JPH035772A - Corona discharger - Google Patents

Abstract

PURPOSE:To prevent the uneven discharging, abnormal discharging, or the like by providing many ventilation holes on the overall surface of a shield member and coating the outside face with a sheet-shaped discharge product removing member and holding this member on the outside face of the shield member by a pressing member. CONSTITUTION:Many ventilation holes 23 are provided all over the surface of a shield member 13, and the outside face of this shield member 13 is coated with a sheet-shaped discharge product removing member 24, and this discharge product removing member 24 is held by the pressing member 28 on the outside face of the shield member 13. Consequently, ozone or the like due to corona discharge reaches the discharge product removing member 24 through ventilation holes 23 and is removed by adsorption and decomposition. Thus, the occurrence of the uneven discharging, abnormal discharging, or the like is prevented though the sheet-shaped discharge product removing member 24 is deformed by moisture absorption.

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to electrophotographic copying machines and other devices that copy or record images by forming an electrostatic latent image on a negatively charged photoreceptor. The present invention relates to a corona discharge device used in an image forming apparatus such as a printer.

[Prior art 1] Conventionally, in the above-mentioned electrophotographic copying machines, etc., selenium-based photosensitive materials have been mainly used as photoreceptors, and this photoreceptor is uniformly positively charged and has an electrostatic potential. An image is formed. However, recently, photoreceptors using a harmless organic photosensitive material (OPC), which can be disposed of by the user, have become mainstream.

At present, most of the organic photosensitive materials that are negatively charged are in practical use, and a photoreceptor using an organic photosensitive material is uniformly negatively charged by a corona discharge device, and then The image is exposed to light to form an electrostatic latent image.

However, when a corona discharge device is discharged negatively, oxygen in the air (0
2) is easily ionized, and the ionized oxygen further reacts with oxygen, nitrogen, etc., producing ozone (03) and nitrogen oxides (NOx).
etc. occur in large quantities.

The air containing ozone, etc. is exhausted outside the machine by an exhaust fan placed inside the electrophotographic copying machine, but ozone is a gas with a very strong odor, and the ozone concentration is o,
If a person is exposed to air containing about ippm for a long period of time, physiological effects such as shortness of breath, dizziness, headache, and nausea may be observed, which is harmful to the human body and is harmful to the human body. This is considered to be a problem with the equipment.

Not only that, but the ozone (0) generated from the corona discharge device
3) and nitrogen oxides (NOx) adhere to the surfaces of opposing photoreceptor drums, absorb moisture in high humidity environments, lower the surface resistance of the photoreceptor drums, and cause toner image fogging and image blurring. There was a problem in that it occurred. In addition, ozone has a strong chemical action and causes a chemical reaction with the photoreceptor, resulting in the problem that the original electrophotographic characteristics are lost over time.

In order to solve these problems, as a means to remove and reduce ozone etc. emitted from electrophotographic copying machines, for example, ozone-decomposing substances are filled in the openings that discharge air containing ozone or are moored with non-woven fabric. Methods have been adopted to use filters to decompose ozone and other substances or prevent them from being released, such as by providing filters with a larger contact area or by improving air flow.

However, in such a case, it is necessary to use a special filter or change the exhaust structure of the copying machine, etc., resulting in an increase in cost. Also,
There was also the problem that it was not possible to efficiently prevent ozone and the like generated by the corona discharge W1 device from directly adhering to the photoreceptor drum.

Therefore, as a means to efficiently decompose and remove ozone, etc. without increasing costs, ozone, etc. It has been proposed and implemented to disassemble and remove.

[Problems to be Solved by the Invention] However, the above prior art has the following problems. In other words, when activated carbon sheets are pasted on the inner and outer surfaces of the shield of a corona discharge device, the adhesive may peel off under high tMaI humidity, or the activated carbon sheet may absorb moisture and cause deformations such as warping or waving, causing the discharge wire and shield to peel off. There was a problem in that the distance between the activated carbon sheets attached to the inner surface of the battery varied, causing uneven discharge and abnormal discharge. Furthermore, if the activated carbon sheet becomes fluffy, spark discharge occurs between the activated carbon sheet and the discharge wire, and in some cases, the discharge wire may be cut.

