Diaphragm for use in electro-acoustic transducer

• US 4,674,592 A
• Filed: 11/12/1985
• Issued: 06/23/1987
• Est. Priority Date: 11/14/1984
• Status: Expired due to Fees

• Current Assignee: Alpine Electronics Incorporated (Alps Alpine Co., Ltd.)
• Original Assignee: Alpine Electronics Incorporated (Alps Alpine Co., Ltd.)
• Inventors: Aoki, Shuichi, Kumagai, Katsuyoshi, Ito, Minoru, Haga, Akihiko
• Primary Examiner(s): Fuller, Benjamin R.
• Application Number:
  US06/796,896
• Time in Patent Office: 588 Days
• Field of Search: 181/157, 181/167, 181/169, 181/170, 428/64, 428/341, 428/342, 428/476.3, 428/479.3, 428/479.6
• US Class Current: 181/170
• CPC Class Codes: H04R 2307/021 Diaphragms comprising cellulose-like materials, e.g. wood, paper, linen
• CPC Class Codes: H04R 2307/025 Diaphragms comprising polymeric materials
• CPC Class Codes: H04R 2307/029 Diaphragms comprising fibres
• CPC Class Codes: H04R 7/02 characterised by the construction
• CPC Class Codes: H04R 7/125 comprising a plurality of superposed layers in contact
• CPC Class Codes: Y10T 428/21 Circular sheet or circular blank
• CPC Class Codes: Y10T 428/273 of coating
• CPC Class Codes: Y10T 428/277 Cellulosic substrate
• CPC Class Codes: Y10T 428/3175 Next to addition polymer from unsaturated monomer[s]
• CPC Class Codes: Y10T 428/31779 Next to cellulosic
• CPC Class Codes: Y10T 428/31783 Paper or wood

Abstract

A diaphragm for use in an electro-acoustic transducer comprises a diaphragm main body only or mainly composed of natural fibers, a layer formed by laminating thereover a polyamide resin and a synthetic resin coating layer further formed to the surface of the laminate layer. The diaphragm is free from pin holes, exhibits satisfactory water proofness and excellent physical properties such as sonic propagation velocity inherent to the natural fibers. It can be fabricated with ease at a good yield and can reduce the fabrication cost.

Claims

1. A diaphragm for use in an electro-acoustic transducer comprising

a diaphragm body of fabric material, said fabric material including natural fibers;

a preformed polyamide resin film having a thickness of 20-50 μ

m, said polyamide resin film laminated to said diaphragm body;

a synthetic resin layer coated upon said polyamide resin film, said synthetic resin layer being selected from the group consisting of nitrocellulose type lacquer enamel and vinyl acetate resin.