GB353603A - Improvements in high tension air break electric switches - Google Patents

Abstract

353,603. Air-break switches. ASSOCIATED ELECTRICAL INDUSTRIES, Ltd., Bush House, Aldwych, London.-(Assignees of Koppitz, C. G. ; of Railway & Industrial Engineering Co., Greens burg, Pennsylvania, U.S.A.)- May 28, 1930, No. 16480. Convention date, May 29, 1929. [Class 38 (v).] High-tension air-break switches designed to have high contact pressure between a flattened contact head and a U-shaped jaw both carried by separately pivoted arms supported about spaced parallel axes have the flattened contact head so shaped that when it is introduced into the jaw prior to the final movement of said arms the contact head is inclined to the basal and medial planes of the U-shaped jaw, so that the final movement of the arms rotates the flattened element within the jaw so wedging it firmly therein. As shown in Fig. 1, the U-shaped jaw comprises a rigid arm 10 of soft metal such as copper and a springy arm 11 of hard metal such as chromium-plated steel between which the flattened contact head 11 is adapted to engage the jaw and flattened contact being carried by arms 8, 9 pivoted at 13 to plates 6 attached to rigidly mounted insulators 3. The switch arms are operated through rotatable insulators 2 pivotally mounted on the support 1, the operating force being applied to a crank 17 on the left-hand insulator and transmitted to the right-hand insulator through cranks 18 joined by a link 19. The upper ends of the insulators 2 carry crank arms 14 joined to the switch arms 8, 9 through links 15 having universal bearings 16 at either end. During the switch-closing movement, Fig. 4, the flattened contact head enters the U-shaped jaw as shown in dotted lines so that the final closing movement rotates the head within the jaw so wedging it firmly therein. The contact head is formed of phosphor bronze or similar metal the relative rotation of the head within the jaw producing a self-cleaning action between the contacts. The switch may be modified, Figs. 6 and 7 (not shown), for movement of the contact arms in a horizontal plane.