JP5026180B2 - Liquid developing device and image forming apparatus - Google Patents

Description

  The present invention relates to a liquid developing device and an image forming apparatus.

  Among electrophotographic image forming apparatuses, there is a so-called wet image forming apparatus that performs development using a liquid developer. The wet image forming apparatus mainly includes a photosensitive drum on which an electrostatic latent image is formed, a liquid developing device that develops the electrostatic latent image on the surface of the photosensitive drum as a toner image, and the like. The liquid developing device also includes a developing roller for supplying the liquid developer to the surface of the photosensitive drum, a supply roller for supplying the liquid developer to the developing roller, and an appropriate amount of liquid developer supplied to the developing roller. As shown, a doctor blade or the like provided in contact with the surface of the supply roller is included.

  By the way, as a supply roller, for example, an anix roller or the like, a roller whose surface is engraved with a precise cell is often used. A liquid developer is carried on the cell of such a supply roller. The liquid developer carried on the cell is transported to the developing roller after the amount thereof is adjusted by the doctor blade.

As a technique related to this type of liquid developing device, foreign matters such as dust and paper powder mixed in the liquid developer are removed so that the foreign matters mixed in the liquid developer are brought into contact with the supply roller and the doctor blade. There is known a technique for preventing a part from being sent to a part (Patent Document 1).
JP 2002-72695 A

  By the way, in the process of supplying the liquid developer to the developing roller by the supply roller, the liquid developer carried on the cell on the surface of the supply roller is not all supplied to the developing roller, but a part of the liquid developer remains in the cell. There is a case. In general, since the liquid developer contains a solid component made of, for example, a resin or a pigment, the solid component in the liquid developer remaining in the cell of the supply roller is fixed to the bottom of the cell. There is a risk of clogging. Then, the cell of the supply roller becomes shallow, and a necessary amount of developer is not carried on the cell, so that it becomes difficult to supply the necessary amount of liquid developer to the developing roller.

  SUMMARY An advantage of some aspects of the invention is that it provides a liquid developing device capable of suppressing the liquid developer from adhering to the bottom of a cell on the surface of a supply roller, and an image forming apparatus including the liquid developing device.

  The liquid developing device according to the first aspect includes a developing roller, a first supply roller, and a second supply roller. The developing roller carries a liquid developer. The first supply roller has a plurality of recesses on the surface, and supplies the liquid developer to the developing roller. The second supply roller is provided on a peripheral surface of the second supply roller main body disposed opposite to the first supply roller and the second supply roller main body, and a plurality of tip portions can contact the concave portions of the first supply roller. The liquid developer is supplied to the first supply roller.

  According to this liquid developing device, when the second supply roller rotates, the liquid developer carried between the plurality of wires of the second supply roller is supplied to the first supply roller. When the liquid developer is supplied to the first supply roller in this way, the plurality of wire rods come into contact with the recesses on the surface of the first supply roller, so that the toner in the liquid developer remaining in the recesses of the first supply roller is Then, it is peeled off from the bottom of the recess by the wire and diffuses into the carrier. As a result, it is possible to prevent the toner in the liquid developer from adhering to the bottom of the concave portion of the first supply roller and the concave portion of the first supply roller from becoming shallow. Accordingly, a necessary amount of liquid developer is carried in the concave portion, and a necessary amount of liquid developer is supplied to the developing roller, so that deterioration in image quality can be suppressed. Further, according to this liquid developing device, the surface of the first supply roller is cleaned by a plurality of wires, so that the life of the liquid developing device can be extended without providing a separate mechanism for cleaning the surface of the first supply roller. In addition, the space of the liquid developing device itself can be saved. Furthermore, while the second supply roller is rotating, the surface of the first supply roller is cleaned by a plurality of wires, so that it is not necessary to provide a separate cleaning mode for cleaning the surface of the first supply roller. .

  A liquid developing device according to a second aspect of the present invention is the liquid developing device according to the first aspect of the present invention, further comprising a developer storage section in which the liquid developer is stored. The second supply roller pumps up the liquid developer stored in the developer storage unit and supplies the liquid developer to the first supply roller.

  As described above, the liquid developing device of the present invention can be applied as a pumping-type liquid developing device in which the second supply roller pumps up the liquid developer. As a result, when the second supply roller rotates, the liquid developer in the developer reservoir is carried between the plurality of wires of the second supply roller and is eventually supplied to the first supply roller.

