CA1095114A - Oxide coated electrode for corna generator - Google Patents
Oxide coated electrode for corna generatorInfo
- Publication number
- CA1095114A CA1095114A CA149,613A CA149613A CA1095114A CA 1095114 A CA1095114 A CA 1095114A CA 149613 A CA149613 A CA 149613A CA 1095114 A CA1095114 A CA 1095114A
- Authority
- CA
- Canada
- Prior art keywords
- wire
- generator
- corona
- tungsten
- oxide coating
- 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
Links
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/02—Apparatus for electrographic processes using a charge pattern for laying down a uniform charge, e.g. for sensitising; Corona discharge devices
- G03G15/0291—Apparatus for electrographic processes using a charge pattern for laying down a uniform charge, e.g. for sensitising; Corona discharge devices corona discharge devices, e.g. wires, pointed electrodes, means for cleaning the corona discharge device
-
- 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
Abstract
CORONA GENERATOR
ABSTRACT OF THE DISCLOSURE
A tungsten wire corona having a stable coating thereon for providing the generator with an extremely long life and a stable output.
ABSTRACT OF THE DISCLOSURE
A tungsten wire corona having a stable coating thereon for providing the generator with an extremely long life and a stable output.
Description
5~
, This invention relates to an inexpensive corona generator capable of producing a stable uniform output and having the relatively long operating life.
More specifically, this invention relates to an electrical corona generator capabl~ of producing a highly efficient discharge thus is well suited to effectively charge a receiving surface such as a xerographic plate or the like. This novel generator includes a corona emitting wire constructed of a tungsten material and having a surface coating thereon serving to extend the normal life of the generator and to smooth the corona deposited upon the plate receiving surface.
- Many methods and devices have been disclosed in the prior art for producing a uniform electrostatic charge upon a photoconductive plate. One such charging device is disclosed by Vyverberg in U.S. patent 2,836,725, issued May 27, 1958, wherein an electrode in the form of a wire surrounded by an electrically grounded conductive shield -is placed adjacent to a grounded receiving surface and a high voltage source connected to the wire wherein a corona discharge is produced. A corona discharge is produced when the generator is placed in close proximity to the plate and applied to the generator of sufficient magnitude to cause a breakdown of the ions in the air within the separating gap. As a result, charged ions are formed around the cOrQna generator flow to the grounded plate surfacè and are deposi~ed thereon to raise the plate potential to a relatively high level.
In the art of xerography it has been found that consistent reproductive quality can only be maintained when ' .
~ - 2 -'~ , .
-:
a uniform and constant charge potential is applied to thephotoconductive plate. In many automa-tic machines of this type, a single wire generator, generally referred to as a "corotron" is employed~ Generally, the efficiency of the corotron is dependent on many factors including the gap distance between the wire and the plate surface, the nature of the generating wire material, the diameter of the wire and other physical features thereof and the amount of energy supplied to the corona emitter. Heretofore, most corotrons were constructed of platinum or some other precious metal because these materials displayed -the ability to deliver uniform constant charging over a long period of time. As a conse~uence, these prior art devices were relatively expensive to construct and replacement costs were also high.
In accordance with one aspect of this invention there is provided the process of producing a corona genera-tor having a long operating life and a stable output includ-ing providing a tungsten wire having a relatively uniform diameter, cleaning the surface of said wire to remove foreign material therefrom, and oxidizing the surface of said wire in air at a temperature above the operating temperature of the generator to form a relatively continu ous and stable coatîng thereon.
In accordance with another aspect of this inven-tion there is provided in apparatus of the type for charg-ing thè surface of a photoconductive plate including a corona generator wire and a source of electrical energy operatively connected thereto for providing sufficient electrical energy to said wire to produce a corona dis-charge~therefrom, the improvement comprising a tungsten ' ~ -3-. . .
: .
wire generator having a tungsten oxide coating thereon which is stable within the operating range of said ~enerator whereby a substantially uniform corona output is produced within the working range of ~aid generator, said generator being substantially-surrounded by a shield having an axially aligned opening therein through which corona discharge is directed towards said plate.
