JP2011059724A - Developer carrying roller, developing device, image forming apparatus, and image forming system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developing device in which a developer is suitably prevented from leaking. <P>SOLUTION: The developing device is characterized in (c) including: a developer carrying roller (a1) configured to carry the developer and (a2) having a groove formation part having a spiral groove formed on a surface, the depth of the groove being smaller at an end of the groove formation part in an axial direction of the developer carrying roller than at the center part of the groove formation part in the axial direction, and a groove non-formation part disposed outside the groove formation part in the axial direction and having no spiral groove formed; and (b) a seal member coming into contact with the groove non-formation part along a circumferential surface of the developer carrying roller to prevent the developer from leaking. <P>COPYRIGHT: (C)2011,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. Such an image forming apparatus includes, for example, a photoconductor for carrying a latent image and a developing device for developing the latent image carried on the photoconductor by a developer, and from an external device such as a host computer. When an image signal or the like is transmitted, the developing device is positioned at a developing position facing the photosensitive member, and the latent image carried on the photosensitive member is developed with the developer in the developing device to form a developer image. The developer image is transferred to a medium, and finally an image is formed on the medium.

  The developing device includes a developer carrying roller for carrying the developer in order to realize the above-described function of developing the latent image carried on the photoreceptor, and the developer carrying roller. Includes a groove forming portion in which a spiral groove is formed on the surface in order to appropriately carry the developer, and a spiral groove located outside the groove forming portion in the axial direction of the developer carrying roller. And a non-groove forming portion that is not formed.

JP 2003-263018 A JP-A-1-102486

By the way, in the developing device, it is necessary to prevent the developer from leaking from between the peripheral surface of the developer carrying roller and the housing of the developing device. A seal member for preventing leakage of the developer by contacting the non-groove forming portion along the peripheral surface of the developer carrying roller is provided.
However, merely providing such a seal member in the developing device may be insufficient as a countermeasure for preventing leakage of the developer, and it has been demanded that further countermeasures be taken.

  The present invention has been made in view of such problems, and an object of the present invention is to realize a developing device in which leakage of the developer is appropriately prevented.

  The main present invention is (a1) a developer carrying roller for carrying a developer, and (a2) a groove forming portion in which a spiral groove is formed on the surface thereof. A groove forming portion in which the depth of the groove formed in the end portion in the axial direction of the developer carrying roller is smaller than the depth of the groove formed in the central portion in the axial direction of the groove forming portion; A developer-carrying roller having a non-groove forming part that is positioned outside the groove-forming part in the axial direction and in which the spiral groove is not formed; and (b) the developer-carrying roller in the non-groove forming part. A developing device comprising: (c) a seal member that contacts along the peripheral surface of the sheet and prevents leakage of the developer.

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

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. 3 is a schematic perspective view of a developing roller 510. FIG. 2 is a schematic front view of a developing roller 510. FIG. FIG. 6 is a schematic diagram showing a cross-sectional shape of a groove 518. It is the schematic diagram which showed the AA cross section of FIG. 5 is a perspective view of a restriction blade 560. FIG. FIG. 5 is a perspective view of a holder 526. FIG. 5 is a perspective view showing a state where an upper seal 520, a regulating blade 560, and a developing roller 510 are assembled to a holder 526. FIG. 6 is a perspective view showing a state in which a holder 526 is attached to a housing 540. It is a front schematic diagram of the developing roller 510 according to a first modification. It is explanatory drawing for demonstrating the effectiveness of a 1st modification. It is a front schematic diagram of the developing roller 510 according to a second modification. FIGS. 16A to 16E are schematic diagrams showing the transition of the developing roller 510 in the manufacturing process of the developing roller 510. FIGS. FIG. 6 is an explanatory diagram for explaining a rolling process of the developing roller 510. 4 is a flowchart for explaining a method of assembling the yellow developing device 54. 1 is an explanatory diagram showing an external configuration of an image forming system. FIG. 20 is a block diagram illustrating a configuration of the image forming system illustrated in FIG. 19.

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

(A1) a developer carrying roller for carrying a developer, (a2) a groove forming portion having a spiral groove formed on the surface thereof, wherein the developer carrying roller of the groove forming portion The groove formed in the end in the axial direction of the groove is smaller than the depth of the groove formed in the central part in the axial direction of the groove forming part, and the groove in the axial direction. A developer-carrying roller having a non-groove formation part that is located outside the formation part and in which the spiral groove is not formed, and (b) the developer-carrying roller in the non-groove formation part along the peripheral surface And a seal member for preventing leakage of the developer, and (c).
In such a case, a developing device in which leakage of the developer is appropriately prevented is realized.

Next, (a1) a developer carrying roller for carrying the developer, and (a2) a groove forming portion having a spiral groove formed on the surface thereof, the development of the groove forming portion Longitudinal direction of the groove formed at the central portion in the axial direction of the groove forming portion is the acute angle formed by the longitudinal direction of the groove formed in the axial end portion of the agent carrying roller and the axial direction And a groove forming portion larger than an acute angle formed by the axial direction, and a developer-carrying portion that is located outside the groove forming portion in the axial direction and has no spiral groove formed therein. And (b) a seal member for contacting the non-groove forming portion along the peripheral surface of the developer carrying roller to prevent leakage of the developer, and (c). Development device.
In such a case, a developing device in which leakage of the developer is appropriately prevented is realized.

  The groove forming portion may be formed with a first groove and a second groove having different winding directions as the spiral groove.

Next, (a1) a developer carrying roller capable of carrying a developer that is rotatable in a predetermined rotation direction, and (a2) a groove forming portion in which a spiral groove is formed on the surface thereof. A first groove and a second groove having different winding directions are formed as the spiral groove at a central portion in the axial direction of the developer carrying roller of the groove forming portion, and the axial direction of the groove forming portion is A groove forming portion in which only one of the first groove and the second groove is formed at an end of the groove, and the spiral groove located outside the groove forming portion in the axial direction. A developer carrying roller having a non-grooved portion that is not formed; and (b) contacting the non-grooved portion along the circumferential surface of the developer carrying roller to prevent developer leakage. A developing device having (c) a sealing member, and (d) formed at the end portion Of the two directions facing in opposite directions along the longitudinal direction of the groove, the direction in which the direction along the circumferential direction of the developer carrying roller in the direction matches the rotation direction is the first direction. The direction along the axial direction of the developer carrying roller in the first direction coincides with the latter of the direction from the end portion toward the center portion and the direction from the end portion toward the non-groove forming portion. A developing device.
In such a case, a developing device in which leakage of the developer is appropriately prevented is realized.

