JP2012053333A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus, in which charging unevenness on an image carrier is prevented by disposing a metal wire for charging separately from a charger for charging the image carrier, in a VOC (volatile organic compound) vapor, and VOC vapor is efficiently deposited on the metal wire and captured, based on special findings by the inventor.SOLUTION: The image forming apparatus includes at least transfer means depositing an unfixed toner image on the surface of a transfer member, fixing means heating and fixing the toner image transferred by the transfer means to the transfer member, an exhaust duct exhausting air near the fixing means from near the fixing device, and charging means disposed in the exhaust duct. The image forming apparatus also includes deposit cleaning means disposed in the exhaust duct for cleaning a substance depositing on the charging means while leaving a part of the substance.

Description

  The present invention attaches an unfixed toner image to the surface of a transfer member, heat-fixes the transferred toner image to the transfer member, and further releases volatile organic compounds generated during heat-fixing to the outside of the image forming apparatus. The present invention relates to an image forming apparatus provided with means capable of preventing leakage as much as possible.

Conventionally, when operating an image forming apparatus, it is known that various volatile organic compounds (VOC) are generated from the inside of the apparatus and discharged outside the apparatus. In particular, the fixing device uses a heating roller and a pressure roller using silicon rubber for fixing a toner image, and since these are high temperature, a large amount of volatile organic compound (VOC) containing siloxane gas is generated. Are known. Siloxane gas tends to adhere to surrounding members when the temperature is low, and if the surface of an electric circuit or relay contact is contaminated by siloxane gas, serious problems such as contact failure may occur. Further, it may adhere to optical elements in the image forming apparatus and affect the performance.
Therefore, it is necessary to devise a method for recovering siloxane generated in the fixing device. For example, in Patent Document 1, one end of an air duct connected to a fixing device is brought close to a charging wire for charging the surface of an image carrier, and siloxane is collected by a charging wire by a dust collection effect when a high voltage is applied. It is described.

JP, 2008-180805, A The charging wire used for such a publicly known image forming device is known to produce a dust collection effect when a high voltage is applied. The known method seems to be an excellent method in that the increase in cost can be suppressed.

However, in the dust collection method described in Patent Document 1, since the charging wire for charging the image carrier is used, there is a problem that uneven charging of the image carrier occurs even if it is temporary. is there.
According to the study by the present inventors, when a volatile organic compound (VOC) containing a siloxane gas is captured by a charging means such as a metal wire, the amount of volatile organic compound (VOC) captured depends on the surface state of the wire. It turns out that it fluctuates greatly. In particular, it was found that when an appropriate amount of VOC condensed on the surface of the wire is adhered, more VOC is captured than when there is no adhesion. It was also found that a larger amount of VOC can be captured when silicon oil is adhered to the metal wire than when there is no adhesion.
Accordingly, the present invention has been made to solve the above-described problems in the prior art, and by providing a metal wire for charging in the exhaust duct separately from the wire for charging to the image carrier, the image carrier is provided. An object of the present invention is to provide an image forming apparatus capable of eliminating the occurrence of uneven charging of the body and efficiently attaching VOC to a metal wire and capturing it based on special knowledge of the inventors.

