| 摘要 |
1360177 Treating I C engine charges; exhaust gas recirculation NISSAN MOTOR CO Ltd 19 Dec 1972 [25 Dec 1971] 58549/72 Heading F1B An exhaust gas recirculation system, for an I. C. engine including an intake manifold 12, an exhaust manifold 14 and a secondary air supply device having a pneumatic pump 18 driven by the engine and feeding an air gallery 22, at least one secondary air injection nozzle 24 communicating with the air gallery and exhaust manifold, the exhaust gas recirculation system comprising, in combination, a conduit 42 extending between the exhaust and intake manifolds for recirculating exhaust gas to the intake manifold, valve means 30 in the conduit to control the amount of exhaust recirculation, valve actuating means having a movable member connected to a valve head 32 and having a control chamber 40 communicating with the air gallery 22 and control means 48 for controlling the pressure of secondary air in the control chamber 40 in dependence on the variation in intake manifold vacuum. The secondary air passage includes a solenoid valve 44 which closes the passage, when de-energized, while the engine is idling or running light. The control means 48 consists of a branch passage 46 connecting with the secondary air passage between the control chamber 40 and the shut-off valve 44 and vented to atmosphere, a valve element 58 to control the effective cross-sectional area of the passage 46 and a diaphragm 54 connected to the valve. One side 52 of the diaphragm is open to atmosphere and the other side is connected by a pipe 56 to the intake manifold, a spring 62 biassing the valve element 58 to the closed position. In a modification, the passage 46 is not vented to atmosphere but is connected directly to the intake manifold and includes a fixed flow restrictor. In a further modification the valve 30 consists of a bellows the interior of which communicates with the air gallery and one end of which is mechanically connected to the valvemember 32. |
