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:
Dec. 04, 1990
Filed:
Oct. 06, 1988
Heinz Wandel, WalddorfhasIach, DE;
Martin Skov, WalddorfhasIach, DE;
Moldex/Metric Products, Inc., Culver City, CA (US);
Abstract
A breathing mask is provided which comprises an exhaling valve disposed in an opening of the breathing mask wall. The exhaling valve includes a thin diaphragm which is adapted to be moved by the breathing pressure during inhaling and exhaling either towards or away from a sealing seat. To provide a less expensive breathing mask whose exhaling valve safely closes in particular in dust-particle-containing air and which nevertheless involves low opening and closing pressures, the diaphragm is provided with an arch. Air is allowed to escape over only a part of the circumference of the diaphragm, while the remaining part of the diaphragm circumference is so connected to a base member that the arching direction of the arch is at least partly reversible by the breathing pressure.