These benefits have secured a home for piezo injectors in many of the latest diesel and direct- injection gasoline engines. How piezo injectors work – Piezoelectric injectors are highly efficient and allow for several injection events per combustion cycle in modern diesel engines like the current Power Stroke, Cummins, and Duramax models. The key is the innovative injection systeit works with rapid switch, compact piezo -inline injectors. Some advanced common rail fuel systems perform as many as five injections per stroke.
Rival diesel fuel- injector suppliers are fighting a technology duel to win new business as tougher EU emissions rules take effect before the end of the decade.
The common-rail principle remains the core of diesel injection systems. A single high-pressure fuel line is connected to individual injectors at each cylinder. The electronic engine management system controls the precise opening and closing of the fuel-flow valve in each injector. The pressure to reduce emissions of diesel engines is growing. One way to achieve this is to make the combustion of the fuel within the cylinder more efficient.
Injecting fuel in smaller volumes, more frequently and more highly. It enables better fuel economy and emission control.
This paper provides with an overview, design and constructional features , . In advancing diesel engine technology, the key factor lies in further developing a piezoelectric fuel injector in the common-rail system. A direct acting piezoelectric fuel injector prototype for the common-rail system was developed to preserve the lifetime of the actuator, achieve an adequate needle lift, and . These injectors are used in both petrol and diesel engines to improve their persformance and efficiency. Ulrich Dohle, president of the diesel systems division at Bosch, explained how the system works. Piezo Injector Current Test Circuit. Bosch has replaced the magnetic coil usually used to control the injection valve with an actuator made of piezo crystals, which expand within an electrical field.
The piezo element is built into the body of the . High mileage with stable injection volume. CRS 3-diesel common-rail system with piezo injectors and 7bar. Common-rail injection systems.
HFR-high-pressure rail. MDGelectronic engine control unit. Newer generation petrol-injectors are quite different in construction and size than the conventional diesel – injectors.
This new injector is operated via a closed loop needle control mode resulting in a high level of precision and accuracy over the total lifetime. Emissions, operating noise and engine power characteristics are also important.