JP2006010768A - Cartridge and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a brush used to apply voltage to the photoreceptor of an electrophotographic image forming apparatus, which is constituted to prevent the rise of manufacture cost and adverse influence exerted on the photoreceptor and satisfactorily apply the voltage to the photoreceptor. <P>SOLUTION: Ground fabric 72 is formed of an insulating fiber, and brush bristles 71 are flocked in a state where they are erected on a holding surface being the either side surface of the ground fabric 72, and the ground fabric 72 is equipped with a back coat layer 73 formed by being impregnated with conductive fluid on a non-holding surface on an opposite side to the holding surface. An electrode 75 feeds power to the brush 54 by coming into contact with the back coat layer 73 in the non-flocked area of the ground fabric 72. Therefore, a situation that the conductive fluid goes along the brush bristles 71 and adheres to the photoreceptor drum 27 is prevented by such a printer 1, so that the adverse influence is prevented from being exerted on image forming. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cartridge having a brush for applying a voltage to the surface of a photoreceptor and an image forming apparatus.

Conventionally, as a means for applying a voltage to a photoreceptor of an electrophotographic image forming apparatus, one using a brush is known (for example, see Patent Document 1).
This brush is formed by implanting a large number of conductive bristles on an insulating cloth (base cloth), and the tips of the bristles are arranged in contact with the photoreceptor. Moreover, in order to ensure the electroconductivity of a base fabric, this base fabric is impregnated with the electroconductive backcoat agent in the state where the brush hair was planted.

And this brush is applied to the brush hair through the back coat agent by applying an electrode to the portion where the brush hair is not implanted on the surface (surface) of the base fabric where the brush hair is implanted. A voltage is applied.
Japanese Patent No. 3191027

  By the way, since the brush is configured so that the electrode can be applied from the surface of the base fabric, assuming that the back coat agent is impregnated from the surface (back surface) on which the brush hair of the base fabric is not woven, It is necessary to sufficiently impregnate the backcoat agent until the backcoat agent exudes from the surface of the base fabric.

  However, if the base fabric is impregnated with a large amount of backcoat agent, the backcoat agent adheres to the brush hair due to capillary action, and if the backcoat agent attached to the brush hair adheres to the photoconductor, it adversely affects image formation. There was a problem.

  That is, when the backcoat agent adheres to the brush hair, the photoconductor is contaminated by the backcoat agent, or current leaks to the surface of the photoconductor, so that a uniform image cannot be formed.

  In order to solve this problem, for example, a configuration in which a conductive base fabric is used and no backcoat agent is used can be considered. However, in this case, since the conductive base fabric is generally expensive, there arises a problem that the manufacturing cost of the brush becomes high.

  It is also conceivable to attach a brush to a conductive member such as a metal plate using a conductive adhesive, and to apply a voltage to the brush bristles through this conductive member. Since the adhesive strength is generally weaker than that of a conductive adhesive, the use of a conductive adhesive makes it easy for the brush to be peeled off, and the photoconductor and the brush may not be in good contact.

  Therefore, in view of such problems, in the brush used for applying a voltage to the photoreceptor of the electrophotographic image forming apparatus, the manufacturing cost of the brush is increased, and the photoreceptor is adversely affected. It is an object of the present invention to prevent voltage and to make it possible to satisfactorily apply a voltage to the photoreceptor.

  In order to achieve the above object, the invention according to claim 1 is characterized in that an electrostatic latent image is formed on the surface of a photoreceptor, the electrostatic latent image is developed with a developer, and an image is formed on a recording medium. A cartridge that can be detachably attached to the image forming apparatus for forming the image forming apparatus, wherein a plurality of brush hairs are implanted in the holding body, contact the surface of the photoconductor, and apply a voltage to the surface of the photoconductor. And a power supply means for receiving a power supply from an external power source and applying a voltage to the brush, wherein the brush holder is made of a cloth formed of insulating fibers, and one of the cloths The bristle is planted so that the bristle is in an upright state on the holding surface, which is the side surface, and a conductive layer that contacts the bristle is on the non-holding surface opposite to the holding surface. Comprising the formed conductive portion, the power supply means, By contact with the conductive portion of the bearing member, it is characterized in that power the brush.

  Therefore, according to such a cartridge, since the conductive portion is formed on the non-holding surface side, it is possible to prevent the material forming the conductive portion from being transmitted along the bristles and adhering to the photoconductor. For this reason, it is possible to prevent adverse effects on image formation.

In addition, since the power supply means can apply a voltage to the brush bristles well, the voltage can also be applied to the photoreceptor.
By the way, the conductive part may be formed by impregnating a conductive fluid, as specifically described in claim 2.

That is, in the holding body in which the bristles are implanted, the conductive fluid is impregnated so as not to reach the holding surface side from the non-holding surface side.
Therefore, according to such a cartridge, it is possible to prevent the conductive fluid from passing through the bristles and sticking to the photosensitive member. When it has a non-flocked area | region which has not been carried out, it is preferable to supply electric power to a brush by a power supply means contacting the electrically-conductive part in the non-flocked area | region of a holding body as described in Claim 3.

According to such a cartridge, since the brush hair does not get in the way when the power supply means is arranged, the power supply means can be easily arranged.
Next, in the cartridge according to claim 1 or 2, the power supply means includes an electrode, and when the electrode is brought into contact with the holding body from the holding surface side, the electrode and the conductive portion of the holding body are electrically connected. Need to connect to.

  For this purpose, for example, as described in claim 4, a conductive fiber woven into the non-planted region of the holding body and capable of conducting electricity with the conductive portion of the holding body is provided, and the electrode is in contact with the conductive fiber. It may be configured, and as described in claim 5, the holding surface side of the non-planted region of the holding body is provided with a current-carrying part formed by impregnating and solidifying a conductive fluid, and the electrode is a current-carrying part You may comprise so that it may contact. Alternatively, as described in claim 6, the electrode is penetrated from the holding surface side in the non-flocked region of the holding body toward the non-holding surface side opposite to the holding surface, whereby the conductive portion of the holding body. In the case where the non-planted region of the holding body is located at the end of the holding body, as described in claim 7, the electrode is formed in the non-flocked region of the holding body. The non-holding surface opposite to the holding surface may be configured to be in contact with the folded non-holding surface in a state where the non-holding surface is folded back to the holding surface side.

