US3724174A - Electrically operated dust mask - Google Patents

Electrically operated dust mask Download PDF

Info

Publication number
US3724174A
US3724174A US00076033A US3724174DA US3724174A US 3724174 A US3724174 A US 3724174A US 00076033 A US00076033 A US 00076033A US 3724174D A US3724174D A US 3724174DA US 3724174 A US3724174 A US 3724174A
Authority
US
United States
Prior art keywords
wires
electrodes
dust
filter
polarity
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00076033A
Inventor
W Walkenhorst
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bergwerksverband GmbH
Original Assignee
Bergwerksverband GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bergwerksverband GmbH filed Critical Bergwerksverband GmbH
Application granted granted Critical
Publication of US3724174A publication Critical patent/US3724174A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B03SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03CMAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/32Transportable units, e.g. for cleaning room air
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S55/00Gas separation
    • Y10S55/35Respirators and register filters

Definitions

  • ABSTRACT A breathing filter for dust filtering masks in which electrodes in the form of insulated metal wires are employed.
  • the polarity of the electrodes changes in periods which are of greater duration than the duration of dust particles in the filter, but is less than the time required for equalizing the difference in potential of the electrodes.
  • Hardly any electrical energy is used so that a source of voltage of low yield can be used.
  • the invention relates to a breathing filter for dust filtering masks for the separation of particles out of gases through a non-homogeneous electric field, which is produced with the aid of positively and negatively charged electrodes.
  • Filters according to the invention are for removing dust, above all finely divided dust, particularly out of the breathing air for the prevention of silicosis, whereby the temperature of the gases and their moisture should in principal remain without influence on the filtering effect.
  • These filters are particularly adapted for dust filtering masks in mining, in whose construction, the danger of explosion and other considerations are additionally to be considered.
  • the invention proposes to eliminate such disadvantages, and to provide a filter, particularly a breathing filter for dust filtering masks, in which for the non-homogenization of the electric field, no fibers or fibrous materials are employed.
  • Such filter makes use of the electric charges of the dust particles for the filtration operation. It prevents, however simultaneously, an accumulation of electric charges of an indication, because the polarity of the electrodes changes periodically. In view thereof, ignition of the dust or surrounding gas mixtures is prevented.
  • the filter has a relatively large free surface and accordingly a very low breathing resistance, but also has a good sound permeability.
  • the surface of the metal wires may be provided with hills and valleys for the reinforced non-homogenization of the electric field. Such hills and valleys may be produced by roughening the wire surface.
  • the metal wires are provided with an insulating coating which may consist of varnish or lacquer customarily used therefor.
  • the insulation of the metal wires is prepared moisture-repellent, where the filter is to be utilized in moist gases or gases charged with moisture.
  • FIGS. 1 to l f show, for example two individual wires and the effect attained in the filter according to FIG. 2a, where the wires are shown in cross-section. Between the wires is located an electric field.
  • FIG. 1a presumes that the left wire is charged positively and the right is charged negatively.
  • the electric field resulting between the wires is indicated with field lines, which extend from left to right.
  • the field is nonhomogeneous.
  • the non-homogeneousness results by means of the curved surface of the electrodes.
  • the insulating coating 3 which the surfaces of the electrodes 1 and 2 carry, prevents a flow of current after application of an electric voltage even then when electrically conducting particles of dust are separated in the filter so that eventually conducting bridges result between the wires.
  • the dust particles 4 are accumulated with negative charging 4 and with positive charging on the insulated wire surfaces.
  • the accumulated particles of dust change simultaneously the field between the wires, because the negative particles of dust accumulated on the wire 1 with positive polarity and the dust particles 5 with positive charging on the wire 2 diminish the field with increasing dust separation. This complete removal of the electric field between the electrodes 1 and 2 is to be prevented in the practice, and is illustrated in FIG. 1b.
  • FIG. 1c is illustrated a condition which sets in when the voltage on hand before the dust separation is disconnected and this part of the charging of the wires 1 and 2 is removed. Then there are still active solely the charges of the dust particles, which build up a field which is illustrated in dotted lines. When this field has the same strength as the starting field according to FIG. la, then its direction is solely reversed.
  • the frames 6 are layered superimposed in the filter and are held spaced from one another by elements 9. In i the embodiment by way of example, eight individual frames are present.
  • Breathing filter especially for dust masks for the separation of dust particles from gases comprising a plurali of frames arranged in supe osed relation, positive y and negatively charged e ec rodes on each frame, said electrodes comprising two similar layers of metal wires extending back and forth between the sides of each frame, the wires of one layer being charged positively and those wires of the other layer being negatively charged, a moisture-repellent insulating coating for each of said wires, each wire being of a diameter of approximately 0.1 mm.
  • the polarity of the electrodes may be changed in periods which are greater than the duration of the dust particles in the filter but less than the time required for the equalization of the potential difference of the electrodes.

