JPH05216379A - Cleaning device and manufacture of toner recovery roller provided on the device - Google Patents

Abstract

PURPOSE:To provide a cleaning device of simple structute, which hardly cause surface staining on an image by excellently recovering stuck material, etc., into which a charge is injected, besides toner, reversely charged toner, paper powder and talc. CONSTITUTION:Two conductors 24A and 24B are provided on a toner recovery roller 18 which rotates in contact with a cleaning brush 17 to electrostatically attract and recover the toner, etc., attracted to the cleaning brush 17, and a constitution that the voltages of different polarities are applied on respective conductors 24A and 24B, is adopted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device and a method of manufacturing a toner recovery roller provided in the cleaning device.

[0002]

2. Description of the Related Art In an image forming apparatus such as a copying machine, a facsimile or a printer, an electrostatic latent image is formed on a latent image carrier, and the electrostatic latent image is visualized as a toner image. After the transfer of the image, the toner that did not contribute to the transfer, and other foreign substances such as paper dust and talc that are attached to the surface of the latent image bearing member are adhered. A cleaning device removes the latent image carrier from the latent image carrier and collects it.

In a cleaning device that achieves such a function, for example, a cleaning brush such as a conductive fur brush or a magnetic brush is used, toner is removed from the cleaning brush directly or through a toner collecting roller. Apply a bias voltage of opposite polarity to electrostatically attract the above-mentioned deposits to the side of the cleaning brush to remove them from the latent image carrier, and then collect the deposits attached to the cleaning brush on the toner collecting roller. I have to.

Among the adhered substances removed by such a cleaning device, for example, with respect to the toner, in the transfer process of the toner image or the like, some toner is charged to the opposite polarity to the original charge polarity. Even if such toner can be removed from the surface of the latent image carrier by the mechanical brushing action of the cleaning brush of the above-mentioned cleaning device, the reversely charged toner adhering to the cleaning brush can be recovered by the toner recovery. Difficult to collect to the roller. Such toner may adhere to the surface of the latent image carrier again from the cleaning brush, which may cause cleaning failure. Foreign matter such as paper dust or talc that is charged to the same polarity as the toner in the charging series, but if it is charged to the opposite polarity and is charged to the opposite polarity, it is difficult to collect them from the cleaning brush to the toner collection roller. Become.

Therefore, for example, as shown in Japanese Patent Publication No. 2-42230 and US Pat. No. 4,999,679, a pair of cleaning brushes are provided, and a toner recovery roller is attached to each of them. Then, a voltage having a polarity opposite to the original charging polarity of the toner is applied to one of the toner collecting rollers, and a voltage having the same polarity as the original charging polarity of the toner is applied to the other toner collecting roller. It has been proposed to remove and collect the toner and other foreign matters that are charged to the opposite polarity together with the toner and other foreign matters that are charged to the opposite polarity.

In such an example, since two toner recovery rollers are required, the structure of the cleaning device is likely to be complicated, and the cost increases.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to make it possible to satisfactorily collect toner, reversely charged toner, paper powder, talc, and other adhering substances that have been injected with electric charges on a toner recovery roller, and An object of the present invention is to provide a low-cost cleaning device having a simple structure, which is unlikely to cause upper surface soiling. Another object of the present invention is to provide a method for manufacturing a toner recovery roller included in the cleaning device.

[0008]

In order to achieve the above-mentioned object, the present invention rubs against the surface of a latent image bearing member and, after the toner image transfer step, removes toner and other toner remaining on the surface. A cleaning brush that electrostatically removes and collects adhered substances including foreign matter, and a toner recovery that electrostatically adsorbs and collects the adhered substances on the cleaning brush by rotating while contacting this cleaning brush. And a roller for collecting toner, of which a toner collecting roller is provided as a toner collecting roller having at least two divided conductors on the surface side, and the conductors are insulated from each other. The present invention proposes a configuration in which the deposits having different electrical characteristics are shared by the conductors and a voltage to which electrostatic adsorption is applied is applied to each of the conductors.

Of the two conductors, any one of these conductors extends annularly on one end side of the toner recovery roller, and the other conductor annularly on the other end side of the roller. It is effective to use a conductor that extends from each annular portion and extends in a comb-teeth shape in the axial direction of the toner recovery roller from each annular portion toward the other annular portion.

Further, it is effective that each conductor is a conductor spirally formed on the surface of the toner collecting roller.