In accordance with another aspect of this inven-tion there is provided in apparatus of the type for charging the surface of a photoconductive plate including a corona generator wire and a source of electrical energy operatively connected thereto for providing sufficient electrical energy to said wire to produce a corona dis-charge therefrom the improvement comprising a tungsten wire generator having a tungsten oxide coating thereon which is stable within the operating range of said generator whereby a substantially uniform corona output is produced within the working range of said generator, said tungsten wire having a diameter of approximately between 0.003 and .0060 inches and an oxide coating thereon of between 1/2 and 3 1/2 microns.
- 3a -~s~
For a better understanding of the present invention reference is had to the ~ollowing cletailed descrip-tion of the invention to be read in connection with the accompanying drawing wherein the drawiny illustrates a perspective view of a corona generating apparatus having a corona emitting wire fabricated in accordance with the teachings of the present invention.
Referring in particular to the attached figure, there is illustrated a corona generating device containing a generator wire of the present invention for depositing an electrostatic charge on the surface of a moving photo-conductive recording material. Illustrated on the figure is a xerographic plate 10 made up of a photoconductive insulating material 11 placed upon a grounded conductive substrate 12 with the plate being arranged to move along a predetermined path of travel in the direction indicated.
The corona generating unit, generally referred to as 15, is positioned above the plate surface and is arranged to deposit an electrical charge thereon as the plate surface movas in the direction indicated. The corona unit includes a shield member 17 which substantially encloses one or more corona generator wires 19. The shield is preferably made up of an electrically conductive material that is placed at a ground potential. A slit 20 or opening is formed in the bottom of the shield opposite the moving photoconductive surface and provides a path by which a flow of ions discharged by the generator are directed towards and deposited upon the ~" ' .
; -.
- . -: -- . . .
5~
moving plate surface. For further details regardin~ the structure of this type of corona generating unit, reference is had to the disclosure contained within the aforetomentioned Vyverberg patent.
The corona generating wire is ~onnected by suitable means such as electrical connector 21 to a hiyh potential source 23. The corona wire utilized in the present embodi-ment is connected directly to the positive terminal of the power source whereby a positive ion discharge is placed on the plate surface. However, it should be clear that an opposite arrangement can be employed to obtain a negative discharge. Basically, the generator is constructed of a fine wire between 0.003 and 0.006 inches in diameter made of a high quality tungsten being 99.95 percent pure. The wire preferably has a strength of about 280,000 psi. minimum and be capable of being elongated 1.4 percent over a 10 inch length when tested by ASTM method F219 (1) utilizing a cross head speed of approximately 1 3/4 inches per minute.
Normally~ a pure tungsten wire generator of this
, This invention relates to an inexpensive corona generator capable of producing a stable uniform output and having the relatively long operating life.
More specifically, this invention relates to an electrical corona generator capabl~ of producing a highly efficient discharge thus is well suited to effectively charge a receiving surface such as a xerographic plate or the like. This novel generator includes a corona emitting wire constructed of a tungsten material and having a surface coating thereon serving to extend the normal life of the generator and to smooth the corona deposited upon the plate receiving surface.
- Many methods and devices have been disclosed in the prior art for producing a uniform electrostatic charge upon a photoconductive plate. One such charging device is disclosed by Vyverberg in U.S. patent 2,836,725, issued May 27, 1958, wherein an electrode in the form of a wire surrounded by an electrically grounded conductive shield -is placed adjacent to a grounded receiving surface and a high voltage source connected to the wire wherein a corona discharge is produced. A corona discharge is produced when the generator is placed in close proximity to the plate and applied to the generator of sufficient magnitude to cause a breakdown of the ions in the air within the separating gap. As a result, charged ions are formed around the cOrQna generator flow to the grounded plate surfacè and are deposi~ed thereon to raise the plate potential to a relatively high level.
In the art of xerography it has been found that consistent reproductive quality can only be maintained when ' .
~ - 2 -'~ , .
-:
a uniform and constant charge potential is applied to thephotoconductive plate. In many automa-tic machines of this type, a single wire generator, generally referred to as a "corotron" is employed~ Generally, the efficiency of the corotron is dependent on many factors including the gap distance between the wire and the plate surface, the nature of the generating wire material, the diameter of the wire and other physical features thereof and the amount of energy supplied to the corona emitter. Heretofore, most corotrons were constructed of platinum or some other precious metal because these materials displayed -the ability to deliver uniform constant charging over a long period of time. As a conse~uence, these prior art devices were relatively expensive to construct and replacement costs were also high.
