| 摘要 |
PURPOSE: A hydraulic cylinder is provided to replace a main sealing member without discharging oil by maintaining the sealing of a piston with an auxiliary sealing member if the main sealing member is worn out. CONSTITUTION: A hydraulic cylinder (10) comprises a cylinder body (20) and a piston rod assembly (30). The piston rod assembly comprises a main sealing member (40), an auxiliary sealing member (50), a fluid passage, and a plug (70). The main sealing member and the auxiliary sealing member are installed in the front and rear sides of a piston head (32) to seal working fluid positioned in a first section (24) of a cylinder body. The fluid passage is formed inside the piston head to communicate a second section (26) arranged between the main sealing member and the auxiliary sealing member with the first section. The plug is installed inside the piston head to control the communication between the first and second sections. |