Further, the surface of the central portion may be plated, but the surface of the end portion may not be plated.
In such a case, it is possible to appropriately prevent leakage of the developer while improving the chargeability of the developer.

The developer may be granular, and the depth of the spiral groove may be not more than twice the volume average particle diameter of the developer.
In such a case, the chargeability of the developer can be improved.

  Further, both the groove and the non-groove portion provided in the central portion may be a developer carrying portion for carrying the developer. A layer thickness regulating member for regulating a layer thickness of the developer carried on the developer carrying roller, wherein a plane of the layer thickness regulating member comes into contact with the developer carrying roller, and the layer It is good also as having the layer thickness control member which controls thickness.

And (a1) a developer carrying roller for carrying the developer, (a2) a groove forming portion having a spiral groove formed on the surface thereof, wherein the developer in the groove forming portion A groove forming portion formed at an end portion in the axial direction of the carrying roller, the groove forming portion being smaller than a groove depth formed at a central portion in the axial direction of the groove forming portion; A developer-carrying roller having a non-groove forming part that is located outside the groove-forming part and in which the spiral groove is not formed; and (b) a peripheral surface of the developer-carrying roller in the non-groove forming part. And a seal member for preventing leakage of the developer, and (d) first grooves having different winding directions as the spiral groove in the groove forming portion. A groove and a second groove are formed, and (e) the surface of the central portion is plated. On the other hand, the surface of the end portion is not plated. (F) The developer is granular, and the depth of the spiral groove is twice the volume average particle diameter of the developer. (G) Both the groove and the non-groove portion provided in the central portion are developer carrying portions for carrying the developer, and (h) carried on the developer carrying roller. A layer thickness regulating member for regulating the layer thickness of the developer, wherein the layer thickness regulating member regulates the layer thickness by abutting a flat surface of the layer thickness regulating member on the developer carrying roller; A developing device characterized by this can also be realized.
In this way, the object of the present invention can be achieved more effectively because most of the effects described above can be achieved.

And (a1) a developer carrying roller for carrying the developer, (a2) a groove forming portion having a spiral groove formed on the surface thereof, wherein the developer in the groove forming portion The acute angle formed by the longitudinal direction of the groove formed in the end portion in the axial direction of the carrying roller and the axial direction is the longitudinal direction of the groove formed in the central portion in the axial direction of the groove forming portion. A developer-carrying roller having a groove forming portion larger than an acute angle formed with the axial direction, and a non-groove forming portion that is located outside the groove forming portion in the axial direction and is not formed with the spiral groove. And (b) a seal member for contacting the non-groove forming portion along the peripheral surface of the developer carrying roller to prevent leakage of the developer, and (c), (d) The groove forming portion includes a first groove and a second groove having different winding directions as the spiral groove. (E) While the surface of the central portion is plated, the surface of the end portion is not plated, (f) the developer is granular, The depth of the spiral groove is not more than twice the volume average particle size of the developer. (G) Both the groove and the non-groove portion provided in the central portion carry the developer. (H) a layer thickness regulating member for regulating the layer thickness of the developer carried on the developer carrying roller, the plane of the layer thickness regulating member being the development surface It is also possible to realize a developing device having a layer thickness regulating member that regulates the layer thickness by coming into contact with the agent carrying roller.
In this way, the object of the present invention can be achieved more effectively because most of the effects described above can be achieved.

(A1) a developer carrying roller for carrying a developer that is rotatable in a predetermined rotation direction, and (a2) a groove forming portion in which a spiral groove is formed on the surface thereof; A first groove and a second groove having different winding directions are formed as the spiral groove at a central portion of the groove forming portion in the axial direction of the developer carrying roller, and the groove forming portion in the axial direction is formed. A groove forming portion in which only one of the first groove and the second groove is formed at the end, and the spiral groove is formed outside the groove forming portion in the axial direction. A developer carrying roller having a non-grooved portion that is not formed, and (b) contacting the non-grooved portion along the peripheral surface of the developer carrying roller to prevent developer leakage. A developing device having a seal member and (c), (d) formed at the end Of the two directions facing in opposite directions along the longitudinal direction of the groove, the direction in which the direction along the circumferential direction of the developer carrying roller in the direction matches the rotation direction is the first direction. The direction along the axial direction of the developer carrying roller in the first direction coincides with the latter of the direction from the end portion toward the center portion and the direction from the end portion toward the non-groove forming portion. (E) While the surface of the central portion is plated, the surface of the end portion is not plated, and (f) the developer is granular and has a spiral shape. The depth of the groove is less than twice the volume average particle diameter of the developer. (G) Both the groove and the non-groove portion provided in the central portion are developed to carry the developer. (H) regulates the layer thickness of the developer carried on the developer carrying roller. A developing device comprising: a layer thickness regulating member for regulating the layer thickness by contacting a flat surface of the layer thickness regulating member with the developer carrying roller Is also feasible.
In this way, the object of the present invention can be achieved more effectively because most of the effects described above can be achieved.

In addition, an image forming apparatus including any one of the developing devices described above can be realized.
In such a case, an image forming apparatus that can appropriately prevent leakage of the developer is realized.

In addition, an image forming system including a computer and an image forming apparatus including any one of the developing devices described above can be realized.
In such a case, an image forming system in which developer leakage is appropriately prevented is realized.

=== Example of Overall Configuration of Image Forming Apparatus ===
Next, an outline of a laser beam printer (hereinafter also 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 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.

  As shown in FIG. 1, the printer 10 according to this embodiment includes a charging unit 30, an exposure unit 40, a YMCK developing unit 50, a primary transfer unit 60, an intermediate transfer body 70, along the rotation direction of the photoconductor 20. A cleaning unit 75, and further, a secondary transfer unit 80, a fixing unit 90, a display unit 95 configured as a liquid crystal panel as a means for notifying a user, and a control for controlling these units and the like and controlling the operation as a printer. A unit 100 is included.

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, a polygon mirror, an F-θ lens, and the like, and charges the modulated laser based on an image signal input from a host computer (not shown) such as a personal computer or a word processor. The irradiated photoconductor 20 is irradiated.

  The YMCK developing unit 50 converts the latent image formed on the photoconductor 20 into toner T as an example of a developer accommodated in the developing device, that is, black (K) toner, magenta accommodated in the black developing device 51. An apparatus for developing using magenta (M) toner contained in the developing device 52, cyan (C) toner contained in the cyan developing device 53, and yellow (Y) toner contained in the yellow developing device 54 It is.

