| 摘要 |
PURPOSE:To inhibit the genration of ratchet sound at the time of contact of a spindle and backward movement, by providing a ratchet operating mechanism which operates the ratchet from the time of the contact of the spindle with the object to be measured until the time a specified pressure is applied. CONSTITUTION:A pawl arm 46 in the ratchet operating mechaism is normally energized by an energizing spring 50 with a pawl in the direction the pawl 46a is engaged with a rack 16a. An intermediate plate 56 and the like which releaase said engagement are provided. In this constitution, when the spindle is advanced for measurement, a cam plate 26a which is attached to a scale holder is engaged with an inlined surface 46c of the arm 46, and the engagement of the pawl 46a and the rack 16a is released. Therefore, the ratchet sound is not generated when the spindle is advanced. When the spindle is contacted with the object to be measured, the engagement of cam plate 26 is released, the ratchet is engaged, a specified pressure is applied, and the measurement is performed. For release, a sliding knob 44 is moved backward to the direction of E, pushed to the direction of F, thereby rotating the intermediate plate 56 and disengaging the ratchet. Therefore the ratchet sound is not generated in the backward movement. |
