JP2018081331A - Electrophotographic image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic image forming apparatus having a drawing member with a photoreceptor drum and a developing unit attached in an apparatus body, where the photoreceptor drum and the developing roller can be separated/contacted from/with each other and the size of the electrophotographic image forming apparatus can be reduced.SOLUTION: There is provided an electrophotographic image forming apparatus including a process cartridge, an apparatus body, and a drawing member 13 that removably supports the process cartridge and can move between an inside position located inside the apparatus body and an outside position located outside the apparatus body, the drawing member 13 includes a contact/separation member 42 that can take a contact position for bringing the developing roller and the photoreceptor drum to be in contact with each other and a separation position for separating the developing roller and the photoreceptor drum from each other.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an electrophotographic image forming apparatus.

  Conventionally, in an image forming apparatus using an electrophotographic image forming process, a photosensitive drum and a developing roller that acts on the photosensitive drum and a developing unit that contains a developer (toner) used for image formation are integrated. A process cartridge system is known. There is also known a developing cartridge system that is a separate body from the photosensitive drum and includes only a developing unit. According to these cartridge systems, the apparatus can be maintained by the user himself / herself without depending on the service person. For this reason, these cartridge systems are widely used in electrophotographic image forming apparatuses.

  There is also known a technique in which drawers for loading process cartridges and developing cartridges are provided, and various drawers can be replaced by pulling out the drawers from the apparatus main body to a predetermined position. According to this technique, the user can easily change the developer.

  Here, when image formation is performed in the image forming apparatus, the developing roller in the developing unit is urged toward the photosensitive drum with a predetermined pressure. In the contact development method in which the developing roller contacts the photosensitive drum and develops, the elastic layer in the developing roller is in contact with the surface of the photosensitive drum with a predetermined pressure.

  Therefore, the elastic layer of the developing roller may be deformed when it is used for a long time with the developing unit mounted on the apparatus main body. As a result, image unevenness may occur during development. Further, since the developing roller is in contact with the photosensitive drum, unnecessary developer may adhere from the developing roller to the photosensitive drum. In addition, since the photosensitive drum and the developing roller are rotated in contact with each other except during development, deterioration of the photosensitive drum, the developing roller, and the developer is promoted by sliding friction between the photosensitive drum and the developing roller. May be.

Therefore, in order to suppress such acceleration of deterioration, a technique has been proposed in which a mechanism for separating the photosensitive drum and the developing roller is provided while image formation is not performed (see Patent Document 1).

  In such a conventional technique, a member (hereinafter referred to as a contact / separation member) capable of taking a position where the photosensitive drum and the developing roller are in contact with each other and a position where they are separated from each other is provided on the apparatus main body side. . When the drawer member (tray) on which the cartridge having the photosensitive drum and the developing roller is mounted enters the apparatus main body, the contact / separation member is located at a position retracted from the movement path of the drawer member. Then, when the door is closed after the drawer member enters the predetermined position in the apparatus main body, the contact / separation member moves toward the cartridge mounted on the drawer member to separate the photosensitive drum from the developing roller.

However, in such a conventional example, the contact / separation member is provided on the apparatus main body side. Therefore, when the drawer member is moved into the apparatus main body, it is necessary to retract the contact / separation member to a position where the movement of the drawer member is not hindered as described above. Further, in order to separate the developing roller from the photosensitive drum, the contact / separation member has to be advanced to the position of the cartridge in the drawer member. Therefore, a space for moving the contact / separation member from the apparatus main body side to the position of the cartridge in the drawer member is required in the apparatus main body. This has been a limitation in terms of downsizing the apparatus main body.

Japanese Patent Laid-Open No. 2007-213024

  SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic image forming apparatus in which a drawer member having a photosensitive drum and a developing unit mounted therein is mounted in the apparatus main body. An object of the present invention is to provide an electrophotographic image forming apparatus.

  The present invention employs the following means in order to solve the above problems.

That is, the image forming apparatus of the present invention is
An electrophotographic photosensitive member, a developing roller for contacting the electrophotographic photosensitive member to develop an electrostatic latent image formed on the electrophotographic photosensitive member, and a developer for supplying the developing roller are accommodated. A process cartridge having a developer container;
The device body;
A support member that removably supports the process cartridge and is movable between an inner position located inside the apparatus main body and an outer position located outside the apparatus main body;
In an electrophotographic image forming apparatus having
A contact / separation member capable of taking a contact position for contacting the developing roller and the electrophotographic photosensitive member and a separation position for separating the developing roller and the electrophotographic photosensitive member is provided on the support member. It is provided.

In addition, other inventions
A developing roller for developing an electrostatic latent image formed on the electrophotographic photosensitive member in contact with the electrophotographic photosensitive member; and a developer accommodating portion for accommodating a developer to be supplied to the developing roller. A developing cartridge having
The device body;
The electrophotographic photosensitive member is supported, the developer cartridge is detachably supported, and is movable between an inner position located inside the apparatus main body and an outer position located outside the apparatus main body. A support member;
In an electrophotographic image forming apparatus having
A contact / separation member capable of taking a contact position for contacting the developing roller and the electrophotographic photosensitive member and a separation position for separating the developing roller and the electrophotographic photosensitive member is provided on the support member. It is provided.

  As described above, according to the present invention, in the electrophotographic image forming apparatus in which the drawer member on which the photosensitive drum and the developing unit are mounted is mounted in the apparatus main body, the photosensitive drum and the developing roller can be contacted and separated. In addition, downsizing can be realized.

FIG. 1 is a schematic cross-sectional view of the entire image forming apparatus according to Embodiment 1 of the present invention. FIG. 2 is a schematic cross-sectional view illustrating a state in which the drawer unit is pulled out in the image forming apparatus according to Embodiment 1 of the present invention. FIG. 3 is a perspective view showing a mounting portion of the drawer member in the apparatus main body of the image forming apparatus according to Embodiment 1 of the present invention. FIG. 4 is a perspective view illustrating a mounting portion of the drawer member in the apparatus main body of the image forming apparatus according to Embodiment 1 of the present invention. FIG. 5 is a perspective view of the drawer unit in the image forming apparatus according to Embodiment 1 of the present invention. FIG. 6 is a perspective view of the drawer unit in the image forming apparatus according to Embodiment 1 of the present invention. FIG. 7 is a schematic sectional view of the process cartridge according to the first embodiment of the present invention. FIG. 8 is a perspective view of the process cartridge according to the first embodiment of the present invention. FIG. 9 is a perspective view showing a state in which the process cartridge according to Embodiment 1 of the present invention is attached to the drawer unit (drawer member). FIG. 10 is a perspective view showing a state where the process cartridge according to the first embodiment of the present invention is mounted on the drawer member. FIG. 11 is a schematic view showing a state in which the process cartridge is mounted on the drawer member. FIG. 12 is a perspective view showing a state in which the drawer unit according to Embodiment 1 of the present invention is mounted in the apparatus main body. FIG. 13 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 1 of the present invention is mounted in the apparatus main body. FIG. 14 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 1 of the present invention is mounted in the apparatus main body and the door is opened. FIG. 15 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 1 of the present invention is mounted in the apparatus main body and the door is closed. FIG. 16 is a perspective view showing a state immediately after the image formation command in the drawer unit according to Embodiment 1 of the present invention. FIG. 17 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 1 of the present invention is mounted in the apparatus main body and the process proceeds to the image forming operation. FIG. 18 is a perspective view showing a state in the middle of shifting to the image forming operation in the drawer unit according to Embodiment 1 of the present invention. FIG. 19 is a schematic cross-sectional view showing a state in the middle of shifting to an image forming operation in the image forming apparatus according to Embodiment 1 of the present invention. FIG. 20 is a perspective view showing a state in the middle of shifting to the image forming operation in the drawer unit according to Embodiment 1 of the present invention. FIG. 21 is a schematic cross-sectional view showing a state in which an image forming operation is enabled in the image forming apparatus according to Embodiment 1 of the present invention. FIG. 22 is a perspective view of a developing cartridge according to Embodiment 2 of the present invention. FIG. 23 is a perspective view of a photoreceptor cartridge according to Embodiment 2 of the present invention. FIG. 24 is a perspective view of the drawer unit in the image forming apparatus according to Embodiment 2 of the present invention. FIG. 25 is a perspective view of the drawer unit in the image forming apparatus according to Embodiment 2 of the present invention. FIG. 26 is a perspective view showing a state in which the photosensitive member cartridge and the developing cartridge according to Embodiment 2 of the present invention are mounted on the drawer member. FIG. 27 is a perspective view showing a state in which the photosensitive member cartridge and the developing cartridge according to Embodiment 2 of the present invention are mounted on the drawer member. FIG. 28 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 2 of the present invention is mounted in the apparatus main body. FIG. 29 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 2 of the present invention is mounted in the apparatus main body. FIG. 30 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 2 of the present invention is mounted in the apparatus main body and the door is opened. FIG. 31 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 2 of the present invention is mounted in the apparatus main body and the door is closed. FIG. 32 is a perspective view showing a state immediately after an image formation command in the drawer unit according to Embodiment 2 of the present invention. FIG. 33 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 2 of the present invention is mounted in the apparatus main body and the process proceeds to the image forming operation. FIG. 34 is a schematic cross-sectional view showing a state in the middle of shifting to an image forming operation in the image forming apparatus according to Embodiment 2 of the present invention. FIG. 35 is a schematic cross-sectional view showing a state in the middle of shifting to the image forming operation in the image forming apparatus according to Embodiment 2 of the present invention. FIG. 36 is a schematic cross-sectional view showing a state in which an image forming operation is enabled in the image forming apparatus according to Embodiment 2 of the present invention. FIG. 37 is a perspective view showing the drawer unit mounting portion in the main assembly of the image forming apparatus according to Embodiment 3 of the present invention. FIG. 38 is a perspective view of the drawer unit in the image forming apparatus according to Embodiment 3 of the present invention. FIG. 39 is a schematic cross-sectional view of the drawer unit in the image forming apparatus according to Embodiment 3 of the present invention. FIG. 40 is a perspective view showing a state when the developing cartridge is attached to the drawer member in the image forming apparatus according to Embodiment 3 of the present invention. FIG. 41 is a schematic cross-sectional view illustrating a state in which the developing cartridge is mounted in the image forming apparatus according to Embodiment 3 of the present invention and the image forming operation is not performed. FIG. 42 is a schematic cross-sectional view illustrating a state where the positioning of the developing cartridge in the image forming apparatus according to Embodiment 3 of the present invention is completed (a state where image formation is possible).