  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 T contained in each developing device 51, 52, 53, 54. The latent images are sequentially developed. 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.
This intermediate transfer body 70 is an endless belt in which a tin vapor deposition layer is provided on the surface of a PET film and a semiconductive paint is formed on the surface layer and laminated. The intermediate transfer body 70 is driven to rotate at substantially the same peripheral speed as the photoconductor 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 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 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 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.

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 (I / F) 112, the unit controller 102 based on a command from the main controller 101. The photosensitive member 20 and the intermediate transfer member 70 are rotated by the control. 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 an 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 in the area by the exposure unit 40. . 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 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 T 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 photosensitive member 20 is scraped off by the cleaning blade 76 supported by the cleaning unit 75 and the toner T adhering to the surface thereof is charged to form the next latent image. Prepare for. The toner T thus scraped off is collected by a residual toner collecting unit 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. The main controller 101 of the control unit 100 is electrically 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. 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.

=== Configuration Example of Developing Device ===
Next, a configuration 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 schematic perspective view of the developing roller 510, and shows a spiral first groove 518a and a second groove 518b having different winding directions. FIG. 6 is a schematic front view of the developing roller 510 and is a diagram showing the positional relationship between the groove forming portion 512 and the non-groove forming portion 514 of the developing roller 510. FIG. 7 is a schematic diagram showing the cross-sectional shape of the groove 518. FIG. 8 is a schematic diagram showing the AA cross section of FIG. 6, and shows the difference between the depth of the groove 518 in the central portion 512a and the depth of the groove 518 in both end portions 512b. FIG. 9 is a perspective view of the regulating blade 560. FIG. 10 is a perspective view of the holder 526. FIG. 11 is a perspective view showing a state in which the upper seal 520, the regulating blade 560, and the developing roller 510 are assembled to the holder 526. FIG. 12 is a perspective view showing that 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 photoconductor 20. Further, in FIGS. 5 to 8, the scales of the grooves 518 and the like are different from the actual ones for easy understanding of the drawings. 7 shows a cross section along the direction indicated by the symbol X in FIG.

  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.

  The yellow developing device 54 includes a developing roller 510 as an example of a developer carrying roller, an upper seal 520, a toner container 530, a housing 540, a toner supply roller 550, a regulating blade 560 as an example of a layer thickness regulating member, and a sealing member. For example, an end seal 574, a holder 526, and the like are included.

  The developing roller 510 carries the toner T and conveys it to a developing position facing the photoconductor 20. The developing roller 510 is a member made of an aluminum alloy, an iron alloy, or the like. As shown in FIGS. 6 and 8, etc., the developing roller 510 is mainly divided into two parts (a groove forming part 512 and a non-groove forming part 514) based on the difference in the structure of the surface thereof.

  The groove forming portion 512 is a portion located in the center in the axial direction of the developing roller 510, and the surface of the groove forming portion 512 is subjected to uneven processing in order to appropriately carry the toner T. In this embodiment, a so-called rolling process (the rolling process will be described in detail in the section of the manufacturing method of the developing device described later) is used as the uneven process, and the groove forming portion 512 is formed by the rolling process. A concave portion and a convex portion are formed on the surface. That is, as shown in FIG. 7, FIG. 8, etc., a groove 518 is formed on the surface of the groove forming portion 512 by rolling, whereby the groove forming portion 512 has a groove 518 as a concave portion and a convex portion. (The groove 518 and the non-groove part 519 both function as a toner carrying part for carrying toner).

  In the present embodiment, as shown in FIGS. 5 and 6, spiral first grooves 518 a and second grooves 518 b having different winding directions are provided as the grooves 518. The magnitude of the acute angle formed by the longitudinal direction of the first groove 518a and the axial direction and the magnitude of the acute angle formed by the longitudinal direction of the second groove 518b and the axial direction are both about 45 degrees. Note that there is a slight difference in the groove 518 and the like between the central portion 512a of the groove forming portion 512 in the axial direction of the developing roller 510 and the end portion 512b (both end portions) in the axial direction.

  In the central part 512a, as shown in FIG. 7, the depth of the groove 518 is about 7 μm. In this embodiment, the toner T is granular (particulate), and the volume average particle diameter of the toner T is about 7 μm. Therefore, the depth of the groove 518 is approximately equal to the size of the volume average particle diameter of the toner T. Are equal. In the central portion 512a, the width of the groove 518 is about 80 μm, and the groove angle (the angle represented by the symbol α in FIG. 7) is about 90 degrees. In addition, the surface of the central portion 512a is subjected to electroless Ni—P plating.

  On the other hand, in the end portion 512b, as shown in FIG. 8, the depth of the groove 518 is smaller than the depth of the groove 518 formed in the central portion 512a (in FIG. Only three grooves 518 are shown as grooves 518 provided in 512b, but in reality, a larger number of grooves 518 are provided in end 512b). In the present embodiment, the depth of the groove 518 formed in the end portion 512b is about half of the depth of the groove 518 formed in the central portion 512a. Moreover, unlike the center part 512a, the electroless Ni-P plating is not given to the surface.

  The non-groove forming portion 514 is a portion where the uneven processing (rolling processing) described above is not performed on the surface and the spiral groove 518 is not formed. The non-groove forming portion 514 is located outside the groove forming portion 512 in the axial direction of the developing roller 510, and the surface thereof is smooth (the ten-point average roughness Rz of the surface is 1 μm or less). Note that, similarly to the end portion 512b, the surface of the non-groove forming portion 514 is not subjected to electroless Ni—P plating.

  Further, the developing roller 510 is provided with a shaft portion 510a. The shaft portion 510a is supported by a developing roller support portion 526b of a holder 526, which will be described later, via a bearing 576 (FIG. 11). 510 is rotatably supported. 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.

  Further, a gap exists 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 housing 540 is manufactured by welding a plurality of integrally formed resin housing parts, that is, the upper housing part 542 and the lower housing part 544, and in order to accommodate the toner T therein. The toner container 530 is formed. The toner containing body 530 has two toner containing portions, that is, a first toner containing portion 530a and a second toner, by a partition wall 545 for dividing the toner T projected 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, and the movement of the toner T is restricted by the partition wall 545 in the state shown in FIG. However, when the YMCK developing unit 50 rotates, the toner accommodated in the first toner accommodating portion 530a and the second toner accommodating portion 530b is once collected on the upper communicating side of the developing position. When returning 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, when the YMCK developing unit 50 rotates, the toner T in the developing device is appropriately agitated.

  For this reason, in this embodiment, the toner container 530 is not provided with a stirring member, but a stirring member for stirring the toner T stored in the toner container 530 may be provided. As shown in FIG. 4, the housing 540 (that is, the first toner storage portion 530 a) has an opening 572 in the lower portion, and the developing roller 510 is provided so as to face the opening 572.