In accordance with one aspect of this invention there is provided the process of producing a corona genera-tor having a long operating life and a stable output includ-ing providing a tungsten wire having a relatively uniform diameter, cleaning the surface of said wire to remove foreign material therefrom, and oxidizing the surface of said wire in air at a temperature above the operating temperature of the generator to form a relatively continu ous and stable coatîng thereon.
In accordance with another aspect of this inven-tion there is provided in apparatus of the type for charg-ing thè surface of a photoconductive plate including a corona generator wire and a source of electrical energy operatively connected thereto for providing sufficient electrical energy to said wire to produce a corona dis-charge~therefrom, the improvement comprising a tungsten ' ~ -3-. . .
: .
wire generator having a tungsten oxide coating thereon which is stable within the operating range of said ~enerator whereby a substantially uniform corona output is produced within the working range of ~aid generator, said generator being substantially-surrounded by a shield having an axially aligned opening therein through which corona discharge is directed towards said plate.
In accordance with another aspect of this inven-tion there is provided in apparatus of the type for charging the surface of a photoconductive plate including a corona generator wire and a source of electrical energy operatively connected thereto for providing sufficient electrical energy to said wire to produce a corona dis-charge therefrom the improvement comprising a tungsten wire generator having a tungsten oxide coating thereon which is stable within the operating range of said generator whereby a substantially uniform corona output is produced within the working range of said generator, said tungsten wire having a diameter of approximately between 0.003 and .0060 inches and an oxide coating thereon of between 1/2 and 3 1/2 microns.
- 3a -~s~
For a better understanding of the present invention reference is had to the ~ollowing cletailed descrip-tion of the invention to be read in connection with the accompanying drawing wherein the drawiny illustrates a perspective view of a corona generating apparatus having a corona emitting wire fabricated in accordance with the teachings of the present invention.
Referring in particular to the attached figure, there is illustrated a corona generating device containing a generator wire of the present invention for depositing an electrostatic charge on the surface of a moving photo-conductive recording material. Illustrated on the figure is a xerographic plate 10 made up of a photoconductive insulating material 11 placed upon a grounded conductive substrate 12 with the plate being arranged to move along a predetermined path of travel in the direction indicated.
The corona generating unit, generally referred to as 15, is positioned above the plate surface and is arranged to deposit an electrical charge thereon as the plate surface movas in the direction indicated. The corona unit includes a shield member 17 which substantially encloses one or more corona generator wires 19. The shield is preferably made up of an electrically conductive material that is placed at a ground potential. A slit 20 or opening is formed in the bottom of the shield opposite the moving photoconductive surface and provides a path by which a flow of ions discharged by the generator are directed towards and deposited upon the ~" ' .
; -.
- . -: -- . . .
5~
moving plate surface. For further details regardin~ the structure of this type of corona generating unit, reference is had to the disclosure contained within the aforetomentioned Vyverberg patent.
The corona generating wire is ~onnected by suitable means such as electrical connector 21 to a hiyh potential source 23. The corona wire utilized in the present embodi-ment is connected directly to the positive terminal of the power source whereby a positive ion discharge is placed on the plate surface. However, it should be clear that an opposite arrangement can be employed to obtain a negative discharge. Basically, the generator is constructed of a fine wire between 0.003 and 0.006 inches in diameter made of a high quality tungsten being 99.95 percent pure. The wire preferably has a strength of about 280,000 psi. minimum and be capable of being elongated 1.4 percent over a 10 inch length when tested by ASTM method F219 (1) utilizing a cross head speed of approximately 1 3/4 inches per minute.
Normally~ a pure tungsten wire generator of this
2~ nature will initially exhibit extremely good corona generating properties. However, after a very short operating period, the uniformity of output, i.e. the distribution and amount of corona generated by the wire, becomes erratic and the generator exhibits signs of early electrical breakdown.
