GB593336A - Improvements in magnetic circuit and coil arrangements for electric vibrators, relays and the like - Google Patents

Abstract

593,336. Electromagnetic interrupters. PLESSEY CO., Ltd. June 15, 1945, No. 15246. Convention date, June 16, 1944. [Class 38(v)] [Also in Groups XXXV and XXXVIII] In a vibrator or relay in which an armature is situated in a constant magnetic field and is deflected by a second field produced by an energized coil the constant field is produced by a coil surrounding the two ends of an iron core and supplied with continuous current. The two coils are placed with their central openings in alignment, the armature extending into the two openings. Fig. 3 shows a vibrator in which a reed armature 39 carrying contacts 58, 59 is supported on a bolt 51 which also supports fixed contacts 60, 61. The armature extends into the openings of two coils 35, 36 the latter of which constitutes the driving coil to deflect the armature. Coil 35 encloses two pole pieces 62, 63 on the ends of an iron core comprising strips 33, 40 connected together at 41, the strip 33 being extended at 34 to constitute the support for the bolt 51. To maintain the armature in vibration a continuous current is supplied from a source 20 to the coil 35 as shown in Fig. 2, one pole of the source being also connected to the armature 39 and the other pole to the ends of the coil 36. The connection to the coil may be made through the centre tapped primary 18 of a transformer and the alternating current obtained in the secondary winding may be rectified by synchronous contacts operated by the armature. The apparatus may be used in indicator or annunciators, a visible signal being given by a disc attached to the end of the armature.