JP2008256794A - Developing device, image forming apparatus and image forming system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that when the developer collected in grooves accumulates, the developer cakes on the contact face, with the result that the quality of an image obtained finally deteriorates. <P>SOLUTION: The developing device includes: a developer storage body having an opening and used for storing developer; a rotatable developer carrier disposed facing the opening and used for holding the developer thereon; and a sealing member disposed such that its face is in contact with the rotating developer carrier roller, used for preventing the developer from leaking from a gap between the developer carrier roller and the developer storage body, and having grooves formed in the contact face so that the lengthwise direction of the sealing member is perpendicular to the rotating axis of the developer carrier roller. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

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

Image forming apparatuses such as laser beam printers are already well known. In such an image forming apparatus, there is provided a developer containing body having an opening for containing the developer, and a rotatable developer carrying provided facing the opening for carrying the developer. A roller, and a seal member for contacting the rotating developer carrying roller at a contact surface to prevent leakage of the developer from between the developer carrying roller and the developer container. Some have a developing device. As the seal member, for example, a seal obtained by forming a polymer material such as polyethylene into a sheet shape is used (see, for example, Patent Document 1).
JP 58-210929 A

  By the way, a groove part may be formed on the contact surface in the process of forming the seal member. In this way, when the developer carrying roller carrying the developer contacts the seal member having the groove on the contact surface, the developer may be collected in the groove. When the developer collected in the groove portion accumulates in the groove portion, a fixed substance of the developer is formed on the contact surface. And as the thickness of the fixed matter increases, the developing device becomes difficult to develop properly, and the quality of the finally obtained image also deteriorates.

  The present invention has been made in view of such problems, and an object of the present invention is for the developing device to appropriately perform development.

In order to solve the above-described problems, the main present invention includes a developer container for containing a developer and an opening, and a rotatable container for carrying the developer provided to face the opening. The developer carrying roller and the rotating developer carrying roller are brought into contact with each other at a contact surface to prevent leakage of the developer from between the developer carrying roller and the developer container. A developing device, comprising: a sealing member having a groove portion whose longitudinal direction intersects a rotation axis direction of the developer carrying roller on the contact surface.
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.
First, a developer container that has an opening and accommodates a developer, a rotatable developer carrying roller that is provided facing the opening and carries the developer, and the developing that rotates. A seal member for contacting the developer carrying roller at a contact surface to prevent leakage of the developer from between the developer carrying roller and the developer containing body, the longitudinal direction of which is the A developing device comprising: a seal member having a groove portion intersecting with a rotation axis direction of the developer carrying roller on the contact surface.

  The developer carrying roller rotates so as to slide on the contact surface of the seal member. At this time, if the longitudinal direction of the groove provided on the contact surface intersects the rotation axis of the developer carrying roller, the developer collected in the groove moves along the longitudinal direction of the groove. To come. As a result, the developer is dispersed in the groove, and the deposition of the developer in the groove is suppressed. As a result, the growth of the fixed substance of the developer in the thickness direction is suppressed, and the developing device can appropriately perform development.

  Further, the groove portion is a plurality of groove portions arranged in the rotation axis direction on the contact surface, and the developer carrying roller has a regularly arranged convex portion and a concave portion. It may be done.

  Further, the convex portion has a flat top surface surrounded by the concave portion, and the maximum width in the direction along the rotation axis direction of the top surface is between two groove portions adjacent to each other. The distance from one groove part to the other groove part may be larger than the arithmetic average value in the plurality of groove parts. In such a case, the effect of suppressing developer deposition is further improved. As a result, the developing device can perform development more appropriately.

  Further, the concave portion is a spiral first concave portion and a second concave portion having different inclination angles with respect to the circumferential direction of the developer carrying roller, and the first concave portion and the second concave portion intersect each other. It may be a lattice shape.

  The top surface is a rhombus top surface surrounded by the first recess and the second recess, and one of the two diagonal lines of the rhombus top surface is in the direction of the rotation axis. It may be along. In such a case, the developer in the groove portion also moves in the longitudinal direction of the groove portion and in the width direction of the groove portion intersecting with the longitudinal direction. For this reason, the developer is more easily dispersed in the groove portion, and the effect of suppressing the deposition of the developer is further improved. As a result, the developing device can perform development more appropriately.

  Further, each of the first recess and the second recess has a flat bottom surface and a pair of inclined surfaces that are adjacent to the bottom surface and face each other. While the agent-carrying roller rotates, a groove portion that is opposed to the pair of inclined surfaces that the first concave portion and the second concave portion respectively have may be included. In such a case, the developer is more easily dispersed in the groove portion, and the effect of suppressing the deposition of the developer is further improved. As a result, the developing device can perform development more appropriately.

  And a developer container for accommodating the developer, a rotatable developer carrying roller provided so as to face the opening, and carrying the developer, and the rotating developer. A seal member for contacting the developer carrying roller at a contact surface to prevent leakage of the developer from between the developer carrying roller and the developer containing body, the longitudinal direction of which is the It is also possible to realize an image forming apparatus including a developing device having a seal member provided with a groove portion intersecting with the rotation axis direction of the developer carrying roller on the contact surface. In such an image forming apparatus, the developing device can appropriately perform development.

  Further, the computer and an image forming apparatus connectable to the computer, the developer container having an opening and accommodating the developer, and provided facing the opening, the developer A rotatable developer carrying roller for carrying, and a contact surface of the rotating developer carrying roller with the contact surface of the developer carrying roller between the developer carrying roller and the developer container; An image provided with a developing device having a seal member for preventing leakage, the seal member having a groove portion whose longitudinal direction intersects the rotation axis direction of the developer carrying roller on the contact surface An image forming system including the forming apparatus can also be realized. In such an image forming system, the developing device can appropriately perform development.

=== Overview of Image Forming Apparatus ===
Next, an outline of a laser beam printer (hereinafter also simply referred to as a printer 10) as an example of the “image forming apparatus” will be described with reference to FIG. FIG. 1 is a diagram illustrating main components constituting the printer 10. In FIG. 1, the vertical direction is indicated by an arrow. For example, the paper feed tray 92 is disposed at the lower part of the printer 10.

<<< Configuration Example of Printer 10 >>>
The printer 10 according to this embodiment is an apparatus that forms an image on a medium using a developer. The developer according to the exemplary embodiment is a toner including mother particles and an external additive externally added to the mother particles. The mother particles are toner mother particles formed from materials such as a colorant, a charge control agent, a release agent (WAX), and a resin. On the other hand, the external additive is a mixture of silica and titanium oxide. However, the material of the external additive is not limited to the above materials, and other external additives include fine particles of metal oxides such as aluminum oxide, strontium titanate, cerium oxide, magnesium oxide, and chromium oxide, and nitride such as silicon nitride. It is also possible to use fine particles of carbides, fine particles of carbides such as silicon carbide, fine particles of metal salts such as calcium sulfate, barium sulfate and calcium carbonate, inorganic fine particles such as a composite thereof, and organic fine particles such as acrylic fine particles. In the present embodiment, the volume average particle size of the external additive is 0.001 to 1 μm.

  As shown in FIG. 1, the printer 10 includes a charging unit 30, an exposure unit 40, a YMCK developing unit 50, a primary transfer unit 60, an intermediate transfer body 70, and a cleaning unit 75 along the rotation direction of the photoreceptor 20. Further, the image forming apparatus includes a secondary transfer unit 80, a fixing unit 90, a display unit 95 which is a liquid crystal panel as a means for notifying a user, and a control unit 100 which controls these units and operates as a printer. ing.

