Steering angle detecting apparatus for motor vehicles based on the phase difference between a steering angle detection signal and steering angle estimated signal

A steering angle detecting apparatus for a motor vehicle, comprising:

• turning angle detecting means for detecting a phase of a turning angle of said steering wheel and for outputting a signal indicative of the detected steering wheel turning angle;
• speed difference detecting means for detecting a difference in speed between left and right wheels of said motor vehicle and for outputting a signal indicative of the detected speed difference therebetween;
• estimation means for estimating a steering wheel turning angle on the basis of the speed difference signal from said speed difference detecting means and for outputting a signal representative of the estimated steering wheel turning angle;
• first correction means, responsive to the signals from said turning angle detecting means and said estimation means, for correcting the phase of the turning angle detected by said turning angle detecting means to compensate for a phase difference between the turning angle signal outputted from said turning angle detecting means and the estimation turning angle signal outputted from said estimation means;
• and
• second correction means for correcting the turning angle detected by said turning angle detecting means on the basis of the turning angle corrected in phase by said first correction means and the turning angle estimated by said estimation means.