JPH0434527Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a corona discharge device equipped with a cleaner in an electrostatographic copying machine or the like.

[Conventional technology]

Corona discharge devices in electrostatographic copying machines, etc.
Toner, dust, and the like floating inside the copying machine and other devices are oxidized by ozone generated during discharge, and adhere to discharge electrodes made of wires and other surfaces. This deposit on the discharge electrode, shield case, etc. accumulates every time copying is performed, reducing the discharge efficiency, causing uneven discharge, and deteriorating the quality of the copied image. Therefore, it is necessary to properly clean the discharge electrode.

Corona discharge devices equipped with a cleaner have already been proposed, but in general, in conventional ones, a discharge electrode is stretched between supporting members fixed at both ends in a shield case with a concave cross section, and the discharge electrode is contacted. A cleaning body that slides along the discharge electrode is provided, and by sliding the cleaning body back and forth along the discharge electrode, the deposits adhering to the discharge electrode are wiped off. After the cleaning is completed, the cleaning body is kept close to one end of the shield case, but the cleaning body is in contact with the charging effective area of the discharge electrode even when it is in the stored position when not in use. I was getting used to it.

As shown in FIG. 8, this means has an effect on the charging of the photoreceptor by the cleaning body. In FIG. 8A, C is a shield case, and supporting members D and F are provided at both ends of the shield case. W is a discharge electrode made of a wire, and G is a cleaning body for the support member D. FIG. 8B shows the charging potential of the E photoreceptor.

As is clear from FIG. 8B, in the charging potential E in the effective charging area, the decreasing region L of the charging potential E at the end of the cleaning body G is smaller than the decreasing region L at the end on the supporting member F side. , the discharge electrode W in contact with the cleaning body G
becomes longer in proportion to the length of For this reason, there was a problem in that the usable range of the discharge electrode was shortened and the latent image formation at the end of the photoreceptor was affected.

In addition, the influence of the cleaning body G in contact with the discharge electrode W not only increases the area in which the charging potential E decreases, but also causes problems such as uneven charging and destabilization of the charging area. Furthermore, the position of the discharge electrode W is changed by cleaning body G that is in contact with it.
There was also the problem that the charged potential changed when the current was changed.

Attempts have therefore been made to eliminate these drawbacks. Specifically, while a guide plate is installed on the opposite side of the shield case to the opening side,
The main body frame on the opening side of the shield case has its tip directed from the opening side toward the opposite surface side, and is constantly urged by a spring from the opening side toward the opposite surface side, and is guided by the guide. A configuration has been proposed in which a cleaning body is provided, and guides are provided at both ends of the guide to bulge toward the photoreceptor and push up the cleaning body.

In this configuration, by repeatedly pulling out the shield case from the main body frame and pushing it in again, the cleaning body rubs against the discharge electrode to remove dust, toner, etc., and after cleaning is completed, When the shield case is pushed into the main body frame and set, the cleaning body rides on the guide in the insulating member and separates from the discharge electrode (see Japanese Utility Model Application No. 54-36432).

[Problem that the invention attempts to solve]

The proposal published in the above-mentioned publication (hereinafter referred to as prior art) does successfully avoid the drawbacks of the conventional method in which the cleaning body is in constant contact with the discharge electrode, but it also has the following new features: It ended up having some drawbacks. That is, since the cleaning body is provided on the main body frame on the opening side of the shield case (on the side where the photoreceptor is present), the amount of protrusion of the guide for retracting the cleaning body from the discharge electrode cannot be increased, and cleaning It has the fatal disadvantage of not being able to effectively separate the body from the discharge electrode. This is because, as a practical matter, the distance between the shield case and the photoreceptor can only be set to a small distance.

Furthermore, since the cleaning body is fixedly attached to the main body frame, there is a structural disadvantage that it is difficult to replace the cleaning body, which is a consumable part.

Furthermore, since it is necessary to insert and remove the shield case from the main body frame each time cleaning is performed, the electrode pins of the shield case and the jack of the power circuit inside the main body are repeatedly disconnected, which may lead to premature contact failure. be.

