Diaphragm, spherical-shell diaphragm and electroacoustic transducer, and method of manufacturing electroacoustic transducer

A spherical shell diaphragm, comprising:

• a plurality of diaphragms with a regular n-gonal shape which is inscribed in a circle with one diameter, where n is an integer of 4 or more, said plurality of diaphragms being formed into a nearly spherical shape by linking together outer shape sections of said plurality of diaphragms,
• wherein each of said plurality of diaphragms includes;
• n number of top portions that are provided respectively within n number of triangles obtained by dividing said regular n-gonal shape with line segments connecting the center of said regular n-gonal shape and the vertices of said regular n-gonal shape, wherein each line segment obtained by connecting said top portions with vertices and said center is formed to be a ridge line;
• wherein said n-number of top portions are on an outer periphery line of a shape rotationally symmetric about the central axis of said regular n-gonal shape.

A method of manufacturing an electroacoustic transducer, comprising:

• forming, from a diaphragm material, a plurality of diaphragm segments with an outer shape section having a shape of a regular pentagon such that the regular pentagon is inscribed in a circle with one diameter;
• arranging the plurality of diaphragm segments on a plane to, in turn, bond a side of one of the plurality of said diaphragm segments and a side of another one of the plurality of said diaphragm together on the plane through a flexible linking member by positioning both vertices of the side of the one and both vertices of the side of the another one;
• fastening a plurality of driving sections which respectively have a voice coil bobbin, and vibrating said plurality of diaphragm segments, respectively, to each surface of a base with an outer shape of a regular dodecahedron in such a way that each of said voice coil bobbins extends in a direction intersecting perpendicularly to each of said surfaces of said regular dodecahedron;
• and
• fastening said plurality of voice coil bobbins to the inside surfaces of said plurality of diaphragm segments, respectively, wherein
• said plurality of diaphragm segments comprise:
• an inner shape section which protrudes in one direction with regard to a plane including said outer shape section, wherein a shape formed by projecting said inner shape section on said plane is rotationally symmetric about the central axis of said circle with the one diameter;
• and
• a vibrating face section that links said outer shape section and said inner shape section and has an inclined face inclined to said central axis,
• wherein any one of cross-sectional shapes of said vibrating face section is rotationally symmetric about an eccentric axis which is eccentric with regard to said central axis, said cross-sectional shapes being defined by a plane intersecting perpendicularly to said central axis.

The A method of manufacturing an electroacoustic transducer, comprising:

• forming, from a diaphragm material, a plurality of diaphragm segments with an outer shape section having a shape of a regular pentagon such that the regular pentagon is inscribed in a circle with one diameter;
• arranging the plurality of diaphragm segments on a plane to, in turn, bond a side of one of the plurality of said diaphragm segments and a side of another one of the plurality of said diaphragm together on the plane through a flexible linking member by positioning both vertices of the side of the one and both vertices of the side of the another one;
• fastening a plurality of driving sections which respectively have a voice coil bobbin, and vibrate said plurality of diaphragm segments, respectively, to each surface of a base with an outer shape of a regular dodecahedron in such a way that each of said voice coil bobbins extends in a direction intersecting perpendicularly to each of said surfaces of said regular dodecahedron;
• and
• fastening said plurality of voice coil bobbins to the inside surfaces of said plurality of diaphragm segments, respectively, wherein
• each of said plurality of diaphragm segments comprises:
• an outer shape section with a regular n-gonal shape which is inscribed in a circle with one diameter, where n is an integer of 4 or more;
• n number of top portions that are provided respectively within n number of triangles obtained by dividing said regular n-gonal shape with line segments connecting the center of said regular n-gonal shape and the vertices of said regular n-gonal shape, wherein each line segment obtained by connecting said top portions with vertices and said center is formed to be a ridge line;
• and
• said n-number of top portions are on an outer periphery line of a shape with rotational symmetry about an eccentric axis which is eccentric with regard to the central axis of said regular n-gonal shape.