According to such a cartridge, conduction between the electrode and the conductive portion of the holding body can be secured without adversely affecting the bristle by the conductive fluid.
In particular, according to the cartridge of the fourth aspect, the amount of generally expensive conductive fibers can be made very small. For this reason, it is possible to prevent an increase in cost while ensuring conduction between the electrode and the conducting portion of the holding body.

Further, in the cartridge according to claim 1 or 2, the power supply means may include an electrode that directly contacts at least a part of the bristle as described in claim 8.
According to such a cartridge, even when the electrode is in contact with the holding body from the holding surface side, a voltage can be applied to the brush hair without providing a member that conducts the electrode and the conducting portion of the holding body. it can.

  Furthermore, in the cartridge according to any one of claims 1 to 8, as described in claim 9, a holding member that supports a non-holding surface side opposite to the holding surface of the holding body, and a holding member It is desirable to include a bonding material that is disposed between the body and the support member and bonds the holding body and the support member.

According to such a cartridge, since the holding body is fixedly supported on the non-holding surface side, the entire brush bristles can be brought into good contact with the photoreceptor.
Further, in the cartridge according to claim 1 or 2, as described in claim 10, the cartridge includes a support member and a bonding material, and the bonding material is laminated so as to contact the entire non-holding surface of the holding body. You may comprise so that it may be made to contact a support member in the state made.

  According to such a cartridge, since the joining material is laminated on the holding body in advance, both of them can be joined simply by contacting the support member, so that the assembly of the cartridge equipped with this brush can be facilitated. Can do.

  Next, in the cartridge according to claim 10, when the power supply means includes an electrode, as described above, the electrode may be contacted from the holding surface side of the holding body, but the electrode is held. You may arrange | position between a body and a supporting member, and may make an electrode and a non-holding surface (conduction part) contact directly.

  That is, as described in claim 11, the bonding material is formed with a notch portion that is notched so that a part of the non-holding surface is exposed on the non-holding surface side of the holding body, What is necessary is just to be arrange | positioned in the position where the notch part of the bonding | jointing material is formed between the non-holding surface and support member of a body, and it should just be comprised so that the non-holding surface of a holding body may be contacted.

  Therefore, according to such a cartridge, even when the holding member and the support member are bonded in a state in which the bonding material is laminated on the holding member in advance, the cutout portion is formed in the bonding member. The electrode and the support member can be easily energized.

  Furthermore, in the cartridge of the eleventh aspect, as described in the twelfth aspect of the present invention, it is preferable that the support member is formed with a recess for positioning the electrode at a position where the electrode is disposed.

  According to such a cartridge, displacement of the position of the electrode can be prevented by engaging the electrode and the recess. In addition, since the amount of the electrode protruding from the contact surface between the support member and the holding body can be reduced as compared with the case where the concave portion is not formed, the bonding material is easily separated from the support member due to the protrusion of the electrode. Can be prevented.

  Further, in the cartridge according to claim 11 or claim 12, the electrode may be configured to sandwich the holding body on the non-holding surface as described in claim 13, and the electrode is claimed in claim. 14 may be configured to have an urging force and press the holding body toward the photoconductor.

According to such a cartridge, since the electrode acts so as to be in close contact with the holding body, the electrode and the holding body can be reliably brought into contact with each other.
Furthermore, in the cartridge according to any one of claims 11 to 14, as in claim 15, the electrode is disposed at a position facing the photoconductor and on the non-holding surface side in the flocked area of the holding body. It is preferable that

  According to such a cartridge, even when the electrode is positioned between the holding body and the support member, the holding body is pressed to the photosensitive member side via the bristles, so that the holding body is lifted from the support member. Can be prevented.

  Further, in the cartridge according to any one of claims 11 to 14, the electrode is located at a position facing the photoconductor and a non-holding surface side in a non-flocked region of the holder as described in claim 16. May be arranged.

According to such a cartridge, even when an electrode is disposed between the holding body and the support member, it is possible to prevent a step from being formed in the flocked region.
Furthermore, in the cartridge of the sixteenth aspect, as in the seventeenth aspect, the holding body is pressed from the holding surface side to the non-holding surface side at the position where the electrode is disposed in the non-flocked region of the holding body. It is desirable to have a pressing member.

According to such a cartridge, since the holding body is pressed by the pressing member to the non-holding surface side where the electrode is positioned, it is possible to prevent the electrode and the holding body from being separated.
In addition, in the cartridge according to claim 17, the cartridge includes a first member having a brush, an electrode, and a support member, and a second member having a pressing member, and is configured by combining the members. When the second member is combined with the first member, the non-planted region of the holding body is pressed from the holding surface side to the non-holding surface side by the pressing member. It is preferable.

According to such a cartridge, when the members are combined, the adhesion between the electrode and the holder can be maintained.
In the cartridge according to any one of claims 9 to 18, the bonding material is preferably made of an insulating double-sided tape as described in claim 19.

  According to such a cartridge, since the insulating double-sided tape generally has a stronger adhesive force than the conductive double-sided tape, the holding body and the support member can be favorably bonded with a stronger adhesive force.

Furthermore, in the cartridge according to any one of claims 9 to 19, the support member may be insulative as described in claim 20.
According to such a cartridge, even if the supporting member is insulative, it is possible to energize from the electrode to the conductive portion of the holding body. Further, the first member can be integrally formed with a generally inexpensive resin material or the like.

Further, in the cartridge according to any one of claims 4 to 20, it is preferable that the electrode is disposed outside the image forming area by the photosensitive member as described in claim 21.
According to such a cartridge, it is possible to prevent the image from being affected by the arrangement of the electrodes.

  Furthermore, in the cartridge according to any one of claims 1 to 21, the brush may be used as a charging device for charging the photosensitive member. However, as described in claim 22, a voltage is applied to the brush hair. You may use as a cleaning brush apparatus which cleans the surface of a photoreceptor by being applied.

According to such a cartridge, the surface of the photoreceptor can be cleaned with this brush.
In addition, in the cartridge according to any one of claims 1 to 22, it is desirable to provide a photoreceptor as described in claim 23.