In order to achieve the above object, an image forming apparatus according to the present invention includes:
At least transfer means for attaching an unfixed toner image to the surface of the transfer member, fixing means for heating and fixing the toner image transferred by the transfer means to the transfer member, and air in the vicinity of the fixing means from the vicinity of the fixing device An exhaust duct for exhausting;
Charging means provided in the exhaust duct;
An image forming apparatus comprising:
The image forming apparatus includes an adhering matter cleaning unit that is provided in the exhaust duct and cleans a part of the adhering matter adhering to the charging unit.
According to the knowledge obtained from the experiments by the present inventors, the charging means provided in the exhaust duct as described above has a function of fixing a volatile organic compound (VOC) containing a siloxane gas passing through the exhaust duct. However, such a function is more effective than the cleaning of all the deposits adhering to the charging means as described above. The efficiency of VOC recovery is improved at the shaving edge that is the boundary of. Accordingly, by providing the deposit cleaning means for cleaning the deposit with some of the deposit as described above, immobilization of the deposit is remarkably made efficient.
An embodiment in which the adhering matter cleaning means comprises a wire gripping part that sandwiches the wire as the charging means and a gripping part transporting means for moving the wire gripping part along the wire is advantageous. As suggested.
The wire gripping portion can be formed of a synthetic resin, a metal, etc., or a brush that sandwiches the wire.
Further, the function of fixing the volatile organic compound (VOC) containing siloxane gas to the charging means is further improved by the silicon oil adhesion means for adhering silicon oil to the charging means.
As a representative example of the charging means, a metal wire is usually used.
The control means that applies a positive voltage to the charging means is effective in adsorbing the VOC or the like.
Further, in order to improve the dust removing action by the charging means, it is effective to provide a counter electrode facing the charging means. Therefore, as an advantageous embodiment, in the exhaust duct, with respect to the charging means, Opposite electrodes are provided.
Furthermore, it is impossible to completely remove the volatile organic compound (VOC) containing the siloxane gas in the exhaust duct by the charging means described above. Therefore, the volatile organic compound is adsorbed in the exhaust duct. It is desirable to provide adsorption means to adsorb volatile organic compounds that are not supplemented and partitioned by charging means.
The adsorbing means is provided either between the charging means and the exhaust duct discharge section or in the vicinity of the exhaust duct discharge section, so that as much volatile organic compounds that could not be captured by the fixing device can be obtained. Adsorption is desirable.
The exhaust duct generally leads the air in the vicinity of the fixing device to the outside of the image forming apparatus. However, if the volatile organic compound can be absorbed in the image forming apparatus, the exhaust duct is The air in the vicinity of the fixing device can be guided into the image forming apparatus.

  As described above, the image forming apparatus according to the present invention includes at least a transfer unit that attaches an unfixed toner image to the surface of the transfer member, and a fixing that heats and fixes the toner image transferred by the transfer unit to the transfer member. An image forming apparatus comprising: a charging means provided in the exhaust duct; and an exhaust duct for exhausting air in the vicinity of the fixing means from the vicinity of the fixing device, and a charging means provided in the exhaust duct. Since the image forming apparatus is provided with an adhering matter cleaning means for cleaning a part of the adhering matter adhering to the charging means, the image bearing member can be transferred to the image bearing member without using a charging wire for the image bearing member. Since a charging metal wire different from the charging wire is installed in the VOC vapor to remove the VOC gas in the exhaust duct, it may cause uneven charging of the vapor image carrier. Without, it can be further based on the special knowledge by the inventor, to provide an image forming apparatus capable of capturing attached efficiently metal wire.

4 is a chart showing data in an example of an image forming apparatus according to an embodiment of the present invention. FIG. 3 is a cross-sectional view showing a portion of an exhaust duct of the image forming apparatus according to the embodiment of the present invention. Sectional drawing of an example (for color development) of the conventional image forming apparatus. 1 is a conceptual diagram of a charging unit used in an image forming apparatus according to an embodiment of the present invention. 1 is a block diagram showing a control system of an image forming apparatus according to an embodiment of the present invention. Sectional drawing which shows structures, such as a cleaning member used for one Embodiment of this invention. The side view which shows the structure of the cleaning mechanism X used for one Embodiment of this invention. The side view which shows the structure of the cleaning mechanism X used for other embodiment of this invention. Sectional drawing which shows structures, such as a cleaning member used for one Embodiment of this invention. Sectional drawing which shows structures, such as a cleaning member used for one Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.

First, the overall configuration of the color image forming apparatus Y according to the embodiment of the present invention will be described using the cross-sectional view shown in FIG. 3 and the control block diagram shown in FIG.
In the following description, the color image forming apparatus Y is taken as an example, but the principle is the same even for a monochrome image forming apparatus, and the present invention is also applied to a monochrome image forming apparatus. . Here, the color image forming apparatus Y will be described, and the description of the monochrome image forming apparatus will be omitted.
The image forming apparatus Y is a printer that is an example of a tandem type image forming apparatus that uses toner of four colors of black (BK), magenta (M), yellow (Y), and cyan (C).
The image forming apparatus Y includes an image forming unit α1, which forms a toner image, and forms an image on a recording sheet, a paper feeding unit α2, which supplies the recording sheet to the image forming unit α1, and a recording sheet on which the image is formed. Is discharged.
Image information (print job) received from a communication unit (not shown) from an external device such as a personal computer is transferred to black (BK), magenta (M), yellow (Y), cyan (image) by the image processing unit 12 shown in FIG. C), are converted into pixel gradations which are grayscale value information for each pixel for each of the four colors.

