| 摘要 |
A brake system for a vehicle having a traction control or anti-spin function for controlling wheel spin on differentially driven wheels. The system includes left and right fluid pressure operated brake mechanisms (22, 24) associated with left and right driven wheels (14, 16) of the vehicle. First and second brake valves (80, 82) control fluid pressure to the left and right brake mechanisms (22, 24). In normal operation, an operator actuable treadle (54) operates both valves (80, 82) to apply fluid pressure to the brake mechanisms (22, 24) as a function of treadle depression. Each brake valve (80, 82) includes a pilot pressure operated section (80b, 82b) for actuating a main fluid control section (80a, 82a). Wheel speed sensors (300) monitor rotational speeds of associated left and right driven wheels (14, 16). When slip is detected, a control unit (40) activates one of two pulse width modulated valves (140, 142) to produce pilot pressure in a pilot pressure chamber (130, 132) of the brake valve associated with the spinning wheel.
|
