US3619719A - Static eliminators - Google Patents
Static eliminators Download PDFInfo
- Publication number
- US3619719A US3619719A US832605A US3619719DA US3619719A US 3619719 A US3619719 A US 3619719A US 832605 A US832605 A US 832605A US 3619719D A US3619719D A US 3619719DA US 3619719 A US3619719 A US 3619719A
- Authority
- US
- United States
- Prior art keywords
- electrode
- cable
- chamber
- static eliminator
- wall
- 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
Links
Images
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05F—STATIC ELECTRICITY; NATURALLY-OCCURRING ELECTRICITY
- H05F3/00—Carrying-off electrostatic charges
- H05F3/04—Carrying-off electrostatic charges by means of spark gaps or other discharge devices
Definitions
- a static eliminator for blowing a stream of ionized air on to an exposed surface having a static charge to neutralize its charge and blow ofi' attracted particles comprising an electrode within an insulating sleeve through which air under pressure is passed and ionizing voltage being applied between the electrode and a metal surface hidden from the electrode by the sleeve.
- the invention relates to a static eliminator of the kind comprising means for blowing a stream of ionized air on to an exposed surface having a static charge to neutralize its charge and blow off attracted particles.
- Static eliminators of this kind which have a tube of insulating material with a central needle or electrode and through which air is blown. The exit end of the tube is surrounded by a metal ring and a high voltage is applied between this ring and the electrode.
- Such static eliminators produce corona discharge during use and there is also a substantial risk of arcing. They are therefore unsafe for operation in the presence of inflammable or explosive materials or vapors.
- An object of the present invention is to provide an improved static eliminator of the kind described which is safe for use in the presence of inflammable or explosive materials or vapors.
- a static eliminator comprises a metal chamber for receiving air under pressure and containing a needle electrode or electrodes coupled to a cable for supplying a high tension to the electrode or electrodes, the or each electrode being surrounded by a tube of insulating material which extends at least as far as the external wall of the chamber so that there is no direct discharge path between the electrode and the chamber wall, the tube having a cavity surrounding the electrode and an airhole or holes connecting the cavity to the chamber so that air is blown around the electrode under pressure.
- the or each electrode may be directly connected to the cable.
- the or each electrode may be capacitatively coupled to the cable to provide a shockless static eliminator.
- FIG. 1 is a side view of a static eliminator according to the present invention
- FIG. 2 is a section of an electrode and tube which may be used in the eliminator of FIG. 1, and
- FIG. 3 is a section of another form of electrode and tube which may be used in the eliminator of FIG. 1.
- FIG. 1 of the drawings shows a static eliminator suitable for removing static charge from printed paper or other material after processing which is contained in an elongated air box 1 adapted to fit transversely across the web.
- the box is of metal and is earthed during use, being provided with a metal lid 2 which has an airtight seal around its edges with the box.
- a high tension cable 3 in an insulating sleeve 4 extends longitudinally within the box, being led out of the box through a sealed soliddrawn conduit 5 for connection to a power unit or supply indicated at P.
- An inlet 6 is provided for the supply of air to the box from a single or multistage blower B.
- a pressure switch S may be incorporated in the power unit connected to be subject to the pressure supplied by the blower as shown in FIG. 1 to ensure that the high tension can only be applied when the air pressure in the box is above a preselected minimum value.
- tubes 7 of insulating material such as P.T.F.E.
- the high tension cable passing through transverse openings 8 formed in the lower end portions of these tubes while at their upper ends the tubes are located in holes 9 in the lid, the insulated tubes being shouldered near their upper ends and urged by a spring 10 into engagement with the lid around the holes.
- each tube there is, along the axis of each tube, a needle electrode II which is screwed into the material of the tube 7 and extends through the cable sleeve 4 to the conductor 3 of the cable.
- a needle electrode 11 is screwed into the material of the tube 7 and extends to a brass or metal tube 12 surrounding the insulating sleeve 4 of the cable and providing a shockless capacitive coupling.
- the tube shown is a ring fitting inside the opening 8 of each tube.
- the same efiect could be achieved by applying a layer of metal to the outer surface of the insulating sleeve 4.