Abstract

A breathing filter for dust filtering masks in which electrodes in the form of insulated metal wires are employed. The polarity of the electrodes changes in periods which are of greater duration than the duration of dust particles in the filter, but is less than the time required for equalizing the difference in potential of the electrodes. Hardly any electrical energy is used so that a source of voltage of low yield can be used.

Description

United States Patent 1 Walkenhorst [54] ELECTRICALLY OPERATED DUST MASK [75] Inventor: Wilhelm Walkenhorst, Bochum,
Germany [73] Assignee: Bergwerksverband GmbH, Essen- Kray, Germany 221 Filed: Sept. 28, 1970 [21] Appl.No.: 76,033
[52] US. Cl. ..55/123, 55/131, 55/136, 55/146, 55/155, 55/485, 55/DIG. 35 [51] Int. Cl ..B03c 3/04 [58] Field ofSearch....55/2,l55,123,131,132,143, 55/145,101,146,151,136,137, 485, DIG.
[56] References Cited UNITED STATES PATENTS 1,428,839 9/1922 Fortescue ..55/151 X 2,067,822 l/l937 Biederman .....55/131 X 2,297,601 9/1942 Williams ..55/132 2,381,455 8/1945 Jacob ..55/102 2,571,079 10/1951 Warburton ..55/131 2,804,937 9/1957 .....55/103 2,814,355 11/1957 .....55/132 12/1959 Powers ..55/132 C J O I I Q Q U I I I O Q I U 7 51 Apr. 3, 1973 2,987,137 6/1961 Brixius et al ..55/138 3,304,251 2/1967 Walker et al ..204/184 FOREIGN PATENTS OR APPLICATIONS 8,104 3/1933 Australia ..55/101 183,768 8/1922 Great Britain ..55/136 717,705 11/1954 Great Britain ..55/102 892,908 4/1962 Great Britain..... ....110/119 215,135 11/1941 Switzerland ..55/137 1,040,379 10/1958 Germany ..55/131 OTHER PUBLICATIONS German Printed Application No. 1,040,379, printed 10-2-58, (3 sheet drawing 4 pages, spec.).
Primary ExaminerDennis E. Talbert, Jr. AttorneyMalcolm W. Fraser [57] ABSTRACT A breathing filter for dust filtering masks in which electrodes in the form of insulated metal wires are employed. The polarity of the electrodes changes in periods which are of greater duration than the duration of dust particles in the filter, but is less than the time required for equalizing the difference in potential of the electrodes. Hardly any electrical energy is used so that a source of voltage of low yield can be used.
2 Claims, 8 Drawing Figures PATENTEUAPH I973 3,724,17
sum 1 'UF 2 INVENTOR [0% ei/W 7 q wm aim PAHNI'EDAPM I975 SHEET 2 OF 2 FIGZ INVENTOR MJM QJWM MMQM ELECTRICALLY OPERATED DUST MASK BACKGROUND OF THE INVENTION The invention relates to a breathing filter for dust filtering masks for the separation of particles out of gases through a non-homogeneous electric field, which is produced with the aid of positively and negatively charged electrodes.
Filters according to the invention are for removing dust, above all finely divided dust, particularly out of the breathing air for the prevention of silicosis, whereby the temperature of the gases and their moisture should in principal remain without influence on the filtering effect. These filters are particularly adapted for dust filtering masks in mining, in whose construction, the danger of explosion and other considerations are additionally to be considered.
It is known that the dust carried away by gases, particularly by air, have electrical charges, which may derive from the comminution of the dust forming material, and frequently constitute several thousand electric element charges. The polarity of the charges is different. In many cases, the charges are not distributed symmetrically, but outweigh charges of the one or the other indication. The electric separation of dust rests on the forces which an electric field exerts on the charged, and under certain circumstances also on the uncharged particles. It is superior to mechanical dust separation. In any case, when a relatively large mass of gas possesses correspondingly small dust content, the
forces to be produced for the dust separation with mechanical means must be produced through effect on the mass of gas, somewhat through acceleration.
