| 摘要 |
A power piston assembly for booster, in particular, an improvement of an axial portion of a power piston and a retainer which is engaged therewith is disclosed. A front power piston is formed with a first and a second tubular section around its inner periphery, and the first tubular section is fitted around a flange of a valve body and is prevented from disengagement therefrom by an annular retainer. Around its outer peripheral edge, the retainer is formed with a peripheral tubular portion, which is disposed as a press fit around the second tubular section of the front power piston from the front side, thereby connecting the front power piston to the flange of the valve body. With this arrangement, the front end of the first tubular section of the front power piston may be located rearward of the front end of the valve body (or its flange). Accordingly, the axial size of the first tubular section and hence of the booster may be reduced as compared with a conventional arrangement. |
