GB770030A - Improvements in or relating to electromagnetic relays - Google Patents

Abstract

770.030. Electromagnetic relays. AUTOMATIC TELEPHONE & ELECTRIC CO., Ltd. Sept. 22, 1954 [Dec. 17, 1953], No. 35126/53. Class 38(5) A relay comprises two groups of contact springs placed one above the other, each group comprising a number of (e.g. six) fixed blade (or wire), contacts 22 moulded in an insulating block 26. The block 26 is located in recesses formed in upper and lower blocks 27, 28 supporting sets of movable wire contact springs 23, 24 biased towards opposite sides of the blades 22. As shown, each blade 22 cooperates on each side with a pair of contacts 23 or 24 to form change-over contacts, but simple make or break contacts may be provided. The pile-up comprising the blocks 26, 27, 28 is held within a U- shaped clamp 35, welded to the magnet yoke 11, by a tapered corrugated spring 32 so as to exert a force which is resisted by the yoke and the top of the clamp. The blades 22,of each group are moulded near their free ends in an insulating block 29, having in each end a hole freely receiving a screw 36, the blocks engaging nuts on the screws under the downward bias of the blocks whereby the bolt heads are held against the yoke 11 and the position of the blades may be altered by adjusting the nuts. Slots an upper and lower ribs 30, 31 on the blocks 29 guide the springs 23, 24. The armature 13 controls a frame 39 supported and biased downwardly by limbs 37, 38 ,of a U-shaped spring 33 mounted in the contact pileup. Four insulating rods 40, 41 extending across the frame operate, respectively, the four sets of springs 23, 24, the rods 41 holding the contacts 24 open when the relay is not energized and the frame 39 being raised on energization of the coil 10 so that rods 40 open the contacts 23. A sequential operation of the contacts may be obtained by giving the rods 40. 41 parts of different diameters (Figs. 6, 7, not shown). In two modified arrangements of mounting the contact pile-up (Figs. 3-5, not shown) an upstanding arm is welded on each side of the yoke 11 at the sides of the pile-up and the tops of the arms are joined by a U-shaped clip which is placed over the top of the pileup, tongues on the clip locking with cutout portions in the arms. In one modification the clamping pressure is provided by a downwardly-bowed portion formed in the bight of the clip, and in the other modification by a screw threaded into a plate positioned beneath the bight and engaging the top of the pile-up.