The image forming unit α1 uniformly forms the surface of each of the four photosensitive members 1 (1BK for black, 1M for magenta, 1Y for yellow, and 1C for cyan) carrying the images of the four colors. The charging device 23 (23BK, 23M, 23Y, 23C) to be charged, and the surface of each of the photoreceptors 1 charged in advance by the charging device 23 has an exposure amount corresponding to the pixel gradation determined by the image processing unit 12. An exposure source 2 (2BK, 2M, 2Y, 2C) for writing an electrostatic latent image on the photosensitive member 1 by irradiating (exposing) light to each pixel, and supplying toner to the electrostatic latent image Developing device 5 (5BK, 5M, 5Y, 5C) for developing as an image, intermediate transfer belt 7 for sequentially transferring the toner image formed on the surface of each of photoreceptor 1 and transferring the toner image to a recording paper, recording A conveying roller 8 for conveying the toner, a fixing device 9 for heating and fixing the toner image transferred onto the recording paper, and a static eliminating device 4 (4BK, 4M, 4Y) for removing the charge on the surface of the photoreceptor 1 after the toner image is transferred to the recording paper. , 4C) and the like.
In order to expose and scan the light beams of the respective colors emitted from the exposure source 2 (2BK, 2M, 2Y, 2C) onto the photoreceptor 1 (1BK, 1M, 1Y, 1C), a scanning device (not shown) is used. Used.

The photoconductor 1 is, for example, an a-Si photoconductor that is excellent in durability because of its high hardness and stable properties, and on the other hand, in addition to sensitivity unevenness, charging unevenness is likely to appear relatively remarkably.
The wire drive unit 21 shown in FIG. 5 controls the current that flows through the metal wire 23a of the charging devices 23 and 23 (see FIG. 2) provided in the exhaust duct D described later, and is a control program for the image forming apparatus Y. This can be realized by a part of the circuit or by providing another circuit.
The exposure source 2 shown in FIG. 5 is composed of an LED array in which a plurality of LEDs are arranged for each pixel in the axial direction (main scanning direction) of the photoreceptor 1 (1BK, 1M, 1Y, 1C). An example is shown. In addition, the exposure source 2 may be constituted by a laser scanning device or the like that scans laser light in the axial direction of the photoreceptor 1.
The developing device 5 includes a developing roller for supplying toner to the photosensitive member 1, and the developing device 5 has the potential (developing bias potential) applied to the developing roller and a potential gap between the surface of the photosensitive member 1 and the developing roller 5. The toner on the developing roller is attracted onto the surface of the photoreceptor 1 and the electrostatic latent image is visualized as a toner image.
The paper feeding unit α2 is roughly configured to include a paper feeding cassette 20, a paper feeding roller 6, and the like. The recording paper previously stored in the paper feed cassette 20 is conveyed to the image forming unit α1 when the paper feed roller 6 is driven to rotate.
The recording paper delivered from the paper feeding unit α2 is transferred by the transfer roller 8 and the toner image is transferred from the intermediate transfer belt 7. The recording sheet on which the toner image has been transferred is conveyed to the fixing device 9 (an example of a fixing unit), and is heated and fixed on the recording sheet by, for example, a heating roller, and then conveyed to the sheet discharge unit α3 and discharged. Is done.

The image processing unit 12, the data storage unit 13, the charging device 23, the exposure source 2, the developing device 5, the static eliminator 4, and the wire driving unit 21 are transmitted from the operation display unit 11 by the control unit 10 to which these are connected. Program control is performed based on input data or data such as various printing conditions stored in the data storage unit 13.
Conditions for driving the wire drive unit 21 include various data relating to the paper P (see FIG. 2) as an example of the transfer member, for example, the size of the paper P, the thickness of the paper P (usually input as basis weight Printing conditions such as the type of toner to be used, the printing rate, and the number of continuous prints.

The wire cleaning drive unit 27 drives a cleaning member (details will be described later) for removing a part of the solidified volatile organic compound (VOC) adhering to the metal wire 23a of the charging device 23. This is for regenerating the function of the wire 23a.
The wire cleaning driving unit 27 moves and controls the cleaning member along the metal wire 23a, and drives and controls the cleaning member for removing the volatile organic compound (VOC) attached to the metal wire 23a. At that time, the volatile organic compound (VOC) adhering to the metal wire 23a is not peeled off entirely, but the volatile organic compound (VOC) is peeled off by leaving a part of the adhering matter and cleaning it. It is important to make new volatile organic compounds (VOC) easily adhere to the surface.
Details will be described later.