Further, it is effective to use the annular portion of the conductor as the voltage applying portion.

Further, by rubbing against the surface of the latent image carrier,
After the toner image transfer step, a cleaning brush that electrostatically removes and collects adhered substances including toner and other foreign matters remaining on the surface of the surface, and a cleaning brush that comes in contact with the cleaning brush and rotates. A toner recovery roller that electrostatically adsorbs and collects the adhering substances of the cleaning brush, and the toner recovery roller of which is provided with at least two divided conductors on the surface side thereof. A conductor that is configured as a recovery roller and that is electrically insulated from each other and to which a voltage capable of electrostatically adsorbing the adhering substances having different electrical characteristics is shared by each conductor and applied. In the method for manufacturing the toner recovery roller of the cleaning device, the surface of the roller having an insulating layer is coated with a metal thin film by plating,
After that, the unnecessary portion of the metal plating layer is removed by an etching process, and then the roller surface is covered with an insulating resin layer and the surface is polished to expose the metal portion or leave the insulating resin layer on the metal portion. A method for manufacturing a toner recovery roller is proposed.

[0013]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 shows a structure for collecting adhering substances such as toner in a cleaning device according to an embodiment of the present invention. To explain this, the entire structure of the cleaning device will be clarified below. deep.

In FIG. 2, reference numeral 1 is a constitutional example of a latent image carrier, which is a photosensitive member composed of an endless belt. The photosensitive member 1 is a transfer backup roller 2, a separation backup roller 3, a cleaning backup roller. 4, the support roller 5 and other support rollers (not shown) are wound around and driven to rotate in the direction of arrow a.

On the surface of the photoconductor 1, known charging, exposure,
A toner image is formed by development and the like, and this toner image is transferred to the recording medium 8 made of, for example, plain paper by the action of the transfer charger 6. After this transfer, the recording medium 8 is separated from the photoconductor 1 under the action of the separation charger 7, and after the separation, is conveyed by the conveyor belt 9 and discharged to the outside of the image forming apparatus through a fixing device (not shown). It Reference numeral 11 indicates a carrier tank, the inside of which is in a negative pressure state by a suction fan, and air enters through a hole on the left side of the drawing. In such a suction state, the recording medium 8 is conveyed while being attracted to the side of the conveyor belt 9.

Reference numeral 12 is a pre-cleaning charger, and reference numeral 13 is a photoconductor charge-removing lamp. Light from the charge-removing lamp 13 can reach the photoconductor 1, and each transfer The separation / cleaning area is irradiated. The photoconductor 1 is semitransparent so that the light from the lamp 13 can reach the photoconductive layer. Reference numeral 14 is a filter, which cuts out unnecessary components of the light traveling to the photoconductor.

Here, the cleaning device 1 is unitized above the photoconductor 1 so as to face it.
5 are provided. In the unit casing 16 of the cleaning device 15, a conductive cleaning brush 17, a toner collecting roller 18, and a scraping blade 19 are provided.
The toner conveying screw member 20 and the like are provided at the illustrated positions. Reference numeral 21 is a filter for releasing the pressure inside the unit.

The cleaning brush 17 is rotatably driven in the direction of the arrow shown in the figure. When the cleaning brush 17 is rubbed against the surface of the photosensitive member 1, the toner remaining on the surface after the toner transfer step and other The foreign matter such as paper dust and talc is electrostatically removed from the surface and collected.
In the present invention, the cleaning brush (fur brush) may be replaced with a magnetic brush using a cleaning agent instead of the cleaning brush (fur brush).

The deposits electrostatically adsorbed and collected on the side of the cleaning brush 17 are further cleaned.
Is electrostatically adsorbed by the toner collecting roller 18 rotating in contact with the toner collecting roller 18 and collected by this roller portion. Then, the collected adhered matter is further removed by the scraping blade 19.
The toner that is scraped off from the surface of the roller 18 and is scraped off is carried outside the cleaning device by the toner carrying screw member 20. The reference numeral 22 is a flicker member.

Here, returning to FIG. 1, the feature of the present invention is that the toner collecting roller 18 rotating in contact with the cleaning brush 17 is divided into at least two parts on the surface side. The toner recovery roller is provided with a conductor, and the conductors are insulated from each other, and the voltage that can electrostatically adsorb deposits having different electrical characteristics is shared by the conductors. It is a point to be a conductor to be applied. Although the conductors are provided on the surface of the toner collecting roller 18, these conductors may be exposed on the surface of the toner collecting roller 18, and these conductors are covered with an insulating resin layer or the like. May be.

