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:
Aug. 09, 1977
Filed:
Apr. 30, 1976
Kazuho Ohta, Sagamihara, JA;
Fumio Matsuda, Machida, JA;
Tsutomu Tanaka, Yamato, JA;
Katsuhiro Ohnuki, Tokyo, JA;
Naotaka Miyaji, Tokyo, JA;
Hidetoshi Sato, Yamato, JA;
Victor Company of Japan, Limited, Yokohama, JA;
Abstract
An open-back type headphone comprises a driver unit for operating as a sound generating source, a case accommodating therewithin said driver unit and having a front face on the side to confront and be pressed against an ear of a listener and a back face on the side opposite that of the front face, said back face being acoustically open, an ear pad provided on said front face of the case and forming at the center thereof a front air chamber, and an attachment detachably attached to said back face of the case. The attachment has an open end communicable with the back face of the case and an internal space of a specific volume and is adapted to cover and seal the back face of the case. The attachment and said case have an attaching mechanism by which the attachment can be detachably attached to the case.