Electro-acoustic transducer
AssigneeNippon Gakki Seizo Kabushiki Kaisha
InventorsAkira Nakamura, Takao Nakaya
Life of this patent
Estimating the term…
Abstract
In an electro-acoustic transducer in a loud speaker and like devices, a diaphragm and/or a voice coil bobbin is or are formed by a composite material consisting of a foamed resin containing reinforcing fibers. Such diaphragm has a large Young's modulus-to-density ratio E/.rho., a large internal loss tan.delta. and a large flexural rigidity E.I, and thus it exhibits good characteristics in sound reproducing. Such voice coil bobbin which is an electric insulator can have a small thickness and is light in weight and has a large mechanical strength, and thus it is free from adversely affecting the vibration of the diaphragm, and accordingly, the sound reproduced.
Claims25
An electro-acoustic transducer, comprising:
- a vibration system having a diaphragm, a voice coil bobbin and a voice coil wound about the bobbin;
- a magnetic circuit system forming a magnetic gap in which is positioned said voice coil;
- and
- a frame supporting, via a suspension member, said diaphragm,
- wherein at least one of the constituent members of said vibration system is comprised of a composite material of cellular plastics and reinforcing fibers integral with the cellular plastics.
An electro-acoustic transducer, comprising:
- a vibration system having a diaphragm and a voice coil bobbin wound with a voice coil;
- a magnetic circuit system forming a magnetic gap in which is positioned said voice coil;
- and
- a frame supporting, via a suspension member, said diaphragm,
- said diaphragm employing a composite material prepared with cellular plastics and its reinforcing fibers for constructing at least one constituent member of said diaphragm;
- wherein said diaphragm has a sandwich structure formed with a core member and at least one skin member bonded to a surface of said core member, and wherein said skin member is prepared with said composite material.
An electro-acoustic transducer, comprising:
- a vibration system having a diaphragm and a voice coil bobbin wound with a voice coil;
- a magnetic circuit system forming a magnetic gap in which is positioned said voice coil;
- and
- a frame supporting, via a suspension member, said diaphragm,
- said diaphragm employing a composite material prepared with cellular plastics and its reinforcing fibers for constructing at least one constituent member of said diaphragm;
- wherein said diaphragm has a sandwich structure formed with a core member and at least one skin member bonded to a surface of said core member, said core member being prepared with said composite material, and said skin member being prepared with a fiber-reinforced plastics reinforced by fibers selected from the group consisting of carbon fibers, glass fibers and aromatic polyamide fibers.
An electro-acoustic transducer, comprising:
- a vibration system having a diaphragm and a voice coil bobbin wound with a voice coil;
- a magnetic circuit system forming a magnetic gap in which is positioned said voice coil;
- and
- a frame supporting, via a suspension member, said diaphragm,
- said diaphragm employing a composite material prepared with cellular plastics and its reinforcing fibers for constructing at least one constituent member of said diaphragm;
- wherein said diaphragm has a sandwich structure formed with a core member and at least one skin member bonded to a surface of said core member, said core member being prepared with said composite material, and said skin member being prepared with a ceramics selected from the group consisting of beryllium oxide, magnesium oxide, alumina and silicon dioxide.
Dependencies are inferred from the claim text.