JP4770482B2 - Developing device, image forming apparatus, and image forming system - Google Patents

Description

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

  As a developing device for developing using toner particles, a toner particle carried by a toner particle carrying roller facing an opening provided in a housing of the developing device is used as a latent image on an image carrier provided outside the developing device. There is known a developing device that develops the toner image (see Patent Document 1, for example).

Such a developing device is provided with a transmission gear for transmitting power from a drive source to rotate the toner particle carrying roller at the end of the toner particle carrying roller. An oblique gear is used as the transmission gear, and by increasing the meshing width of the gear, the space occupied by the transmission gear is reduced to reduce the size of the developing device while suppressing the occurrence of uneven rotation. . Further, since the toner particle carrying roller faces the opening provided in the housing, a seal member is provided so that the toner particles do not leak from between the housing and the toner particle carrying roller.
JP-A-8-129306

  However, when power is transmitted to the toner particle carrying roller via the inclined gear and the toner particle carrying roller rotates, an external force in the thrust direction acts on the toner particle carrying roller. At this time, when the toner particle carrying roller moves in the thrust direction by the external force, there is a problem that the sealing property may be deteriorated due to a change in the contact state between the toner particle carrying roller and the seal member.

  The present invention has been made in view of such a problem, and the object of the present invention is to prevent the toner particle carrying roller from being interposed between the housing and the toner particle carrying roller even if power is transmitted to the toner particle carrying roller via the inclined gear. It is to realize a developing device capable of suppressing leakage of toner particles, an image forming apparatus having the developing device, and an image forming system.

A main aspect of the present invention is a developing device having a toner particle carrying roller that is urged in a predetermined direction along an axis when rotated by power transmitted through an inclined gear, and (a) an image carrier A housing in which toner particles for developing a latent image carried on the housing are accommodated, and (b) an opening communicating with the inside and outside of the housing, and a central portion of the surface for carrying the toner particles , A first groove for moving toner particles in a predetermined direction and a second groove for moving toner particles in a direction opposite to the predetermined direction are inclined with respect to the axial direction in the axial direction. A toner particle carrying roller which is formed in a spiral at an equal pitch and in which the second groove portion has a higher toner particle transfer efficiency than the first groove portion; and (c) both end portions of the toner particle carrying roller. In front of the peripheral surface And the end seal for sealing the gap between the housing, a developing device and having an (d).

  Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

  At least the following will be made clear by the description of the present specification and the accompanying drawings.

  A developing device having a toner particle-carrying roller that is urged in a predetermined direction along an axis when rotated by power transmitted through an inclined gear, and (a) a latent image carried on an image carrier. A housing for accommodating toner particles for developing an image; and (b) an opening communicating with the inside and outside of the housing for moving the toner particles to the center of the surface for carrying the toner particles. At least one groove portion has a predetermined inclination with respect to the axial direction and is formed in a spiral shape at an equal pitch in the axial direction, and all the groove portions move toner particles in a direction opposite to the predetermined direction. (C) an end seal for sealing a gap between the toner particle carrying roller and (c) the toner particle carrying roller at both ends of the toner particle carrying roller and sealing the gap between the housing and (d). Current It is a device.

  When rotating, the toner particle carrying roller is biased in a predetermined direction along the axial direction, and may be moved in the predetermined direction by the biased force. At this time, the toner particles carried on the toner particle carrying roller are also moved in a predetermined direction. When the toner particle carrying roller moves in the axial direction, the contact state with the end seals that are in contact with the peripheral surface at both ends of the toner particle carrying roller changes, and the toner particle carrying roller moves toward the predetermined direction side of the toner particle carrying roller. In the vicinity of the provided end seal, there is a tendency that more toner particles are collected than other parts. That is, by collecting a larger amount of toner particles than before the toner particle carrying roller is moved, the pressing force of the toner particles to the end seal is increased, or the sealing performance by the end seal is reduced due to a change in the contact state. Then, the toner particles may leak to the outside of the housing.

  Even in such a case, the toner particle carrying roller has a predetermined inclination with respect to the axial direction and has a spiral groove portion at an equal pitch in the axial direction, and all the groove portions allow the toner particles to pass through the toner particles. According to the developing device as described above that moves in the direction opposite to the predetermined direction, the toner particles are moved in the direction opposite to the predetermined direction as the toner particle carrying roller rotates. For this reason, even if the toner particle carrying roller is moved in a predetermined direction, it is possible to prevent the toner particles from being collected near the end seal provided on the predetermined direction side of the toner particle carrying roller. Therefore, even if the toner particle carrying roller moves in a predetermined direction, it is possible to prevent the toner particles from leaking outside the housing.

  In addition, the developing device includes a toner particle carrying roller that is urged in a predetermined direction along an axis when rotated by power transmitted through the inclined gear, and is (a) carried on the image carrier. A housing in which toner particles for developing the latent image are accommodated; and (b) an opening communicating with the inside and outside of the housing, and in the center of the surface for carrying the toner particles in the predetermined direction. The first groove for moving the toner particles and the second groove for moving the toner particles in the direction opposite to the predetermined direction are inclined at an equal pitch in the axial direction with an inclination with respect to the axial direction. A toner particle carrying roller that is formed in a spiral shape and has a toner particle transfer efficiency higher in the second groove than the first groove, and (c) a circumferential edge at both ends of the toner particle carrying roller. Abuts the surface and the housing And the end seal for sealing the gap between a developing apparatus is characterized in that it has a (d).

  When rotating, the toner particle carrying roller is biased in a predetermined direction along the axial direction, and may be moved in the predetermined direction by the biased force. At this time, the toner particles carried on the toner particle carrying roller are also moved in a predetermined direction. When the toner particle carrying roller is moved in the axial direction, the contact state with the end seals that are in contact with the peripheral surface at both ends of the toner particle carrying roller changes, and the toner particle carrying roller has a predetermined direction. In the vicinity of the end seal provided on the side, there is a tendency that more toner particles are collected than other parts. That is, by collecting a larger amount of toner particles than before the toner particle carrying roller is moved, the pressing force of the toner particles to the end seal is increased, or the sealing performance by the end seal is reduced due to a change in the contact state. Then, the toner particles may leak to the outside of the housing.

  Even in such a case, the second groove portion for moving the toner particles in the direction opposite to the predetermined direction is more efficient in moving the toner particles than the first groove portion for moving the toner particles in the predetermined direction. According to the developing device having a high toner particle carrying roller, the toner particles moved by the rotation of the toner particle carrying roller are more moved by the second groove than the first groove. More toner particles are moved in a direction opposite to the predetermined direction. For this reason, even if the toner particle carrying roller is moved in a predetermined direction, it is possible to prevent the toner particles from being collected near the end seal provided on the predetermined direction side of the toner particle carrying roller. Therefore, even if the toner particle carrying roller is moved in a predetermined direction, it is possible to prevent the toner particles from leaking outside the housing.

In such a developing device, it is preferable that the movement efficiency of the toner particles is increased by making the depth of the second groove portion deeper than the depth of the first groove portion.
According to such a developing device, by making the depth of the second groove portion deeper than the depth of the first groove portion, the movement efficiency of the toner particles in the second groove portion can be easily increased as compared with the first groove portion. It is possible to move more toner particles in a direction opposite to the predetermined direction than in the predetermined direction.

In such a developing device, the movement efficiency of the toner particles may be enhanced by making the width of the second groove portion wider than the width of the first groove portion.
According to such a developing device, by making the width of the second groove portion wider than the width of the first groove portion, it is possible to easily increase the toner particle movement efficiency of the second groove portion than that of the first groove portion. When the toner particle carrying roller rotates, the toner particles can be moved more in a direction opposite to the predetermined direction than in the predetermined direction.

In such a developing device, it is preferable that the first groove portion and the second groove portion intersect each other to form a lattice shape.
According to such a developing device, since the first groove portion and the second groove portion cross each other, the toner particles once started to roll along the first groove portion or the second groove portion are halfway. It is possible to roll along the second groove portion or the first groove portion. For this reason, it is possible to move the toner particles more in a direction opposite to the predetermined direction than in the predetermined direction, and to suppress the movement direction of the toner particles from being extremely biased.

In such a developing device, the movement efficiency of the toner particles may be enhanced by making an inclination angle of the second groove portion with respect to the axial direction smaller than an inclination angle of the first groove portion with respect to the axial direction.
According to such a developing device, the movement angle of the toner particles in the second groove portion can be easily increased by making the inclination angle of the second groove portion with respect to the axial direction smaller than the inclination angle with respect to the axial direction of the first groove portion. It is possible to move the toner particles more than the predetermined direction, and it is possible to move the toner particles more in a direction opposite to the predetermined direction than in the predetermined direction.

In such a developing device, it is preferable that a distance between the end of the second groove and the end seal is shorter than a distance between the end of the first groove and the end seal.
According to such a developing device, since the distance between the end of the second groove and the end seal is shorter than the distance between the end of the first groove and the end seal, the toner particles are moved in a predetermined direction. The end of the first groove is farther from the end seal than the end of the second groove. For this reason, it is possible to suppress the amount of toner particles toward the end seal side.

