| 摘要 |
<p>In an internal combustion engine having a combustion chamber, an exhaust port for discharging exhaust gases from said combustion chamber, an exhaust pipe extending from said exhaust port for conveying exhaust gases therefrom, and an expansion chamber (20), being in communication with said exhaust pipe and into which said exhaust pipe discharges, adjustable reflecting means (36a-α) are provided, positioned in a confronting relation to the end of said exhaust pipe for providing a variable reflective area at the end of said exhaust pipe upon which acoustic waves in exhaust gases in said exhaust pipe will reflect for reducing the pressure at said exhaust port and selectively operable means (42,44a,46,44b) for adjusting said reflecting means effective area in response to an engine condition.</p> |
