| 摘要 |
Purification of IC engine exhaust gases, provided with controlled buffer storage for gases during initial cold start-up. IC piston engine (10), with inlet manifold (12), butterfly throttle (14), and exhaust manifold (16) discharging into exhaust pipe (18) is provided with 3-way catalytic converter (20). A lambda probe (oxygen analyser) (22) is fitted into exhaust pipe (18), and provides a control signal to the fuel/air proportioning unit. Downstream of (22) the exhaust pipe branches (26) to a buffer vessel(28); the junction is fitted with an electro-magnetic actuated flap valve (30), above to close off either the buffer or exhaust discharge to the catalyst chamber. Buffer vessel (28) also connects into the inlet manifold (12). Buffer inlet line (26) includes a pump (34) and a non-return valve (36); a further non-return valve (38) is fitted between buffer vessel (28) and inlet manifold (12). The catalyst (20) and probe (22) each have electric resistance heaters; buffer vessel (28) has a pressure sensor (50). On completion of the ignition circuit, controller (40) decides if cold-start conditions apply (e.g. engine below 20 deg C), and if so, energises pump (34), and the resistance heaters, and closes the exhaust line via valve (30). In this way exhaust gates are contained for a few seconds, until a pre set pressure is attained, and then recycled to the engine inlet manifold. The now hot exhaust gases can be diverted to the catalyst chamber (20) at a temp. allowing effective oxidn.. |
