Angular position measuring device

A method of designing an angular position measuring device (20) comprising a magnetic sensor (10) using magnetoresistive elements comprising exactly two Wheatstone bridges, cooperating with a moving magnetic element (12) rotating above the sensor, to measure a first and a second measurement signal (Sin, Cos) respectively proportional to the sine and the cosine of twice the angular position (α) of the moving magnetic element and to calculate a response (Arctan) corresponding to the angular position of the moving magnetic element from said first and second measurement signals, said method comprising a step of:

• offsetting the magnetic sensor (10) relative to an axis (14) of the moving magnetic element;
• and
• offsetting the moving magnetic element (12) relative to a rotation axis (30) of said moving magnetic element,
• wherein the offset values (Angle_R, Distance_R, Angle_A, Distance_A) are selected so that the angular measurement range of the magnetic sensor extends beyond 180°, and
• wherein the response (Arctan) corresponding to the angular position of the moving magnetic element is calculated from the first and second measurement signals without measurement signals from any further Wheatstone bridges.

An angular position measuring device (20) comprising:

• a moving magnetic element (12) for which a rotation angle is to be measured, the moving magnet element having an axis (14) and a rotation axis (30), the axis (14) of the moving element (12) and the rotation axis (30) being different and offset from each other;
• a magnetic sensor (10) double offset from and cooperating with the moving magnetic element (12), the magnetic sensor comprising exactly two Whetstone bridges arranged as
• i) a first Wheatstone bridge supplying a first measurement signal (Sin) proportional to the sine of twice the angular position (α) of the moving magnetic element, and
• ii) a second Wheatstone bridge supplying a second measurement signal (Cos) proportional to the cosine of twice the angular position (α) of the moving magnetic element;
• and
• a processing unit supplying a response (Arctan) corresponding to the angular position of the moving magnetic element from said first and second measurement signals,
• wherein the magnetic sensor (10) is arranged with a first offset relative to an axis (14) of the moving magnetic element and the moving magnetic element (12) is arranged a second offset relative to a rotation axis (30) of said moving magnetic element, the first and second offset values (Angle_R, Distance_R, Angle_A, Distance_A) providing an angular measurement range of the magnetic sensor extending beyond 180°, and
• wherein the processing unit supplies the response (Arctan) corresponding to the angular position of the moving magnetic element from said first and second measurement signals of said first and second Wheatstone bridges without measurement signals from any further Wheatstone bridges.