  The photoreceptor 20 has a cylindrical conductive substrate and a photosensitive layer formed on the outer peripheral surface thereof, and is rotatable about a central axis. In the present embodiment, as shown 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 irradiates the charged photoconductor 20 with a modulated laser based on an image signal input from a host computer (not shown).

  The YMCK developing unit 50 stores the latent image formed on the photoconductor 20 in the toner stored in the “developing device”, that is, the black (K) toner stored in the black developing device 51, and the magenta developing device 52. This is a device for developing using the magenta (M) toner, the cyan (C) toner accommodated in the cyan developing device 53, and the yellow (Y) toner accommodated in the yellow developing device 54.

  The YMCK developing unit 50 can move the positions of the four developing devices 51, 52, 53, 54 by rotating with the four developing devices 51, 52, 53, 54 mounted. Yes. That is, the YMCK developing unit 50 holds the four developing devices 51, 52, 53, 54 by four holding portions 55a, 55b, 55c, 55d, and the four developing devices 51, 52, 53, 54 is rotatable around the central axis 50a while maintaining the relative position thereof. Each time image formation for one page is completed, it is selectively opposed to the photoconductor 20, and is formed on the photoconductor 20 with the toner accommodated in each developing device 51, 52, 53, 54. The latent images are developed sequentially. Each of the four developing devices 51, 52, 53, 54 described above is detachable from the holding portion of the YMCK developing unit 50. 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 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 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 medium 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 remaining on the photoreceptor 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 and a control signal are input to the main controller 101, and in response to a command based on the image signal and the control signal. A unit controller 102 controls each of the units and forms an image.

<<< Example of Operation of Printer 10 >>>
Next, the operation of the printer 10 configured as described above will be described. First, when an image signal and a control signal from a host computer (not shown) are input to the main controller 101 of the printer 10 via the interface 112 (labeled I / F in FIG. 2), a command from the main controller 101 is sent. The photoconductor 20, the developing roller 510, which will be described later, and the intermediate transfer member 70 are rotated by the control of the unit controller 102 based on the above. The photoconductor 20 is sequentially charged by the charging unit 30 at the charging position while rotating.

  The charged area of the photoconductor 20 reaches the exposure position as the photoconductor 20 rotates, and the exposure unit 40 forms a latent image in the area according to image information relating to the first color, for example, the yellow color. . In the YMCK developing unit 50, a yellow developing device 54 that contains yellow (Y) toner is located 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 (Y) 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 yellow (Y) toner is applied to the primary transfer unit 60. During this time, the photosensitive member 20 and the intermediate transfer member 70 are in contact with each other, and the secondary transfer unit 80 is separated from the intermediate transfer member 70.

  The above processing is sequentially executed for each developing device for the second color, the third color, and the fourth color, so that four color toner images corresponding to the respective image signals are transferred to the intermediate transfer member 70. It is transcribed and superimposed. 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 the medium by the secondary transfer unit 80. The medium 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 medium is heated and pressed by the fixing unit 90 and fused to the medium. On the other hand, after the primary transfer position has passed, the toner adhering to the surface of the photoreceptor 20 is scraped off by the cleaning blade 76 supported by the cleaning unit 75, and is charged for forming the next latent image. Prepare. The toner scraped off is collected by a residual toner collecting unit (not shown) provided in the cleaning unit 75.

<<< Overview of control unit >>>
Next, the configuration of the control unit 100 will be described with reference to FIG. FIG. 2 is a block diagram showing a control unit of the printer 10 of FIG.
The main controller 101 of the control unit 100 is connected to a host computer via an interface 112 and includes an image memory 113 for storing image signals input from the host computer. The unit controller 102 is electrically connected to each unit (charging unit 30, exposure unit 40, YMCK developing unit 50, primary transfer unit 60, cleaning unit 75, secondary transfer unit 80, fixing unit 90, display unit 95) of the apparatus main body. Each unit is controlled based on a signal input from the main controller 101 while detecting a state of each unit by receiving a signal from a sensor included in them.

=== Overview of Developing Device ===
Next, a configuration example and an operation example of the developing device will be described with reference to FIGS. FIG. 3 is a conceptual diagram of the developing device. FIG. 4 is a cross-sectional view showing main components of the developing device. FIG. 5 is a perspective view showing the holder 526 in which the developing roller 510, the upper seal 520, and the regulating blade 560 are assembled. FIG. 6 is a perspective view showing a state in which the holder 526 is attached to the housing 540.

  Note that the cross-sectional view shown in FIG. 4 represents a cross-section obtained by cutting the 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 photoreceptor 20.

  The YMCK developing 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 a yellow ( Y) Although a yellow developing device 54 containing toner is provided, the configuration of each developing device is the same, so the yellow developing device 54 will be described below.

<<< Configuration of Yellow Developing Device 54 >>>
The yellow developing device 54 includes a developing roller 510 as an example of a “developer carrying roller”, an upper seal 520 as an example of a “seal member”, an upper seal urging member 524, a toner container 530, and a “developer container”. As an example, a housing 540, a toner supply roller 550, a regulating blade 560, and the like are included.

  The developing roller 510 is a member made of an aluminum alloy, an iron alloy, or the like, and rotates in a state where yellow (Y) toner is carried, whereby the yellow (Y) toner is opposed to the photoconductor 20 (development position). Transport to. A shaft portion 510b (see FIG. 10) is provided at an end portion of the developing roller 510 in the rotation axis direction (hereinafter simply referred to as the axial direction), and the shaft portion 510b is described later as shown in FIG. Is supported by a developing roller support plate 526b of a holder 526 via a bearing 576. Thereby, the developing roller 510 is rotatably supported. The developing roller 510 is supported in a state where the axial direction of the developing roller 510 and the longitudinal direction of the yellow developing device 54 are along each other. The surface shape of the developing roller 510 of this embodiment will be described later.

  The housing 540 is manufactured by welding a plurality of integrally molded resin housing parts, that is, an upper housing part 542 and a lower housing part 544, and accommodates yellow (Y) toner therein. is doing. The interior of the housing 540 is divided into two toner accommodating portions 530a and 530b by a partition wall 545 that protrudes inwardly (in the vertical direction in FIG. 4) from the inner wall. Further, as shown in FIG. 4, the housing 540 has an opening 572 in the lower toner accommodating portion 530 a, and the developing roller 510 described above is provided facing the opening 572. That is, the opening 572 is formed along the axial direction of the developing roller 510.

  The toner supply roller 550 is made of polyurethane foam or the like, and is a roller that contacts the developing roller 510 while being elastically deformed in the housing 540. The toner supply roller 550 supplies yellow (Y) toner accommodated in the housing 540 to the developing roller 510 and peels unused toner remaining on the developing roller 510 after development from the developing roller 510.

  The upper seal 520 is in contact with the surface (outer peripheral surface) of the developing roller 510 and prevents yellow (Y) toner contained in the housing 540 from leaking between the developing roller 510 and the housing 540. A seal made of polyethylene or the like. The upper seal 520 is provided along the above-described opening 572. More specifically, as shown in FIG. 4, the cross-sectional shape of the upper seal 520 along the longitudinal direction of the upper seal 520 is as shown in FIG. It is fixed on an upper seal support plate 526a of a holder 526, which will be described later, in a bent state so as to be L-shaped. The surface of the upper seal 520 facing the developing roller 510 (hereinafter referred to as a facing surface 520d) is in contact with the developing roller 510 with a width. That is, the facing surface 520d has a contact surface 520b that contacts the developing roller 510. Further, as shown in FIGS. 5 and 6, the upper seal 520 is fixed with the longitudinal direction of the facing surface 520 d (that is, the longitudinal direction of the contact surface 520 b) along the axial direction of the developing roller 510. . The upper seal 520 allows the yellow (Y) toner remaining on the developing roller 510 after passing through the developing position to move into the housing 540.

