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U.S. Department of Energy
Office of Scientific and Technical Information

Exhaust gas recirculation for an internal combustion engine

Patent ·
OSTI ID:5645771
A back pressure control type EGR system is disclosed wherein a vacuum line for connecting an EGR port with a vacuum operated EGR valve for controlling the amount of the recirculated exhaust gas is selectively opened to an air chamber of a vacuum modulator valve responsive to the pressure of the recirculated exhaust gas. The air chamber is connected, via a vacuum line, to a second vacuum port located slightly above the EGR port. A vacuum switching valve responsive to vacuum pressure at a third port formed in an intake manifold is arranged in the vacuum line.
Assignee:
Toyota Jidosha Kogyo K K (Japan)
Patent Number(s):
US 4206731
OSTI ID:
5645771
Country of Publication:
United States
Language:
English