  A liquid developing device according to a third aspect is the liquid developing device according to the first aspect, further comprising a developer supply member that supplies the liquid developer to the second supply roller. The second supply roller supplies the liquid developer supplied by the developer supply member to the first supply roller.

  Thus, the liquid developing device of the present invention can be applied as a liquid developing device of a type in which the liquid developer is supplied to the second supply roller by the developer supply member. According to this liquid developing device, when the second supply roller rotates, the liquid developer supplied to the second supply roller by the developer supply member is carried on the plurality of wires of the second supply roller, and eventually the first supply roller. To be supplied. As a result, a more appropriate amount of liquid developer is supplied to the first supply roller.

  A liquid developing device according to a fourth aspect is the liquid developing device according to any one of the first to third aspects, further comprising a cleaning member. The cleaning member is disposed so as to come into contact with the plurality of wires, and the second developer roller rotates to remove the liquid developer from the plurality of wires.

  According to this liquid developing device, since the liquid developer that is not supplied to the first supply roller and remains between the plurality of wires is removed by the cleaning member, the wire developer that scrapes the liquid developer from the concave portion of the first supply roller is removed. Capability reduction can be prevented.

  A liquid developing device according to a fifth aspect is the liquid developing device according to the fourth aspect, wherein the cleaning member is a plate-like member or a columnar member.

  An image forming apparatus according to a sixth aspect includes an image carrier, a liquid developing device, and a transfer device. The liquid developing device includes a developing roller that carries a liquid developer and develops the electrostatic latent image on the image carrier as a toner image, a plurality of concave portions on the surface, and supplies the liquid developer to the developing roller. 1 supply roller and a second supply roller for supplying the liquid developer to the first supply roller. The transfer device transfers the toner image developed by the liquid developing device to a transfer material. The second supply roller is provided on the second supply roller main body disposed opposite to the first supply roller and on the peripheral surface of the second supply roller main body, and the tip portion can contact the concave portion of the first supply roller. A plurality of wire rods.

  According to this image forming apparatus, when the second supply roller rotates, the liquid developer carried between the plurality of wires of the second supply roller is supplied to the first supply roller. When the liquid developer is supplied to the first supply roller in this way, the plurality of wire rods come into contact with the recesses on the surface of the first supply roller, so that the toner in the liquid developer remaining in the recesses of the first supply roller is Then, it is peeled off from the bottom of the recess by the wire and diffuses into the carrier. As a result, it is possible to prevent the toner in the liquid developer from adhering to the bottom of the concave portion of the first supply roller and the concave portion of the first supply roller from becoming shallow. Accordingly, a necessary amount of liquid developer is carried in the concave portion, and a necessary amount of liquid developer is supplied to the developing roller, so that deterioration in image quality can be suppressed. In addition, since the surface of the first supply roller is cleaned by a plurality of wires, the life of the liquid developing device can be extended without providing a separate mechanism for cleaning the surface of the first supply roller. Space-saving of the developing device itself can be achieved. Furthermore, while the second supply roller is rotating, the surface of the first supply roller is cleaned by a plurality of wires, so that it is not necessary to provide a separate cleaning mode for cleaning the surface of the first supply roller. .

  An image forming apparatus according to a seventh aspect is the image forming apparatus according to the sixth aspect, wherein the liquid developing device further includes a developer reservoir that stores the liquid developer. The second supply roller pumps up the liquid developer stored in the developer storage unit and supplies the liquid developer to the first supply roller.

  In this image forming apparatus, as the liquid developing device, a pump-up type liquid developing device in which the second supply roller pumps up the liquid developer can be applied. As a result, when the second supply roller rotates, the liquid developer in the developer reservoir is carried between the plurality of wires of the second supply roller and is eventually supplied to the first supply roller.

  An image forming apparatus according to an eighth aspect of the present invention is the image forming apparatus according to the sixth aspect, wherein the liquid developing device further includes a developer supply member that supplies the liquid developer to the second supply roller. The second supply roller supplies the liquid developer supplied by the developer supply member to the first supply roller.