In the developing device, when the toner particle carrying roller is rotated via the inclined gear, the toner particle carrying roller is moved in the predetermined direction, and a part of the groove is opposed to the end seal. It is characterized by that.
When the toner particle carrying roller is moved in a predetermined direction and a part of the groove part is opposed to the end seal, the sealing performance of the end seal in the groove part may be deteriorated. If the developing device moves more in the direction opposite to the predetermined direction, leakage of toner particles can be suppressed even if a part of the groove and the end seal face each other.

In such a developing device, the housing has a positioning protrusion that is positioned along the end seal only on the outer side in the axial direction of the end seal.
When the housing is provided with a positioning protrusion that is positioned along the end seal only on the outer side in the axial direction of the end seal, the toner particles are moved when the toner particle carrying roller is moved in a predetermined direction. The end seal in contact with the peripheral surface of the carrier roller cannot move outward in the axial direction. For this reason, when the toner particle carrying roller is moved in a predetermined direction, the end seal may be bent, or the end seal may be deformed and the sealing performance may be deteriorated. However, if the developing device moves the toner particles more in a direction opposite to the predetermined direction than the predetermined direction as described above, even if the end seal is bent or deformed, the toner particles leak out. Can be suppressed.

In such a developing device, it is desirable that the depth of the groove is not more than twice the volume average particle diameter of the toner particles.
According to such a developing device, since the depth of the groove is not more than twice the volume average particle diameter of the toner particles, two or more toner particles entering the groove do not overlap in the depth direction in the groove. . For this reason, it is possible to charge the toner particles in the groove portion satisfactorily by rolling them uniformly.

In such a developing device, it is desirable that the peripheral surface other than the groove portion in the central portion of the toner particle carrying roller carry the toner particles.
According to such a developing device, since the peripheral surface other than the groove portion in the central portion of the toner particle carrying roller carries toner particles, the toner particle carrying roller has both the groove portion and the peripheral surface other than the groove portion. Supports toner particles. Therefore, by making the surface of the toner particle carrying roller face the image carrier, it is possible to develop the latent image while suppressing density unevenness in the entire portion of the image carrier facing the surface of the toner particle carrying roller. It is.

In the developing device, the toner particle carrying roller has a layer thickness regulating member for regulating a layer thickness of the toner particle, and the toner particle carried on the surface is formed by the layer thickness regulating member. It is desirable that the layer thickness be regulated by being pressed by the flat surface.
According to such a developing device, the toner particles carried on the surface of the toner particle carrying roller are regulated in the layer thickness by the plane of the layer thickness regulating member, so that the surface of the toner particle carrying roller, in particular, The toner particles carried on the peripheral surface other than the groove are not completely scraped off by the layer thickness regulating member. That is, it is possible to regulate the layer thickness of the toner particles in a state where the toner particles are carried on the groove portion of the toner particle carrying roller and on the peripheral surface other than the groove portion. Further, since the toner particles carried on the surface are pressed by the flat surface of the layer thickness regulating member, any one of the surface of the toner particle carrying roller, the layer thickness regulating member, and the toner particles and the toner particles are mutually connected. By rubbing, it is possible to charge the toner particles well.

In addition, the developing device includes a toner particle carrying roller that is urged in a predetermined direction along an axis when rotated by power transmitted through the inclined gear, and is (a) carried on the image carrier. A housing in which toner particles for developing the latent image are accommodated; and (b) an opening communicating with the inside and outside of the housing, and in the center of the surface for carrying the toner particles in the predetermined direction. The first groove for moving the toner particles and the second groove for moving the toner particles in the direction opposite to the predetermined direction are inclined at an equal pitch in the axial direction with an inclination with respect to the axial direction. A toner particle carrying roller that is formed in a spiral shape and has a toner particle transfer efficiency higher in the second groove than the first groove, and (c) a circumferential edge at both ends of the toner particle carrying roller. Abuts the surface and the housing (D) the first groove and the second groove intersect each other to form a lattice shape, and (e) the toner particles The movement efficiency is increased by making the inclination angle of the second groove portion with respect to the axial direction smaller than the inclination angle of the first groove portion with respect to the axial direction, and (f) the toner particle carrying roller is moved to the inclined gear. , The toner particle carrying roller is moved in the predetermined direction, a part of the groove is opposed to the end seal, and (g) the housing is the shaft of the end seal. And (h) the depth of the groove is not more than twice the volume average particle diameter of the toner particles, and (i) ) Of the toner particle carrying roller The peripheral surface of the central portion other than the groove portion carries the toner particles, and (j) has a layer thickness regulating member for regulating the layer thickness of the toner particles carried on the toner particle carrying roller, The toner particles carried on the surface are pressed by a plane of the layer thickness regulating member to regulate the layer thickness.
According to such a developing device, all of the above-described effects can be obtained, so that the object of the present invention can be achieved most effectively.

  And (A) a developing device having a toner particle carrying roller that is urged in a predetermined direction along an axis when rotated by power transmitted through an inclined gear, and (a) an image carrier. A housing in which toner particles for developing a latent image carried on the toner are housed; and (b) a toner particle facing an opening communicating with the inside and outside of the housing and in the center of the surface for carrying the toner particles At least one groove portion for moving the toner is formed in a spiral shape having a predetermined inclination with respect to the axial direction and at an equal pitch in the axial direction, and all the groove portions have toner particles in the predetermined direction. Development comprising: a toner particle carrying roller that moves in the opposite direction; and (c) an end seal that is in contact with the peripheral surface at both ends of the toner particle carrying roller and seals the gap with the housing Equipment, For example, it can also be implemented image forming apparatus and forming an image using the developing device (B).

  And (A) a developing device having a toner particle carrying roller that is urged in a predetermined direction along an axis when rotated by power transmitted through an inclined gear. A housing for storing toner particles for developing a latent image carried on the image carrier, and (b) a center of a surface facing the opening that communicates the inside and outside of the housing for carrying the toner particles. At least one groove for moving the toner particles to the part has a predetermined inclination with respect to the axial direction and is formed in a spiral shape at an equal pitch in the axial direction. A toner particle carrying roller that moves in a direction opposite to the predetermined direction; and (c) an end seal that is in contact with the peripheral surface at both ends of the toner particle carrying roller and seals the gap with the housing. , A developing device, provided with a with a (B) The image forming system comprising the image forming apparatus, for forming an image using a developing device can be realized.

=== Overview of Image Forming Apparatus ===
A configuration example of a laser beam printer (hereinafter also referred to as a printer) 10 as an example of an image forming apparatus that forms an image using a developing device as a developing apparatus according to the present embodiment, with reference to FIGS. An operation example will be described. FIG. 1 is a diagram showing main components constituting the printer 10, and FIG. 2 is a diagram for explaining a configuration of a control unit provided in the printer 10. In FIG. 1, the vertical direction is indicated by arrows. For example, the paper feed tray 92 is disposed at the lower part of the printer 10, and the fixing unit 90 is disposed at the upper part of the printer 10.

<Configuration of Printer 10>
As shown in FIG. 1, the printer 10 includes a charging unit 30, an exposure unit 40, a developing device holding unit 50, and a primary transfer unit along the rotation direction of a photoconductor 20 as an example of an image carrier that carries a latent image. 60, an intermediate transfer body 70, and a cleaning unit 75, and further controls a secondary transfer unit 80, a fixing unit 90, a display unit 95 formed of a liquid crystal panel as a means for notifying a user, and these units. It has a control unit 100 that controls the operation as a printer.

  The photoreceptor 20 has a cylindrical conductive substrate and a photosensitive layer formed on the outer peripheral surface thereof, and is rotatable around a central axis. In the present embodiment, the photoreceptor 20 is indicated by an arrow in FIG. Rotate clockwise.

  The charging unit 30 is a device for charging the photoconductor 20, and the exposure unit 40 is a device for forming a latent image on the photoconductor 20 charged by irradiating a laser. The exposure unit 40 includes a semiconductor laser for emitting a laser beam as light, a polygon mirror unit that rotates a polygonal polygon mirror, and a plurality of types of lenses such as an F-θ lens. Based on an image signal input from a host computer (not shown) such as a word processor, the modulated photoconductor 20 is irradiated with a modulated laser beam.

  The developing device holding unit 50 converts the latent image formed on the photoreceptor 20 into toner particles (hereinafter also referred to as toner) T accommodated in developing devices 51, 52, 53, and 54 as an example of a developing device, that is, The black (K) toner contained in the black developing device 51, the magenta (M) toner contained in the magenta developing device 52, the cyan (C) toner contained in the cyan developing device 53, and the yellow developing device 54. This is an apparatus for developing using yellow (Y) toner.

  In the present embodiment, the developing device holding unit 50 is capable of moving the positions of the four developing devices 51, 52, 53, and 54 by rotating. That is, the developing device holding unit 50 holds the four developing devices 51, 52, 53, and 54 by the four attaching / detaching portions 50a, 50b, 50c, and 50d, and the four developing devices 51, 52, and 53 are provided. , 54 can rotate around the central axis 50e while maintaining their relative positions. Each time the photosensitive member 20 rotates once, one of the four developing devices 51, 52, 53, 54 is selectively opposed to the photosensitive member 20, and the opposed developing devices 51, 52, 53, 54, The latent images formed on the photoreceptor 20 are sequentially developed with the toner contained in the toner 54. Details of each developing device will be described later.

