Patent ID: 6119454
Filing Date: 2000-09-19
Classification: F01N,F02B,Y02A,Y02T,Y10T

Abstract:
An aspirator for allowing air automatically to selectively enter an engine exhaust manifold during operation of an internal combustion engine to inhibit exhaust gases being drawn back into the cylinders via exhaust valves, the aspirator comprising an adapter formed by a hollow body that extends to a port fitted in communication with the manifold, a first one way valve fitted to the adapter that prevents gases leaving the manifold through the port when the pressure inside the manifold is greater than the pressure at the first valve, and means for supplying air to a second one way valve at different pressures, above atmospheric pressure, that increase with increases of speed of the engine, in which the second one way valve is connected by a passageway to the first valve forming an intermediate expansion chamber having a relief port to atmosphere, the second one way valve being arranged to allow air to enter the passageway whenever the pressure inside the passageway is less than the pressure at the second valve.