Furthermore, since the activated carbon sheet has a limited lifespan in its ability to adsorb ozone and the like, if the activated carbon sheet's ability to adsorb ozone and the like decreases over its lifespan, the activated carbon sheet needs to be replaced. However, since the activated carbon sheet is bonded to the shield with an adhesive, it is difficult to replace only the activated carbon sheet, and the entire corona discharge device must be replaced, which is uneconomical. [Means for Solving Problem 111] Therefore, the present invention was made to solve the problems of the above-mentioned prior art, and its purpose is to provide a sheet-like discharge product such as an activated carbon sheet. Even if the removal member absorbs moisture and becomes deformed, it can prevent uneven discharge or abnormal discharge from occurring.Moreover, if the sheet-shaped discharge product removal member such as an activated carbon sheet reaches the end of its life, the discharge product can be removed. It is an object of the present invention to provide a corona discharge device in which only the product removal member can be easily replaced and the running cost of the device can be reduced.

That is, the present invention provides a corona discharge device comprising a discharge wire stretched between a pair of insulating members and a shield member disposed opposite to the discharge wire, in which a large number of ventilation holes are provided on the entire surface of the shield member. At the same time, the outer surface of the shield member is covered with a sheet-shaped discharge product removal member, and the sheet-shaped discharge product removal member is held on the outer surface side of the shield member by a pressing member. .

For example, small circular ventilation holes are drilled at the same intervals in the shield member, but the shape of the ventilation holes is not limited to this, and may be any shape such as a hexagonal shape or a rectangular shape. Of course.

In addition, as a sheet-shaped discharge product removal member, an activated carbon sheet is used, for example, but it is not limited to this, and other materials can be used as long as they can remove discharge products such as ozone and nitrogen oxides. Of course, you can also use something. Other sheet-shaped discharge product removal members may include, for example, sheets whose surfaces are plated or vapor-deposited with metals such as nickel, aluminum, copper, etc. that have the effect of decomposing ozone and nitrogen oxides. good.

Note that the term "removal of discharge products" as used herein is a concept that includes all methods by which discharge products can be removed by adsorbing, absorbing, decomposing, or the like.

Furthermore, the activated carbon sheet may support powdered metal or gold R oxide, if necessary. As this metal oxide, for example, manganese oxide is used.

However, other metals include Pt1Pd, A
Noble metals such as g, Ru, Rh, etc. can be used. In addition, as metal oxides other than manganese oxide, Ti
, VlCrlMnlFe.

Oxides of transition metals such as C01N+ and W can be used. Furthermore, in addition to these, zeolite, activated alumina, silica gel, etc. may be supported on the activated carbon sheet, or these may be used alone as necessary.

The holding member for holding down the sheet-shaped discharge product removal member may be made of, for example, a thin metal plate, but any other material may be used as long as it can hold the sheet-shaped discharge product removal member. But of course it's good.

[Function] In this invention, a large number of ventilation holes are provided on the entire surface of the shield member, and the outer surface of the shield member is covered with a sheet-shaped discharge product removal member. Since the holding member is used to hold the shield member on the outer surface side, ozone generated by corona discharge passes through the ventilation holes drilled in the shield member and is transferred to the sheet-shaped discharge products held on the outside of the shield member. The removal member is reached.

Then, ozone and the like are adsorbed and decomposed by this sheet-shaped discharge product removal member and removed. In addition, this sheet-shaped discharge product removal member is held on the outer surface side of the shield member by a holding member, so when the discharge product removal member reaches the end of its life, the holding member can be removed and the discharge products removed. Only the removed member is replaced with a new one.

[Example] The present invention will be explained below based on illustrated embodiments.

