EP0316010B1 - Image forming apparatus with air exhaustion - Google Patents

Image forming apparatus with air exhaustion Download PDF

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Publication number
EP0316010B1
EP0316010B1 EP19880118847 EP88118847A EP0316010B1 EP 0316010 B1 EP0316010 B1 EP 0316010B1 EP 19880118847 EP19880118847 EP 19880118847 EP 88118847 A EP88118847 A EP 88118847A EP 0316010 B1 EP0316010 B1 EP 0316010B1
Authority
EP
European Patent Office
Prior art keywords
discharging
temperature
image forming
image
fixing
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
EP19880118847
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0316010A2 (en
EP0316010A3 (en
Inventor
Hiroaki Tsuchiya
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.)
Canon Inc
Original Assignee
Canon Inc
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 Canon Inc filed Critical Canon Inc
Publication of EP0316010A2 publication Critical patent/EP0316010A2/en
Publication of EP0316010A3 publication Critical patent/EP0316010A3/en
Application granted granted Critical
Publication of EP0316010B1 publication Critical patent/EP0316010B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • G03G15/0258—Apparatus for electrographic processes using a charge pattern for laying down a uniform charge, e.g. for sensitising; Corona discharge devices provided with means for the maintenance of the charging apparatus, e.g. cleaning devices, ozone removing devices G03G15/0225, G03G15/0291 takes precedence
    • 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
    • G03G15/20—Apparatus for electrographic processes using a charge pattern for fixing, e.g. by using heat
    • G03G15/2003—Apparatus for electrographic processes using a charge pattern for fixing, e.g. by using heat using heat
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G21/00—Arrangements not provided for by groups G03G13/00 - G03G19/00, e.g. cleaning, elimination of residual charge
    • G03G21/20—Humidity or temperature control also ozone evacuation; Internal apparatus environment control
    • G03G21/206—Conducting air through the machine, e.g. for cooling, filtering, removing gases like ozone

