| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a pump tappet capable of attaining a long service life. Ž<P>SOLUTION: The pump tappet 21 includes a shaft 22, and a roller bearing 31 arranged on the outer diameter side of the shaft 22 and rotatably supported on the shaft 22. The roller bearing 31 comprises an outer ring 32 abutting on a cam 12a, and a plurality of rollers 33 arranged between the outer ring 32 and the shaft 22. The shaft 22 has a nitrogen enriched layer and has the grain size number of austenite crystal grain size exceeding No.11 and the residual amount of austenite being 10 to 50 vol.%. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
|