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be exemplarily described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. .

Example 1
An electrophotographic image forming apparatus (hereinafter referred to as an image forming apparatus) according to a first embodiment of the present invention will be described with reference to FIGS.

<Overall configuration of image forming apparatus>
The overall configuration of the image forming apparatus according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic cross-sectional view of the entire image forming apparatus according to Embodiment 1 of the present invention. FIG. 2 is a schematic cross-sectional view illustrating a state in which the drawer unit is pulled out in the image forming apparatus according to Embodiment 1 of the present invention.

  The image forming apparatus 100 according to the present exemplary embodiment includes four electrophotographic photosensitive drums (hereinafter referred to as “photosensitive drum 1”) arranged side by side in the horizontal direction. These photosensitive drums 1 are configured to rotate clockwise in FIG. 1 by driving means (not shown).

Further, in the image forming apparatus 100, as the electrophotographic image forming process means, in addition to the photosensitive drum 1, the charging means 2, the scanner unit 3, the developing units 4y, 4m, 4c, 4k, and the electrostatic transfer means 5 are used. Etc. are provided. “Developing units 4y, 4m, 4c, 4”
k ”(y means yellow, m means magenta, c means cyan, k means that black developer is accommodated). This is referred to as “developing unit 4”.

  Here, the charging unit 2 has a function of uniformly charging the surface of the photosensitive drum 1. The scanner unit 3 has a function of irradiating the photosensitive drum 1 with a laser beam based on image information to form an electrostatic latent image on the surface of the photosensitive drum 1. The developing unit 4 has a function of developing the electrostatic latent image formed on the surface of the photosensitive drum 1 using toner as a developer. The electrostatic transfer unit 5 has a function of transferring a toner image on the photosensitive drum 1 to a sheet material S as a recording medium. Specific examples of the sheet material S include paper, an OHP sheet, and cloth.

  Further, the image forming apparatus 100 is provided with a cleaning unit 6 that removes toner remaining on the surface of the photosensitive drum 1 after transfer. Further, the image forming apparatus 100 includes a cleaning unit that cleans residual toner adhering to the transfer belt 11 below the electrostatic transfer belt (hereinafter referred to as “transfer belt 11”) constituting the electrostatic transfer unit 5. 7 is also provided.

  The photosensitive drum 1 is obtained by, for example, coating an organic optical conductor layer (OPC photosensitive member) on the outer peripheral surface of an aluminum cylinder. Both ends of the photosensitive drum 1 are rotatably supported by a support member (not shown). A drum coupling (not shown) is arranged at one end to receive a driving force from a drive motor (not shown). Thereby, the driving force of the driving motor is transmitted to the photosensitive drum 1 through the drum coupling, and rotates in the clockwise direction in FIG.

  The charging means 2 according to the present embodiment employs a contact charging type. More specifically, the charging means 2 is a conductive roller formed in a roller shape, and this roller is brought into contact with the surface of the photosensitive drum 1. The surface of the photosensitive drum 1 is uniformly charged by applying a charging bias voltage to the roller.

  The scanner unit 3 is disposed on the upper side of the photosensitive drum 1. In the scanner unit 3, image light (laser beam) corresponding to an image signal is irradiated from a laser diode (not shown) to expose the surface of the charged photosensitive drum 1. As a result, an electrostatic latent image corresponding to the image signal is formed on the surface of the photosensitive drum 1.

  Each developing unit 4 includes toner containers 41y, 41m, 41c, and 41k that store yellow, magenta, cyan, and black toners, respectively. The toner containers 41y, 41m, 41c, and 41k are developer storage portions that store a developer (toner) to be supplied to the developing roller 40. The toner in the toner containers 41 y, 41 m, 41 c, 41 k is sent to the toner supply roller 43. Then, the toner is applied to the outer periphery of the developing roller 40 by the toner supply roller 43 and the developing blade 44 pressed against the outer periphery of the developing roller 40, and an electric charge is applied to the toner.

  Then, by applying a developing bias to the developing roller 40, toner adheres to the latent image formed on the photosensitive drum 1 and a toner image is formed. The developing roller 40 is disposed so as to face and contact the photosensitive drum 1. Here, the developing unit 4 and the photosensitive drum 1 integrally form a process cartridge P (Py, Pm, Pc, Pk). The process cartridge P can be replaced together with the process cartridge P when the toner is consumed due to use by the user and the life of the process cartridge P is reached (so-called cartridge system).

  As shown in FIG. 1, the image forming apparatus 100 is provided with a transfer belt 11 in contact with the photosensitive drum 1. Then, the sheet material S is conveyed to the transfer position by the transfer belt 11, and the toner image formed on the surface of the photosensitive drum 1 is transferred.

  Inside the transfer belt 11, transfer rollers 12 are provided at positions facing the respective photosensitive drums 1. A positive charge is applied from these transfer rollers 12 to the sheet material S via the transfer belt 11. As a result, the toner image on the photosensitive drum 1 is transferred to the sheet material S.

  In addition, the image forming apparatus 100 includes a feeding unit 16 having a function of feeding the sheet material S to the image forming unit. The feeding unit 16 is provided with a feeding cassette 17 that stores a plurality of sheet materials S. At the time of image formation, the feeding roller 18 and the registration roller pair 19 rotate according to the image forming operation. Thereby, the sheet material S in the cassette 17 is fed one by one. Then, in synchronization with the rotation of the transfer belt 11 and the toner image, the sheet material S is sent to the transfer belt 11 by the registration roller pair 19.

  Further, the image forming apparatus 100 is provided with a fixing unit 20 having a function of fixing a plurality of color toner images transferred to the sheet material S. The fixing unit 20 includes a rotating heating roller 21b and a pressure roller 21a that presses the heating roller 21b. That is, the sheet material S on which the toner image on the photosensitive drum 1 is transferred is conveyed while being sandwiched between the heating roller 21b and the pressure roller 21a, and at that time, heat and pressure are applied. As a result, toner images of a plurality of colors are fixed on the surface of the sheet material S.

