| 摘要 |
<P>PROBLEM TO BE SOLVED: To extend the life of a roller by reducing a load acting on an all-round projection of the roller from the outside. <P>SOLUTION: A piston rod 5 is sandwiched between a positioning member 21 of a groove machining device 11 and a pressing member 22 to be axially positioned, and while respective rolling rollers 14, 18 are rotationally driven, all-round grooves 14B, 18B thereof are pressed against the outer peripheral surface of the piston rod 5 to machine the all-round groove thereof. In process of machining the all-round groove, the positioning member 21 and the pressing member 22 are separated from the piston rod 5, and both the end sides of the piston rod 5 are brought into a free state. Thereby, even when the piston rod 5 is axially elongated in machining the all-round groove, the piston rod does not butt against the positioning member 21 and the pressing member 22, whereby the lives of the respective rolling rollers 14, 18 can be extended by reducing the load acting on the all-round projections 14B, 18B from the piston rod 5. <P>COPYRIGHT: (C)2013,JPO&INPIT |