FIG. 7 shows an electrophotographic copying machine to which the corona discharge device according to the present invention can be applied. In the figure, reference numeral 1 denotes a photosensitive drum to which an image of a document placed on a platen glass (not shown) is exposed, and the photosensitive drum 1 is rotatable in the direction of the arrow by a driving means (not shown). The photosensitive drum 1 is made of, for example, an organic photosensitive material (OPC), and the surface of the photosensitive drum 1 made of this organic photosensitive material is as described below. Uniformly negatively charged and electrostatic WJl
lEI is formed.

The photosensitive drum 1 is uniformly charged to a predetermined negative voltage by a primary charger 2 prior to exposing the image of the original, and then the image of the original is exposed to form an electrostatic latent image. This electrostatic latent image is developed into a toner image by the developing device 3, and this toner image is transferred onto the transfer paper 5 by being charged by the transfer charger 4. The transfer paper 5 is supplied from the paper feed cassette 6 to the surface of the photoreceptor drum 1 at a predetermined timing. On the other hand, the transfer paper 5 to which the toner image has been transferred is
After being separated from the surface of the photoreceptor drum 1 by charging by the separation charger 7 , it is sent to the fixing device 9 by the conveyor belt 8 . The fixing device 9 fixes the toner image onto the transfer paper 5, and the transfer paper 5 is discharged onto an unillustrated discharge tray provided outside the machine. Furthermore, after the transfer process is completed, untransferred toner remaining on the surface of the photoreceptor drum 1 is
It is removed from the surface of the photoreceptor drum 1 by the cleaning device 10 . Furthermore, the photoreceptor drum 1 is exposed to light by the static elimination lamp 11 to remove residual charges, and is prepared for the next copying process.

The corona discharge device according to an embodiment of the present invention is used, for example, as the -number charger 2, but is not limited to this, and can be used as a transfer charger, a separation charger, or a pre-transfer charger. Of course, it may also be used as a static eliminator, etc.

FIG. 1 shows an embodiment of a corona discharge device according to the present invention. In the figure, 12 is a corona discharge device, and this corona discharge device 12 includes a shield member 1 formed in an elongated box shape from a metal plate made of stainless steel or the like.
It has 3. As shown in FIGS. 2 and 6, this shield member 13 is provided on both sides! 114.15 and ceiling wall 16
It is formed into a U-shaped cross section, and an opening 17 is provided on the lower side thereof. Further, the ceiling wall 16 of the shield member 13 is extended to both ends, and insulating blocks 18 and 19 are attached to the extensions 16a and 16b as described below.

At both ends of the shield member 13, extension portions 16a,
A pair of insulating blocks 18.19 are fixed to 16b by means such as screws, and both insulating blocks 18.1
A discharge wire 20 made of a thin tungsten wire or the like is stretched between the two. In the figure, 22 is a discharge wire 20
The terminal for applying high voltage to is shown.

Then, by applying a negative high voltage to the discharge wire 20 via the voltage application terminal 22 and connecting the shield member 13 to the ground, a corona discharge is generated from the discharge wire 20 toward the shield member 13. However, due to the ions released along with this corona discharge,
The surface of the photosensitive drum 1 is uniformly charged negatively.

At this time, discharge products such as ozone (03) and nitrogen oxides (NOx) are also released along with the corona discharge.

By the way, in this embodiment, a large number of ventilation holes are provided on the entire surface of the shield member, and the outer surface of the shield member is covered with a sheet-shaped discharge product removal member. It is configured to be held on the outer surface side of the shield member by a pressing member.

That is, the shield member 13, as shown in FIG.
There are small circular ventilation holes 23.23... on the entire surface.
A large number of holes are uniformly drilled with the same diameter and at the same intervals. As described above, by providing a large number of ventilation holes 23, 23, etc. on the entire surface of the shield member 13, discharge products generated by corona discharge as described above can be prevented from flowing through the ventilation holes 23, 23, .
..., and is adsorbed and removed by a discharge product removal member, which will be described later.