  In the present embodiment, as shown in FIG. 4, the surface of the upper seal 520 opposite to the contact surface 520b (this surface is also referred to as the opposite surface 520c), the upper seal support plate 526a, The upper seal urging member 524 made of an elastic body such as malt plain is provided in a compressed state. That is, the contact surface 520b is in contact with the developing roller 510 while being pressed against the developing roller 510 by the biasing force of the upper seal biasing member 524. Note that the position where the upper seal 520 and the developing roller 510 abut (that is, the position of the abutting surface 520 b) is above the rotation axis of the developing roller 510. Details of the upper seal 520 of this embodiment will be described later.

  The regulating blade 560 contacts the developing roller 510 along the axial direction thereof, regulates the layer thickness of the yellow (Y) toner carried on the developing roller 510, and imparts electric charge to the yellow (Y) toner. . The regulation blade 560 includes a rubber part 562 and a rubber support part 564. The rubber portion 562 is made of silicon rubber, urethane rubber, or the like. As shown in FIG. 4, a portion (abutting portion 560a) that is a predetermined distance away from the tip of the rubber portion 562 has a width against the developing roller 510. It touches. The rubber support portion 564 includes a thin plate 564a having a spring property, and supports the rubber portion 562 at one end portion 564d in the short direction of the thin plate 564a. The rubber portion 562 is pressed against the developing roller 510 by the urging force of the thin plate 564a. The other end portion 564e in the short side direction of the rubber support portion 564 is fixed to the support metal plate 564b. As shown in FIG. 5, both longitudinal end portions 564c of the support metal plate 564b are the regulating blade support plate 526c of the holder 526 described later. It is fixed to.

  Further, an end seal 574 is provided on the outer side in the longitudinal direction of the rubber portion 562 of the regulating blade 560, as shown in FIG. The end seal 574 abuts along the circumferential direction of the developing roller 510 at the axial end of the developing roller 510 to prevent toner leakage between the peripheral surface and the housing 540.

  The holder 526 is a metal assembly member for assembling the developing roller 510, the regulation blade 560, the upper seal 520, the end seal 574, and the upper seal biasing member 524. As shown in FIG. 5, the holder 526 includes an upper seal support plate 526a along the longitudinal direction, a regulation blade support plate 526c along the longitudinal direction, and the upper seal support plate 526a and regulation in the longitudinal direction. A developing roller support plate 526b provided outside the blade support plate 526c and intersecting the longitudinal direction. As shown in FIGS. 5 and 6, the developing roller 510 is supported by the developing roller support plate 526 b in a state where the axial direction thereof is along the longitudinal direction of the holder 526. The upper seal 520 is supported by an upper seal support plate 526a with the longitudinal direction thereof being along the axial direction of the developing roller 510. Further, the upper seal urging member 524 is supported by the upper seal support plate 526a with the longitudinal direction thereof being along the axial direction of the developing roller 510. The holder 526 in which the developing roller 510, the upper seal 520, and the like are assembled is attached to the housing 540 via the housing seal 546 (see FIG. 4).

<<< Operation of Yellow Developing Device 54 >>>
In the yellow developing device 54 configured as described above, the toner supply roller 550 supplies the yellow (Y) toner stored in the toner container 530 to the developing roller 510. The yellow (Y) toner supplied to the developing roller 510 reaches the contact position of the regulating blade 560 as the developing roller 510 rotates, and the layer thickness is regulated when passing through the contact position. Charge is applied. The yellow (Y) toner on the developing roller 510 to which the layer thickness is regulated and the electric charge is applied reaches the developing position facing the photoconductor 20 by further rotation of the developing roller 510, and the developing position is under an alternating electric field at the developing position. Then, it is used for developing the latent image formed on the photoconductor 20. The yellow (Y) toner 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 yellow (Y) toner still remaining on the developing roller 510 is peeled off by the toner supply roller 550.

=== About the Top Seal and the Developing Roller of this Embodiment ===
Here, details regarding the upper seal 520 and the developing roller 510 of this embodiment will be described. Specifically, the surface shape and the manufacturing method of the upper seal 520 and the developing roller 510 will be described.

<<< Surface shape of upper seal >>>
First, the surface shape of the upper seal 520 will be described with reference to FIGS. FIG. 7 is a diagram illustrating a state in which the upper seal 520 is in contact with the developing roller 510, and is an enlarged view of a portion surrounded by a broken line in FIG. FIG. 8 is a view showing the surface shape of the upper seal 520 on the contact surface 520b side, and is a cross-sectional view taken along line AA in FIG. In FIG. 7, the axial direction of the developing roller 510 is indicated by an arrow. In FIG. 8, the axial direction and the thickness direction of the upper seal 520 are indicated by arrows, respectively. 7 and 8, the scale of each part such as the groove part 521 is different from the actual one in order to make the drawings easy to understand.

  In the present embodiment, among the surfaces of the upper seal 520, the outer surface 520a facing the outside of the developing device has a streak shape whose longitudinal direction intersects the longitudinal direction of the upper seal 520 as shown in FIG. A groove 521 is provided. Further, the outer surface 520a includes a facing surface 520d including a contact surface 520b, and the corresponding contact surface 520b is also provided with the groove portion 521. The longitudinal direction of the groove 521 also intersects with the axial direction of the developing roller 510, and in particular, the contact surface 520b is along the rotational direction of the developing roller 510. A plurality of grooves 521 are arranged in the longitudinal direction of the upper seal 520, that is, in the axial direction, and are provided in the entire region from one end to the other end of the outer surface 520a of the upper seal 520 in the longitudinal direction. In addition, a non-groove portion 522 adjacent to the groove portion 521 is provided between the groove portions 521.

  Hereinafter, the shapes of the groove 521 and the non-groove 522 will be described with reference to FIG. The groove portion 521 is a portion located at a position lower than a reference position (a position indicated by a symbol BL in FIG. 8) in the thickness direction of the upper seal 520. On the other hand, the non-groove portion 522 is a portion at a position higher than the reference position. Therefore, the boundary between the groove part 521 and the non-groove part 522 is located at the reference position. In the present embodiment, the reference position is an average line obtained from the roughness curve of the outer surface 520a in the thickness direction of the upper seal 520 (the roughness curve and the average line conform to JIS B 0601-1994). Position. However, the reference position is not limited to this, and may be set to another position. For example, a position at a predetermined distance from the opposite surface 520c in the thickness direction of the upper seal 520 may be set as the reference position.

  Further, the maximum height difference (indicated by symbol Y in FIG. 8) of the contact surface 520b is about 1 μm. Here, the maximum height difference is an arithmetic average value of the maximum height Ry (conforming to JIS B 0601-1994) measured in each of a plurality of measurement ranges set in the contact surface 520b.

