GB452951A

GB452951A - Improvements relating to drum-type electrical controllers

Info

Publication number: GB452951A
Application number: GB2039235A
Authority: GB
Original assignee: CHARLES HENRY LAST; Metropolitan Vickers Electrical Co Ltd
Current assignee: CHARLES HENRY LAST; Metropolitan Vickers Electrical Co Ltd
Priority date: 1935-07-17
Filing date: 1935-07-17
Publication date: 1936-09-02

Abstract

452,951. Controllers. SCARF, C. T., 58, Hale Road, Hale, Cheshire, LAST, C. H., 101, Wilmslow Road, Rusholme, Manchester, and METROPOLITAN - VICKERS ELECTRICAL CO., Ltd., 1, Kingsway, London. July 17, 1935, No. 20392. [Class 38 (iii)] In a controller of the kind in which a rotary member or drum is arranged to be rotated in both directions from its " off position to which it is biassed, a member 7 is adapted to be given, as the result of movement of the drum under its biassing means, a sudden movement against a biassing device 13 so as to be brought into the path of movement of the drum or a member 4 secured thereto and to romain by virtue of its inertia in the said path of movement sufficiently long to intercept the drum or the member 4 and arrest it in the " off position. The controller has the usual star-wheel 1 and cooperating lever 2, and secured to the drum shaft is a disc 4 with a radially-sided notch 5 and a projection 6, the circumferential width of the projection 6 is considerably less than that of the notch 5. A bell-crank lever 7, pivoted at 8, has a hooked arm 10 which engages the notch 5 in the off position of the drum, and a roller 14 biassed by a spring 13 to engage the edge of the disc 4, the projection 6 engaging the roller 14 in the off position of the drum, the length of the hook 11 is smaller than the depth of the notch 5. When the drum is released from an operative position it moves to its " off " position and the projection 6 strikes the roller 14 to rotate the lever 7 and cause the hook 11 to move into the notch 5. If the drum is moving so quickly as to be liable to overshoot the " off " position the lever 7, due to its inertia, does not move back quickly enough to lift its hook 11 clear of the notch 5, and the drum is prevented from moving too far. With a slow movement of the drum through its '' off " position the movement of the lever 7 follows the shape of the disc 4 and the hook 11 will move back to clear the notch 5.