GB896835A - Automatic rod or bar-stock feed device for automatic lathes - Google Patents

Abstract

896,835. Automatic lathes. HAHN, E. Nov. 18, 1958 [Jan. 10, 1958], No. 37053/58. Class 83 (3). An automatic device for feeding stock bars in automatic lathes comprises a magazine of stockbars from which a bar is released to a guide when the preceding bar has been used to a predetermined extent. The stock magazine for the automatic feed is supported on a box-girder 20, Fig. 1 and 4, carried by uprights 25. Stock-bars 37 are supported on a guide 32 so that the lowermost rests on a block 58, Fig. 4. The block forms part of a lever 45 which includes a cover 51 for stock-supporting parts 50. The lever is tilted to open up the stock support and allow the lowermost bar to drop into position, by a member 88, Fig. 3, carried by a further lever 80, which bears against a member 89 secured to the shaft 48 carrying the lever 45. The cover is subsequently closed by a spring plunger 55, Fig. 4, pressing on the cranked end 52 of the lever 45. The stock-bar is fed along the guide channel by a feed block 76, Fig. 3, which is attached to an endless chain 70 passing over sprocket wheels 71, 72, at the rear and forward ends respectively, of the feed device. The spindle to which wheel 71 is fixed is driven through a slipping clutch 114 from a reversible electric motor 110. A second endless chain 95 is driven from the same source through an electromagnetic clutch 121 and this carries a stop device 98 for operating control switches 102, 103. The automatic lathe has a control shaft 16, Fig. 1, which is driven from a shaft 21 through an electromagnetic control 23. The shaft 16 carries cams for the usual reciprocating gripper and chuck-closing motions. A stock-stop 15 is also operated under electric control. Operation. When the end of the bar in the lathe spindle passes a feeler member 130, Figs. 7 and 8, this drops down and operates a switch 138 thus initiating the supply of a fresh stock-bar from the magazine and feed by the sprocket-chain feed-block. The forward end of the new bar contacts the feeler member 130 and slides it along against a spring 134 so that instead of switch 138 being closed a switch 140 is operated. The latter operates an electromagnet 142 to return the member 130 and its supporting lever to the raised position out-ofalignment with the bar-stock. The new stockbar is fed on until it contacts the old bar. The forward movement of sprocket chain 95 initiated by switch 140 brings the stop 93 into contact with switches 102, 103 which control the operation of the lathe so that after the last workpiece is completed from the old bar the waste end is ejected and the new bar faced to begin a new set of workpieces.