Patent GB-1007485-A (GB)
Title: Variable back gauge travel adjustment means for guillotine type cutting machine
IPC: B26D3/10
Filed: 1964-06-23
Abstract: 1,007,485. Guillotine cutting machines. MIEHLE-GOSS-DEXTER Inc. June 23, 1964 [Sept. 11, 1963], No. 25903/64. Heading B4B. A guillotine machine comprises a back gauge driven by a lead screw and control means for controlling forward and backward movement of the back gauge dependent on the direction of actuation of the lead screw; the control means having programme means, which comprise a rotatably mounted drum driven in synchronism with the lead screw, to effect starting and stopping of the back gauge at predetermined forward and rearward limits. In one embodiment, the variable back gauge travel adjustment is effected by an actuator 57, Fig. 1, comprising limit switches 50, 52, 54, 56 which are actuated by adjustable pins 48 carried in rings 44 on the drum 40, Fig. 2, and secured by wing nuts 46. The drum 40 is driven by a worm 30 in turn driven by a belt or chain 24 from the back gauge lead screw 20. Separate rings are provided to limit the forward and rearward motion of the back gauge respectively, and safety limit switches determine the absolute limits of movement of the gauge. Since the drum is arranged to rotate through less than 360 degrees for a complete cycle, or " channel," of operation, unused switch actuators are moved to the area where they do not contact the switches. Each pair of rings is initially set to determine the limits of movement of the back gauge for each of a number of different cutting cycles, or channels. In a second embodiment, the variable back gauge travel adjustment comprises a magnetic tape, 76, Fig. 4, fastened to a drum 72 on a shaft 73 which is driven in synchronism with the back gauge to co-operate with combined record/playback/erase heads 78, 80, which are sprung on a carriage 86 mounted on a square shaft 82. The shaft carries a roller 88 coacting with dwell areas on a cam 90, to position the heads 78, 80 for operation in respective channels on the tape; the heads 78, 80 respectively limit the forward and rearward travel of the gauge. The cam is indexed by a detent wheel 92 coacting with a roller 98 on a pivoted spring- biased lever 100 and mounted on a shaft 94 which also carries a channel selctor switch 106, Fig. 5. A rotary switch 108 rotatably positioned on the shaft 94 and belt-driven by a motor 96 is actuated by a relay and is in series with the channel selector switch 106. Pulses produced by a capacitor arrangement (not shown) are recorded on the tape 76 by the heads 78, 80 on operation of appropriate switches to provide marks for the forward and rearward units of travel of the gauge, and a D.C. source controlled by other switches is supplied to the heads for erasure of marks. In operation, the guillotine is set manually with the gauge in its front and rear positions, marks being put on the tape by operation of the switches 128, 140 and the tape is programmed in this way for each channel in turn. Thereafter, to use the guillotine automatically the index means 92 is set to a selected channel and the lead screw 20 is energized in accordance with the programme on the magnetic tape by the operation of suitable relay circuits. The selector switch arrangement is positioned at the front of the machine. Specification 904,158 is referred to.