To smooth a motion when moving a piston in an inside of a cylinder hole while a great load acts thereon, by simple working, and to enhance abrasion resistance or the like.
Micro recesses 21 forming a gently sloped face 21a from the deepest portion toward one side and forming a steeply sloped face 21b in an opposite side are formed over the whole face of a sliding face, on a cylinder hole 12 inner face of a cylinder block 3, and the micro recesses 21 are formed by shot peening working, and are formed by making hard small balls 22 get incident at an angle from an orthogonal direction. A direction of the micro recesses 21 is regulated to be directed to a direction of moving the piston 11 under the action of the high load, i.e. to direct the gently sloped face 21a to a through hole 12a side in the cylinder hole 12, and a wedge film effect is thereby exhibited in an oil film of a hydraulic fluid during an advancing time when advancing the piston 11 into the cylinder hole 12.
TAKEUCHI YOSHINORI
KOKUBU HARUO
| JPS5958171A | 1984-04-03 | |||
| JP2007285312A | 2007-11-01 | |||
| JP2004084622A | 2004-03-18 | |||
| JP2004502092A | 2004-01-22 | |||
| JPH0539775A | 1993-02-19 | |||
| JPH06330849A | 1994-11-29 | |||
| JPS6332175A | 1988-02-10 | |||
| JPH10205437A | 1998-08-04 |
| WO2004055371A1 | 2004-07-01 |
Next Patent: COGENERATION SYSTEM