Claims
- 1. A two-stage electrostatic filter comprising an ionization section which is disposed in an upstream part of a throughflow passage and includes an ionization chamber in which there is mounted at least one elongated wire corona electrode which is connected to one pole of the electrical high voltage source, and a target electrode which is spaced from the corona electrode and connected to another pole of the high voltage source,
- a capacitor separator which is located in a downstream part of the throughflow passage and includes a first group and a second group of electrode elements which are arranged side-by-side in spaced-apart relationship, the electrode elements of the first group being disposed alternatively with the electrode elements of said second group and are on a different potential than the electrode elements of said second group,
- wherein,
- the electrode elements (32, 33; 132, 133) comprise an antistatic material having a surface resistivity of 10.sub.9 -10.sub.15 ohms,
- the ionization chamber (29, 129) includes a target electrode surface (37, 137; 21, 121; 132, 133) which is disposed both upstream and downstream of the corona electrode (31, 131); a distance of the corona electrode (31, 131) from the target electrode surface, when measured perpendicularly to the upstream and downstream direction of the throughflow passage (28, 128) and the longitudinal direction of the corona electrode being not less than about 4 cm and at least four times the distance between neighbouring electrode elements (32, 33; 132, 133).
- 2. An electrostatic filter according to claim 1, wherein the antistatic material is on a coating of the electrode elements.
- 3. An electrostatic filter according to claim 1, wherein the neighbouring electrode elements are adjacent to each other.
- 4. An electrostatic filter according to claim 1, wherein the electrode elements (32, 33; 132, 133) comprise an antistatic material having a surface resistivity of 10.sup.13 -10.sup.15 ohms.
- 5. An electrostatic filter according to claim 1, wherein the electrode elements (32, 33; 132, 133) comprise a dissipative material having a surface resistivity of 10.sup.13 -10.sup.15 ohms.
- 6. An electrostatic filter according to claim 1, wherein a part of the target electrode surface is formed by target electrode elements (37, 137) which are disposed on opposite sides of the corona electrode (31, 131) and which form opposing side-walls of the upstream part of the throughflow passage (28, 128).
- 7. An electrostatic filter according to claim 6, wherein a part of the target electrode surface is formed by a target electrode element (33, 132) which is arranged transversely across the throughflow passage downstream of the corona electrode (31, 131).
- 8. An electrostatic filter according to claim 6, wherein the electrode elements (32, 33; 132. 133) of the capacitor separator (30, 130) are essentially formed from a non-metallic material.
- 9. An electrostatic filter according to claim 8, wherein the non-metallic material is cellulose fibre material.
- 10. An electrostatic filter according to claim 8, wherein the non-metallic material is paperboard.
- 11. An electrostatic filter according to claim 8, wherein the non-metallic material is kraft paper.
- 12. An electrostatic filter according to claim 1, wherein a part of the target electrode surface is formed by a target electrode element (21, 121) which is arranged transversely across the throughflow passage (28, 128) upstream of the corona electrode (31, 131) and has air throughflow openings (22, 122).
- 13. An electrostatic filter according to claim 1, wherein a part of the target electrode surface is formed by a target electrode element (33, 132) which is arranged transversely across the throughflow passage downstream of the corona electrode (31, 131).
- 14. An electrostatic filter according to claim 13, wherein at least a part of the target electrode element extending transversely across the throughflow passage (28, 128) downstream of the corona electrode is formed by electrode elements (33, 132) of the capacitor separator (30, 130).
- 15. An electrostatic filter according to claim 14, wherein the electrode elements (32) of the first group are connected to a reference potential, the electrode elements (33) of the second group are electrically insulated from one another and from the electrode elements of the first group and lie at a shorter distance from the corona electrode (31) than the electrode elements of the first group; and the electrode elements of said second group extend so close to the corona electrode as to be charged to a potential in relation to the electrode elements of the first group which lies between the reference potential and the potential of the corona electrode to be not higher than about half of the potential of the corona electrode.
- 16. An electrostatic filter according to claim 15, wherein the reference potential is earth.
- 17. An electrostatic filter according to claim 1, wherein the electrode elements (32, 33; 132, 133) of the capacitor separator (30, 130) are essentially formed from a non-metallic material.
- 18. An electrostatic filter according to claim 17, wherein the electrode elements (32, 33; 132, 133) are coated with an antistatic material.
- 19. An electrostatic filter according to claim 17, where in the non-metallic material is a cellulose fibre material.
- 20. An electrostatic filter according to claim 17, wherein the non-metallic material is paperboard.
- 21. An electrostatic filter according to claim 17, wherein the non-metallic material is kraft paper.
- 22. An electrostatic filter according to claim 17, wherein the electrode elements (32, 33; 132, 133) are coated with an electrically conductive material.
- 23. An electrostatic filter according to claim 17, wherein the electrode elements (32, 33; 132, 133) are coated with a semi-conductive material.
- 24. An electrostatic filter according to claim 17, wherein the electrode elements (32, 33; 132, 133) of the capacitor separator (30, 130) are included in a part (20, 120) of the electrostatic filter which has the form of a disposable unit.
- 25. An electrostatic filter according to claim 24, wherein the disposable unit includes a housing (20, 120) which forms said throughflow passage and which is essentially comprised of a non-metallic material.
