| 摘要 |
PROBLEM TO BE SOLVED: To considerably reduce unnecessary acoustic radiation from an enclosure without increasing the weight of the enclosure. SOLUTION: The enclosure 20 employs an inner case 21 and an outer case 22 the front parts of which are formed into a cylindrical shape and the rear parts of which are formed into a semispherical shape respectively as a double case structure, and a space between them is used as a low pressure section 23 that is vacuum or nearly vacuum. A front tip 21a of the inner case 21 is formed to be a curved face and joined with a front tip 22a of the outer case 22, and an enclosure fixing reinforcing member 30 used also as a front baffle is closely fixed to the joining part 22a. A balancing spring 29 is fitted between a border of the front cylinder part and the rear spherical part of the inner case 21 and the front baffle of the enclosure fixing reinforcing member 30 or varying the diameter of the front cylinder part and the rear spherical part of the inner case 21 can form a step difference to the border between them.
|
