| 摘要 |
PURPOSE:To allow a rack and an engaging member to mate each other surely by providing a sensor a pitch interval apart from a top part of an engaging tooth and moving the sensor together with the engaging member in parallel with the rack and detecting the relative position on a basis of the measured length. CONSTITUTION:The sensor is attached in the position which is a positive integer-fold length of one pitch P of engaging tooth 8 apart from a top part 8' in the end part of engaging teeth 8 of a rack chock 9. The sensor is provided with a forward-facing sensor T1, an obliquely turned-up sensor T2, and an obliquely turned-down sensor T3. Detections due to sensors T1, T2 and T3 are started, and detected length signals t1, t2 and t3 are displayed on a video device 23, 24 and 25. It indicates the coincidence between centers of a rack tooth 7 and the engaging tooth 8 that the length from the sensor T2 to a slope 7a and the length from the sensor T3 to a slope 7b are approximately equal to each other. |