According to such a cartridge, since the photosensitive member is provided in the cartridge, maintenance (inspection and replacement) of the photosensitive member can be easily performed.
The invention according to claim 24 is configured such that a cartridge having a brush for applying a voltage to the surface of the photosensitive member can be mounted, and an electrostatic latent image is formed on the surface of the photosensitive member. An image forming apparatus that develops an electrostatic latent image with a developer and forms an image on a recording medium. The image forming apparatus includes the cartridge according to any one of claims 1 to 23, and the cartridge is mounted. When this is done, the power supply unit provided in the main body of the image forming apparatus and the power supply means of the cartridge are electrically connected so that power can be supplied from the main body of the image forming apparatus to the cartridge. .

  That is, in this image forming apparatus, when the cartridge according to any one of claims 1 to 23 is mounted, a power source provided outside the cartridge and inside the image forming apparatus (image forming apparatus main body) Power can be supplied to the cartridge from the unit.

Therefore, according to such an image forming apparatus, it is possible to supply power to the cartridge without disposing a power supply unit in the cartridge.
Next, an invention according to claim 25 is an image forming apparatus for forming an electrostatic latent image on the surface of a photoreceptor, developing the electrostatic latent image with a developer, and forming an image on a recording medium. A plurality of brush hairs are implanted in the holding body, contact with the surface of the photoconductor, and apply a voltage to the surface of the photoconductor; The brush holding body is made of a cloth formed of insulating fibers, and the brush bristles are in an upright state on a holding surface which is a surface on one side of the cloth. The bristles are planted so as to have a conductive portion formed with a conductive layer in contact with the bristles on a non-holding surface opposite to the holding surface, and the power feeding means is provided in the holding body. Powering the brush by contacting the conductive part It is a symptom.

  Therefore, according to such an image forming apparatus, since the conductive portion is formed on the non-holding surface side as in the case of using the cartridge according to claim 1, the material for forming the conductive portion is It is possible to prevent the brush hair from being attached to the photoreceptor. For this reason, it is possible to prevent adverse effects on image formation.

  In addition, since the power supply means can apply a voltage to the brush bristles well, the voltage can also be applied to the photoreceptor.

  FIG. 1 is a cross-sectional side view of a main part showing an embodiment of a laser printer as an image forming apparatus of the present invention. In FIG. 1, a printer 1 (an image forming apparatus referred to in the present invention) includes a feeder unit 4 for feeding a sheet 3 and a fed sheet 3 (a recording medium referred to in the present invention) in a main body casing 2. ) Includes an image forming unit 5 for forming an image.

  The feeder unit 4 includes a paper feed tray 6 that is detachably attached to the bottom of the main body casing 2, a paper pressing plate 7 provided in the paper feed tray 6, and an upper end of one end side of the paper feed tray 6. The paper feed roller 8 and the separation pad 9 provided in the paper, the paper dust removing rollers 10 and 11 provided on the downstream side of the paper feed direction of the paper 3 with respect to the paper feed roller 8, and the paper dust removing rollers 10 and 11 And a registration roller 12 provided on the downstream side in the transport direction (hereinafter, the downstream or upstream side in the transport direction of the paper 3 may be simply referred to as the downstream or upstream side).

  The sheet pressing plate 7 can stack the sheets 3 in a laminated form, and is supported so as to be swingable at the end far from the sheet feeding roller 8, so that the near end moves up and down. It is made possible, and is biased upward by a spring (not shown) from the back side. Therefore, the sheet pressing plate 7 is swung downward against the urging force of the spring, with the end far from the sheet feeding roller 8 as a fulcrum as the amount of stacked sheets 3 increases. The paper feed roller 8 and the separation pad 9 are arranged to face each other, and the separation pad 9 is pressed toward the paper feed roller 8 by a spring 13 provided on the back side of the separation pad 9.

  The uppermost sheet 3 on the sheet pressing plate 7 is pressed toward the sheet feeding roller 8 by a spring (not shown) from the back side of the sheet pressing plate 7, and the sheet feeding roller 8 and the separation pad are rotated by the rotation of the sheet feeding roller 8. After being sandwiched between 9, the sheet is fed one by one.

  The fed paper 3 is conveyed to the registration roller 12 after the paper dust is removed by the paper dust removing rollers 10 and 11. The registration roller 12 includes a pair of rollers facing each other, and the sheet 3 is sent to the image forming position after registration. The image forming position is a transfer position at which the toner image on the photosensitive drum 27 is transferred to the paper 3, and is a contact position between the photosensitive drum 27 and the transfer roller 30 in this embodiment.

  The feeder unit 4 further includes a multi-purpose tray 14, a multi-purpose side feed roller 15 and a multi-purpose side separation pad 25 for feeding the paper 3 stacked on the multi-purpose tray 14. ing. The multipurpose-side sheet feeding roller 15 and the multipurpose-side separation pad 25 are provided so as to face each other, and the spring 17 provided on the back side of the multipurpose-side separation pad 25 causes the multipurpose-side separation pad 25 to be It is pressed toward the roller 15.

  The sheets 3 stacked on the multi-purpose tray 14 are nipped between the multi-purpose side feed roller 15 and the multi-purpose side separation pad 25 by the rotation of the multi-purpose side feed roller 15 and then fed one by one. Paper.

The image forming unit 5 includes a scanner unit 16, a process cartridge 26 (or the photoconductor cartridge 51 corresponds to a cartridge in the present invention), a fixing unit 18, and the like.
The scanner unit 16 is provided at an upper portion in the main body casing 2 and includes a laser light emitting unit (not shown), a polygon mirror 19 that is driven to rotate, lenses 20 and 21, reflecting mirrors 22, 23, and 24. The laser beam based on the image data emitted from the laser emitting unit passes or reflects in the order of the polygon mirror 19, the lens 20, the reflecting mirrors 22 and 23, the lens 21, and the reflecting mirror 24, as indicated by the chain line, and processes. The surface of a photosensitive drum 27 (described later) of the cartridge 26 is irradiated with high-speed scanning.

  The process cartridge 26 is provided below the scanner unit 16 and includes a photosensitive cartridge 51 and a developing cartridge 28 that are detachably attached to the main casing 2 as shown in FIG. In the photosensitive cartridge 51, a photosensitive drum 27, a scorotron charger 29, a brush 54, and a transfer roller 30 are provided.

