| 摘要 |
PROBLEM TO BE SOLVED: To provide a hydraulic jack of a hydraulic type elevator, in which a piston can be taken out from above even in a narrow installing area, and a checking and maintenance of seal such as packing and seal ring can be made in place. SOLUTION: This hydraulic jack (1) of the hydraulic elevator extends and contracts a ram (25) housed in a cylinder tube (11) by pressure oil against weight of a cage for carrying persons and/or cargoes. The hydraulic jack (1) comprises the ram having a cylinder tube (27) for the ram arranged coaxially with and inwardly apart from the ram with a given interval, and connected at least at a lower end side thereof with the ram; and a piston (43) detachably attached to a rod (41) fixedly inserted into the cylinder tube for the ram and fixedly arranged therein; and a lid (35) detachably attached on an upper portion of the ram and arranged oppositely to the piston. An inner diameter of the lid is not less than an outer diameter of the piston so that the piston can be taken out from above the ram, and seal and checking of the piston can be easily made. |