  The toner supply roller 550 is provided in the first toner storage portion 530a described above, supplies the toner T stored in the first toner storage portion 530a to the development roller 510, and remains on the development roller 510 after development. The toner T is peeled off from the developing roller 510. The toner supply roller 550 is made of polyurethane foam or the like, and is in contact with the developing roller 510 in an elastically deformed state. The toner supply roller 550 is disposed below the first toner storage portion 530a, and the toner T stored in the first toner storage portion 530a is transferred by the toner supply roller 550 below the first toner storage portion 530a. Supplied to the developing roller 510. The toner supply roller 550 is rotatable about a central axis, and the central axis is below the rotation central axis of the developing roller 510. Further, 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 upper seal 520 is in contact with the developing roller 510 along the axial direction thereof, allows the toner T remaining on the developing roller 510 after passing through the developing position to move into the housing 540, and the housing 540. The movement of the toner T inside the housing 540 is restricted. The upper seal 520 is a seal made of a polyethylene film or the like. The upper seal 520 is supported by an upper seal support portion 526a of a holder 526, which will be described later, and is provided so that its longitudinal direction is along the axial direction of the developing roller 510 (FIG. 11). The contact position where the upper seal 520 contacts the developing roller 510 is above the central axis of the developing roller 510.

  Further, a malt is formed between a surface of the upper seal 520 opposite to the contact surface 520b that contacts the developing roller 510 (this surface is also referred to as an opposite surface 520c) and the upper seal support portion 526a. An upper seal urging member 524 made of an elastic body such as a plane is provided in a compressed state. The upper seal urging member 524 presses the upper seal 520 against the developing roller 510 by urging the upper seal 520 toward the developing roller 510 with the urging force.

  The regulating blade 560 abuts against the developing roller 510 at the abutting portion 562a from one end to the other end in the axial direction of the developing roller 510 to regulate the layer thickness of the toner T carried on the developing roller 510, In addition, a charge is applied to the toner T carried on the developing roller 510. The regulation blade 560 includes a rubber part 562 and a rubber support part 564 as shown in FIGS. 4 and 9.

The rubber part 562 is made of silicon rubber, urethane rubber, or the like, and is in contact with the developing roller 510.
The rubber support portion 564 includes a thin plate 564a and a thin plate support portion 564b, and supports the rubber portion 562 at one end portion 564d in the short direction (that is, the end portion on the thin plate 564a side). The thin plate 564a is made of phosphor bronze, stainless steel or the like and has a spring property. The thin plate 564a supports the rubber part 562 and presses the rubber part 562 against the developing roller 510 by the biasing force. The thin plate support portion 564b is a metal sheet metal disposed on the other end 564e in the short side direction of the rubber support portion 564, and the thin plate support portion 564b is a side of the thin plate 564a that supports the rubber portion 562. It is attached to the said thin plate 564a in the state which supported the edge on the opposite side.

  The regulating blade 560 is attached to the regulating blade support portion 526c in a state where both longitudinal end portions 564c of the thin plate supporting portion 564b are supported by the regulating blade support portion 526c of the holder 526 described later.

  The end of the regulating blade 560 opposite to the thin plate support portion 564b side, that is, the tip 560a is not in contact with the developing roller 510, and is a portion separated from the tip 560a by a predetermined distance (that is, the contact portion 562a). ) Is in contact with the developing roller 510 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, and the flat surface of the regulating blade 560 comes into contact with the developing roller 510 to regulate the layer thickness. To do. Further, the regulating blade 560 is disposed so that its tip 560a faces the upstream side in the rotation direction of the developing roller 510, and is in contact with a so-called counter. 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. Further, the regulation blade 560 exhibits a function of preventing leakage of the toner T from the toner container 530 by contacting the developing roller 510 along the axial direction thereof.

  Further, as shown in FIG. 11, an end seal 574 is provided on the outer side in the longitudinal direction of the rubber portion 562 of the regulating blade 560. The end seal 574 is formed of a non-woven fabric. The end seal 574 is in contact with the axial end of the developing roller 510, that is, the non-groove forming portion 514, along the peripheral surface of the developing roller 510. The function of preventing leakage of the toner T from between the surface and the housing 540 is exhibited.

  The holder 526 is a metal member for assembling various members such as the developing roller 510, and as shown in FIG. 10, the upper seal support portion along the longitudinal direction (that is, the axial direction of the developing roller 510). 526a, a developing roller support portion 526b provided outside the upper seal support portion 526a in the longitudinal direction (the axial direction), intersecting the longitudinal direction (the axial direction), and intersecting the developing roller support portion, A regulating blade support portion 526c facing the longitudinal end of the upper seal support portion 526a.

  As shown in FIG. 11, the upper seal 520 is supported by the upper seal support portion 526a at the short-side end portion 520a (FIG. 4), and the developing roller 510 is at the end thereof. , And is supported by a developing roller support portion 526b.

  Further, the regulating blade 560 is supported by the regulating blade support portion 526c at both longitudinal end portions 564c thereof. The restriction blade 560 is fixed to the holder 526 by being screwed to the restriction blade support portion 526c.

  As described above, the holder 526 in which the upper seal 520, the developing roller 510, and the regulating blade 560 are assembled prevents the toner T from leaking between the holder 526 and the housing 540 as shown in FIG. It is attached to the housing 540 described above via a housing seal 546 (FIG. 4).

  In the yellow developing device 54 configured as described above, the toner supply roller 550 supplies the toner T stored in the toner container 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 the layer thickness is regulated and electric charge is applied when passing through the contact position. Is done. The toner T on the developing roller 510 to which the layer thickness is regulated and the electric charge is applied reaches the developing position facing the photosensitive member 20 by further rotation of the developing roller 510, and the photosensitive member is subjected to an alternating electric field at the developing position. The latent image formed on 20 is subjected to 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.

=== Effectiveness of Developing Device According to this Embodiment ===
As described above, the developing device according to the present embodiment is a developing roller 510 for carrying toner, and is a groove forming portion 512 having a spiral groove 518 formed on the surface thereof. The depth of the groove 518 formed in the end portion 512b of the portion 512 in the axial direction of the developing roller 510 is greater than the depth of the groove 518 formed in the central portion 512a of the groove forming portion 512 in the axial direction. A developing groove 510 having a smaller groove forming portion 512 and a non-groove forming portion 514 that is located outside the groove forming portion 512 in the axial direction and has no spiral groove 518 formed thereon. An end seal 574 for contacting the forming portion 514 along the peripheral surface of the developing roller 510 and preventing toner leakage is provided. As a result, a developing device or the like in which toner leakage is appropriately prevented can be realized.
That is, as described in the section of the problem to be solved by the invention, in the developing device, it is necessary to prevent the toner from leaking between the peripheral surface of the developing roller 510 and the housing 540 of the developing device. For this purpose, the developing device is provided with an end seal 574 for contacting the non-groove forming portion 514 along the peripheral surface of the developing roller 510 to prevent toner leakage.