  In this image forming apparatus, as the liquid developing device, a liquid developing device of a type in which a liquid developer is supplied by a developer supplying member to the second supply roller can be applied. As a result, when the second supply roller rotates, the liquid developer supplied to the second supply roller by the developer supply member is carried by the plurality of wires of the second supply roller and is eventually supplied to the first supply roller. . Accordingly, a more appropriate amount of liquid developer is supplied to the first supply roller.

  An image forming apparatus according to a ninth aspect is the image forming apparatus according to any one of the sixth to eighth aspects, wherein the liquid developing device is disposed so as to contact a plurality of wires, and the second supply roller rotates. A cleaning member for removing the liquid developer from the plurality of wires is further included.

  According to this image forming apparatus, the liquid developer that is not supplied to the first supply roller in the liquid developing device and remains between the plurality of wires is removed by the cleaning member, so that the liquid developer is removed from the recess of the first supply roller. It is possible to prevent a decrease in the ability of the wire rod that scrapes off the wire.

  An image forming apparatus according to a tenth aspect is the image forming apparatus according to the ninth aspect, wherein the cleaning member is a plate-like member or a columnar member.

  According to the liquid developing device and the image forming apparatus of the present invention, it is possible to suppress the toner in the liquid developer from adhering to the bottom of the recess of the supply roller.

  Hereinafter, an embodiment of an image forming apparatus employing a liquid developing device according to the present invention will be described with reference to the drawings.

  In this embodiment, a printer is described as an example of the image forming apparatus. However, the image forming apparatus in which the liquid developing device of the present invention is employed is not limited to this. In other words, the image forming apparatus only needs to include an image forming unit having a liquid developing device and a photosensitive drum, and is a so-called multi-function peripheral (MFP) having a function as a copying machine, a facsimile machine, or a copying function. The present invention can be applied to various devices such as a device equipped only with the above.

(1) Configuration FIG. 1 is a longitudinal sectional view showing a main configuration of the image forming apparatus X1. An image forming apparatus X1 shown in FIG. 1 mainly includes a tandem image forming unit A1 that forms a toner image based on image data received from an external device such as a PC, a paper storage unit 2 that stores paper, and an image forming unit. A secondary transfer unit 3 that transfers the toner image formed in A1 onto the paper, a fixing unit 4 that fixes the transferred toner image on the paper, and a discharge device that discharges the paper on which the toner image is fixed to the outside of the image forming apparatus X1. 5 and a paper discharge tray 7 for receiving the discharged paper. The image forming apparatus X1 further includes a paper transport unit 6 that transports paper from the paper storage unit 2 to the discharge device 5.

  The image forming unit A1 includes an intermediate transfer belt B1, a cleaning unit B2 for the intermediate transfer belt B1, and an image forming unit FY corresponding to each color of yellow (Y), magenta (M), cyan (C), and black (Bk). , FM, FC, FB.

  The intermediate transfer belt B1 is an endless (that is, looped) belt-like member having conductivity, and is circulated and driven clockwise in FIG. Hereinafter, the surface of the intermediate transfer belt B1 facing outward in circulation driving may be referred to as a front surface, and the surface of the other intermediate transfer belt B1 may be referred to as a back surface.

  The image forming units FY, FM, FC, and FB are arranged along the intermediate transfer belt B1 downstream of the cleaning unit B2 of the intermediate transfer belt B1 and upstream of the secondary transfer unit 3 in the moving direction of the intermediate transfer belt B1. Arranged in order. Note that the order of arrangement of the image forming units FY, FM, FC, and FB is not limited to this, but this arrangement is preferable in consideration of the influence of the color mixture on the completed image.

[Image forming unit]
Since the image forming units FY, FM, FC, and FB have substantially the same configuration, the image forming unit FY will be described below as an example.

  As shown in FIG. 2, the image forming unit FY includes a photosensitive drum 10, a charger 11, an LED exposure device 12, a yellow liquid developing device HY, a primary transfer roller 20, a cleaning blade 31 a for the photosensitive drum 10, and static elimination. The apparatus 13 and the carrier removal roller 30 are provided.

  The image forming units FM, FC, and FB other than the image forming apparatus unit FY include liquid developing devices HM, HC, and HB corresponding to the respective colors as shown in FIG. Further, among the image forming units, the image forming unit FB located on the most downstream side in the moving direction of the intermediate transfer belt B1 is not provided with the carrier removing roller 30 because the image forming unit is not located downstream thereof. Other configurations are the same.