Electrofilters with non-homogeneous electric field are likewise known per se. In breathing masks for this purpose frequently plate electrodes are provided, between which a mass of fibers for the different materials coming into question, is packed in. These fibers bring about the non-homogeneousness of the field and additionally a mechanical separation of the dust. On the other hand, the non-homogeneousness of the electric field thus attainable and therewith the degree of effectiveness of the electric separation of the dust are low. Unfavorable are the side effects of such filters deriving from the fiber packing, among them above all the relatively great breathing resistance and the low sound permeability of the filter. This has a particularly disadvantageous effect in hot and non-supervisable operations.
Additionally, in the separation of the dust, the difficulty may arise that masses of dust are of different polarity, causing a sudden electric discharge. Under certain circumstances, mixtures capable of ignition, such as a pocket of natural gas, may be ignited.
SUMMARY OF THE INVENTION The invention proposes to eliminate such disadvantages, and to provide a filter, particularly a breathing filter for dust filtering masks, in which for the non-homogenization of the electric field, no fibers or fibrous materials are employed.
In accordance with the invention, this problem is solved by constructing each electrode of metal wires with insulated surface, the metal wires having a diameter of approximately 0.1 mm. and the spacing of the metal wires of difi'erent polarity amounting to approxi- In the filters according to the invention, the filter I fibers previously used are replaced by good electrically conducting, metallic, thin wires with insulated surface. The electric voltage may amount to from 300 to 500 volts. By a good surface insulation of the wires, hardly any electrical energy is used, so that a source of voltage of very low yield and therewith of small dimensions is utilizable.
Such filter makes use of the electric charges of the dust particles for the filtration operation. It prevents, however simultaneously, an accumulation of electric charges of an indication, because the polarity of the electrodes changes periodically. In view thereof, ignition of the dust or surrounding gas mixtures is prevented. The filter has a relatively large free surface and accordingly a very low breathing resistance, but also has a good sound permeability.
The surface of the metal wires may be provided with hills and valleys for the reinforced non-homogenization of the electric field. Such hills and valleys may be produced by roughening the wire surface. The metal wires are provided with an insulating coating which may consist of varnish or lacquer customarily used therefor. The insulation of the metal wires is prepared moisture-repellent, where the filter is to be utilized in moist gases or gases charged with moisture.
The details of the inventionwill be explained more fully in the following on the basis of the figures of the drawing.
BRIEF DESCRIPTION OF THE DRAWING DESCRIPTION OF THE PREFERRED EMBODIMENT FIGS. 1 to l f show, for example two individual wires and the effect attained in the filter according to FIG. 2a, where the wires are shown in cross-section. Between the wires is located an electric field.
FIG. 1a presumes that the left wire is charged positively and the right is charged negatively. The electric field resulting between the wires is indicated with field lines, which extend from left to right. The field is nonhomogeneous. The non-homogeneousness results by means of the curved surface of the electrodes. The insulating coating 3 which the surfaces of the electrodes 1 and 2 carry, prevents a flow of current after application of an electric voltage even then when electrically conducting particles of dust are separated in the filter so that eventually conducting bridges result between the wires.
