GB445713A - Improvements in or relating to vehicles propelled by internal combustion engines - Google Patents

Abstract

445,713. Controlling motor vehicles ; fluid-pressure brakes. TAPP, E. T. J., 10, Manville Road, Tooting Common, London. Oct. 19, 1934, No. 29975. [Class 79 (v)] [See also Group XXXIV] In a vehicle of the kind wherein governor controls the brake and throttle whenever a predetermined vehicle speed is exceeded, the brakes are controlled by the vacuum created in the engine induction pipe by the closing of the governor throttle. The governor may act on the usual driver-controlled throttle or on a separate throttle. In the construction shown in Fig. 1, the throttle b is controlled by the accelerator pedal through a spring l, and by the governor (not shown) through a rod c and a stronger spring g. When a predetermined vehicle speed is reached the governor rod c moves to the left and first closes the throttle after which one of two collars n on the rod rocks a lever m and opens a valve f connecting the brake pipe e with the induction pipe a in which there is a vacuum caused by the closing of the throttle. When the speed falls again the rod c moves to the right, opening a valve f<1> connecting the brake pipe e to the atmosphere. In the construction shown in Fig. 3, the throttle b is operated by an arm s connected to the accelerator pedal (not shown), and the governor rod c is connected to an arm t of a rotary valve o which can connect the brake pipe e either to the induction pipe through a port q or to the atmosphere. The arm s is normally held by a spring against a stop t<1> on the arm t so that the two arms are moved together by the governor rod until the throttle is closed, after which the arm t moves alone to apply the brakes. In the construction shown in Fig. 5, the accelerator pedal controls a throttle 7 and the governor a throttle 6. A flexible diaphragm 5 communicates through pipes 9, 11 with the induction pipe above and below the throttle 6 so that when 6 is open the pressure above and below the diaphragm is equalized. When the governor closes the throttle 6, the pressure below 6 is greater than above, the usual throttle 7 never being completely closed, so that the diaphragm 5 moves upwards and a valve 4 connects the brake pipe 13 to the pipe 11 and the induction pipe to apply the brakes. The diaphragm movement may be accelerated by an additional valve 10 which is opened as the throttle 6 closes and admits air to the lower side of the diaphragm. The valve 4 may control the supply of pressure fluid to the brakes if they are of the pressure-operated type. In tractor-trailer vehicles the brakes may be applied on both vehicles or on the trailer only. According to the Provisional Specification the governor (1) may act directly and successively on the throttle and a brake valve, or (2) applies centrifugal brake pads against a surface which first rocks slightly to operate the brake valve, further increase in speed causing these pads to act as a mechanical brake.