| 摘要 |
The invention concerns a piston wherein the mobile screw ( 2 ) is engaged in the bolt ( 8 ) integral with the mobile assembly ( 1 ). It is provided with a cylindrical axial housing ( 10 ) wherein is engaged the rod ( 7 ) integral at its front end with the expander assembly ( 4 ). At the end of its front travel, the rod is retained by its flange ( 19 ) pressed on the stop ( 11 ) such that the expanding ring ( 5 ) is compressed by the thrust of the piston body ( 3 ) and causes the flexible envelope ( 6 ) to expand. |