Definitions

  • the present invention relates to an image forming apparatus such as an electrophotographic copying apparatus provided with discharging means and heat fixing means, more particularly to an image forming apparatus provided with an air discharging function for discharging the air in the apparatus.
  • corona discharging devices having a corona wire to which a high voltage such as several KV is applied to effect corona discharge.
  • the types of corona discharging devices include generally a corotron type and scorotron type.
  • the corotron type discharger includes a shielding plate made of conductive material and a discharge wire enclosed therewith and made of a conductive fine wire having a diameter such as 50 - 100 microns, wherein a high voltage is applied to the discharging wire to produce corona discharge by which a member is charged or discharged by the ions electrolytically dissociated by the corona discharge.
  • the scorotron type discharger includes, in addition to the elements of the corotron type discharger grid, wires between the discharging wire and the member to be charged or discharged.
  • corona discharging wire is contaminated due to the dust collecting effects inherent to the discharge.
  • the contamination deteriorates the discharging properties with the result of non-uniform charging and discharging properties, or it produces abnormal discharging with the possible result of damage to the member to be charged or discharged. Since the service life of the corona discharging device is significantly dependent on the contamination of the corona discharging wire, various considerations have been made for the measure against the contamination.
  • the corona discharging device is accommodated in a hermetically sealed casing shield.
  • the discharge efficiency decreases to deteriorate the discharging properties.
  • Another consideration is supply of air into the discharger. It is a premise in this case that the foreign matter is removed beforehand using a dust filter, an electrostatic filter or the like. This method is efficient in that the discharge efficiency can be maintained high and in that the air flow in the discharger is one way. For those reasons, it has been widely used in various types of machines. However, there is a limit in removing the foreign matter by the filter or filters, because the foreign matter includes a developer, paper dust produced from the recording sheets, smoke of cigarettes, vapor of silicone oil used in the image fixing apparatus and silicone gas produced from the silicone rubber material used in the apparatus.
  • a means is considered to prevent deterioration of the charging properties, while permitting some contamination of the discharging wire.
  • discharging current is increased. By doing so, the clearance between the discharging wire and the photosensitive member can be increased, so that the non-uniformity can be decreased.
  • Another method of this type is to increase the density of the grid or employ a grid in the form of a mesh to supply a larger corona current to the grid to decrease the non-uniformity.
  • Another method proposed is to apply an alternating voltage to the discharging wire or the shielding plate to decrease the non-uniformity.
  • the problem of larger voltage source for the high voltage is also involved.
  • the increase of the current results in increased dust collecting effect, which worsens the contamination of the discharging wire and the shielding plate.
  • the application of the alternating voltage makes the structure of the apparatus more complicated.
  • a heat removing fan is disposed adjacent the image fixing apparatus, for example, which is actuated or deactuated in synchronism with the on and off of the power source.
  • the fan is deenergized even if the image fixing apparatus is in a high temperature state. If the temperature in the apparatus is low, the air is not discharged even if the image fixing device is being heated.
  • the image fixing device is of a heating roller type wherein silicone oil is applied to the roller or rollers used thereon, or when the roller has a silicone rubber layer
  • the discharging wire is contaminated strongly. It is considered that this is because the silicon vapor from the silicone rubber or the silicone oil is deposited on the discharging wire and is oxidized by the corona discharge energy to produce SiO2. This is intense when the oil applied contains dimethylsiloxane. Therefore, the deposition of the silicone vapor to the discharging wire is not effectively prevented by the heat discharging fan.
  • the deposition of the silicone vapor onto the discharging wire is not prevented by a fan for discharging the corona products.
  • Figure 1 is a sectional view of an image forming apparatus according to an embodiment of the present invention.
  • Figure 2 is a top plan view of the apparatus of Figure 1.
  • Figure 3 is a block diagram illustrating a discharge fan driving mechanism.
  • Figures 4 - 8 are timing diagrams illustrating the operational timing of the discharging or exhausting fan.
  • FIG. 1 there is shown a copying machine according to an embodiment of the present invention in a cross-section.
  • Figure 2 is a top plan view illustrating flow of air in the apparatus of Figure 1.
  • the copying machine comprises a photosensitive drum 1, a primary charger 2 having a discharging wire and a shield, an original supporting platen 3, an illumination device 4, mirrors 5 and 6, a lens 7, a dust-proof glass, a developing device 9, a transfer charger 10, a separation charger 11, a conveying belt 12, a fixing device 13 and a cleaning device 14.
  • the photosensitive drum 1 is rotated in the direction indicated by an arrow 1, during which it is uniformly charged by the primary charger 2.
  • the original on the original supporting platen glass 3 is illuminated by an illuminating device 4, and an image thereof is formed on the photosensitive member 1 by way of the mirrors 5 and 6, the lens 7 and the dust-proof glass 8, so that an electrostatic latent image is formed on the photosensitive drum.
