Sensor device and electric power steering apparatus using same

A sensor device comprising:

• a first sensor part including:
• a first main sensor element configured to detect a first detection value corresponding to a first physical quantity from a detection object and to generate a first main signal based on the detected first detection value;
• a first sub sensor element configured to detect a second detection value corresponding to a second physical quantity from the detection object and to generate a first sub signal based on the detected second detection value;
• and
• a first output circuit that generates and transmits a first output signal including an ordered sequence of signals in part from the first main signal to the first sub signal;
• a second sensor part including:
• a second main sensor element configured to detect a third detection value corresponding to a third physical quantity from the detection object and to generate a second main signal based on the detected third detection value;
• a second sub sensor element configured to detect a fourth detection value corresponding to a fourth physical quantity from the detection object and to generate a second sub signal based on the detected fourth detection value;
• and
• a second output circuit that generates and transmits a second output signal including an ordered sequence of signals in part from the second main signal to the second sub signal;
• a controller including:
• a signal obtainer configured to obtain the first output signal and the second output signal;
• and
• an abnormality determiner configured to determine an abnormality based on the first output signal and the second output signal;
• a first communication line configured to connect the first sensor part and the controller and to transmit the first output signal;
• and
• a second communication line configured to connect the second sensor part and the controller and to transmit the second output signal, wherein
• the first main signal and the second sub signal are paired as a first set of signals, the first set of signals configured to increase when the first detection value and the third detection value increase, and to decrease when the first detection value and the third detection value decrease, and wherein
• the second main signal and the first sub signal are paired as a second set of signals, the second set of signals configured to increase when the second detection value and the fourth detection value increase, and to decrease when the second detection value and the fourth detection value decrease, such that the second set of signals increases when the first set of signals decreases, and such that the second set of signals decreases when the first set of signals increases, and wherein
• the first sub signal is inverted relative to the first main signal, the second sub signal is inverted relative to the second main signal, the second main signal is inverted relative to the first main signal, and the second sub signal is inverted relative to the first sub signal, and wherein
• the abnormality detector is further configured to
• detect an abnormality in the first output signal by comparing the first main signal to the first sub signal, and
• detect an abnormality in the second output signal by comparing the second main signal to the second sub signal.