However, the provision of such an end seal 574 in the developing device may be insufficient as a measure for preventing toner leakage, and there has been a demand for further measures for preventing toner leakage.
On the other hand, in the present embodiment, of the spiral grooves 518 formed on the surface of the groove forming portion 512, the groove 518 formed in the end portion 512b is replaced with the groove 518 formed in the central portion 512a. Thus, the toner leakage prevention measures are taken. That is, in this example, unlike the conventional example (in which the spiral groove 518 does not change between the central portion 512a and the end portion 512b), the depth of the groove 518 formed in the end portion 512b is the center. Since the depth of the groove 518 formed in the portion 512a is smaller than that in the conventional example, the toner in the groove 518 formed in the end portion 512b is directed toward the non-groove forming portion 514. Thus, the amount of toner moving along the groove 518 is reduced. Therefore, in this example, the amount of toner reaching the end seal 574 in contact with the non-groove forming portion 514 is smaller than in the conventional example, and toner leakage is appropriately prevented. Become.

=== Other measures to prevent toner leakage ===
In the above, as a further measure for preventing the leakage of toner, the groove 518 formed in the end portion 512b of the spiral groove 518 formed on the surface of the groove forming portion 512 is replaced with the groove formed in the central portion 512a. Measures that differ from 518, that is, measures that make the depth of the groove 518 formed in the end portion 512b smaller than the depth of the groove 518 formed in the central portion 512a (this example) have been described. However, this example is an example of a measure for preventing toner leakage by making the groove 518 formed in the end portion 512b different from the groove 518 formed in the central portion 512a, and other examples are also conceivable. In this section, another example (first modification and second modification) of toner leakage prevention measures by making the groove 518 formed in the end portion 512b different from the groove 518 formed in the central portion 512a. ).

<<< About First Modification >>>
First, the first modification will be described with reference to FIGS. 13 and 14. FIG. 13 is a diagram corresponding to FIG. 6 and a schematic front view of the developing roller 510 according to the first modification. FIG. 14 will be described later.

As shown in FIG. 13, in the developing roller 510 according to the first modification, the acute angle formed by the longitudinal direction of the groove 518 formed in the end portion 512b and the axial direction of the developing roller 510 is the central portion 512a. It is larger than the acute angle formed by the longitudinal direction of the groove 518 formed in the axial direction and the axial direction.
More specifically, in the developing roller 510 according to this example described above, there is no difference between the central portion 512a and the end portion 512b with respect to the acute angle formed by the longitudinal direction of the groove 518 and the axial direction. However, in the developing roller 510 according to the first modification, the size of the acute angle formed by the longitudinal direction of the groove 518 formed in the center portion 512a and the axial direction is about 45 degrees. As in the example, the angle is about 45 degrees, whereas the acute angle between the longitudinal direction of the groove 518 formed in the end portion 512b and the axial direction is about 60 degrees (> 45 degrees). .

  As described above, by increasing the acute angle between the longitudinal direction of the groove 518 formed in the end portion 512b and the axial direction, it is possible to appropriately prevent toner leakage. This will be described with reference to FIG. FIG. 14 is an explanatory diagram for explaining the effectiveness of the first modified example. The movement of toner in the vicinity of the boundary 515 between the non-groove forming portion 514 and the end portion 512b (the movement of the toner is indicated by an arrow in FIG. 14). It is a schematic diagram showing. The left diagram of FIG. 14 shows an example when the acute angle is small (45 degrees) (comparative example), and the right diagram of FIG. 14 shows an example when the acute angle is large (60 degrees) (that is, the first deformation). Example).

  The toner in the groove 518 formed in the end portion 512b can move along the groove 518 toward the non-groove forming portion 514, but the groove 518 is not formed in the non-groove forming portion 514. As a result of moving along the groove 518, the toner in the groove 518 that reaches the boundary 515 between the non-groove forming portion 514 and the end portion 512 b comes out of the groove 518. Then, as shown in FIG. 14, the toner coming out of the groove 518 is rebounded to the non-groove forming portion 514 side over the wall 515a positioned at the boundary, and the end portion 512b is bounced back to the wall 515a. The amount of toner that moves to the non-groove forming portion 514 side in the first modified example differs from the acute angle when the first modified example is compared with the comparative example. Due to the above, the amount of toner moving to the non-groove forming portion 514 side in the comparative example is smaller (conversely, the amount of toner moving to the end portion 512b side in the first modified example is The amount of toner that moves toward the end portion 512b in FIG. Therefore, in the first modification, the amount of toner reaching the end seal 574 that is in contact with the non-groove forming portion 514 is smaller than in the comparative example, and toner leakage is appropriately prevented. It will be.

  In the first modified example, the first groove 518a and the second groove 518b having different winding directions are formed as the spiral groove 518 in the groove forming portion 512 as in the present example. It is not limited to this. For example, in this example or the first modification, only one of the first groove 518a and the second groove 518b may be provided.

<<< About the second modification >>>
Next, a second modification will be described with reference to FIG. FIG. 15 is a diagram corresponding to FIG. 6 and a schematic front view of the developing roller 510 according to the second modification. In FIG. 15, first directions to be described later are represented by symbols d1 and d2, and directions along the axial direction of the developing roller 510 in the first directions d1 and d2 are represented by symbols dx1 and dx2. The directions along the circumferential direction of the developing roller 510 in one direction d1, d2 are represented by symbols dy1, dy2, respectively.

  As shown in FIG. 15, in the developing roller 510 according to the second modified example, the first groove 518a and the second groove 518b, which have different winding directions, are formed in the central portion 512a as spiral grooves 518. On the other hand, only one of the first groove 518a and the second groove 518b is formed in the end portion 512b (in FIG. 15, the first groove 518a and the second groove 518b). Of 518b, the groove 518 formed on the end 512b is indicated by a solid line, and the groove 518 not formed on the end 512b is indicated by a broken line).

