Patent GB-637416-A (GB)
Title: Improvements in electric receiving or switching devices for remote control installations
IPC: H02J13/00
Filed: 1947-12-03
Abstract: 637,416. Actuation of switches. LANDIS & GYR SOC. ANON. Dec. 3, 1947, No. 31962. Convention date, Dec. 10, 1946. [Class 38 (v)] A switching device or " receiver for a remote control installation has a synchronous motor, which when started by an audiofrequency responsive relay, rotates a control shaft through one complete revolution. A further energization of the relay while the shaft is rotating, enables the control shaft and the parts mounted thereon to pivot bodily about a fixed shaft to actuate a selected switch unit. The last part of the revolution of the control shaft is used to load an energy storage spring, the release of which in a subsequent operation of the device opens the switch unit. An audiofrequency impulse superimposed on the lines a, b momentarily energizes relay coil 2 to turn the relay armature 3, which by means of a lever 5 releases a switch latching member 7 to permit the contacts carried by spring blades 8, 12 to close. The synchronousmotor 22 is energized and drives the control shaft 18 through gears 19 ... 21, the contacts on the blades 8, 12 remaining closed, while the shaft 18 makes one revolution, as the end 13 of the blade 12 is freed by the movement of a sector 26 on the shaft 18, to prevent the reopening of the contacts when the lever 5 and member 7 are restored to their initial positions by a spring 6 when the control impulse ceases. The shaft 18 is mounted in a frame 16 which is pivoted on a fixed shaft 17, and the control shaft 18 carries a cam wheel 23 which co-operates with a roller 24 on a fixed shaft 25 to impart an oscillatory movement to the frame 16. This oscillation, or pivoting of the frame 16 about the shaft 17, is normally prevented by the engagement of an extension 55 of the frame with the end of the lever 5. Adjustably fixed to the control shaft 18 are two control discs 27, 28 having pins 29, 30, which if brought into engagement with projection 33 on levers 31, 32 cause the actuation of a switch. This switch comprises a contact 43 on a rigid member 45, a contact 44 on a spring blade 42 which has an insulating abutment 46, and a portion 41 which engages a projection 40 on the lever 32 to hold the contacts open, and a spring blade 39 which is latched in a stressed condition by the lever 31. In the Figure, the contacts 43, 44 are open and to close them, a first impulse is transmitted to the relay 2, 3 which closes contacts 8, 12 to start the motor. At a timed interval afterwards a further impulse is transmitted to the relay and the resulting movement of the lever 5 away from the extension 55 of the frame enables the frame to pivot on the shaft 17 at the instant when the pin 30 is above the projection 33 of the lever 32, so that the downward movement of the pin 30 causes the lever 32 to pivot and release the end of the contact spring 42 which brings the contact 44 into engagement with the contact 43. If the contacts 43, 44 were closed and it is desired to open them, the second impulse is transmitted to the relay at the instant when the pin 29 is above the projection 33 on the lever 31, so that the downward movement of the pin 29 causes the lever 31 to release the spring 39 which springs down and strikes the abutment 46 to open the contacts 43, 44, the blade 42 being latched down by the projection 40 on the lever 32. The spring 39 is again stressed and relatched towards the end of the revolution of the shaft 18 by means of a cam member 52, a lever 50 and an arm 47. Additional control discs 27, 28 and levers 31, 32 may be provided to control selectively additional switch units. Specifications 494,792, [Group XXXVIII], and 633,195 are referred to.