  The primary transfer unit 60 is a device for transferring a single color toner image formed on the photoconductor 20 to the intermediate transfer body 70. When four color toners are sequentially transferred in a superimposed manner, the full color toner is transferred to the intermediate transfer body 70. An image is formed. The intermediate transfer member 70 is an endless belt, and is driven to rotate at substantially the same peripheral speed as the photosensitive member 20. The secondary transfer unit 80 is a device for transferring a single color toner image or a full color toner image formed on the intermediate transfer body 70 to a recording medium such as paper, film, or cloth.

  The fixing unit 90 is a device for fusing a single color toner image or a full color toner image transferred onto a recording medium onto a recording medium such as paper to form a permanent image. The cleaning unit 75 is provided between the primary transfer unit 60 and the charging unit 30 and has a rubber cleaning blade 76 that is in contact with the surface of the photoconductor 20. The cleaning unit 75 is disposed on the intermediate transfer body 70 by the primary transfer unit 60. After the toner image is transferred, the toner T remaining on the photoconductor 20 is scraped off and removed by the cleaning blade 76.

  As shown in FIG. 2, the control unit 100 includes a main controller 101 and a unit controller 102. An image signal is input to the main controller 101, and the unit controller 102 responds to an instruction based on the image signal. The unit is controlled to form an image.

  The main controller 101 is connected to a host computer via an interface 112, and includes an image memory 113 for storing an image signal input from the host computer, a CPU 111 for controlling the entire printer 10, and the like.

  The unit controller 102 includes a CPU 120, a memory 116 such as a RAM and a ROM, and units of the apparatus main body (charging unit 30, exposure unit 40, primary transfer unit 60, cleaning unit 75, secondary transfer unit 80, fixing unit 90, The display unit 95) and each drive control circuit for driving and controlling the developing device holding unit 50 are controlled, and each unit is controlled based on a signal input from the main controller 101.

<Operation of Printer 10>
Next, the operation of the printer 10 will be described with reference to other components.
First, when an image signal from a host computer (not shown) is input to the main controller 101 of the printer 10 via the interface (I / F) 112, the photosensitive device is controlled by the unit controller 102 based on a command from the main controller 101. The developing roller 510 and the intermediate transfer member 70 provided on the body 20, the developing devices 51, 52, 53, and 54 rotate. The photoconductor 20 is charged by the charging unit 30 at the charging position while rotating.

The charged region of the photoconductor 20 reaches the exposure position as the photoconductor 20 rotates, and a latent image corresponding to image information of the first color, for example, yellow Y, is formed by the exposure unit 40. At this time, the developing device holding unit 50 positions the yellow developing device 54 containing yellow (Y) toner at a developing position facing the photoconductor 20.
The latent image formed on the photoconductor 20 reaches the development position as the photoconductor 20 rotates, and is developed with yellow toner by the yellow developing device 54. As a result, a yellow toner image is formed on the photoreceptor 20.
The yellow toner image formed on the photoconductor 20 reaches the primary transfer position as the photoconductor 20 rotates, and is transferred to the intermediate transfer body 70 by the primary transfer unit 60. At this time, a primary transfer voltage having a polarity opposite to the charging polarity of the toner is applied to the primary transfer unit 60. During this time, the secondary transfer unit 80 is separated from the intermediate transfer member 70.

By repeating the above processing for the second color, the third color, and the fourth color, the four color toner images corresponding to the respective image signals are transferred onto the intermediate transfer body 70 in an overlapping manner. . As a result, a full color toner image is formed on the intermediate transfer member 70.
The full-color toner image formed on the intermediate transfer body 70 reaches the secondary transfer position as the intermediate transfer body 70 rotates, and is transferred to a recording sheet as a recording medium by the secondary transfer unit 80. The recording paper is conveyed from the paper feed tray 92 to the secondary transfer unit 80 via the paper feed roller 94 and the registration roller 96. When performing the transfer operation, the secondary transfer unit 80 is pressed against the intermediate transfer body 70 and a secondary transfer voltage is applied.
The full-color toner image transferred to the recording paper is heated and pressurized by the fixing unit 90 and fused to the recording paper. On the other hand, after the primary transfer position has elapsed, the toner remaining on the surface of the photoreceptor 20 is scraped off by the cleaning blade 76 to prepare for charging for forming the next latent image. The toner scraped off is collected in a waste toner container.

=== Overview of Developer ===
Next, a configuration example of the developing device will be described with reference to FIGS. FIG. 3 is a perspective view of the yellow developing device. FIG. 4 is a cross-sectional view showing the main components of the yellow developing device. FIG. 5 is a perspective view showing the developing device with the developing roller removed. The cross-sectional view shown in FIG. 4 is a view showing a cross section obtained by cutting the yellow developing device along a plane perpendicular to the longitudinal direction shown in FIG. 4, the vertical direction is indicated by arrows as in FIG. 1. For example, the central axis of the developing roller 510 is below the central axis of the photoconductor 20. Further, in FIG. 4, the yellow developing device 54 is shown in a state where the yellow developing device 54 is located at a developing position facing the photoconductor 20.

  The developing device holding unit 50 includes a black developing device 51 containing black (K) toner, a magenta developing device 52 containing magenta (M) toner, a cyan developing device 53 containing cyan (C) toner, and yellow. (Y) Although the yellow developing unit 54 containing toner is provided, the configuration of each developing unit is the same, so the yellow developing unit 54 will be described below.

<Configuration of Yellow Developer 54>
The yellow developing unit 54 includes a housing 540 that accommodates toner T, a developing roller 510 as an example of a toner particle carrying roller for carrying toner, a toner supply roller 550 for supplying toner to the developing roller 510, and a developing roller 510. A regulating blade 560 as an example of a layer thickness regulating member for regulating the layer thickness of the toner carried on the toner, an upper seal 520 for sealing the upper gap between the housing 540 and the developing roller 510, and development with the housing 540 An end seal 527 for sealing a gap on the end side with the roller 510 is provided.

  The housing 540 is manufactured by welding an integrally molded resin upper housing portion 542 and lower housing portion 544, and a toner storage portion serving as a storage portion for storing the toner T therein. 530 is formed. The toner storage portion 530 is divided into two toner storage portions, that is, a first toner storage portion 530a and a second toner, by a partition wall 545 for partitioning the toner T that protrudes inwardly (in the vertical direction in FIG. 4) from the inner wall. It is divided into the accommodating portion 530b.

  The upper portions of the first toner storage portion 530a and the second toner storage portion 530b communicate with each other. In the state shown in FIG. 4, the movement of the toner T is restricted by the partition wall 545. However, when the developing device holding unit 50 rotates, the toner stored in the first toner storage portion 530a and the second toner storage portion 530b is temporarily moved to the upper communicating side of the developing position. When the toner is collected and returns to the state shown in FIG. 4, the toners are mixed and returned to the first toner storage portion 530a and the second toner storage portion 530b. That is, the toner T in the developing device is agitated by the rotation of the developing device holding unit 50. For this reason, in this embodiment, the stirring member is not provided in the toner storage portion 530, but a stirring member for stirring the toner T stored in the toner storage portion 530 may be provided. As shown in FIG. 4, the housing 540 has an opening 572 in the lower portion, and a developing roller 510 described later is provided so as to face the opening 572.

  The toner supply roller 550 includes an elastic roller portion 550a formed of, for example, urethane foam, and a shaft body 550b that serves as a rotation center of the roller portion 550a. The toner supply roller 550 is supported by the housing 540 at both ends of the shaft body 550b, so that the toner supply roller 550 is rotatably supported around the shaft body 550b. The roller portion 550 a is accommodated in the first toner accommodating portion 530 a (inside the housing 540) of the housing 540 and supplies the toner T accommodated in the first toner accommodating portion 530 a to the developing roller 510. The toner supply roller 550 is provided vertically below the first toner storage portion 530a. The toner T accommodated in the first toner accommodating portion 530a is supplied to the developing roller 510 by the toner supply roller 550 below the first toner accommodating portion 530a. Further, the toner supply roller 550 peels off the excess toner T remaining on the developing roller 510 after development from the developing roller 510.

  The toner supply roller 550 and the developing roller 510 are assembled to the housing 540 while being pressed against each other. Therefore, the roller portion 550a of the toner supply roller 550 is in contact with the developing roller 510 in an elastically deformed state. The toner supply roller 550 rotates in a direction (clockwise in FIG. 4) opposite to the rotation direction of the developing roller 510 (counterclockwise in FIG. 4). The shaft body 550b is below the rotation center axis of the developing roller 510.

  The developing roller 510 carries the toner T and conveys it to a developing position facing the photoconductor 20. The developing roller 510 is made of metal and is made of an aluminum alloy such as 5056 aluminum alloy or 6063 aluminum alloy, or an iron alloy such as STKM, and is subjected to nickel plating, chrome plating, or the like as necessary. May be. On the surface of the developing roller 510, a spiral groove is provided at the center in the axial direction of the developing roller 510. The surface shape of the developing roller 510 will be described in detail later.

  Further, as shown in FIG. 3, the developing roller 510 is supported at both ends in the longitudinal direction. A driving gear 516 for transmitting power from a motor (not shown) as a driving source and rotating the developing roller 510 is provided at one end of the developing roller 510. The drive gear 516 is an inclined gear, and when the drive gear 516 rotates, a force along the axial direction is urged to the developing roller 510 so that the drive gear 516 is not provided. Moved. As shown in FIG. 4, the developing roller 510 rotates in a direction (counterclockwise in FIG. 4) opposite to the rotation direction of the photoconductor 20 (clockwise in FIG. 4). The central axis is below the central axis of the photoconductor 20.

