An important criterion for the development of an automobile is the compliance with the legal emission standards. In order to adhere to these emission standards it is, amongst other things, necessary to ascertain the exact relationship between the air mass to the fuel quantity. The ascertainment of the air mass is undertaken by the so-called “Air Flow Meters”.

It is used to measure the air mass flow in combustion engines (e.g. petrol and diesel motors) and provides the motor management or the fuel-injection system with relevant values via its electronic output signals. These values are needed by the motor management in order to exactly define the injected fuel quantity, dependent on the currently needed performance, the air pressure and the air temperature.

Assembly

The actual sensor is integrated in the flow channel of the pluggable sensor. These pluggable sensors are suitable for the installation in the air filter, as well as in so-called gauge tubes, which one can find in automobiles. An electronic measuring system transforms the sensor data into corresponding measuring data for the motor management / the fuel-injection system.

Function

The functional principle is based on an indirect measurement of the air current. A heating element is supplied with power during operation and thereby heated up. The on-rushing air now causes a cooling down of the heating element. The heat that is detracted from the heating element gives information about the on-rushing air mass. The larger the air mass, the larger the cooling down of the heating element is respectively the thereby created temperature difference.
The electronics that are integrated in the pluggable sensor analyzes this data and thereby allows for a precise ascertainment of the on-rushing air quantity.

Today our product portfolio consists of 302 air flow meters which cover a total of 10.455 vehicle types.