On the other hand, details of the fixing device 9 and the exhaust duct D connected thereto are shown in FIG. In the image forming apparatus Y of FIG. 5, the fixing device 9 shows that the sheet is conveyed in the vertical direction (vertical conveyance). In FIG. 2, the sheet is conveyed in the horizontal direction. It is not an essential difference.
As shown in FIG. 2, the image forming apparatus Y according to this embodiment includes a fixing device 9 (an example of a fixing unit) including a heating roller 9d and a pressure roller 9a provided vertically below the heating roller 9d. The sheet P on which the toner image T has been transferred by the intermediate transfer belt 7 (an example of a transfer unit) proceeds while being gripped by the heating roller 9d and a pressure roller 9a provided vertically below the toner P. The image T is fixed on the paper P.
The upper space of the fixing device 9 including the heating roller 9d and the pressure roller 9a provided vertically below the heating roller 9d is covered by a lower opening Da opened so as to expand downward to the exhaust duct D. In the exhaust duct D connected to the lower opening Da, two charging devices 23 and 23 (an example of charging means) provided with a metal wire 23a are arranged. The metal wires 23a of these charging devices 23 are connected to the wire drive unit 21 described above, and the value of the inflow current applied to the metal wires 23a is controlled by the control unit 1 as described above.
In the exhaust duct D, the charging devices 23 are provided as described above. Further, a fan F is provided to force hot air rising from the fixing device 9 and siloxane gas contained in the hot air. It is desirable that the air is sucked into the exhaust duct D and further discharged outside the exhaust duct D.

The volatile organic compound (VOC) such as siloxane gas generated in the fixing device 9 is adsorbed and fixed by the metal wire 23a whose flow-in current is controlled according to the heat generation amount of the fixing device 9 as described above. However, not all siloxane gas is adsorbed. Accordingly, the siloxane gas or the like that has not been completely adsorbed by the charging devices 23 and 23 is adsorbed within the exhaust duct D or up to the outlet thereof, so that the exhaust containing as little siloxane gas as possible is removed. It is desirable to discharge indoors or outdoors.
As a means for this purpose, it is desirable to provide a suction means 25 such as a known filter between the charging device 23 and the discharge end of the exhaust duct D or in the vicinity of the discharge portion of the exhaust duct D.
In the example of FIG. 2, the suction means 25 is provided at the discharge end of the exhaust duct D.
Examples of these adsorbing means include known filters such as non-woven fabric, woven fabric, and screen.
The discharge end of the exhaust duct D can be opened toward the outside of the image forming apparatus Y. However, by opening the discharge end toward the inside of the image forming apparatus Y, the charging device 23 can be opened. , 23 or the adsorbing means 25, it is possible to prevent the siloxane gas or the like that has not been completely adsorbed from being discharged from the image forming apparatus Y.

  Further, in order to increase the charging efficiency of the charging device, it is desirable to install the counter electrode 23b so as to face the metal wire 23a and surround the metal wire 23a. A specific shape of the counter electrode 23b is shown in FIG.

  As described above, in this embodiment, volatile organic vapor such as siloxane gas is introduced into the exhaust duct D using the exhaust duct D and the fan F from the fixing device 9 where siloxane gas is easily generated. . Then, a metal wire 23b capable of applying a voltage is installed in the exhaust duct D. By applying a positive voltage to the metal wire 23a, siloxane gas or the like is attracted to the metal wire 23a and fixed.

As described above, according to the knowledge of the present inventor, the metal wire 23a adsorbs and fixes the volatile organic compound (VOC) generated in the fixing device 9 when a voltage is applied. Such a volatile organic compound (VOC) is adsorbed more by the metal wire 23a to which the solid matter of the volatile organic compound (VOC) adheres than the metal wire 23a to which nothing is fixed, It was found that if the wire 23a is completely covered with a volatile organic compound (VOC) solid, the efficiency of adsorption is significantly reduced.
Therefore, the present inventor cleans the metal wire 23a at a considerable cycle to remove the solid matter of the volatile organic compound (VOC) adhering to the periphery of the metal wire 23a. Focusing on the fact that such a special stripping method is most effective for solidifying a volatile organic compound (VOC), the deposit cleaning means for the metal wire 23a as shown in the following embodiment Was created.