  As shown in FIG. 4, there is a gap between the developing roller 510 and the photoconductor 20 in a state where the yellow developing device 54 faces the photoconductor 20. That is, the yellow developing device 54 develops the latent image formed on the photoconductor 20 in a non-contact state. When developing the latent image formed on the photoconductor 20, an alternating electric field is formed between the developing roller 510 and the photoconductor 20.

  The regulating blade 560 applies a charge to the toner T carried on the developing roller 510 and regulates the layer thickness of the toner T carried on the developing roller 510. The regulation blade 560 has a rubber part 560a and a rubber support part 560b. The rubber part 560a is made of silicon rubber, urethane rubber or the like, and the rubber support part 560b is a thin plate having spring properties such as phosphor bronze or stainless steel. The rubber portion 560a is supported on the short side of the rubber support portion 560b along the longitudinal direction of the rubber support portion 560b, and the other end side of the rubber support portion 560b is supported by the blade support metal plate 562. In this state, it is attached to the housing 540 via the blade support sheet metal 562. Further, a blade back member 570 made of malt plane or the like is provided on the side opposite to the developing roller 510 side of the regulating blade 560.

  Here, the rubber portion 560 a is pressed from the central portion of the developing roller 510 to both ends by the elastic force due to the bending of the rubber support portion 560 b. Further, the blade back member 570 prevents the toner T from entering between the rubber support portion 560b and the housing 540, stabilizes the elastic force due to the bending of the rubber support portion 560b, and provides rubber from the back of the rubber portion 560a. The rubber portion 560 a is pressed against the developing roller 510 by urging the portion 560 a toward the developing roller 510. Therefore, the blade back member 570 improves the uniform contact property of the rubber portion 560a to the developing roller 510.

  The end of the regulating blade 560 opposite to the side supported by the blade support metal plate 562, that is, the tip is not in contact with the developing roller 510, and a portion away from the tip by a predetermined distance is the developing roller. 510 is in contact with a width. In other words, the regulating blade 560 is not in contact with the developing roller 510 at the edge, but is in contact with the antinode on the flat surface of the rubber portion 560a. The regulating blade 560 is disposed so that the tip thereof faces the upstream side in the rotation direction of the developing roller 510, and is in a so-called counter contact. The contact position where the regulating blade 560 contacts the developing roller 510 is below the central axis of the developing roller 510 and below the central axis of the toner supply roller 550.

  The rubber support portion 560b is longer than the rubber portion 560a in the axial direction of the developing roller 510, and extends outward from both ends of the rubber portion 560a. An end seal 527 made of, for example, a nonwoven fabric having a thickness thicker than that of the rubber portion 560a is attached to the same surface as the rubber portion and 560a at the extended portion of the rubber support portion 560b. At this time, the end surface of the rubber portion 560 a in the axial direction is in contact with the side surface of the end seal 527.

  The end seal 527 is made of, for example, elastic foamed urethane or the like, and is provided so as to come into contact with both ends of the surface of the developing roller 510 where no groove is provided when the developing roller 510 is attached. The housing 540 is provided with ribs 540a as positioning protrusions along which the end seal 527 is positioned. The rib 540a is provided perpendicular to the axis of the developing roller 510, and the end seal 527 is attached so that the outer end surface of the end seal 527 is in contact with the inner surface 540b of the rib 540a in the axial direction. . Further, the end seal 527 extends sufficiently longer than the tip of the rubber portion 560 a of the regulating blade 560. When the regulating blade 560 is attached to the housing 540, the end seal 527 is placed along a portion of the housing 540 formed so as to face the outer peripheral surface of the developing roller 510, and closes the gap between the housing 540 and the developing roller 510. .

  The upper seal 520 prevents the toner T in the yellow developing device 54 from leaking out of the device, and collects the toner T on the developing roller 510 that has passed through the developing position into the developing device without being scraped off. The upper seal 520 is a seal made of a polyethylene film or the like. The upper seal 520 is supported by a seal support sheet metal 522 and is attached to the housing 540 via the seal support sheet metal 522. A seal urging member 524 made of malt plain or the like is provided on the opposite side of the upper seal 520 from the developing roller 510 side. The upper seal 520 is developed by the elastic force of the seal urging member 524. 510 is pressed. The contact position at which the upper seal 520 contacts the developing roller 510 is above the central axis of the developing roller 510.

<Operation of Yellow Developer 54>
In the yellow developing device 54 configured as described above, the toner supply roller 550 supplies the toner T accommodated in the toner accommodating portion 530 to the developing roller 510. The toner T supplied to the developing roller 510 reaches the contact position of the regulating blade 560 as the developing roller 510 rotates, and when passing through the contact position, an electric charge is applied and the layer thickness is regulated. Is done.

  The charged toner T on the developing roller 510 reaches a developing position facing the photoconductor 20 by further rotation of the developing roller 510, and a latent image formed on the photoconductor 20 under an alternating electric field at the developing position. For development. The toner T on the developing roller 510 that has passed the developing position by further rotation of the developing roller 510 passes through the upper seal 520 and is collected in the developing device without being scraped off by the upper seal 520. Further, the toner T still remaining on the developing roller 510 can be peeled off by the toner supply roller 550.

=== Surface shape of developing roller ===
In the drawing showing the surface of the developing roller 510 used in the description of the present embodiment, the groove on the surface of the developing roller 510 is shown as a straight line for convenience, but the groove is formed in a spiral shape. It is formed to look like a curve.

<First Embodiment>
FIG. 6 is a conceptual diagram for explaining the surface shape of the developing roller according to the first embodiment. FIG. 7 is a view taken in the direction of arrow A in FIG. 6 showing the arrangement of the developing roller and the regulating blade. FIG. 8 is a cross-sectional view for explaining a cross section when the developing roller according to the first embodiment is cut along a plane passing through an axis.

  The developing roller 510 is provided with a concavo-convex portion for supporting toner particles in the central portion 510a in the axial direction, and both end portions 510b have smooth peripheral surfaces so that end seals 527 are in close contact with each other.

  As shown in FIG. 6, in the central portion 510 a of the developing roller 510 in this embodiment, a spiral groove 511 that is inclined with respect to the axial direction and the circumferential direction of the developing roller 510 and is formed at an equal pitch in the axial direction. Is formed. The groove 511 is formed in a spiral shape so as to form an angle of 45 ° counterclockwise with the axis of the developing roller 510, and moves away from the drive gear 516 when following the rotation direction of the developing roller 510. It is formed in a spiral shape inclined in the direction.

  As shown in FIG. 8, the groove portions 511 are formed at an interval of about 113 μm in the axial direction of the developing roller 510, and the angle of the inclined portion 511d extending from the top surface 512a of the convex portion 512 to the bottom surface 511c of the groove portion 511. Is formed such that the intersecting angle α of the virtual plane obtained by extending the two inclined surfaces forming the groove 511 in the direction of the axis C is 90 °.

  Further, the depth of the groove portion 511, that is, the distance from the top surface 512a of the convex portion 512 to the bottom surface 511c of the groove portion 511 is formed to be constant at about 7 μm. Here, the volume average particle diameter of the toner is about 5 to 10 μm, and the depth of the groove 511 is set to be not more than twice the volume average particle diameter of the toner.

  Such a developing roller 510 is formed by rolling. FIG. 9 is a diagram for explaining how the developing roller is formed by rolling. FIG. 10 is a diagram illustrating a procedure for forming the developing roller.

The developing roller 510 is formed from a cylindrical hollow material.
The cylindrical material is first cut to a length that can form a central portion 510a for carrying toner as the developing roller 510 and an end portion 510b with which the end seal 527 abuts, and the cylindrical member 515 is cut out. (S001). In the cylindrical member 515, a step portion 510c (FIG. 8) for fitting a flange 513 having the shaft of the developing roller 510 is formed on the inner peripheral portion of both end portions by cutting (S002). Here, the flange 513 includes a disk-shaped flange main body 513a having a diameter that is press-fitted into the formed stepped portion 510c, and a shaft portion 513b that protrudes perpendicularly to the disk surface from the center thereof. ing.

  Next, the flange 513 having the shaft portion 513b is fitted into the cylindrical member 515 having the step portion 510c formed inside the both end portions so that the shaft portion 513b protrudes outward of the cylindrical member (S003). .

  Thereafter, the cylindrical member 515 in which the flange 513 is fitted is supported by the shaft portions 513b at both ends and rotated around the shaft, and the outer peripheral surface of the cylindrical member 515 is slightly cut over the entire circumference, thereby The surface of the cylindrical member 515 is polished so that the entire region is concentric with the shaft, that is, at a certain distance from the shaft, so that the non-rolled developing roller 509 is formed (S004).