  The photoconductor cartridge 51 is divided into two parts in the vertical direction. That is, the photosensitive cartridge 51 is formed separately from the lower frame 26a (the supporting member and the first member in the present invention) and the lower frame 26a, and the upper frame 26b (the present invention) combined with the lower frame 26a from above. 2nd member).

  The developing cartridge 28 is detachably attached to the photoreceptor cartridge 51 and includes a developing roller 31, a layer thickness regulating blade 32, a supply roller 33, and a toner hopper 34.

  In the toner hopper 34, positively charged non-magnetic one-component toner is accommodated as a developer. Examples of the toner include polymerizable monomers such as styrene monomers such as styrene, and acrylic monomers such as acrylic acid, alkyl (C1 to C4) acrylate, and alkyl (C1 to C4) methacrylate. Polymerized toners obtained by copolymerization by a known polymerization method such as suspension polymerization are used. Such a polymerized toner is substantially spherical and has very good fluidity. Such a toner is blended with a colorant such as carbon black, wax, or the like, and an external additive such as silica is added to improve fluidity. The particle diameter is about 6 to 10 μm.

  Then, the toner in the toner hopper 34 is agitated by an agitator 36 supported by a rotating shaft 35 provided at the center of the toner hopper 34, and is discharged from a toner supply port 37 opened at a side portion of the toner hopper 34. Note that a toner remaining amount detection window 38 is provided on the side wall of the toner hopper 34 and is cleaned by a cleaner 39 supported by the rotating shaft 35.

  A supply roller 33 is rotatably provided at a side position of the toner supply port 37, and a developing roller 31 is rotatably provided facing the supply roller 33. The supply roller 33 and the developing roller 31 are in contact with each other in a state where they are compressed to some extent.

The supply roller 33 has a metal roller shaft covered with a roller portion made of a conductive foam material.
The developing roller 31 has a metal roller shaft covered with a roller portion made of a conductive rubber material. More specifically, the roller portion of the developing roller 31 has a urethane rubber or silicone rubber coating layer containing fluorine on the surface of a roller layer made of conductive urethane rubber or silicone rubber containing carbon fine particles. It is covered. A developing bias is applied to the developing roller 31 during development.

  A layer thickness regulating blade 32 is provided in the vicinity of the developing roller 31. The layer thickness regulating blade 32 includes a pressing portion 40 having a semicircular cross section made of insulating silicone rubber at the tip of a blade body made of a metal leaf spring material. 28, the pressing portion 40 is provided so as to be pressed against the developing roller 31 by the elastic force of the blade body.

  The toner discharged from the toner supply port 37 is supplied to the developing roller 31 by the rotation of the supply roller 33 in the arrow direction (counterclockwise direction). At this time, the toner is supplied between the supply roller 33 and the developing roller 31. Positively triboelectrically charged. The toner supplied onto the developing roller 31 enters between the pressing portion 40 of the layer thickness regulating blade 32 and the developing roller 31 as the developing roller 31 rotates in the arrow direction (counterclockwise). It is carried on the developing roller 31 as a thin layer having a constant thickness.

  The photosensitive drum 27 is supported by the lower frame 26a so as to be rotatable in the arrow direction (clockwise) in a state facing the developing roller 31 at a side position of the developing roller 31.

The photosensitive drum 27 includes a cylindrical drum body and a photosensitive layer made of polycarbonate or the like formed on the surface of the drum body.
The scorotron charger 29 is located above the photosensitive drum 27, upstream of the position facing the developing roller 31 in the rotational direction of the photosensitive drum 27 and downstream of the position facing the transfer roller 30 described later. In order not to come into contact with the photosensitive drum 27, they are opposed to each other at a predetermined interval and supported by the upper frame 26b. The scorotron charger 29 is a positively charged scorotron charger that generates corona discharge from a charging wire such as tungsten, and can uniformly charge the surface of the photosensitive drum 27 to a positive polarity. As is provided.

  As will be described in detail later, the brush 54 is a scorotron charger 29 in the side position of the photosensitive drum 27 (the side position opposite to the developing roller 31) and in the rotation direction of the photosensitive drum 27. Upstream of the position facing the transfer roller 30 and downstream of the position facing the transfer roller 30, the photoconductor drum 27 is disposed opposite to and supported between the lower frame 26 a and the upper frame 26 b.

  The brush 54 includes a large number of brush bristles 71 whose tips are in contact with the surface of the photosensitive drum 27. At the time of cleaning, a cleaning application power source (power source unit referred to in the present invention) provided in the main body casing 2 is provided on the brush member 53 via an electrode 56 described later (power supply means in the present invention: see FIG. 3 and the like). And an external power source).

  The transfer roller 30 is positioned below the photoconductive drum 27, upstream of the position facing the brush 54 in the rotation direction of the photoconductive drum 27 and downstream of the position facing the developing roller 31. And opposed to the lower frame 26a so as to be rotatable in the direction of the arrow (counterclockwise).

  The surface of the photosensitive drum 27 is uniformly positively charged by the scorotron charger 29 and then exposed by high-speed scanning of the laser beam from the scanner unit 16 to form an electrostatic latent image based on the image data. The

  Next, the electrostatic charge formed on the surface of the photosensitive drum 27 when the positively charged toner carried on the developing roller 31 comes into contact with the photosensitive drum 27 by the rotation of the developing roller 31. The latent image, that is, the surface of the photosensitive drum 27 that is uniformly positively charged, is supplied to an exposed portion that is exposed to a laser beam and the potential is lowered, and is visualized by being selectively carried. Thus, a toner image is formed by reversal development.

  Thereafter, the photosensitive drum 27 and the transfer roller 30 are rotationally driven so as to sandwich and convey the sheet 3 therebetween, and the sheet 3 is conveyed between the photosensitive drum 27 and the transfer roller 30. As a result, the toner image carried on the surface of the photosensitive drum 27 is transferred onto the paper 3.

  In the printer 1, so-called residual toner remaining on the surface of the photosensitive drum 27 after being transferred onto the paper 3 by the transfer roller 30 is collected by the developing roller 31 in a cleaner-less manner. If the remaining toner is collected by the cleaner-less method, it is not necessary to provide a mechanism and a storage unit for collecting the remaining toner, and the apparatus can be simplified and miniaturized.

