GB810817A - Improvements in or relating to speed responsive mechanisms for operating electrical contacts - Google Patents

Abstract

810,817. Centrifugal governors. TELEMECANIQUE ELECTRIQUE. Sept. 3, 1956 [Sept. 2, 1955; June 20, 1956], No. 26900/56. Class 57. [Also in Group XXXVII] A speed-responsive mechanism for operating electrical contacts comprises a rotatable shaft 1 carrying a U-shaped stirrup 5 on which is an axle 7 for a right-angle member having a weight 6 on one arm and the other arm 37 directed towards the shaft axis. A torsion spring 9 on the axle 7 biases the member to the Fig. 1 position where the weighted end engages a stop 5b and the end of the arm 37 clears the end of a key 40 on an offset switch-operating shaft 38. As the speed of the shaft 1 increases the weight moves from stop 5b to a stop 25 and the arm 37 engages a key 39 (Fig. 2) and rotates the spindle 38 through approximately 180 degrees to a position with the key 40 uppermost. When the weight returns to its original position the arm 37 engages the key 40 to restore it to the Fig. 1 position. Fig. 11 shows an arrangement with two weights 6A, 6B for separate setting of the upper and lower operating speeds, arm 37A operating key 39 at the upper limit and arm 37B operating key 40 at the lower limit. The shaft 38 has a cam to operate microswitches 22, 23 and a further cam 59 which has a flat face 60 and rotates between two springs 53, 54 to ensure 180 degrees movement of the shaft 38 at each operation. The axles 7, 7A, 7B are angularly adjustable.