jaws are opened by springs 143 and pass over the waste-end before the tube 130 is stopped by a collar 144, an ejecting pin 131 engaging the waste-end being loaded by a spring 132 as the tube 130 advances. Further advance of the screw causes its end 137 to rock levers 126 and close the jaws 123 on to waste end, which is withdrawn until further rearward movement of the tube is prevented by an abutment 147. Continued movement of the screw releases the jaws 123, and the waste-end is ejected by the pin 131. Instead of the control described, an hydraulic, pneumatic, mechanical or electronic control may be used.