  Further, in the present embodiment, the distance from the boundary on the one end side in the axial direction in one groove portion 521 to the boundary on the one end side in the axial direction in the other groove portion 521 (that is, in FIG. The arithmetic average value of the distances indicated by Sn-1 and Sn (hereinafter referred to as the distance between the groove portions) (hereinafter referred to as the average value of the distance between the groove portions) is about 4 μm. Here, the average value of the distance between the groove portions is “the arithmetic average value in the plurality of groove portions 521 of the distance from one groove portion 521 to the other groove portion 521 of the two adjacent groove portions 521”. is there. Moreover, in this embodiment, the average value of the distance between groove parts means the arithmetic average value of the uneven | corrugated average space | interval Sm (based on JISB0601-1994) measured in the said some measurement range. When measuring the average interval Sm between the concaves and convexes, the groove 521 is concave, and one of the two non-grooves 522 adjacent to the groove 521 is convex. Further, in the present embodiment, “the arithmetic average value in the plurality of groove portions 521 of the distance from one groove portion 521 to the other groove portion 521 of the two adjacent groove portions 521” is the distance between the groove portions. The average value is not limited to this. For example, the arithmetic average value in the plurality of groove portions 521 of the distance from the groove bottom of one groove portion 521 to the groove bottom of the other groove portion 521 may be used.

<<< Method for Manufacturing Upper Seal >>>
Next, a method for manufacturing the upper seal 520 having the above surface shape will be described with reference to FIGS. 9A to 9E. FIG. 9A to FIG. 9E are diagrams for explaining the manufacturing process of the upper seal 520 and are schematic diagrams showing a transition until the upper seal 520 is finally obtained from the material of the upper seal 520. In FIG. 9B, the width direction of the sheet 901 is indicated by an arrow. In FIG. 9C, the width direction of the sheet 901 and the intersecting direction intersecting the width direction are indicated by arrows. In FIG. 9D, the longitudinal direction of the upper seal 520 is indicated by an arrow.

  In the present embodiment, a columnar base material 900 made of a resin such as polyethylene as shown in FIG. 9A is used as the material of the upper seal 520. Of course, the material of the base material 900 is the material of the upper seal 520. Next, as shown in FIG. 9B, the cutting edge of a blade 902 having a length substantially the same as the length of the base material 900 in the central axis direction is brought into contact with the peripheral surface of the base material 900. At this time, the longitudinal direction of the cutting tool 902 is along the central axis direction of the base material 900, and the cutting edge abuts from one end to the other end of the base material 900 in the central axis direction. When the base material 900 is rotated around the central axis in a state where the cutting edge is in contact with the peripheral surface of the base material 900, a sheet 901 as shown in FIG. 9B is continuously formed from the outer periphery of the base material 900. And cut out. At this time, the contact angle when the blade 902 is brought into contact with the peripheral surface of the base material 900 is adjusted so that the thickness of the sheet 901 becomes the thickness of the upper seal 520 that is finally completed.

  Here, since the blade edge has minute irregularities, as shown in FIG. 9B, when the sheet 901 is cut out, the surface of the sheet 901 (the surface on the side where the blade edge abuts) is placed on the sheet 901. A plurality of streak-like groove portions intersecting with the width direction are formed in a state of being aligned in the width direction of the sheet 901 (in FIG. 9B, for convenience of illustration, the groove portions are formed only for a part of the surface. Show). That is, in this embodiment, the groove 521 provided on the outer surface 520a of the upper seal 520 is formed on the surface corresponding to the outer surface 520a of the sheet 901 as a scratch generated when the sheet 901 is cut out. Next, the sheet 901 is cut out from the base material 900 by a predetermined length and then separated from the base material 900. Then, the upper seal 520 as shown in FIG. 9D is obtained by extracting the upper seal 520 from a predetermined portion of the sheet 901 (the portion marked with symbol A in FIG. 9C). At this time, as shown in FIG. 9C, the upper seal 520 is extracted so that the longitudinal direction of the upper seal 520 is along the width direction of the sheet 901. Further, as described above, a groove portion whose longitudinal direction intersects the width direction of the sheet 901 is formed on the surface of the sheet 901 (also in FIG. 9C, only a part of the surface is illustrated for convenience of illustration. , Indicating that the groove is formed). As a result, the surface of the upper seal 520 that is finally obtained (the surface that becomes the outer surface 520a) is provided with a groove that intersects the longitudinal direction of the upper seal 520, as shown in FIG. 9D.

<<< Surface shape of developing roller >>>
The surface shape of the developing roller 510 will be described with reference to FIGS. 10, 11, 12A, 12B, and 13. FIG. FIG. 10 is a schematic perspective view of the developing roller 510. FIG. 11 is a schematic front view of the developing roller 510. 10 and 11, the axial direction of the developing roller 510 is indicated by an arrow. FIG. 12A is a schematic diagram showing a cross-sectional shape of the first recess 512a. FIG. 12B is a schematic diagram showing a cross-sectional shape of the second recess 512b. In FIG. 12A, the X direction in FIG. 11 is indicated by an arrow, and in FIG. 12B, the Y direction in FIG. 11 is indicated by an arrow. Here, the X direction is the longitudinal direction of the second recess 512b, and the Y direction is the longitudinal direction of the first recess 512a. FIG. 13 is an enlarged view of FIG. 11 and shows the first concave portion 512a, the second concave portion 512b, and the convex portion 515. In FIG. 13, the axial direction and the circumferential direction of the developing roller 510 and the above-described X direction and Y direction are indicated by arrows. Further, in FIG. 13, one groove portion 521 viewed from the developing roller 510 side is indicated by a broken line. 10 to 13, the scales of the first concave portion 512a, the second concave portion 512b, the convex portion 515, and the like are different from actual scales for easy understanding of the drawings.

  The central portion 510a of the surface (outer peripheral surface) of the developing roller 510 is subjected to uneven processing (specifically, through-feed rolling processing described later) in order to appropriately carry the toner. As shown in FIGS. 10 and 11, by the uneven processing, the central portion 510a is regularly provided with a convex portion 515 and a first concave portion 512a and a second concave portion 512b as “concave portions”. It is provided in a state.

  The first concave portion 512a and the second concave portion 512b are two types of spiral grooves having different winding directions. As shown in FIGS. 12A and 12B, the first concave portion 512a and the second concave portion 512b have a cross section. Are substantially identical. Each recess 512 includes a flat bottom surface 514 and a pair of inclined surfaces 513a and 513b that are adjacent to the bottom surface 514 and face each other. The inclination angle of the inclined surfaces 513a and 513b with respect to the bottom surface 514 is about 45 degrees. The groove angle (the angle represented by the symbol α in FIGS. 12A and 12B) is about 90 degrees.

  As shown in FIG. 11, the inclination angles of the first recess 512a and the second recess 512b with respect to the circumferential direction of the developing roller 510 are different from each other, and the longitudinal direction of the first recess 512a is different from that of the developing roller 510. The magnitude of the acute angle formed with the axial direction and the magnitude of the acute angle formed with the longitudinal direction of the second recess 512b and the axial direction are about 45 degrees and about 135 degrees, respectively. And the 1st recessed part 512a and the 2nd recessed part 512b cross | intersect mutually and have comprised the lattice shape, as shown in FIG.10 and FIG.11.

  The convex portion 515 is provided so as to be surrounded by the first concave portion 512a and the second concave portion 512b. As shown in FIGS. 12A and 12B, the convex portion 515 includes a flat top surface 515a and inclined surfaces 513a and 513b adjacent to the top surface 515a (that is, in the present embodiment, the convex portion 515 has a convex shape). The part 515 and the recess 512 share the inclined surfaces 513a and 513b). The top surface 515a is a top surface surrounded by the first recess 512a and the second recess 512b, and as shown in FIG. 11, a large number of meshes are formed in the central portion 510a. The acute angle formed by the longitudinal direction of the first recess 512a and the axial direction is about 45 degrees, and the acute angle formed by the longitudinal direction of the second recess 512b and the axial direction is about 135 degrees. Therefore, the top surface 515a according to the present embodiment is a square. Further, one (the other) of the two diagonal lines of the top surface 515 a is along the axial direction (circumferential direction) of the developing roller 510.