  Further, after the transfer, the paper dust adhering to the surface of the photosensitive drum 27 due to the contact with the paper 3 causes the surface of the photosensitive drum 27 to be in contact with the brush member 53 of the brush 54 as the photosensitive drum 27 rotates. When facing each other, by applying a cleaning bias, the brush member 53 is electrically attracted and simultaneously entangled and removed from the surface of the photosensitive drum 27.

  As shown in FIG. 1, the fixing unit 18 is provided at a side position of the process cartridge 26 and on the downstream side in the sheet conveyance direction, and is disposed to face the heating roller 41 and the heating roller 41, and presses the heating roller 41. And a pair of conveying rollers 43 provided on the downstream side of the heating roller 41 and the pressing roller 42.

  The heating roller 41 is made of metal and has a halogen lamp for heating. The sheet 3 passes between the heating roller 41 and the pressing roller 42 through the toner image transferred onto the sheet 3 in the process cartridge 26. Then, the sheet 3 is heat-fixed in between, and then the sheet 3 is conveyed to the sheet discharge path 44 by the conveying roller 43.

The sheet 3 sent to the sheet discharge path 44 is conveyed to a sheet discharge roller 45 and is discharged onto the sheet discharge tray 46 by the sheet discharge roller 45.
In addition, the printer 1 is provided with a reverse conveyance unit 47 in order to form images on both sides of the paper 3. The reverse conveyance unit 47 includes a paper discharge roller 45, a reverse conveyance path 48, a flapper 49, and a plurality of reverse conveyance rollers 50.

  The paper discharge roller 45 includes a pair of rollers and is configured to be able to switch between forward rotation and reverse rotation. As described above, the paper discharge roller 45 rotates in the forward direction when the paper 3 is discharged onto the paper discharge tray 46, but rotates in the reverse direction when the paper 3 is reversed.

  The reverse conveyance path 48 is provided along the vertical direction so that the paper 3 can be conveyed from the paper discharge roller 45 to a plurality of reverse conveyance rollers 50 disposed below the image forming position. The upstream end is disposed near the paper discharge roller 45, and the downstream end is disposed near the reverse conveyance roller 50.

  The flapper 49 is provided so as to be able to swing so as to face a branch portion between the paper discharge path 44 and the reverse conveyance path 48, and the paper reversed by the paper discharge roller 45 by excitation or non-excitation of a solenoid (not shown). 3 is configured to be able to be switched from the direction toward the paper discharge path 44 to the direction toward the reverse conveyance path 48.

  A plurality of reverse conveyance rollers 50 are provided in a substantially horizontal direction above the paper feed tray 6, and the most upstream reverse conveyance roller 50 is disposed near the rear end of the reverse conveyance path 48, and The most downstream reverse conveying roller 50 is provided so as to be disposed below the registration roller 12.

  When images are formed on both sides of the paper 3, the reverse conveying unit 47 is operated as follows. That is, when the sheet 3 having an image formed on one side is conveyed from the sheet discharge path 44 to the sheet discharge roller 45 by the conveyance roller 43, the sheet discharge roller 45 rotates forward with the sheet 3 interposed therebetween. The paper 3 is once transported to the outside (the discharge tray 46 side), and when the majority of the paper 3 is sent to the outside and the rear end of the paper 3 is sandwiched between the paper discharge rollers 45, the paper 3 rotates forward. To stop. Next, the paper discharge roller 45 rotates in the reverse direction, and the flapper 49 switches the transport direction so that the paper 3 is transported to the reverse transport path 48, and the reverse transport path 48 in the reverse direction of the paper 3. To be transported. When the conveyance of the paper 3 is completed, the flapper 49 is switched to the original state, that is, the state where the paper 3 sent from the conveyance roller 43 is sent to the paper discharge roller 45.

  Next, the sheet 3 conveyed in the reverse direction to the reverse conveyance path 48 is conveyed to the reverse conveyance roller 50, reversed from the reverse conveyance roller 50 in the upward direction, and sent to the registration roller 12. The paper 3 conveyed to the registration roller 12 is turned upside down and sent again to the image forming position after registration, whereby an image is formed on both sides of the paper 3.

Next, the brush 54 will be described. FIG. 3 is an explanatory view showing the brush 54.
As shown in FIG. 3A, the brush 54 includes a base cloth 72 (a holding body referred to in the present invention) made of an insulating woven cloth and a large number of brush bristles 71. The brush 54 is planted so that a large number of bristles 71 are upright on the base cloth 72. The base cloth 72 is impregnated with a conductive fluid from the non-holding surface side opposite to the holding surface on which the brush bristles 71 are planted, and then solidified, whereby the backcoat layer 73 (in the present invention) is obtained. A conductive portion) is formed. Here, the conductive fluid impregnated in the base fabric 72 is made of, for example, an acrylic emulsion containing carbon or SBR (styrene-butylene rubber), and the base fabric 72 does not reach the holding surface side of the base fabric 72. The amount impregnated in is adjusted. For this reason, the base fabric 72 has a layer not impregnated with the conductive fluid and a layer impregnated with the conductive fluid (backcoat layer 73). Further, the brush bristles 71 are not planted on the entire holding surface, and the brush bristles 71 are planted on the longitudinal ends of the brush 54 (the front end in FIG. 3A). There are no non-planted areas.

The brush 54 is attached to the lower frame 26a of the process cartridge 26 with a double-sided tape 74 (a bonding material referred to in the present invention).
The double-sided tape 74 is coated with an insulating adhesive, and is bonded to a predetermined position of the lower frame 26a with one surface bonded in advance to the base cloth 72 side, whereby the brush 54 and the lower frame are bonded. 26a is bonded.

  And the electrode 75 which contacts the holding surface side of the base fabric 72 in this state is arrange | positioned. The electrode 75 is set to be pressed from the holding surface side toward the non-holding surface side so that the base fabric 72 is in close contact with the lower frame 26 a in the vicinity of the brush 54. The electrode 75 is configured such that one end is in contact with the base fabric 72 and the other end (contact portion 75c) protrudes outside the lower frame 26a.