  • the latent image is visualized by the developing device 9 and the toner image produced by the development is transferred onto a recording sheet by a transfer charger 10.
  • the recording sheet is then separated from the separation charger 11 from the photosensitive drum 1 and is carried on the conveying belt 12 to the fixing device 13. By this, the toner image on the recording sheet is fixed.
  • the photosensitive drum 1 is cleaned by the cleaning device 14 and is used for the repeated step.
  • the image fixing device 13 includes an upper roller 15 contactable to the unfixed toner image and a lower roller 16 for backing up the upper roller 15.
  • the upper roller 15 includes a cylindrical metal (aluminum, for example) and a coating layer of fluorine resin such as PFA and PTFE.
  • the upper roller 15 contains a heater 17 therein.
  • the lower roller 16 is a back-up or pressing roller having a core metal and a silicone rubber layer.
  • a web cleaning 18 is employed, and is impregnated with silicone oil. It is movable in a direction indicated by an arrow and is press-contacted to the upper roller 15 by the web roller 19 so as to clean the surface of the upper roller 15 and to apply the silicone oil as a releasing agent on the surface of the upper roller 15.
  • the copying apparatus includes an image forming station equipped with corona discharging devices 2, 10 and 11, wherein the charging, exposure, developing and image transfer steps are sequentially carried out to form a developed image on the recording sheet, and with an image fixing station which receives the recording sheet having the developed image and which fixes the developed image.
  • the silicone oil used in the image fixing apparatus is heated to become vapor and reaches the discharging device, where it is deposited on the discharging wire and is changed to a silicone oxide by the corona discharging action thereof. Therefore, this causes non-uniform discharge and abnormal discharge.
  • This embodiment provides a solution to the problem.
  • an exhausting fan 27 for discharging the air in the apparatus is provided, in addition to a heat discharging fan 30 for preventing overheating of the image fixing station.
  • a duct 24 is disposed having an opening 25.
  • the duct is connected to the exhausting fan 27.
  • the exhausting fan 27 serves to discharge the vapor produced by the image fixing operation, particularly, the silicone oil vapor to the outside of the apparatus, thus preventing the vapors reaching the discharger.
  • a duct 28 is disposed having an opening 29 and is connected to another exhausting fan not shown.
  • partition walls 20 and 21 for isolating introduction and discharge of the air between the image forming station including the discharging portions around the photosensitive drum 1 and the image fixing station 13.
  • the partition walls 20 and 21 are connected to the side plates 22 and 23 of the apparatus.
  • the vapors produced in the image fixing station are further prevented from reaching the discharging portion.
  • the air between the partition walls 20 and 21 is discharged, and therefore, the vapors produced at the image fixing station and passing beyond the partition wall 21 are discharged to the outside, and therefore, the vapors do not reach the discharging portion.
  • FIG. 3 is a block diagram of a driving mechanism for the discharging fan.
  • the driving mechanism includes a temperature sensor 32 in the form of a thermistor or the like for detecting the temperature of the fixing roller, a measuring circuit 33, a temperature controlling circuit 34, a comparing circuit 35, a driving circuit 36 for the discharging fan 27 and a DC controller 37.
  • the temperature sensor 32 detects the surface temperature of the image fixing roller and transmits it to the measuring circuit 33.
  • the output from the measuring circuit 33 is inputted into the temperature control circuit 34, where the current supply to the heater 17 of the fixing roller is controlled.
  • the output of the measuring circuit 33 is supplied to the comparing circuit 35 where it compares the surface temperature of the fixing roller with a predetermined temperature, and a driving signal 36 for driving the discharging from 27 is produced.
  • the temperature control circuit 34 receives a signal indicative of the stand-by state from the DC controller 37.
  • Figure 4 shows operational timing in an apparatus according to a preferred embodiment wherein the exhausting fan output is controlled at two levels in accordance with the temperature level of the image fixing roller.
  • a reference ON1 designates rotation of the exhausting fan at two thirds of the maximum rotational speed thereof
  • reference ON2 designates rotation of the exhausting fan at the maximum rotational speed.
  • the image fixing heater 17 when the main switch of the apparatus is turned on, the image fixing heater 17 is energized.
  • the wattage of the heater is 800 W.
  • the surface temperature of the image fixing roller increases through T1 (70 °C, for example) and T2 (150 °C, for example) to T3 (185 °C, for example).
  • the heater 17 is kept energized until the temperature T3 is reached. After it is reached, the heater is on-off-controlled so that the temperature thereof is maintained at T3.
  • T1 70 °C
  • the exhausting fan is energized by the level ON1 so that it is rotated at the speed 2/3 the maximum rotational speed.
  • the exhausting fan is energized by the level ON2 so that the rotational speed becomes maximum, thus increasing the exhausting power. If the copying machine is in on-state, the discharging fan continues this state.
  • the surface temperature of the image fixing roller is controlled to be T4 (140 °C, for example) lower than the temperature T2. Since the surface temperature of the fixing roller is now lower than T2, the energy supply level to the exhausting fan becomes ON1. If, the copying operation is instructed, the discharging fan is operated at level ON2 depending on the temperature of the fixing heater. When the main switch is turned off, the surface temperature of the fixing roller decreases.
  • the discharging fan becomes operated to ON1 when the temperature is lower than T2, and is turned off when the temperature is not less than T1.