Therefore, the present invention is an attempt to effectively eliminate the shortcomings of each of the conventional and prior art techniques, and the influence of the cleaning body on the discharge electrode is the same as in the prior art.
To provide a corona discharge device that can perform ideal charging by uniformly and appropriately charging a photoreceptor, and can easily replace a cleaning body.

[Means for solving problems]

In order to achieve the above-mentioned problems, the corona discharge device of the present invention has a discharge electrode stretched between supporting members provided at both ends of a shield case with a concave cross section, and A cleaning body for the discharge electrode is provided on the wall with the tip facing toward the opening side of the shield case and slidable along the wall, and the cleaning body can move the tip of the discharge electrode toward the opening side of the shield case when the cleaning body is not in use. The mounting part, which is biased in the sliding direction of the discharge electrode and placed in a position separated from the discharge electrode, is provided closer to the wall than the discharge electrode of the fixed body such as the support member.

[Effect]

When the cleaning body of the corona discharge device configured as described above is slid along the wall within the shield case, the cleaning body comes into contact with the discharge electrode over the entire length and adheres to the discharge electrode. Wipe off any toner, dust, etc.

When the cleaning is finished and the cleaning body is moved along the wall to the mounting section, the mounting section biases the tip of the cleaning body in the sliding direction so as to place the cleaning body spaced apart from the discharge electrode. to work. Therefore, unlike the conventional method, the cleaning body can be separated from the discharge electrode after cleaning is completed without coming into contact with the discharge electrode. is made equal to the lowering area l at the end on the supporting member side, so that the usable range of the discharge electrode is not shortened.

In this way, since the cleaning body slides along the wall, when it is not in use, its tip only deviates in the sliding direction and becomes separated from the discharge electrode, and basically the cleaning body itself is Unlike the conventional method, the electrode does not move far from or near the discharge electrode from beginning to end, and its relative position does not change over the entire length.

〔Example〕

First embodiment of the corona discharge device of the present invention
Figure 4 will be explained.

In Figure 1, 1 is a shield case made of metal such as stainless steel and has a concave cross section.
Support members 2a and 2b are fixed inside both ends as fixed bodies made of an insulating material such as synthetic resin. Reference numeral 3 denotes a wire discharge electrode stretched between the support members 2a and 2b.

4 is the opening of the shield case 1, 5 is the opening 4
As shown in FIG. 3, a long hole 6 is provided on the top wall of the shield case 1 facing the support member 2a and 2b along almost the entire length between the support members 2a and 2b, and the end of the long hole 6 on the side of the support member 2a A cleaning body insertion hole 7 is provided in the width direction of the cleaning body in communication with the cleaning body.

Reference numeral 8 denotes a cleaning body slidably provided inside the shield case 1, which is attached to a mounting member 9 made of synthetic resin or the like.
The cleaning member 10 made of synthetic fibers or other fibers is planted upright in the shape of a brush. Reference numeral 11 denotes an operation plate (see Fig. 3) of the cleaning body 8 which is superimposed on the outer surface of the top wall 5 of the shield case 1, and is configured to a size that can cover almost the entire elongated hole 6, and a mounting member 9 is attached to one end of the operation plate. The cleaning body 8 is attached through it. 11
a is a knob on the operation panel 11; Reference numeral 12 denotes engagement recesses provided on both sides of the mounting member 9 in the width direction (see Fig. 4).
Both ends 6a of the elongated hole 6 are engaged with each other, and the cleaning body 8 is slid along the edge 6a using the operation plate 11.

To attach the cleaning body 8 to the shield case 1, insert the cleaning body 8 into the shield case 1 through the insertion hole 7, and insert the end edge 6a of the elongated hole 6 into the engagement recess 12.
This is done by engaging the

Reference numeral 13 denotes a protruding plate provided from the support member 2a in the same direction as the discharge electrode 3 on the side of the top wall 5 of the shield case 1 rather than the discharge electrode 3, thereby forming a mounting step portion 14 on the support member 2a. , cleaning member 10
from a working position perpendicular to the discharge electrode 3 to a non-working position in which the tip deviates approximately 90 degrees in the sliding direction.
The cleaning body 8 can be placed on the stage 14 by elastic deformation.

