| 摘要 |
<p>PURPOSE:To recirculate gas suitably on the basis of the operational condition. CONSTITUTION:A proper EGR ratio is determined on the basis of the signals from a suction-air sensor 35 and an engine rpm. sensor 37 Depending on the ratio, a signal is put out from a control circuit 10 to a solenoid valve 11. The value of a control negative pressure Po is regulated in proportion to the determined opening of the solenoid valve 11, which is let to a pressure chamber 16 of a differential-pressure converter 12 through a duct 19. As negative pressure rises, the diaphgram 14 is displaced upwards against a return spring 34 because the pressure influence area of the diaphgram 14 is larger than that of the diaphgram 13. The valve seat 20 of the diaphgram 13 therefore makes an atmosphere inlet pipe 21 reduce in opening. The result of less air dilution ratio increases the control negative pressure P3 affecting the exhaust recirculation valve 6 to gain the opening of the control valve.</p> |
