| 摘要 |
<P>PROBLEM TO BE SOLVED: To maintain initial performance of a lash adjuster having non-parallel pressure-side flanks of female and male screws. <P>SOLUTION: A male screw 25 on the outer circumference of an adjustment screw 24 for automatically adjusting a valve clearance is threaded to a female screw 23 provided on the inner circumference of a screw hole 21. The adjustment screw 24 is biased by a return spring 26 in a direction of projecting from the screw hole 21. A flank angle of the pressure-side flank 30 of the male screw 25 that receives an axial load when the adjustment screw 24 is pushed in is different from that of the pressure-side flank 29 of the female screw 23, thereby preventing an oil film from being formed between the pressure-side flanks 29, 30. In the threads of the male and female screws 23, 25, surface hardness of the thread on the pressure-side flank having a larger flank angle is made higher than that of the thread having a smaller flank angle, to prevent the pressure-side flank having a larger flank angle from being worn. <P>COPYRIGHT: (C)2013,JPO&INPIT |
