Patent GB-976015-A (GB)
Title: Improvements in means for feeding bar stock to automatic lathes
Inventor: KINGSBURY WILLIAM GEORGE
IPC: B23B13/00
Filed: 1963-01-11
Abstract: 976,015. Lathe details. HYDRO-PNEUMATICS Ltd. Jan. 8, 1964 [Jan. 11, 1963], No. 1349/63. Headings B3B and B3T. [Also in Division B8] A lathe bar feed magazine comprises a plurality of feed tubes each adapted to contain a length of bar stock, the tubes being grouped symmetrically about a common axis and mounted on an indexible carrier, means for indexing the carrier to align each feed tube in succession with the machine collet axis and means for ejecting the bar from the tube into the lathe. The magazine comprises a framework 11 supported on legs 12, and an indexible carrier formed by discs 19-22, fixed on a bar 16, which supports 12 feed tubes. Each tube comprises an inner tube 23 fixed in discs 19, 20, and an outer tube 24, slidable over a tube 23, and in a disc 21. A carrier indexing mechanism, actuated by an air cylinder or na electromagnetic actuator is built into the end 14, so that the feed tubes are indexed successively into alignment with a guide bush 25, which is in alignment with the lathe spindle. A pneumatic cylinder and ram 27 is fixed on the frame 11 and carries strikers 28, 29 for engagement with a collar 30, on the outer tube 24 of the lowermost feed tube, and a similar ram is provided for co-operation with the feed tube which is to be moved into this position. The bush 25 contains a cross-bore, air pipes 34, 35 are flared openings 36. A fitting 38 attached to end 14, supports a warning lamp 40 and a bell or like warning device 41. In operation, after the bar stocks have been loaded into tubes 23 from the end 14, the lowermost bar is gripped by the feed device of the lathe, and after each operation has been completed is fed forward to present a new length of bar. Compressed air is being fed into the pipe 34, but since the bar is in the bush 25, the air stream is deflected through openings 36. When the end of the bar passes out of bush 25, the air enters the pipe 35, actuates a diaphragm in the control box 31, and a switch energizes a counting mechanism. As the magazine is installed at a predetermined position behind the lathe collet, it is known that a particular number of components can be made from the remaining length of bar, and the counter is set so that the machine is stopped when this number is reached. Simultaneously with the energization of the counting device, the ram 27 is withdrawn, and the striker 29 retracts the lowermost tube 24, and the second ram is also retracted. The carrier is indexed, and the new tube 24 is moved to feed the bar into the lathe collet, the bar stop in the machine being simultaneously moved out of its normal position. The stub of the old bar is ejected, and the bar stop is returned to position the new bar and the machining is continued. During the movement of the ram 27 to feed the bar, the second ram also feeds the next bar up to a stop, to establish the correct position of the bar irrespective of its length. If a feed tube is not refilled, and this tube reaches the lowermost position, the mechanism will operate up to the stage at which the tube 24 is fed forward. However, a delay mechanism is actuated at this stage, and if a bar does not stop the air flow in the bush 25 within a predetermined time, the lamp 40 is lit, and the warning device 41 is sounded. Air operated means 34, 35 may be replaced by a photo-electric device, or in a modification, by a pair of insulated metal plates forming a capacitor.