GB624968A - Tuning mechanism for radio apparatus - Google Patents

Abstract

624,968. Push-button tuning mechanism. GENERAL MOTORS CORPORATION. July 18, 1947, No. 19251. Convention date, Feb. 15, 1940. [Class 40 (v)] In a push-button tuning mechanism the tuning elements 20, Figs. 2 and 3, which may be movable magnetic cores, are connected to a member 76 which is movable about a pivot 70 and is biassed in an anticlockwise direction by a spring 78. The buttons 14 are attached to threaded rods 30, which are biassed outwards by springs 36, and carry threaded angled brackets 42 provided with an extension running in a slot 52 to prevent them from turning. The rods 30 are locked in their innermost position by the spring-biassed plate 64 and as one rod is pressed in, the plate is forced down to release any other rod which may be locked in. The shaft 74, which is attached to shaft 76 by links 72, co-operates with any of the adjustable brackets 42 to operate the tuning elements. The position of the brackets on the threaded portions of the rods determines the position of the tuning mechanism 18, 20, and may be varied by rotating the rods, a spring 56 ensuring that the brackets remain in a set position. When the manual tuning knob 10, which is connected to a rod 30<1> substantially identical with the other rods, is forced inwardly, the mechanism locks over the plate 64, and the knob may be rotated to cause the angled bracket 42 to travel, turning the lever arm 72 about the pivot 70 until the desired station is received. The Specification also describes mechanism.for transmitting the movement of the lever arm 72 to an indicating needle.