  The photosensitive drum 10 is a substantially columnar member that is arranged to be rotatable in the direction of an arrow A in FIG. 2 about a rotation axis perpendicular to the moving direction of the intermediate transfer belt B1. The photosensitive drum 10 can carry a toner image including toner charged on its surface (in this embodiment, charged positively). Around the photosensitive drum 10, a cleaning blade 31a, a charge eliminating device 13, a charger 11, an LED exposure device 12, and a yellow liquid developing device HY are arranged in this order.

  The charger 11 uniformly charges the surface of the photosensitive drum 10 by, for example, corona discharge.

  The LED exposure device 12 has an LED light source. The LED exposure device 12 irradiates the charged photosensitive drum 10 surface with light based on the image data received by the image forming apparatus X1 from an external device such as a PC, and forms an electrostatic latent image on the photosensitive drum 10 surface. To do.

  The yellow liquid developing device HY holds a liquid developer containing yellow toner and a liquid carrier (hereinafter sometimes simply referred to as a developer) so as to face the electrostatic latent image. Toner is applied to the electrostatic latent image, and the electrostatic latent image is developed as a toner image. This toner image is primarily transferred to the intermediate transfer belt B1 by the primary transfer roller 20. The detailed configuration of the liquid developing device will be described later.

  The cleaning blade 31 a is a blade-like member disposed so as to be in contact with the surface of the photosensitive drum 10. The cleaning blade 31a removes the developer remaining on the surface of the photosensitive drum 10 after the primary transfer.

  The neutralization device 13 includes a light source. After the developer is removed by the cleaning blade 31a, the surface of the photosensitive drum 10 is neutralized by light from the light source to prepare for the next image formation.

  The primary transfer roller 20 is disposed in contact with the back surface of the intermediate transfer belt B1. The primary transfer roller 20 is applied with a voltage having a polarity (minus in this embodiment) opposite to the charging polarity of the toner in the toner image from a power source (not shown). Since the intermediate transfer belt B1 has electrical conductivity, the toner is attracted to the surface side of the intermediate transfer belt B1 and its periphery by applying the voltage to the primary transfer roller 20.

  During the primary transfer, a small amount of carrier may be transferred from the photosensitive drum 10 to the intermediate transfer belt B1 together with the toner. Such carrier transfer may prevent primary transfer in the downstream image forming unit and cause image defects such as image blurring and blurring. Therefore, the carrier removal roller 30 is provided as a member for removing the carrier from the photosensitive drum 10. As a result, the carrier on the photosensitive drum 10 is removed, and the above-described image defects can be prevented.

  Here, in this embodiment, the carrier removal roller 30 is incorporated in the cleaning unit 31 together with the cleaning blade 31a. The cleaning unit 31 is provided in the image forming unit FY, and further includes a carrier removing blade 31b and a conveying member 31c in addition to the cleaning blade 31a and the carrier removing roller 30. The carrier removal blade 31b is in contact with the surface of the carrier removal roller 30 to remove the carrier liquid adhering to the surface of the carrier removal roller 30. The conveyance member 31 c conveys the carrier removed from the carrier removal roller 30 and the developer (including toner and carrier) removed from the surface of the photosensitive drum 10 by the cleaning blade 31 a to the outside of the cleaning unit 31. The image forming unit FY may further include a separation unit (not shown) that separates the carrier and the toner in order to reuse the carrier and the toner conveyed by the conveyance member 31c.

[Liquid developing device]
Next, the configuration of the liquid developing apparatus according to this embodiment will be described. Since the liquid developing devices HY, HM, HC, and HB have the same configuration, the configuration of the liquid developing device HY will be described below as an example.

  As shown in FIG. 2, the liquid developing device HY mainly includes a developing container (corresponding to a developer storage unit) 40, a developing roller 41, a supply roller 42 (corresponding to a first supply roller), and a pumping roller 43 (second supply). A stirring roller 44a, 44b, a developing cleaning blade 45, a supply roller doctor blade 46, a wire cleaning member 47 (corresponding to a cleaning member), a toner concentration sensor 48, and a liquid level sensor 49.

  Developer is stored in the developing container 40.

