· First application in Volvo models for the U.S. market

· Continuous development for ever lower emissions

It is 30 years since the advent of passenger-car applications for the lambda sensor developed by Bosch. In 1976, the clean technology for low pollutant emissions made its world debut in Volvo's 240/260 range for the U.S. market. As early as 1968, Bosch had used the lambda sensor for oxygen measurement in the manufacture of batteries. When exhaust gas legislation in the U.S. was tightened drastically in the early 1970's, the automotive supplier was able to benefit from this expertise.

Continuous development
In 1982, Bosch brought to market a new development of this tried and tested component. The heated lambda sensor was fully functional within a minute of starting a cold engine. One feature of this new sensor was its longer life – double that of the previous sensor. The sensor, which is heated rapidly to 400 degrees Celsius and is not exposed to extreme temperature variations, has a service life of about 100,000 miles (160,000 kilometers). In 1994, Bosch became the first company to mass-produce the lambda sensor using ceramic planar technology. This model is fully functional just ten seconds after the engine is started. And with the wide-band lambda sensor it is possible to measure rapid changes in the exhaust gas composition in each cylinder and to regulate injection volumes individually for each of the engine's cylinders.

No modern gasoline engine without a lambda sensor
Without the lambda sensor, modern cars with their environmentally-friendly gasoline engines would be unthinkable. Located in the exhaust system both upstream and downstream of the catalytic converter, it measures oxygen content – an indicator of completeness of combustion – and enables optimum operation of three-way catalytic converters. In this way, almost all pollutants are removed from the exhaust gas. The best results are achieved at an air-fuel ratio of 14.7:1. Excess fuel leads to a higher concentration of hydrocarbon and carbon monoxide, while too little fuel gives rise to the formation of nitrogen oxides. The sensor responds to the oxygen content in the exhaust gas and enables the engine management system to make corrective adjustments to the ignition and injection. Since 2002, the lambda sensor has also been used in diesel engines for more precise metering of injection volumes and lower emissions.

The Bosch Group is a leading global supplier of technology and services. According to preliminary figures, some 270,000 associates generated sales of roughly 38 billion euros in the areas of automotive and industrial technology, consumer goods, and building technology in fiscal 2009. The Bosch Group comprises Robert Bosch GmbH and its more than 300 subsidiaries and regional companies in over 60 countries. If its sales and service partners are included, then Bosch is represented in roughly 150 countries. This worldwide development, manufacturing, and sales network is the foundation for further growth. Each year, Bosch spends more than 3.5 billion euros for research and development, and applies for over 3,000 patents worldwide. With all its products and services, Bosch enhances the quality of life by providing solutions which are both innovative and beneficial. The company was set up in Stuttgart in 1886 by Robert Bosch (1861-1942) as “Workshop for Precision Mechanics and Electrical Engineering.” The special ownership structure of Robert Bosch GmbH guarantees the entrepreneurial freedom of the Bosch Group, making it possible for the company to plan over the long term and to undertake significant up-front investments in the safeguarding of its future. Ninety-two percent of the share capital of Robert Bosch GmbH is held by Robert Bosch Stiftung GmbH, a charitable foundation. The majority of voting rights are held by Robert Bosch Industrietreuhand KG, an industrial trust. The entrepreneurial ownership functions are carried out by the trust. The remaining shares are held by the Bosch family and by Robert Bosch GmbH. Additional information can be accessed at www.bosch.com.

PI5205 - February 2006