Siemens and Bosch have been jointly awarded the German Future Prize 2005 for the development of piezo injection technology for use in diesel and gasoline engines.
With piezo technology, fuel can be more precisely dosed when injected into an engine’s combustion chamber, considerably reducing fuel consumption and exhaust emissions. In cooperation with developers at automotive supplier Siemens VDO, researchers at Siemens Corporate Technology have been working since the early 1980s to get the process ready for the market.
Piezo injector use a rapid-action actuator made of piezo crystals to control the injection valve. The piezo crystals expand within an electrical field. The electronically controlled piezo actuator switches five times as fast as a solenoid. The movement of the piezo package is transmitted non-mechanically—and therefore entirely without friction—to the rapidly switching nozzle needle. This doubles the injector’s switching speed, allowing a more precise measurement of the amount of fuel injected and thus leading to a reduction in harmful combustion products and increase in fuel economy.
In 2000, Siemens VDO began series production of piezo direct injection for diesel engines. Series production of piezo-based direct injection for gasoline engines is scheduled to start in 2006. Since the mid-1990s, Bosch and Siemens VDO have invested more than €5 billion (US$5.8 billion) in the development and production of piezo technology.
Dr. Klaus Egger and Dr. Hans Meixner of Siemens and a research and development team headed by spokesman Friedrich Boecking from Bosch were awarded the prize in Berlin on November 11.