  • the temperatures T1 and T2 may be selected property in accordance with the structure, configuration and material of the fixing device. Also, the consideration is made to the characteristics of the vapors produced by the used silicone rubber roller and the silicone oil. Generally, when a low viscosity oil is used, it is preferable that the temperatures T1 and T2 are relatively lower.
  • the web is impregnated with silicone oil having a viscosity 10,000 CS at a normal temperature. The viscosity of the silicone oil decreases with increase of the temperature, and the vapor pressure increases with the temperature.
  • the viscosity of the silicone oil can be adjusted by mixing with another oil having different viscosity. Those factors are to be considered together with other conditions of the apparatus, when the temperatures T1 and T2 are determined. It is preferable that the temperature T2 is slightly higher than the stand-by temperature when the apparatus has the stand-by temperature T4.
  • the exhausting fan in the conveying station is preferably operated in the similar manner as the fan 27.
  • the air flow in the apparatus is as shown in Figures 1 and 2, more particularly, two flows are established.
  • One is the flow from the inlet of the image fixing device to the opening of the duct, and the other is the flow from the dust proof filter 31 to the opening of the duct through the primary charger.
  • the second flow is effective to force to the duct opening the air flow produced by the corona wind by the primary charger along the upper part of the cleaner.
  • the partition walls 20 and 21 may be movable away from the conveying path so as to facilitate jam clearance operation when the recording sheet is jammed in the conveying path. It is not inevitable to provide both of upper and lower ducts, but sufficient effects can be provided only by the lower duct 28, although the deposition of the vapor on the discharging wire can be prevented assuredly by using both of the ducts.
  • FIG. 5 there is shown another embodiment of a sequential operation of an exhausting fan.
  • the exhausting fan is not operated at two levels, but the exhausting fan is always operated at level ON2 whenever the temperature of the fixing roller is at or above the temperature T1.
  • FIG. 6 another embodiment of the sequential operation is shown.
  • the operation of the exhausting fan is synchronized with the start of the energy supply to the fixing roller, and the operation of the exhausting fan is stopped a certain period ( ⁇ ) after termination of the energy supply to the fixing roller.
  • the exhausting fan starts with actuation of the main switch, but is stopped the certain period after the deactuation of the main switch.
  • the driving circuit 36 of Figure 3 receives on and off signals of the main switch and a signal from a timer circuit for measuring the time after the deactuation of the main switch. The time period ⁇ is determined so that the fixing roller is sufficient cooled.
  • the drive of the fan may be controlled in accordance with the energy supply to the heater in the manner described above. Since, however, the actual surface temperature of the roller is different from the predicted temperature due to the change in the ambience and the deterioration of the heater, it is preferable that the surface temperature of the roller is actually detected, and the drive of the fan is controlled on the basis of the detected temperature.
  • an auxiliary heater is provided adjacent the image fixing device in order to keep the temperature at a certain level during the main switch being off, although it is not shown in Figures 1 and 2.
  • FIG. 8 there is shown a sequential operation for operating the exhausting fan which is provided with an auxiliary heater, according to another embodiment of the present invention.
  • the auxiliary heater is energized during the period in which the main switch is off; and the auxiliary heater becomes off when the main switch becomes on.
  • the exhausting fan is operated at the level ON1 when the auxiliary heater is on, and is operated and the level ON2 when the apparatus is operated. Therefore, as long as the temperature is at or higher than the temperature T1 because of the provision of the auxiliary heater, the discharging fan is energized even during the main switch being off.
  • the silicone oil gases discharged from the inlet side of the image fixing apparatus are substantially sealed by the partition wall 20 and 21, and the gases are exhausted to the outside through the ducts 24 and 28 in accordance with the exhausting fan operating sequence. It is preferable that the upper part of the image fixing apparatus is provided with suitable heat discharging means.
  • the controlling sections 33, 34, 35, 36 and 37 are operated with DC of 5 V, and when the main switch is deactuated, the AC source only is deactuated, while the DC source is kept on, so that the DC power of 5 V is maintained even if the main switch is deactuated. Therefore, the drive control for the exhausting fan is possible after the main switch is actuated.
  • An image forming apparatus includes image forming device for forming a toner image on a recording material, the image forming device including electrical discharger, fixing device for fixing the toner image with heat, and air discharging device for discharging air between said fixing device and discharger in said apparatus, and controller for controlling the discharging device in accordance with a heated state of said fixing device.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Atmospheric Sciences (AREA)
  • Biodiversity & Conservation Biology (AREA)
  • Ecology (AREA)
  • Environmental & Geological Engineering (AREA)
  • Environmental Sciences (AREA)
  • Control Or Security For Electrophotography (AREA)
  • Fixing For Electrophotography (AREA)
EP19880118847 1987-11-12 1988-11-11 Image forming apparatus with air exhaustion Expired - Lifetime EP0316010B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP62286084A JP2578841B2 (ja) 1987-11-12 1987-11-12 画像形成装置
JP286084/87 1987-11-12