The reason for this short operating life is thought to be caused by loose randomly dispersed tungsten oxides which form on the wixe surface at the relatively low operating temperatures. These low temperature oxides are found to be metastable and correspondingly, cause an unstable ~'ischarge to be produced by the generator. Furthermore, the mechanical properties of these low temperature oxides are such that the oxides invariably spall from the wire in an un-controlled manner further aggravating the problems involved.
In the present invention, all the shortcomings previously associated with a tungsten wire corona generator have been overcome to provide a generator which is inexpen-sive to produce and which has an extremely long operating life and the capability of delivering an extremely uniform stable output over its entire operating life. To produce this truly novel result, the generator wire is specially treated to form an extremely smooth, uniform and tough coating thereon which will remain relatively stable throughout the operating life of the generator.
To produce this generator, a substantially pure tungsten wire having the beforementioned properties is chemically cleaned to remove foreign matter and grease from the surface of the wire and the wire stress relieved. Any suitable process commonly known and used in the art can be herein employed. The surface of the wire is oxidized in air at a temperature above the operat-ing temperature of the generator to form a relatively continuous and stable coating thereon. For example, the wire may be placed within an electrical oven and the oven heated to a temperature in excess of 600C in air to achieve the aforementioned objective.
A wire having a diameter of approximately 0.0035 inches, when heat treated in this manner for approximately 10 minut~s, will be pro-vided with an oxlde coating which is between 1.5 and 3.5 microns thick. An analysis of this coating shows that it is made up of high temperature oxides including WO2, WO3 and W18O49 Generating wires produced in this manner have been found to have an extremely stable coating which serves to prevent ~5~
physical changes in the wire at the operating temperature and provides for an extremely stable output and long operating life. The high tempexature oxide coating thus formed is relatively tough and is capable of readily with-standing light scraping with a metallic instrument. Spallingof the coating occurs only when the generator wire is per-manently deformed or kinked. II1 fact, the wire can be bent about a 1/4 inch diameter rod without disturbing the coating in any manner.
In order to ascertain the capabilities of the generator of the present invention, a test fixture was constructed by which the output of the generator could be evaluated and compared to similar generators constructed of other materials. The fixture basically consisted of a rotatably mounted grounded xerographic plate in drum configuration having a corona wire support mounted adjacent thereto for supporting a wire generator transverse to the drum surface. The wire generator was arranged to be electrically coupled to a high power source of electrical energy with the wire being supported above the drum surface at a distance whereby the corotron drew approximately 325 micro amps of current while charging-the plate surface to a potential of approximately ~00 volts. A thin brass strip was helically wound about the drum so that the strip continually monitored the bare plate current flow between the generator wire and the plate as the drum rotated under the generator. The brass strip was electrically brought out to a recording device by means of a slip ring and the recorde~r arranged to record data at approximately 25 mm/sec. Un~er these operating conditions, a bare plate ~s~
current of approximately 50 micro amps was initially recorded a~d the amplitude of the current deviation from this initial current reading was graphically registered.
A heat treated tungsten wire was placed within the test apparatus and continua:Lly operated for a period of approximately 250 hours. Periodic traces of the bare plate current reveal that the OlltpUt oE the heat treated generator remain relatively stable and unchanged over the test period. Subsequent to this test, a second corona generator of untreated tungsten wire similar in dimensions to that previously tested was placed within the fixture and an operating current placed thereon. After approxi mately 25 minutes of operation, the untreated tungsten generator began to produce a non-uniform and unstable output and thereafter the generator continued to electrically fail.
Next a comparison test of a heat treated tungsten generator and a platinum generator having similar physical properties was made. The wires were properties arranged in the fixture so as to produce the same bare plate current output at the dr~m surface. ~fter approximately 256 con-tinuous hours of operation, no differences in the performance of the platinum wire generator and that of the treated tungsten wire generator could be discerned.
While this invention has been described with reference to the structure herein disclosed, it is not confined to the details as set forth and this application is intended to cover any modifications or changes that may coMe within the! scope of the followin~ claims.
The reason for this short operating life is thought to be caused by loose randomly dispersed tungsten oxides which form on the wixe surface at the relatively low operating temperatures. These low temperature oxides are found to be metastable and correspondingly, cause an unstable ~'ischarge to be produced by the generator. Furthermore, the mechanical properties of these low temperature oxides are such that the oxides invariably spall from the wire in an un-controlled manner further aggravating the problems involved.
