| 摘要 |
<p>PROBLEM TO BE SOLVED: To easily mount a detection block to a guide groove. SOLUTION: An engagement protrusion 32 is provided on one side surface of a detection block 30, and an engagement projection 33 is provided on the other side surface. A protrusion 25 to be engaged, where the engagement protrusion 32 is engaged, is provided at one sidewall of a guide groove 24. A projection to be engaged where the engagement projection 33 is engaged is provided at the other sidewall of the guide groove 24. Then, a retention part 27, for retaining the engagement protrusion 32 and the engagement projection 33 so that they can be engaged to or disengaged from the protrusion 25 to be engaged and the projecting part to be engaged is provided. Therefore, while the engagement protrusion 32 is engaged to the protrusion 25 to be engaged, the engagement projection 33 can be engaged to the retention part 27 by making a detection block 30 turn with the engagement part as the center.</p> |