Publications (3)

Publication Number Publication Date
EP0316010A2 EP0316010A2 (en) 1989-05-17
EP0316010A3 EP0316010A3 (en) 1991-03-06
EP0316010B1 true EP0316010B1 (en) 1994-07-13

Family

ID=17699732

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19880118847 Expired - Lifetime EP0316010B1 (en) 1987-11-12 1988-11-11 Image forming apparatus with air exhaustion

Country Status (4)

Country Link
EP (1) EP0316010B1 (ja)
JP (1) JP2578841B2 (ja)
DE (1) DE3850633T2 (ja)
FR (1) FR2623305B1 (ja)

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5038170A (en) * 1989-03-30 1991-08-06 Kabushiki Kaisha Toshiba Cooling system for an image forming apparatus
US5307133A (en) * 1989-07-07 1994-04-26 Canon Kabushiki Kaisha Image fixing apparatus with means for preventing moisture dew on film
JP2714205B2 (ja) * 1990-02-17 1998-02-16 キヤノン株式会社 複写装置
IT1256874B (it) * 1992-02-17 1995-12-27 Olivetti Canon Ind Spa Dispositivo di ventilazione e raffreddamento per una fotocopiatrice.
FR2699698B1 (fr) * 1992-12-21 1995-02-24 Sagem Procédé et dispositif d'impression à transfert de charges et fixation par rouleau chauffant.
JPH07248654A (ja) * 1994-03-11 1995-09-26 Ricoh Co Ltd 画像形成装置の送風制御装置
US5819137A (en) * 1997-06-30 1998-10-06 Eastman Kodak Company Integrated environmental management for reproduction apparatus
JP3442003B2 (ja) 1999-07-30 2003-09-02 キヤノン株式会社 定着装置及び画像形成装置
JP2008139396A (ja) * 2006-11-30 2008-06-19 Konica Minolta Business Technologies Inc 画像形成装置
JP5538304B2 (ja) * 2011-05-25 2014-07-02 京セラドキュメントソリューションズ株式会社 画像形成装置
JP5983224B2 (ja) * 2012-09-14 2016-08-31 コニカミノルタ株式会社 画像形成装置
JP2015135370A (ja) 2014-01-16 2015-07-27 ブラザー工業株式会社 画像形成装置
JP6161572B2 (ja) * 2014-05-26 2017-07-12 京セラドキュメントソリューションズ株式会社 定着装置および画像形成装置
JP6197807B2 (ja) * 2015-02-24 2017-09-20 コニカミノルタ株式会社 画像形成装置
JP6635070B2 (ja) * 2017-02-21 2020-01-22 京セラドキュメントソリューションズ株式会社 定着装置及び画像形成装置
JP2019082577A (ja) * 2017-10-31 2019-05-30 富士ゼロックス株式会社 画像形成装置

Family Cites Families (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5225152Y2 (ja) * 1973-05-18 1977-06-08
US4178092A (en) * 1974-11-30 1979-12-11 Minolta Camera Kabushiki Kaisha Electrophotographic copying apparatus with gas evacuating means
CA1085446A (en) * 1974-11-30 1980-09-09 Shunji Yamamoto Electrophotographic copying apparatus
DE2653486A1 (de) * 1976-11-25 1978-06-01 Reinhold H Dr Epping Verfahren und vorrichtung zur fixierung elektrophotografisch erzeugter bilder auf einer unterlage
JPS5614248A (en) * 1979-07-16 1981-02-12 Canon Inc Image forming apparatus
JPS56146155A (en) * 1980-04-15 1981-11-13 Mita Ind Co Ltd Electrostatic copying machine
JPS58102968A (ja) * 1981-12-16 1983-06-18 Fuji Xerox Co Ltd 電子複写機の定着装置
JPS5824173A (ja) * 1982-07-13 1983-02-14 Toshiba Corp 電子複写装置
JPS5949571A (ja) * 1982-09-14 1984-03-22 Canon Inc 電子写真装置
JPS59114579U (ja) * 1983-01-24 1984-08-02 ミノルタ株式会社 複写機
JPS59154123A (ja) * 1983-02-22 1984-09-03 Sharp Corp 複写機のオゾン除去装置
JPS6037579A (ja) * 1983-08-11 1985-02-26 Toshiba Corp 画像形成装置
JPS61155U (ja) * 1984-06-07 1986-01-06 三洋電機株式会社 定着器付き機器の放熱装置
JPS6123168A (ja) * 1984-07-12 1986-01-31 Sharp Corp 複写装置
JPS61193173A (ja) * 1985-02-20 1986-08-27 Konishiroku Photo Ind Co Ltd 冷却部を有する記録装置
JPS6243664A (ja) * 1985-08-21 1987-02-25 Canon Inc 画像形成装置
US4693588A (en) * 1986-04-09 1987-09-15 Xerox Corporation Thermal air curtain for a copying/printing machine

Also Published As

Publication number Publication date
DE3850633D1 (de) 1994-08-18
EP0316010A2 (en) 1989-05-17
FR2623305A1 (fr) 1989-05-19
JP2578841B2 (ja) 1997-02-05
FR2623305B1 (fr) 1994-04-08
JPH01128073A (ja) 1989-05-19
EP0316010A3 (en) 1991-03-06
DE3850633T2 (de) 1994-11-10

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