GB503096A - Improvements in or relating to motor operated brakes - Google Patents

Abstract

503,096. Brakes; gearing. IGRANIC ELECTRIC CO., Ltd. Oct. 4, 1937, No. 26793. Convention date, Oct. 2, 1936. [Class 103 (i)] [Also in Group XXIV] Brake shoes 2, 3 are applied to a drum 1 by a spring 19, and are released by energizing an electric motor 25. The shoes are mounted on levers 4, 5 pivoted at 6, 7 to a base 8, the 'lever 5 having at its upper end a pivot 9 for an operating lever 10, one end of which is connected by pin 14 and link 13 to lever 4 and the other end 11 engages a slot 43, Fig. 2, in a member 31 adapted to be moved upwardly by the motor 25. The spring 19 tends to draw lever 11 towards a lug 20 on lever 5 and apply the brake. The shaft A, Figs. 1, 2, of the motor drives through a slipping coupling 54.. 56 a nut 27 which engages the screwed part 29 of the plunger 31, balls 34 being introduced into the screwthread grooves which are of a pitch to permit of reversal. The nut is supported on the shaft A by a ball. The plunger 31 slides through a guide member 42 which is recessed to receive oppositely disposed projections 46 on the nut 27, Fig. 4. The lower face of the guide member has oppositely disposed projections 48 adapted to be engaged at the upper limit of the movement by a pin 38 through the member 31. The projections 46 on nut 27 co-operate with a stop 50, Figs. 2, 4 which is held in the slot 43. When the motor is energized, the member 31 is raised until pin 38 engages the projections 48 which stops rotation of the nut 27, and the coupling 64 .. 56 slips and the brake is released. When the motor is de-energized, the member 31 is forced down by spring 19, the nut and motor being rotated until stop 50 engages projections 46; the brakes are then applied. The nut 27 is partly filled with oil, escape of which is prevented by a packing ring 64.