  The developing roller 41 is disposed so as to face the photosensitive drum 10 and be in contact with the photosensitive drum 10, and carries a developer. The developing roller 41 rotates in the direction of arrow B in FIG. 2, thereby supplying the carried developer to the photosensitive drum 10. More specifically, when the developing roller 41 contacts the photosensitive drum 10, a potential difference is generated between the potential of the electrostatic latent image on the surface of the photosensitive drum 10 and the developing bias applied to the developing roller 41. Due to this potential difference, a toner image based on the image data is formed on the surface of the photosensitive drum 10 (development operation).

  The supply roller 42 is disposed to face the developing roller 41 and has a plurality of concave portions (hereinafter referred to as cells) on the surface. The supply roller 42 supplies developer to the developing roller 41 by rotating in the direction of arrow C in FIG. Examples of the type of the supply roller 42 include an anix roller, a blast roller, and a wire roller. In the present embodiment, the case where the supply roller 42 is an anix roller is taken as an example.

The scooping roller 43 is arranged so that at least a part thereof is immersed in the developer in the developing container 40, and can rotate in the direction of arrow D in FIG. In particular, as shown in FIG. 3, the pumping roller 43 according to the present embodiment has a pumping roller main body 43a and a plurality of wire rods 43b, and pumps up the developer stored in the developing container 40 to supply roller 42. To supply. The pumping roller main body 43a is disposed so as to face the supply roller 42, and the plurality of wire rods 43b are provided on the peripheral surface of the pumping roller main body 43a, and the tip portion extends so as to be in contact with the cells of the supply roller 42. More specifically, the plurality of wires 43b have such a length that the front end portion is sufficiently in contact with the surface of the supply roller 42 so that the front end portion can contact the bottom portion of the cell of the supply roller 42. It is good to have. For example, when the depth of the cell is about 45 μm, each wire 43 b has a length of, for example, about 5 mm so that a portion of about 1 mm from the tip portion contacts the surface of the supply roller 42. Further, the plurality of wire rods 43b are formed of resin fibers that are somewhat rigid, such as nylon, or fibers made of a metal material such as stainless steel. In this embodiment, as a plurality of wires, a non-conductive brush made of 6.6 nylon manufactured by Toray Industries, Inc. (volume resistance: 4.8 × 10 ¹² Ω · cm, average diameter of one wire: 6 Denier (here, a bundle of 35 wire rods is planted as a unit. The thickness of the bundle is 210 denier, and the density of hair transplantation: 37000 / inch ² ) can be used.

  According to the pumping roller 43 having such a configuration, the developer in the developing container 40 is carried between the wire rods 43b. When the scooping roller 43 rotates in the direction of arrow D in this state, the developer carried between the wires 43 b is supplied to the supply roller 42. At this time, the tip portions of the plurality of wire rods 43b come into contact with the bottom of the cell on the surface of the supply roller 42, so the toner adhering to the bottom of the cell or the toner adhering to the cell is peeled off from the bottom of the cell, Diffused into the carrier.

  The agitation spirals 44a and 44b are provided so as to be entirely immersed in the developer in the developing container 40, and agitate the developer. As each stirring spiral 44a, 44b rotates, the toner particles are uniformly dispersed in the carrier.

  The development cleaning blade 45 is disposed so as to be in contact with the surface of the development roller 41 and removes the developer remaining on the development roller 41 that is not used for developing the electrostatic latent image on the photosensitive drum 10. The developer on the developing roller 41 removed by the developing cleaning blade 45 flows down along the surface of the developing cleaning blade 45 and is stored in a developer tank (not shown) through a flow path (not shown). Mixed with the developer.

  The supply roller doctor blade 46 is disposed so as to be in contact with the surface of the supply roller 42 and regulates the developer layer thickness on the surface of the supply roller 42 to a predetermined thickness. Thereby, the layer thickness of the developer formed on the surface of the developing roller 41 is also maintained at a predetermined thickness.

  The wire cleaning member 47 is disposed so as to be in contact with the plurality of wire rods 43b of the drawing roller 43, and is configured by a plate-like member. The wire cleaning member 47 removes the developer from the wire 43b by scraping the developer remaining between the plurality of wires 43b without being supplied to the supply roller 42 when the pumping roller 43 rotates.

  The toner concentration sensor 48 detects the toner concentration in the developing container 40. The toner density detected by the toner density sensor 48 is used when the toner density in the developing container 40 is controlled to be a predetermined value.

