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:
Oct. 22, 2002
Filed:
Feb. 02, 2000
Edwin B. Merrick, Stow, MA (US);
Glen N. Gee, Carlsbad, CA (US);
John O'Mahony, Newcastle, Galway, IE;
John O'Dea, Knocknacarra, Galway, IE;
Other;
Abstract
The gas mixing apparatus provides the components of a breathing gas for mixing at approximately ambient atmospheric pressure, and regulates the pressure of a selected gas to approximately ambient atmospheric pressure for mixing with air at ambient atmospheric pressure. The gas mixing apparatus includes a piston disposed within a pump chamber. A flow limiting inlet controls introduction of a first selected gas such as oxygen for mixing with a second selected gas such as air. The pressure of the first selected gas is limited to an acceptable maximum pressure, so that even if a valve for admitting the first selected gas for mixing at ambient pressure fails, breathing gas will not be provided at an excessive pressure. A demand valve is alternatively provided for reducing the pressure of the first selected gas supplied before mixing, but a pressure sensor is also provided downstream of the demand valve for detecting failure of the demand valve, to shut off the supply of the first selected gas to prevent overpressurization.