Forklift and a hydraulic system and the hydraulic system

摘要

PROBLEM TO BE SOLVED: To provide a hydraulic system that can increase the rigidity of masts and a forklift with the same.;SOLUTION: A hydraulic cylinder 2 comprises hydraulic cylinders 6L and 6R for lifting/lowering inner masts along outer masts, opening/closing means 8 for opening/closing a bottom side circuit Ca connected to bottom chambers 62L and 62R and a rod side circuit Cb connected to rod chambers 63L and 63R, and hydraulic fluid supplying means 7 for supplying hydraulic fluid to the hydraulic cylinders 6L and 6R. By using the opening/closing means 8 to close one circuit of the circuits Ca and Cb, which discharges hydraulic fluid from the hydraulic cylinders 6L and 6R, when stopping piston rods 61L and 61R and then close the other circuit and by using the hydraulic fluid supplying means 7 to supply hydraulic fluid to the hydraulic cylinders 6L and 6R through the other circuit for a period of time between one circuit has been closed and the other circuit is closed, the pressure of hydraulic fluid in both circuits Ca and Cb is increased.;COPYRIGHT: (C)2015,JPO&INPIT