GB878160A - A stepped cyclic programme control device - Google Patents

Abstract

878,160. Machine tool details. EMAIN, J. Feb. 25, 1959 [March 27, 1958], No. 6514/59. Class 83 (3). Means for controlling a series of operations in a machine comprises a plurality of axiallyspaced angularly-settable elements 13 and a plurality of angularly - spaced axially-settable elements 30 on a shaft 21, and stepping means 42 for rotating the shaft to present the elements to sensing stations. The shaft 21 is supported by a centre 24 on a bracket 25. The ratchet 42 is stepped round by an adjustable-stroke lever operated through a chain 57 and a rod 67 by a pneumatic device 69 controlled by an electromagnetically - operated valve 15. The shaft is positioned by a plunger 33 engaging recesses in the disc 29 which carries the elements 30. The cams 13 are screwed to carriers 36 and operate plungers or valves to control machining operations. Instead of, or in addition to, the cams 13, electrical contact discs may be carried by the shaft 21 or a cam 40 for energizing electric motors &c. The elements 30 are adjusted by set-screws 31 and act successively to determine the time for each dwell of the shaft 21. When the shaft is indexed, a weight 93 causes a constant velocity feed of a switch unit 94 under the control of an hydraulic dashpot device having a plate 88 partially covering passages 87 in a piston 86. When a switch-operating lever 95 engages a stop 30, the valve 15 is actuated. The pneumatic device 69 is thus operated to index the shaft 21 and the device 86 is returned to its initial position by an abutment 71 on the ratchet-operating rod 67, the plate 88 then yielding against a spring 89. By omitting one of the pins 30, the machine may be stopped after one rotation of the shaft. In a modification, the constant feed of the switch unit 94, Fig. 8, is provided by a cam 125 which is clutched intermittently to a constantly-rotating shaft.