  That is, since the process cartridge 26 does not have a cleaning application power source, the electrode 75 is protruded to the outside of the lower frame 26 a so that power can be supplied from the cleaning application power source provided in the main body casing 2. It is. With this configuration, when the process cartridge 26 is correctly attached to the printer 1, an electrode (not shown) extending from the power supply unit on the main body side of the printer 1 and the electrode 75 provided on the process cartridge 26 come into contact with each other at the contact portion 75c. As a result, a voltage is applied to the electrode 75.

  The lower frame 26a is formed with a notch 80 at a position where the electrode 75 is disposed, and the electrode 75 and the notch 80 are engaged so that the position of the electrode 75 does not shift. Yes.

  By the way, even if a voltage is applied to the electrode 75, the base cloth 72 is insulative. Therefore, if no current is supplied from the holding surface side of the base cloth 72 to the back coat layer 73, a voltage is applied to the brush bristles 71. Can not do it.

  For this reason, in this embodiment, for example, as shown in FIG. That is, the conductive fibers similar to the brush bristles 71 are partially woven into the base fabric 72 even in the non-flocked region.

  Here, when the bristles 71 are planted on the base cloth 72, for example, as shown in FIG. 4, the bristles 71 are formed in a state in which the two base cloths 72 are opposed to each other with a predetermined distance therebetween. A plurality of piles 76 are sewn between the two base fabrics 72. And this pile 76 is each sewn only to one base fabric 72 in a non-flocked area | region. After the pile 76 is sewn into the base fabric 72 in this way, two brushes 54 as shown in FIG. 3B are formed by cutting at the center.

  In the printer 1 described in detail above, the base fabric 72 is formed of insulating fibers, and the brush bristles 71 are in an upright state on the holding surface that is one surface of the base fabric 72. The bristles 71 are implanted in such a manner that the back coat layer 73 is formed by impregnating the non-holding surface opposite to the holding surface with the conductive fluid. Power is supplied to the brush 54 by contacting the backcoat layer 73 in the region.

  Further, the insulating lower frame 26a that supports the non-holding surface side of the base fabric 72, and the base fabric 72 and the lower frame 26a are joined together by an insulating double-sided tape 74 disposed therebetween. The electrode 75 is disposed outside the image forming area formed by the photosensitive drum 27.

  Therefore, according to such a printer 1, it is possible to prevent the conductive fluid from being transmitted through the bristles 71 and adhering to the photosensitive drum 27, and thus it is possible to prevent adverse effects on image formation. .

In addition, since the electrode 75 can apply a voltage to the brush bristles 71, the voltage can also be applied to the photosensitive drum 27.
Furthermore, since the bristle 71 does not get in the way when the electrode 75 is disposed, the electrode 75 can be easily disposed.

  Further, since the entire surface of the non-holding surface side of the base fabric 72 is fixedly supported by the insulating double-sided tape 74, the entire brush bristles 71 can be brought into good contact with the photosensitive drum 27. In particular, since the insulating double-sided tape generally has a stronger adhesive force than the conductive double-sided tape, the base fabric 72 and the lower frame 26a can be satisfactorily bonded with a stronger adhesive force.

Furthermore, since the lower frame 26a does not need to be conductive, the lower frame 26a can be integrally formed with a generally inexpensive resin material or the like.
By the way, in the printer 1, the brush 54 is used as a cleaning brush 54 device that cleans the surface of the photosensitive drum 27 by applying a voltage to the bristle 71. Can be cleaned.

Further, since the pile 76 is woven into the non-flocked region in the step of planting the brush bristles 71, there is no need to newly provide a step of weaving the pile 76.
The embodiment of the present invention is not limited to the above-described embodiment, and can take various forms as long as it belongs to the technical scope of the present invention.

  For example, in the present embodiment, in order to make the electrode 75 and the back coat layer 73 conductive, in the step of weaving the brush hair 71, the pile 76 is woven into the non-flocked region. Instead, conductive fibers similar to or different from the pile 76 may be configured to be woven in a process different from the process of weaving the brush bristles 71.

Specifically, as shown in FIG. 3 (c), the conductive fiber may be woven only in the region in the base fabric 72 that contacts the electrode 75 and the vicinity thereof.
If it does in this way, the usage-amount of electroconductive fiber can be decreased more.

  Further, as shown in FIG. 5A, in the non-flocked region of the base fabric 72, a conductive fluid is impregnated from the holding surface side and solidified to form a current-carrying portion 77. You may make it conduct | electrically_connect from 75 to the backcoat layer 73. FIG.

  Further, as shown in FIG. 5B, the back coat layer 73 may be folded back so as to be on the holding surface side in the non-flocked region, and the electrode 75 may be in contact with the folded back coat layer 73.

  In addition, as shown in FIG. 6A, an electrode 75 having a tip 75a having a sharp tip is used, and the tip 75a of the electrode 75 is back coated by penetrating the tip 75a into the base cloth 72. You may comprise so that it may contact the layer 73 directly. Moreover, although the electrode 75 shown to Fig.6 (a) has only one front-end | tip part 75a penetrated to the base fabric 72, it may have two or more front-end | tip parts 75a.

Particularly in this case, since the plurality of tip portions 75 a come into contact with the backcoat layer 73, more stable power can be supplied from the electrode 75 to the brush bristles 71.
In addition, as shown in FIG. 6B, the electrode 75 may be brought into direct contact with a part of the bristles 71.

  In this case, the electrode 75 is not in contact with the electrode 75 via the brush bristles 71 and the back coat layer 73 with which the electrode 75 is in contact without adversely affecting the photosensitive drum 27 with the conductive fluid. It is possible to conduct to the bristle 71.

  Here, in the present embodiment, the electrode 75 is brought into contact with the holding surface side of the base fabric 72, but it is not necessary to configure in this way, and the electrode 75 is directly attached to the non-holding surface side of the base fabric 72. You may comprise so that it may contact.

  Specifically, for example, as shown in FIG. 7A, a part of the back coat layer 73 (non-holding surface) is exposed at a portion where the electrode 75 is previously arranged in the lower frame 26a and the double-sided tape 74. A notch 81 is formed, and an electrode 75 is disposed in the notch 81 as shown in FIG. In addition, in the brush 54 shown in FIG.7 (b), the electrode 75 is arrange | positioned at two places of the hair transplant area | region of the base fabric 72, and a non-hair transplant area | region.

