GB694363A - Improvements in electrical control magnets - Google Patents

Abstract

694,363. Electromagnetic relays. VIGREN, S. D., BROBERG, W. O. W., and ZANDER, R. A. Feb. 15, 1950 [Feb. 16,1949; Nov. 9, 1949; Nov. 11, 1949], No. 3924/50. Class 38 (v) In a relay having an E-shaped core or yoke with a winding 10 on the middle limb of the E and an armature adapted to bridge the gap between the central and outer legs the armature is pivoted about an axis that is comparatively near to the actual bridging portion of the armature. The arrangement produces a relatively low "pick-up" current. In the form shown in Fig. 5, the armature 9 is a U-shaped member the legs of which are short and pivot on the legs of the E-shaped core being held in position by angle pieces 17, a resilient wire bow 18 and a bow 20. Plates 14 of magnetic material are arranged on the centre limb of the core so that the cross-sectional area of this will be of the same order as the total cross-sectional areas of the legs. The armature actuates studs 25 which actuate contact-spring sets arranged on the two side limbs of the E-shaped core. In a modification, Figs. 9-16 (not shown) the pivoted armature is attached to an end plate of the magnet winding and winding and armature may be bodily adjustable along the core. In other modifications the legs and side limbs of the core are in different planes. The armature may also pivot on the central instead of on the side limbs of the core. It may also pivot about an axis lying outside its own plane. Fig. 20 shows a modification in which the armature pivots about the extreme end portions of the yoke. There may also be arrangements in which the armature becomes more or less saturated during operation so that the centre of attractive force shifts relative to the armature axis during operation.