GB579542A - Improvements in or relating to electric snap action switches of the multiple circuit controlling type - Google Patents

Abstract

579,542. Snap-action switches ; retractive switches. IGRANIC ELECTRIC CO., Ltd. May 24, 1944, No. 10058. Convention date, May 26, 1943. [Class 38 (v)] A multiple-circuit snap-action switch structure has a fixed common terminal block 16 disposed in a depression at the bottom of a case 10 with contacts 26 on three of its vertical faces and a cylindrical extension 17 passing through a boss 19 in the bottom of the case 10, this extension being internally threaded to receive a terminal screw and passing through a terminal plate 25. In each recess 12, 13, 14 in the case 10 each house a switch mechanism consisting of a sheet metal member 28 having a terminal hole 29 at its lower end and disposed against the wall of the recess which is slightly enlarged at its upper end by slots 32, 33 in which rest lugs 34, 35 on member 28. An insulating lever 41, having an integral metal member 42, carries a pivot pin 40 for two lugs 38, 39 on member 28, the ends of the pin being flush with the outer surfaces of the lugs. An extension of member 42 has a rounded head 44 which acts in a metal cap 45 seated on a spring 46. A second pivot pin 48, the ends of which abut against the inner surfaces of lugs 38, 39, passes through the lever 41 and carries the flared, hooked ends 54, 55 of a contactor 49 having a channel-shaped lower end carrying a contact 26, preferably of silver, co-operating with its fixed contact 26. The lower end of the spring 46 rests on a cross-piece 50 of the contactor 49. A notch 56 in lever 41 receives, in operation, the arm 92 of a member 88 attached to the handle 61 by extension 85, and, in the open position, the lever abuts against part 59 of the plate 28. The handle 61, which only differs from handle 60 by having a luminous top, has a spherical enlargement 65 having a cross-passage 66 carrying supporting shaft 67. This enlargement is arranged in a metal bushing 68 attached to the cover 69 which is fixed to the spacing member 77 and the case 10 by rods 94 internally threaded to receive attachment screws. The cover 73 has three slots allowing movement of the handle to any of its operating positions. The handle is pivoted to the bushing 68 by pin 80 passing transversely through shaft 67 and resting in openings 78, 79 in the bushing. The enlargement 65 has arcuate slots 82, 83 to provide clearance for movement of the handle about its pivots. An inverted cone-shape spring 93 placed between the member 88 and the cover 69 biases the handle to its central " off position. A leaf spring 95 is arranged in the enlargement 31 of recess 14 to provide a tight fit of the switch unit. The switch unit of recess 12 or 13 may have a longer pivot pin 96 carrying torsion springs 97a, 97b, which bias the springs 46 open, thereby providing a retractive contact arrangement. The switch may be modified for use with two or four sets of contacts.