  More specifically, of the two directions facing the opposite directions along the longitudinal direction of the groove 518 formed in the end portion 512b, the direction along the circumferential direction of the developing roller 510 in the direction is the rotation of the developing roller 510. The direction that coincides with the direction (indicated by symbol r in FIG. 15) is the first direction (in FIG. 15, the first direction relating to the first groove 518a is denoted by d1 and the second direction relating to the second groove 518b). Of the first groove 518a and the second groove 518b, the direction along the axial direction of the developing roller 510 in the first direction d1 and d2 is from the end portion 512b. A direction toward the central portion 512a (the direction is indicated by a symbol X1 in FIG. 15) and a direction toward the non-groove forming portion 514 from the end portion 512b (the direction is indicated by a symbol X2 in FIG. 15) Consistent with the latter of Groove 518 of the direction which there are provided on the end portion 512b.

  More specifically, in the end portion 512b located on the left side in FIG. 15, the direction dx1 along the axial direction of the first direction d1 related to the first groove 518a is a direction from the end portion 512b toward the central portion 512a. X1 and the direction dx2 along the axial direction of the first direction d2 related to the second groove 518b matches the direction X2 from the end portion 512b toward the non-groove forming portion 514. The groove 518 that satisfies the above condition is the second groove 518b. Accordingly, only the second groove 518b of the first groove 518a and the second groove 518b is formed at the end 512b located on the left side in FIG.

  On the other hand, in the end portion 512b located on the right side in FIG. 15, the direction dx1 along the axial direction of the first direction d1 related to the first groove 518a is the same as the direction X2 from the end portion 512b toward the non-groove forming portion 514. In addition, since the direction dx2 along the axial direction of the first direction d2 related to the second groove 518b coincides with the direction X1 from the end portion 512b toward the central portion 512a, the groove satisfying the above-described condition Reference numeral 518 denotes the first groove 518a. Accordingly, only the first groove 518a of the first groove 518a and the second groove 518b is formed at the end 512b located on the right side in FIG.

  When the groove 518 is formed in the end portion 512b in this way, it is possible to appropriately prevent toner leakage. That is, the groove 518 that does not satisfy the above-described conditions (the first groove 518a at the left end 512b in FIG. 15 and the second groove 518b at the right end 512b in FIG. 15 shown by broken lines in FIG. 15). When the developing roller 510 rotates in the rotation direction r, the toner in the groove 518 formed in the end portion 512b is grooved toward the non-groove forming portion 514. The toner moves in the direction opposite to the first direction d1 at the left end 512b in FIG. 15, and the toner moves at the right end 512b in FIG. The direction is opposite to the second direction d2).

  On the other hand, the groove 518 that satisfies the above-described conditions (the second groove 518b at the left end 512b in FIG. 15 and the first groove 518a at the right end 512b in FIG. 15 shown by a solid line in FIG. 15). ) Is formed at the end portion 512b, when the developing roller 510 rotates in the rotation direction r, the toner in the groove 518 formed at the end portion 512b is opposite to the non-groove forming portion 514. The toner moves in the direction opposite to the second direction d2 at the end 512b on the left side in FIG. 15 (that is, toward the center portion 512a). The amount of toner that reaches the end seal 574 that is in contact with the non-groove forming portion 514 is small since the toner moving direction is opposite to the first direction d1 at the right end portion 512b. Na Thing becomes, so that the leakage of the toner is appropriately prevented.

=== Method for Manufacturing Developing Device ===
Next, a method for manufacturing the developing device will be described with reference to FIGS. 16A to 18. FIGS. 16A to 16E are schematic diagrams showing the transition of the developing roller 510 in the manufacturing process of the developing roller 510. FIGS. FIG. 17 is an explanatory diagram for explaining the rolling process of the developing roller 510. FIG. 18 is a flowchart for explaining a method of assembling the yellow developing device 54. When the developing device is manufactured, after the housing 540, the holder 526, the developing roller 510, the toner supply roller 550, the regulating blade 560, etc. are manufactured, the developing device is assembled using these members. To be implemented. In this section, the manufacturing method of the developing roller 510 among the manufacturing methods of these members will be described first, and then the developing device assembly method will be described. In the following description, among the black developing device 51, the magenta developing device 52, the cyan developing device 53, and the yellow developing device 54, the yellow developing device 54 will be described as an example.

<<< About Manufacturing Method of Developing Roller 510 >>>
Here, a method for manufacturing the developing roller 510 will be described with reference to FIGS. 16A to 17.
First, as shown in FIG. 16A, 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. 16B, 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. 16C, the flange 604 is press-fitted into the flange press-fitting 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. 16D, the 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, and the 10-point average roughness Rz of the surface after the centerless polishing is 1.0 μm or less.
Next, as shown in FIG. 16E, a groove 518 is formed by rolling in a portion corresponding to the groove forming portion 512 of the pipe material 600 into which the flange 604 is press-fitted. In the present 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. 17, 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. 17) while being pressed with a symbol P). Protrusions 650 a and 652 a for forming grooves 518 are provided on the surfaces of the round dies 650 and 652, and the grooves 518 are formed in the pipe material 600 by deforming the pipe material 600 with the protrusions 650 a and 652 a. Is formed. In the through-feed rolling, the round dies 650 and 652 rotate, so that the pipe material 600 rotates in the direction opposite to the rotation direction of the round dies 650 and 652 (see FIG. 17). Move in the direction indicated by H. In the portion corresponding to the groove forming portion 512, the first groove 518a of the groove 518 is formed by the convex portion 650a of the round die 650, and the second groove 518b is formed by the convex portion 652a of the round die 652. The Rukoto.

  As described above, in the developing roller 510 according to this embodiment, the depth of the groove 518 is different in the central portion 512a and the end portion 512b of the groove forming portion 512, but through-feed rolling is performed. In this case, the depth of the groove 518 can be varied by changing the pressure P described above (when the depth of the groove 518 is reduced, the pressure P is reduced and the depth of the groove 518 is decreased). In order to increase the thickness, the pressure P may be increased).

  Further, in the developing roller 510 according to the first modification, the acute angle between the longitudinal direction of the groove 518 and the axial direction of the developing roller 510 is different at the central portion 512a and the end portion 512b of the groove forming portion 512. However, the round dies 650 and 652 used when the through feed rolling process is performed in the central portion 512a and the round dies 650 and 652 used when the through feed rolling process is performed in the end portion 512b. By making them different (more specifically, the shapes of the convex portions 650a and 650b are different), the size of the acute angle can be made different.

  Furthermore, in the developing roller 510 according to the second modified example, the first groove 518a and the second groove 518b are formed in the central portion 512a, while the second groove is formed in the left end 512b in FIG. Only the first groove 518a was formed at the right end 512b of FIG. 15 in the case of 518b, while the groove 518 was formed in the central part 512a by both round dies 650 and 652. If the groove 518 is formed only by the round die 652 at the left end 512b in FIG. 15 and the groove 518 is formed by only the round die 650 at the right end 512b in FIG. The developing roller 510 according to the modification can be realized.

