GB383761A - Improvements in or relating to electrically operated indicating mechanisms - Google Patents

Abstract

383,761. Two-position indicators. GENERAL ELECTRIC CO., Ltd., Magnet House, Kingsway, London, and ROSE, W. R., of General Electric Co., Stoke, Coventry. Dec. 9, 1931, No. 34137. [Class 40 (i).] In a two-position indicator wherein the indicating member is operated by the pivoted armature of a pair of electromagnets, the armature co-operates with the indicating member through the intermediary of a spring which acts also to retain the indicating member and the armature at either of their extreme positions. As shown in Fig. 3, the armature 13 carries a spring 20 of substantially straight wire which engages under slight downward tension a forked member 17 on the shaft 24 of the indicating disc 18. The disc and the armature are thus retained in one of their extreme positions against a stop e.g. 25 under the action of the spring. When the armature is rocked into its other position, the spring 20 rotates the forked member and is bent during movement until it reaches a " top dead-centre " position, whereafter it assists the armature to move the disc, the assembly finally coming to rest with the forked member resting against the stop 23 and being urged to retain this position under the action of the spring. The indicating member may be painted black with a white diametrical stripe, and the assembly may be mounted in a cylindrical case having a transparent front. In a modified form the end of the spring 20 co-operates with a vertical slot in the back of a slidable indicating member. Fig. 4 shows the operating circuits of the indicator. Operation of key K to the right energizes coil R which throws over the armature. The armature operates contact r<1> which opens the energizing circuit and prepares the circuit of the other coil.