The dust particles 4 are accumulated with negative charging 4 and with positive charging on the insulated wire surfaces. The accumulated particles of dust change simultaneously the field between the wires, because the negative particles of dust accumulated on the wire 1 with positive polarity and the dust particles 5 with positive charging on the wire 2 diminish the field with increasing dust separation. This complete removal of the electric field between the electrodes 1 and 2 is to be prevented in the practice, and is illustrated in FIG. 1b.
In FIG. 1c is illustrated a condition which sets in when the voltage on hand before the dust separation is disconnected and this part of the charging of the wires 1 and 2 is removed. Then there are still active solely the charges of the dust particles, which build up a field which is illustrated in dotted lines. When this field has the same strength as the starting field according to FIG. la, then its direction is solely reversed.
If now the polarity of the electrodes is reversed, that is the electric voltage is reversed as to polarity, then there results the condition according to FIG. 1d. The wire 1 is then negative, the wire 2 is charged positively. The charging of the dust particles and the source of voltage applied accumulate. Subsequently, there results a field which is stronger than the starting field. In any case, the field weakens again with the application of further particles of dust, this being illustrated in FIG. 1e. FIG. 1 f shows the condition which fundamentally corresponds to that according to FIG. 1b, in which the particles of dust divided off on the surface of the wire exactly compensate with their charges the field applied.
The filter illustrated in FIGS. 2 and 2a utilize several individual elements. Each element consists of a frame 6, on which are wound two layers of wire 7 and 8. The wires of one layer are positive, those of the other layer are charged negatively. Negatively charged wires are illustrated solely in their circular contour, positively charged wires are illustrated by means of filled out circles. The wires which form the electrodes do not need to lie parallel to one another, that is, to be arranged like a harp, but rather, net-like arrangements are also utilizable.
The frames 6 are layered superimposed in the filter and are held spaced from one another by elements 9. In i the embodiment by way of example, eight individual frames are present.
In the illustrated filter, the period of time between two polarity changes is greater than the duration of the dust particles in the filter. It is, however, smaller than the time required for the neutralization of the electrodes through dust charges. In practice, period changes result between several seconds to several minutes.
Although the invention has been explained mainly for breathing filters for dust-filtering masks, among them chiefly for such as used in mining, the outstanding characteristics of such filters may be utilized also in other branches of industry, and filters with other dimensions may be carried out, whereby the resistance to temperature of such filters, which reaches beyond several C., still substantially increases their possibilities of use.
What I claim is:
1. Breathing filter especially for dust masks, for the separation of dust particles from gases comprising a plurali of frames arranged in supe osed relation, positive y and negatively charged e ec rodes on each frame, said electrodes comprising two similar layers of metal wires extending back and forth between the sides of each frame, the wires of one layer being charged positively and those wires of the other layer being negatively charged, a moisture-repellent insulating coating for each of said wires, each wire being of a diameter of approximately 0.1 mm. and wires of different polarity being spaced approximately 0.5 mm., hills and valleys on the surface of saidwires for the reinforced nonhomogenization of the electric field, and spacers separating one frame from another, whereby the polarity of the electrodes may be changed in periods which are greater than the duration of the dust particles in the filter but less than the time required for the equalization of the potential difference of the electrodes.
2. Breathing filter according to claim 1, in which the wire layers are harp-like in arrangement.

