| 摘要 |
<p>An absolute type of position-detecting apparatus is provided with a main shaft (22) which can be connected to a rotary member of a system being measured, such as a moving element in a numerically-controlled machine tool or an industrial robot, and a housing (28) rotatably supporting the main shaft (22). A reduction gear (30) with an input shaft (32) connected to the main shaft (22), and an output shaft (34) which rotates in a linked relationship with the input shaft (22) at a predetermined reduction gear ratio with respect to the input shaft (22) are provided in the housing (28). A first rotational angle detector which outputs a signal corresponding to the rotational angular position of the output shaft (34) of the reduction gear, within one full revolution of the output shaft (34) is provided between the housing (28) and the output shaft (34) of the reduction gear (30). A second rotational angle position detector which outputs a signal corresponding to the rotational angular position of the main shaft (22) within one full revolution of the main shaft (22) is provided between the main shaft (22) and the housing (28). The first and second rotational angular detectors are preferably constituted by bipolar and multipolar resolvers (48, 68), respectively. The second rotational angular detector may be constituted by an absolute type of rotary encoder (88). </p> |
