GB221196A - Improvements in or relating to vehicle brake apparatus - Google Patents

Abstract

221,196. Renault, L. Aug. 28, 1923, [Convention date]. Actuated by running axle.-A servo-brake device operated by the rotation of a wheel axle is designed so as to enable the brakes to be applied when the vehicle is travelling either backwards or forwards, or is at rest; in modifications, when the vehicle is travelling forwards, or is at rest Fig. 1 shows a servo-brake operating mechanism comprising a band 3 connected at its ends respectively to an operating pedal and to the brakes and surrounding a pulley 2 loosely mounted on an axle 1. When the band 3 is tightened round the pulley, the screw 6 moves it to the right or left, according as the vehicle is moving backwards or forwards, and engages the pulley with either the cone 10, which is rigid with the axle 1, or with the cone 16, which is driven from the shaft 1 by means of an intermediate gear wheel 13. In either event the pulley 2 is rotated in the same direction and the brakes are applied. In a modification the cone 16 and its accessories are omitted so that the servo-brake device operates only when the vehicle is travelling forwards, and this may be further modified by replacing the friction clutch 10, 2 by a dog-clutch. The shaft 1 is driven by the gear 19 through dogs 17, 18, the play between which facilitates the disengagement of the clutches. Fig. 6 shows a. device in which worm gearing 29, 32 rotates a shaft 33, on which the servo-motor pulley or drum is mounted. When the drive is such that the worm 29 moves to the right, the clutch 26, 27 engages; when the vehicle travels backwards, the clutch 26, 27 disengages, and the plate 34 abuts against the plate 36, which, with the spring-pressed part 35, forms a friction clutch; this slips as soon as the brake control is operated, and the brakes are applied without using the servo-motor.