- the upper tip 3 o the needle is a sufficient distance below the rim for electrical discharges to be avoided.
- the tubes are bored with one or more narrow airholes 14 to permit air under pressure to enter from the box into the space around the electrode and to be forced out through the tube end.
- the insulating tubes extend through the lid the electrical field must curve round the rim and there is no direct discharge path. Electrical discharges are thus inhibited and the eliminator is safe for use in the presence of inflammable or explosive materials or vapors.
- the shape of the tubes also reduces the risk of arcing due to any metallic objects entering the tube.
- the pressure switch ensures that there must be an air pressure in the air box to drive out any vapor which may have leaked back before the high tension is applied.
- the enclosure of the cable lead ensures that there can be no voltage leaks outside the air box.
- the air blower and power unit can either be isolated from the hazardous area or can be constructed from intrinsically safe components. I
- a static eliminator comprising a metal wall defining a chamber having a connection for communicating it with a source of air under pressure, said wall having at least one side opening, a high tension electric cable extending within said chamber and at least one needle electrode coupled to said cable within the chamber, a body of electrical insulating material within said chamber having a tubular portion surrounding said electrode in spaced relation therefrom and extending through said wall opening at least as far as the external surface of said wall so that there is no direct discharge path between said electrode and said wall, aperture means in said tubular portion providing communication between the interior of said chamber and said space around said electrode so that air under pressure may pass from said chamber around said electrode, a power unit for supplying electrical current to said cable, said power unit including a pressure switch which electrically disconnects the unit from the cable when the pressure of the air from the air source is below a preselected value.
Landscapes
- Elimination Of Static Electricity (AREA)
- Electrostatic Separation (AREA)
- Physical Or Chemical Processes And Apparatus (AREA)
Abstract
A static eliminator for blowing a stream of ionized air on to an exposed surface having a static charge to neutralize its charge and blow off attracted particles, the eliminator comprising an electrode within an insulating sleeve through which air under pressure is passed and ionizing voltage being applied between the electrode and a metal surface hidden from the electrode by the sleeve.
Description
United States Patent 1 Inventors John Reginald Waller;
John Richard Radington-Meech, both of London, England Appl. No. 832,605
Filed June 12, 1969 Patented Nov. 9, 1971 Assignee Industrial Electrical Company Limited London, England Priorities June 17, 1968 Great Britain 28,744/68; Feb. 28, 1969, Great Britain, No. 10,755/69 STATIC ELIMINATORS 7 Claims, 3 Drawing Figs.
US. Cl 317/2 F,
511 rm. Cl nosr 3/00 50 Field oiSearch 317/2, 2.6, 4
[5 6] References Cited UNITED STATES PATENTS 3,111,605 11/1963 Mulleretal.
Primary Examiner-lee T. Hix Att0rney-Norris & Bateman ABSTRACT: A static eliminator for blowing a stream of ionized air on to an exposed surface having a static charge to neutralize its charge and blow ofi' attracted particles, the eliminator comprising an electrode within an insulating sleeve through which air under pressure is passed and ionizing voltage being applied between the electrode and a metal surface hidden from the electrode by the sleeve.
PAIENTEnunv 9191: 3.619.719
INVENTORS JOHN REGINALD WALLER AND JOHN RICHARD RADINGTON MEECI aw a ZXlQma W The invention relates to a static eliminator of the kind comprising means for blowing a stream of ionized air on to an exposed surface having a static charge to neutralize its charge and blow off attracted particles.
Static eliminators of this kind are known which have a tube of insulating material with a central needle or electrode and through which air is blown. The exit end of the tube is surrounded by a metal ring and a high voltage is applied between this ring and the electrode. Such static eliminators produce corona discharge during use and there is also a substantial risk of arcing. They are therefore unsafe for operation in the presence of inflammable or explosive materials or vapors.
An object of the present invention is to provide an improved static eliminator of the kind described which is safe for use in the presence of inflammable or explosive materials or vapors.
