| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a pump for an anti-lock brake system capable of preventing abrasion of an outer diameter surface of an outer ring and a piston even if the outer diameter surface of the outer ring slidably contacts the piston by operation. <P>SOLUTION: The pump for the anti-lock brake system is provided with a shaft 2 having an eccentric shaft part 1 on an end; the piston 4 stored in a cylinder chamber 23; the outer ring 6 interposed between the piston 4 and the shaft 2; a retainer 7 stored in the outer ring; and a needle roller 8 retained in a pocket of the retainer 7. The outer diameter surface 6a of the outer ring 6 is abutted on an end surface 4a of the piston and a valve 9 is urged to an end at an end on an opposite bearing side of the piston 4. The piston 4 slide-contacted with the outer diameter surface 6a of the outer ring 6 is operated by rotation of the eccentric shaft part 1. A large number of recesses of fine recessed shape are provided on the outer diameter surface 6a of the outer ring 6 at random. A surface roughness parameter Ryni of the surface provided with the recesses is within a range of 0.4μm≤Ryni≤1.0μm. The Sk value is -1.6 or less. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