  The liquid level sensor 49 is provided in the developing container 40 and detects whether or not the liquid level S of the developer in the developing container 40 is a predetermined value. When the liquid level sensor 49 detects that the developer level S is lower than a predetermined value, the developer in the developer tank (not shown) until the developer level S reaches a predetermined position. Is supplied to the developing container 40.

(2) Operation Next, the image forming operation of the image forming apparatus X1 and the operation inside the liquid developing device will be described.

  First, upon receiving an image formation start instruction and image data from an external device such as a PC, the image forming apparatus X1 forms toner images of each color based on the image data using the image forming units FY, FM, FC, and FB. To do. The toner image formed in this way is transferred to the intermediate transfer belt B1, and is superimposed on the intermediate transfer belt B1 to form a color toner image. In synchronization with the formation of the color toner image, the sheets stored in the sheet storage unit 2 are taken out one by one by a paper feeding device (not shown) and conveyed onto the sheet conveyance unit 6. Then, the sheet conveyed to the sheet conveying unit 6 is sent to the secondary transfer unit 3 in synchronization with the primary transfer to the intermediate transfer belt B1. The color toner image on the intermediate transfer belt B <b> 1 is secondarily transferred to the sheet sent to the secondary transfer unit 3.

  Next, the sheet on which the color toner image has been transferred is further conveyed to the fixing unit 4 and fixed on the sheet by heat and pressure. Thereafter, the paper is further discharged onto the paper discharge tray 7 by the discharge device 5. The toner remaining on the intermediate transfer belt B1 after the secondary transfer is removed from the intermediate transfer belt B1 by the cleaning unit B2 of the intermediate transfer belt B1.

  Along with such an image forming operation, in each of the liquid developing devices HB, HC, HM, and HY, the rollers 41, 42, and 43 and the stirring spirals 44a and 44b rotate, and the above-described developing operation is performed. In this developing operation, the plurality of wire rods 43b of the pumping roller 43 supplies the developer in the developing container 40 to the supply roller 42 and also contacts the surface of the supply roller 42, so that the bottom of the cell on the surface of the supply roller 42 is reached. The toner to be fixed or the toner to be fixed is peeled off from the bottom of the cell.

  The plurality of wire rods 43 b after coming into contact with the surface of the supply roller 42 come into contact with the wire rod cleaning member 47. By this wire rod cleaning member 47, the developer remaining between the wire rods 43b is removed.

(3) Effect (A)
The pumping roller 43 according to the liquid developing devices HY, HM, HC, and HB of the present embodiment includes a pumping roller main body 43a and a plurality of wire rods 43b provided on the peripheral surface of the pumping roller main body 43a. When the pumping roller 43 rotates, the developer in the developing container 40 is carried between the plurality of wire rods 43 b of the pumping roller 43 and is supplied to the supply roller 42 before long. When the developer is supplied to the supply roller 42 in this way, the plurality of wire rods 43b come into contact with the cells on the surface of the supply roller 42. Therefore, the toner in the developer remaining in the cells of the supply roller 42 is caused by the wire rod 43b. It is peeled off from the bottom of the cell and diffuses into the carrier. As a result, it is possible to prevent the toner in the developer from adhering to the bottom of the cell of the supply roller 42 and making the cell of the supply roller 42 shallow. Therefore, since a required amount of developer is carried on the cell and a necessary amount of developer is supplied to the developing roller 41, it is possible to suppress a decrease in image quality. Further, according to the liquid developing devices HY, HM, HC, and HB, the surface of the supply roller 42 is cleaned by the plurality of wire rods 43b, so that the liquid development can be performed without providing a separate mechanism for cleaning the surface of the supply roller 42. The lifetimes of the devices HY, HM, HC, and HB can be extended, and the space for the liquid developing device itself can be saved. Further, while the pumping roller 43 is rotating, the surface of the supply roller 42 is cleaned by the plurality of wire rods 43b, so that it is not necessary to provide a separate cleaning mode for cleaning the surface of the supply roller.

(B)
Further, according to the liquid developing devices HY, HM, HC, and HB of the present embodiment, the developer that is not supplied to the supply roller 42 and remains between the plurality of wires 43b is removed by the wire cleaning member 47. It is possible to prevent a reduction in the capability of the wire 43b that scrapes the developer from the cell on the surface of the supply roller 42.