- 26. An electrostatic filter according to claim 25, wherein at least a part of the outside and inside of the housing (20, 120) is comprised of or coated with an antistatic; and in that at least a part of the target electrode surface is formed by parts (37, 137; 21, 121) of the inside of the housing, wherein those parts which form the target electrode surface and the first group of electrode elements (32, 33; 132, 133) of the capacitor separator (30, 130) are interconnected electrically through the medium of this material.
- 27. An electrostatic filter according to claim 25, wherein the opposite edges of the first group of electrode elements (32, 33; 132, 133) of the capacitor separator (30, 130) abut directly with the inner surface of the housing (20, 120) and are interconnected electrically through said inner surface; and wherein the second group of electrode elements (33, 133) of the capacitor separator are held spaced from neighbouring electrode elements (32, 132) by intermediate insulators.
- 28. An electrostatic filter according to claim 25, wherein the non-metallic material is a cellulose fibre material.
- 29. An electrostatic filter according to claim 25, wherein the non-metallic material is paperboard.
- 30. An electrostatic filter according to claim 25, wherein the non-metallic material is kraft paper.
- 31. An electrostatic filter according to claim 25, wherein at least part of the outside and inside of the housing (20, 120) is comprised of or coated with a semi-conductive material.
- 32. An electrostatic filter according to claim 1, wherein the electrode elements (32, 33; 132, 133) are formed from a semi-conductive material.
- 33. An electrostatic filter according to claim 1, wherein the electrode elements (33, 133) in the second group of electrode elements of said capacitor separator (30, 130) are provided with field strength concentrating formations.
- 34. An electrostatic filter according to claim 1, wherein a second ionization chamber (140) includes a second wire corona electrode (141) and a target electrode (142) which is spaced from the second wire corona electrode and which is electrically connected with the second group of electrode elements (133) of the capacitor separator (130), said electrode elements being insulated electrically from one another and disposed at a greater distance from the wire corona electrode (131) of the first ionization chamber (129) than the first group of electrode elements (132).
- 35. An electrostatic filter according to claim 34, wherein the second ionization chamber is disposed at or in the downstream end of the throughflow passage.
- 36. An electrostatic filter according to claims 1, wherein the electrode elements (32, 33; 132, 133) of the capacitor separator (30, 130) are essentially planar and plate-shaped and arranged in a stack, the corona electrode (31) extend generally at right angles to the planes of the electrode elements.
- 37. An electrostatic filter according to claim 1, wherein the high voltage source includes very high-ohmic current limiting resistors in the current circuit connected to the corona electrode.
- 38. An electrostatic filter according to claim 1, wherein air is transported through the filter with the aid of a fan rotor (15) which is driven by a multi-pole permanently magnetized synchronous motor; and in that a sliding clutch is provided between the fan rotor and the motor to enable the motor to start automatically.
- 39. An electrostatic filter according to claim 1, wherein the electrode elements (32, 33; 132, 133) are comprised of a high-resistive.
- 40. A two-stage electrostatic filter comprising an ionization section which is disposed in an upstream part of a throughflow passage and includes an ionization chamber in which there is mounted at least one elongated wire corona electrode which is connected to one pole of the electrical high voltage source, and a target electrode which is spaced from the corona electrode and connected to another pole of the high voltage source,
- a capacitor separator which is located in a downstream part of the throughflow passage and includes a first group and a second group of electrode elements which are arranged side-by-side in spaced-apart relationship, the electrode elements of the first group being disposed alternatively with the electrode elements of said second group and are on a different potential than the electrode elements of said second group,
- wherein,
- the electrode elements (32, 33; 132, 133) comprise a dissipative material having a surface resistivity of 10.sup.9 -10.sup.15 ohms,
- the ionization chamber (29, 129) includes a target electrode surface (37, 137; 21, 121; 132, 133) which is disposed both upstream and downstream of the corona electrode (31, 131); a distance of the corona electrode (31, 131) from the target electrode surface, when measured perpendicularly to the upstream and downstream direction of the throughflow passage (28, 128) and the longitudinal direction of the corona electrode being not less than about 4 cm and at least four times the distance between neighbouring electrode elements (32, 33; 132, 133).
- 41. An electrostatic filter according to claim 40, wherein the dissipative material is on a coating of the electrode element.
Priority Claims (1)
Number |
Date |
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9200515 |
Feb 1992 |
SEX |
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Parent Case Info
This application is a continuation of application Ser. No. 08/290,878, filed on Aug. 19, 1994, now abandoned, which was a 371 of PCT application PCT/SE93/00135, filed Feb. 19, 1993.
US Referenced Citations (4)
Foreign Referenced Citations (7)
Number |
Date |
Country |
0332624 |
Sep 1989 |
EPX |
0332624 |
Jan 1992 |
EPX |
2854742 |
Mar 1986 |
DEX |
50-60875 |
May 1975 |
JPX |
931625 |
Jul 1963 |
GBX |
1082234 |
Sep 1967 |
GBX |
8805972 |
Aug 1988 |
WOX |
Non-Patent Literature Citations (3)
Entry |
Mitsubishi Electric Corporation, drawings and specifications, Mar. 18, 1983. |
"Electrostatiska Filter;" Industrifilter, Industriel Miljo, May 17, 1994. |
"Air Filtration System--RC Type," Panasonic, Mar. 29, 1995. |
Continuations (1)
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Parent |
290878 |
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