〔Experimental device〕
FIG. 2 is a configuration diagram in the case where two metal wires 23a are installed in the exhaust duct D of the fixing device 9 of the image forming apparatus Y. The siloxane in the exhaust that has flowed through the exhaust duct D by the exhaust fan F is shown in FIG. When the gas flows around the metal wire 23a, it is suppressed from being deposited on the peripheral surface of the metal wire 23a as silica and being discharged outside the apparatus as a siloxane gas.
The specification of the metal wire 23a used in the experiment is as shown below, and the surface roughness Rmax is the maximum roughness (when measured according to the measurement method specified in JIS B0601: 2001 (ISO 4287: 1997)). μm).

Metal wire 23a: Tungsten wire with a diameter of 60 μm Rmax 0.9 μm
DC bias applied to the metal wire 23a: 6 kV
Distance between metal wire 23a / counter electrode 23b: 4 mm
Current flowing into the metal wire 23a 500 μA
The experiment was performed by comparing the following Examples 1 to 4 with Comparative Examples 1 and 2.

FIG. 6 shows a cleaning mechanism X of the metal wire 23a in the first embodiment, and FIG. 7 shows an overall view including a drive mechanism. As shown in FIGS. 6 and 7, the metal wire 23a is stretched between the support members 40a and 40b. A screw hole 46 of a cleaning member 44 is screwed into a screw 42 provided in parallel to the metal wire 23a at the upper part of the metal wire 23a, and the rotation direction of the cleaning member 44 is rotated by the rotation of the screw 42. In response to this, it moves in the left or right direction in FIG. The rotation start and rotation direction of the screw 42 are controlled by the wire cleaning drive unit (see FIG. 5) 27.
An opening / closing control member 48 parallel to the metal wire 23a is supported and fixed by the support members 40a and 40b below the metal wire 23a.
6A is a cross-sectional view taken along the line AA in FIG. 7, and FIG. 6B is a cross-sectional view taken along the line BB shown in FIG. 6A.
The cleaning member 44 is a long and thin plate-like member provided horizontally as shown in FIGS. 6 (a) and 6 (b). As shown in FIG. An enlarged portion 50 is formed. Both ends of the enlarged portion 50 form slopes 52.
As shown in FIG. 6A, the cleaning member 44 is a plate-like member in which a contact hole 54 with the metal wire 23a through which the metal wire 23a is inserted is formed. A notch 56 is formed. In addition, a vertical slit 58 is formed from the contact hole 54 to the notch 56, and the right and left leg portions 60, 60 of the notch portion 56 are subjected to a force that opens in the left-right direction in FIG. As indicated by arrows 62, 62 in (a), the leg portion 60 of the cleaning member 44 is opened (the slit 58 is opened), and a gap is formed between the contact hole 54 and the metal wire 23a inserted therein.
That is, the cleaning member 44 and the metal wire 23a inserted therein are always in contact with each other, and the cleaning member 44 moves along the metal wire 23a by the rotation of the screw 42, whereby the metal wire The silica fixed around 23a is peeled off by the cleaning member 44 and cleaned. In the present invention, the cleaning member 44 is an example of an adhering matter cleaning unit that is provided in the exhaust duct and performs cleaning while leaving a part of the adhering matter adhering to the charging unit.
Then, the cleaning member 44 moves along the metal wire 23a as indicated by the arrow 64 in FIG. 6B by the rotation of the screw 42, and the leg portion 60 reaches a position where it interferes with the enlarged portion 50 of the opening / closing control member 48. Then, the leg portions 60, 60 interfere with the enlarged portion 50, and the cleaning member 44 opens in the direction of the arrows 62, 62, and the contact between the metal wire 23a and the contact hole 54 is released. The cleaning process 23a is temporarily interrupted. The interruption is continued until the cleaning member 44 passes the enlarged portion 50, and when it passes, the cleaning process is continued again.
As described above, the screw 42 is an example of a gripper transport unit that moves the cleaning member 44 as an example of a wire gripper that sandwiches the wire as the charging unit along the metal wire 23a.
The cleaning member 44 may be configured by a brush or the like that holds the metal wire 23a.
Therefore, if the enlarged portion 50 of the opening / closing control member 48 is provided at various locations in the longitudinal direction of the metal wire 23a, the cleaning member 44 is moved from end to end of the metal wire 23a at a plurality of locations. , The part where the silica is not peeled off, that is, not cleaned can be made.
If the enlarged portion 50 is formed at both end portions of the metal wire 23a, the metal wire 23a is cleaned at the middle portion thereof, and is placed with the silica attached at both end portions thereof.
In FIG. 7, reference numerals 42a and 42b denote support parts for the screw 42, 46a denotes a boss part of the cleaning member 44, and 42b denotes a housing that accommodates a drive motor for the screw 42.
In this way, a shaved end portion of the silica formed by peeling off the silica is formed at various locations in the longitudinal direction of the metal wire 23a. Since a large amount of silica adheres to such a shaved end portion, in Example 1 in which the enlarged portion 50 is formed at a location corresponding to both end portions of the metal wire 23a as described above, Solidification of the volatile organic compound (VOC) vapor is promoted in the portion, and the outflow of the volatile organic compound (VOC) to the outside is more efficiently prevented.

