JP6838702B2 - Charging device and image forming device - Google Patents

Description

The present invention relates to a charging device and an image forming device.

There are known chargers that use corona discharge to charge an object to be charged such as a photoconductor.

Here, Patent Document 1 proposes a charger having a structure for cleaning a discharge wire extending in the left-right direction inside the scorotron by moving a cleaning member in the left-right direction.

Further, Patent Document 2 proposes a charging device having a structure for cleaning wires and grids by reciprocating a cleaning member.

Japanese Unexamined Patent Publication No. 2014-1993777 Japanese Unexamined Patent Publication No. 06-025849

An object of the present invention is to provide a charging device and an image forming device capable of cleaning a wire while charging a charged body without stopping charging.

Claim 1 is
A wire that is stretched and charges the object to be charged by electric discharge,
A wire moving mechanism that moves the wire in the tension direction,
A grid arranged between the wire and the charged body to control the charge amount of the charged body, and
A portion that is arranged between the wire and the grid, is in contact with both the wire and the grid, is movable in the tensioning direction, and is responsible for charging the charged region and the wire in the charged body. A cleaning member that moves to a position away from the wire and slides in contact with the wire to clean the wire, and also cleans the grid by moving in the tension direction.
Charging characterized by having an application means for applying a voltage to charge the wire to be charged while the wire is moved by the wire moving mechanism and the wire is cleaned by the cleaning member. It is a device.

Claim 2
The wire has a ring shape
The charging device according to claim 1, wherein the wire moving mechanism circulates and moves the wire.

The charging device according to claim 2, wherein the outward path portion and the return path portion of the cyclically moving wire are arranged in a posture in which the distances from the charged body are equidistant from each other. ..

Claim 4
An image-holding member that holds a toner image through the processes of charging, exposure, and development while rotating, and transfers the toner image onto a transfer target.
The charging device according to any one of claims 1 to 3 , wherein the image-holding member is the charged body.
A transport device that transports paper and
A transfer device that transfers the toner image formed on the image-holding member onto the conveyed paper, and
The image forming apparatus is provided with a fixing device for fixing a toner image transferred on the paper onto the paper.

According to the charging device according to the first aspect and the image forming apparatus according to the fourth aspect, the wire can be cleaned while charging the object to be charged without stopping the charging.
Further, according to the charging device according to claim 1 and the image forming device according to claim 4, not only the wire can be cleaned during charging, but also the grid can be cleaned during the charging pause state.

According to the charging device of claim 2, the wire can be cleaned by circulating the wire in one direction without reciprocating the wire.

According to the charging device of claim 3, the charging performance equivalent to that of the charging device having a structure in which two fixing wires are suspended is realized.

It is a schematic diagram of the image forming apparatus as one Embodiment of this invention. It is a schematic diagram of a charger as a first example. It is a schematic diagram of a charger as a second example. It is a schematic diagram of a charger as a third example.

Hereinafter, embodiments of the present invention will be described.

FIG. 1 is a schematic view of an image forming apparatus as an embodiment of the present invention. The image forming apparatus 100 shown in FIG. 1 includes an embodiment of the charging apparatus of the present invention.

The image forming apparatus 100 includes a paper feeding unit 110, an image forming unit 120, and a winding unit 130.

A long roll paper P1 wound in a roll shape is mounted on the paper feed unit 110. The roll paper P1 mounted on the paper feed unit 110 is directed toward the image forming unit 120 by the rotation of the roll shaft 111 in the direction of the arrow A and the rotation of the delivery roll 112 by a drive source (not shown). It is sent out as continuous paper P in the direction.

In the image forming unit 120, the continuous paper P fed in the direction of the arrow X1 is conveyed in the direction of the arrow X2 by the conveying member 121, and an image is formed on the continuous paper P in the meantime.

The continuous paper P on which this image is formed is sent to the winding unit 130 in the direction of arrow X3, and is rotationally driven in the direction of arrow B by a drive source (not shown) via a buffer 132 for absorbing the speed difference. The roll paper P2 is wound around the roll shaft 131 to be formed.

The image forming unit 120 is provided with four image holders 11Y, 11M, 11C, and 11K, each of which rotates in the direction of the arrow Y. Here, Y, M, C, and K mean yellow, magenta, cyan, and black. On the four image holders 11Y, 11M, 11C, and 11K, each toner image is formed by toners of each color through the toner image forming process described below. Hereinafter, in the description common to each color, the symbols Y, M, C, and K indicating the color distinction will be omitted.