  Below, the dimension of the convex part 515, the 1st recessed part 512a, and the 2nd recessed part 512b is demonstrated, referring FIG. 12A and FIG. 12B, and FIG.

  In the present embodiment, the depth of each recess 512 (indicated by symbols d1 and d2 in FIGS. 12A and 12B) is in the range of about 5 to 10 μm. The width in the X direction of the top surface 515a of the convex portion 515 (corresponding to the length of one side of the top surface 515a that is a square, indicated by the symbol V1 in FIG. 12A) is about 30 μm, and the X of the first concave portion 512a The width in the direction (indicated by symbol W1 in FIG. 12A) is about 50 μm. In other words, the total value of the width of the convex portion 515 and the width of the concave portion 512 in the X direction (hereinafter also referred to as the concave / convex pitch) is about 80 μm. Similarly, the width of the top surface 515a in the Y direction (indicated by symbol V2 in FIG. 12B) is about 30 μm, and the width of the second recess 512b in the Y direction (indicated by symbol W2 in FIG. 12B) is about 50 μm. It is. Therefore, the uneven pitch in the Y direction is also about 80 μm.

  The lengths of the two diagonal lines of the top surface 515a are about 42 μm. Here, of the two diagonal lines of the top surface 515a, the length of the diagonal line along the axial direction of the developing roller 510 is “the maximum width in the direction along the axial direction of the top surface 515a (in FIG. Lmax) ”. That is, the maximum width in this embodiment is about 42 μm. For this reason, the size of the maximum width is larger than the average value of the distances between the groove portions in the plurality of groove portions 521 provided on the contact surface 520b of the upper seal 520 (about 4 μm in this embodiment). Become.

  The developing roller 510 having the first concave portion 512a, the second concave portion 512b, and the convex portion 515 on the surface (more precisely, the central portion 510a) is formed on the upper surface of the upper seal 520 by the contact surface 520b. Abuts on the seal 520. When the developing roller 510 rotates, the groove 521 and the non-groove 522 provided on the contact surface 520b face the first recess 512a, the second recess 512b, and the projection 515. Further, in the present embodiment, as shown in FIG. 11, the concave portions 512 and the convex portions 515 are alternately arranged in the circumferential direction of the developing roller 510 in each axial portion of the central portion 510 a. In the central portion 510 a, there is no region where the concave portion 512 or the convex portion 515 continues in the circumferential direction of the developing roller 510 by the circumferential length of the developing roller 510. For this reason, all of the plurality of grooves 521 included in the upper seal 520 face the concave portion 512 and the convex portion 515 as the developing roller 510 rotates.

  Further, in the present embodiment, a pair of inclined surfaces 513a included in the first recess 512a and a pair of inclined surfaces 513b included in the second recess 512b while the developing roller 510 rotates in the plurality of grooves 521, Opposing groove portions 521 are included. More specifically, as shown in FIG. 13, in the central portion 510a, in the circumferential direction, two inclined surfaces 513a provided in the first recess 512a and facing each other (that is, extending along the Y direction). Two inclined surfaces 513a) and two inclined surfaces 513b provided in the second recess 512b and facing each other (that is, two types of inclined surfaces 513b extending along the X direction) (for example, In FIG. 13, there is a region indicated by symbol A). Among the plurality of groove portions 521, the groove portion 521 (shown by a broken line in FIG. 13) that faces a region of the central portion 510 a where four kinds of inclined surfaces 513 a and 513 b hang in the circumferential direction. There is a groove 521). Such a groove 521 faces both the pair of inclined surfaces 513a included in the first recess 512a and the pair of inclined surfaces 513b included in the second recess 512b as the developing roller 510 rotates.

<<< Development Roller Manufacturing Method >>>
Next, a method for manufacturing the developing roller 510 having the above-described surface shape will be described with reference to FIGS. 14A to 14E and FIG. 14A to 14E are schematic views showing the transition of the developing roller 510 in the manufacturing process of the developing roller 510. FIG. 15 is an explanatory diagram for explaining the rolling process of the developing roller 510. 14A to 14C show a cross section of the pipe material 600, and FIGS. 14D and 14E show the outer periphery of the pipe material 600, respectively.

First, as shown in FIG. 14A, a pipe material 600 as a base material of the developing roller 510 is prepared. The wall thickness of the pipe material 600 is 0.5 to 3 mm.
Next, as shown in FIG. 14B, flange press-fit portions 602 are formed at both ends in the longitudinal direction of the pipe material 600. The flange press-fit portion 602 is made by cutting.
Next, as shown in FIG. 14C, the flange 604 is press-fitted into the flange press-fit portion 602. In order to ensure the fixing of the flange 604 to the pipe material 600, the flange 604 may be bonded or welded to the pipe material 600 after the flange 604 is press-fitted.
Next, as shown in FIG. 14D, centerless polishing is performed on the surface of the pipe member 600 into which the flange 604 is press-fitted. The centerless polishing is performed over the entire surface.
Next, as shown in FIG. 14E, the pipe material 600 into which the flange 604 is press-fitted is subjected to a rolling process. In this embodiment, so-called through-feed rolling (also called step rolling or through rolling) using two round dies 650 and 652 is performed.

  That is, as shown in FIG. 15, two round dies 650 and 652 arranged so as to sandwich the pipe material 600 as a work are placed on the pipe material 600 with a predetermined pressure (the direction of the pressure in FIG. The two round dies 650 and 652 are rotated in the same direction (refer to FIG. 15) in a state where they are pressed with a symbol P). In the through-feed rolling, as the round dies 650 and 652 rotate, the pipe material 600 rotates in the direction opposite to the rotation direction of the round dies 650 and 652 (see FIG. 15). Move in the direction indicated by. Convex portions 650a and 652a for forming spiral grooves 680 (corresponding to the first concave portion 512a and the second concave portion 512b in the developing roller 510) are provided on the surfaces of the round dies 650 and 652. When the convex portions 650 a and 652 a deform the pipe material 600, a spiral groove 680 is formed in the pipe material 600.

  Then, after the rolling process is finished, the surface of the central portion 510a is plated. In the present embodiment, electroless Ni—P plating is used as the plating, but is not limited to this, and for example, hard chrome plating or electroplating may be used.

=== Effectiveness of Developing Device of this Embodiment ===
The developing device of the present embodiment has an opening 572, a housing 540 for accommodating toner, and a rotatable developing roller 510 that is provided facing the opening 572 and carries toner, and rotates. An upper seal 520 that contacts the developing roller 510 at the contact surface 520b to prevent leakage of toner from between the developing roller 510 and the housing 540, the longitudinal direction of which is the developing roller And an upper seal 520 having a groove portion 521 intersecting with the axial direction 510 on the contact surface 520b. With such a developing device, it is possible to perform development appropriately.