  Then, after the rolling process is finished, the surface of the central portion 512a 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.

<<< Assembly Method of Yellow Developing Device 54 >>>
Next, a method for assembling the yellow developing device 54 will be described with reference to FIG.
First, the housing 540, the holder 526, the developing roller 510, the regulating blade 560 and the like described above are prepared (step S2).
Next, the regulating blade 560 is fixed to the holder 526 by screwing the regulating blade 560 to the regulating blade support 526c of the holder 526 (step S4). Note that the end seal 574 described above is attached to the regulating blade 560 in advance before the step S4.
Next, the developing roller 510 is attached to the holder 526 to which the regulating blade 560 is fixed (step S6). At this time, the regulating blade 560 abuts from one end to the other end of the developing roller 510 in the axial direction, and the end seal 574 contacts the non-groove forming portion 514 along the peripheral surface of the developing roller 510. As described above, the developing roller 510 is attached to the holder 526. Note that the above-described upper seal 520 is attached to the holder 526 in advance before the step S6.
Then, the assembly of the yellow developing device 54 is completed by attaching the holder 526 to which the developing roller 510, the regulating blade 560, and the like are attached to the housing 540 via the housing seal 546 (step S8). The toner supply roller 550 described above is previously attached to the housing 540 before step S8.

=== Other Embodiments ===
The developing device and the like according to the present invention have been described above based on the above embodiment. However, the above-described embodiment is intended to facilitate understanding of the present invention and is not intended to limit the present invention. Absent. 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 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, such as a full color laser beam printer, a monochrome laser beam printer, a copying machine, and a facsimile. The present invention can be applied to various image forming apparatuses.

  Also, the photosensitive member is not limited to a so-called photosensitive roller, which is configured by providing a photosensitive layer on the outer peripheral surface of a cylindrical conductive substrate, and is configured by providing a photosensitive layer on the surface of a belt-shaped conductive substrate. A so-called photosensitive belt may be used.

  In the above description, the surface of the central portion 512a is plated, while the surface of the end portion 512b is not plated. However, the present invention is not limited to this. For example, both the surface of the central portion 512a and the surface of the end portion 512b may be plated.

  When the surface of the developing roller 510 is plated, the toner rolling property is improved, so that the toner charging property is improved. However, when the plating is performed not only on the surface of the central portion 512a but also on the surface of the end portion 512b, the end seal 574 for preventing toner leakage comes into contact due to the improvement of the rolling property. In other words, the toner is likely to move to the non-groove forming portion 514 (in other words, it is necessary to seal the toner).

  In the above embodiment, only the former of the surfaces of the central portion 512a and the end portion 512b is plated, and the latter is not plated. Therefore, to the non-groove forming portion 514 while improving the charging property of the toner. By suppressing the movement of the toner, toner leakage can be prevented appropriately. In this respect, the above embodiment is more desirable.

  In the above embodiment, the toner (developer) has a granular shape, and the depth of the spiral groove 518 is not more than twice the volume average particle diameter of the toner (as described above, In the embodiment, the depth of the groove 518 is approximately equal to the volume average particle diameter of the toner), but is not limited thereto. For example, the depth of the groove 518 is the volume average particle diameter of the toner. It is good also as being larger than 2 times.

  When the depth of the groove 518 is less than or equal to twice the volume average particle diameter of the toner, most of the toner positioned between the developing roller 510 and the regulating blade 560 in the groove 518 is mostly developed roller 510 and the regulating blade. Since the toner contacts at least one of 560, the chargeability of the toner becomes appropriate. In this respect, the above embodiment is more desirable. When the depth of the groove 518 is equal to or less than the volume average particle diameter (one time) of the toner, most of the toner positioned between the developing roller 510 and the regulating blade 560 in the groove 518 is developed. This is even more desirable because it contacts both the roller 510 and the regulating blade 560.

  In the above embodiment, the groove 518 and the non-groove portion 519 provided in the central portion 512a are both toner carrying portions for carrying toner. However, the present invention is not limited to this. Absent. For example, only the groove 518 of the groove 518 and the non-groove part 519 may be a toner carrying part.

  In the above-described embodiment, the regulation blade 560 regulates the layer thickness when the flat surface of the regulation blade 560 comes into contact with the developing roller 510. However, the invention is not limited to this. For example, the regulation blade 560 may regulate the layer thickness when the edge of the regulation blade 560 contacts the developing roller 510.

=== 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. 19 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 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.

  FIG. 20 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, 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.

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

  10 laser beam 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 section, 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 shaft portion, 512 groove forming portion, 512a central portion, 512b end 514 Non-groove forming portion, 515 boundary, 515a wall, 518 groove, 518a first groove, 518b second groove, 519 non-groove portion, 520 upper seal, 520a short-side end portion, 520b abutting surface, 520c opposite surface, 524 upper seal urging member, 526 holder, 526a upper seal support part, 526b developing roller support part, 526c regulating blade support part, 530 toner container, 530a first toner container, 530b second toner container, 540 housing, 542 Upper housing portion, 544 Lower housing portion, 545 Partition wall, 546 Housing seal, 550 Toner supply roller, 560 Restriction blade, 560a Tip, 562 Rubber portion, 562a Contact portion, 564 Rubber support portion, 564a Thin plate, 564b Thin plate support Part, 564c Longitudinal direction both ends Part, 564d Short end, 564e Short end, 572 Open, 574 End seal, 576 Bearing, 600 Pipe material, 602 Flange press-fit part, 604 Flange, 650 Round die, 650a Convex part, 652 Round Dice, 652a convex part, 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 inside Memory, 804 hard disk drive unit, T toner.

