| 摘要 |
PURPOSE:To miniaturize the device and reduce the cost by providing both the incremental type pattern section for generating a pulse train that is proportional to rotation angle and the absolute type pattern section for generating the absolute value of rotation angle. CONSTITUTION:When a rotary encoder that uses a code plate that has an incremental type pattern A that is provided with slits with equal distance between th neighbouring slits, and an absolute type pattern B that consists of, for example, five channels is applied to detecting the absolute value of rotation for the synchonous motor in the servo mechanism of a machine tool, the resolution of the whole encoder is determined by the resolution based on the slit distance of the incremental type pattern A, and it is enough that the absolute type pattern B determines rough absolute value. Accordingly the number of the channels of the absolute type pattern B can be made relatively small, and the size of the encoder can be made small with low cost. |
