Self contained breathing apparatus
US6401714B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 7, 1999 |
| Grant date | Jun 11, 2002 |
| Priority date | — |
| Expiry date | Apr 7, 2019 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA62B9/00
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A self contained breathing apparatus includes a pressure vessel which holds a supply of breathing air. The pressure vessel is in fluid communication through a first stage pressure regulator with a second stage breathing regulator. The breathing regulator is operatively connected to a user face mask. When the pressure available in the supply is at a suitable pressure, the pressure regulator provides pressure to breathing regulator at a first pressure. When the pressure in the supply falls to a value indicative of impending depletion of the air supply, a transfer piston in a step up vale shifts. A change in condition of the step up valve causes a step up piston to increase the output pressure from regulator. This increased pressure moves a sensing piston and causes indicating devices in an alarm circuit to be activated. In alternative embodiments, an electronic alarm module may be used.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.