Each charger 12 and each developer 13 are provided around each image holder 11. Each charger 12 charges each image holder 11. Further, each developer 13 develops an electrostatic latent image formed on each image holder 11 with toner of each color. Further, an exposure device 14 is provided above the four image holders 11Y, 11M, 11C, and 11K. From the exposure device 14, each exposure light 141 modulated with image data corresponding to each color is irradiated toward each image holder 11. Then, on each image holder 11, a toner image of each color is formed by charging by each charging device 12, forming an electrostatic latent image by irradiating each exposure light 141 from the exposing device 14, and developing by each developing device 13. Each image holder 11 is formed and temporarily holds the formed toner image of each color. Here, each charger 12 corresponds to an example of the charging device of the present invention.

Further, the image forming unit 120 is provided with an intermediate transfer belt 21. The intermediate transfer belt 21 is an endless belt that is supported by a plurality of rolls 22 and circulates in the direction of the arrow Z along a path along the four image holders 11.

Each primary transfer roll 23 is provided at each position where the intermediate transfer belt 21 is sandwiched between the image holder 11 and the image holder 11. Then, each toner image temporarily held on each image holder 11 is transferred onto the intermediate transfer belt 21 by the action of each primary transfer roll 23. The toner image transferred onto the intermediate transfer belt 21 is carried in the direction of arrow Z by the intermediate transfer belt 21, and is transferred onto the continuous paper P by the action of the secondary transfer roll 24.

The toner image transferred onto the continuous paper P is carried to the continuous paper P and proceeds in the direction of arrow X2, and is sandwiched between the heating roll 31 and the pressure roll 32 constituting the fixing device 30 to heat and pressurize. The toner image is fixed on the continuous paper P. As a result, an image composed of the fixing toner image is formed on the continuous paper P. As described above, the continuous paper P on which this image is formed is fed to the winding unit 130 and wound up to become the roll paper P2.

The image forming apparatus 100 is further provided with a control unit 41 and an operation unit 41. The control unit 41 is in charge of overall control for realizing the above-mentioned image formation process in the image forming apparatus 100. Further, the control unit 41 receives a print instruction including image data transmitted from an external device, temporarily stores the print instruction, controls the exposure device 14 based on the image data, and causes the exposure device 14 to display the image. The exposure light 141 according to the data is generated.

Further, the operation unit 42 has a role of accepting an operation by the user and transmitting the user operation to the control unit 41. The control unit 41 controls the image forming apparatus 100 so that the operation corresponding to the user operation transmitted from the operation unit 42 is executed.

Here, the feature of this embodiment lies in the structure of the charger 12, and the structure of the charger 12 will be described below.

The image forming apparatus 100 shown in FIG. 1 is an apparatus for forming an image on continuous paper P. Therefore, once the operation is started, the operation continues for a long time. Therefore, the charger 12 also needs to continue to operate for a long time, and may need to be cleaned even during charging. The charger 12 described below is a charger devised so that the wire can be cleaned even during charging.

FIG. 2 is a schematic view of a charger as a first example. Here, FIG. 2 (A) is a plan view, and FIG. 2 (B) is a cross-sectional view. Although four chargers 12Y, 12M, 12C, and 12K are shown in FIG. 1, all of these chargers 12Y, 12M, 12C, and 12K have the same configuration, and in each of the drawings after FIG. , The symbols of Y, M, C, and K representing colors are omitted.

FIG. 2 shows the positional relationship between the image holder 11 and the charger 12. Further, FIG. 2 shows a charged region D of the image holder 11 that needs to be charged because an electrostatic latent image may be drawn. The role of the charger 12 is to charge the inside of the charged region D of the image holder 11.

The surface of the charger 12 other than the lower surface facing the image holder 11 side is covered with the cover member 1211. A grid 122, which is a porous electrode, is arranged on the lower surface facing the image holder 11. Further, the charger 13 is provided with a ring-shaped wire 123 that circulates and moves. The wire 123 is hung on the drive roll 124 and the tension roll 125 in a posture in which the wires 123 extend parallel to each other in the tension direction indicated by arrows K1-K2 and the distance between the wires 123 and the image holder 11 is the same. Has been passed.

