| 摘要 |
<p>A hydraulic jack is disclosed having a variable volume working chamber 26 defined by a piston 14 reciprocable within a cylinder bore and a port 22 for allowing hydraulic fluid to enter and leave the working chamber. In order to avoid accumulation of air within the working chamber 26, an insert 16' is positioned in the cylinder bore to define therewith an annular passage 40 in communication with the port 22, the annular passage also communicating with the working chamber 26 through a gap 42 between the radially outer surface of the insert 16' and the cylinder bore. <IMAGE></p> |
