Manufacture for acoustic diaphragm plate

Abstract

Abstract PURPOSE:To enable to form diaphragm plate having greater specific modulus of elasticity and internal loss, by carbonizing the mixture of crude oil separated pitch and graphite powder. CONSTITUTION:Crude oil separated pitch and graphite powder are mixed, and it is pressed into desired diaphragm plate shape. Next, this mold is heated in air for surface oxidation and at the next process, is made nonfusible to avoid deformation. Next, the mold via the nonfusible process is heated under nonoxidative atmosphere such as nitrogen or argon gas for carbonization. Thus, the diaphragm plate having greater specific modulus of elasticity and internal loss can be formed in a simple process. Further, by using liquidified crude oil separation pitch, the specific modulus of elasticity can further be increased.

Inventors

• 👤 Nobuhiro Tsukagoshi
• 👤 Teruo Toma
• 👤 Shinichi Yokozeki
• 👤 Toshikazu Yoshino
• 👤 Yasuhiro Arai

Bibliographic Details