Patent GB-510006-A (GB)
Title: Improvements in or relating to electric systems for the control of tools or the likein industrial processes
IPC: G05B19/21
Filed: 1937-12-22
Abstract: 510,006. Electric control systems. BERGIER, J., ESKENAZI, A, and GAVRONSKY, V. Dec. 22, 1937, No. 35462. Convention date, Dec. 24, 1936. [Class 40 (i)] In a system for controlling the operations of industrial machines, such as lathes, the controlled part, e.g., a tool, is operated by electric impulses produced by a record of the operation to be carried out, and the movement of the record are controlled by movements of the tool so that the record may be slowed down or stopped when the tool lags behind. The record may be of the film, disc or perforated band type and may be produced from a graph of the movements to be effected by co-ordinating two groups of perforations or other records with the rising and falling parts of the curve; alternatively the record may be produced from calculated values of the movement or directly by electrical impulses generated by movement of the parts to be controlled. A single movement may be recorded in the form of several lines of perforations each line representing displacements of different amplitude in order that coarse and fine control may be effected. Fig. 3 shows a system for controlling the movements of a tool 104 by a perforated record X. The record is provided with two series of perforations which co-operate with brushes e, d to transmit impulses to ratchet mechanisms 2, 4 which respectively control movements of the gear wheel in opposite directions through a differential mechanism a, b. The wheel 7 drives one wheel 9 of a differential 8, having a wheel 10 which is driven by the tool motor 98 and planet wheels which operate a control switch 12 for the driving motor 97 of the record and contacts 99, 100, 101 for the tool motor. The contacts 99, 100, 101, are arranged so that variation in the movement of the wheel 8 relatively to the wheel 10 produces operation of the contacts and the motor 98 until the discrepancy is wiped out. When the tool is moved in synchronism with the record and the wheels 9, 10 rotate at equal speeds, the switch 12 is positioned so that the motor 97 rotates at its normal speed. If the wheel over-runs the wheel 10 by a small amount, the switch 12 operates a relay 91 which slows down the motor 97. If the over-run continues, the switch 12 is operated further to pull up relay 92 and stop the motor 97. The ratchet mechanisms may be replaced by stepby-step electro magnetic motors of the type wherein the impulses are distributed to magnets which operate rotary armatures or control linked reciprocating armatures. When series of perforations representing movements of different degrees are employed, the separate series of impulses operate a corresponding number of contact arms 13, 14, 15, Fig. 4, which co-operate with drums 16, 17, 18 provided with diametral insulating segments. The drums are driven by the motor 22 which performs the necessary operation, the motor circuit being under the control of the drums and brushes and being opened to stop the motor when the insulating segments of all the drums occupy positions corresponding to those of the brushes. The circuit arrangement is such that the motor is reversible, relays 19, 20 also being provided to render the drums operative in succession. A relay 107 also is provided to open the circuit of the record motor 108 during operation of the tool motor 22. In a modification a set of contact drums is provided for each direction of rotation. Instead of employing separate groups of records for producing different movements, a single group capable of producing impulses of variable frequency may be employed; in this system the impulses control one wheel of a differential mechanism, the other wheel of which is driven at constant speed. Several independent controlled shafts may be driven in both directions from a common continuously driven shaft through the intermediary of electro-magnetically controlled roller type friction clutches. When a film is used for the' record, a photo-electric pick-up is employed. The Specification as open to inspection under Sect. 91 describes a single contact drum which is positioned in both axial and rotary directions by separate series of impulses driven from the record. This subject-matter does not appear in the Specification as accepted.