Exhaust gas recirculator for purification of emission from an internal combustion engine

An exhaust gas recirculator for purification of emission from an internal combustion engine, comprising:

• a cylinder;
• an intake manifold connected to said cylinder;
• an exhaust pipe;
• an exhaust gas recirculation pipe connected between said intake manifold and said exhaust pipe;
• a recirculation control valve inserted midway in said exhaust gas recirculation pipe, which has a diaphragm, a diaphragm chamber provided at one side of said diaphragm and connecting to said intake manifold, a valve body configured substantially as a truncated cone and connected to said diaphragm, and a plurality of springs provided in series in said diaphragm chamber and working such reaction force on said diaphragm as varies phasedly in accordance with the displacement of said valve body;
• and
• a plurality of orifices opened in the valve chamber of said recirculation control valve, and arranged in combination around said valve body, said orifices being constituted such that they can change the flow area in the valve-opening direction of the valve body, which is controlled by the negative pressure of said intake manifold, whereby the flow rate of exhaust gas recirculated to the intake manifold can be continuously controlled by the displacement of the valve body caused by the negative pressure of the intake manifold.