  The image forming process is briefly summarized as follows. When the image forming operation is started, the photosensitive drum 1 rotates. Then, the charging unit 2 applies a uniform charge to the surface of the photosensitive drum 1, and the scanner unit 3 exposes the surface of the photosensitive drum 1 according to the image signal, and the surface of the photosensitive drum 1. An electrostatic latent image is formed thereon. The developing roller 40 develops the electrostatic latent image (attaches toner).

  On the other hand, on the sheet material S fed by the feeding unit 16 and conveyed by the transfer belt 11, the surface of each photoconductive drum 1 is caused by an electric field formed between each photoconductive drum 1 and the transfer roller 12. The toner images thus formed are sequentially transferred. The sheet material S to which the four color toner images are transferred is sent to the fixing unit 20. Then, the sheet material S on which the color image is fixed by the fixing unit 20 is discharged from the discharge unit 24 to the outside of the apparatus by the discharge roller pair 23.

<Outline of drawer member (support member)>
The drawing member 13 as a support member configured to support the process cartridge P so as to be removable and move between an inner position located inside the apparatus main body and an outer position located outside the apparatus main body will be described. To do.

  Here, in this embodiment, the “apparatus main body” means at least the drawer member 13 and the members (fixed to or removable from the drawer member 13) among the various members (parts) constituting the image forming apparatus 100. Means parts other than parts.

  As shown in FIG. 2, the drawer member 13 is provided so as to be able to move (push / draw) linearly in a substantially horizontal direction (arrow D1, D2 direction) with respect to the apparatus main body. The drawer member 13 can be moved to a position housed inside the apparatus main body (position shown in FIG. 1) or a position drawn out of the apparatus main body (position shown in FIG. 2).

Then, in a state where the drawer member 13 is in the drawer position, the process cartridge P (P
y, Pm, Pc, Pk) are attached to the drawer member 13 by the user substantially in the direction of gravity (the direction of arrow C in FIG. 2). The process cartridge P thus mounted is arranged such that its longitudinal direction (the axial direction of the developing roller 40) is perpendicular to the moving direction of the drawer member 13. The four process cartridges Py, Pm, Pc, and Pk are arranged side by side in the moving direction of the drawer member 13.

  These process cartridges P are moved into the apparatus main body together with the drawer member 13 while being attached to the drawer member 13. When the door 10 is closed with the drawer member 13 moved into the apparatus main body, all the process cartridges P are mounted at predetermined positions in the apparatus main body.

  As described above, according to the image forming apparatus 100 according to the present embodiment, the four process cartridges P can be mounted together in the apparatus main body, and the four process cartridges P can be combined together outside the apparatus main body. Can be pulled out. Therefore, the workability at the time of exchanging the process cartridge P is superior to that using a configuration in which the process cartridge is individually mounted in the apparatus main body.

<Mounting part of drawer member (support member)>
In particular, with reference to FIGS. 3 and 4, the configuration of the mounting portion of the drawer member 13 in the apparatus main body will be described. 3 and 4 are perspective views showing a mounting portion of the drawer member in the apparatus main body of the image forming apparatus according to Embodiment 1 of the present invention. 3 and 4, the scanner unit 3 and the like are omitted from the members (parts) constituting the apparatus main body so that the configuration of the mounting portion can be easily understood. 3 and 4 are perspective views seen from different directions.

  A pair of guide portions 14R and 14L for guiding the moving direction of the drawer member 13 are provided on the inner wall surface of the apparatus main body frame so as to face each other. These guide portions 14R and 14L are portions that guide guided portions 13a, 13b, 13c, and 13d (see FIGS. 5 and 6) of the drawer member 13 described later, and have a U-shaped cross section. . Further, these guide portions 14R and 14L can guide from the vicinity of the entrance of the apparatus body (near the door 10) to the back side so that the drawer member 13 can be guided from the position where the drawer member 13 is pulled out to the position inside the apparatus body. It is provided so as to extend in a substantially horizontal direction.

  Further, above the guide portions 14R and 14L, pressing members 65 and 66 for pressing and positioning the process cartridge P to a predetermined position are provided. These pressing members 65 and 66 are configured to press the process cartridge P by moving downward by a driving force from the apparatus main body, and position the process cartridge P at a predetermined position in the apparatus main body. Is provided to do.

As shown in FIG. 4, below the guide portion 14 </ b> L, a drum coupling member 25 for transmitting driving to the photosensitive drum 1 and a developing coupling member 26 for transmitting driving to the developing roller 40. Are arranged at equal intervals in the horizontal direction. The drum coupling member 25 and the development coupling member 26 transmit driving force from a driving source (not shown) to the process cartridge P. When the door 10 is opened, the drum coupling member 25 and the developing coupling member 26 are retracted into the side wall, and enter the process cartridge P side in conjunction with the operation of closing the door 10. ing.

  Further, as shown in FIG. 4, a driving gear 46 that provides a driving force for moving a contact / separation member 42 described later is provided on the back side of the guide portion 14 </ b> L.

<Details of drawer member (support member)>
In particular, the drawer member 13 will be described in detail with reference to FIGS. 5 and 6. 5 and 6 are perspective views of the drawer unit in the image forming apparatus according to Embodiment 1 of the present invention. 5 and 6 are perspective views seen from different directions.

  Guided portions 13a, 13b, 13c, and 13d that are guided by the guide portions 14R and 14L of the apparatus main body are provided at the four corners of the drawer member 13. The guided portions 13a and 13c are guided by the guide portion 14R, and the guided portions 13b and 13d are guided by the guide portion 14L. The guided portions 13a and 13b are configured to protrude outward on the side surface side, and are configured to extend in the pull-out direction so that the pull-out member 13 does not tilt at the pull-out position. The guided portions 13c and 13d are formed in a columnar shape, and are configured to protrude outward on the side surface side.

  Further, at one end portion of the drawer member 13, a handle portion 28 is provided for the user to operate the drawer unit U1.

Further, the drawer member 13 is provided with a mounting portion 13f for mounting a process cartridge P described later in a line. A partition plate 13g is provided between the mounting portions 13f, which serves as a guide when the process cartridge P is mounted. Openings 13e are provided at the bottom of each mounting portion 13f. The photosensitive drum 1 provided in the process cartridge P can come into contact with the transfer belt 11 through these openings 13e.

  Guide portions 13h, 13i, 13j, and 13k for mounting the process cartridge P in the drawer member 13 are provided on one end side and the other end side of each mounting portion 13f. Positioning portions 13h1 and 13j1 for positioning the process cartridge P with respect to the drawer member 13 are provided below the guide portions 13h and 13j.

  As shown in FIG. 5, the drawer member 13 is provided with an opening 13m through which the above-described drum coupling member 25 enters, and an opening 13l through which the development coupling member 26 enters. The drum coupling member 25 and the developing coupling member 26 enter the opening 13m and the opening 13l in conjunction with the operation of closing the door 10. The drum coupling member 25 and the developing coupling member 26 that have entered the openings 13m and 13l are engaged with the coupling member of the process cartridge P, and the drive to the process cartridge P can be transmitted. .

  A contact / separation member 42 is provided on one side of the drawer member 13. The contact / separation member 42 has a shape extending along the moving direction of the drawer member 13 and is configured to be movable in the same direction as the movement direction of the drawer member 13 (the arrow D direction in FIG. 5). The rear end side of the contact / separation member 42 receives a driving force from the drive gear 46 (see FIG. 4) and receives a driving force for moving the contact / separation member 42 as a rack portion 42a as a driving force receiving portion. Is provided.

  The contact / separation member 42 has a concavo-convex shape (first convex portion (force applying portion) 42b, second convex portion (force applying portion) 42c, concave portion 42d) along the longitudinal direction thereof. The first convex portion (force applying portion) 42 b provided on the contact / separation member 42 has a function of separating the photosensitive drum 1 from the transfer belt 4. Further, the second convex portion (force imparting portion) 42 c has a configuration that protrudes further than the first convex portion 42 b, and has a function of separating the developing roller 40 from the photosensitive drum 1. Details will be described later. Between the 1st convex part 42b and the 2nd convex part 42c, the recessed part 42d dented from these convex parts is provided.

