Patent US4754751A successfully refreshed from Google Patents.
US4754751A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Escape respirator
Assignee: MSA Safety Inc
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Filing: 1987-06-11
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Granted: 1988-07-05
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Expires: 2007-06-11
Abstract
Abstract A self-contained emergency respirator that has a mouthpiece that fits into a wearer's mouth and which is directly connected to a chemical canister that processes exhaled breath. The mouthpiece is located within a transparent hood that completely surrounds the head of a wearer and protects the wearer from a possibly toxic environment. A breathing bag encloses the chemical canister and collects the processed exhaled breath for inhalation.
Inventors
- 👤 John W. Mausteller
- 👤 Daniel L. Thiebaud
- 👤 Miles J. McGoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:07
CPC Classifications
A; A62; A62B; A62B19/00; A62B17/00; A62B17/04; A62B9/00
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
232 words
An emergency escape respirator that is fitted over the head of a wearer and supported from a mouth thereof when used comprising: a mouthpiece having a first end and a second end; means for protecting the head of a wearer from toxic fumes, said protecting means surrounding the head of a wearer and having at least a first opening; means for processing exhalation from a wearer into oxygen, said processing means having a nozzle which is attached with the second end of the mouthpiece so exhalation passes through the mouthpiece into the processing means via the nozzle; means for collecting the oxygen, said collecting means surrounding the processing means and having at least a first opening aligned with the first opening of the protecting means so the nozzle of the processing means can be attached with the second end of the mouthpiece, the oxygen collected in the collecting means, upon inhalation by the user, passing through the processing means, through the nozzle and into the mouthpiece; and a clamp holding the second end of the mouthpiece and the nozzle in place and holding the protection means and the collecting means at their respective first openings around the second end of the mouthpiece and the nozzle; wherein the protecting means and the collecting means are capable of being collapsed into a compact form that can easily be carried by a wearer until use.
Claim 2
Dependent Claim
232 words
An emergency escape respirator that is fitted over the head of a wearer and supported from a mouth thereof when used comprising: a mouthpiece having a first end and a second end; means for protecting the head of a wearer from toxic fumes, said protecting means surrounding the head of a wearer and having at least a first opening; means for processing exhalation from a wearer into oxygen, said processing means having a nozzle which is attached with the second end of the mouthpiece so exhalation passes through the mouthpiece into the processing means via the nozzle; means for collecting the oxygen, said collecting means surrounding the processing means and having at least a first opening aligned with the first opening of the protecting means so the nozzle of the processing means can be attached with the second end of the mouthpiece, the oxygen collected in the collecting means, upon inhalation by the user, passing through the processing means, through the nozzle and into the mouthpiece; and a clamp holding the second end of the mouthpiece and the nozzle in place and holding the protection means and the collecting means at their respective first openings around the second end of the mouthpiece and the nozzle; wherein the protecting means and the collecting means are capable of being collapsed into a compact form that can easily be carried by a wearer until use.
Claim 3
Dependent Claim
72 words
An escape respirator as described in claim 1 wherein the protecting means is a transparent flexible hood that is large enough to fit over the head of a wearer, said hood having a first opening that allows the second end of the mouthpiece to communicate with the nozzle, said hood having a second opening whose size can be varied, said second opening allowing said hood to be pulled over the wearer's head.
Claim 4
Dependent Claim
16 words
An apparatus as described in claim 2 wherein the collecting means is a flexible breathing bag.
Claim 5
Dependent Claim
33 words
An apparatus as described in claim 3 wherein the breathing bag includes a vent valve positioned in and through the breathing bag to allow excess pressure in the breathing bag to be released.
Claim 6
Dependent Claim
39 words
An apparatus as described in claim 3 wherein the processing means is a canister containing a chemical that removes carbon dioxide and generates oxygen, the canister having a nozzle which is attached to the second end of the mouthpiece.
Claim 7
Dependent Claim
29 words
An apparatus as described in claim 5 including a noseclip located inside the hood and a noseclip cord attached to the noseclip and held in place by the clamp.
Claim 8
Dependent Claim
291 words
An apparatus as described in claim 5 wherein the canister is comprised of an outer shell that has a base and a circumferential wall, with the nozzle opening out from the circumferential wall; an inside shell enclosed by the outer shell, said inside shell having a circumferential wall that is flanged and a top, said inside shell having an open top face and bottom face between the wall; inside the inner shell there being a first screen resting on the bottom flange of the wall and covering the open bottom face; a first mat filter resting on and covering the first screen; a chemical processing material that removes CO 2 and generates oxygen resting on and covering the first mat filter; a second mat filter resting on and covering the chemical processing material; a second screen having a first and second side, said first side resting on and across the second mat filter and said second side covering the top face of the inner shell; and a cap that fits on and over the top of the circumferential wall, said cap being open to expose the top face of the inner shell, said cap holding the second screen in place; wherein the inner shell and cap are fitted into the outer shell with the cap held in place at the top of the outer shell so the inner shell, which is smaller than the outer shell, is supported above the base of the outer shell, thus forming an annular plenum for breath to travel from the nozzle down under the inner shell up through the first screen, through the first mat filter, through the chemical processing material, through the second mat filter, and through the second screen into the breathing bag.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-07-05 | 1992-01-04 | 1992-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-05 | 1996-01-04 | 1996-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-05 | 2000-01-04 | 2000-07-05 | $7700.00 | Window Closed / Lapsed |