Air mass meter with a sensor element

摘要

An air mass meter has a sensor element, across which an air mass flow to be measured moves. The sensor element is a micro-electro-mechanical system having a membrane, on which a heating element is formed. An electrical measuring resistor and at least two electrical comparison resistors are arranged upstream and downstream of the heating element. A first temperature sensor element is formed with a measuring resistor upstream of the heating element and two comparison resistors arranged downstream of the heating element. The second temperature sensor element is formed with a measuring resistor arranged downstream of the heating element and two comparison resistors arranged upstream of the heating element.

主权项

1. An air mass meter (2) comprising:
a sensor element (15) configured such that an air mass flow (10) to be measured moves over the sensor element (15), the sensor element (15) comprising a microelectromechanical system, the sensor element (15) having:
a diaphragm (17);a heating element (12) arranged on the diaphragm;a first resistor group comprising one electrical measuring resistor (22) and at least two electrical comparison resistors (21), the first resistor group being arranged on the diaphragm upstream of the heating element (12) in the direction of the air mass flow (10);a second resistor group comprising one electrical measuring resistor (22) and at least two electrical comparison resistors (21), the second resistor group being arranged on the diaphragm downstream of the heating element (12) in the direction of the air mass flow (10);a first temperature sensor element (7); anda second temperature sensor element (8), wherein the first and second temperature sensor elements are formed by electrical connection of, in each case, one measuring resistor (22) and at least two comparison resistors (21), the first temperature sensor element (7) comprising a series circuit having a measuring resistor (22) from the first resistor group, and two comparison resistors (21) from the second resistor group, and the second temperature sensor element (8) comprising a series circuit having a measuring resistor (22) from the second resistor group, and two comparison resistors (21) from the first resistor group.