In the present invention, all the shortcomings previously associated with a tungsten wire corona generator have been overcome to provide a generator which is inexpen-sive to produce and which has an extremely long operating life and the capability of delivering an extremely uniform stable output over its entire operating life. To produce this truly novel result, the generator wire is specially treated to form an extremely smooth, uniform and tough coating thereon which will remain relatively stable throughout the operating life of the generator.
To produce this generator, a substantially pure tungsten wire having the beforementioned properties is chemically cleaned to remove foreign matter and grease from the surface of the wire and the wire stress relieved. Any suitable process commonly known and used in the art can be herein employed. The surface of the wire is oxidized in air at a temperature above the operat-ing temperature of the generator to form a relatively continuous and stable coating thereon. For example, the wire may be placed within an electrical oven and the oven heated to a temperature in excess of 600C in air to achieve the aforementioned objective.
A wire having a diameter of approximately 0.0035 inches, when heat treated in this manner for approximately 10 minut~s, will be pro-vided with an oxlde coating which is between 1.5 and 3.5 microns thick. An analysis of this coating shows that it is made up of high temperature oxides including WO2, WO3 and W18O49 Generating wires produced in this manner have been found to have an extremely stable coating which serves to prevent ~5~
physical changes in the wire at the operating temperature and provides for an extremely stable output and long operating life. The high tempexature oxide coating thus formed is relatively tough and is capable of readily with-standing light scraping with a metallic instrument. Spallingof the coating occurs only when the generator wire is per-manently deformed or kinked. II1 fact, the wire can be bent about a 1/4 inch diameter rod without disturbing the coating in any manner.
In order to ascertain the capabilities of the generator of the present invention, a test fixture was constructed by which the output of the generator could be evaluated and compared to similar generators constructed of other materials. The fixture basically consisted of a rotatably mounted grounded xerographic plate in drum configuration having a corona wire support mounted adjacent thereto for supporting a wire generator transverse to the drum surface. The wire generator was arranged to be electrically coupled to a high power source of electrical energy with the wire being supported above the drum surface at a distance whereby the corotron drew approximately 325 micro amps of current while charging-the plate surface to a potential of approximately ~00 volts. A thin brass strip was helically wound about the drum so that the strip continually monitored the bare plate current flow between the generator wire and the plate as the drum rotated under the generator. The brass strip was electrically brought out to a recording device by means of a slip ring and the recorde~r arranged to record data at approximately 25 mm/sec. Un~er these operating conditions, a bare plate ~s~
current of approximately 50 micro amps was initially recorded a~d the amplitude of the current deviation from this initial current reading was graphically registered.
A heat treated tungsten wire was placed within the test apparatus and continua:Lly operated for a period of approximately 250 hours. Periodic traces of the bare plate current reveal that the OlltpUt oE the heat treated generator remain relatively stable and unchanged over the test period. Subsequent to this test, a second corona generator of untreated tungsten wire similar in dimensions to that previously tested was placed within the fixture and an operating current placed thereon. After approxi mately 25 minutes of operation, the untreated tungsten generator began to produce a non-uniform and unstable output and thereafter the generator continued to electrically fail.
Next a comparison test of a heat treated tungsten generator and a platinum generator having similar physical properties was made. The wires were properties arranged in the fixture so as to produce the same bare plate current output at the dr~m surface. ~fter approximately 256 con-tinuous hours of operation, no differences in the performance of the platinum wire generator and that of the treated tungsten wire generator could be discerned.
While this invention has been described with reference to the structure herein disclosed, it is not confined to the details as set forth and this application is intended to cover any modifications or changes that may coMe within the! scope of the followin~ claims.
Claims (10)
1. The process of producing a corona generator having a long operating life and a stable output including providing a tungsten wire having a relatively uniform diameter, cleaning the surface of said wire to remove foreign material therefrom, and oxidizing the surface of said wire in air at a temperature above the operating temperature of the generator to form a relatively continuous and stable coating thereon.
2. The process of claim 1 wherein said wire has a diameter of between 0.003 and .0060 inches.
3. The process of claim 1 wherein said wire is oxidized in air at a temperature at or in excess of 600°C.
4. The process of claim 3 wherein said wire is heated for about 10 minutes to provide an oxide coating having a thickness of between 1/2 and 3 1/2 microns.