  As described above, the drawer unit U1 includes the drawer member 13 and the contact / separation member 42.

<Process cartridge>
Next, the process cartridge P attached to the drawer member 13 will be described with reference to FIGS. FIG. 7 is a schematic sectional view of the process cartridge according to the first embodiment of the present invention. FIG. 8 is a perspective view of the process cartridge according to the first embodiment of the present invention. FIG. 9 is a perspective view showing a state in which the process cartridge according to Embodiment 1 of the present invention is attached to the drawer unit (drawer member).

The process cartridge P includes a photoconductor unit 8 and a developing unit 4. The photosensitive unit 8 includes a photosensitive drum 1, a charging unit 2, and a cleaning unit 6.
And a waste toner container 30 for storing the toner removed by the cleaning means 6. The developing unit 4 includes a developing roller 40, a toner supply roller 43, a developing blade 44, and a toner container 41 that stores toner used for image formation.

  As described above, the toner in the toner container 41 is sent to the toner supply roller 43. Then, the toner is applied to the outer periphery of the developing roller 40 by the toner supply roller 43 and the developing blade 44 pressed against the outer periphery of the developing roller 40, and an electric charge is applied to the toner. Then, by applying a developing bias to the developing roller 40 from the apparatus main body, the toner adheres to the latent image formed on the photosensitive drum 1 to form a toner image. After the toner image developed on the photosensitive drum 1 is transferred to the sheet material S, the toner remaining on the surface of the photosensitive drum 1 is removed by the cleaning unit 6 and stored in the waste toner container 30.

  Here, when the toner in the toner container 41 is consumed, the user can perform printing again by replacing the process cartridge P.

  As shown in FIG. 8, at one end of the process cartridge P, a coupling member 47 for receiving a driving force from the drum coupling member 25 on the apparatus main body side is rotatably supported. A coupling member 45 for receiving a driving force from the developing coupling member 26 is also rotatably supported.

The coupling member 47 is provided at one end of the photosensitive drum 1, and the photosensitive drum 1 is rotated by the driving force received by the coupling member 47 from the apparatus main body. Further, the driving force received by the coupling member 45 is transmitted to the developing roller 40 and the toner supply roller 43 through an intermediate gear (not shown), and these rotate.

  The outer periphery of the coupling member 45 is covered with a cylindrical rib and forms an engaging portion 71a. The engaging portion 71 a is provided on the side cover 71 fixed to the outside of the toner container 41. The coupling member 45 is configured to be rotatable with respect to the engaging portion 71a. Moreover, as shown in FIG. 9, the engaging part 70a is provided also on the opposite side of the engaging part 71a. Similarly, the engaging portion 70 a is provided on the side cover 70. These engaging portions 71 a and 70 a are both provided in the developing unit 4.

  The waste toner container 30 is provided with holes 30a and 30b for supporting the engaging portions 71a and 70a. The holes 30 a and 30 b provided in the waste toner container 30 are engaged with the engaging portions 71 a and 70 a provided in the developing unit 4 so that the photosensitive unit 8 and the developing unit 4 are coupled. ing.

  Here, the engaging portions 71a and 70a are configured to be movable (rotatable) with respect to the hole portions 30a and 30b, so that the developing unit 4 can move with respect to the photosensitive unit 8. it can. That is, the developing roller 40 is configured to be movable with respect to the photosensitive drum 1.

  A spring 9 as an urging member is provided between the photosensitive unit 8 and the developing unit 4 as shown in FIGS. The spring 9 presses the developing roller 40 against the photosensitive drum 1 with a predetermined pressure. When the developing unit 4 moves relative to the photosensitive unit 8 so that the developing roller 40 moves away from the photosensitive drum 1, the developing unit 4 moves against the urging force of the spring 9.

  As shown in FIG. 8, the outer periphery of the coupling member 47 is covered with a cylindrical rib, forming a guided portion 30c. Further, as shown in FIG. 9, a guided portion 30d formed of a cylindrical protrusion is provided on the opposite side of the guided portion 30c in the longitudinal direction. Further, as shown in FIG. 8, a guided portion 30e is provided above the guided portion 30c, and a guided portion 30f is provided above the guided portion 30d as shown in FIG. ing. These guided portions 30 c, 30 d, 30 e, and 30 f have functions for mounting the process cartridge P in the drawer member 13 and positioning the process cartridge P in the drawer member 13. Details will be described later.

  Further, as shown in FIG. 8, a force receiving portion 30 g that protrudes outward in the axial direction of the photosensitive drum 1 is provided at the upper portion on one side of the photosensitive unit 8. The force receiving portion 30 g has a function of separating the photosensitive drum 1 from the transfer belt 11 by receiving a force from the contact / separation member 42 provided on the drawer member 13. Details will be described later. Further, as shown in FIG. 9, a force receiving portion 30 h is provided at the upper portion on the other side of the photosensitive unit 8. Each of these force receiving portions 30g and 30h has a function of positioning the process cartridge P within the drawer member 13 by receiving force from pressing members 65 and 66 described later.

  Further, as shown in FIG. 8, a force receiving portion 71 b protruding outward in the axial direction of the developing roller 40 is provided above the side cover 71 of the developing unit 4. The force receiving portion 71 b has a function of receiving a force from the contact / separation member 42 and separating the developing roller 40 from the photosensitive drum 1. Details will be described later.

<Attaching the process cartridge to the drawer member>
Mounting of the process cartridge P (Py, Pm, Pc, Pk) on the drawer member 13 will be described with reference to FIGS. 9 and 10 are perspective views showing a state in which the process cartridge according to Embodiment 1 of the present invention is mounted on the drawer member. FIG. 9 and FIG. 10 (a) both show the process cartridge mounting process, and are views seen from different directions. FIG. 10B shows a state where all process cartridges are mounted. FIG. 11 is a schematic view showing a state in which the process cartridge is mounted on the drawer member. In addition, Fig.11 (a) is the schematic seen from the side, The figure (b) is typical (vertical) sectional drawing.

  The process cartridges Py, Pm, Pc, and Pk are mounted on four mounting portions 13f (see FIG. 5) provided on the drawer member 13, respectively. The user mounts the process cartridge P in the direction of arrow C, which is substantially the direction of gravity.

When mounting the process cartridge P, the user first mounts the guided portions 30c and 30d provided at both ends of the process cartridge P along the guide portions 13h and 13j of the drawer member 13. Next, the user mounts the guided portions 30e and 30f along the guides 13i and 13k. As a result, the process cartridge P is guided by the guide portions 13h, 13i, 13j, and 13k and mounted in the drawer member 13.

  When the process cartridge P is attached to the drawer member 13, the force receiving portion 30 g provided in the photosensitive unit 8 comes into contact with the first convex portion 42 b provided in the contact / separation member 42. Further, the force receiving portion 71b provided on the side cover 71 of the developing unit 4 contacts the second convex portion 42c.

  When the force receiving portion 30g provided in the photoconductor unit 8 contacts the first convex portion 42b, the process cartridge P is held at a position one step higher than the position where image formation is performed. That is, as shown in FIG. 2, the surface of the photosensitive drum 1 is held at a position that is one step higher (separated) than the surface of the transfer belt 11 (recording medium conveyance surface).

  Here, the contact / separation member 42 is provided only on one end side of the drawer member 13. A force receiving portion 30 g that receives a force from the first convex portion 42 b of the contact / separation member 42 is also provided only on one side of the photosensitive unit 8. However, since the guided portion 30 d provided on the other end side of the process cartridge P is provided outside the end in the width direction of the transfer belt 11, the surface of the photosensitive drum 1 is separated from the surface of the transfer belt 11. It is possible to leave. That is, the process cartridge P floats when the force receiving portion 30g receives the force from the first convex portion 42b on one end side. On the other hand, on the other end side, the guided portion 30d is kept in contact with the positioning portion 13j1 of the drawer member 13. Therefore, the process cartridge P is inclined with respect to the transfer belt 11. However, as described above, the guided portion 30 d is provided outside the end in the width direction of the transfer belt 11, so that the surface of the photosensitive drum 1 is separated from the surface of the transfer belt 11.

