| 摘要 |
PROBLEM TO BE SOLVED: To prevent slipping-off of a seal member certainly. SOLUTION: Mounting of a seal member 20 is made by accommodating in a groove 17 through its narrow opening 17A in the condition that the extension part 21 is stretched to become thin, allowing the extension part to restitute with resilience, and setting a slipoff stopping part 22 in a recess 19. In the mounted condition, the extension part 21 is checked from going through to the side with the butting surface 15 by the narrow opening 17A of the mounting groove 17, while going through to the side with a seal groove 16 is restricted as the slipoff stopping part 22 hitches at the inside wall of the recess 19. |
