| 摘要 |
PURPOSE:To improve the effectiveness of preventing water invasion or the like and preventing air flowing noise invasion by a method wherein a tubelike communication passage is formed in the cap which permits the ventilation inside and outside the cap while prohibiting the invasion of water and dust into the cap. CONSTITUTION:A grommet 57 is fitted to the side wall of the cap 60 mounted to cover the upper part of a mounting insulator 50 airtightly, a harness 48 is provided airtightly thereon and also a tubelike communication member 61 is fixed passing therethrough airtightly. If the communication passage 62 of this communication member 61 is selectively adjusted to have an appropriate aperture, length and piping means, air can flow freely inwardly and outwardly therethrough, whereas water and dust are prohibited to invade thereinto. With this construction, air an flow into and out of the cap through the communication passage 62 accompanying a pressure change inside the cap caused by the upward and phi downward motion of the piston rod. On the other hand, the design characteristic of the communication passage 62 is effective for preventing the generation of air flowing noise and invasion of water, and for protecting the cap from degradation of function. |
