| 摘要 |
A control valve 26 is operated by air intake vacuum modified by air bled through a line 56 controlled by a differential pressure modulator 40. Sensors 82, 84 sense engine operating conditions and an electronic controller 80 with a memory which provides an optimum control pattern with respect to the engine operating conditions produces a control signal representing an optimum EGR rate which energizes an electromagnetic valve 70. The valve 70 regulates the magnitude of a signal negative pressure to be applied to the pressure modulator 40 so that EGR can be effected exactly at an optimum rate. The electromagnetic valve (90), Figure 2 (not shown), may be opened for controlled duration pulses. <IMAGE> |
