摘要 |
An exhaust gas recirculator for an internal combustion engine having an exhaust pipe, an intake manifold and a carburetor throttle valve. The exhaust gas recirculator comprises an EGR passage which makes the exhaust pipe communicate with the intake manifold, an EGR controlling valve and an EGR valve respectively arranged in the upper and lower portions of the EGR passage. The EGR valve operates in association with the carburetor throttle valve for metering the flow of EGR gas. The EGR controlling valve is separated by a diaphragm into an EGR gas chamber communicating with the EGR passage between the EGR controlling valve and the EGR valve and a negative pressure chamber communicating with the intake manifold. The negative pressure chamber contains a compression spring, and the diaphragm is connected with a valve member through a rod upon which is disposed a stopper to serve as a different seal in place of the valve member to close off the exhaust gas passage, which valve member and stopper are constructed to be opened and closed by pressure difference between the EGR gas chamber and the negative pressure chamber and by elastic force of the compression spring. The EGR controlling valve functions to control the pressure difference around the EGR valve to be constant.
|