GB372447A - Improvements in or relating to electric switches for use with electric systems of motor vehicles - Google Patents

Abstract

372,447. Latching switches. BOSCH AKT.-GES., R., 4, Militarstrasse, Stuttgart, Germany. Feb. 25, 1931, No. 5858. Convention date, Feb. 26, 1930. [Class 38 (v).] In a switching arrangement for use in motor vehicles two concentric switching members such as for controlling the lighting and ignition circuits are automatically locked on the withdrawal of a key which, after insertion and partial rotation is automatically coupled to the inner switch member so that on further rotation the circuits controlled by the inner member may be made and broken. As shown in Figs. 1 and 2 the outer annular switching plate 12 for controlling the lighting circuits is adapted to be operated by a handle 13 and the inner switch member 11 for the ignition and horn circuits is secured to a rotatable insulating cylinder 4. In a recess formed in the upper end of the cylinder 4 are secured two keyhole members 6, 7, Figs. 3 and 4, with slots 8, 9 as shown. On insertion of a key 5, Fig. 5, the wards 1c of the key pass downwardly through the slots 8, the lower end of the key depressing a spring-controlled locking bolt 14 having an arm 15 fitted with a guided pin 16 normally engaging semicircular recesses in the adjacent faces of the rotatable switching members. Thus both members are freed for operation and if the key is now rotated through 90‹ the wards 10 slip upwardly into the recesses 9 of the lower disc 7 which are meshed by the upper disc so automatically coupling the ignition &c. switching member to the key. Further rotation of the key causes the movement of the inner switching member. The angle of rotation of the switching members is limited by fixed pins 21 in peripheral slots of the members 11, 12 and each of the contact positions has a locking recess 18, 19 opposite the pin 6 so that both switching members are automatically locked on withdrawal of the key. The fixed switch contacts 22 bear on the lower faces of the switching members 11, 12 and are carried by springy arms attached to terminals spaced around the insulating base 1.