  In Example 2 shown in FIG. 8, the enlarged portions 50 of the opening / closing control member 48 are formed at a plurality of locations in the longitudinal direction of the metal wire 23a. As a result, the scraped ends are respectively formed on the metal wires 23a corresponding to the plurality of locations where the enlarged portions 50 are formed. In this way, by performing intermittent and repeated cleaning at regular intervals, a lot of locations of the shaving edge where the siloxane gas is precipitated as silica are formed, and it is possible to have the precipitation part more efficiently. It becomes easier to deposit siloxane gas as silica than in Example 1.

  In the above embodiment, the contact hole 54 of the cleaning member 44 is widened by the interference between the opening / closing control member 48 and the leg portions 60, 60 of the cleaning member 44, so that the cleaning member 44 and the metal wire 23a However, this is merely an example. For example, a solenoid (not shown) that opens and closes the leg portions 60 and 60 of the cleaning member 44 is provided on the cleaning member 44, and the solenoid is connected to the solenoid. The opening / closing of the cleaning member 44 may be controlled by controlling on / off of the current. With such electrical control, the cleaning member 44 can be arbitrarily opened and closed, so that an excellent cleaning device can be provided in that the opening and closing of the cleaning member 44 can be controlled at any position or at any time. I can do it.

In the above-described embodiment, the scraped end is formed at the boundary portion by creating a portion that is not cleaned in the longitudinal direction of the metal wire 23a. Not only the above method but also various methods can be used.
For example, as shown in FIG. 9 corresponding to FIG. 6, the cleaning member 44a is moved in the longitudinal direction of the metal wire 23a in a state where the concave portion of the cleaning member 44a having a letter-shaped cross section is pressed against the upper surface of the metal wire 23a. It is also possible to peel off the silica-like solid of the siloxane gas at the contact portion between the cleaning member 44a and the metal wire 23a, and to form a shaved end portion continuously along the metal wire 23a. The numerical values shown in FIG. 1 are obtained by forming a shaved end portion continuously from end to end of the metal wire 23a.
Of course, it is also possible to control the generation of the shaving end by releasing the contact between the cleaning member 44a and the metal wire 23a using the open / close control member 48 or a solenoid.
In this way, by continuously forming the shaved end portion in the longitudinal direction of the metal wire 23a, it becomes easier to deposit siloxane gas as silica than in the first and second embodiments.

In FIG. 9, the cleaning member 44a is pressed against the upper portion of the metal wire 23a. In this case, as shown in FIG. 10, the cleaning member 44c having a cross-sectional shape is pressed against the lower surface of the metal wire 23a. .
By cleaning only half of the metal wire 23a, it is possible to have an appropriate precipitation portion as a whole, and it is easy to deposit siloxane gas as silica, and the same effect as in Example 3 is expected.

<Comparative Example 1>
In order to confirm the effects of the examples, two comparative examples were tried.
Comparative Example 1 is a case where the entire metal wire 23a is cleaned in Example 1.

<Comparative example 2>
Comparative Example 2 is a case where the metal wire 23a is not cleaned at all.