To this end a static eliminator according to the present invention, comprises a metal chamber for receiving air under pressure and containing a needle electrode or electrodes coupled to a cable for supplying a high tension to the electrode or electrodes, the or each electrode being surrounded by a tube of insulating material which extends at least as far as the external wall of the chamber so that there is no direct discharge path between the electrode and the chamber wall, the tube having a cavity surrounding the electrode and an airhole or holes connecting the cavity to the chamber so that air is blown around the electrode under pressure.
The or each electrode may be directly connected to the cable. Alternatively the or each electrode may be capacitatively coupled to the cable to provide a shockless static eliminator.
Embodiments of the invention will be described with reference to the accompanying drawings in which:
FIG. 1 is a side view of a static eliminator according to the present invention,
FIG. 2 is a section of an electrode and tube which may be used in the eliminator of FIG. 1, and
FIG. 3 is a section of another form of electrode and tube which may be used in the eliminator of FIG. 1.
FIG. 1 of the drawings shows a static eliminator suitable for removing static charge from printed paper or other material after processing which is contained in an elongated air box 1 adapted to fit transversely across the web. The box is of metal and is earthed during use, being provided with a metal lid 2 which has an airtight seal around its edges with the box. A high tension cable 3 in an insulating sleeve 4 extends longitudinally within the box, being led out of the box through a sealed soliddrawn conduit 5 for connection to a power unit or supply indicated at P. An inlet 6 is provided for the supply of air to the box from a single or multistage blower B. A pressure switch S may be incorporated in the power unit connected to be subject to the pressure supplied by the blower as shown in FIG. 1 to ensure that the high tension can only be applied when the air pressure in the box is above a preselected minimum value.
At spaced intervals along the length of the box are disposed tubes 7 of insulating material, such as P.T.F.E. the high tension cable passing through transverse openings 8 formed in the lower end portions of these tubes while at their upper ends the tubes are located in holes 9 in the lid, the insulated tubes being shouldered near their upper ends and urged by a spring 10 into engagement with the lid around the holes. This arrangement gives a reasonable seal but it is not necessarily airtight.
In the embodiment shown in FIG. 2 there is, along the axis of each tube, a needle electrode II which is screwed into the material of the tube 7 and extends through the cable sleeve 4 to the conductor 3 of the cable.
In the embodiment of FIG. 3 a needle electrode 11 is screwed into the material of the tube 7 and extends to a brass or metal tube 12 surrounding the insulating sleeve 4 of the cable and providing a shockless capacitive coupling. The tube shown is a ring fitting inside the opening 8 of each tube. However, the same efiect could be achieved by applying a layer of metal to the outer surface of the insulating sleeve 4.
In both embodiments the upper tip 3 o the needle is a sufficient distance below the rim for electrical discharges to be avoided. The tubes are bored with one or more narrow airholes 14 to permit air under pressure to enter from the box into the space around the electrode and to be forced out through the tube end. A
Because the insulating tubes extend through the lid the electrical field must curve round the rim and there is no direct discharge path. Electrical discharges are thus inhibited and the eliminator is safe for use in the presence of inflammable or explosive materials or vapors. The shape of the tubes also reduces the risk of arcing due to any metallic objects entering the tube. The pressure switch ensures that there must be an air pressure in the air box to drive out any vapor which may have leaked back before the high tension is applied.
The enclosure of the cable lead ensures that there can be no voltage leaks outside the air box. The air blower and power unit can either be isolated from the hazardous area or can be constructed from intrinsically safe components. I
We claim:
l. A static eliminator comprising a metal wall defining a chamber having a connection for communicating it with a source of air under pressure, said wall having at least one side opening, a high tension electric cable extending within said chamber and at least one needle electrode coupled to said cable within the chamber, a body of electrical insulating material within said chamber having a tubular portion surrounding said electrode in spaced relation therefrom and extending through said wall opening at least as far as the external surface of said wall so that there is no direct discharge path between said electrode and said wall, aperture means in said tubular portion providing communication between the interior of said chamber and said space around said electrode so that air under pressure may pass from said chamber around said electrode, a power unit for supplying electrical current to said cable, said power unit including a pressure switch which electrically disconnects the unit from the cable when the pressure of the air from the air source is below a preselected value.
