Apparatus for measuring a turning rate, particularly of a motor vehicle

Claim 1

An apparatus for measuring turning rate, said apparatus comprising a first sensor means (1) for generating at least one first sensor signal depending on the turning rate of a body based on a first measurement principle; a second sensor means (3) for generating a second sensor signal depending on the turning rate of the body based on a second measurement principle different from the first measurement principle; and means (2) for processing said at least one first sensor signal and said second sensor signal from the first and second sensor means to determine the turning rate, wherein said first sensor means (1) comprises an electronic compass including means for generating said at least one first sensor signal according to the earth's magnetic field and said second sensor means (3) includes an oscillating structure and means for generating said second sensor signal according to a Coriolis force experienced by said oscillating structure; and wherein the electronic compass includes at least two sensor components (10), each of said at least two sensor components (10) comprising at least one magnetoresistive sensor elements (19) arranged in a Wheatstone bridge (11) for detecting an X-, Y- or Z-component of the earth's magnetic field, an integrated field compensation coil (L F ) adjacent the Wheatstone bridge, a set/reset coil (L C ) adjacent the Wheatstone bridge, a preamplifier (12) with offset compensation connected across the Wheatstone bridge (11), a flip source connected to the field compensation coil and including means for generating clock pulses, a demodulator connected to the flip source and the preamplifier to receive output signals from the preamplifier and a current controller connected to the set/reset coil and the demodulator, said current controller including means for producing one of the at least one first sensor signals.

Claim 2

An apparatus for measuring turning rate, said apparatus comprising a first sensor means (1) for generating at least one first sensor signal depending on the turning rate of a body based on a first measurement principle; a second sensor means (3) for generating a second sensor signal depending on the turning rate of the body based on a second measurement principle different from the first measurement principle; and means (2) for processing said at least one first sensor signal and said second sensor signal from the first and second sensor means to determine the turning rate, wherein said first sensor means (1) comprises an electronic compass including means for generating said at least one first sensor signal according to the earth's magnetic field and said second sensor means (3) includes an oscillating structure and means for generating said second sensor signal according to a Coriolis force experienced by said oscillating structure; and wherein the electronic compass includes at least two sensor components (10), each of said at least two sensor components (10) comprising at least one magnetoresistive sensor elements (19) arranged in a Wheatstone bridge (11) for detecting an X-, Y- or Z-component of the earth's magnetic field, an integrated field compensation coil (L F ) adjacent the Wheatstone bridge, a set/reset coil (L C ) adjacent the Wheatstone bridge, a preamplifier (12) with offset compensation connected across the Wheatstone bridge (11), a flip source connected to the field compensation coil and including means for generating clock pulses, a demodulator connected to the flip source and the preamplifier to receive output signals from the preamplifier and a current controller connected to the set/reset coil and the demodulator, said current controller including means for producing one of the at least one first sensor signals.