  Hereinafter, the effectiveness of the developing device of the present embodiment will be described with reference to FIGS. 16A and 16B and FIG. FIG. 16A and FIG. 16B are views of a fixed object (indicated by symbol X in FIG. 16A and FIG. 16B) deposited on the contact surface 520b of the upper seal 520 observed with a laser microscope. FIG. 16A shows a fixed object formed when the groove portion 521 extends along the axial direction, and FIG. 16B shows a fixed object formed when the groove portion 521 intersects the axial direction. ing. FIG. 17 is a schematic diagram for explaining that the accumulation of the fixed matter is suppressed in the present embodiment. In FIGS. 16A and 16B, the longitudinal direction of the upper seal 520 is indicated by an arrow. FIG. 17 shows the axial direction of the developing roller 510.

  The upper seal 520 (particularly, the upper seal 520 made of a resin such as polyethylene) may be manufactured by the method described in the section “Method for Manufacturing Upper Seal”. That is, the upper seal 520 is obtained by cutting out the sheet 901 from the base material 900 and extracting the upper seal 520 from a predetermined portion of the sheet 901.

  Here, from the sheet 901 (the portion indicated by the symbol B in FIG. 9C described above) so that the longitudinal direction of the upper seal 520 is along the direction (crossing direction) intersecting the width direction of the sheet 901. When the upper seal 520 is extracted, a groove 521 whose longitudinal direction is along the longitudinal direction of the upper seal 520 is provided on the surface of the upper seal 520 (the surface on the side that becomes the outer surface 520a). When the upper seal 520 is attached to the developing device, the longitudinal direction of the groove 521 is in a state along the axial direction of the developing roller 510. On the other hand, if the developing roller 510 is in contact with the upper seal 520 at the contact surface 520b in a state where the toner is carried, the toner may be collected in the groove portion 521. More precisely, of the toner, an external additive having a particle size smaller than the depth and width of the groove 521 is collected in the groove 521. At this time, if the longitudinal direction of the groove portion 521 is along the longitudinal direction of the upper seal 520, the external additive collected in the groove portion 521 becomes difficult to move and stagnates in the groove portion 521. End up. Eventually, the external additive adheres to the contact surface 520b, and gradually accumulates in the groove as the number of image forming operations of the printer 10 increases.

  Then, as the deposition of the external additive proceeds, a floating island-like fixed object as shown in FIG. 16A is formed on the contact surface 520b. Further, the fixed matter comes into contact with the toner carried on the developing roller 510, and the release agent (WAX) contained in the toner adheres to the fixed matter. When the fixed matter to which the release agent adheres in this way comes into contact with the surface of the developing roller 510 carrying the toner, the chargeability of the toner carried on the portion in contact with the fixed matter decreases. As a result, charging unevenness occurs in the toner carried on the developing roller 510, it becomes difficult for the developing device to properly develop, and the quality of the finally obtained image is also deteriorated (for example, streaks in the image). Color unevenness occurs). Further, as the thickness of the fixed object (indicated by symbol h1 in FIG. 16A) increases, the fixed object is more likely to come into contact with the developing roller 510, and toner charging unevenness in the developing roller 510 becomes conspicuous. Further, when the longitudinal direction of the groove portion 521 is along the longitudinal direction of the upper seal 520 (that is, the axial direction of the developing roller 510), the external additive is easily deposited in the groove portion 521. As a result, the thickness of the fixed object becomes thick (for example, the thickness h1 at the stage where the number of image formation reaches 2000) is about 6 μm, and the development of the developing device cannot be appropriately performed.

  On the other hand, in the present embodiment, the longitudinal direction of the groove 521 provided in the contact surface 520b (the direction passing through the paper surface in FIG. 17) intersects the longitudinal direction of the upper seal 520. The longitudinal direction of the groove 521 also intersects the axial direction of the developing roller 510. In particular, on the contact surface 520 b, the longitudinal direction of the groove 521 is along the rotation direction of the developing roller 510. With such a configuration, even if the external additive in the toner is collected in the groove 521, the external additive can easily move along the longitudinal direction of the groove 521. More specifically, the developing roller 510 rotates so that its surface (more precisely, the convex portion 515) rubs on the contact surface 520b. At this time, as shown in FIG. 17, the external additive (indicated by symbol G in FIG. 17) collected in the groove 521 comes into contact with the surface of the developing roller 510. Here, as described above, since the rotation direction of the developing roller 510 and the longitudinal direction of the groove portion 521 are along the contact surface 520b, the external additive in contact with the surface of the developing roller 510 is the groove portion 521. It becomes easy to move along the longitudinal direction. As a result, the external additive is dispersed in the groove portion 521, and accumulation of the external additive in the groove portion 521 is suppressed. Then, as a result of suppressing the accumulation of the external additive, as shown in FIG. 16B, although the fixed material of the external additive is formed on the contact surface 520b also in this embodiment, the growth of the fixed material is suppressed, The thickness of the fixed matter (indicated by symbol h2 in FIG. 16B) is also smaller than the conventional one (the thickness h2 when the number of image formation reaches 2000) is about 3 μm). As described above, when the longitudinal direction of the groove 521 intersects the axial direction of the developing roller 510, the growth of the fixed matter is suppressed and the developing device develops more appropriately as compared with the case where the longitudinal direction of the developing roller 510 is along the axial direction. It becomes possible to do. As a result of suppressing the growth of the fixed matter, the period during which the developing device can appropriately perform development (in other words, the life of the developing device) is also improved.

=== Other Embodiments ===
As described above, the developing device, the image forming apparatus, and the like according to the present invention have been described based on the above embodiment. However, the above embodiment of the present invention is for facilitating understanding of the present invention, and It is not limited. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes the equivalents thereof. Further, the embodiments of the present invention are not limited to the numerical values, materials, and manufacturing methods described in the above description. In particular, the dimensions of the convex portion 515, the first concave portion 512a, and the second concave portion 512b are not limited to the values described in the above embodiment, for example, the values shown in FIG. Also good. FIG. 18 is a diagram illustrating an example of variations in the dimension values of the convex portion 515, the first concave portion 512a, and the second concave portion 512b. In FIG. 18, the width V1 in the X direction of the top surface 515a of the convex portion 515 (the width V2 of the top surface 515a in the Y direction) and the width W1 in the X direction of the first concave portion 512a (of the second concave portion 512b). A combination of the width W2) in the Y direction, the concave-convex pitch, and the depths d1, d2 of the concave portions 512 is shown for each shape. The shape number shown in FIG. 18 is a number for specifying the combination. Moreover, in the said embodiment, although the inclination angle with respect to the bottom face 514 of inclined surface 513a, 513b was about 45 degree | times (refer FIG. 12A and FIG. 12B), it is not limited to this, For example, , About 90 degrees.

  In the above embodiment, the groove 521 provided on the contact surface 520b of the upper seal 520 is a scratch generated on the surface of the sheet 901 when the sheet 901 is cut out from the base material 900 that is the material of the upper seal 520. It was supposed to be. For this reason, the distance between the groove portions varies, but the present invention is not limited to this, and the groove portion 521 may be formed so that the distance between the groove portions is uniform. In order to form the groove 521 on the contact surface of the upper seal 520 so that the distance between the grooves is uniform, for example, when the upper seal 520 is obtained by mold forming, a protrusion or the like is formed in the mold. A site for forming the groove 521 may be provided.

  In the above-described embodiment, the intermediate transfer type full-color laser beam printer has been described as an example of the image forming apparatus. However, the present invention is not limited to the intermediate transfer type, but a full-color laser beam printer, a monochrome laser beam printer, a copying machine, and a facsimile machine. The present invention can be applied to various image forming apparatuses. In the above embodiment, the image forming apparatus provided with the rotary type developing device has been described as an example. However, the present invention is not limited to this, and the image forming apparatus provided with the tandem type developing device also includes the present embodiment. The invention can be applied.

