GB1352926A - Multi-pole switch mechanism - Google Patents

Abstract

1352926 Electromagnetic contactors; switch contact units ROWAN CONTROLLER Inc 19 April 1971 [11 Feb 1970] 20934/71 Heading H1N A contactor which may have an odd or even number contact modules symmetrically disposed in relation to an operating member has interengaging locator means 27, 28, 63, 29, 30, 62, 102 which enable each module to be located on a base 25 at discrete positions spaced apart by distances of half the width of a module. The contactor shown has coils 35, 36 surrounding limbs of a U-shaped yoke 39 and a U-shaped armature 19 which is biased away from the yoke 39 by springs 49 and engages the plunger 20 of each contact unit module 17, which has a movable contact member 76 engageable by the surface 91 of the plunger 20 to move the member 76 to open the contacts against the bias of a spring 80. When the armature 19 is in its attracted position the springs 80 urge their respective contact member 76 to engage respective fixed contacts 78 and the member 76 are so arranged with respect to their terminal members 74 as to form a current loop tending to urge the contacts closed under excess current conditions. Each contact unit module 17 is formed with two casing ports 70 riveted together at 71 to retain the contacts and plunger and each has locating projections 28, 30 fitted in recesses 27, 29 in the base 25 of the contactor. The projections 28 are parts of hooks 100 which engage parts 63 of the base 25 which also has parts 62 engaged by spring biased releasable hooks 102 at the other ends of the modules 17. An offset upper leg 93 (Fig. 3) of each plunger 20 extends in a slot 94 of the housing parts 17 and may be engaged by the end (130) of a further plunger 22 which is the operating member of a respective auxiliary contact unit having a reversible movable contact bridge (Figs. 7 and 10, not shown) to provide normally open or normally closed contacts.