2. A static eliminator as defined in claim 1, wherein said tubular portion projects through said metal wall and has a closed bottom wherein said electrode is fixed and an open outer end for discharge of air externally of said chamber.
3. A static eliminator as recited in claim I, wherein said electrode is in contact with the cable.
4. A static eliminator as recited in claim 1, wherein said electrode is capacitatively coupled to the cable.
5. A static eliminator as recited in claim 4, wherein the electrode is in contact with a metal ring surrounding the cable.
6. A static eliminator as recited in claim I, wherein the tubular portion of insulating material extends beyond the external wall of the metal chamber.
7. A static eliminator as recited in claim 1, wherein the metal wall comprises an elongated air box and includes a row of the said electrodes coupled to the cable.
Claims (7)
1. A static eliminator comprising a metal wall defining a chamber having a connection for communicating it with a source of air under pressure, said wall having at least one side opening, a high tension electric cable extending within said chamber and at least one needle electrode coupled to said cable within the chamber, a body of electrical insulating material within said chamber having a tubular portion surrounding said electrode in spaced relation therefrom and extending through said wall opening at least as far as the external surface of said wall so that there is no direct discharge path between said electrode and said wall, aperture means in said tubular portion providing communication between the interior of said chamber and said space around said electrode so that air under pressure may pass from said chamber around said electrode, a power unit for supplying electrical current to said cable, said power unit including a pressure switch which electrically disconnects the unit from the cable when the pressure of the air from the air source is below a preselected value.
2. A static eliminator as defined in claim 1, wherein said tubular portion projects through said metal wall and has a closed bottom wherein said electrode is fixed and an open outer end for discharge of air externally of said chamber.
3. A static eliminator as recited in claim 1, wherein said electrode is in contact with the cable.
4. A static eliminator as recited in claim 1, wherein said electrode is capacitatively coupled to the cable.
5. A static eliminator as recited in claim 4, wherein the electrode is in contact with a metal ring surrounding the cable.
6. A static eliminator as recited in claim 1, wherein the tubular portion of insulating material extends beyond the external wall of the metal chaMber.
7. A static eliminator as recited in claim 1, wherein the metal wall comprises an elongated air box and includes a row of the said electrodes coupled to the cable.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB2874468 | 1968-06-17 | ||
GB1075569A GB1197132A (en) | 1968-06-17 | 1968-06-17 | Static Eliminator |
Publications (1)
Publication Number | Publication Date |
---|---|
US3619719A true US3619719A (en) | 1971-11-09 |
Family
ID=26247742
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US832605A Expired - Lifetime US3619719A (en) | 1968-06-17 | 1969-06-12 | Static eliminators |
Country Status (2)
Country | Link |
---|---|
US (1) | US3619719A (en) |
NL (1) | NL6909200A (en) |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4194232A (en) * | 1978-03-31 | 1980-03-18 | Cumming James M | Ion treatment of photographic film |
US4213167A (en) * | 1978-03-31 | 1980-07-15 | Cumming James M | Planar gas and ion distribution |
US4271451A (en) * | 1976-07-20 | 1981-06-02 | Hercules Incorporated | Method and apparatus for controlling static charges |
US4725732A (en) * | 1986-07-02 | 1988-02-16 | Xerox Corporation | Pin corotron and scorotron assembly |
US4725731A (en) * | 1986-07-02 | 1988-02-16 | Xerox Corporation | Photoreceptor deletion control by utilization of corona wind |
US5121286A (en) * | 1989-05-04 | 1992-06-09 | Collins Nelson H | Air ionizing cell |
US5125936A (en) * | 1988-06-03 | 1992-06-30 | Boliden Contech Ab | Emission electrode |