5. The process of claim 4 wherein said oxide coating includes the oxides of WO2, WO3 and W18O49.
6. The process of claim 5 wherein the oxide coating placed thereon is relatively smooth and unbroken over the surface of the wire.
7. In apparatus of the type for charging the surface of a photoconductive plate including a corona generator wire and a source of electrical energy opera-tively connected thereto for providing sufficient electrical energy to said wire to produce a corona discharge therefrom, the improvement comprising a tungsten wire generator having a tungsten oxide coating thereon which is stable within the operating range of said generator whereby a substantially uniform corona output is produced within the working range of said generator, said generator being substantially sur-rounded by a shield having an axially aligned opening therein through which corona discharge is directed towards said plate.
8. The apparatus of claim 7 wherein said shield is formed of a conductive material and is placed at a ground potential.
9. In apparatus of the type for charging the surface of a photoconductive plate including a corona generator wire and a source of electrical energy operatively connected thereto for providing sufficient electrical energy to said wire to produce a corona discharge therefrom, the improvement comprising a tungsten wire generator having a tungsten oxide coating thereon which is stable within the operating range of said generator whereby a substantially uniform corona output is produced within the working range of said generator, said tungsten wire having a diameter of approxi-mately between 0.003 and .0060 inches and an oxide coating thereon of between 1/2 and 3 1/2 microns.
10. The apparatus of claim 9 wherein said coating consists of the oxide including WO2, WO3 and W18O49.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US21154271A | 1971-12-23 | 1971-12-23 | |
| US211,542 | 1971-12-23 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1095114A true CA1095114A (en) | 1981-02-03 |
Family
ID=22787361
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA149,613A Expired CA1095114A (en) | 1971-12-23 | 1972-08-17 | Oxide coated electrode for corna generator |
Country Status (22)
| Country | Link |
|---|---|
| US (1) | US3764866A (en) |
| JP (1) | JPS5328099B2 (en) |
| AR (1) | AR198185A1 (en) |
| AT (1) | AT325420B (en) |
| AU (1) | AU467386B2 (en) |
| BE (1) | BE793227A (en) |
| BR (1) | BR7208756D0 (en) |
| CA (1) | CA1095114A (en) |
| CH (1) | CH553435A (en) |
| CS (1) | CS168018B2 (en) |
| DD (1) | DD103068A5 (en) |
| DE (1) | DE2245679C3 (en) |
| ES (1) | ES409976A1 (en) |
| FI (1) | FI57185C (en) |
| FR (1) | FR2165635A5 (en) |
| GB (1) | GB1402739A (en) |
| IL (1) | IL41096A (en) |
| IT (1) | IT972692B (en) |
| NL (1) | NL165341C (en) |
| SE (1) | SE380294B (en) |
| SU (1) | SU617026A3 (en) |
| ZA (1) | ZA729029B (en) |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3789278A (en) * | 1972-12-20 | 1974-01-29 | Ibm | Corona charging device |
| US3813549A (en) * | 1972-12-26 | 1974-05-28 | Ibm | Self-healing electrode for uniform negative corona |
| GB1554266A (en) * | 1975-07-14 | 1979-10-17 | Xerox Corp | Corona charging device |
| JPS5252641A (en) * | 1975-10-25 | 1977-04-27 | Mita Ind Co Ltd | Corona discharge device |
| US4110614A (en) * | 1976-12-17 | 1978-08-29 | Xerox Corporation | Corona device |
| US4910637A (en) * | 1978-10-23 | 1990-03-20 | Rinoud Hanna | Modifying the discharge breakdown |