  The cylindrical member 515 whose surface is polished has a groove 511 formed on the surface by rolling with an apparatus having a die 900 as a processing tool as shown in FIG. 9 (S005). The rolling device rotates the die 900 disposed in a position facing the workpiece (here, the non-rolling processing developing roller 509) in a predetermined direction, presses the die 900 against the non-rolling processing developing roller 509, The roll developing roller 509 is conveyed in the axial direction while rotating in the opposite direction to the die 900. The die 900 is provided with a blade 900a for forming the groove 511 described above. Here, the part where the die 900 is brought into contact with the surface of the non-rolling processing developing roller 509 is the blade 900a. However, the rolling process does not actively cut the work, but the work is crushed by the pressing force. Acts to form a depression. Further, during this rolling, the non-rolled developing roller 509 is not contacted with the die 900 at both ends 510b, leaving a smooth surface without unevenness at both ends 510b. deep. That is, since the top surface 512a of the convex portion 512 where the die 900 did not contact with the central portion 510a of the developing roller 510 and the both end portions 510b that are not to be processed by rolling are still cut, from the axis C. Located equidistant. The surface 510d of the developing roller 510 is substantially covered with the bottom surface 511c of the groove 511 that is recessed by the contact of the die 900 and the non-processed surface that the die 900 does not contact.

  The developing roller 510 formed by rolling may be subjected to, for example, electroless Ni—P plating, electroplating, or hard chrome plating, if necessary.

  As shown in FIG. 7, a transmission gear (not shown) is connected to the drive gear 516 from the front side of the paper surface in FIG. 6. For this reason, when the developing roller rotates as indicated by the arrow in FIG. 7, power is transmitted by the inclined drive gear 516, so that the developing roller 510 is opposed to the drive gear 516 along the axial direction by this power. Will be urged in the direction of.

  FIG. 11 is a diagram for explaining the state of the end seal when the developing roller moves along the axial direction as the drive gear rotates. FIG. 11A is a diagram illustrating a state where the drive gear is stopped. FIG. 11B is a diagram illustrating a state in which the developing roller has moved along with the rotation of the drive gear. As shown in FIG. 11A, in the case of the present embodiment, in a state where the driving gear is not rotating, the end seals 527 are pressed to both end portions of the developing roller 510 where the groove portions 511 are not formed. At this time, the end seals 527 are arranged along the ribs 540 a provided on the outer sides in the axial direction of the end seals 527, respectively, and the back side of the surface that contacts the developing roller 510 is adhered to the housing 540. When the inclined drive gear 516 rotates in this state, the developing roller 510 moves in the opposite direction to the drive gear 516 along the axial direction. As the developing roller 510 moves, an end seal (hereinafter referred to as a non-driving side end seal) 527a provided at the end opposite to the drive gear 516, as shown in FIG. A force that moves in the direction opposite to that of the drive gear 516 is applied. However, the non-driving side end seal 527a does not move because the side opposite to the driving gear 516 is restricted by the rib 540a, but is crushed in the axial direction because of elastic deformation. The crushed counter-driving side end seal 527a may be deteriorated in sealing performance due to wrinkling or curling on the contact surface with the developing roller 510. In addition, when the groove 511 formed in the developing roller 510 is close to the counter driving side end seal 527a in a state where the developing roller 510 is not rotating, a part of the groove is the counter driving side end. There is a possibility that the developing roller 510 moves to a position facing the seal 527a and the sealing performance by the counter driving side end seal 527a is lowered. That is, at the end on the side where the developing roller 510 is moved by the rotation of the driving gear 516, the central portion 510a on which the toner particles are carried by the developing roller 510 approaches the outside of the housing 540, and the non-driving side end seal The sealing property of 527a is also lowered, and the toner particles are likely to leak.

  Therefore, in the present embodiment, a groove having an inclination with respect to the axial direction is formed in the central portion 510a of the developing roller 510 so as to move the toner particles toward the drive gear 516 in the axial direction.

  More specifically, the regulating blade 560 is in contact with the developing roller 510 below the axis of the developing roller 510. Therefore, the toner particles supplied from the toner supply roller 550 on the upper side of the regulating blade 560 and on the left side of the developing roller 510 in FIG. 7 reach the position of the regulating blade 560 as the developing roller 510 rotates. The toner particles that have reached the position of the regulating blade 560 are regulated in layer thickness by the regulating blade 560, and are rolled between the developing roller 510 and the regulating blade 560 while moving upward, that is, on the opposite side to the rotational direction. Will be moved.

  When moving in the direction opposite to the rotation direction of the developing roller 510, the toner particles entering the groove 511 are moved along the groove 511 in the direction opposite to the rotation of the developing roller 510. That is, the toner particles are moved toward the drive gear 516 along the axial direction. This is a direction opposite to the direction in which the developing roller 510 is urged by power when the developing roller 510 rotates. Therefore, when the developing roller 510 rotates, the toner particles are moved more to the drive gear 516 side than the side opposite to the drive gear 516 in the axial direction.

  Therefore, when the developing roller 510 is urged and moved in the direction opposite to the driving gear 516 by power, the end of the central portion 510a of the developing roller 510 provided with the groove portion 511 is close to the non-driving side end seal 527a. Even so, the toner particles are moved more in the direction of the drive gear 516, so that the toner particles overflow on the side opposite to the driving side end seal 527 a close to the end of the central portion 510 a of the developing roller 510, or are counteracted by the toner particles. The driving side end seal 527a is not excessively pressed. For this reason, even if the developing roller 510 is moved in the direction opposite to the driving gear 516 by power, it is possible to prevent the toner particles from leaking out of the developing devices 51, 52, 53, and 54.

  In the first embodiment, the inclination angle of the groove portion 511 with respect to the axial direction is set to 45 °. However, the present invention is not limited to this, and if the inclination angle with respect to the axial direction is reduced, the toner particles can be moved more to the drive gear 516 side. Is possible.

  FIG. 12 is a diagram for explaining a first modification of the first embodiment. In the first embodiment, the depth of the groove portion 511 is constant. However, as shown in FIG. 12, the depth of the groove portion 511 is shallower by the anti-drive gear 516 and deeper on the drive gear 516 side. It is possible to move further toward the drive gear 516 side.

  FIG. 13 is a diagram for explaining a second modification of the first embodiment. In the first embodiment, the width of the groove portion 511 is also constant, but as shown in FIG. 13, the width of the groove portion 511 is narrow on the counter drive gear 516 side and wide on the drive gear 516 side, thereby driving the toner. It is possible to move further to the gear 516 side.

Second Embodiment
FIG. 14 is a conceptual diagram for explaining the surface shape of the developing roller according to the second embodiment.

  The developing roller 510 is provided with a concavo-convex portion for supporting toner particles in the central portion 510a in the axial direction, and both end portions 510b have smooth peripheral surfaces so that end seals 527 are in close contact with each other.

  As shown in FIG. 14, in the central portion 510 a of the developing roller 510 in this embodiment, a spiral groove 511 that is inclined with respect to the axial direction and the circumferential direction of the developing roller 510 and is formed at an equal pitch in the axial direction. Is formed. The groove portion 511 is formed in two types with different inclination angles with respect to the axial direction and the circumferential direction of the developing roller 510. The two types of groove portions 511 intersect each other to form a lattice shape, and the top surface 512a of the convex portion 512 surrounded by the two types of groove portions 511 is formed in a substantially parallelogram shape.

  That is, one of the two types of groove portions 511 is formed in a spiral shape so as to form an angle of 45 ° counterclockwise with the shaft of the developing roller 510, and the other second groove portion 511a. The groove 511b is formed in a spiral shape so as to form an angle of 30 ° clockwise with the axis of the developing roller 510. For this reason, the angle at which the first groove portion 511a and the second groove portion 511b intersect is 105 °.

  The two types of groove portions 511 each have a width of 80 μm, and are formed at intervals of 80 μm from adjacent groove portions, as shown in FIG. 14, and from the top surface 512a of the convex portion 512 to the bottom surface of the groove portion 511. The angle of the inclined portion 511d reaching 511c is formed so that the intersecting angle α of the virtual plane obtained by extending the two inclined surfaces forming the groove portion 511 in the direction of the axis C is 90 °, like the groove portion of the first embodiment. Has been.

  Further, the depth of the groove portion 511, that is, the distance from the top surface 512a of the convex portion 512 to the bottom surface 511c of the groove portion 511 is formed to be constant at about 7 μm. Here, the volume average particle diameter of the toner is about 5 to 10 μm, and the depth of the groove 511 is set to be not more than twice the volume average particle diameter of the toner.

  Such a developing roller 510 is formed by rolling. FIG. 15 is a diagram for explaining how the developing roller is formed by rolling. The developing roller manufacturing method according to the second embodiment is almost the same as the developing roller manufacturing method according to the first embodiment. However, as shown in FIG. It is different in use. That is, a cylinder whose surface is polished is obtained by pressing the two types of dies 900 against the unrolled developing roller 509 and conveying the non-rolled developing roller 509 in the axial direction while rotating in the opposite direction to the die 900. Two types of grooves 511 a and 511 b are formed on the surface of the member 515. Further, during this rolling, the non-rolled developing roller 509 is not contacted with the die 900 at both ends 510b, leaving a smooth surface without unevenness at both ends 510b. deep.

  In the developing devices 51, 52, 53, and 54 having such a developing roller 510, the toner particles supplied from the toner supply roller 550 are also removed from the regulating blade 560 as the developing roller 510 rotates, as in the above embodiment. The toner particles reaching the position and the position of the regulating blade 560 are regulated in layer thickness by the regulating blade 560 and rolled upward between the developing roller 510 and the regulating blade 560, that is, in the rotational direction. And moved to the opposite side.

