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:
May. 16, 1989
Filed:
Mar. 08, 1988
Tore Palmaer, Gnosjo, SE;
Leif Palmaer, Varnamo, SE;
Finnveden Holding AB, , SE;
Abstract
A pressure ring for an earmuff, an earphone, or the like, wherein the earmuff, or the like, includes a sealing ring which is applied against the head of the wearer around the ears and the pressure ring is behind and applies pressure to the sealing ring at the top, contact surface of the pressure ring. The contact surface is taller above the base surface of the pressure ring at the peripheral outer edge of the pressure ring than at the peripheral inner edge of the pressure ring so that the sealing ring is concave and the surface of the ear cover over the ear is concave. At least the peripheral outer edge of the contact surface varies in height between the taller upper and lower ends of the pressure ring, on the one hand, and the central region of the pressure ring, on the other hand. At least one groove channel wraps at least partially around the pressure ring and extends into the pressure ring from the contact surface. Barriers in the channel block the channel from extending completely around the pressure ring. Openings communicate between adjacent concentric grooves of the channel. The barriers and openings are placed to define short-length sound traps in the channel.