Claims (13)

(A1) a developer carrying roller for carrying the developer,
(A2) A groove forming portion in which a spiral groove is formed on the surface, and the depth of the groove formed in the end portion of the groove forming portion in the axial direction of the developer carrying roller is A groove forming portion smaller than the depth of the groove formed in the central portion of the groove forming portion in the axial direction;
A developer-carrying roller having a non-groove forming portion that is located outside the groove forming portion in the axial direction and in which the spiral groove is not formed,
(B) a seal member for contacting the non-groove forming portion along the peripheral surface of the developer carrying roller and preventing leakage of the developer;
A developing device comprising (c). (A1) a developer carrying roller for carrying the developer,
(A2) a groove forming portion having a spiral groove formed on the surface thereof, the longitudinal direction of the groove formed at the end of the groove forming portion in the axial direction of the developer carrying roller, and the A groove forming portion having an acute angle formed with an axial direction that is greater than an acute angle formed between a longitudinal direction of the groove forming portion and a longitudinal direction of the groove formed portion at the central portion in the axial direction and the axial direction;
A developer-carrying roller having a non-groove forming portion that is located outside the groove forming portion in the axial direction and in which the spiral groove is not formed,
(B) a seal member for contacting the non-groove forming portion along the peripheral surface of the developer carrying roller and preventing leakage of the developer;
A developing device comprising (c). In the developing device according to claim 1 or 2,
The developing device according to claim 1, wherein a first groove and a second groove having different winding directions are formed as the spiral groove in the groove forming portion. (A1) a developer carrying roller that is rotatable in a predetermined rotation direction and carries a developer,
(A2) A groove forming portion having a spiral groove formed on the surface thereof, and the groove forming portion is formed in the central portion in the axial direction of the developer carrying roller in the winding direction as the spiral groove. A different first groove and a second groove are formed, and a groove forming part in which only one of the first groove and the second groove is formed at an end of the groove forming part in the axial direction; ,
A developer-carrying roller having a non-groove forming portion that is located outside the groove forming portion in the axial direction and in which the spiral groove is not formed,
(B) a seal member for contacting the non-groove forming portion along the peripheral surface of the developer carrying roller and preventing leakage of the developer;
A developing device having (c),
(D) Of the two directions facing in opposite directions along the longitudinal direction of the groove formed at the end, the direction along the circumferential direction of the developer carrying roller in the direction matches the rotation direction Is the first direction,
The direction along the axial direction of the developer carrying roller facing in the first direction coincides with the latter of the direction from the end portion toward the center portion and the direction from the end portion toward the non-groove forming portion. A developing device. The developing device according to claim 1,
2. A developing device according to claim 1, wherein the surface of the central portion is plated, while the surface of the end portion is not plated. The developing device according to any one of claims 1 to 5,
The developer is granular,
2. A developing device according to claim 1, wherein a depth of the spiral groove is not more than twice a volume average particle diameter of the developer. The developing device according to any one of claims 1 to 6,
Both the groove and the non-groove portion provided in the central portion are developer carrying portions for carrying a developer. The developing device according to any one of claims 1 to 7,
A layer thickness regulating member for regulating the layer thickness of the developer carried on the developer carrying roller, wherein a plane of the layer thickness regulating member comes into contact with the developer carrying roller to reduce the layer thickness. Layer thickness regulating member to regulate,
A developing device comprising: (A1) a developer carrying roller for carrying the developer,
(A2) A groove forming portion in which a spiral groove is formed on the surface, and the depth of the groove formed in the end portion of the groove forming portion in the axial direction of the developer carrying roller is A groove forming portion smaller than the depth of the groove formed in the central portion of the groove forming portion in the axial direction;
A developer-carrying roller having a non-groove forming portion that is located outside the groove forming portion in the axial direction and in which the spiral groove is not formed,
(B) a seal member for contacting the non-groove forming portion along the peripheral surface of the developer carrying roller and preventing leakage of the developer;
(C)
(D) In the groove forming portion, a first groove and a second groove having different winding directions are formed as the spiral groove,
(E) While the surface of the central portion is plated, the surface of the end portion is not plated;
(F) The developer is granular, and the depth of the spiral groove is not more than twice the volume average particle diameter of the developer,
(G) The groove and the non-groove part provided in the central part are both developer carrying parts for carrying the developer,
(H) a layer thickness regulating member for regulating the layer thickness of the developer carried on the developer carrying roller, wherein a plane of the layer thickness regulating member comes into contact with the developer carrying roller; A developing device comprising: a layer thickness regulating member that regulates the layer thickness. (A1) a developer carrying roller for carrying the developer,
(A2) a groove forming portion having a spiral groove formed on the surface thereof, the longitudinal direction of the groove formed at the end of the groove forming portion in the axial direction of the developer carrying roller, and the A groove forming portion having an acute angle formed with an axial direction that is greater than an acute angle formed between a longitudinal direction of the groove forming portion and a longitudinal direction of the groove formed portion at the central portion in the axial direction and the axial direction;
A developer-carrying roller having a non-groove forming portion that is located outside the groove forming portion in the axial direction and in which the spiral groove is not formed,
(B) a seal member for contacting the non-groove forming portion along the peripheral surface of the developer carrying roller and preventing leakage of the developer;
(C)
(D) In the groove forming portion, a first groove and a second groove having different winding directions are formed as the spiral groove,
(E) While the surface of the central portion is plated, the surface of the end portion is not plated;
(F) The developer is granular, and the depth of the spiral groove is not more than twice the volume average particle diameter of the developer,
(G) The groove and the non-groove part provided in the central part are both developer carrying parts for carrying the developer,
(H) a layer thickness regulating member for regulating the layer thickness of the developer carried on the developer carrying roller, wherein a plane of the layer thickness regulating member comes into contact with the developer carrying roller; A developing device comprising: a layer thickness regulating member that regulates the layer thickness. (A1) a developer carrying roller that is rotatable in a predetermined rotation direction and carries a developer,
(A2) A groove forming portion having a spiral groove formed on the surface thereof, and the groove forming portion is formed in the central portion in the axial direction of the developer carrying roller in the winding direction as the spiral groove. A different first groove and a second groove are formed, and a groove forming part in which only one of the first groove and the second groove is formed at an end of the groove forming part in the axial direction; ,
A developer-carrying roller having a non-groove forming portion that is located outside the groove forming portion in the axial direction and in which the spiral groove is not formed,
(B) a seal member for contacting the non-groove forming portion along the peripheral surface of the developer carrying roller and preventing leakage of the developer;
A developing device having (c),
(D) Of the two directions facing in opposite directions along the longitudinal direction of the groove formed at the end, the direction along the circumferential direction of the developer carrying roller in the direction matches the rotation direction Is the first direction,
The direction along the axial direction of the developer carrying roller facing in the first direction coincides with the latter of the direction from the end portion toward the center portion and the direction from the end portion toward the non-groove forming portion. ,
(E) While the surface of the central portion is plated, the surface of the end portion is not plated;
(F) The developer is granular, and the depth of the spiral groove is not more than twice the volume average particle diameter of the developer,
(G) The groove and the non-groove part provided in the central part are both developer carrying parts for carrying the developer,
(H) a layer thickness regulating member for regulating the layer thickness of the developer carried on the developer carrying roller, wherein a plane of the layer thickness regulating member comes into contact with the developer carrying roller; A developing device comprising: a layer thickness regulating member that regulates the layer thickness.   An image forming apparatus comprising the developing device according to claim 1.   An image forming system comprising: a computer; and an image forming apparatus including the developing device according to claim 1.

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