  Further, the surface of the developing roller 40 is separated from the surface of the photosensitive drum 1 by the force receiving portion 71 b provided in the developing unit 4 contacting the second convex portion 42 c provided in the contacting / separating member 42. This will be described in particular with reference to FIG.

  The 2nd convex part 42c provided in the contacting / separating member 42 is comprised so that it may become one step higher than the 1st convex part 42b. On the other hand, the force receiving portion 30g provided in the photoconductor unit 8 and the force receiving portion 71b provided in the developing unit are configured to have substantially the same height without receiving external force. Therefore, the force receiving portion 71b that is in contact with the second convex portion 42c receives the force corresponding to the weight of the developing unit 4 and thereby exposes the surface of the developing roller 40 to resist the force of the urging member 9. Separated from the surface of the body drum 1. That is, when the force receiving portion 71 b receives the force, the engaging portions 71 a and 70 a provided in the developing unit 4 rotate around the holes 30 a and 30 b provided in the photosensitive unit 8, respectively.

  At this time, the contact / separation member 42 is in a position where the first convex portion 42b contacts the force receiving portion 30g and the second convex portion 42c contacts the force receiving portion 71b. At this time, the surface of the photosensitive drum 1 can be positioned at a position separated from the surface of the transfer belt 11. Further, the surface of the developing roller 40 can be positioned at a position separated from the surface of the photosensitive drum 1. In this way, the position when the contact / separation member 42 is at a position where the developing roller 40 and the photosensitive drum 1 can be separated is hereinafter referred to as a “separation position”.

When the drawer member 13 is pulled out from the apparatus main body, that is, when the drawer member 13 is positioned outside the apparatus main body (hereinafter referred to as an outer position as appropriate), the contact / separation member 42 is positioned at the “separation position”. . Therefore, as shown in FIG. 11, when the process cartridge P is mounted on the drawer member 13, the surface of the developing roller 40 is separated from the surface of the photosensitive drum 1 in accordance with the mounting operation. Therefore, when the process cartridge P is mounted on the drawer member 13, it is possible to suppress the surface of the photosensitive drum 1 and the surface of the developing roller 40 from being rubbed due to an impact at the time of mounting and scratching these surfaces.

  As described above, in the process of mounting the process cartridge P on the drawer member 13, the process cartridge P is mounted in a state where the surface of the developing roller 40 is separated from the surface of the photosensitive drum 1. Further, the process cartridge P is mounted in a state where the surface of the photosensitive drum 1 is separated from the surface of the transfer belt 11.

<Mounting the drawer unit in the main unit>
The mounting operation of the drawer unit U1 in the apparatus main body will be described with reference to FIGS. FIG. 12 is a perspective view showing a state in which the drawer unit according to Embodiment 1 of the present invention is mounted in the apparatus main body. FIG. 13 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 1 of the present invention is mounted in the apparatus main body. FIG. 14 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 1 of the present invention is mounted in the apparatus main body and the door is opened. 13 and 14 show a schematic cross-sectional view of the entire apparatus and an enlarged schematic cross-sectional view of the vicinity of one photosensitive drum. FIG. 15 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 1 of the present invention is mounted in the apparatus main body and the door is closed. FIG. 15 shows a state where the image forming operation is not performed.

  As shown in FIG. 12, in the drawer unit U1, guided portions 13a, 13b, 13c, and 13d (see FIGS. 5 and 6) in the drawer member 13 are guided by the guide portions 14R and 14L (see FIGS. 3 and 4) on the apparatus main body side. ) Along the direction of arrow E.

  During the mounting operation of the drawer unit U1 (drawer member 13), the surface of the photosensitive drum 1 and the recording medium transport surface 11a of the transfer belt 11 are kept apart. That is, a gap g is formed between the surface of the photosensitive drum 1 and the recording medium conveyance surface 11 a of the transfer belt 11. Accordingly, the drawer unit U1 can be mounted in the apparatus main body without causing the surface of the photosensitive drum 1 to rub against the surface of the transfer belt 11. During the mounting operation, the drawer unit U1 moves substantially parallel to the recording medium conveyance surface 11a of the transfer belt 11.

  Further, during the mounting operation of the drawer unit U1, the surfaces of the photosensitive drum 1 and the developing roller 40 are also kept separated from each other. That is, a gap h is formed between the two, and the contact / separation member 14 is positioned at the “separation position”. Therefore, when the drawer unit U1 with the process cartridge P mounted therein is mounted in the apparatus main body, the surface of the photosensitive drum 1 and the surface of the developing roller 40 come into contact with each other due to an impact or the like at the time of mounting, and the surface is damaged. Can be suppressed.

  When the drawer unit U1 is mounted in the apparatus main body, the rack portion 42a (see FIG. 10) provided on the contact / separation member 42 and the drive gear 46 (see FIG. 4) of the apparatus main body are engaged with each other. Become. As a result, the driving force can be transmitted from the driving gear 46 to the rack portion 42a.

  As shown in FIG. 14, when the drawer unit U1 is completely inserted into the apparatus main body and the door 10 is opened, the surface of the photosensitive drum 1 and the recording medium conveying surface 11a of the transfer belt 11 are still separated from each other. doing. Similarly, the surfaces of the photosensitive drum 1 and the developing roller 40 are also spaced apart.

FIG. 15 shows a state in which the door is closed. By the operation of closing the door 10, the drum coupling member 25 and the developing coupling member 26 (see FIG. 4) enter the opening 13m and the opening 13l (see FIG. 5) provided in the drawer member 13, respectively. . However, the process cartridge P is not yet positioned at the regular position (position where image formation is possible). Therefore, the drum coupling member 25 and the development coupling member 26 are not engaged with the coupling members 47 and 45 (see FIG. 8), respectively.

  Even when the door 10 is closed, when the image forming operation is not performed, the surface of the photosensitive drum 1, the recording medium conveying surface 11 a of the transfer belt 11, and the surface of the photosensitive drum 1. The surfaces of the developing roller 40 are all kept apart. That is, the contact / separation member 14 is located at the “separation position”.

  In the state as described above, it waits until an image forming operation command is received from the apparatus main body.

<Operation of each part during image forming operation>
The operation of each part during the image forming operation will be described with reference to FIGS. FIG. 16 is a perspective view showing a state immediately after the image formation command in the drawer unit according to Embodiment 1 of the present invention. FIG. 17 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 1 of the present invention is mounted in the apparatus main body and the process proceeds to the image forming operation. FIG. 17 shows a schematic cross-sectional view in the vicinity of the drawer unit and the transfer belt, and an enlarged schematic cross-sectional view in the vicinity of one photosensitive drum. FIG. 18 is a perspective view showing a state in the middle of shifting to the image forming operation in the drawer unit according to Embodiment 1 of the present invention. FIG. 19 is a schematic cross-sectional view showing a state in the middle of shifting to an image forming operation in the image forming apparatus according to Embodiment 1 of the present invention. FIG. 19 shows a schematic cross-sectional view of the entire apparatus and an enlarged schematic cross-sectional view of the vicinity of one photosensitive drum. FIG. 20 is a perspective view showing a state in the middle of shifting to the image forming operation in the drawer unit according to Embodiment 1 of the present invention. FIG. 21 is a schematic cross-sectional view showing a state in which an image forming operation is enabled in the image forming apparatus according to Embodiment 1 of the present invention. FIG. 21 shows a schematic cross-sectional view of the entire apparatus and an enlarged schematic cross-sectional view of the vicinity of one photosensitive drum.

  When an image formation command is received, the drive gear 46 that is drivingly connected to a motor (not shown) provided in the apparatus main body rotates in the direction of arrow F as shown in FIG. As a result, the contact / separation member 42 moves in the direction of arrow G in the figure by the rack portion 42a meshing with the drive gear 46. When the contact / separation member 42 moves to the position shown in FIG. 16, the force receiving portion 30 g provided on the photosensitive unit 8 is disengaged from the first convex portion 42 b of the contact / separation member 42. However, the force receiving portion 71b provided in the developing unit 4 is still located on the second convex portion 42c. The second convex portion 42c is configured to be longer in the moving direction of the contacting / separating member 42 than the first convex portion 42b, thereby enabling such a mechanism.

