| 摘要 |
PURPOSE:To improve the part storing efficiency of an acoustic equipment while making low-frequency rolling hard to occur, by providing rib which extends from a rectangular diaphragm to a frame to an edge part in a short side direction close to a voice coil driving part. CONSTITUTION:In general, when the opposite sides are equal in stiffness, large force is applied to edge part in the short-side direction close to the voice coil 8, so large amplitude is obtained. This example features plural ribs 11 provided at the edge part in the short-side direction, so the edge part at the side of the voice coil 8 increases in stiffness and becomes harder than the opposite edge part, so that it hardly moves. Therefore, nearly equal amplitude is obtained and the low frequency rolling is hard to occur regardless of distance from the voice coil 8 even by driving force eccentric with a rectangular plane diaphragm 1. |
