摘要 |
<p>In an intake system for an engine incorporated with a resonance chamber ( 32 ), a variable communication unit ( 50 ) for controlling the communication between an intake passage with the resonance chamber comprises an outer tube ( 51 ) having an open axial end ( 51 a) and an opening ( 51 b) defined in a circumferential wall thereof for communication with the resonance chamber and an inner tube ( 52 ) rotatably and coaxially received in the outer tube, the inner tube being provided with a communication inlet port ( 52 a) at an axial end on a same side as the axial end of the outer tube and an opening ( 52 b) in a circumferential wall thereof for defining a communication outlet port ( 50 a) jointly with the opening in the outer circumferential wall of the outer tube. The openings of the inner tube and outer tube are configured such that at least one of a distance (L) between the inlet and outlet ports of the communication passage and an opening area (S) of the communication outlet port changes in relation with a relative rotational angle between the inner tube and outer tube. Thereby, the intake system can be formed as a highly compact unit and requires little power to operate.</p> |