World's first to integrate air intake throttle valve and EGR valve and half the size of conventional models
Global automotive supplier DENSO has developed an exhaust gas recirculation (EGR) valve unit, a major component of EGR systems that helps make diesel engine emissions cleaner. The new unit, the first in the world to integrate an air intake throttle valve and an EGR valve, is half the size of conventional models and requires fewer components, thus reducing costs. The unit will be installed in a diesel passenger vehicle to be sold in Europe from later this year.
Conventionally, air intake throttle valves and EGR valves were separately installed to vehicles. The air intake throttle valve controls the amount of air entering the engine and the EGR valve controls the amount of exhaust gas to be recirculated into the engine. By integrating the two valves into one unit, DENSO combined the ducts and reduced the connectors, resulting to reducing the size to half compared to previous models. As the EGR system needs to be installed in a limited space close to the engine, a smaller system enables automakers to design engines more flexibility.
Conventionally, a motor for valve opening and closing, paired with a sensor to detect the valve opening and closing angle, were needed for both the air intake throttle valve and EGR valve. However, DENSO's new unit, which integrates the two valves, needs only one motor and one sensor, thus reducing the cost.
Flexible to meet various engine parameters
The air intake throttle valve and EGR valve are connected through a highly flexible coupling (cam-link mechanism), allowing the new unit to be applied to various engine parameters, including displacement and output, merely by changing the shape of the connection between the two valves (cam profile).