| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To reduce the thickness of an alarming device. <P>SOLUTION: A notch 9a is provided at a part of a cylindrical part 6 of a base 3 attached to a ceiling 2, and a pair of first engagement parts 11 having first engagement surfaces 11a formed thereon is provided at both ends of the notch 9a. A cover 22 fitted inside the cylindrical part 6 of the base 3 is provided with an elastically deformable engagement piece 23 that is engaged with the notch 9a. The engagement piece 23 is provided with second engagement parts 23a that come into sliding contact with the first engagement parts 11 and elastically deform the engagement piece 23 when the engagement piece 23 is engaged with the notch 9a. The second engagement parts are formed with second engagement surfaces 23c that come into opposed contact with the first engagement surfaces 11a when the engagement piece 23 is engaged with the notch 9a. The first and second engagement surfaces 11a and 23c are inclined so as to regulate the movement in a direction to release the engagement of the second engagement parts 23a with the first engagement parts 11. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
