GB1028969A - Improvements in electromagnetic relays - Google Patents

Abstract

1,028,969. Electromagnetic relays. GENERAL RAILWAY SIGNAL GO. March 8, 1963, No. 9267/63. Heading H2B. One leg 17 of the armature 16 passes through an aperture 11 in one end of core 10 and is urged into pivotal engagement with one edge 23 of the aperture by a spring 30. The spring acts between the armature and a moulded insulating block 24 which is mounted in the aperture 11. A plurality of interfitting wafers 50 are mounted on the block 24 and another block 38 secured to block 24 and are secured together by rivets 49. The wafers 50, Fig. 9, have slots formed therein in which contact springs 54, 60 are mounted. One wall of each slot has a projection 56 which fits in a corresponding notch of its associated contact spring and the other wall has a resilient finger 57 which biases the inserted contact spring against the wall having the projection. Pairs of terminals 46, for each of two coils 15, are electrically connected by a spring 48 and a disc 41 of a material, such as " Thyrite " (Registered Trade Mark), which has a high resistance to low voltages and a low resistance to surge voltages. This arrangement provides a shunt across the operating coils and prevents sparking of the contacts used to energize and de-energize the relay. An insulating frame 63 is mounted on the other end of core 10 and the core and armature pass through an aperture 64 therein. The frame 63 is secured to the core by an arcuate spring 76 which acts between the core and the top of aperture 64. Windows, each containing one blade contact, are formed in the frame and the fixed blades 54 are urged against one edge of the windows by springs 86, 87 which are compressed during insertion. A biasing spring 83 acts between the top of aperture 64 and armature 17. An operating comb 90 is fixed to the armature and actuates change-over contact springs 60. The coil springs 86, 87 may be replaced by lateral extensions of the blade which are bent in a zigzag formation (Fig. 10, not shown), by separately formed zig-zag blades (Fig. 11, not shown) or by a coil spring common to the two fixed blades 54 of a change-over contact set (Fig. 12, not shown).