GB564096A - - Google Patents

Abstract

564,096. Brake-operating mechanism. COMMER CARS, Ltd., and WHITE, G. H. Dec. 8, 1942, No. 17457. [Class 103 (i)] A hand lever is arranged to turn initially about one pivot and when the slack has been taken up and a predetermined force has been applied, about a second pivot whereby the braking pressure is applied at high leverage. According to Figs. 1 and 2, the hand lever 1 is mounted on a pivot 2 carried by the arm 5a of a lever 5 pivoted at 4 to a fixed support 3. The other arm of the lever 5 has ratchet teeth 9 normally engaged. by a spring-loaded pawl 8 carried by the lever 1 and adapted to be disengaged by a lever 1a, a rod 7 and an arm 17a pivoted on the lever 1. The lever 1 is connected at 6a to the brakes by a rod 6. The pivot 2 and thus the lever 5 is normally locked to the support 3 by the engagement of a ball 13 with a recess in the support under the action of a spring 13b in a plug 2a slidable in the pivot against the action of a second spring 13a. Initial movement of the lever 1 takes place about the pivot 2, the pawl 8 slipping over the ratchet 9, but when the slack has been taken up so that the force applied is sufficient to disengage the detent 13, the levers turn together about the pivot 4. In a modification, Fig. 3, in which the parts are duplicated on the two sides of the lever 1, the pawl 8 is pivoted at 8a to the lever 1 and is urged to engage a ratchet 9 on the upper edge of the arm 5b by a torsion coil spring 8b carried by a pin 8f on a plate 8e also pivoted at 8a on the lever 1. A pin 8c on the pawl is free to move in a slot 8d in the plate 8e. To permit the lever 1 to be held in any position it is provided with a pawl 1e mounted in a similar manner to the pawl 8 on a pivot 1f and adapted to engage a fixed ratchet 3b. Rods 7, 7c for operation of the pawls by the handgrip are connected at 7b to the plate 1k, the rod 7 engaging also in a slot 8g in the plate 8e. Rollers 1d on the end 1b of lever 1 engage the arm 5b of the lever 5.