  When the developing roller 510 is moved in the direction opposite to the rotation direction, the toner particles entering the groove 511 are moved along the groove 511. And when it has the two groove parts 511a and 511b from which an angle mutually differs like the developing roller 510 of this embodiment, the one where an inclination angle is smaller in the surface area of the developing roller 510 moved by a predetermined rotation angle. The ratio occupied by the grooves 511 increases, and the movement efficiency of the toner particles increases.

  Therefore, in this embodiment, the inclination angle of the second groove portion 511b provided so that the toner particles moved to the opposite side of the rotation direction with the rotation of the developing roller 510 are directed to the drive gear 516 side is set to 30 °. The inclination angle of the first groove portion 511a provided so as to face the side opposite to the drive gear 516 is 45 °.

  When the developing roller 510 provided with such two grooves 511a and 511b is used, more toner particles can be moved in a direction opposite to the moving direction than the moving direction in which the developing roller 510 is moved by the drive gear 516. Is possible. Therefore, even if the developing roller 510 is moved in the opposite direction to the drive gear 516 by power, it is possible to prevent the toner particles from leaking out of the developing devices 51, 52, 53, and 54.

<Third Embodiment>
FIG. 16 is a conceptual diagram for explaining the surface shape of the developing roller according to the third embodiment.
The developing roller 510 is provided with a concavo-convex portion for supporting toner particles in the central portion 510a in the axial direction, and both end portions 510b have smooth peripheral surfaces so that end seals 527 are in close contact with each other. In the description of the present embodiment, parts that are the same as in the second embodiment are given the same reference numerals, and descriptions thereof are omitted.

  As shown in FIG. 16, in the central portion 510 a of the developing roller 510 in this embodiment, a spiral groove 511 that is inclined with respect to the axial direction and the circumferential direction of the developing roller 510 and is formed at an equal pitch in the axial direction. Two are formed. The two groove portions 511 are formed so that the inclination angle of the developing roller 510 with respect to the axial direction and the circumferential direction is 45 °. That is, the two groove portions 511 intersect with each other to form a lattice shape, and the top surface 512a of the convex portion 512 surrounded by the two groove portions 511 is formed to be substantially square. Moreover, the 1st groove part 511a and the 2nd groove part 511b are formed so that one may follow a circumferential direction among the two diagonal lines which the square of the top surface 512a has. Further, in the developing roller 510 included in the developing devices 51, 52, 53, and 54 of the third embodiment, the width of the second groove 511b is wider than the width of the first groove 511a, for example, the width of the first groove 511a. Is 75 μm, and the width of the second groove 511b is 85 μm. Further, the angle of the inclined portion 511d is such that the intersecting angle α of the virtual plane obtained by extending the two inclined surfaces forming the groove 511 in the direction of the axis C is 90 °, and the depth of the groove 511 is constant at about 7 μm. It is formed as follows.

  Similar to the second embodiment, such a developing roller 510 is also formed by rolling using two types of dice 900, but the two types of dice 900 have dice 900 in which grooves 511 having different widths are formed. It is different from the second embodiment in that it is used.

  In the developing devices 51, 52, 53, and 54 having such a developing roller 510, when the toner particles entering the groove 511 are moved in the direction opposite to the rotation direction of the developing roller 510, it is natural. The groove portion 511b having the wider width of the groove portion 511 has a higher proportion of the groove portion 511 occupying the surface area of the developing roller 510 moved at a predetermined rotation angle.

  Therefore, in the third embodiment, the width of the second groove portion 511b provided so that the toner particles moved to the opposite side of the rotation direction with the rotation of the developing roller 510 are directed to the drive gear 516 side is set to 85 μm. The width of the first groove portion 511a provided so as to face the side opposite to the drive gear 516 is 75 μm. When the developing roller 510 provided with such two grooves 511a and 511b is used, more toner particles can be moved in a direction opposite to the moving direction than the moving direction in which the developing roller 510 is moved by the drive gear 516. Is possible. Therefore, even if the developing roller 510 is moved in the opposite direction to the drive gear 516 by power, it is possible to prevent the toner particles from leaking out of the developing devices 51, 52, 53, and 54.

<Fourth embodiment>
FIG. 17 is a conceptual diagram for explaining the surface shape of the developing roller according to the fourth embodiment. 18 is a cross-sectional view taken along line AA in FIG.

  The developing roller 510 is provided with a concavo-convex portion for supporting toner particles in the central portion 510a in the axial direction, and both end portions 510b have smooth peripheral surfaces so that end seals 527 are in close contact with each other. In the description of the fourth embodiment, parts that are the same as in the above embodiment are given the same reference numerals, and descriptions thereof are omitted.

  As shown in FIG. 17, a spiral groove formed in the central portion 510a of the developing roller 510 in the fourth embodiment is inclined with respect to the axial direction and the circumferential direction of the developing roller 510 and is formed at an equal pitch in the axial direction. Two 511 are formed. The two groove portions 511 are formed so that the inclination angle of the developing roller 510 with respect to the axial direction and the circumferential direction is 45 °. That is, the two groove portions 511 intersect with each other to form a lattice shape, and the top surface 512a of the convex portion 512 surrounded by the two groove portions 511 is formed to be substantially square. Moreover, the 1st groove part 511a and the 2nd groove part 511b are formed so that one may follow a circumferential direction among the two diagonal lines which the square of the top surface 512a has. Further, in the developing roller 510 included in the developing devices 51, 52, 53, and 54 of the fourth embodiment, the depth of the second groove 511b is deeper than the depth of the first groove 511a, for example, the first groove 511a. The depth is 7 μm, and the depth of the second groove portion 511b is 8 μm. The angle of the inclined portion 511d is such that the intersecting angle α of the virtual plane obtained by extending the two inclined surfaces forming the groove portion 511 in the direction of the axis C is 90 °, and the width of the groove portion 511 is constant at about 80 μm. Is formed.

  Such a developing roller 510 is formed by rolling using two types of dies 900. The depths of the two types of grooves 511 to be formed are made different by making the pressing force when the two dies are pressed against the non-rolling processing developing roller 509 different. That is, the die 900 that forms the second groove 511b has a stronger pressing force than the die 900 that forms the first groove 511a.

  In the developing devices 51, 52, 53, and 54 having such a developing roller 510, when the toner particles entering the groove 511 are moved in the direction opposite to the rotation direction of the developing roller 510, it is natural. The groove portion 511b having a deeper groove portion 511 has a larger amount of toner particles per unit area. Therefore, the amount of toner particles moved at a predetermined rotation angle increases, and the toner particle movement efficiency increases. .

  For this reason, in the fourth embodiment, the depth of the second groove 511b provided so that the toner particles moved to the opposite side of the rotation direction with the rotation of the developing roller 510 are directed to the drive gear 516 side is set to 8 μm. The depth of the first groove portion 511a provided so as to face the side opposite to the drive gear 516 is 7 μm. When the developing roller 510 provided with such two grooves 511a and 511b is used, more toner particles can be moved in a direction opposite to the moving direction than the moving direction in which the developing roller 510 is moved by the drive gear 516. Is possible. Therefore, even if the developing roller 510 is moved in the direction opposite to the driving gear 516 by power, it is possible to prevent the toner from leaking out of the developing devices 51, 52, 53, and 54.

<Fifth Embodiment>
FIG. 19 is a conceptual diagram for explaining the surface shape of the developing roller according to the fifth embodiment.

  The developing roller 510 is provided with a concavo-convex portion for supporting toner particles in the central portion 510a in the axial direction, and both end portions 510b have smooth peripheral surfaces so that end seals 527 are in close contact with each other. In the description of the present embodiment, parts that are the same as those in the above embodiment are given the same reference numerals, and descriptions thereof are omitted.

  As shown in FIG. 19, in the central portion 510 a of the developing roller 510 in this embodiment, a spiral groove 511 that is inclined with respect to the axial direction and the circumferential direction of the developing roller 510 and is formed at an equal pitch in the axial direction. Two are formed. The two groove portions 511 are formed so that the inclination angle of the developing roller 510 with respect to the axial direction and the circumferential direction is 45 °. That is, the two groove portions 511 intersect with each other to form a lattice shape, and the top surface 512a of the convex portion 512 surrounded by the two groove portions 511 is formed to be substantially square. Further, the first groove portion and the second groove portion are formed so that one of the two diagonal lines of the square of the top surface 512a is along the circumferential direction. In addition, the angle of the inclined portion 511d is such that the intersecting angle α of the virtual plane obtained by extending the two inclined surfaces forming the groove 511 in the direction of the axis C is 90 °, the width of the groove 511 is about 80 μm, and the depth of the groove Is formed to be constant at 7 μm.

  In the developing roller 510 of the fifth embodiment, the areas where the first groove portion 511a and the second groove portion 511b are formed are different. That is, as shown in FIG. 19, the second groove portion 511b provided so that the toner particles moved to the opposite side of the rotation direction with the rotation of the developing roller 510 are directed to the drive gear 516 side is It is formed from the first groove portion 511a provided so as to face the opposite side to 516 to a position closer to the counter driving side end seal 527a. For this reason, the developing roller 510 of the fifth embodiment has two grooves 511a, 511a, so that the toner particles closer to the end seal 527a arranged on the side opposite to the drive gear 516 are moved to the drive gear 516 side. 511b is formed. Therefore, in the vicinity of the counter-driving side end seal 527a, the amount of toner particles moved to the drive gear 516 side by the second groove 511b by the rotation of the developing roller 510 by a predetermined angle is reduced by the first groove 511a. Since the amount of toner particles moved in the direction opposite to that of the drive gear 516 is increased, the toner particle moving efficiency of the second groove 511b is increased.