A drive gear 126 is fixed to the drive roll 124 coaxially with the drive roll 124, and the drive gear 126 is provided with a drive force transmission mechanism (not shown) in which the rotational drive force from the motor 101 is a gear or the like. It is transmitted through. When the rotational driving force from the motor 101 is transmitted to the drive gear 126, the drive gear 126 rotates in the direction of arrow R, and the drive roll 124 also rotates in the direction of arrow R. Then, the wire 123 hung on the drive roll 124 circulates in the direction of the arrow R1.

Further, a tension applying member 138 is connected to the bearing 127 of the tension roll 125, and the tension roll 125 is urged away from the drive roll 124. As a result, tension is applied to the wire 123.

Here, the wire 123 is discharged by applying a voltage from the power supply 102 to charge the image holder 11. Further, a control voltage for controlling the charge amount of the image holder 11 is applied to the grid 122 by the power supply 102. In the case of this first example, since the outward path portion and the return path portion of the wire 123 are equidistant from the image holder 11, both the outward path portion and the return path portion carry the charge of the image holder 11, and 2 fixed wires are used. It achieves the same charging performance as the equipped charger.

Further, the charger 12 is provided with a cleaning member 129 for cleaning the wire 123. The cleaning member 129 is arranged at a position outside the charged region D in the tensioning direction (arrows K1-K2 direction) and is fixed in contact with the wire 123. Since the cleaning member 129 is arranged at a position outside the charged region D, it does not interfere with the charging of the image holder 11 due to the discharge of the wire 123, and the wire 123 circulates even during the charging operation. The wire 123 is cleaned by the movement. Here, the power supply 102 corresponds to an example of the application means referred to in the present invention.

In the case of the first example shown in FIG. 2, the cleaning member 129 is arranged at a position outside the charged region D in the tensioning direction (arrow K1-K2 direction), but in the tensioning direction (arrow K1). In the −K2 direction), even within the charged region D, the cleaning member 129 is placed on the upper part of the wire 123 at a position avoiding between the image holder 11 and the wire 133, for example, in contact with the wire 123 only from above. The cleaning member 129 may be arranged at a position avoiding between the charged region D of the image holder 11 and the portion of the wire 123 that bears the charge of the charged region D.

FIG. 3 is a schematic view of a charger as a second example. Here, FIG. 3 (A) is a side view, and FIG. 3 (B) is a cross-sectional view. In FIG. 3, the elements corresponding to each element of the charger of the first example shown in FIG. 2 are designated by the same reference numerals as those assigned in FIG. 2 for the sake of clarity, and the differences are shown. explain.

In the second electric device 12 of the second example shown in FIG. 3, the outward path portion and the return path portion of the ring-shaped wire 123 that circulates and moves are parallel to each other as in the first example shown in FIG. However, they are arranged vertically with respect to the image holder 11, and the distances from the image holder 11 are different from each other. Further, in the case of the charger 12 of the second example, the cleaning member 129 is arranged so as to be in sliding contact with the side of the outward path portion and the return path portion of the wire 123, which is separated from the image holder 11. In the case of this second example, since the outward path portion and the return path portion of the wire 123 are vertically arranged, the image holder 11 is charged only by one of the outward path portion and the return path portion, which is close to the image holder. The other, which is carried by the wire and is separated from the image holder 11, hardly contributes to charging. Therefore, in this second example, the cleaning member 129 is on the side of the outward path portion and the return path portion of the wire 123 that is separated from the image holder 11, and is in the tension direction indicated by the arrows K1-K2 shown in FIG. Is arranged inside the charged region D. In this case, a space for arranging the cleaning member 129 at a position outside the charged region D is unnecessary, which contributes to the miniaturization of the charger 12. Further, the cleaning member 129 in the second example has a structure that surrounds the entire circumference of the wire 123 and slides on the wire 123 over the entire circumference to clean the entire circumference of the wire 123.

FIG. 4 is a diagram showing a third example of the charger. Here, FIG. 4 (A) is a plan view, and FIG. 4 (B) is a cross-sectional view. Also in FIG. 4, the elements corresponding to the respective elements of the charger shown in FIGS. 2 and 3 are designated by the same reference numerals as those assigned in FIGS. 2 and 3, and the differences will be described. ..