Further, by providing a large number of ventilation holes 23, 23, . . . on the entire surface of the shield member 13, the following effects can also be achieved. That is, it is known that as corona discharge progresses over time, discharge products adhere to the inner surface of the shield member 13, and the inner surface of the shield member 13 becomes partially insulated.

As a result, electric lines of force from the discharge wire 20 are selectively generated on both side walls 14 and 15 of the partially insulated shield member 13 and on the ceiling wall 16, so that electric lines of force are generated on the surface of the photoreceptor drum 1. Discharge distribution tends to become uneven. Furthermore, when using a constant current power source that is normally used as a power source for a corona discharge device, the current flowing through the discharge wire 20 also increases due to the influence of the above-mentioned aging, so it is necessary to use a constant current power source with a large capacity. , which results in high costs.

On the other hand, the ventilation holes 23, 23 and 23 in the shield member 13
When a large number of ... are drilled over the entire surface, the lines of electric force from the discharge wire 20 go toward the edges of the ventilation holes 23, 23, etc., so that the shielding member 13 becomes more stable over time than when the shield member 13 is flat. It becomes harder to get injured. Therefore, the shield member 13
Even if discharge products adhere to the inner surface of the shield member 13 and the inner surface of the shield member 13 is partially insulated, lines of electric force from the discharge wire 20 are generated toward the edges of the vent holes 23, 23, etc. Therefore, occurrence of uneven discharge, increase in discharge current, etc. can be prevented.

Further, the outer surface of the shield member 13 is coated with an activated carbon sheet 24 as a sheet-shaped discharge product removing member. The activated carbon sheet 24 is a paper material with finely granular activated carbon held on its surface. For example, an activated carbon sheet manufactured by Toyobo Co., Ltd., model number P-165N can be used as the activated carbon sheet 24. can.

As shown in FIG. 3, the activated carbon sheet 24 covers both side walls 14, 15 of the shield member 13 and all of the ceiling wall 16, including both side walls 25, 26 and the ceiling! ! 27
It is bent into a U-shaped cross section.

Further, the activated carbon sheet 24 is held on the outer surface of the shield member 13 by a pressing member 28. As shown in FIG. 4, this holding member 28 is made of a thin metal plate or synthetic resin plate having spring properties.
It is formed into an elongated rectangular parallelepiped frame shape corresponding to the shape of the shield member 13. Furthermore, in detail, the presser member 28
As shown in FIG. 1, the mounting attached to the outer periphery of the insulating block 18.
9 and 30 and a presser plate part 31 and 32 installed between the two parts.

As shown in FIG.
．． 34. Also,
The holding plate portions 31.32 are attached to both IIMs of the activated carbon sheet 24 at installation tS29.30! 25.26 A flat plate 35.36 is installed at the tip of the activated carbon sheet 24 at 29.30, and the ceiling is attached to both side walls 25.26 of the activated carbon sheet 24! 27, and the above-mentioned attachment is done by the arm piece 33. of the part 29.30.
34 and L-shaped plates 37 and 38 each having a box-shaped cross section.

As shown in FIG. 1, the pressing member 28 is configured to press the outside of the activated carbon sheet 24 while covering the outer periphery of the shield member 13 with the activated carbon sheet 24. At this time, since the presser member 28 is made of a material having spring properties, the presser member 28
When installing the L-shaped plates 37 and 38, as shown in FIG.
．． 32 is attached to the outer periphery of the insulating block 18, 19.

By doing this, the activated carbon sheet 24 coated on the outer periphery of the shield member 13 is covered with the outer periphery of the shield member 13 by the flat plate 35, 36 and the L-shaped plate 37, 38 of the pressing member 28, as shown in FIG. is maintained.

