GB890915A - Improvements relating to electromagnetic relays - Google Patents

Abstract

890,915. Electromagnetic relays. WESTINGHOUSE AIR BRAKE CO. Dot. 29, 1958 [Oct. 29, 1957], No. 34683/58. Class 38 (5). The contact stack of a relay has a single fixing bolt passing through aligned apertures in the insulating wafers between the contact springs and is arranged so that the bolt only need be loosened for removal or replacement of a spring. As shown, the bolt 77 passes through a spring washer 79, a pressure-plate 81, between returnsprings 37, and through an insulator 82 and the wafers 85 which retain between them contactsprings 42, 43, 46 (not shown) on both sides of the bolt. The bolt also passes through an insulating moulding 23 and screws into the rear portion 17 of an E-shaped core having the coil 11 on its centre limb 14. Each wafer 85 has projections 87 and recesses 89 for location with each other and the moulding 23 is recessed at 90 to receive the projectors 87 of the bottom wafer. The wafers are also recessed at 86 (Fig. 6) so that each spring is gripped in two areas a and b or c and d whilst it is located by arcuate notches 91 engaging the sides of the projections 87. A flat spring 30 clamped between the portion 17 and moulding 23 has two parallel limbs which are secured to the ends of a U-shaped armature 27 having its limbs 27a overlying the outer limbs 13, 15 of the core and its blight across the ends of the limbs 13, 14, 15. The armature 27 fits in slots 35 in a contact actuating ladder 45; movement is limited by the engagement of its end against the upper and lower surfaces 60 and 61 of a rectangular slot in a support-plate 50 carrying the ladder 49 supporting the fixed contacts 42, 44. The latter are biased downward and hold the plate 50 against an insulating plate 63 with projections 67 engaging in slots. An angle-section spacer 68 may be inserted with parts 70 between the plates 50 and 63 to set the positions of the armature 37 and ladder 49. The relay may be mounted on parallel bars 96 with a screw 97 in a clamp 98 entering a threaded part 99 in the moulding 23 which also has flanges 95 for engaging the bars 96.