  For this reason, in the fifth embodiment, the second groove portion 511b provided so that the toner particles moved to the opposite side of the rotation direction with the rotation of the developing roller 510 are directed to the drive gear 516 side is used as the drive gear 516. From the first groove portion 511a provided so as to face the opposite side, a position closer to the counter drive side end seal 527a is provided. When the developing roller 510 provided with such two grooves 511a and 511b is used, in the vicinity of the counter-driving side end seal 527a, the moving direction is greater than the moving direction in which the developing roller 510 is moved by the driving gear 516. It is possible to move more toner particles in the opposite direction. Therefore, even if the developing roller 510 is moved in the opposite direction to the drive gear 516 by power, it is possible to prevent the toner particles from leaking out of the developing devices 51, 52, 53, and 54.

  FIG. 20 is a conceptual diagram for explaining the surface shape of the developing roller according to the first modification of the fifth embodiment.

  As shown in FIG. 20, in the first modification, of the two types of groove portions 511 a and 511 b formed on the developing roller of the second embodiment described above, the second groove portion 511 b having a smaller inclination angle with respect to the shaft is The first groove 511a is provided to a position closer to the counter driving side end seal 527a.

  According to the developing devices 51, 52, 53, and 54 having such a developing roller 510, the direction opposite to the moving direction from the moving direction in which the developing roller 510 is moved by the rotation of the driving gear 516, that is, the driving gear 516. Needless to say, more toner particles are moved in the direction toward. In addition, since the second groove portion 511b having a smaller inclination angle than the first groove portion 511a and having a high toner particle movement efficiency is provided to a position close to the counter drive side end seal 527a, the counter drive side Even in the vicinity of the end seal 527a, more toner particles can be moved in the direction toward the drive gear 516. For this reason, even when the developing roller 510 is moved in the opposite direction to the drive gear 516 by power, the second groove portion 511b is simply made to have an inclination angle smaller than the inclination angle of the first groove portion 511a. According to the embodiment, it is possible to enhance the effect of preventing the toner particles from leaking from the counter driving side end seal 527a side.

  FIG. 21 is a conceptual diagram for explaining the surface shape of the developing roller according to the second modification of the fifth embodiment.

  As shown in FIG. 21, in the second modification, of the two types of groove portions 511a and 511b formed on the developing roller of the third embodiment described above, the second groove portion 511b with the wider width of the groove portion 511 is: The first groove 511a is provided to a position closer to the counter driving side end seal 527a.

  According to the developing devices 51, 52, 53, and 54 having such a developing roller 510, the direction opposite to the moving direction from the moving direction in which the developing roller 510 is moved by the rotation of the driving gear 516, that is, the driving gear 516. Needless to say, more toner particles are moved in the direction toward. In addition, since the second groove portion 511b, which is wider than the first groove portion 511a and has a high toner particle movement efficiency, is provided to a position close to the non-driving side end seal 527a, Even in the vicinity of the part seal 527a, more toner particles can be moved in the direction toward the drive gear 516. Therefore, even when the developing roller 510 is moved in the opposite direction to the drive gear 516 by power, the third embodiment in which the width of the second groove portion 511b is simply made wider than the width of the first groove portion 511a. As a result, it is possible to enhance the effect of preventing the toner from leaking from the counter drive side end seal 527a side.

  FIG. 22 is a conceptual diagram for explaining the surface shape of the developing roller according to the third modification of the fifth embodiment.

  As shown in FIG. 22, in the third modification, of the two types of groove portions 511a and 511b formed on the developing roller 510 of the fourth embodiment described above, the second groove portion 511b having a deeper groove portion 511 is provided. However, it is provided to a position closer to the counter driving side end seal 527a than the first groove portion 511a.

  According to the developing devices 51, 52, 53, and 54 having such a developing roller 510, the direction opposite to the moving direction from the moving direction in which the developing roller 510 is moved by the rotation of the driving gear 516, that is, the driving gear 516. Needless to say, more toner particles are moved in the direction toward. In addition, since the second groove portion 511b, which is deeper than the first groove portion 511a and has a high toner particle movement efficiency, is provided to a position close to the non-driving side end seal 527a, Even in the vicinity of the end seal 527a, more toner particles can be moved in the direction toward the drive gear 516. For this reason, even when the developing roller 510 is moved in the opposite direction to the drive gear 516 by power, the depth of the second groove 511b is simply made deeper than the depth of the first groove 511a. From the configuration, it is possible to enhance the effect of preventing the toner particles from leaking from the side opposite to the driving end seal 527a.

  In the fifth embodiment and the modifications thereof, the example in which the second groove portion 511b is provided to a position closer to the counter-drive side end seal 527a than the first groove portion 511a has been described. However, the anti-drive of the second groove portion 511b is described. The inclination angle of the portion near the side end seal 527a with respect to the axis is made smaller than that of the first groove portion 511a, or the groove width of the second groove portion 511b near the non-driving side end seal 527a is set to the first groove portion 511a. The width of the second groove portion 511b may be made deeper than the first groove portion 511a to increase the efficiency of movement of the toner particles. .

  By the way, the toner is supplied from the toner supply roller 550 to the developing roller 510 of the first to fifth embodiments described above between the end seals 527 abutted at both ends 510b, and the toner is brought to the pressing position of the regulating blade 560. Therefore, the thickness of the toner layer is regulated. At this time, the regulating blade 560 is pressed across both end portions 510b and the central portion 510a of the developing roller 510, but the both end portions 510b of the developing roller 510 and the top surface 512a of the convex portion 512 are at a distance L from the axis C. Therefore, the regulating blade 560 presses the developing roller 510 in a substantially flat state without being largely bent. For this reason, for example, an extremely large gap does not occur between the surface 510d of the developing roller 510 and the regulating blade 560 even in the vicinity of the boundary between the both end portions 510b and the central portion 510a.

  Further, the difference between the convex portion 512 of the surface 510d of the developing roller 510 and the regulating blade 560 and the difference between the groove portion 511 and the regulating blade 560 is not more than twice the volume average particle size. It is possible to make the thickness of the toner layer formed by the toner particles entering between 560 and 560 less than or equal to two toner particles. That is, a large amount of toner particles do not enter the groove portion 511, and most of the toner particles come into contact with either the surface 510 d of the developing roller 510 or the surface of the regulating blade 560 when pressed by the regulating blade 560. Therefore, each toner particle T is easy to roll, and the toner particles do not easily stay in the groove 511, so that the toner particles T can be charged well. For this reason, the toner particles are reliably carried on the developing roller 510 and used for development, and in combination with the fact that no gap is formed between the surface 510 d of the developing roller 510 and the regulating blade 560, the developing device 51. , 52, 53, 54 can prevent the toner particles T from leaking out.

  FIG. 23 is a diagram for explaining a state in which the regulating blade is in contact with the developing roller carrying toner particles.

  In particular, the groove 511 of the developing roller 510 of the present embodiment has a depth of about 7 μm, which is about 1 time as compared with the volume average particle diameter of the toner particles T. For this reason, since the regulating blade 560 is made of rubber and follows the unevenness of the surface 510d of the developing roller 510, the toner having a thickness that forms a layer of toner on the entire surface of the developing roller 510 without overlapping the toner particles T. Layers can be formed. By forming a toner layer having a single particle thickness on the surface 510d of the developing roller 510 in this manner, each toner particle T can be reliably charged in the entire region including the convex portion 512 and the groove portion 511 of the central portion 510a. It is possible to reliably carry the toner on the developing roller 510 to improve transferability during development and to prevent toner from leaking outside the developing device.

=== Other Embodiments ===
The image forming apparatus and the like according to the present invention have been described above based on the above embodiment. However, the above embodiment of the present invention is for facilitating understanding of the present invention and limits the present invention. is not. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes the equivalents thereof.

  In the above embodiment, an example in which the printer includes a plurality of attaching / detaching portions has been described. However, a lid unit that can be closed by inserting a developing device to be attached to only one attaching / detaching portion is provided. You may be the structure provided. In the above-described embodiment, the image forming apparatus including the rotary developing device has been described as an example. However, the present invention is not limited to this. For example, the present invention can be applied to an image forming apparatus provided with a tandem developing device.

  In the above embodiment, the photoconductor as the image carrier has been described as a configuration in which the photosensitive layer is provided on the outer peripheral surface of the cylindrical conductive base material, but the present invention is not limited to this. For example, a so-called photosensitive belt configured by providing a photosensitive layer on the surface of a belt-like conductive substrate may be used.

=== Configuration of Image Forming System etc. ===
Next, an image forming system according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 24 is an explanatory diagram showing an external configuration of the image forming system. The image forming system 700 includes a computer 702, a display device 704, a printer 10, an input device 708, and a reading device 710.

  In this embodiment, the computer 702 is housed in a mini-tower type housing, but is not limited thereto. The display device 704 is generally a CRT (Cathode Ray Tube), a plasma display, a liquid crystal display device, or the like, but is not limited thereto. As the printer 10, the printer described above is used. In this embodiment, the input device 708 uses a keyboard 708A and a mouse 708B, but is not limited thereto. In this embodiment, the reading device 710 uses a flexible disk drive device 710A and a CD-ROM drive device 710B. However, the reading device 710 is not limited to this. Disk) etc. may be used.

