GB551433A - Improvements in electromagnetic relays - Google Patents

Abstract

551,433. Relay selectors. WESTERN ELECTRIC CO., Inc. May 27, 1942. No. 7161. Convention date, April 19, 1941. [Class 40 (iv)] [Also in Group XXXVII] An electromagnetic relay adapted to effect an economy in the number of contact springs, soldered connections and coils necessary to achieve certain ends, comprises a reed armature 6 arranged between magnetic laminations acting as pole pieces with interposed insulating laminations. In the form shown in Figs. 1 and 4, the reed 6 is arranged between two poles 1 and 3 on one side and a pole 2 on the other and a coil L surrounds the poles 1 and 2 and a coil R surrounds the pole 3. The reed 6 is biased downwards into the position shown in Fig. 4. If R is energized the armature moves up to complete circuit f b and break circuit a f. Subsequent energization of L produces no further effect and the armature will remain in its upper position if either R or L is then de-energized. If from the position shown L is energized and then R, nothing happens. Fig. 12 shows an arrangement for counting impulses in a circuit 79, 80. Three impulses can be counted and each lights a lamp 82 or 84 or 86. A coil L surrounds a number of fixed cores and two oppositely arranged coils R<SP>1</SP>, R<SP>2</SP> surround other cores. Each reed armature 72, 73, 74 &c. carries a projection 47 which bears on the armature below. Switches 48, 50 are first closed and relay 80 operates to remove a short circuit across coils L, R<SP>2</SP>. All three coils are thus energized in series but coils R<SP>1</SP>, R<SP>2</SP> oppose each other and produce no magnetic effect. Disc 79 now breaks the circuit 80 say the first of three times, causing L and R<SP>2</SP> to be short circuited so that R<SP>2</SP> alone exerts a magnetic force. Armature 72 is attracted. When the " break " impulse has ceased coil L attracts armature 73 and closes circuit to lamp 82. The next impulse causes armature 74 to move up, and then armature 75 and lamp 84 to be lighted and so on.