HYDRAULIC CIRCUIT FOR WORKING CAR

PURPOSE:To enable to widely increase a range of working machines capable of being attached to a working car by forming an exchange position for connecting a large volume pump to the second actuator and for connecting a small volume pump to the first actuator. CONSTITUTION:A three position-switching valve 27 is disposed at the half ways of the first and second oil ways 6, 9. In the three position-switching valve 27, an independent position A for connecting large and small pumps 1, 2 to the first and second actuators 8, 10, a joining position B for connecting the large and small pumps 1, 2 to the second actuator 10 and an exchange position C for connecting the large volume pump 1 to the second actuator 10 and for connecting the small volume pump 2 to the first actuator 8 are formed. Whereby, when a smaller, larger or approximately same volume hydraulic equipment than or as the first actuator is adopted as the second actuator 10, as approximately proper amount or required amount of an oil can be supplied and working machines capable of being attached to the working car can be further widely increased.