Patent US3822698A successfully refreshed from Google Patents.
US3822698A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Powered air-purifying respirator helmet
Assignee: RACAL AISTREAM Inc A CORP OF DE
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Filing: 1973-01-22
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Granted: 1974-07-09
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Expires: 1993-01-22
Abstract
Abstract A helmet or hat equipped with a built-in powered air blower and air filtering system which removes contaminants from the surrounding air and continuously delivers the purified air under positive pressure to an area between the wearers face and a fitted transparent face shield supported from the visor, and from this area the wearer breathes normally while the excess filtered air and exhaled breath escapes through a slightly restricted opening between the bottom of the mask and the wearer''s chin.
Inventors
- 👤 R Guy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:45
CPC Classifications
A; A62; A62B; A62B18/00; A62B18/04; A62B18/045; A42; A42B; A42B3/00; A42B3/04; A42B3/28; A42B3/286
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
313 words
A positive pressure filtered air respirator device comprising: a dome shaped element having a visor; a face shield having its upper edge attached and sealed to said visor, said face shield including means for engaging the side edges thereof to a wearer''s face to form seals therewith and means for permitting a slightly restrictive air passage from the lower edge thereof whereby the shield is sealed around its periphery except for a small opening adjacent the Wearer''s chin; a generally dome shaped air filter element fitted adjacently to, but slightly spaced from, the inside surface of the helmet and generally co-extensive therewith; means for securing and substantially sealing the filter element to the helmet adjacent the periphery thereof to form a first generally dome shaped space therebetween; a dome shaped impermeable member fitted adjacent to, but slightly spaced from, the underside surface of the filter element and generally co-extensive therewith; means for securing the impermeable member to the filter element and the helmet to form a second generally dome shaped space between the impermeable member and the filter element; means for providing fluid communication between the second generally dome shaped space and the interior of said shield; an electrically driven air blower secured to the helmet; means providing an inlet air passage for fluid communication between the ambient and the blower; and means providing an outlet air passage for fluid communication between the blower and the first generally dome shaped space, whereby ambient air passes through the inlet passage to the blower, through the outlet passage to the first generally dome shaped space, through the filter element to the second generally dome shaped space, to the interior of the face shield and out through the slightly restrictive air passage at the bottom of the face shield, thereby causing a slightly higher air pressure in the interior of the face shield than the ambient.
Claim 2
Dependent Claim
313 words
A positive pressure filtered air respirator device comprising: a dome shaped element having a visor; a face shield having its upper edge attached and sealed to said visor, said face shield including means for engaging the side edges thereof to a wearer''s face to form seals therewith and means for permitting a slightly restrictive air passage from the lower edge thereof whereby the shield is sealed around its periphery except for a small opening adjacent the Wearer''s chin; a generally dome shaped air filter element fitted adjacently to, but slightly spaced from, the inside surface of the helmet and generally co-extensive therewith; means for securing and substantially sealing the filter element to the helmet adjacent the periphery thereof to form a first generally dome shaped space therebetween; a dome shaped impermeable member fitted adjacent to, but slightly spaced from, the underside surface of the filter element and generally co-extensive therewith; means for securing the impermeable member to the filter element and the helmet to form a second generally dome shaped space between the impermeable member and the filter element; means for providing fluid communication between the second generally dome shaped space and the interior of said shield; an electrically driven air blower secured to the helmet; means providing an inlet air passage for fluid communication between the ambient and the blower; and means providing an outlet air passage for fluid communication between the blower and the first generally dome shaped space, whereby ambient air passes through the inlet passage to the blower, through the outlet passage to the first generally dome shaped space, through the filter element to the second generally dome shaped space, to the interior of the face shield and out through the slightly restrictive air passage at the bottom of the face shield, thereby causing a slightly higher air pressure in the interior of the face shield than the ambient.
Claim 3
Dependent Claim
91 words
A positive pressure filtered air helment according to claim 1, wherein the helmet includes a matching tapered ring integral with the peripheral edge of said impermeable liner, whereby the filtering element is secured and sealed to the helmet by positioning the impermeable liner integral with the tapered sealing ring into the helmets lower tapered edge so that the tapered sealing ring is wedged into the said tapered helmet edge with the peripheral edge of the said filter element compressed, secured and sealed between the sealing ring and the tapered helmet edge.
Claim 4
Dependent Claim
67 words
A positive pressure filtered air helmet according to claim 1 including a permeable chemical adsorption pad, wherein this permeable chemical adsorption pad is nested with and fitted just below said filter and co-extensive therewith and further has its peripheral edges sealed and secured to said helmet lower inside periphery so as to maintain a generally dome shaped space between the chemical adsorption pad and said impermeable liner.
Claim 5
Dependent Claim
41 words
A positive pressure filtered air helmet according to claim 1 wherein the impermeable liner includes protrusions spaced about on the convex side of said impermeable liner so as to maintain a generally dome shaped space between liner and said filter element.
Claim 6
Dependent Claim
159 words
A positive pressure filtered air helmet or the like according to claim 4 wherein the chemical adsorption pad is constructed from a three layer pliable and very open and even celled foamed urethane or the like, wherein the outer two of the said layers have cell openings smaller than the granules of the adsorption media such as activated carbon, which is packed into the middle layer which has cell openings larger than the adsorption granules and these cells walls are completely open so that only the thin intercell ligamentry bonds remain and the granules can be readily packed evenly throughout the middle layer, and this absorption media is held within the said middle layer by cementing the afore mentioned small cell layers so as to completely cover each side of the middle layer, and with the edges of the middle layer being sealed by lapping and cementing the smaller cell outer layers to each other all around the periphery.
Claim 7
Dependent Claim
50 words
A positive pressure filtered air helmet or the like according to claim 1 wherein the face shield is adjustable thereby allowing the wearer to swing the shield away from his face and means for releasably holding said face shield in any position within the arc of said face shield swing.
Claim 8
Dependent Claim
40 words
A positive pressure filtered air helmet or the like according to claim 1 wherein the top of the helmet crown has the electric motor mounting bracket, air intake opening, and blower housing integrally moulded as a part of the helmet.
Claim 9
Dependent Claim
73 words
A positive pressure filtered air helmet or the like according to claim 7 including a protective and decorative hollow crest with an inverted U shaped cross section removably and sealingly fastened over the blower motor mounting and blower air intake opening with said hollow crest and adjoining outer helmet surface forming an intake air passage which opens to the outside in the lower back of the helmet with the opening generally facing downward.
Claim 10
Dependent Claim
40 words
A positive pressure filtered air helment or the like according to claim 1 where in the electric motor mounting bracket and air blower housing are by themselves an integral unit which is removably sealed to and attached to said helmet.
Claim 11
Dependent Claim
78 words
A positive pressure filtered air helment of the like according to claim 1 wherein the helment is constructed and strengthened in the manner of a protective ''''hard hat'''' commonly used for worker head protection in the construction industry and wherein the electric motor and blower assembly is removably and sealingly mounted on the exterior of the helmet crown above the visor and includes means for conveying the said blower discharge air to the filter element inside the crown.
Claim 12
Dependent Claim
56 words
A positive pressure filtered air helmet or the like according to claim 10 including a relatively rigid protective cover with a plurality of air intake holes or louvers in the sides of said protective cover essentially below the level of the blower motor and said protective cover is removably and sealingly fastened over the motor-blower assembly.
References Cited (Backward Citations)
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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) | 1977-07-08 | 1978-01-07 | 1978-07-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-08 | 1982-01-07 | 1982-07-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-08 | 1986-01-07 | 1986-07-09 | $7700.00 | Window Closed / Lapsed |