Claims (2)

1. Breathing filter especially for dust masks, for the separation of dust particles from gases comprising a plurality of frames arranged in superposed relation, positively and negatively charged electrodes on each frame, said electrodes comprising two similar layers of metal wires extending back and forth between the sides of each frame, the wires of one layer being charged positively and those wires of the other layer being negatively charged, a moisture-repellent insulating coating for each of said wires, each wire being of a diameter of approximately 0.1 mm. and wires of different polarity being spaced approximately 0.5 mm., hills and valleys on the surface of said wires for the reinforced non-homogenization of the electric field, and spacers separating one frame from another, whereby the polarity of the electrodes may be changed in periods which are greater than the duration of the dust particles in the filter but less than the time rEquired for the equalization of the potential difference of the electrodes.
2. Breathing filter according to claim 1, in which the wire layers are harp-like in arrangement.
US00076033A 1970-09-28 1970-09-28 Electrically operated dust mask Expired - Lifetime US3724174A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US7603370A 1970-09-28 1970-09-28

Publications (1)

Publication Number Publication Date
US3724174A true US3724174A (en) 1973-04-03

Family

ID=22129517

Family Applications (1)

Application Number Title Priority Date Filing Date
US00076033A Expired - Lifetime US3724174A (en) 1970-09-28 1970-09-28 Electrically operated dust mask

Country Status (1)

Country Link
US (1) US3724174A (en)

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3816980A (en) * 1972-03-21 1974-06-18 L Schwab Electrostatic gas filters
US3828526A (en) * 1972-10-17 1974-08-13 A King Particle collector
US3892544A (en) * 1973-07-16 1975-07-01 Crs Ind Electrodynamic electrostatic gas charge
US4215682A (en) * 1978-02-06 1980-08-05 Minnesota Mining And Manufacturing Company Melt-blown fibrous electrets
US4549887A (en) * 1983-01-04 1985-10-29 Joannou Constantinos J Electronic air filter
US4737169A (en) * 1986-04-22 1988-04-12 Bossard Peter R Electrostatic filter
US4744910A (en) * 1986-04-22 1988-05-17 Voyager Technologies, Inc. Electrostatic filter
US5143524A (en) * 1990-02-20 1992-09-01 The Scott Fetzer Company Electrostatic particle filtration
US5376168A (en) * 1990-02-20 1994-12-27 The L. D. Kichler Co. Electrostatic particle filtration
US5405434A (en) * 1990-02-20 1995-04-11 The Scott Fetzer Company Electrostatic particle filtration
US5492677A (en) * 1993-06-02 1996-02-20 Ajiawasu Kabushiki Kaisha Contaminated air purifying apparatus
US5941244A (en) * 1997-07-29 1999-08-24 Mitsumasa Chino Dustproof mask
US20040216745A1 (en) * 2003-04-30 2004-11-04 Yuen Peter Siltex Electronic human breath filtration device
US20050139217A1 (en) * 2003-12-31 2005-06-30 K. C. Chiam Respiratory mask with inserted spacer
US20070089602A1 (en) * 2005-10-25 2007-04-26 General Electric Company Electrical enhancement of fabric filter performance
EP1985371A1 (en) * 2006-02-14 2008-10-29 Kagome Co., Ltd Fungicidal method via conidium adsorption with the use of dielectric polarization, apparatus for eliminating flying organisms and apparatus for protecting plant
WO2010075958A1 (en) 2008-12-17 2010-07-08 Langner Manfred H Ionizing device for air treatment systems
WO2016176445A1 (en) * 2015-04-28 2016-11-03 BioLx, Inc. Electronic respirator mask
US10016766B2 (en) * 2016-03-24 2018-07-10 The Boeing Company Dust mitigation system utilizing conductive fibers
DE102020002271B3 (en) * 2020-04-14 2021-06-17 Heinz Günther Römer Virological respirator to protect against droplet infections

Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU8104A (en) * 1904-06-01 1905-03-21 Soia'ester Eaton William Improvements in plate printing and embossing machines
GB183768A (en) * 1921-11-16 1922-08-03 Erwin Moller Method and device for separating suspended particles from electrically insulating fluids, especially gases
US1428839A (en) * 1919-02-25 1922-09-12 Westinghouse Electric & Mfg Co Ionizing electrode for precipitating apparatus
US2067822A (en) * 1936-04-11 1937-01-12 Joseph B Biederman Mask for the prevention and relief of allergic respiratory complaints
CH215135A (en) * 1940-10-09 1941-06-15 Ventilator A G Electrostatic precipitator.
US2297601A (en) * 1940-09-03 1942-09-29 American Air Filter Co Electric gas cleaner
US2381455A (en) * 1942-10-31 1945-08-07 Carlyle W Jacob Electrical precipitation apparatus
US2571079A (en) * 1948-12-01 1951-10-09 Westinghouse Electric Corp Electrostatic precipitator
GB717705A (en) * 1951-01-10 1954-11-03 Sfindex Improvements in or relating to internal combustion engines incorporating electrostatic filters
US2804937A (en) * 1953-10-21 1957-09-03 Goodyear Tire & Rubber Air filter with orderly arranged filaments
US2814355A (en) * 1955-09-14 1957-11-26 Gen Electric Electrostatic gas filter
DE1040379B (en) * 1953-03-07 1958-10-02 Ludger Funder Dr Ing Dust protection mask with electrostatically charged filter plates
US2917130A (en) * 1957-12-11 1959-12-15 Gen Electric Electrostatic gas filter having arrangement for cancelling captured charge
US2987137A (en) * 1955-01-25 1961-06-06 Rockwell Standard Co Particle charging apparatus for electrostatic filter
GB892908A (en) * 1959-10-31 1962-04-04 Zd Y Na Vyrobu Vzduchotechnick A polarized filter element
US3304251A (en) * 1962-03-14 1967-02-14 Exxon Research Engineering Co Separation of wax from an oil dispersion using a non-uniform electric field

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU8104B (en) * 1904-06-01 1905-03-21 Soiaester Eaton William Improvements in plate printing and embossing machines

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU8104A (en) * 1904-06-01 1905-03-21 Soia'ester Eaton William Improvements in plate printing and embossing machines
US1428839A (en) * 1919-02-25 1922-09-12 Westinghouse Electric & Mfg Co Ionizing electrode for precipitating apparatus
GB183768A (en) * 1921-11-16 1922-08-03 Erwin Moller Method and device for separating suspended particles from electrically insulating fluids, especially gases
US2067822A (en) * 1936-04-11 1937-01-12 Joseph B Biederman Mask for the prevention and relief of allergic respiratory complaints
US2297601A (en) * 1940-09-03 1942-09-29 American Air Filter Co Electric gas cleaner
CH215135A (en) * 1940-10-09 1941-06-15 Ventilator A G Electrostatic precipitator.
US2381455A (en) * 1942-10-31 1945-08-07 Carlyle W Jacob Electrical precipitation apparatus
US2571079A (en) * 1948-12-01 1951-10-09 Westinghouse Electric Corp Electrostatic precipitator
GB717705A (en) * 1951-01-10 1954-11-03 Sfindex Improvements in or relating to internal combustion engines incorporating electrostatic filters
DE1040379B (en) * 1953-03-07 1958-10-02 Ludger Funder Dr Ing Dust protection mask with electrostatically charged filter plates
US2804937A (en) * 1953-10-21 1957-09-03 Goodyear Tire & Rubber Air filter with orderly arranged filaments
US2987137A (en) * 1955-01-25 1961-06-06 Rockwell Standard Co Particle charging apparatus for electrostatic filter
US2814355A (en) * 1955-09-14 1957-11-26 Gen Electric Electrostatic gas filter
US2917130A (en) * 1957-12-11 1959-12-15 Gen Electric Electrostatic gas filter having arrangement for cancelling captured charge
GB892908A (en) * 1959-10-31 1962-04-04 Zd Y Na Vyrobu Vzduchotechnick A polarized filter element
US3304251A (en) * 1962-03-14 1967-02-14 Exxon Research Engineering Co Separation of wax from an oil dispersion using a non-uniform electric field

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
German Printed Application No. 1,040,379, printed 10 2 58, (3 sheet drawing 4 pages, spec.). *

