US4992084A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Activated charcoal filter layer for gas masks
Assignee: Individual
•
Filing: 1989-04-20
•
Granted: 1991-02-12
•
Expires: 2009-04-20
Abstract
Abstract The activated charcoal filter layer for gas masks contains a highly air-permeable, three-dimensional carrier framework essentially stable in shape, formed of wires, monofilaments or stays, to which a layer of granular, particularly spherical activated charcoal particles with a diameter of 0.1 to 1 mm is affixed. The carrier framework can be composed of wires, monofilaments or stays, the distance between them being at least twice as great as the diameter of the activated charcoal particles. The carrier framework can also be a large-pore reticulated polyurethane foam which has a weight of 20 to 60 g/l and pores with a diameter of 1.5 to 3 mm. The carrier framework can furthermore consist of wire netting or wire mesh arranged in layers, as well as of plastic or wire spirals with a length equal to and up to 10 times their diameter, or of wires or monofilaments with a length of 2 to 10 mm, which are held by twisted metal or plastic wires and project perpendicular from this axis in the shape of a spiral staircase. In spite of a very slight pressure drop, the filter performance is excellent.
Inventors
- 👤 Hasso von Blucher
- 👤 Ernest de Ruiter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:00
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/28; B01J20/28014; B01J20/28023; A; A62; A62B; A62B23/00; A62B23/02; B01J20/28002; B01J20/28004; B01J20/28011; B01J20/28016; B01J20/28019; B01J20/28042; B01J20/28045; B01J20/28054; B01J20/28057; B01J20/28078; B01J20/28085
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
81 words
An activated charcoal filter layer for gas masks, comprising a highly air-permeable, three dimensional carrier framework essentially stable in shape, formed of wires, monofilaments or stays, to which there is a affixed a layer of granular activated charcoal particles with a diameter of about 0.1 to 1 mm and in an amount of 50 to 300 g per liter, the distance between the wires, monofilaments or stays being at least twice as great as the diameter of the activated charcoal particles.
Claim 2
Dependent Claim
81 words
An activated charcoal filter layer for gas masks, comprising a highly air-permeable, three dimensional carrier framework essentially stable in shape, formed of wires, monofilaments or stays, to which there is a affixed a layer of granular activated charcoal particles with a diameter of about 0.1 to 1 mm and in an amount of 50 to 300 g per liter, the distance between the wires, monofilaments or stays being at least twice as great as the diameter of the activated charcoal particles.
Claim 3
Dependent Claim
25 words
A filter layer according to claim 1, wherein the openings or pores of the carrier framework have a diameter of about 1 to 5 mm.
Claim 4
Dependent Claim
39 words
A filter layer according to claim 1, wherein the diameter of the wires, monofilaments or stays of the carrier framework is such that there is complete coverage of the carrier framework with the activated charcoal particles affixed to it.
Claim 5
Dependent Claim
19 words
A filter layer according to claim 1, wherein the carrier framework is completely covered with the activated charcoal particles.
Claim 6
Dependent Claim
22 words
A filter layer according to claim 1, wherein the activated charcoal particles are affixed to the carrier framework with an adhesive mass.
Claim 7
Dependent Claim
30 words
A filter layer according to claim 5, wherein the adhesive mass is a polymer of an acrylic acid derivative, a polyurethane, a polystyrene, a polyvinyl acetate or a hotmelt glue.
Claim 8
Dependent Claim
28 words
A filter layer according to claim 5, wherein the adhesive mass comprises a polymer which can be cross-linked and which passes through a viscosity minimum before being cross-linked.
Claim 9
Dependent Claim
19 words
A filter layer according to claim 5, wherein the adhesive mass comprises an inorganic mixture which can be melted.
Claim 10
Dependent Claim
24 words
A filter layer according to claim 1, wherein the activated charcoal particles have an internal surface of about 600 to 2000 m 2 /g.
Claim 11
Dependent Claim
14 words
A filter layer according to claim 1, wherein the activated charcoal particles are pressure-resistant.
Claim 12
Dependent Claim
17 words
A filter layer according to claim 1, wherein the activated charcoal particles are highly resistant to moisture.
Claim 13
Dependent Claim
22 words
A filter layer according to claim 1, wherein the activated charcoal particles are impregnated with a salt of silver, copper or chromium.
Claim 14
Dependent Claim
15 words
A filter layer according to claim 1, wherein the activated charcoal particles contain encapsulated enzymes.
Claim 15
Dependent Claim
13 words
A filter layer according to claim 1, wherein the carrier framework is plastic.
Claim 16
Dependent Claim
17 words
A filter layer according to claim 14, wherein the carrier framework is a large-pore reticulated polyurethane foam.
Claim 17
Dependent Claim
33 words
A filter layer according to claim 15, wherein the large-pore reticulated polyurethane foam has a weight of about 20 to 60 g/l and pores with a diameter of about 1.5 to 3 mm.
Claim 18
Dependent Claim
22 words
A filter layer according to claim 1, wherein the carrier framework is formed of wire netting or wire mesh superimposed in layers.
Claim 19
Dependent Claim
29 words
A filter layer according to claim 1, wherein the carrier framework is composed of plastic or wire spirals with a length from about 1 to 10 times their diameter.
Claim 20
Dependent Claim
48 words
A filter layer according to claim 1, wherein the carrier structure is formed of wires or monofilaments with a length of about 2 to 10 mm, which are held by twisted metal or plastic wires and project perpendicular from this axis in the shape of a spiral staircase.
Claim 21
Dependent Claim
32 words
A filter layer according to claim 1, wherein the carrier structure is formed of fiber brushes which radiate out from a center point, with a length of about 2 to 10 mm.
Claim 22
Dependent Claim
24 words
A filter layer according to claim 1, wherein the carrier structures are connected with one another by heterophilic fibers or threads of hot-melt glue.
Claim 23
Dependent Claim
44 words
A filter layer according to claim 1, exhibiting a pressure drop of less than 10 mm water column at an air flow of one liter per second for a filter layer thickness of 4 cm and a circular cross-section of 100 cm 2 .
Claim 24
Dependent Claim
11 words
A hood mask including a filter layer according to claim 1.
Claim 25
Dependent Claim
19 words
A hood mask according to claim 23, wherein the filter layer is formed as a head or neck protection.
Claim 26
Dependent Claim
41 words
A gas mask including a filter layer according to claim 1 is formed in the shape of a plate, so that it can be worn on the chest or back connected with the mask element by way of a flexible hose.
Claim 27
Dependent Claim
24 words
A gas mask including a cylindrical filter element according to claim 1, with a diameter of several centimeters and arranged in a flexible hose.
Claim 28
Dependent Claim
19 words
A gas mask comprising a plurality of cylindrical filter elements according to claim 1 arranged to form a hose.
References Cited (Backward Citations)
US3374608A
Cited
US3416293A
Cited
US3713281A
Cited
US4510193A
Cited
US4510193B1
Cited
US4643182A
Cited
US4800190A
Cited
US4906263A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-02-11 | 1994-08-13 | 1995-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-11 | 1998-08-13 | 1999-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-11 | 2002-08-13 | 2003-02-12 | $7700.00 | Window Closed / Lapsed |