FIG. 3 shows an example of the structure of the toner collecting roller. A roller 22 which is a base of the toner collecting roller 18 is made of a metal such as aluminum or stainless steel, and has a first conductor 24A shown by diagonal lines and a satin-finished surface on the surface thereof through an insulating layer described later. The second conductors 24B are formed in layers.

In each of the conductors 24A and 24B, one conductor 24A extends annularly on one end side of the toner collecting roller 18, and the other conductor 24B also annularly extends on the other end side of the toner collecting roller 18. It is extended.
Assuming that the respective annular portions are denoted by reference numerals 24A ₁ and 24B ₁ , the respective conductors extend from the respective annular portions 24A ₁ and 24B ₁ toward the respective annular portions in a comb-teeth shape in the axial direction of the roller. It is a good conductor. An insulator 24C (white portion) is formed between these comb teeth so as to be folded back at both ends, and the insulator 24C causes the comb teeth of both conductors to be insulated from each other. ing.

Here, the annular portions 24A ₁ and 24B ₁ at both ends are exposed on the surface of the toner collecting roller 18, and a voltage is applied to each of the annular portions 24A ₁ and 24B ₁ as shown in FIG. The brush terminals 25 and 26 for applying are in contact with each other. As shown in FIG. 2, the brush terminals 25 and 26 are fixed to the terminal fixing portion 27 on the main body of the cleaning device with screws or the like. As described above, in this example, the annular portions 24A ₁ and 24B ₁ are voltage applying portions.

The conductors 24A and 24B are connected to the conductors 24A and 24B via the brush terminals 25 and 26, for example, as shown in Table 1 below.
Voltages of different characteristics are applied.

[0026]

[Table 1]

In the table, DC is a DC voltage and AC is an AC voltage. DC also includes zeros and AC also includes pulse waves.

The characteristics of the voltage to be applied depend on the function required of the toner collecting roller 18.
For example, the conductor 24A electrostatically adsorbs and collects positively charged toner, paper powder, talc, etc., and the conductor 24B
When electrostatically attracting and collecting toner or the like that has been charged in the opposite negative polarity, negative DC is applied to the former conductor 24A and positive DC is applied to the latter conductor 24B. To do. In this case, each brush terminal 25, 26 shown in FIG. 1 is connected to a DC voltage power supply (not shown) corresponding to each polarity. In any case, in this example, toner or the like in which the negative charge is injected by the one conductor 24A can be immediately electrostatically adsorbed by the other conductor 24B.

Some toners have the same polarity but have different charge amounts. By applying voltages having the same polarity and different values to both conductors 24A and 24B, such toners having different electric charge amounts, in other words, toners having different electrical characteristics, etc. are provided for each conductor. It is possible to share and electrostatically adsorb. In the present invention, such a series of functions can be performed by one toner collecting roller, and the configuration of the cleaning device can be further simplified.

Here, FIGS. 4 and 5 show a second embodiment according to the present invention.
FIG. 3 is an enlarged cross-sectional view schematically showing a linearly extended type of toner recovery roller, and the toner recovery roller configured in this way can be manufactured as follows.

First, in FIG. 4, an insulating resin layer 23 such as acrylic or polycarbonate is formed on the surface of a metal roller 22 such as aluminum or stainless steel, which serves as a base.
Is formed by a method such as coating. In this way, a roller having an insulating layer on the surface is formed, and then the surface is once polished and smoothed, and then the insulating resin layer 23 is plated to coat the metal with a metal thin film layer. To form. A good conductor such as copper is desirable as the metal to be plated.

After that, an unnecessary portion of the metal plating layer is removed by etching to form an electrode pattern composed of two conductors as shown in FIG. An insulating resin layer 24C is further covered on the electrode pattern on the roller surface by a coating method, a spraying method, or the like, and the surface is polished to expose the metal portions to expose the conductors 24A and 24B. Thus, the metal pattern composed of the conductors 24A and 24B is exposed on the roller surface as shown in FIG. Further, the insulating resin layer 24C can be left on the metal portion of the metal pattern, and the toner collecting roller 18 is shown in FIG.

As the toner collecting roller, one having a metal pattern exposed as shown in FIG. 5 and one having a metal pattern exposed as shown in FIG.
Either insulating layer 24C that leaves each conductor 24A, 24B covered can be used.