Reference numerals 15a and 15b are discharge area cut walls protruding from the end of the opening 4 of the shield case 1 in the same direction as the discharge electrode 3 on opposing surfaces of the support members 2a and 2b; Discharge effective area S
become.

16 is an introduction hole for the discharge electrode 3 provided in the support member 2a, 17 is a connection terminal fixed to the support member 2a and protruding from the outside thereof, and a coil attached to the end of the discharge electrode 3 is attached to the connection piece 18. Spring 19 is stopped. 20 is a discharge electrode 3 provided within the support member 2a.
The position of the discharge electrode 3 is adjusted by moving the position adjustment tool using a machine screw 21.

Cleaning of the discharge electrode 3 in this corona discharge device is carried out by holding the discharge electrode 3 between the cleaning members 10 and holding the knob 11a, as shown by the chain line in FIG. 1 and by the solid line in FIG. The cleaning body 8 is slid using the operation plate 11. When cleaning is finished, move the cleaning body 8 toward the protruding plate 13 and remove the cleaning member 1.
When the cleaning member 10 is brought into contact with the protruding plate 13 and the cleaning member 8 is pressed a little forcefully, the cleaning member 10 moves from the working position perpendicular to the discharge electrode 3, as shown by the solid line in FIG.
The distal end is elastically deformed to a non-working position in which the distal end is deflected by approximately 90 degrees in the sliding direction, and is placed on the mounting stage section 14 constituted by the protruding plate 13, and is separated from the discharge electrode 3.

Therefore, there is no object that comes into contact with the discharge electrode 3, and the influence on the charging of the discharge electrode 3 can be reduced, so that the drop in the charging potential of the discharge electrode 3 is reduced. In this embodiment, since the discharge area cut walls 15a, 15b are provided protruding from the support members 2a, 2b, the influence of the support members 2a, 2b on charging is reduced, and the charging effective area of both ends of the discharge electrode 3 is The potential decrease region is smaller than the decrease region l at the right end of the charged potential E shown in FIG. 8B.

As shown by the solid line in FIG. 1, when cleaning the cleaning body 8 placed on the stage 14, pull the cleaning body 8 a little forcefully through the operation panel 11 to remove it from the protruding plate 13. To separate. Then, the cleaning member 10 elastically returns to grip the discharge electrode 3.

In the above embodiments, fibers were used as the cleaning member 10, but any other material capable of cleaning the discharge electrode 3, such as sponge or felt, could be used as a plate, a plate, etc.
It can be used in the form of a wire or rod. Since the operation plate 11 also serves as a cover for the elongated hole 6, the operation plate 11 is made large enough to cover the entire elongated hole 6, but this can be done by making the cleaning body 8 operable. For example, the cleaning body 8 may be provided with a knob directly, or the operation plate 11 may be provided within the shield case 1.

FIG. 5 shows a second embodiment. In this embodiment, a mounting step 14 is formed on the top wall 5 side of the shield case 1 by cutting out a part of the support member 2a. Since the other configurations are the same as those of the first embodiment, the same reference numerals are given and detailed explanations are omitted.

Also in this embodiment, since the cleaning body 8 is separated from the discharge electrode 3 when not in use and moves out of the effective discharge area S, the potential drop in the discharge electrode 3 can be reduced.

FIG. 6 shows a third embodiment. In this embodiment, the discharge area cut walls 15a and 15b of the first embodiment are removed from the support member 2a, and the other components are the same as those of the first embodiment, so they are designated by the same reference numerals.

In this embodiment, the cleaning body 8 when not in use is within the discharge effective area S of the discharge electrode 3 together with the protrusion plate 13, but is separated from the discharge electrode 3.
The effect of this on the charging of the photoreceptor is extremely small, and the potential drop range is comparable to the drop range l at the right end of the charging potential E shown in FIG. 8B.

FIG. 7 shows a fourth embodiment, in which a cleaning body 8 is swingably attached to a bearing member 23 protruding from the operation plate 11, and the cleaning body 8 is biased toward the support member 2a by a spring 24. has been done. Since the other configurations are the same as those of the first embodiment, they are designated by the same reference numerals.

