| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an inexpensive valve guide excellent in corrosion resistance and workability. <P>SOLUTION: The valve guide 1 for guiding an EGR valve 13 of an EGR valve device 10 is formed of a hard porous carbon material. Therefore, even if condensate having strong corrosiveness falls on the valve guide 1, especially on a part exposed inside an exhaust gas passage 15, corrosion of the valve guide 1 can be positively prevented, and durability of the EGR valve device 10 can be significantly improved. As the hard porous carbon material, RB ceramics (rice bran ceramics) using rice bran as a raw material is used. Since rice bran is inexpensive and is machine processable, the inner diameter size of a sliding hole 2 which is a sliding face and the external dimensions of the outer periphery serving as a press-fitting face can be accurately processed. <P>COPYRIGHT: (C)2007,JPO&INPIT |
