| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To improve the suction performance of brake fluid from a reservoir to a pressurizing chamber by a simple structure capable of obtaining a damage preventing effect of a primary cup without enlarging port idle. <P>SOLUTION: In this master cylinder of a type for pressurizing the brake fluid in the pressurizing chamber by sliding of a piston on an inner periphery of a cup held on a cylinder body, a plurality of grooves 16 and 19 are provided on a rear wall of the primary cup formed on the cylinder body 1, that is, in inner peripheral parts of piston guide parts II and V. In the rear parts of the grooves 16 and 19, communicating passages 22 and 24 communicating with the reservoir 8 are provided. In the primary piston 2 and the secondary piston 5, through holes 26 and 27 of the radial direction are provided corresponding to the communicating passages 22 and 24. When each piston is located at a restoring terminal point, a first pressurizing chamber 3 and a second pressurizing chamber 6 are communicated with the reservoir 8 via the through holes 26 and 27, the grooves 16 and 19, and the communicating passages 22 and 24. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