Although the conductors 24A and 24B form a conductive layer, the pattern shown by this conductive layer is exposed. When the one shown in FIG. 5 is used, the initial cleaning property is improved, but the edges of the conductive layers 24A and 24B are improved. As a result, the scraping blade 19 (FIG. 2) is likely to be scratched, and it may be difficult to maintain the cleaning characteristics with time. From this point of view, the one shown in FIG. 4 is more advantageous.

Here, referring to FIG. 4, the action of the electric field between the cleaning brush 17 and the toner collecting roller 18,
To describe the cleaning property, the first conductor 24A
Is a positive voltage, and the second conductor 24B is a negative voltage,
As applied by the voltage power supplies E ₁ and E ₂ , respectively,
With this application, as shown in the left half of the figure, both conductors 2
Electric lines of force (arrows) from the conductor 24A to the conductor 24B are generated between the conductors 4A and 24B.

On the other hand, when the cleaning brush 17 comes into contact with the surface of the insulating layer 24C, the bristles of the brush become counter electrodes, and the direction of the lines of electric force changes. The brush 17
Is made of a conductive fiber, to which a bias voltage having a polarity opposite to that of the toner is applied by a voltage power source E ₃ . For example, when the toner is positively charged, a negative bias voltage is applied.

The toner charged to the positive polarity is the conductor 2
It moves to the toner collection roller 18 side along the line of electric force toward 4B, and is electrostatically adsorbed to this roller side.
Further, the toner charged to the opposite polarity, the paper dust, the talc, and the like move to the roller side by the electric force line in the opposite direction, and are electrostatically adsorbed to the toner collecting roller.

Even when an AC bias is applied to the toner collecting roller 18, it is possible to electrostatically attract the adhering substances charged to both polarities. However, the method shown in FIG. 4 can further improve the collectability of toner. this is,
When an AC bias is applied, a change in the electric field (direction of the line of electric force) at the same place on the toner recovery roller receives repulsive force on the particles of the toner and the like that were heading toward the toner recovery roller side, and again moves to the cleaning brush side. It is thought that this is because it may start moving toward you.

The method according to the present invention, particularly the toner recovery method shown in FIG. 4, is formed by applying voltages having different polarities.
It has also been confirmed by experiments that the recovery rate of particles charged with a polarity opposite to the original charging polarity of the toner is higher than that of a system in which the toner recovery roller of the book is brought into contact with a cleaning brush to recover the toner. The reason for this is that in the case of a system using two toner collecting rollers, the second toner collecting roller reaches the cleaning section again while the particles injected with electric charges are not collected and remain on the cleaning brush.
This reattaches to the photoconductor and causes scumming.
In the case of the method shown in (2), it is presumed that even if the particles are subjected to charge injection, they are adsorbed by the adjacent conductors.

According to an experiment conducted by the present inventor, a cleaning brush 17 is used, in which a photosensitive member having a characteristic of being negatively charged is used as a latent image carrier, and a toner having a characteristic of being positively charged is used as a developer. The voltage applied to -150
V to −350V, and the voltage applied to the conductor 24A is −
It has been confirmed that when the voltage applied to the conductor 24B is set to 250 V to −600 V and the voltage applied to the conductor 24B is set to +50 V to +250 V, the removability of deposits is improved.

The conductors may be formed in a spiral shape on the toner collecting roller surface side. In this case, a spiral conductive layer pattern is formed on the roller surface side. become. In either case, the width of the pattern is preferably about 0.5 to 5 mm. However, when the peripheral speed difference between the toner recovery roller and the cleaning brush is large, the larger the width, the wider the width. Is preferred. The pattern interval is 0.5
It is better to be as narrow as possible such as mm or more, but if this pattern interval is too narrow, current leakage between patterns will occur and it will cause a decrease in cleaning performance, so it is desirable to set a suitable interval. ..

In each of the examples described above, the cleaning brush 1
A bias voltage having a polarity opposite to the original charging polarity of the toner is applied to the cleaning brush 7, but the bias voltage is not applied to the cleaning brush 17, and the conductors 24A, 24A,
A bias voltage may be applied to 24B as described above, thereby forming an electric field between the cleaning brush 17 and the photoconductor 1. According to this configuration, the photoconductor 1
It is possible to electrostatically transfer both of the above-mentioned positively charged toner and other attached matter and the negatively charged toner and other attached matter to the cleaning brush 17, thus further improving the cleaning performance for the photoconductor 1. It can be expected to enhance the effect.

