| 摘要 |
<p>PURPOSE:To provide the compact intake device of an engine by which a high resonance effect is obtained in a wide rotating range, and the radiating sound of a resonance chamber can be reduced. CONSTITUTION:A first opening/closing valve 31 is provided in the space part inside a surge tank 26, and the space part is partitioned into first and second separated chambers 27, 28 when the valve 31 is closed. A communicating passage 33 for communicating the first and second separated chambers 27, 28 with each other is formed in one body with the surge tank 26, and a second opening/ closing valve 34 is provided in the communicating passage 33. In a low speed range, the first and second opening/closing valves 31, 34 are closed to carry out resonance supercharging while forming first and second branch intake passages 24, 25 as resonance passages. In an intermediate speed range, the second opening/closing valve 34 is opened to carry out resonance supercharging while forming the communicating passage 33 as a resonance passage. However, since the diameter of the communicating passage 33 is set to be large while its length is set to be long, propagation resistance of pressure wave is reduced, and resonance effect is improved. And also stiffness of the surge tank 26 is improved so as to reduce radiating sound.</p> |
