MACHINE TOOL CONTROL SYSTEM

1,254,446. Machine tool details. SUNDSTRAND CORP. 18 Nov., 1968 [20 Nov., 1967], No. 29061/71. Divided out of 1,254,445. Heading B3B. [Also in Division G3] A control system for a plurality of machine tools capable of selectively performing machine operations on various parts delivered thereto, each part having a process number associated therewith, includes means for assigning to a part which has completed a machining operation a new process number which re-identifies it. As shown, numerically controlled machine tools 20 are supplied with parts 25 on pallets 26 from a common parts storage conveyer 40 in accordance with information on a code-plate 50. The indicia on the code-plate are read by a unit 49 and the information fed to a computer 30 which determines the transfer of a selected part by a rain 44, 45 and the transmission of an appropriate programme to the machine tool 20. On completion of the machining programme the part is transferred to a conveyer 54, by which it is returned to the conveyer 40, past a write head 56 which, in response to signals from the computer, re-identifies the part by new code indicia. Transfer between storage conveyers is effected through conveyers 60, 61 and collisions at intersections are prevented by controlling transfers by gates 137 held closed by the interruption of a light beam 135.