SPEAKER CONE SURFACE DESIGN WITH COONS PATCH

摘要

Speaker cone is a cone-like surface, formed by an upside curve: a full circle used to link speaker coil, and a downside curve: a closed curve joined by lines and arcs used to link speaker frame. The profiles of the cone have four curves that formed by some joined arcs. Speaker cone surface may construct by lofting method and the profiles used to control the shape of the cone side. Generally, the end of the profiles does not join with the connect point of the line and arc of the upside curve. The process to modify the shape of cone surface to make it good is very complex in 3D CAD software. The shape of the speaker cone surface can be effect the character of the speaker such as the base frequency and the frequency response. The study of the geometric model of the speaker cone is needed to make the speaker cone surface to meet the user demand. In this paper, an extended Coons patch is presented to interpolate four boundaries and an inner curve simultaneous. The cone surface is pieced together with extended Coons patch. The cone profile curve act as inner curve of the extended Coons patch and the shape of the cone side will be controlling by the common boundaries of the pieced extended Coons patches. The definition and construction method of the common boundary curves are also analysis in this paper.