In the above configuration, in the corona discharge device according to this embodiment, discharge products such as ozone are removed in the following manner. That is, the corona discharge device 12 applies a negative high voltage to the discharge wire 20 through the terminal 22 while being installed in an electrophotographic copying machine or the like, thereby discharging the discharge wire 20 toward the shield member 13. Corona discharge occurs. At this time, as described above, discharge products such as ozone and nitrogen oxides are generated along with the corona discharge.

By the way, as shown in FIG. 2, the shield member 13 is provided with a large number of ventilation holes 23, 23... over its entire surface, so that the lines of electric force from the discharge wire 20 are as shown in FIG. As shown, it mainly occurs toward the edges of the ventilation holes 23, 23, . . . . Therefore, the ion wind generated along the electric lines of force is generated in the direction of passing through the ventilation holes 23, 23, . . . formed in the shield member 13.

Therefore, discharge products such as ozone generated by corona discharge by these ions are also carried to the ventilation holes 23, 23, etc. of the shield member 13, and most of the discharge products are transferred to the outer surface of the shield member 13'. It is adsorbed and decomposed by the retained activated carbon sheet 24 and removed. Therefore,
Discharge products such as ozone generated by the corona discharge of the corona discharge device M12 may adhere to the photoreceptor drum 1 and deteriorate the characteristics of the photoreceptor, or the discharge products may be emitted outside the copying machine and pose a hazard to humans. can be prevented from having a negative impact on

At this time, in a high humidity environment, the activated carbon sheet 24 may absorb moisture and deformation such as warping or waving may occur in the activated carbon sheet 24. However, the activated carbon sheet 24 is
Since it is held on the outer surface of the shield member 13 by the presser member 28, the shield member 13 has ventilation holes 23, 23, and 23.
Even if the activated carbon sheet 24 is perforated, the deformed activated carbon sheet 24 and its fluff will not protrude inside the shield member 13. Therefore, even if the activated carbon sheet 24 is deformed such as warping, abnormal discharge such as uneven discharge or spark discharge will not occur.

Further, the ability of the activated carbon sheet 24 to remove ozone, etc. has a limited lifespan, but since the activated carbon sheet 24 is only held by the presser member 28 on the outside of the shield member 13, the presser member 28 cannot be held by hand. It is possible to easily remove the activated carbon sheet 24 and replace it with a new one.

Therefore, unlike in the past, there is no need to replace the entire corona discharge device with a new one when the activated carbon sheet reaches the end of its life, so the running costs of copying machines and the like can be reduced.

In the above embodiment, the ventilation holes 23, 23, etc. formed in the shield member 13 are circular, but are not limited to this, and as shown in FIG. 9, they are hexagonal. Of course, the shape may be a rectangular shape as shown in FIG. 10.

FIG. 11 shows still another embodiment of the present invention, in which the same parts as in the previous embodiment are denoted by the same reference numerals. In this embodiment, a strong i
By generating a flow of air in a uniform manner, the discharge product removing member held on the outer surface of the shielding member can be used efficiently.

In other words, for electrophotographic copying machines, etc., ff! As shown in Figure 12, ozone generated inside the machine is discharged to the outside,
An exhaust fan 40 is provided to cool the inside of the machine u1. The exhaust fan 40 is disposed on the side wall of the fixing device 9, which normally generates a large amount of heat. Therefore, the exhaust fan 40 generates an air flow inside the copying machine as indicated by the arrow in FIG.

Therefore, when the corona discharge device 12 according to this embodiment is used as the primary charger 2 of a copying machine, the above-mentioned air flow generates an air flow as shown in FIG. 13 within the corona discharge device 12. Therefore, as described above, discharge products such as ozone generated by corona discharge are caused by the ionic wind to flow through the ventilation holes 23, 23, etc. of the shield member 13.
However, at the same time, under the influence of the air current, the first
As shown in FIG. 3, the shield member 13 is conveyed in a biased manner toward one side wall.

