| 摘要 |
PURPOSE:To realize traction control function without impairing safety as well as to reduce parts required in number by additionally providing one traction control valve for a braking device for a vehicle equipped with an anti-skid control device. CONSTITUTION:An electromagnetic pipe line switching valve 57 acting as a traction control valve is a two position three port electromagnetic valve. The switching valve 57 is disposed at the confluent section of a third passing through pipe line 56 with an introducing pipe line 7 for driving wheels at the upstream side of pressure regulating valves 39 and 40. When it is detected by the wheel speed sensors of a right and a left wheel at the time of starting while being accelerated that the right and left driving wheels are going to spin, an electromagnetic pipe line switching valve 45 and the switching valve 57 become excited. This situation thereby allows both the electromagnetic pipe line switching valves 45 and 57 to be switched from each first position to each second position, so that high pressure oil in a hydraulic source 2 is introduced into the pressure regulating valves 39 and 40 of the right and left driving wheels. Brake fluid pressure within wheel cylinders 35 and 36 is controlled to be increased, retained or decreased. |
