GB908844A - Improvements in devices for the remote control of exactly determined movements - Google Patents

Abstract

908,844. Electric selective signalling systems. VYZKUMNY USTAV OBRABECICH STROJU A OBRABENI PRAHA. Sept. 28, 1960 [Sept. 29, 1959], No. 33341/60. Class 40 (1). A device for producing a discretely variable linear displacement comprises a system of gauges in series, each of which comprises an electromagnet 4 and two relatively movable parts 1, 2 in the magnetic circuit of the electromagnet, the parts 1, 2 being moved a predetermined distance relative to each other when the electromagnet 4 is energized. In one embodiment, when the electromagnet 4 is de-energized, Fig. 5a, a controlled part 57 is urged against part 2 by a spring 58, part 2 coming to rest with distance bolts 55 abutting against a fixed surface. Part 1 is slidable in a non-magnetic tube 53, and when electromagnet 4 is energized, Fig. 5b, parts 1, 2 are attracted together, part 1 moves to the right, arid a distance bolt 56 on part 1 protrudes through a hole in part 2 to move part 57 a predetermined distance equal to the difference in the axial lengths of bolt 56 and part 2. In another embodiment, Fig. 4 (not shown), part 1 is fixed and has an extension which protrudes into a cavity formed in part 2. Part 2 is normally urged away from part 1 by a spring in tension, the electromagnet, when energized, attracting parts 1, 2 towards each other against the tension of the spring. In another embodiment, Fig. 3 (not shown), the electromagnet attracts parts 1, 2 together against the pressure of a compressed spring.