  In the above-described embodiment, the surface of the developing roller 510 is provided with the regularly arranged convex portions 515 and the concave portions 512, but the present invention is not limited to this. For example, the convex portion 515 and the concave portion 512 may not be regularly arranged.

  In the above embodiment, the convex portion 515 has a flat top surface 515 a surrounded by the concave portion 512 on all sides. However, the present invention is not limited to this. For example, the central portion 510a of the surface of the developing roller 510 may be blasted to form a convex portion 515 having a sharp tip. However, when the convex portion 515 has a flat top surface 515a, the developing roller 510 comes into contact with the upper seal 520 so that the flat top surface 515a slides on the contact surface 520b (that is, the developing roller 510 is It will contact the upper seal 520 in a plane). As a result, the external additive fixed in the groove 521 provided on the contact surface 520b is easily scraped off from the contact surface 520b, and the effect of suppressing the growth of the fixed object is improved. In this respect, the above embodiment is preferable.

  In the above embodiment, the maximum width of the top surface 515a in the axial direction of the developing roller 510 (the width Lmax shown in FIG. 13) is based on the average value of the distances between the grooves in the plurality of grooves 521. It was decided to be big. However, it is not limited to this, For example, the magnitude | size of the said maximum width may be below the average value of the said distance between groove parts. However, in the above embodiment, there is a high possibility that the groove portion 521 faces the convex portion 515 when the developing roller 510 rotates. That is, although there is variation in the distance between the groove portions, the convex portion 515 having the top surface 515a having a width larger than the average value of the distance between the groove portions is likely to face the groove portion 521. As a result, the external additive in the groove portion 521 is easily dispersed in the groove portion 521 by contacting the convex portion 515. As a result, the effect of suppressing the deposition of the external additive is further improved, and the developing device can perform more appropriate development. In this respect, the above embodiment is more desirable.

  In the above embodiment, the recesses 512 are the first recess 512a and the second recess 512b. The first concave portion 512a and the second concave portion 512b are two types of spiral grooves having different inclination angles with respect to the circumferential direction of the developing roller 510, and intersect with each other to form a lattice shape. However, the present invention is not limited to this. For example, the recess 512 may not be a groove. Moreover, when the recessed part 512 is a groove | channel, it does not need to be helical. In addition, only one of the first recess 512a and the second recess 512b may be provided.

  Moreover, in the said embodiment, the convex part 515 has the square top surface 515a enclosed by the 1st recessed part 512a and the 2nd recessed part 512b, and one of the two diagonal lines which this top surface 515a has ( The other is along the axial direction (circumferential direction) of the developing roller 510, but is not limited thereto. Regarding the shape of the top surface 515a, for example, other variations as shown in FIGS. 19A to 19C are also conceivable. 19A to 19C are diagrams showing other variations of the shape of the top surface 515a, and each figure shows the maximum width Lmax of the top surface 515a in the axial direction of the developing roller 510 as reference information. Has been.

  As shown in FIG. 19A, the top surface 515a may be, for example, a diamond that is not square. Further, when the top surface 515a is a square, both of the two diagonals of the top surface 515a do not follow the axial direction and the circumferential direction, and as shown in FIG. 19B, the top surface 515a One side may be along the axial direction (or circumferential direction). However, when the top surface 515a shown in FIG. 19B is formed, a region in which the concave portion 512 continues in the circumferential direction by the circumferential length of the developing roller 510 is formed in the central portion 510a of the developing roller 510. And the groove part 521 arrange | positioned in the position facing the said area | region does not oppose the convex part 515, and the external additive in this groove part 521 will become difficult to disperse | distribute. On the other hand, when one of the two diagonal lines is along the axial direction, the possibility that a region where the recess 512 continues by the circumferential length of the developing roller 510 is reduced. For this reason, each groove part 521 becomes easy to oppose the convex part 515, and the external additive in the said groove part 521 becomes easier to disperse | distribute.

  Furthermore, if one of the two diagonal lines is along the axial direction, the external additive in the groove 521 is moved not only in the longitudinal direction of the groove 521 but also in the width direction of the groove 521. It becomes possible. The movement of the external additive in the groove 521 will be specifically described with reference to FIG. 20A. FIG. 20A is an explanatory view of the movement of the external additive in the certain groove 521 when the convex portion 515 and the certain groove 521 face each other, and shows the surface of the developing roller 510. In the same figure, the certain groove 521 is indicated by a broken line.

  When one of the two diagonal lines of the top surface 515a is along the axial direction, the inclined surfaces 513a and 513b surrounding the top surface 515a are inclined with respect to the circumferential direction. Of the inclined surfaces 513a and 513b, an inclined surface on the downstream side in the rotation direction of the developing roller 510 (for example, an inclined surface 513b indicated by symbol A in FIG. 20A) is a developing roller as shown in FIG. 20A. When facing a certain groove 521 with the rotation of 510, it presses against an external additive (indicated by symbol G in FIG. 20A) collected in the certain groove 521. The external additive moves along the inclined surface 513b by being pushed by the inclined surface 513b. More specifically, the external additive moves in the arrow direction shown in FIG. 20A relative to the inclined surface 513b. That is, the external additive moves in the longitudinal direction of the certain groove 521 that is a direction along the circumferential direction, and also moves in a direction intersecting the circumferential direction, that is, in the width direction of the certain groove 521. As described above, when one of the two diagonal lines on the top surface 515a is along the axial direction, the movement range of the external additive in the groove 521 is expanded. As a result, the external additive is more easily dispersed in the groove portion 521, so that the effect of suppressing the growth of the fixed matter is further improved, and the developing device performs further appropriate development. In this respect, the above embodiment is preferable.

  Furthermore, the top surface may be other shapes than the rhombus, for example, a circle as shown in FIG. 19C.

  In the above embodiment, the pair of inclined surfaces 513a and the second recess 512b included in the first recess 512a and the pair of inclined surfaces included in the second recess 512b while the developing roller 510 rotates in the plurality of grooves 521. A groove portion 521 facing 513b is included. In other words, as described above, the central portion 510a includes a region where four kinds of inclined surfaces 513a and 513b are hung in the circumferential direction, and a groove portion 521 disposed at a position facing the region. To do. However, the present invention is not limited to this. For example, the plurality of groove portions 521 do not include the groove portions 521 facing the regions where the four inclined surfaces 513a and 513b are hung in the circumferential direction. It is good. However, if it is the structure in the said embodiment, it will become possible to disperse | distribute the external additive in the groove part 521 still more easily. Such an effect will be described with reference to FIG. 20A and FIG. 20B described above. FIG. 20B is a view corresponding to FIG. 20A and is a view of the surface of the developing roller 510. That is, the surface shown in FIG. 20B is obtained when the developing roller 510 is slightly rotated from the time when the surface shown in FIG. 20A is seen. In FIG. 20B, a groove portion 521 facing a region where four kinds of inclined surfaces 513a and 513b are applied in the circumferential direction is indicated by a broken line. In addition, the said groove part 521 is the groove part 521 same as the groove part 521 (namely, a certain groove part 521) shown with the broken line in FIG. 20A.

