| 摘要 |
<p>PURPOSE:To prevent air-fuel mixture from leaking from a downstream chamber of an EGR valve at the time of super-charging, by providing a super-pressing chamber applying super-charged pressure by means of a super-charger between a downstream chamber of a valve of an exhaust gas recirculating device (EGR) and a pressure sensing part. CONSTITUTION:A super-pressing chamber 16 formed above a downstream chamber 13 of a valve of an EGR and below a pressure chamber 11 is connected with the lower stream of a super-charger 6 thrugh a duct 17. Although air-fuel mixture filled up the downstream chamber 13 of the valve of the EGR is apt to leak through a shield part 15 of a shaft, the air-fuel mixture which is apt to leak is pushed back into the downstream chamber 13 of the valve of the EGR as super- charged pressure at an outlet of the super-charger is being applied to the super- pressing chamber 16 and the super-charged pressure is made higher than the pressure in the downstream chamber 13 of the valve of the EGR. With this construction, a leak of the air-fuel mixture from the downstream chamber 13 of the valve of the EGR at the time of super-charging can be prevented completely from occurring.</p> |
