| 摘要 |
<p>PURPOSE: To provide an exhaust pipe joint low in the noise level leaking outside, without needing to fit an inner blade inside a bellows. CONSTITUTION: A bellows 15 of three-layer structure with a ceramic cloth layer 22 sandwiched between an inner pipe 21 and an outer pipe 23 is used. The inner pipe 21 is strongly excited being directly exposed to engine noise, the pressure fluctuation of exhaust gas and acoustic wave, but the vibration of the inner pipe 21 is cut off by the ceramic cloth layer 22 so as not to be transmitted to the outer pipe 23, and the ceramic cloth layer 22 has damping function by the mutual friction of fibers so as to suppress noise offensive to the ear and high frequency vibration of about 1kHz. Since the heat insulating effect of the ceramic cloth layer accelerates the temperature rise of a catalytic converter disposed downstream, exhaust gas purifying performance is also improved.</p> |