  As described above, an external additive (indicated by symbol G in FIGS. 20A and 20B) in a certain groove 521 is pushed by the inclined surface 513b to which the symbol A is attached in FIG. While moving in the longitudinal direction of 521, it moves to one end side in the width direction of the certain groove 521. Thereafter, as the developing roller 510 rotates, the external additive is disposed at another inclined surface (specifically, at a position facing the groove 521, as shown in FIG. 20B. The inclined surface 513a) to which the symbol B is attached is pushed. Accordingly, the external additive moves relative to the inclined surface 513a in the direction of the arrow in FIG. 20B. That is, the external additive moves to the other end side in the width direction of a certain groove 521. As described above, the external additive collected in the groove portion 521 facing the region where the four inclined surfaces 513a and 513b are applied in the circumferential direction moves in the longitudinal direction of the groove portion 521, It reciprocates in the width direction of the groove 521. As a result, the external additive is more easily dispersed in the groove portion 521, the effect of suppressing the arrangement length of the fixed matter is further improved, and the developing device can perform appropriate development. In this respect, the above embodiment is more desirable.

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

  FIG. 21 is an explanatory diagram showing an external configuration of the image forming system 700. The image forming system 700 includes a computer 702, a display device 704, a printer 706, 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 706, 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. For example, an MO (Magneto Optical) disk drive device or a DVD (Digital Versatile) is used. Disk) etc. may be used.

  Further, 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, the example in which the printer 706 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 a computer 702 and a printer 706, 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 706 may have a part of the functions or mechanisms of the computer 702, the display device 704, the input device 708, and the reading device 710. As an example, the printer 706 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.

FIG. 2 is a diagram illustrating main components constituting the printer. FIG. 2 is a block diagram illustrating a control unit of the printer 10 in FIG. 1. It is a conceptual diagram of a developing device. It is sectional drawing which showed the main components of the image development apparatus. 5 is a perspective view showing a holder 526 in which a developing roller 510, an upper seal 520, and a regulating blade 560 are assembled. FIG. 5 is a perspective view showing a state in which a holder 526 is attached to a housing 540. FIG. FIG. 6 is a diagram illustrating a state in which an upper seal 520 is in contact with a developing roller 510. It is a figure which shows the surface shape by the side of the contact surface 520b of the upper seal 520. FIG. 9A to 9E are views for explaining a manufacturing process of the upper seal 520. FIG. 3 is a schematic perspective view of a developing roller 510. FIG. 2 is a schematic front view of a developing roller 510. FIG. It is the schematic diagram which showed the cross-sectional shape of the 1st recessed part 512a. It is the schematic diagram which showed the cross-sectional shape of the 2nd recessed part 512b. FIG. 12 is an enlarged view of FIG. 11 and shows a first recess 512a, a second recess 512b, and a projection 515. 14A to 14E are schematic views showing the transition of the developing roller 510 in the manufacturing process of the developing roller 510. FIG. 6 is an explanatory diagram for explaining a rolling process of the developing roller 510. FIG. 16A and FIG. 16B are diagrams in which the fixed matter deposited on the contact surface 520b of the upper seal 520 is observed with a laser microscope. It is a schematic diagram for demonstrating that the deposit of a fixed matter is suppressed in this embodiment. It is the figure which showed an example of the variation of the dimension value of the convex part 515, the 1st recessed part 512a, and the 2nd recessed part 512b. 19A to 19C are views showing other variations of the shape of the top surface 515a. 20A and 20B are diagrams for explaining the movement of the external additive in the certain groove portion 521 when the convex portion 515 and the certain groove portion 521 face each other. 1 is an explanatory diagram showing an external configuration of an image forming system 700. FIG.

Explanation of symbols

10 printer, 20 photoconductor, 30 charging unit, 40 exposure unit,
50 YMCK developing unit, 50a central axis, 51 black developing device,
52 magenta developing device, 53 cyan developing device, 54 yellow developing device,
55a, 55b, 55c, 55d holding part, 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, 112 interface, 113 image memory,
510 developing roller, 510a central portion, 510b shaft portion, 512 concave portion,
512a first recess, 512b second recess, 513a, 513b inclined surface,
514 bottom surface, 515 convex portion, 515a top surface, 520 upper seal,
520a outer surface, 520b contact surface, 520c opposite surface, 521 groove,
522 Non-grooved portion, 524 Upper seal biasing member, 526 holder,
526a upper seal support plate, 526b developing roller support plate,
526c regulating blade support plate, 530a, 530b toner container,
540 housing, 542 upper housing part,
544 lower housing part, 545 partition wall, 546 housing seal,
550 toner supply roller, 560 regulating blade, 560a contact portion,
562 rubber part, 564 rubber support part, 564a thin plate, 564b support sheet metal,
564c Longitudinal ends, 564d Short end, 564e Short end,
572 opening, 574 end seal, 576 bearing,
600 pipe material, 602 flange press-fit part, 604 flange,
650 round die, 650a convex portion, 652 round die, 652a convex portion,
700 image forming system, 702 computer, 704 display device,
706 printer, 708 input device, 708A keyboard, 708B mouse,
710 reading device, 710A flexible disk drive device,
710B CD-ROM drive device,
802 internal memory, 804 hard disk drive unit,
900 Base material, 901 sheet, 902 blade

Claims (8)

A developer container having an opening for containing the developer;
A rotatable developer carrying roller provided facing the opening and carrying the developer;
A seal member for contacting the rotating developer carrying roller at a contact surface to prevent leakage of the developer from between the developer carrying roller and the developer container;
A seal member provided on the contact surface with a groove portion whose longitudinal direction intersects with the rotation axis direction of the developer carrying roller;
A developing device comprising: The developing device according to claim 1,
The groove portion is a plurality of groove portions arranged in the rotation axis direction on the contact surface,
2. A developing device according to claim 1, wherein a surface of the developer carrying roller is provided with regularly arranged convex portions and concave portions. The developing device according to claim 2,
The convex portion has a flat top surface surrounded by the concave portion,
The size of the maximum width in the direction along the rotational axis direction of the top surface is:
The arithmetic average value in the plurality of groove portions of the distance from one groove portion of the two adjacent groove portions to the other groove portion,
Larger developing device. The developing device according to claim 3,
The concave portions are spiral first concave portions and second concave portions having different inclination angles with respect to the circumferential direction of the developer carrying roller,
The developing device, wherein the first recess and the second recess intersect each other to form a lattice shape. The developing device according to claim 4,
The top surface is a diamond-shaped top surface surrounded by the first recess and the second recess,
2. A developing device according to claim 1, wherein one of the two diagonal lines on the top surface of the rhombus is along the rotation axis direction. The developing device according to claim 5,
Both the first recess and the second recess are
A flat bottom surface and a pair of inclined surfaces adjacent to the bottom surface and facing each other,
In the plurality of grooves,
A groove portion facing the pair of inclined surfaces each of the first recess and the second recess while the developer carrying roller rotates;
A developing device comprising: A developer container having an opening for containing the developer;
A rotatable developer carrying roller provided facing the opening and carrying the developer;
A seal member for contacting the rotating developer carrying roller at a contact surface to prevent leakage of the developer from between the developer carrying roller and the developer container;
A seal member provided on the contact surface with a groove portion whose longitudinal direction intersects with the rotation axis direction of the developer carrying roller;
An image forming apparatus comprising: a developing device including: Computer and
An image forming apparatus connectable to the computer,
A developer container having an opening for accommodating the developer; a rotatable developer carrying roller provided facing the opening; for carrying the developer; and the rotating developer carrying A seal member for contacting the roller at a contact surface to prevent leakage of the developer from between the developer carrying roller and the developer container, the longitudinal direction of which is the developer A developing device comprising: a seal member provided on the abutting surface with a groove portion intersecting with the rotation axis direction of the support roller;
An image forming system comprising: an image forming apparatus.