GB913392A - Electric circuit breaker - Google Patents

Abstract

913,392. Automatic circuit-breakers. WESTINGHOUSE ELECTRIC CORPORATION. Jan. 19, 1961 [March 2, 1960], No. 2216/61. Class 38 (5). The trip device of a multi - pole circuit-breaker is mounted in a moulded insulating enclosure comprising a base and cover, each having integral projecting partitions having their edges shaped and arranged to co-operate so as to form a partition wall and seal off the areas on opposite sides of the wall. As shown in Fig. 1, a moulded case circuit-breaker has contacts 21, 23 connected between terminals 15, 17, a toggle linkage 57, 59 operable by a handle 71 and releasable by a cradle 63 normally held by the tripping mechanism and a tie-bar 37 which supports the moving contact arms 35 of all three phases. The trip device 29 is enclosed in the base 81 and cover 89 through which the phase conductors 41 pass as shown in Fig. 4. The base 81 (Fig. 6), has partitions 203 having edges with three faces 215, 216, 217 which mate with faces 225, 226, 227 of the partition 219 of the cover 89 (Fig. 9), to divide the enclosure into three phase compartments. The base 81 has openings 197, 199 for the latch 117 which normally holds the cradle 63 and for two arm members 201 in which pivot-pins in the trip bar 107 engage. The bar 107 extends through openings formed by corresponding semi-circular recesses in the partitions 203, 219 and flanges 228 on the bar 107 close the openings. Armatures 133 can be adjusted by rotation of a member 157 to move a cam 155 which acts on a follower 147 controlling the air gap between the armature 133 and core 129. A screw connection between the parts 171, 173 of the follower 147 allows for adjustment during assembly and it may be cemented after adjustment. Gaps 206 in the partitions allow access to armature biasing springs 140 during assembly and are closed by insulating plates 229.