| 主权项 |
1. Bottle jack (1) comprising a main body (2) and a shaft (5) expanding or contracting with respect to the main body (2) for lifting and lowering a load, where the shaft (5) expands due to pressure exerted by a hydraulic fluid contained in a hydraulically operated circuit (6), characterized in that it comprises:
a passage space (12) communicating the hydraulically operated circuit (6) with an unloading circuit (13) through which the controlled outlet of hydraulic fluid from the hydraulically operated circuit (6) and subsequent lowering of the shaft (5) can occur; a closure element (14) located in the hydraulically operated circuit (6) and elastically pushed towards the passage space (12) to close said passage space (12) and preventing the controlled outlet of hydraulic fluid through the passage space (12); a ram assembly (16) provided with an outer end (18), outside the unloading circuit (13), and an inner end (17), inside the unloading circuit (13), said ram assembly (16) being movable with respect to the passage space (12) in a longitudinal forward movement direction (A) towards the passage space (12) and in a longitudinal backward movement direction (B) opposite the longitudinal forward movement direction (A), where the inner end (17) of the ram assembly (16) pushes the closure element (14) and separates said closure element (14) from the passage space (12) when the outer end (18) is pushed, moving the ram assembly (16) a sufficient distance in the longitudinal forward movement direction (A); where the ram assembly (16) is elastically pushed in the longitudinal backward movement direction (B) with a force greater than the force with which the closure element (14) is elastically pushed against the passage space (12), and in that it further comprises: a lever assembly (36) which can be lowered by a user to operate the hydraulically operated system, where said lever assembly (36) is telescopic and the total length of the lever assembly (36) is variable. |
