Patent US4944778A successfully refreshed from Google Patents.
US4944778A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic dust collector
Assignee: Japan Science and Technology Agency
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Filing: 1987-07-13
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Granted: 1990-07-31
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Expires: 2007-07-13
Abstract
Abstract An electrostatic dust collector for removing particles, such as smoke particles, pollen and the like from a gas stream passed therethrough. The dust collector includes a filter element formed of narrow strips of pliable, porous dielectric material superimposed, face to face, with electrodes therebetween and so that no air gap is formed between the face to face strips. The superimposed strip is coiled or randomly packed into a non-conductive bag, such as of nylon net, and positioned in a gas stream from which particles are to be removed and the pores of the dielectric material are charged to attract in such gas stream to the walls of the charged pores by applying a voltage to the electrodes.
Inventors
- 👤 Motoo Yanagawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:11
CPC Classifications
B; B03; B03C; B03C3/00; B03C3/02; B03C3/04; B03C3/14; B03C3/155
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
178 words
An electrostatic dust collector comprising a filter element formed of narrow elongated strips of pliable, porous dielectric filter material having a gas barrier film on at least one surface thereof of each strip, said narrow strips and electrodes therebetween being superimposed in face to face contact, and at least on one gas barrier film and electrode therebetween and on each strip, so that said pliable, porous dielectric filter material fills the space between the gas barrier film and electrodes with no air gap exists between said face to face strips, means for applying an electrical voltage to said electrodes for forming an electrical field therebetween in the pores of said porous dielectric filter material and means for passing gas containing particles through said strips in a stream parallel to said contacting faces and said gas barrier film therebetween and through said pores of said porous material to electrically charge said particles and to attract said charged particles to a wall of said pores charged by said electrical field to remove said charged particles from said gas passing therethrough.
Claim 2
Dependent Claim
178 words
An electrostatic dust collector comprising a filter element formed of narrow elongated strips of pliable, porous dielectric filter material having a gas barrier film on at least one surface thereof of each strip, said narrow strips and electrodes therebetween being superimposed in face to face contact, and at least on one gas barrier film and electrode therebetween and on each strip, so that said pliable, porous dielectric filter material fills the space between the gas barrier film and electrodes with no air gap exists between said face to face strips, means for applying an electrical voltage to said electrodes for forming an electrical field therebetween in the pores of said porous dielectric filter material and means for passing gas containing particles through said strips in a stream parallel to said contacting faces and said gas barrier film therebetween and through said pores of said porous material to electrically charge said particles and to attract said charged particles to a wall of said pores charged by said electrical field to remove said charged particles from said gas passing therethrough.
Claim 3
Dependent Claim
56 words
An electrostatic dust collector according to claim 1, wherein said filter element is formed of three narrow elongated strips of pliable porous dielectric material superimposed, in face to face contact one on the other so that no air gap exists between said face to face strips, and said electrodes are disposed on surfaces between said strips.
Claim 4
Dependent Claim
174 words
An electrostatic dust collector wherein an electrode is formed on a gas barrier film on at least one surface of a narrow strip of a pliable porous dielectric filter material, a gas barrier film is formed over said electrode, a plurality of said narrow strips having electrodes covered by gas barrier films being superimposed one on the other so that said pliable porous dielectric filter material fills the space between the gas barrier films and electrodes with no air gap therebetween and gas is passed through said porous dielectric filter material parallel to said gas barrier films from a voltage source connected to the electrodes through respective terminal thereof is applied to the pliable porous dielectric material by said electrode to charge said particles and the walls of the pores therein and attract said charged particles and the walls of the pores therein and attract said charged particles to said charged walls and remove said attracted particles from said gas passing through said charge pliable porous dielectric material to remove particles from said gas.
Claim 5
Dependent Claim
174 words
An electrostatic dust collector wherein an electrode is formed on a gas barrier film on at least one surface of a narrow strip of a pliable porous dielectric filter material, a gas barrier film is formed over said electrode, a plurality of said narrow strips having electrodes covered by gas barrier films being superimposed one on the other so that said pliable porous dielectric filter material fills the space between the gas barrier films and electrodes with no air gap therebetween and gas is passed through said porous dielectric filter material parallel to said gas barrier films from a voltage source connected to the electrodes through respective terminal thereof is applied to the pliable porous dielectric material by said electrode to charge said particles and the walls of the pores therein and attract said charged particles and the walls of the pores therein and attract said charged particles to said charged walls and remove said attracted particles from said gas passing through said charge pliable porous dielectric material to remove particles from said gas.
Claim 6
Dependent Claim
44 words
An electrostatic dust collector according to claim 3, wherein said electrode on each said narrow strip is formed by adhering a metal film to said surface of said strip and said surface, with said metal film thereon, is coated with said gas barrier coating.
Claim 7
Dependent Claim
54 words
An electrostatic dust collector according to claim 3, wherein said electrode on each said narrow strip is formed by applying a gas barrier film to one surface of said narrow strip, a metal electrode is vaporized on said film, and said gas barrier coating is applied to said narrow strip over said metal electrode.
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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) | 1993-07-30 | 1994-01-29 | 1994-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-30 | 1998-01-29 | 1998-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-30 | 2002-01-29 | 2002-07-31 | $7700.00 | Window Closed / Lapsed |