| 摘要 |
PURPOSE:To improve combustion at the accelerating time during the cold operation of an internal combustion engine, by providing the engine with 3-way solenoid valve capable of switching operation between the cold operation mode and warmed operation mode in accordance with temperature of the internal combustion engine. CONSTITUTION:As a cooling water temperature switch 12 operates during the cold operation time of an internal combustion engine, a primary 3-way solenoid valve 10 closes a negative pressure passage 3a and connects a negative pressure passage 3'b to a secondary by-pass 15. And, therefore, intake negative pressure is transmitted from the negative pressure passage 3b to the primary 3-way solenoid valve 10, a primary by-pass 14 and a 1-way valve 6, and after being adjusted at the 1-way valve 6, the negative pressure is further transmitted to the secondary by- pass 15, a secondary 3-way solenoid valve 11 and the negative pressure passage 3'b to operate a negative pressure advancing angle servo device 5. At this time, a check valve 17 of the 1-way valve 6 is closed by being pulled by negative pressure of the secondary by-pass 15 and the negative pressure passage 3'b, and as variation of the suction negative pressure is transmitted only from an oriffice 8 provided on a partitioning wall 9, ignition advancing angle is delayed. At the time when speed is being reduced, the suction negative pressure becomes extremely high, and the check valve is opened to shift the ignition advancing angle to the early ignition. |