<Other embodiments>
(A)
In the above-described embodiment, as shown in FIG. 2, the liquid developing devices HY, HM, HC, HB including the pumping roller 43 that is at least partially immersed in the developer, and the image forming apparatus X1 using the same. explained. However, the present invention can be applied to the liquid developing devices HY ′, HM ′, HC ′, and HB ′ as shown in FIGS. 4 and 5 and the image forming apparatus X101 including the same.

  As shown in FIG. 4, the image forming apparatus X101 according to the present embodiment includes image forming units FY ′, FM ′, FC ′, and FB ′ instead of the image forming units FY, FM, FC, and FB of FIG. ing. The configuration other than the image forming units FY ′, FM ′, FC ′, and FB ′ has the same configuration as that of the image forming apparatus X1 of FIG. 1 according to the above embodiment. Further, the image forming units FY ′, FM ′, FC ′, FB ′ have liquid developing devices HY ′, HM ′, HC ′, HB ′ instead of the liquid developing devices HY, HM, HC, HB of FIG. is doing. Note that members already mentioned as the configuration of the image forming apparatus X1, in particular, the image forming units FY, FM, FC, and FB, are given the same reference numerals and description thereof is omitted. In addition, since the liquid developing devices HY ′, HM ′, HC ′, and HB ′ have the same configuration as in the above embodiment, the configuration of the liquid developing device HY ′ will be described below as an example.

  As shown in FIG. 5, the liquid developing device HY ′ mainly includes a developing roller 141, a supply roller 142 (corresponding to a first supply roller), a support roller 143 (corresponding to a second supply roller), a developer supply member 144, A developer removing device 145, a developer charging device 146, a supply roller doctor blade 147, and a wire cleaning member 148 (corresponding to a cleaning member) are provided.

  As in the above embodiment, the developing roller 141 is disposed so as to be in contact with the photosensitive drum 10 and carries a developer. Similarly to the above embodiment, the supply roller 142 is disposed to face the developing roller 141, has a plurality of concave portions (that is, cells) on the surface, and supplies the developer to the developing roller 141. The support roller 143 is a member for supporting the developer together with the supply roller 142, and supplies the developer to the supply roller 142. In particular, the support roller 143 is provided on a support roller main body 143 a disposed to face the supply roller 142, and a peripheral surface of the support roller main body 143 a, and a plurality of end portions extend so as to be in contact with the cells of the supply roller 142. Wire 143b.

  The developer supply member 144 is a member for supplying the developer to the support roller 143 near the contact portion between the supply roller 142 and the support roller 143. The developer supply member 144 is connected to a developer circulation device (not shown) that circulates the developer in order to reuse the developer that has not been used for image formation. The developer removing device 145 is a device for removing developer remaining on the developing roller 141 without being supplied to the photosensitive drum 10, and a developer cleaning blade for scraping off the developer from the developing roller 141. Etc. The developer charging device 146 is a device for charging the toner in the developer carried on the developing roller 141, and is disposed in the vicinity of the developing roller 141. The supply roller doctor blade 147 is disposed so as to be in contact with the surface of the supply roller 142 and regulates the developer layer thickness on the surface of the supply roller 142 to a predetermined thickness. The wire cleaning member 148 is disposed so as to be in contact with the plurality of wires 143b of the support roller 143, and is configured by a plate-like member.

  According to the liquid developing device HY ′ having such a configuration, when the support roller 143 rotates, the developer supplied to the support roller 143 by the developer supply member 144 is carried on the plurality of wires 143b of the support roller 143, Eventually, the toner is supplied to the supply roller 142. As a result, a more appropriate amount of liquid developer is supplied to the supply roller 142. When the developer is supplied to the supply roller 142, the plurality of wires 143b come into contact with the cells on the surface of the supply roller 142. Therefore, the toner in the developer remaining in the cells is peeled off from the bottom of the cells by the wires 143b. And diffuse into the carrier. Further, when the support roller 143 rotates, the developer remaining between the plurality of wires 143 b without being supplied to the supply roller 142 is scraped off by the wire cleaning member 148. Thereby, there can exist an effect similar to the said embodiment.

