| 摘要 |
<p>PROBLEM TO BE SOLVED: To enable connecting fixation of the circumferential edge of a shell into the connecting groove of a frame securely and in good workability, and easy visual recognition of caulking conditions by the shell connecting groove each time. SOLUTION: Circumferential edges 11 of a shell 1 are each inserted into a shell connecting groove 21 formed on one side of a frame 2, and side walls 21a, 21b of the shell connecting groove are caulked so as to hold the circumferential edge of the shell between the walls, while staples 3 are provided at suitable intervals on the circumferential edge 11 of the shell 1, and the circumferential edge 11 is caulkingly clamped including the staples 3 between the side walls 21a, 21b of the shell connecting groove 21.</p> |