US5307234A (en) * | 1990-05-26 | 1994-04-26 | Haug Gmbh & Co. Kg | Corona discharger with counter electrode of wire coated by conductive plastic |
US5423216A (en) * | 1992-12-24 | 1995-06-13 | Shin-Etsu Chemical Co., Ltd. | Apparatus for automatically determining bulk specific gravity of powdery product |
US5532902A (en) * | 1995-02-08 | 1996-07-02 | Richmond Technology, Inc. | Air ionizing device |
US5550703A (en) * | 1995-01-31 | 1996-08-27 | Richmond Technology, Inc. | Particle free ionization bar |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3111605A (en) * | 1958-07-02 | 1963-11-19 | Bayer Ag | Gaseous-ion generator for rooms in which there is a danger of explosion |
-
1969
- 1969-06-12 US US832605A patent/US3619719A/en not_active Expired - Lifetime
- 1969-06-17 NL NL6909200A patent/NL6909200A/xx unknown
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3111605A (en) * | 1958-07-02 | 1963-11-19 | Bayer Ag | Gaseous-ion generator for rooms in which there is a danger of explosion |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4271451A (en) * | 1976-07-20 | 1981-06-02 | Hercules Incorporated | Method and apparatus for controlling static charges |
US4194232A (en) * | 1978-03-31 | 1980-03-18 | Cumming James M | Ion treatment of photographic film |
US4213167A (en) * | 1978-03-31 | 1980-07-15 | Cumming James M | Planar gas and ion distribution |
US4725732A (en) * | 1986-07-02 | 1988-02-16 | Xerox Corporation | Pin corotron and scorotron assembly |
US4725731A (en) * | 1986-07-02 | 1988-02-16 | Xerox Corporation | Photoreceptor deletion control by utilization of corona wind |
US5125936A (en) * | 1988-06-03 | 1992-06-30 | Boliden Contech Ab | Emission electrode |
US5121286A (en) * | 1989-05-04 | 1992-06-09 | Collins Nelson H | Air ionizing cell |
US5307234A (en) * | 1990-05-26 | 1994-04-26 | Haug Gmbh & Co. Kg | Corona discharger with counter electrode of wire coated by conductive plastic |
US5423216A (en) * | 1992-12-24 | 1995-06-13 | Shin-Etsu Chemical Co., Ltd. | Apparatus for automatically determining bulk specific gravity of powdery product |
US5550703A (en) * | 1995-01-31 | 1996-08-27 | Richmond Technology, Inc. | Particle free ionization bar |
US5532902A (en) * | 1995-02-08 | 1996-07-02 | Richmond Technology, Inc. | Air ionizing device |
Also Published As
Publication number | Publication date |
---|---|
DE1930465B2 (en) | 1972-11-23 |
DE1930465A1 (en) | 1970-08-27 |
NL6909200A (en) | 1969-12-19 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3619719A (en) | Static eliminators | |
US3156847A (en) | Ionizing air gun | |
US2333213A (en) | Static eliminator | |
NO167246B (en) | Ion generator. | |
ES2109425T3 (en) | LIGHTING SET AND LOW PRESSURE DISCHARGE LAMP WITHOUT ELECTRODE SUITABLE FOR USE IN SUCH SET. | |
KR890001147A (en) | Electrodeless low voltage discharge lamp | |
US3256439A (en) | High voltage and high current pulse generator in combination with field emission type x-ray tube | |
GB1416439A (en) | Electron discharge device | |
US2928941A (en) | Forced air ion generator | |
US3111605A (en) | Gaseous-ion generator for rooms in which there is a danger of explosion | |
US8587202B2 (en) | High-voltage insulator arrangement and ion accelerator arrangement having such a high-voltage insulator arrangement | |
US5121286A (en) | Air ionizing cell | |
US1863702A (en) | Gaseous conduction method and apparatus | |
US2791720A (en) | Replaceable element tr tube | |
US5281174A (en) | Corona treater high voltage plug-in | |
US2802998A (en) | Explosion-proof connector for electric lamps | |
US3636407A (en) | Gas-discharge device with magnetic means for extinguishing the discharge | |
KR830006811A (en) | Lighting system | |
JPH1154059A (en) | Ion source | |
US4035683A (en) | High voltage electric switch with trigger electrodes integral with main discharge electrodes | |
RU2034657C1 (en) | Electric pulse crusher | |
US2119675A (en) | Sodium lamp | |
US2830231A (en) | Electric discharge devices | |
US4156266A (en) | Light free static neutralizer | |
US2929947A (en) | Lead-in for electric currents in gas discharge vessels |