| 摘要 |
PROBLEM TO BE SOLVED: To reduce factors for changing measuring accuracy by directly detecting a magnetic pole position of a mobile part and linear movement thereof. SOLUTION: A transmission part and a light shielding part on the position detecting side are passed between a projection part and a photodetecting part of two photo interrupters 1a and 1b so that outputs of the photo interrupters 1a and 1b are turned ON or OFF to obtain pulses of a phase (a) and a phase (b), which allows the detecting of a moving value and a moving speed of a linear synchronous motor 4. In addition, a transmission part of light made larger than the length of one magnetic pole and a magnetic pole detection side of a slit plate 3 as light shielding part formed at a part other than the transmission part are passed between projection parts and photodetecting parts of three photo interrupters 2a, 2b and 2c arranged with a phase difference of 120 deg. at each pitch of the magnetic pole of the linear motor 4. For example in the case of the linear synchronous motor 4 having three phases of armature windings at the mobile part, it can be detected that any of windings (u), (v) and (w) exists at an operation position of the photo interrupters thereby helping accomplish smooth movement. |