  Further, as shown in FIG. 7C, it is further preferable that the tip of the electrode 75 is bent so that the thickness of the electrode 75 is slightly larger than the thickness of the lower frame 26a and the double-sided tape 74. . That is, it is better to adopt a configuration in which the brush 54 is pressed against the photosensitive drum 27 by the electrode 75.

  Further, as shown in FIG. 7B, the lower frame 26 a includes a pressing portion 26 c (a pressing member in the present invention) between the non-planted region of the brush 54 and the photosensitive drum 27. The pressing portion 26 c comes into contact with the holding surface of the base cloth 72, and when the base cloth 72 is pressed in the direction of the photosensitive drum 27 by the electrode 75, the pressing force by the electrode 75 is brought into contact with the base cloth 72. Is set to receive.

Therefore, even in the printer 1 equipped with such a brush 54, the same effect as described above can be obtained.
In addition to the above-described effects, particularly in the printer 1, the double-sided tape 74 is previously laminated on the base cloth 72, and can be joined to the brush by simply contacting the lower frame 26a. Assembling of the cartridge provided with 54 can be facilitated.

Moreover, since the notch 81 is formed in the double-sided tape 74, the electrode 75 and the lower frame 26a can be easily energized.
Further, when the electrode 75 presses the brush 54 against the photosensitive drum 27, the electrode 75 acts so as to be in close contact with the base cloth 72, and the base cloth 72 is moved to the non-holding surface side where the electrode 75 is located by the pressing portion 26c. Since it is pressed, the electrode 75 and the base cloth 72 are in close contact with each other, and the electrode 75 and the base cloth 72 can be prevented from being peeled off.

  Further, the brush 54 shown in FIG. 7 is configured to receive the pressing force by the electrode 75 using the pressing portion 26c provided in the lower frame 26a. However, as shown in FIG. 8, the pressing portion 26d is applied to the upper frame 26b. (Pressing member referred to in the present invention) may be provided, and the pressing force by the electrode 75 may be received by using the pressing portion 26d provided on the upper frame 26b by combining the frames. Further, in the printer 1, the electrode 75 is disposed at a position facing the photosensitive drum 27 and on the non-holding surface side in the non-flocked region of the base fabric 72.

Therefore, according to the printer 1, when the frames are combined, the adhesion between the electrode 75 and the base fabric 72 can be maintained.
Further, even when the electrode 75 is disposed between the base fabric 72 and the lower frame 26a, it is possible to prevent a step from being formed in the flocked region.

  Further, in the embodiment shown in FIG. 7 and FIG. 8, the notch 81 is provided not only on the double-sided tape 74 but also on the portion where the electrode 75 of the lower frame 26a is arranged, but as shown in FIG. 9A. Alternatively, the notch 81 may be formed only in the double-sided tape 74, and the notch 81 may not be formed in the lower frame 26a.

  In this case, as shown in FIG. 9B, a recess 82 for positioning the electrode 75 is formed in a portion where the electrode 75 is disposed on the surface of the lower frame 26a that contacts the double-sided tape 74. Good.

  Therefore, according to such a printer 1, the displacement of the position of the electrode 75 can be prevented by engaging the electrode 75 and the recess 82. Further, since the amount of the electrode 75 protruding from the contact surface between the lower frame 26a and the base fabric 72 can be reduced as compared with the case where the concave portion 82 is not formed, the double-sided tape 74 is caused to protrude from the lower frame 26a by the protrusion of the electrode 75. Can be prevented from being easily peeled off.

  Further, as described above, even when the electrode 75 is in contact with the backcoat layer 73 of the base fabric 72, the electrode 75 is formed by connecting the base fabric 72 and the lower frame 26a as shown in FIG. You may comprise so that it may be clamped. Further, when the notch 81 is formed in the lower frame 26a, a step 75b corresponding to the thickness of the lower frame 26a and the double-sided tape 74 may be formed in the electrode 75.

Even with such a printer 1, the same effect as the printer 1 can be obtained.
In each of the above embodiments, the brush 54 is used as a cleaning brush for cleaning the surface of the photosensitive drum 27. However, for example, the brush 54 may be used as a charging brush for charging the photosensitive drum 27. Good.

  Furthermore, in the above-described embodiment, the process cartridge 26 is configured to be separable into the photosensitive cartridge 51 and the developing cartridge 28. However, the present invention is not limited to this configuration, and the photosensitive cartridge 51 and the developing cartridge 28 may be separated. You may be comprised integrally.

It is principal part side sectional drawing which shows a laser printer. It is a sectional side view which shows a process cartridge. It is explanatory drawing which shows the contact state of a brush and an electrode. It is explanatory drawing which shows the manufacturing method of a brush. It is explanatory drawing which shows the contact state of the brush and electrode of a modification (what makes an electrode contact from the holding surface side). It is explanatory drawing which shows the contact state of the brush and electrode of a modification (what makes an electrode contact from the holding surface side). It is explanatory drawing which shows the contact state of the brush and electrode of a modification (what makes an electrode contact from the non-holding surface side). It is explanatory drawing which shows the contact state of the brush and electrode of a modification (what makes an electrode contact from the non-holding surface side). It is explanatory drawing which shows the contact state of the brush and electrode of a modification (what makes an electrode contact from the non-holding surface side). It is explanatory drawing which shows the contact state of the brush and electrode of a modification (what makes an electrode contact from the non-holding surface side).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Printer, 2 ... Main body casing, 3 ... Paper, 4 ... Feeder part, 5 ... Image forming part, 16 ... Scanner part, 18 ... Fixing part, 26 ... Process cartridge, 26a ... Lower frame, 26b ... Upper frame, 26c , 26d ... pressing portion, 27 ... photoconductor drum, 28 ... developing cartridge, 29 ... scorotron charger, 30 ... transfer roller, 31 ... developing roller, 51 ... photoconductor cartridge, 53 ... brush member, 54 ... brush, 55 ... Brush holder, 56 ... Electrode, 71 ... Brush hair, 72 ... Base cloth, 73 ... Back coat layer, 74 ... Double-sided tape, 75 ... Electrode, 75a ... Tip, 75b ... Step part, 75c ... Contact part, 76 ... Pile, 77 ... energization part, 80, 81 ... notch part, 82 ... recess.

