US3683907A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fresh air respirator
Assignee: MSA Safety Inc
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Filing: 1970-07-20
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Granted: 1972-08-15
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Expires: 1990-07-20
Abstract
Abstract A cup contains a porous member that is spaced from its bottom wall to form an air chamber behind the porous member. The cup has an opening communicating with the chamber and there is means for supporting the cup in front of a person''s nose and mouth with the porous member facing them. A stream of air is conducted to the cup opening to maintain the chamber full of air under pressure so that air will diffuse through the porous member and issue therefrom to provide fresh air around the nose and mouth.
Inventors
- 👤 Harry N Cotabish
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:11
CPC Classifications
A; A62; A62B; A62B7/00; A62B7/12; A62B18/00; A62B18/003
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
133 words
A fresh air respirator comprising a cup having a bottom wall surrounded by a side wall, the side of the cup opposite said bottom wall being open, a porous member mounted in the cup and spaced from its bottom wall to form an air chamber behind said member, a wall of the cup being provided with an opening communicating with said chamber, arm means connectable to a headgear for supporting the cup spaced in front of a person''s nose and mouth with the exposed side of the porous member facing them and open to the atmosphere, and means for continually delivering a stream of air to said cup opening to maintain said chamber full of air under pressure, whereby air will diffuse through the porous member and issue therefrom directly into the atmosphere.
Claim 2
Dependent Claim
133 words
A fresh air respirator comprising a cup having a bottom wall surrounded by a side wall, the side of the cup opposite said bottom wall being open, a porous member mounted in the cup and spaced from its bottom wall to form an air chamber behind said member, a wall of the cup being provided with an opening communicating with said chamber, arm means connectable to a headgear for supporting the cup spaced in front of a person''s nose and mouth with the exposed side of the porous member facing them and open to the atmosphere, and means for continually delivering a stream of air to said cup opening to maintain said chamber full of air under pressure, whereby air will diffuse through the porous member and issue therefrom directly into the atmosphere.
Claim 3
Dependent Claim
16 words
A respirator according to claim 1, in which said block is an open cell foamed plastic.
Claim 4
Dependent Claim
61 words
A respirator according to claim 1, in which said supporting means includes an arm provided at one end with a longitudinal slot, means at the opposite end of the arm for connecting it to headgear, and means extending through said slot connecting one side of the cup to the arm, said last-mentioned means being adjustable along the slot and rotatable therein.
Claim 5
Dependent Claim
88 words
A respirator according to claim 1, in which said supporting means include a pair of laterally spaced inclined arms provided at their lower ends with longitudinal slots, means at the upper ends of the arms for connecting them to headgear, trunnions projecting from opposite sides of the cup through said slots, said trunnions being rotatable in the slots and slidable lengthwise thereof, and nuts screwed on the outer ends of the trunnions and against said arms to lock the cup in a desired position relative to the arms.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-15 | 1976-02-14 | 1976-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-15 | 1980-02-14 | 1980-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-15 | 1984-02-14 | 1984-08-15 | $7700.00 | Window Closed / Lapsed |