EGR Butterfly Valve with a Reed Valve Bypass
Publication Date: 2016-Aug-11
The IP.com Prior Art Database
Page 01 of 3
Title: EGR Butterfly Valve with a Reed Valve Bypass
Brief Description of the Drawings:
Figures 1‐4 schematically illustrate various operational positions of a butterfly valve and reed valve bypass arrangement of an EGR (exhaust gas recirculation) valve of an (EGR) system of an internal combustion engine.
As shown in the attached illustrations and described below, an EGR (exhaust gas recirculation) butterfly valve and reed valve arrangement that allows an EGR loop to be utilized in reverse through a bypass passage around the EGR butterfly valve, is disclosed.
EGR systems and the control of EGR systems are often the primary components and means of an internal combustion engines, e.g., diesel engine, with regards to efforts to reduce NOx emissions. These systems reroute exhaust gas from an exhaust manifold through a cooler and then back into an intake manifold, which reduces oxygen levels, lowers exhaust temperatures, and reduces levels of NOx. An EGR valve is used for controlling the EGR flow rate. Pressure difference between the exhaust manifold and the intake manifold is also controlled in order to provide an adequate EGR flow.
Figure 1 schematically illustrates a butterfly valve and reed valve arrangement of an EGR valve shown in a fully open position. Gas flow from the exhaust manifold to the intake manifold is not restricted by the butterfly valve. The reed valve is locked in a closed position by a rib arranged on the back of the butterfly valve. This arrangement may be desired in situations such as high negative engine dP (differential pressure) operation to allow EGR flow, and there is adequate engine dP generated from general air system conditions.
Figure 2 illustrates the butterfly valve and reed valve arrangement of Figure 1 in a standard closed position. The butterfly valve is in a closed position. Rotational positional control of the butterfly valve may be accomplished by an actuator such as a DC motor (not shown). The reed valve is locked in a clos...