To provide an angle sensor which can accurately detect a rotation angle of a rotating shaft, even if a surface of a rotor which rotates together in linkage with the rotation of the rotating shaft, trembles slightly.
The angle sensor 11 includes the rotor 30 which rotates together in linkage with the rotation of a steering shaft 20. The wall thickness d0 between the first principal surface 30A of the rotor 30 and the second principal surface 30B being its rear surface, is determined so that the wall thickness d0 and an angle around the axis makes a one-to-one correspondence. A magnetic sensor 41 outputs a first detection signal comprising information on the distance between the magnetic sensor 41 and the first principal surface 30A. A magnetic sensor 42 outputs a second detection signal comprising information on the distance between the magnetic sensor 42 and the second principal surface 30B. An adder 51 outputs a sum signal obtained by adding the first and second detection signals. A signal processing circuit 53 calculates a rotation angle of the steering shaft 20 based on the sum signal.
MIYAMOTO HIROKAZU
Toshifumi Onuki
Takuji Fukasawa