  FIG. 17 shows the positional relationship among the drawer member 13, the process cartridge P, and the transfer belt 11 in the state shown in FIG. As described above, the surface of the photosensitive drum 1 comes into contact with the surface of the transfer belt 11 by the force receiving portion 30g being detached from the first convex portion 42b by the moving operation of the contact / separation member 42. On the other hand, since the force receiving portion 71b is still receiving the force from the second convex portion 42c, the developing roller 40 is separated from the surface of the photosensitive drum 1. Since the surface of the photosensitive drum 1 and the surface of the developing roller 40 are kept separated from each other, the position of the contact / separation member 42 at this time corresponds to a “separation position”.

Thereafter, as shown in FIG. 18, the pressing members 65 and 66 provided on the apparatus main body side are driven by a driving source (not shown) and moved in the direction of arrow H. The pressing members 65 and 66 abut against the force receiving portions 30g and 30h provided in the process cartridge P, and apply force. As a result, the guided portion 30c (see FIG. 8) of the process cartridge P comes into contact with the positioning portion 13h1 (see FIG. 9) provided on the drawer member 13. Further, the guided portion 30d (see FIG. 9) contacts the positioning portion 13j1 (see FIG. 10). Furthermore, the guided portions 30e and 30f (see FIGS. 8 and 9) fit into the guide portions 13i and 13k (see FIGS. 9 and 10),
The process cartridge P is positioned in the drawer member 13.

  As described above, the process cartridge P is positioned in the apparatus main body by the action of the pressing members 65 and 66.

  FIG. 19 shows the inside of the apparatus main body in the state shown in FIG. In this state, the process cartridge P maintains the state where the surface of the developing roller 40 is separated from the surface of the photosensitive drum 1. Further, the surface of the photosensitive drum 1 is in contact with the surface of the transfer belt 11. Since the surface of the photosensitive drum 1 and the surface of the developing roller 40 are kept separated from each other, the position of the contact / separation member 42 at this time corresponds to a “separation position”.

  Thereafter, in order to bring the developing roller 40 and the photosensitive drum 1 into contact with each other, the drive gear 46 further rotates, and the contact / separation member 42 moves in the arrow G direction as shown in FIG. As a result, the force receiving portion 71b provided in the developing unit 4 is separated from the second convex portion 42c of the contact / separation member 42 and is not in a state of receiving a force from the second convex portion 42c. Accordingly, the surface of the developing roller 40 and the surface of the photosensitive drum 1 are brought into contact with each other by the biasing force of the spring 9 provided between the developing unit 4 and the photosensitive unit 8. As a result, the image forming apparatus 100 becomes ready for image formation. Thus, in order to enable image formation, the position when the contact / separation member 42 is in a position where the surface of the developing roller 40 and the surface of the photosensitive drum 1 can be brought into contact with each other is hereinafter referred to as “contact Referred to as “position”. The image forming operation is as described above. FIG. 21 shows the inside of the apparatus main body when the image forming operation is possible.

  When the image formation is completed, the drive gear 46 is rotated in the direction opposite to the arrow F direction shown in FIG. 16, and the contact / separation member 42 is moved in the arrow I direction in FIG. As a result, the contact / separation member 42 is again moved to the “separation position”, and the surface of the developing roller 40 is separated from the surface of the photosensitive drum 1 (the state shown in FIGS. 18 and 19).

  Thereafter, the pressing members 65 and 66 move in the direction opposite to the pressing direction, and the contact / separation member 42 further moves in the direction of arrow I. As a result, the surface of the photosensitive drum 1 is separated from the surface of the transfer belt 11. In this state, the next image formation command is awaited. Alternatively, when the drawer member 13 is pulled out, the surface of the photosensitive drum 1 and the surface of the transfer belt 11 (recording medium conveying surface 11a), and the surface of the photosensitive drum 1 and the surface of the developing roller 40 remain separated. maintain. That is, the contact / separation member 42 is located at the “separation position”. Therefore, when the drawer member 13 with the process cartridge P mounted is pulled out of the apparatus main body, the surface of the photosensitive drum 1 and the surface of the developing roller 40 come into contact with each other due to an impact during movement, and the surface is damaged. This can be suppressed.

<Excellent points of this embodiment>
As described above, the image forming apparatus 100 according to the present embodiment employs a configuration in which the contact / separation member 42 can take the “separation position” and the “contact position”. Then, by the movement of the contact member 42, a configuration is adopted in which the developing roller 40 is moved to a position where it is separated from the photosensitive drum 1 or a position where it abuts on the photosensitive drum 1 as appropriate. Accordingly, when image formation is not performed, such as during a drawer operation of the drawer unit U1 (drawer member 13), the developing roller 40 and the photosensitive drum 1 can be brought into a non-contact state. Therefore, it is possible to suppress the deterioration of each member and extend the life.

Further, the image forming apparatus 100 according to the present embodiment employs a configuration in which the contact / separation member 42 is provided on the drawer member 13. Therefore, as in the case of the conventional example described above, a configuration in which the contact / separation member enters from the apparatus main body side to the inside of the drawer member is required as in the case where a contact / separation member for separating the developing roller from the photosensitive drum is provided on the apparatus main body side. And not. That is, a space for moving the contact / separation member from the apparatus main body side to the position of the cartridge in the drawer member is not required in the apparatus main body, and thus the apparatus main body can be downsized.

  A contact / separation member fixed on the apparatus main body side is provided, and a force receiving portion provided on the cartridge receives a force from the contact / separation member due to a push-in operation or a pull-out operation of the pull-out member, so A configuration in which the contact / separation operation is performed can also be considered.

  However, even when such a configuration is adopted, in order to allow the force receiving portion provided in the cartridge to contact the contact / separation member, it is necessary to project the force receiving portion to the outside of the drawer member. . Therefore, it becomes an obstacle to downsizing of the apparatus. On the other hand, according to this embodiment, since the contact / separation member 42 is provided in the drawer member 13, it is not necessary to project the force receiving portion 71b more than necessary, and the process cartridge P can be downsized. .

  Even when the above-described configuration is adopted, the cartridge force receiving portion is retracted from the contacting / separating member so that the force receiving portion of the cartridge contacts the contacting / separating member only at a desired timing. The cartridge must be mounted in the state where it is left. Finally, a configuration and mechanism for moving the entire drawing member to a position where the force receiving portion of the cartridge comes into contact with the contact / separation member is required. On the other hand, according to the present embodiment, since the contact / separation member 42 is provided in the drawer member 13, the configuration of the apparatus main body can be simplified and the size can be reduced.

  In this embodiment, as an example of the transfer belt 11, the transfer belt 11 transports the sheet material S to the surface of the photosensitive drum 1 and directly transfers the developed image on the photosensitive drum 1 to the sheet material S. Shown when configured. However, the present invention can also be applied to an image forming apparatus that employs an intermediate transfer belt of a type in which a developed image formed on a photosensitive drum is transferred and finally retransferred to a recording medium (sheet material). .

  In the present embodiment, the configuration in which the contact / separation member 42 is provided only on one end side of the pull-out member 13 is shown. However, a contact / separation member may be similarly provided on the other end side of the drawer member 13. In this case, however, it goes without saying that force receiving portions for receiving force from the contact / separation member also need to be provided on both ends. If contact / separation members are provided on both sides, the process cartridge moves without tilting the axes of the photosensitive drum and the developing roller provided in the cartridge. Therefore, the separation state between the photosensitive drum and the transfer belt and the separation state between the photosensitive drum and the developing roller can be further stabilized.

(Example 2)
22 to 36 show a second embodiment of the present invention. In the first embodiment, when the process cartridge P in which the photosensitive unit 8 including the photosensitive drum 1 and the developing unit 4 including the developing roller 40 are integrated is mounted on the drawer member 13 is employed. An example was explained. In the present embodiment, an example in which a method in which the photosensitive unit including the photosensitive drum 1 and the developing unit including the developing roller 40 are separately attached to the drawer member 63 will be described. Since other configurations and operations are the same as those in the first embodiment, the same components are denoted by the same reference numerals, and the description thereof is omitted as appropriate.