Therefore, the activated carbon sheets 2 on both side walls of the shield member 13
4, a difference in the adsorption amount of discharge products occurs, and the discharge device 11
The amount of discharge products adsorbed by the activated carbon sheet 24 on the leeward side of the activated carbon sheet 24 increases. Therefore, the life of only one side wall of the activated carbon sheet 24 is short, and the activated carbon sheet 24 must be replaced earlier than its original life.

Therefore, in this embodiment, as shown in FIG. 11, an opening 41 is provided in the ceiling wall of the shield member 13, and air is forced into the interior of the shield member 13 through the opening 41 by an auxiliary fan 42. , and as shown in FIG.
16 to generate a flow of air that flows out approximately uniformly. In the figure, 43 indicates a duct.

By doing this, the exhaust fan 4 can be installed inside the copying machine, etc.
Even when there is an air flow associated with the exhaust of 0.0, the air current flowing approximately equally toward both side walls 15 and 16 of the shield member 13 is generated inside the corona discharge device 12, as shown in FIG. Therefore, the activated carbon sheet 24 coated on the outer surface of the shield member 13 can be used efficiently, and the efficiency of removing ozone and the like is increased, and the life of the shield member 13 can be extended.

FIG. 14 and FIG. 15 show still another embodiment of the present invention, and the same parts as in the above embodiment are given the same reference numerals. In this embodiment, a corona discharge device emits light. By incorporating elements, the device is made smaller.

That is, in an electrophotographic copying machine, as shown in FIG. 16, the photosensitive drum may be charged by corona discharge and discharged by exposure at the same time. In this case, the corona discharge device 12 and the exposure device 50 are used together. However, as shown in FIG. 16, when the corona discharge device 112 and the exposure device 50 are arranged along the circumferential direction of the photoreceptor drum 1, a large space is required. As shown in FIG. 2, even when the corona discharge device 12 and the exposure device 50 are partially integrated, the device is not sufficiently miniaturized.

Therefore, in this embodiment, as shown in FIGS. 14 and 15, an electroluminescent (EL) plate 51 is integrated as a light emitting element on the inner surface of the shield member 13 of the corona discharge device 12. The EL plate 51 may be installed at a position as shown in FIG. 19 or 20.

By doing so, the device can be made smaller.

FIG. 21 shows still another embodiment of the present invention, and the same parts as in the previous embodiment are given the same reference numerals and will be described. In this embodiment, the insulating blocks 18 and 19 are attached to both ends of the shield member 13 using screws 55 instead of screws 55 as shown in FIG.
As shown in the figure, a notch 56 is provided at the end of the shield member 13.
At the same time, an engagement protrusion 57 that engages with the notch 56 is formed on the back surface of the insulating block 18, 19.

Then, as shown in FIG. 22, the insulating blocks 18 and 19 are engaged with the notches 56 of the shield member 13 via the engagement protrusions 57.
19 can be easily attached to both ends of the shield member 13.

In addition, in FIG. 21, 58 and 59 respectively indicate a projection provided on the insulating block and an engagement hole bored in the shield member, and the movement of the insulating block 18 and 19 is caused by these projections 58 and the shield member 59. is prevented.

Further, in this embodiment, the insulating blocks 18 and 19 are provided with a lid 60, but the lid 60 is not a separate body as shown in FIG. 24, but is shown in FIG. As shown, they are integrally formed via a hinge portion 60a.

Roughly speaking, in this embodiment, in order to fix the end of the discharge wire 20 to the insulating block 18, 19, a metal fixed terminal 61 is attached to the base end of the discharge wire 20, as shown in FIG.
Instead of planting the terminal 61 in the insulating block 18.19 and hooking the washer 62 fixed to the end of the discharge wire 20, as shown in FIG.
9, the washer 62 fixed to the end of the discharge wire 20 is hooked onto the protrusion 63 protruding from the lid body 60 and engaged with the protrusion 63, as shown in FIG. The mating cylinder 64 secures the end of the discharge wire 20 to the end of the insulating block 18, 19 by clamping the washer 62, as shown in FIG.