| NL8101260A (en) * | 1981-03-16 | 1982-10-18 | Oce Nederland Bv | CORONA DEVICE. |
| JPS58182659A (en) * | 1982-04-20 | 1983-10-25 | Ricoh Co Ltd | Electrostatic charging method of electrophotographic device |
| JPS5952268A (en) * | 1982-09-20 | 1984-03-26 | Konishiroku Photo Ind Co Ltd | Transfer paper separating method |
| US5028779A (en) * | 1984-11-01 | 1991-07-02 | Xerox Corporation | Corona charging device |
| US4837658A (en) * | 1988-12-14 | 1989-06-06 | Xerox Corporation | Long life corona charging device |
| JP3619057B2 (en) * | 1999-05-28 | 2005-02-09 | キヤノン株式会社 | Charging device and image forming apparatus |
| CN104646566A (en) * | 2015-02-04 | 2015-05-27 | 安徽意义环保设备有限公司 | Corona wire bending frame |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE545664A (en) * | 1955-03-03 | |||
| US3537914A (en) * | 1968-01-19 | 1970-11-03 | Hewlett Packard Co | Passivation of thermal conductivity filaments |
-
0
- BE BE793227D patent/BE793227A/en not_active IP Right Cessation
-
1971
- 1971-12-23 US US00211542A patent/US3764866A/en not_active Expired - Lifetime
-
1972
- 1972-08-17 CA CA149,613A patent/CA1095114A/en not_active Expired
- 1972-09-14 AR AR244074A patent/AR198185A1/en active
- 1972-09-18 DE DE2245679A patent/DE2245679C3/en not_active Expired
- 1972-10-05 CH CH1453072A patent/CH553435A/en not_active IP Right Cessation
- 1972-12-11 CS CS8479A patent/CS168018B2/cs unknown
- 1972-12-12 BR BR8756/72A patent/BR7208756D0/en unknown
- 1972-12-15 NL NL7217159.A patent/NL165341C/en not_active IP Right Cessation
- 1972-12-15 IL IL41096A patent/IL41096A/en unknown
- 1972-12-18 GB GB5824872A patent/GB1402739A/en not_active Expired
- 1972-12-19 JP JP12758272A patent/JPS5328099B2/ja not_active Expired
- 1972-12-19 SE SE7216596A patent/SE380294B/en unknown
- 1972-12-20 FR FR7245484A patent/FR2165635A5/fr not_active Expired
- 1972-12-20 AT AT1088472A patent/AT325420B/en not_active IP Right Cessation
- 1972-12-20 AU AU50323/72A patent/AU467386B2/en not_active Expired
- 1972-12-20 IT IT33319/72A patent/IT972692B/en active
- 1972-12-20 FI FI3610/72A patent/FI57185C/en active
- 1972-12-21 ZA ZA729029A patent/ZA729029B/en unknown
- 1972-12-22 ES ES409976A patent/ES409976A1/en not_active Expired
- 1972-12-22 DD DD167839A patent/DD103068A5/xx unknown
- 1972-12-22 SU SU721865451A patent/SU617026A3/en active
Also Published As
| Publication number | Publication date |
|---|---|
| DD103068A5 (en) | 1974-01-05 |
| US3764866A (en) | 1973-10-09 |
| AU467386B2 (en) | 1974-06-20 |
| BR7208756D0 (en) | 1973-09-25 |
| FI57185B (en) | 1980-02-29 |
| IL41096A (en) | 1976-05-31 |
| DE2245679A1 (en) | 1973-07-05 |
| BE793227A (en) | 1973-06-22 |
| ES409976A1 (en) | 1976-06-16 |
| AR198185A1 (en) | 1974-06-07 |
| JPS5328099B2 (en) | 1978-08-12 |
| DE2245679C3 (en) | 1980-06-26 |
| FR2165635A5 (en) | 1973-08-03 |
| AU5032372A (en) | 1974-06-20 |
| NL165341C (en) | 1981-03-16 |
| SU617026A3 (en) | 1978-07-25 |
| GB1402739A (en) | 1975-08-13 |
| CH553435A (en) | 1974-08-30 |
| DE2245679B2 (en) | 1977-07-21 |
| NL7217159A (en) | 1973-06-26 |
| IT972692B (en) | 1974-05-31 |
| AT325420B (en) | 1975-10-27 |
| IL41096A0 (en) | 1973-03-30 |
| SE380294B (en) | 1975-11-03 |
| FI57185C (en) | 1980-06-10 |
| CS168018B2 (en) | 1976-05-28 |
| JPS4874231A (en) | 1973-10-06 |
| NL165341B (en) | 1980-10-15 |
| ZA729029B (en) | 1973-09-26 |
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