method and device for determining the massendurchsatzes a pouring medium, in particular the luftmassendurchsatzes, from a brennkraftmaschine during combustion processes is needed

摘要

A method and a device for carrying out the method are proposed for determining the mass flow rate of a flowing medium, in particular the air mass flow rate needed in the combustion process of an internal combustion engine, using a bridge circuit containing at least one temperature-dependent resistor exposed to the flowing medium. A regulating device for keeping the temperature of the temperature-dependent resistor constant is also proposed. Provision is made for switching the regulating device from the constant-temperature mode to the constant-current mode in the low mass flow rate range of the flowing medium. This measure results in an appreciable extension of the measurement range of the regulating device output voltage and an increase in the relative sensitivity. The device is so designed that the switch-over point between these two different regulating modes can be freely chosen and the switch-over operation takes place automatically. IMAGE