  FIG. 25 is a block diagram showing a configuration of the image forming system shown in FIG. An internal memory 802 such as a RAM and an external memory such as a hard disk drive unit 804 are further provided in a housing in which the computer 702 is housed.

  In the above description, an example in which the printer 10 is connected to the computer 702, the display device 704, the input device 708, and the reading device 710 to configure the image forming system has been described. However, the present invention is not limited to this. Absent. For example, the image forming system may include the computer 702 and the printer 10, and the image forming system may not include any of the display device 704, the input device 708, and the reading device 710.

  For example, the printer 10 may have a part of each function or mechanism of the computer 702, the display device 704, the input device 708, and the reading device 710. As an example, the printer 10 includes an image processing unit that performs image processing, a display unit that performs various displays, a recording medium attachment / detachment unit for attaching / detaching a recording medium that records image data captured by a digital camera or the like. It is good also as a structure to have.

  The image forming system realized in this way is a system superior to the conventional system as a whole system.

FIG. 2 is a diagram illustrating main components constituting a printer. It is a figure for demonstrating the structure of the control unit with which the printer was equipped. It is a perspective view of a yellow developing device. It is sectional drawing which showed the main components of the yellow developing device. FIG. 6 is a perspective view showing a developing device with a developing roller removed. It is a conceptual diagram for demonstrating the surface shape of the developing roller which concerns on 1st Embodiment. FIG. 7 is an A arrow view of FIG. 6 showing the arrangement of the developing roller and the regulating blade. It is sectional drawing for demonstrating the cross section when the developing roller which concerns on 1st Embodiment is cut | disconnected by the plane which passes along an axis | shaft. It is a figure for demonstrating a mode that a developing roller is formed by rolling. It is a figure which shows the procedure in which a developing roller is formed. FIG. 11A is a diagram illustrating a state where the drive gear is stopped. FIG. 11B is a diagram illustrating a state in which the developing roller has moved along with the rotation of the drive gear. It is a figure for demonstrating the 1st modification in 1st Embodiment. It is a figure for demonstrating the 2nd modification in 1st Embodiment. It is a conceptual diagram for demonstrating the surface shape of the developing roller which concerns on 2nd Embodiment. It is a figure for demonstrating a mode that a developing roller is formed by rolling. It is a conceptual diagram for demonstrating the surface shape of the developing roller which concerns on 3rd Embodiment. It is a conceptual diagram for demonstrating the surface shape of the developing roller which concerns on 4th Embodiment. It is AA sectional drawing of FIG. It is a conceptual diagram for demonstrating the surface shape of the developing roller which concerns on 5th Embodiment. It is a conceptual diagram for demonstrating the surface shape of the developing roller which concerns on the 1st modification of 5th Embodiment. It is a conceptual diagram for demonstrating the surface shape of the developing roller which concerns on the 2nd modification of 5th Embodiment. It is a conceptual diagram for demonstrating the surface shape of the developing roller which concerns on the 3rd modification of 5th Embodiment. FIG. 6 is a diagram for explaining a state in which a regulating blade is in contact with a developing roller carrying toner particles. 1 is an explanatory diagram showing an external configuration of an image forming system. FIG. 25 is a block diagram illustrating a configuration of the image forming system illustrated in FIG. 24.

Explanation of symbols

10 printer, 20 photoconductor, 30 charging unit, 40 exposure unit,
50 Developer holding unit, 50a, 50b, 50c, 50d Detachable part,
50e central axis, 51 black developer, 52 magenta developer,
53 Cyan developer, 54 Yellow developer, 60 Primary transfer unit,
70 intermediate transfer body, 75 cleaning unit, 76 cleaning blade,
80 secondary transfer unit, 90 fixing unit, 92 paper feed tray,
94 paper feed roller, 95 display unit, 96 registration roller, 100 control unit,
101 main controller, 102 unit controller, 111 CPU,
112 interface, 113 image memory, 116 memory, 120 CPU,
509 Non-rolled processing developing roller, 510 developing roller, 510a central portion,
510b end (both ends), 510c step, 510d surface, 511 groove,
511a One groove part, 511b The other groove part, 511c Bottom face,
511d inclined portion, 512 convex portion, 512a top surface,
513 flange, 513a flange body, 513b shaft,
515 cylindrical member, 516 driving gear, 520 upper seal,
522 seal support sheet metal, 524 seal urging member, 527 end seal,
527a counter drive side end seal, 530 toner accommodating portion,
530a first toner container, 530b second toner container,
540 housing, 540a rib, 540b rib inner surface,
542 Upper housing part, 544 Lower housing part, 545 Partition wall,
550 toner supply roller, 550a roller portion, 550b shaft body,
560 regulating blade, 560a rubber part, 560b rubber support part,
562 blade support sheet metal, 570 blade backing member, 572 opening,
700 image forming system, 702 computer, 704 display device,
708 input device, 708A keyboard, 708B mouse, 710 reader,
710A flexible disk drive device,
710B CD-ROM drive device,
802 internal memory, 804 hard disk drive unit, 900 dice,
900a blade, C axis, T toner (toner particles)

Claims (13)

A developing device having a toner particle carrying roller that is urged in a predetermined direction along an axis when rotated by power transmitted through an inclined gear,
(A) a housing that contains toner particles for developing a latent image carried on the image carrier;
(B) a first groove for moving the toner particles in the predetermined direction at a central portion of the surface facing the opening communicating with the inside and outside of the housing, and the predetermined direction; A second groove portion for moving the toner particles in the opposite direction is formed in a spiral shape at an equal pitch in the axial direction and having an inclination with respect to the axial direction;
A toner particle carrying roller in which the second groove portion has a higher toner particle transfer efficiency than the first groove portion;
(C) end seals for contacting a peripheral surface at both ends of the toner particle carrying roller and sealing a gap with the housing;
A developing device having (d). The developing device according to claim 1 ,
The developing efficiency of the toner particles is enhanced by making the depth of the second groove portion deeper than the depth of the first groove portion. The developing device according to claim 1 or 2 ,
The toner particle transfer efficiency is increased by making the width of the second groove portion wider than the width of the first groove portion. The developing device according to any one of claims 1 to 3,
The developing device according to claim 1, wherein the first groove portion and the second groove portion intersect each other to form a lattice shape. The developing device according to any one of claims 1 to 4,
The developing efficiency of the toner particles is enhanced by making an inclination angle of the second groove portion with respect to the axial direction smaller than an inclination angle of the first groove portion with respect to the axial direction. The developing device according to any one of claims 1 to 5,
The developing device, wherein a distance between the end of the second groove and the end seal is shorter than a distance between the end of the first groove and the end seal. The developing device according to any one of claims 1 to 6 ,
When the toner particle carrying roller is rotated via the inclined gear, the toner particle carrying roller is moved in the predetermined direction, and a part of the groove is opposed to the end seal. Development device. The developing device according to any one of claims 1 to 7 ,
The developing device according to claim 1, wherein the housing has a positioning protrusion that is positioned along the end seal only on the outer side in the axial direction of the end seal. The developing device according to any one of claims 1 to 8 ,
The developing device according to claim 1, wherein the depth of the groove is not more than twice the volume average particle diameter of the toner particles. The developing device according to any one of claims 1 to 9 ,
The developing device according to claim 1, wherein a peripheral surface other than the groove portion in a central portion of the toner particle carrying roller carries the toner particles. The developing device according to any one of claims 1 to 10 ,
A layer thickness regulating member for regulating the layer thickness of the toner particles carried on the toner particle carrying roller;
The developing device according to claim 1, wherein the toner particles carried on the surface are pressed by a plane of the layer thickness regulating member to regulate the layer thickness. (A) A developing device having a toner particle carrying roller that is urged in a predetermined direction along an axis when rotated by power transmitted through an inclined gear,
(A) a housing that contains toner particles for developing a latent image carried on the image carrier;
(B) a first groove for moving the toner particles in the predetermined direction at a central portion of the surface facing the opening communicating with the inside and outside of the housing, and the predetermined direction; A second groove portion for moving the toner particles in the opposite direction is formed in a spiral shape at an equal pitch in the axial direction and having an inclination with respect to the axial direction;
A toner particle carrying roller in which the second groove portion has a higher toner particle transfer efficiency than the first groove portion ;
(C) a developing device having an end seal for contacting a peripheral surface at both ends of the toner particle carrying roller and sealing a gap with the housing;
(B) An image forming apparatus that forms an image using the developing device. A computer and an image forming apparatus connected to the computer,
(A) A developing device having a toner particle carrying roller that is urged in a predetermined direction along an axis when rotated by power transmitted through an inclined gear,
(A) a housing that contains toner particles for developing a latent image carried on the image carrier;
(B) a first groove for moving the toner particles in the predetermined direction at a central portion of the surface facing the opening communicating with the inside and outside of the housing, and the predetermined direction; A second groove portion for moving the toner particles in the opposite direction is formed in a spiral shape at an equal pitch in the axial direction and having an inclination with respect to the axial direction;
A toner particle carrying roller in which the second groove portion has a higher toner particle transfer efficiency than the first groove portion ;
(C) a developing device having an end seal for contacting a peripheral surface at both ends of the toner particle carrying roller and sealing a gap with the housing;
(B) an image forming apparatus that forms an image using the developing device;
An image forming system comprising:

Images