However, in addition to this, as shown in FIG.
With the end of the discharge wire 20 placed on the lid body 60,
The third
The ends of the discharge wire 20 may be fixed to the insulating blocks 18, 19 by pinching as shown in FIG.

Further, in this embodiment, the rail 70 for mounting the corona discharge device 12 on the main body of the copying machine is formed of a separate member from the shield member 13, as shown in FIG. 31, and is attached to the shield member 13 by welding or the like. Rather than being fixed, it is formed integrally with the shield member 13, as shown in FIG. That is, by cutting out the ceiling wall 16 of the shield member 13 as shown in FIG. 33 and bending it outward into a U-shaped cross section, the rail 70
is formed integrally with the shield member 13.

[Effect of the Invention J] This invention has the above-described structure and operation, and even when a sheet-like discharge product removal member such as an activated carbon sheet absorbs moisture and deforms, uneven discharge and abnormal discharge can be prevented from occurring. In addition, when the sheet-shaped discharge product removal member such as an activated carbon sheet reaches the end of its life, only the discharge product removal member can be easily replaced, reducing the running cost of the device. I can do it.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a roller discharging device according to an embodiment of the present invention, Fig. 2 is a perspective view showing a shield member, Fig. 3 is a perspective view showing an activated carbon sheet, and Fig. 4 is a perspective view showing a presser member. 5 is a sectional view of the insulating block portion of FIG. 1, FIG. 6 is a sectional view of the shield member portion of FIG. 1, and FIG. 7 is an electronic diagram to which the corona discharge device according to the present invention can be applied. FIG. 8 is a sectional view showing the operation of the present invention, FIG. 9 and FIG. 10 are plan views showing other examples of ventilation holes, and FIG. 12 is a configuration diagram showing a copying machine, FIG. 13 is a sectional view showing an air flow in a corona discharge device, FIG. 14 and
5 is a cross-sectional view and a plan view showing still another embodiment of the present invention, FIG. 16 is a block diagram showing a copying machine, and FIGS. 17 and 18 are block diagrams showing a combination of an exposure device and a charging device, respectively. , FIGS. 19 and 20 are cross-sectional views showing a modification of this example, and FIGS. 21 and 22 are a perspective view and an exploded perspective view showing still another embodiment of the present invention.
3 is a perspective view showing a conventional example, FIG. 24 is a perspective view showing a different conventional example, FIG. 25 is a perspective view showing still another embodiment of the present invention, and FIG. 26 shows a conventional device. 27 and 28 are exploded perspective views and sectional views showing other embodiments of the present invention; FIGS. 29 and 30 are exploded perspective views and sectional views showing modifications of this embodiment; FIG. 31 is a sectional view showing a conventional device, and FIGS. 32 and 33 are a perspective view and a sectional view showing still other embodiments of the present invention. [Explanation of symbols] 12...Corona discharge device 13...Shield member 18.19...Insulation block 20...Discharge wire 24...Activated carbon sheet 28-...Press member 12, corona discharge device special Applicant Fuji Xerox Co., Ltd. Representative Patent Attorney Tomohiro Nakamura (1 other person) Figure 27 Figure 4 Figure 10 Prisoner 0 Figure Figure 11 Prisoner 12 Figure Figure 1 13 Figure L Figure 14 Figure 0 3 Figure 15 Figure 1 Figure 21 Figure 22 Figure 16 Prisoner Figure 17 Figure 18 Figure 19 Figure 20 Figure 23 Figure 24 Figure 25 Figure 26 Figure 27 Figure 30 Figure 31 Figure 0 " Figure 29 Figure 33

Claims (1)

[Claims] In a corona discharge device consisting of a discharge wire stretched between a pair of insulating members and a shield member placed opposite to the discharge wire, a large number of ventilation holes are provided on the entire surface of the shield member. A corona discharge characterized in that the outer surface of the shield member is covered with a sheet-like discharge product removing member, and the sheet-like discharge product removing member is held on the outer surface side of the shield member by a pressing member. Device.