As shown in FIG. 3, the length L is
If called the effective length of the toner collecting roller, this is determined by the following magnitude relation with the width length of the scraping blade 19 (FIG. 2) and the axial length of the cleaning brush 17. Is desirable. L> blade width length> brush length.

[0044]

According to the cleaning device of the first aspect, not only the toner which is normally charged but also the toner which is charged to the opposite polarity to the original polarity and other paper dust and talc It is possible to satisfactorily collect foreign matter such as the toner on the toner collecting roller. Further, it is possible to efficiently collect the toner or the like that has been injected with electric charges by the toner collecting roller itself, and it is possible to prevent the background stain on the image. Furthermore, since one toner recovery roller is sufficient, the configuration of this type of cleaning device can be further simplified.

According to the cleaning device of the second aspect, the toner having the electric charges injected can be immediately recovered by the comb-tooth-shaped conductor portions adjacent to each other, and the toner can be collected on the cleaning brush or the like. Migration is less likely to occur.

According to the cleaning device of the third aspect, the method of forming the two conductors becomes simpler.

According to the cleaning device of the fourth aspect, the voltage can be applied to each conductor without interruption.

According to the method of manufacturing the toner collecting roller of the fifth aspect, the conductor pattern can be manufactured relatively easily.

[Brief description of drawings]

FIG. 1 is a perspective view of a toner and the like collecting component in a cleaning device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a cleaning device, a belt photosensitive member, and the like according to an embodiment of the present invention.

FIG. 3 is a perspective view showing a configuration example of a toner recovery roller.

FIG. 4 is an enlarged cross-sectional view schematically showing the toner recovery roller in a flat state.

FIG. 5 is an enlarged cross-sectional view schematically showing another example of a toner recovery roller in a flat state.

[Explanation of symbols]

1 Belt-Shaped Photoreceptor as Latent Image Carrier 15 Cleaning Device 17 Cleaning Brush 18 Toner Collection Roller 22 Roller 24A Conductor 24B Conductor 24C Insulating Resin Layer 24A ₁ Annular Section 24B ₁ Annular Section

Claims (5)

[Claims] 1. A surface of a latent image bearing member is rubbed against the surface of the latent image bearing member, and after the toner image transfer step, the adhered substances including toner and other foreign matter remaining on the surface are electrostatically removed from the surface. And a toner collecting roller that rotates while contacting with the cleaning brush to electrostatically adsorb the adhering substances on the cleaning brush and collect the toner. Of these, the toner collecting roller is The toner collecting roller is provided with at least two divided conductors on the surface side, and the conductors are insulated from each other and the deposits having different electric characteristics are provided for each conductor. A cleaning device, characterized in that conductors to which a voltage that can be shared and electrostatically attracted is applied are provided. 2. The two conductors, of which any one conductor extends annularly on one end side of the toner collecting roller, and the other conductor annularly on the other end side of the roller. The cleaning device according to claim 1, wherein the conductor extends from each annular portion and extends in a comb-teeth shape in the axial direction of the toner recovery roller toward the corresponding annular portion. 3. The cleaning device according to claim 1, wherein each conductor is a conductor formed in a spiral shape on the surface side of the toner recovery roller. 4. The cleaning device according to claim 2, wherein each annular portion is a voltage applying portion. 5. The surface of the latent image bearing member is rubbed against the surface of the latent image bearing member, and after the toner image transfer step, the foreign matter remaining on the surface is electrostatically removed from the surface. And a toner collecting roller that rotates while contacting with the cleaning brush to electrostatically adsorb the adhering substances on the cleaning brush and collect the toner. Of these, the toner collecting roller is The toner collecting roller is provided with at least two divided conductors on the surface side, and the conductors are insulated from each other and the deposits having different electric characteristics are provided for each conductor. In the method of manufacturing the toner recovery roller of the cleaning device, which is a conductor to which a voltage that can be shared and electrostatically attracted is applied, in the method of manufacturing the toner recovery roller, the surface of the roller having an insulating layer is coated with The thin film is plated to cover it, and then the unnecessary portion of the metal plating layer is removed by etching, and then the roller surface is covered with an insulating resin layer and the surface is polished to expose the metal part, or A method for manufacturing a toner recovery roller, characterized in that an insulating resin layer is left on a metal part.