Claims (25)

A cartridge that is detachably mountable to an image forming apparatus that forms an electrostatic latent image on a surface of a photoreceptor, develops the electrostatic latent image with a developer, and forms an image on a recording medium. ,
A brush for applying a voltage to the surface of the photoreceptor, in which a large number of brush hairs are implanted in the holding body, contacting the surface of the photoreceptor,
Power supply means for receiving a power supply from an external power source and applying a voltage to the brush;
With
The brush holding body is made of a cloth formed of insulating fibers, and the brush hair is implanted so that the brush hair is in an upright state on a holding surface which is one side of the cloth. A conductive portion having a conductive layer in contact with the bristles on the non-holding surface opposite to the holding surface;
The cartridge, wherein the power feeding means feeds power to the brush by contacting a conductive portion of the holding body.   The cartridge according to claim 1, wherein the conductive portion is formed by impregnating a conductive fluid. The holding body has a flocked region in which the brush bristles are flocked and a non-flocked region in which the brush bristles are not flocked,
The cartridge according to claim 1, wherein the power feeding unit feeds power to the brush by contacting a conductive portion in a non-flocked region of the holding body. Woven into the non-flocked region of the holding body, comprising conductive fibers that can be energized with the conductive portion of the holding body,
The cartridge according to claim 3, wherein the power feeding unit includes an electrode in contact with the conductive fiber. The holding surface side of the non-flocked region of the holding body is impregnated with a conductive fluid and provided with a current-carrying part formed by solidification,
The cartridge according to claim 3, wherein the power supply unit includes an electrode in contact with the energization unit.   The power supply means includes an electrode that contacts the conductive portion of the holding body by penetrating from the holding surface side in the non-flocked region of the holding body toward the non-holding surface side opposite to the holding surface. The cartridge according to claim 3. The non-planted region of the holding body is located at an end of the holding body,
The power supply means includes an electrode that contacts the folded non-holding surface in a state where the non-holding surface opposite to the holding surface is folded back to the holding surface side in the non-flocked region of the holding body. The cartridge according to claim 3.   The cartridge according to claim 1, wherein the power supply unit includes an electrode that directly contacts at least a part of the brush bristles. A support member that supports a non-holding surface side opposite to the holding surface of the holding body;
A bonding material that is disposed between the holding body and the support member, and joins the holding body and the support member;
The cartridge according to any one of claims 1 to 8, wherein the cartridge is provided. A support member that supports a non-holding surface side opposite to the holding surface of the holding body;
In a state of being laminated so as to be in contact with the entire surface of the non-holding surface of the holding body, by being brought into contact with the support member, a bonding material for bonding the holding body and the support member;
The cartridge according to claim 1 or 2, further comprising: In the bonding material, on the non-holding surface side of the holding body, a notch portion that is notched so as to expose a part of the non-holding surface is formed,
The power supply means includes an electrode that is disposed between the non-holding surface of the holding body and the support member and at a position where a cutout portion of the bonding material is formed, and that contacts the non-holding surface of the holding body. The cartridge according to claim 10. The cartridge according to claim 11, wherein the support member has a recess for positioning the electrode at a position where the electrode is disposed.   The cartridge according to claim 11 or 12, wherein the electrode sandwiches a holding body by the non-holding surface.   The cartridge according to claim 11, wherein the electrode has an urging force that presses the holding body toward the photoreceptor. The holding body has a flocked region in which the brush bristles are flocked and a non-flocked region in which the brush bristles are not flocked,
The cartridge according to any one of claims 11 to 14, wherein the electrode is disposed at a position facing the photoconductor and on a non-holding surface side in a flocking region of the holding body. The holding body has a flocked region in which the brush bristles are flocked and a non-flocked region in which the brush bristles are not flocked,
The cartridge according to any one of claims 11 to 14, wherein the electrode is disposed at a position facing the photoconductor and on a non-holding surface side in a non-planted region of the holding body. .   17. The pressing member according to claim 16, further comprising: a pressing member that presses the holding body from the holding surface side to the non-holding surface side at a position where the electrode is disposed in the non-flocked region of the holding body. cartridge. The cartridge includes a first member having the brush, the electrode, and the support member, and a second member having the pressing member, and is configured by combining the members.
When the second member is combined with the first member, the non-planted region of the holding body is pressed from the holding surface side to the non-holding surface side by the pressing member. The cartridge described.   The cartridge according to any one of claims 9 to 18, wherein the bonding material is made of an insulating double-sided tape.   The cartridge according to any one of claims 9 to 19, wherein the support member is insulative.   21. The cartridge according to claim 4, wherein the electrode is disposed outside an image forming area formed by the photoconductor.   The cartridge according to any one of claims 1 to 21, wherein the brush is used as a cleaning brush device that cleans the surface of the photosensitive member by applying a voltage to the bristles.   The cartridge according to any one of claims 1 to 22, wherein the cartridge includes at least the photosensitive member. A cartridge having a brush for applying a voltage to the surface of the photosensitive member can be mounted. An electrostatic latent image is formed on the surface of the photosensitive member, and the electrostatic latent image is developed with a developer. An image forming apparatus for forming an image on a medium,
The cartridge according to any one of claims 1 to 23 is provided as the cartridge.
When the cartridge is mounted, a power supply unit provided in the main body of the image forming apparatus and a power supply unit of the cartridge are electrically connected so that power can be supplied from the main body of the image forming apparatus to the cartridge. An image forming apparatus. An image forming apparatus that forms an electrostatic latent image on the surface of a photoreceptor, develops the electrostatic latent image with a developer, and forms an image on a recording medium,
A brush for applying a voltage to the surface of the photoreceptor, in which a large number of brush hairs are implanted in the holding body, contacting the surface of the photoreceptor,
Power supply means for receiving a power supply from a power supply unit and applying a voltage to the brush;
With
The brush holding body is made of a cloth formed of insulating fibers, and the brush hair is implanted so that the brush hair is in an upright state on a holding surface which is one side of the cloth. A conductive portion having a conductive layer in contact with the bristles on the non-holding surface opposite to the holding surface;
The image forming apparatus, wherein the power feeding unit feeds power to the brush by contacting a conductive portion of the holding body.

Images