Gas flow control valves
US5501213A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 20, 1994 |
| Grant date | Mar 26, 1996 |
| Priority date | — |
| Expiry date | Sep 20, 2014 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB63C11/2227
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A positive pressure demand valve for breathing apparatus incorporates a tubular "balanced piston" valve member for regulating the flow of breathing gas from an inlet to an outlet. A coaxial tension spring acts to bias the valve member open and a lever coupled to a pressure-responsive diaphragm acts to push the valve member closed when a predetermined pressure is attained within the outlet. A combined pressure-relief and bypass valve member enables the operation of the main valve member to be bypassed by porting gas through the center of the main valve seat. A "first breath" mechanism is provided comprising a hooked link which can be pressed in by a button to maintain the main valve member closed and can be released by contact by the diaphragm when a negative pressure is applied to the outlet. The outlet is in the form of a bayonet connector which is locked into a corresponding inlet fitting on the user's mask by means of the same button.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.