[Displacement measurement conditions]
The duct portion of the Kyocera Mita multifunction machine KM-C3232 is modified as shown in FIG. 2, and the metal wire 23a in which the silica is sufficiently deposited on the entire metal wire 23a is cleaned in accordance with the embodiments 1 to 4 described above. Installed in the exhaust duct D. However, Comparative Example 2 was not cleaned. A Kyocera Mita multifunction machine KM-C3232 was installed in a 5 m ³ chamber made of SUS and set to ventilate 15 m ³ / h. After ventilation for about 1 hour, printing was started for 10 minutes, and volatile substances generated from the inside of the machine were sampled at 100 ml / min with a Tenax tube. Thereafter, sampling was continuously performed for about 20 minutes after the printer was stopped. The sampled Tenax tube was desorbed with a heat desorption apparatus, measured with GC-MS, and the amount of siloxane gas generated was calculated. The calculation results are shown in FIG.
As shown in FIG. 1, in Comparative Example 1 in which the entire surface of the metal wire 23a was cleaned as compared with the case where the metal wire 23a was not cleaned at all as in Comparative Example 1 (detecting 108 μg / m ³ of siloxane gas in terms of toluene). As a result, 58 μg / m ³ of siloxane gas in a toluene equivalent concentration was detected, and the effect of cleaning the metal wire 23a was confirmed.
However, as in Example 1, when the shaved ends were formed at two locations, the entire end portion and the rear end portion of the metal wire 23a, a siloxane gas of 42 μg / m ^{3 in} terms of toluene was detected. As a result, the effect of forming the shaving edge became clear.
Further, when a plurality of shaving ends (5 in Example 2) are prepared as in Examples 2 to 4 or continuously, 24 μg / m ^{3 in} Example 2 in terms of toluene conversion. example 3 in 28μg / m ^3, as in example 4, 27 [mu] g / m ^3, a significant effect on the immobilization of the metal wire 23a of the siloxane gas was confirmed.
In addition, it is advantageous that the cleaning member 44 in the above-described embodiment and examples further includes a silicon oil adhering means provided in the exhaust duct D and adhering silicon oil to the metal wire 23a. .
By attaching such silicon oil, silicon adheres to the metal wire 23a, and the cleaning member 44 peels off a part thereof, thereby further improving the function of fixing the siloxane gas to the metal wire 23a. It is.

  The image forming apparatus according to the present invention can be applied to an image forming apparatus such as a copying machine or a facsimile, or an image forming apparatus as a complex machine having these functions and a scanner function.

Y ... Image forming apparatus D ... Exhaust duct Da ... Lower opening F ... Fan 1 (1BK, 1M, 1Y, 1C) ... Photoconductor 9 ... Fixing device 9a ... Pressure roller 9d ... Heating roller 23 ... Charging device 23a ... Metal Wire 23b ... Counter electrode 42 ... Screw 44 ... Cleaning member 46 ... Screw hole 48 ... Opening / closing control member 50 ... Enlarged portion 52 ... Slope 54 ... Contact hole 56 ... Notch portion 58 ... Slit 60 ... Leg portion

Claims (10)

At least transfer means for attaching an unfixed toner image to the surface of the transfer member, fixing means for heating and fixing the toner image transferred by the transfer means to the transfer member, and air in the vicinity of the fixing means from the vicinity of the fixing device An exhaust duct for exhausting;
Charging means provided in the exhaust duct;
An image forming apparatus comprising:
An image forming apparatus provided with an adhering matter cleaning unit provided in the exhaust duct and cleaning a part of the adhering matter adhering to the charging unit.   The said adhering matter cleaning means is comprised including the wire holding part which pinches | interposes the wire which is the said charging means, and the holding part conveyance means which moves this wire holding part along the said wire. Image forming apparatus.   The image forming apparatus according to claim 2, wherein the wire gripping portion is configured by a brush that sandwiches the wire.   The image forming apparatus according to claim 1, wherein the adhering matter cleaning unit is a unit that is pressed against one surface of the wire and peels off the adhering matter adhering to the one surface of the wire.   5. The image forming apparatus according to claim 1, further comprising a silicon oil adhering unit that is provided in the exhaust duct and adheres silicon oil to the charging unit.   The image forming apparatus according to claim 1, wherein the charging unit is a metal wire.   The image forming apparatus according to claim 1, wherein a counter electrode facing the charging unit is provided in the exhaust duct.   The image forming apparatus according to claim 1, wherein an adsorption unit that adsorbs a volatile organic compound is provided in the exhaust duct.   The image forming apparatus according to claim 1, wherein the suction unit is provided between the charging unit and a discharge part of the exhaust duct or in the vicinity of the discharge part of the exhaust duct. The image forming apparatus according to claim 1, wherein the exhaust duct is a duct that exhausts air in the vicinity of the fixing device toward or out of the image forming apparatus.

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