<Development cartridge>
A developing cartridge which is a developing unit according to Embodiment 2 of the present invention will be described with reference to FIG. FIG. 22 is a perspective view of a developing cartridge according to Embodiment 2 of the present invention. In FIGS. 22A and 22B, perspective views viewed from different directions are shown in FIGS.

  The developing cartridge 60 according to this embodiment includes a developing roller 40, a toner supply roller (not shown), a developing blade (not shown), and a toner container 41 that stores toner that is a developer used for image formation. Consists of Note that the image forming apparatus according to the present exemplary embodiment includes four developing cartridges 60 having different toner colors. Therefore, the reference numerals used in the description of the specification and the reference numerals in the drawings are appropriately divided into a case of simply “60” and a case of “60y, 60m, 60c, 60k” for distinction, respectively. ing. In the latter case, y represents yellow, m represents magenta, c represents cyan, and k represents black developer.

  As shown in FIG. 22, at one end of the developing cartridge 60, a coupling member 45 for receiving a driving force from the developing coupling member 26 on the apparatus main body side is rotatably supported. The driving force received by the coupling member 45 is transmitted to the developing roller 40, the toner supply roller, and the like via an intermediate gear (not shown).

  A force receiving portion 61 a that protrudes outward in the axial direction of the developing roller 40 is provided on the upper portion of the side cover 61 on one side surface of the developing cartridge 60. The force receiving portion 61 a has a function of separating the developing roller 40 from the photosensitive drum 1 by receiving a force from the contact / separation member 42 (see FIG. 24 described later). Details will be described later. Further, a force receiving portion 62 a is provided on the upper portion of the side cover 62 on the other side of the developing cartridge 60. These force receiving portions 61 a and 62 a are both pressed by a pressing member provided on the apparatus main body side and have a function of positioning the developing cartridge 60 with respect to the drawer member 63. Details will be described later.

  Positioned portions 61b and 62b are provided on both sides of the force receiving portions 61a and 62a so as to protrude outward in the axial direction of the developing roller 40. Details will be described later.

<Photoreceptor cartridge>
A photoconductor cartridge which is a photoconductor unit according to Embodiment 2 of the present invention will be described with reference to FIG. FIG. 23 is a perspective view of a photoreceptor cartridge according to Embodiment 2 of the present invention. In FIGS. 23A and 23B, perspective views viewed from different directions are shown in FIGS.

  The photoconductor cartridge 50 according to this embodiment includes a photoconductor drum 1, a charging unit 2, a cleaning unit (not shown), and a waste toner container 31 that stores toner removed by the cleaning unit. Note that the image forming apparatus according to the present embodiment includes four photoconductor cartridges 50 arranged on the photoconductor drum 1 so that the color of the toner to be developed is different. Therefore, the reference numerals used in the description of the specification and the reference numerals in the figures are appropriately divided into the case of simply “50” and the case of “50y, 50m, 50c, 50k” for distinction, respectively. ing. In the latter case, y means yellow, m means magenta, c means cyan, and k means that black developer is developed.

  As shown in FIG. 23, a coupling member 47 for receiving a driving force from the drum coupling member 25 on the apparatus main body side is rotatably supported at one end of the photosensitive cartridge 50. The coupling member 47 is provided at one end of the photosensitive drum 1, and the photosensitive drum 1 rotates by the driving force received by the coupling member 47 from the apparatus main body side.

The outer periphery of the coupling member 47 is covered with a cylindrical rib, and forms a guided portion 31a. In addition, a guided portion 31b configured so that a cylindrical protrusion protrudes is also provided on the opposite side of the guided portion 31a. A guided portion 31c is provided above the guided portion 31a, and a guided portion 31d is also provided above the guided portion 31b. These guided portions 31 a, 31 b, 31 c, and 31 d have a function for mounting the photoreceptor cartridge 50 in the drawer member 63 and positioning it in the drawer member 63. Details will be described later.

  In addition, a force receiving portion 31 e that protrudes outward in the axial direction of the photosensitive drum 1 is provided on an upper portion on one side of the photosensitive cartridge 50. The force receiving portion 31 e has a function of separating the photosensitive drum 1 from the transfer belt 11 by receiving a force from a contact / separation member 42 (see FIG. 24 described later) provided on the drawer member 63. Details will be described later. Further, a force receiving portion 31 f is provided on the other side surface side of the photoconductor cartridge 50. These force receiving portions 31 e and 31 f are both pressed by a pressing member provided on the apparatus main body side, and have a function of positioning the photosensitive member cartridge 50 with respect to the drawer member 63. Details will be described later.

<Details of drawer member (support member)>
A drawer member 63 according to Embodiment 2 of the present invention will be described with reference to FIGS. 24 and 25 are perspective views of the drawer unit in the image forming apparatus according to Embodiment 2 of the present invention. 24 and 25 are perspective views seen from different directions.

  The pull-out unit U2 according to this embodiment is different from the first embodiment in that positioning portions 63a and 63b are provided on the pull-out member 63 in order to position the developing cartridge 60 within the pull-out member 63.

  The developer cartridge 60 is positioned in the drawer member 63 by fitting the positioned parts 61 b and 62 b (see FIG. 22) to the positioning parts 63 a and 63 b provided in the drawer member 63.

  As in the case of the first embodiment, the pull-out member 63 is provided with the contact / separation member 42. Since the configuration of the contacting / separating member 42 is the same as that of the first embodiment, the description thereof is omitted. Further, the point that the drawer unit U2 is constituted by the drawer member 63 and the contact / separation member 42 is the same as in the case of the first embodiment.

<Installation of Photosensitive Cartridge and Developer Cartridge to Drawer Member>
The mounting of the developing cartridge 60 (60y, 60m, 60c, 60k) and the photosensitive member cartridge 50 (50y, 50m, 50c, 50k) to the drawer member 63 will be described with reference to FIGS. FIGS. 26 and 27 are perspective views showing how the photosensitive member cartridge and the developing cartridge according to the second embodiment of the present invention are mounted on the drawer member. FIG. 26 and FIG. 27 both show the state of the mounting process of these cartridges, and are views seen from different directions.

  In this embodiment, the photosensitive member cartridge 50 and the developing cartridge 60 are separately attached to the drawer member 63. When both are mounted on the drawer member 63, the developing cartridge 60 is mounted after the photosensitive cartridge 50 is mounted.

  When mounting the photoconductor cartridge 50, the user first mounts the guided portions 31 a and 31 b provided at both ends of the photoconductor cartridge 50 along the guide portions 63 c and 63 d of the drawer member 63. Next, the user mounts the guided portions 31c and 31d along the guide portions 63e and 63f. As a result, the photosensitive member cartridge 50 is mounted in the drawer member 63.

  When mounting the developing cartridge 60, the user holds the developing cartridge 60 so that the positioned portions 61 b and 62 b of the developing cartridge 60 coincide with the positions of the positioning portions 63 a and 63 b provided on the drawer member 63. Installing. However, at the time of mounting, the positioned portions 61b and 62b do not contact the positioning portions 63a and 63b.

  When the photosensitive member cartridge 50 is attached to the drawer member 63, the force receiving portion 31e provided on the photosensitive member cartridge 50 becomes the first convex portion (force applying portion) 42b provided on the contact / separation member 42 (FIG. 26). Contact). Further, the force receiving portion 61a provided on the side cover 71 of the developing cartridge 60 contacts the second convex portion (force applying portion) 42c (see FIG. 26).

  The force receiving portion 31e provided on the photoconductor cartridge 50 abuts on the first convex portion 42b, so that the photoconductor cartridge 50 is held at a position higher than the position where image formation is performed. That is, the surface of the photosensitive drum 1 is held at a position that is one step higher (separated) than the surface recording medium conveyance surface 11a) of the transfer belt 11.

  Further, the surface of the developing roller 40 is separated from the surface of the photosensitive drum 1 by the force receiving portion 61 a provided in the developing cartridge 60 coming into contact with the second convex portion 42 c provided in the contacting / separating member 42. This will be described in particular with reference to FIG. FIG. 28 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 2 of the present invention is mounted in the apparatus main body. FIG. 28 shows a schematic cross-sectional view of the entire apparatus and an enlarged schematic cross-sectional view of the vicinity of one photosensitive drum.

