GB269646A - Improvements in or relating to electrical voltage relays adapted for use with alternating or other fluctuating current - Google Patents

Abstract

269,646. Igranic Electric Co., Ltd., Spaink, J. H. Abbink-, and Taylor, J. R. Jan. 19, 1926. Alternating-current relays; contacts.-A voltage relay for use with A.C. has two coils supplied with currents in quadrature so as to prevent chattering, and the armature unit is flexibly supported. Two relays are shown in Fig. 1, mounted on a common base. Each comprises a pair of plungers 7 connected by a tie rod 8 and supported within coils 4 by a spring 9 anchored to a pin 12. The tension of the spring 9 is adjusted by a screw 16 engaging a nut 18 so that a bellcrank lever 15 can be turned about its pivot 15a to depress the pin 12 against the action of a strong spring 13. The movable contact 3 of each relay is carried by an arm 5 and a flexible strip 6, vertical and horizontal adjustment being secured by a screw 11 adjusted in slots in both the arm 5 and the tie rod 8. thus causing the strip 6 to support the armature unit against horizontal movement. The fixed contact 2 is adjustable by screws 2<a>, 2<b>. The connections are shown in Fig. 3, wherein the upper coils 4 are connected in series with a resistance 24 and the lower coils in series with a choke 27, the whole being connected across the supply through coarse and fine rheostats 5, 26. Opening of the contacts 2, 3 due to rise in voltage remove a short circuit from the coil 2 of a dash-pot retarded relay 19 which thereupon slowly rises to complete a control circuit across contacts 20. A single voltage relay is shown in Fig. 4, the movable contact 35, located between fixed contacts 36, is carried by an oscillatable armature unit 40, 41 suspended by strips 38 from a bridge 39, magnetic plungers 42 supported by the arm 41 extend into the two windings 37 and carry extensions 43 on which are adjusting-weights 44, 45. The fixed contacts 36 are carried on the ends of rods 53 screwed into a frame 50 supported symmetrically on ports 49, springs 55 take up any slack when the rods 53 are turned for adjusting the position of the contacts 36. Temperature variations of lengths of the various parts are compensated. The rods 47 supporting the bridge 39 are such that their upward expansion neutralises the downward expansion of the part 40. The coils 37 are supported on arms 37a projecting from pillars 48 so that they remain in the same relative positions to the plungers 42. The weights 44, 45 are secured by their outer faces to the extensions 43 so that variation in distance apart of the weights is compensated for by the change in the position of their centres of gravity relatively to the extensions, and the symmetrically mounted frame 50 ensures that the contacts remain in the same relative positions.