In this embodiment, if the cleaning body 8 is brought into contact with the protrusion plate 13 and pushed slightly strongly after cleaning is completed, the spring 24
The cleaning body 8 rotates against the force of , is placed on the stage 14, and is separated from the discharge electrode 3. During cleaning, when the cleaning body 8 is separated from the protruding plate 13, the cleaning body 8 is returned to its original state by the force of the spring 24, and the cleaning member 10 comes into contact with the discharge electrode 3. When not in use, the entire cleaning body 8 is rotated and placed on the stage 14, and elastic deformation of the cleaning member 10 is not required, so the return of the cleaning member 10 during cleaning is more secure. be able to.

In each of the embodiments described above, the support member 2a is used as a fixed body on which the mounting stage 14 is provided, but it is also possible to provide another fixed body inside the support member 2a and provide the mounting stage 14 thereon. It is possible.

[Effect of idea]

Since the present invention is configured as described above, it produces the effects described below.

The cleaning body is installed on the wall opposite to the opening side of the shield case with the tip facing toward the opening side of the shield case, and is slidable along the wall. During use, the cleaning body is placed on the mounting section with the tip biased in the sliding direction, separated from the discharge electrode, so after cleaning is completed, the cleaning body must be separated without coming into contact with the discharge electrode. In the charging potential of the effective charging area, the charging potential reduction area L at the end on the cleaning body side is made equal to the reduction area L at the end on the support member side,
Not only does it not shorten the usable range of the discharge electrode, but when the cleaning body is not in use, the tip of the cleaning body simply deviates in the sliding direction and separates from the discharge electrode. Basically, the cleaning body itself is , unlike the prior art, the shield case does not move near or far from the discharge electrode from beginning to end and its relative position does not change over the entire length, so this shield case can be installed as close as possible to the photoreceptor, and the shield case can be installed uniformly and The appropriate amount of charging could be performed, and the synergistic effect of these factors made ideal charging possible. Moreover, since the cleaning body is in a position where its tip is biased in the sliding direction between the discharge electrode and the wall when not in use, the distance between the discharge electrode and the wall can be shortened as much as possible, making it compact. A discharge device is obtained.

In addition, cleaning the discharge electrode is done by simply sliding the cleaning body along the wall of the shield case, so unlike the prior art where the shield case is inserted and removed every time cleaning is done, it does not take long periods of time. The connection between the electrode pins of the shield case and the jack of the power supply circuit inside the main body is maintained well, and the above-mentioned ideal charging can be well maintained for a long period of time, resulting in high quality copy images.

Furthermore, since the cleaning element is installed in the shield case, unlike the prior art where it is fixedly installed on the main body frame, the cleaning element can be replaced outside the main body frame without being obstructed by the main body frame. The replacement work can now be done efficiently and very easily.

[Brief explanation of drawings]

1 to 4 show a first embodiment of the present invention, FIG. 1 is a sectional front view, FIG. 2 is a perspective view, FIG. 3 is a perspective view of the cleaning body separated, and FIG. 4 is a cleaning body. side view,
5 is a sectional view of the main part of the second embodiment, FIG. 6 is a sectional view of the main part of the third embodiment, FIG. 7 is a sectional view of the main part of the fourth embodiment, and FIG. B is a schematic diagram of a conventional example and a diagram showing its charged potential. DESCRIPTION OF SYMBOLS 1... Shield case, 2a, 2b... Support member, 3... Discharge electrode, 8... Cleaning body, 14... Placement step part.

Claims (1)

[Scope of utility model registration request] A discharge electrode is stretched between support members provided at both ends of a shield case with a concave cross section, and is placed on the wall opposite to the opening of the shield case with its tip facing the opening of the shield case. , and a cleaning body for the discharge electrode is provided so as to be slidable along the wall, and when the cleaning body is not in use, the tip thereof is biased in a sliding direction of the cleaning body so as to be separated from the discharge electrode. A corona discharge device, characterized in that a mounting portion to be placed is provided closer to the wall than a discharge electrode of a fixed body such as the support member.