GB159614A - Improvements in electric switches - Google Patents

Abstract

159,614. Jamie, R. C. S. Dec. 3, 1919. Switches; switchboards; cases; contacts. - A series-parallel switch for connecting two sets of electrical appliances such as batteries, lamps, and dynamo-electric machines in series or in parallel, and disconnecting them, comprises two mechanically coupled contact arms both permanently connected to the terminals of one of the devices and one connected to one line of the main circuit, the arms being movable to co-operate with two freed contacts permanently connected to the terminals of the other device and one of them connected to the other end of the line of the main circuit. As shown in Fig 1 applied to the lighting system of a motor vehicle, two similar switches A, B connect the head-lights H<1>, H<2> and the side-lights S<1>, S<2> in series and in parallel, the tail-light being in circuit at all times except when both switches are in the off position. Each switch comprises two insulating-sectors 4 spaced apart and mounted within a casing on the pivot 10 and movable by an exterior lever; the upper sector carries the angularly-displaced contact arm 3. The arm 2 is connected with a contact disc 11 insulated on the spindle and engaged by an upper contact spring 25 fixed externally in the casing and connected to the circuit by the terminal 30. The contact spring 25 is double-ended and serves as a collector for both switches. A lower contact spring engages a lower contact disc in engagement with contact member 3 and is connected to terminal 28, a separate contact spring being employed for switch B and connected to terminal 29. A double-ended non-contact spring 22 engages ntoched discs 16 on the spindles and determines the various positions of the switches. The contact members engage with upper and lower interconnected spring contacts 31, 32 and lower spring contact 33 which is reinforced by a spring steel strip 41 plated with good conductor metal. The contact 33 in all positions of the switch except the off position, is pressed by the lower sector into engagement with a spring contact 44 in the circuit of the tail lamp. The circuit connections are shown in Fig. 1, in which the head-lights are in parallel and the side-lights in parallel. By bringing the contact arms 3 into engagement with the fixed contacts 32, the lamps are connected in series. A diagrammatic arrangement is shown in Fig. 4 for connecting two batteries in series or parallel by means of a switch having two coupled pivoted arms 2, 3.