(B)
In the above embodiment and the other embodiment (a), as shown in FIGS. 2 and 5, the case where the wire cleaning members 47 and 148 are formed of plate-like members has been described as an example. However, the wire cleaning member is not limited to a plate-like member. That is, the wire member cleaning member only needs to have a structure capable of removing the developer from the plurality of wire members 43b and 143b. For example, as shown in FIG. 6 and FIG. Cleaning members 47 ′ and 148 ′ for wire rods of FIGS. 6 and 7). FIG. 6 is a vertical cross-sectional view showing the configuration of the main part of the image forming unit FY in the image forming apparatus X1 according to the above embodiment, and shows the case where the wire member cleaning member is a columnar member. is there. FIG. 7 is a longitudinal cross-sectional view showing the main configuration of the image forming unit FY ′ in the image forming apparatus X101 according to another embodiment (a), and shows a case where the wire material cleaning member is a roller. It is. As a result, as in the above embodiment, it is possible to prevent the ability of the wire rods 43b and 143b from scraping the developer from the cells on the surfaces of the supply rollers 42 and 142 from being reduced.

FIG. 2 is a longitudinal sectional view showing the main configuration of an image forming apparatus X1 according to an embodiment of the present invention. FIG. 3 is a longitudinal sectional view showing a main configuration of an image forming unit FY in the image forming apparatus X1. FIG. 3 is an enlarged view of a part of the liquid developing device HY in FIG. 2. FIG. 6 is a longitudinal sectional view showing a main configuration of an image forming apparatus X101 according to another embodiment (a). FIG. 3 is a longitudinal sectional view showing the main configuration of an image forming unit FY ′ in the image forming apparatus X101. FIG. 6 is a longitudinal sectional view showing a main configuration of an image forming unit FY in an image forming apparatus X1 according to another embodiment (b). FIG. 10 is a longitudinal sectional view showing a main configuration of an image forming unit FY ′ in an image forming apparatus X101 according to another embodiment (b).

Explanation of symbols

X1, X101 Image forming apparatus A1 Image forming portions HY, HM, HC, HB, HY ′, HM ′, HC ′, HB ′ Liquid developing device B1 Intermediate transfer belt 3 Secondary transfer portion 10 Photosensitive drum 40 Developing container 41, 141 Developing roller 42, 142 Supply roller 43 Pumping roller 143 Support roller 43a Pumping roller main body 143a Support roller main body 43b, 143b Wire rods 47, 148 Wire rod cleaning member 144 Developer supply member

Claims (6)

A developing roller carrying a liquid developer;
A first supply roller having a plurality of recesses on a surface and supplying the liquid developer to the development roller;
A second supply roller body disposed opposite to the first supply roller; and a plurality of wires provided on a peripheral surface of the second supply roller body, the tip portion of which can contact the recess of the first supply roller A second supply roller that supplies the liquid developer to the first supply roller;
A developer supplying member that supplies the liquid developer to the vicinity of the contact portion between the first supply roller and the second supply roller and upstream of the contact portion in the rotation direction of the second supply roller; Prepared,
The second supply roller supplies the liquid developer supplied by the developer supply member to the first supply roller;
Liquid developing device. A cleaning member that is disposed so as to contact the plurality of wires, and that removes the liquid developer from the plurality of wires by rotation of the second supply roller;
The liquid developing device according to claim 1 . The cleaning member is a plate member or a columnar member.
The liquid developing device according to claim 2 . An image carrier;
A developing roller that carries a liquid developer and develops the electrostatic latent image on the image carrier as a toner image, and a first supply that has a plurality of recesses on the surface and supplies the liquid developer to the developing roller A liquid developing device including a roller, a second supply roller that supplies the liquid developer to the first supply roller, and a developer supply member that supplies the liquid developer to the second supply roller;
A transfer device for transferring the toner image developed by the liquid developing device to a transfer material;
With
The second supply roller is provided on a second supply roller main body disposed opposite to the first supply roller, and on a peripheral surface of the second supply roller main body, and a tip portion is the concave portion of the first supply roller. A plurality of wires that can come into contact with
The developer supply member supplies the liquid developer near the contact portion between the first supply roller and the second supply roller and upstream of the contact portion in the rotation direction of the second supply roller. ,
The second supply roller supplies the liquid developer supplied by the developer supply member to the first supply roller;
Image forming apparatus. The liquid developing device further includes a cleaning member that is disposed so as to contact the plurality of wires, and that removes the liquid developer from the plurality of wires as the second supply roller rotates.
The image forming apparatus according to claim 4 . The cleaning member is a plate member or a columnar member.
The image forming apparatus according to claim 5 .

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