In the charger 12 shown in FIG. 4, similarly to the first example shown in FIG. 2, the outward path portion and the return path portion of the wire 123 are parallel to each other, and the distance to the image holder 11 is equidistant from each other. , Are arranged horizontally. As a result, the charging performance equivalent to that of a charger equipped with two fixed wires is ensured.

Further, in the case of the third example shown in FIG. 4, the cleaning member 129 is arranged between the wire 123 and the grid 122, is in contact with both the outward path portion and the return path portion of the wire 11, and is also on the grid 122. I'm in contact. The cleaning member 129 is usually arranged at a home position outside the charged region D in the tensioning direction (arrows K1-K2 direction), and is responsible for cleaning the wire 123.

Further, the charger 12 is provided with two guide rods 1291 that penetrate the cleaning member 129 and extend in the stretching direction (arrows K1-K2 direction). One of the two guide rods 1291, the guide rod 1291a, is a simple round rod-shaped rod, but the other guide rod 1291b is formed with a male screw and penetrates the cleaning member 129. It meshes with the female screw formed in the hole and acts as a member for moving the cleaning member 129 in the tensioning direction (arrows K1-K2 direction). The rotational driving force of the motor 101 is switched by a switching mechanism 103 including gears or the like to rotate the drive roll 124 or the guide rod 1291b on which the male screw is formed. When the charger 12 is performing the charging operation, the switching mechanism 103 places the cleaning member 129 at a home position outside the charged region D and rotates the drive roll 124. Then, when the scene of cleaning the grid 122 arrives while the charging operation is stopped, the switching mechanism 103 switches the transmission path of the rotational driving force so that the rotational driving force of the motor 101 is transmitted to the guide rod 1291b. Then, this time, the guide rod 1291b rotates, the cleaning member 129 moves in the tension direction, and the grid 122 is cleaned. It is necessary to reciprocate the cleaning member 129 to return it to the original home position, but the movement direction of the cleaning member 139 is switched by the forward / reverse rotation of the motor 101, or in the case of the motor 101 whose rotation direction is one direction. This is performed by switching the rotation direction by switching the gear or the like in the switching mechanism 103.

Here, an example in which the present invention is applied to the image forming apparatus 100 for forming an image on continuous paper P shown in FIG. 1 has been described, but the present invention is used for an image forming apparatus for forming an image on cut paper. Can be applied as it is.

Further, although an example in which the present invention is applied to an image forming apparatus for forming a color image has been described here, the present invention can be directly applied to an image forming apparatus for forming a monochrome image.

11,11Y, 11M, 11C, 11K Image holder 12, 12Y, 12M, 12C, 12K Charger 13Y, 13M, 13C, 13K Developer 14 Exposure device 21 Intermediate transfer belt 23Y, 23M, 23C, 23K Primary transfer roll 24 Secondary transfer roll 30 Fuser 101 Motor 102 Power supply 103 Switching mechanism 122 Grid 123 Wire 124 Drive roll 125 Tension roll 126 Drive gear 127 Bearing 128 Tension applying member 129 Cleaning member 1211 Cover member 1291, 1291a, 1291b Guide rod

Claims (4)

A wire that is stretched and charges the object to be charged by electric discharge,
A wire moving mechanism that moves the wire in the tension direction,
A grid arranged between the wire and the charged body to control the charge amount of the charged body, and
A portion that is arranged between the wire and the grid, is in contact with both the wire and the grid, is movable in the tensioning direction, and is responsible for charging the charged region and the wire in the charged body. A cleaning member that moves to a position away from the wire and slides in contact with the wire to clean the wire, and also cleans the grid by moving in the tension direction.
Charging characterized by having an application means for applying a voltage to charge the wire to be charged while the wire is moved by the wire moving mechanism and the wire is cleaned by the cleaning member. apparatus. The wire has a ring shape
The charging device according to claim 1, wherein the wire moving mechanism circulates and moves the wire. The charging device according to claim 2, wherein the outward path portion and the return path portion of the cyclically moving wire are arranged in a posture in which the distances from the charged body are equidistant from each other. An image-holding member that holds a toner image through the processes of charging, exposure, and development while rotating, and transfers the toner image onto a transfer target.
The charging device according to any one of claims 1 to 3, wherein the image-holding member is the charged body.
A transport device that transports paper and
A transfer device that transfers the toner image formed on the image-holding member onto the conveyed paper, and
An image forming apparatus including a fixing device for fixing a toner image transferred onto the paper onto the paper.

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