Patent GB-904158-A (GB)
Title: Magnetic tape control systems for guillotine type cutting machines
IPC: G05B19/16
Filed: 1960-07-18
Abstract: 904,158. Guillotine cutting - machines. MIEHLE-GOSS-DEXTER Inc. July 18, 1960 [Sept. 16, 1959], No. 24968/60. Class 31 (1). A guillotine cutting-machine comprising a work table and a back gauge for moving a stack of sheets thereacross with a programmed series of stop positions along the work-table is characterized by drive means for the back gauge, transport means for moving a magnetic tape in synchronism with the back gauge, and electrical means responsive to control signals along the magnetic tape for controlling the back gauge drive means to successively stop the back gauge at the programmed positions. A back gauge 105, Fig. 5, is traversed longitudinally of a work table 100 by means of a rotatable feed screw 112 which is driven by a high or low-speed motor 140, 145 associated with electromagnetic clutches 161, 160, respectively, the clutches being coupled selectively to drive the feed-screw at high or low speed. A magnetic tape 200 has sprocket holes engaged with a sprocket drum 205 which is attached to the feed screw so as to be driven in synchronism therewith. The tape, Fig. 6, comprises two tracks A, B, the track A being impressed with " stop " signals, e.g. 215a to 218a, and the track B with " slow " areas, e.g. 250, 251. The " stop " signals and " slow " areas are so arranged that when the tape is moved forwardly past magnetic heads 210, 211, a " slow " relay 257a, Fig. 7A, is energized to de-energize clutch 161 and energize clutch 160 and drive the back gauge at a slow speed just prior to the programmed positions and a " stop " relay 239a is then energized to de-energize both clutches and stop the back gauge at the programmed positions. The tape comprises several individual programmes which are selected by moving the magnetic heads transversely of the tape. The " stop " signals are recorded on track A of the tape by means of a system comprising photo-electric means 220, Fig. 6, for scanning a template 212 marked with a programme of back gauge stop positions 215 to 218 and movable with the back gauge, an amplifier 231 for conducting pulse signals 215a to 218a to magnetic head 210, and a control switch 235 which is moved to recording position. Instead of scanning a template, the printed top sheet of the pile to be cut may be scanned. The " stop " signals may, alternatively, be recorded manually. For recording the " slow " areas on track B of the tape, the template is removed and the back gauge and tape moved in the reverse direction after the switch 235 has been moved to the reading position and a control switch 240 moved to the recording position. Whenever a " stop " pulse signal such as 216a passes head 210, the read pulse is amplified at 237 and impressed on time-delay unit 245 which after a certain time actuates an electronic gate 246 to send signals from an oscillator 276 into an amplifier 242. These amplified signals at oscillator frequency are impressed on head 211 during the time that unit 245 is active. Extended " slow " areas such as area #<SP>1</SP> of area # in signal 251 may be incorporated to take care of trim-out operations. In modifications, Figs. 8 and 9 (not shown), the " slow " and " stop " signals are recorded on a single track of the tape using a single magnetic head. In further modifications, Figs. 10 and 11 (not shown), the " slow " and " stop " signals are recorded on two tracks of the tape by means of three or four magnetic heads and in these modifications, the time-delay unit (245) is omitted. Specification 847,932 is referred to.