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3816980A (en) * 1972-03-21 1974-06-18 L Schwab Electrostatic gas filters
US3828526A (en) * 1972-10-17 1974-08-13 A King Particle collector
US3892544A (en) * 1973-07-16 1975-07-01 Crs Ind Electrodynamic electrostatic gas charge
US4215682A (en) * 1978-02-06 1980-08-05 Minnesota Mining And Manufacturing Company Melt-blown fibrous electrets
US4549887A (en) * 1983-01-04 1985-10-29 Joannou Constantinos J Electronic air filter
US4737169A (en) * 1986-04-22 1988-04-12 Bossard Peter R Electrostatic filter
US4744910A (en) * 1986-04-22 1988-05-17 Voyager Technologies, Inc. Electrostatic filter
US5143524A (en) * 1990-02-20 1992-09-01 The Scott Fetzer Company Electrostatic particle filtration
US5376168A (en) * 1990-02-20 1994-12-27 The L. D. Kichler Co. Electrostatic particle filtration
US5405434A (en) * 1990-02-20 1995-04-11 The Scott Fetzer Company Electrostatic particle filtration
US5492677A (en) * 1993-06-02 1996-02-20 Ajiawasu Kabushiki Kaisha Contaminated air purifying apparatus
US5941244A (en) * 1997-07-29 1999-08-24 Mitsumasa Chino Dustproof mask
US20040216745A1 (en) * 2003-04-30 2004-11-04 Yuen Peter Siltex Electronic human breath filtration device
US7392806B2 (en) * 2003-04-30 2008-07-01 Peter Siltex Yuen Electronic human breath filtration device
US20050139217A1 (en) * 2003-12-31 2005-06-30 K. C. Chiam Respiratory mask with inserted spacer
US7086401B2 (en) * 2003-12-31 2006-08-08 Megatech Scientific Pte Ltd. Respiratory mask with inserted spacer
US20070089602A1 (en) * 2005-10-25 2007-04-26 General Electric Company Electrical enhancement of fabric filter performance
EP1779917A1 (en) * 2005-10-25 2007-05-02 General Electric Company Electrical enhancement of fabric filter performance
US7294169B2 (en) 2005-10-25 2007-11-13 General Electric Company Electrical enhancement of fabric filter performance
EP1985371A1 (en) * 2006-02-14 2008-10-29 Kagome Co., Ltd Fungicidal method via conidium adsorption with the use of dielectric polarization, apparatus for eliminating flying organisms and apparatus for protecting plant
EP1985371A4 (en) * 2006-02-14 2013-05-22 Kagome Kk Fungicidal method via conidium adsorption with the use of dielectric polarization, apparatus for eliminating flying organisms and apparatus for protecting plant
WO2010075958A1 (en) 2008-12-17 2010-07-08 Langner Manfred H Ionizing device for air treatment systems
WO2016176445A1 (en) * 2015-04-28 2016-11-03 BioLx, Inc. Electronic respirator mask
US10016766B2 (en) * 2016-03-24 2018-07-10 The Boeing Company Dust mitigation system utilizing conductive fibers
DE102020002271B3 (en) * 2020-04-14 2021-06-17 Heinz Günther Römer Virological respirator to protect against droplet infections

Similar Documents

Publication Publication Date Title
US3724174A (en) Electrically operated dust mask
US2297601A (en) Electric gas cleaner
US4509958A (en) High-efficiency electrostatic filter device
GB1381783A (en) Apparatus for controlling the movement of light particles
US2822058A (en) Electrostatic precipitators
US4555252A (en) Electrostatic filter construction
US2974747A (en) Electric precipitators
DE3276458D1 (en) Method of making fibrous electrets
JPH05245412A (en) Method for dedusting gas at high temperature and apparatus for the same
US2798572A (en) Electrostatic precipitators
US3966435A (en) Electrostatic dust filter
US2888092A (en) Electrostatic gas filter
US3117849A (en) Air cleaner
US2958393A (en) Electrode system for the separator of an electric dust precipitator
DE3266399D1 (en) Electrostatic precipitators, discharge electrodes therefor and method of manufacturing the discharge electrodes
US2817413A (en) Electrostatic precipitators
JPS59145314A (en) Diesel particulate collector
KR102409978B1 (en) Electric Dust Collection Device
GB1348614A (en) Electrostatic precipitators
GB538294A (en) Apparatus for the electrical precipitation of suspended particles from gaseous fluids
JPH01249145A (en) Air filter
JPS56141854A (en) Electrostatic filter
JPS61136451A (en) Electrostatic filter apparatus
SU564883A1 (en) High-tension separator
JPS60500658A (en) Method and apparatus for producing filter media for electric filters