Angle detecting method for bending machine, angle detecting device and angle sensor for bending machine

摘要

An angle detecting method for a bending machine for detecting a bending angle of a bent work, an angle detecting device and an angle sensor are provided. While the angle sensor 3 is rotated in the forward and reverse directions, the light is detected from the light source 9 to the work W, and the plurality of optical sensors 11 and 13 disposed at the symmetrical position about the light source 9 receive the reflected light from the object W, and the amount of received light is detected by the rotation angle detector The angle calculation unit 35 calculates the angle of the object W based on the rotation angle of the angle sensor 3 corresponding to the peak value and the peak value of the data of the received light amount, and the angle of the object W is calculated in synchronism with the rotation angle of the angle sensor 3. Alternatively, the rotation angle detector 3 detects the turning angle of the angle sensor 3 when the light receiving amount of the pair of optical sensors 11 and 13 becomes equal to each other, and the angle calculating section 33 calculates the angle of the object W to be measured based on the rotation angle.