The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 28, 1982
Filed:
Nov. 28, 1979
Applicant:
Inventors:
Isao Yamamuro, Tokorozawa, JP;
Tsunehiro Tsukagoshi, Ohmori-nishi, JP;
Assignee:
Pioneer Electronic Corporation, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G10K / ;
U.S. Cl.
CPC ...
181170 ; 428408 ;
Abstract
A honeycomb shaped diaphragm for use in acoustic instruments such as speakers is manufactured by kneading a mixture of flaky graphite powder and thermoplastic resin, preferably polyvinyl chloride, rolling the mixture into a plate, forming honeycomb recesses in the plate, and mating two recessed plates with each other so that the corresponding recesses form closed cavities. The formed plate may be carbonized before assembly. The resultant diaphragm shows a high Young's modulus, a low apparent density and a remarkably high specific modulus of elasticity ensuring improved acoustic characteristics.