| 摘要 |
A vehicle power braking system has separate left and right brakes (11, 12) operable from a source of pressurized fluid (13) via relay valve means (16) controlled by separate left and right brake operating pedals (14, 15) to provide steering assistance during a turn. The relay valve means delivers a brake operating pressure proportional to the depression of the associated brake operating pedal to separate left and right shift valves (17, 18), each shift valve being connected with its respective operating pedal (14, 15) by a respective pilot line (19, 20) so that when each pedal is operated the associated shift valve is opened by the respective pilot line pressure to supply the proportional pressure from the relay valve means to the respective brake (11, 12). The relay valve means comprises a single relay valve (16) which supplies both shift valves (17, 18) and the pilot lines (19, 20) are interconnected via a shuttle valve (21, 22) so that the highest pilot pressure generated by operating the brake pedals (14, 15) is applied to the single relay valve (16) so that each shift valve receives the same brake applying pressure proportional to said highest pilot pressure. |
