| 摘要 |
<p>A loudspeaker for an alarm system consists of a frusto-conical diaphragm 1 fixed at its periphery 2 to a support casing 4 and a domed diaphragm 5 placed between the casing 4 and a motor unit 11 with the domed part extending through a central opening 7 in the casing 4 and partly extending into the frusto-conical diaphragm 1, which is joined to the domed diaphragm in the region of the smaller end of the frusto- conical diaphragm, so that the dome is partially lodged in the interior of the frusto-conical diaphragm 1. <IMAGE></p> |
