| 摘要 |
PURPOSE:To prevent the excessively condensed state of fuel in the mixed gas in the case when a throttle valve is sharply closed and excessive engine brake by installing an air chamber for temporarily storing air and an always-closed opening and closing valve connected to the air chamber, into a bypass passage ranging between the upstream side and the downstream side of the throttle valve. CONSTITUTION:When a throttle valve 7 in the state over a certain opening degree is sharply closed, the negative pressure on the downstream side sharply rises to open an always-closed opening and closing valve 11 installed into a bypass passage 8. From this time, the air on the upstream side of the valve 7 flows into the passage 8 and flows-out to the downstream of the valve 7 together with the air temporarily stored in an air chamber 10. Therefore, excessive engine brake is prevented, and the excessive concentrated state of fuel is prevented. Since almost all of the air in the air chamber 10 flows out and the negative pressure on the downstream side of the valve 7 is reduced, the opening and closing valve 11 is automatically closed, and the flow rate of the air which flows into the bypass passage 8 from the upstream of the valve 7 is regulated, and the air is stored again into the air chamber 10, for the sharp increase of the negative pressure in the next time. |
