| 摘要 |
PURPOSE:To accurately control an intake control valve always in accordance with an intake air quantity, by controlling the intake control valve to be opened and closed through a resultant negative pressure from the negative pressure generated in a primary bore in the upstream side from a primary throttle valve and the negative pressure generated in a secondary bore in the upstream side from an air valve. CONSTITUTION:A resultant negative pressure, arising from the negative pressure generated in a primary bore 42 in the upstream side from a primary throttle valve 44 and the negative pressure generated in a secondary bore 43 in the upstream side from an air valve 47, is applied to a diaphragm chamber 23 in a negative pressure control valve 21. When the resultant negative pressure is a prescribed value or less, the negative pressure control valve 21 is closed, and intake pipe negative pressure is introduced to a diaphragm chamber 17 of a diaphragm device 14, then an intake control valve 11 is placed in a fully closed position. When the resultant negative pressure is a prescribed value or more, the negative pressure control valve 21 is opened, and the atmospheric pressure is introduced to the diaphragm chamber 17, then the intake control valve 11 is placed in an opening position. |
