PURPOSE: To elevate all the wheels of a vehicle in the air and keep horizontally the body of the vehicle by using the hydraulic jack fitted to each of the outriggers set up at four positions of the front and rear sides of the vehicle.
CONSTITUTION: After setting each of all four hydraulic jacks 18's on the ground, discrimination between the hydraulic jack positioning the highest level among four hydraulic jacks and the remaining three ones is performed, and by using the hydraulic jack 18 positioning the highest level as the base level, the hydraulic oil is supplied into an extension oil chamber 18a of each of the remaining three ones and the supply is stopped when both first and second diagonal clinometers 32 and 33 detect horizontality with all the wheels on the ground. Thereafter the hydraulic oil of same quantity is supplied to the extension oil chamber 18a of each of all the hydraulic jacks 18's through each of the flow controllers 29's with pressure compensation so that the body can be lifted up to an elevation where all the wheels are free from the ground in same lifting pace of these jacks.
MAEWADA AKIRA