  The 2nd convex part 42c provided in the contacting / separating member 42 is comprised so that it may become one step higher than the 1st convex part 42b. On the other hand, the force receiving portion 31e provided in the photoconductor cartridge 50 and the force receiving portion 61a provided in the developing cartridge 60 are configured to have substantially the same height when receiving no external force. As a result, the developing cartridge 60 is held at a higher position than the photosensitive cartridge 50. Accordingly, the surface of the developing roller 40 is separated from the surface of the photosensitive drum 1.

  Here, the contact / separation member 42 is provided only on one end side of the drawer member 63. A force receiving portion 61 a that receives a force from the second convex portion 42 c of the contact / separation member 42 is also provided only on one side of the developing cartridge 60. However, since the positioned portion 62b provided on the other end side of the developing cartridge 60 is provided outside the longitudinal end of the photosensitive drum 1, the surface of the developing roller 40 is the surface of the photosensitive drum 1. It is possible to leave. That is, the developing cartridge 60 is lifted when the force receiving portion 61a receives the force from the second convex portion 42c on one end side. On the other hand, on the other end side, the positioned portion 62b is kept in contact with the positioning portion 63b of the drawer member 63. Therefore, the developing cartridge 60 is inclined with respect to the photosensitive drum 1. However, as described above, since the positioned portion 62 b is provided outside the longitudinal end of the photosensitive drum 1, the surface of the developing roller 40 is separated from the surface of the photosensitive drum 1.

  As described above, when the photosensitive cartridge 50 and the developing cartridge 60 are mounted, the contact / separation member 42 has the first convex portion 42b in contact with the force receiving portion 31e and the second convex portion 42c in contact with the force receiving portion 61a. In position. At this time, the surface of the photosensitive drum 1 can be positioned at a position separated from the surface of the transfer belt 11. Further, the surface of the developing roller 40 can be positioned at a position separated from the surface of the photosensitive drum 1. In this way, the position when the contact / separation member 42 is at a position where the developing roller 40 and the photosensitive drum 1 can be separated is referred to as a “separation position” as in the first embodiment.

  As described above, in the process of mounting the developing cartridge 60 on the drawer member 63, the developing cartridge 60 is mounted in a state where the surface of the developing roller 40 is separated from the surface of the photosensitive drum 1. Therefore, when the developing cartridge 60 is mounted on the drawer member 63, it is possible to suppress the surface of the photosensitive drum 1 and the surface of the developing roller 40 from rubbing due to the impact at the time of mounting and scratching these surfaces.

  As described above, the surface of the developing roller 40 and the surface of the photosensitive drum 1 and the surface of the photosensitive drum 1 and the surface of the transfer belt 11 are separated from each other, and the photosensitive cartridge 50 and the developing cartridge 60 are pulled out. Mounted on the member 63.

<Mounting the drawer unit in the main unit>
The operation of mounting the drawer unit U2 in the apparatus main body will be described with reference to FIGS. FIG. 29 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 2 of the present invention is mounted in the apparatus main body. FIG. 30 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 2 of the present invention is mounted in the apparatus main body and the door is opened. 29 and 30 show a schematic cross-sectional view of the entire apparatus and an enlarged schematic cross-sectional view of the vicinity of one photosensitive drum. FIG. 31 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 2 of the present invention is mounted in the apparatus main body and the door is closed. FIG. 31 shows a state where the image forming operation is not performed.

  As shown in FIG. 29, the drawer unit U2 (drawer member 63) is mounted in the apparatus main body in the direction of arrow D1. During the mounting operation of the drawer unit U2, the surface of the photosensitive drum 1 and the recording medium transport surface 11a of the transfer belt 11 are kept apart. That is, a gap g is formed between the surface of the photosensitive drum 1 and the recording medium conveyance surface 11 a of the transfer belt 11. Accordingly, the drawer unit U2 can be mounted in the apparatus main body without causing the surface of the photosensitive drum 1 to rub against the surface of the transfer belt 11.

  Further, during the mounting operation of the drawer unit U2, the surfaces of the photosensitive drum 1 and the developing roller 40 are also kept separated from each other. That is, a gap h is formed between the two, and the contact / separation member 42 is positioned at the “separation position”. Therefore, when the drawer unit U2 is mounted in the apparatus main body, it is possible to prevent the surface of the photosensitive drum 1 and the surface of the developing roller 40 from coming into contact with each other due to an impact at the time of mounting or the like.

  As shown in FIG. 30, when the drawer unit U2 is completely inserted into the apparatus main body and the door 10 is opened, the surface of the photosensitive drum 1 and the recording medium conveyance surface 11a of the transfer belt 11 are still separated from each other. doing. Similarly, the surfaces of the photosensitive drum 1 and the developing roller 40 are also spaced apart.

  FIG. 31 shows the door closed. Even when the door 10 is closed, when the image forming operation is not performed, the surface of the photosensitive drum 1, the recording medium conveying surface 11a of the transfer belt 11, the surface of the photosensitive drum 1, and the developing roller. All the surfaces of 40 maintain the separated state. That is, the contact / separation member 42 is located at the “separation position”.

  In the state as described above, it waits until an image forming operation command is received from the apparatus main body.

<Operation of each part during image forming operation>
The operation of each part during the image forming operation will be described with reference to FIGS. FIG. 32 is a perspective view showing a state immediately after an image formation command in the drawer unit according to Embodiment 2 of the present invention. FIG. 33 is a schematic cross-sectional view showing a state in which the drawer unit according to Embodiment 2 of the present invention is mounted in the apparatus main body and the process proceeds to the image forming operation. FIG. 33 shows a schematic sectional view of the entire apparatus and an enlarged schematic sectional view of the vicinity of one photosensitive drum. FIG. 34 is a schematic cross-sectional view showing a state in the middle of shifting to an image forming operation in the image forming apparatus according to Embodiment 2 of the present invention. FIG. 35 is a schematic cross-sectional view showing a state in the middle of shifting to the image forming operation in the image forming apparatus according to Embodiment 2 of the present invention. FIG. 35 shows a schematic sectional view of the entire apparatus and an enlarged schematic sectional view of the vicinity of one photosensitive drum. FIG. 36 is a schematic cross-sectional view showing a state in which an image forming operation is enabled in the image forming apparatus according to Embodiment 2 of the present invention. FIG. 36 shows a schematic cross-sectional view of the entire apparatus and a schematic cross-sectional view in which the vicinity of one photosensitive drum is enlarged.

  When an image formation command is received, a drive gear 46 that is drivingly connected to a motor (not shown) provided in the apparatus main body rotates in the direction of arrow F as shown in FIG. As a result, the contact / separation member 42 moves in the direction of arrow G in the figure by the rack portion 42a meshing with the drive gear 46. When the contact / separation member 42 moves to the position shown in FIG. 32, the force receiving portion 31 e provided on the photoreceptor cartridge 50 is disengaged from the first convex portion 42 b of the contact / separation member 42. However, the force receiving portion 61a provided in the developing cartridge 60 is still located on the second convex portion 42c. The second convex portion 42c is configured to be longer in the moving direction of the contacting / separating member 42 than the first convex portion 42b, thereby enabling such a mechanism.

  FIG. 33 is a schematic cross-sectional view of the entire apparatus in the state shown in FIG. As described above, the surface of the photosensitive drum 1 comes into contact with the surface of the transfer belt 11 by the force receiving portion 31e being detached from the first convex portion 42b by the moving operation of the contact / separation member 52. On the other hand, since the force receiving portion 61a is still receiving the force from the second convex portion 42c, the developing roller 40 is separated from the surface of the photosensitive drum 1. Since the surface of the photosensitive drum 1 and the surface of the developing roller 40 are kept separated from each other, the position of the contact / separation member 42 at this time corresponds to a “separation position”.

  After that, as shown in FIG. 34, the pressing members 65 and 66 provided on the apparatus main body side are driven by a driving source (not shown) and move in the direction of arrow H. These pressing members 65 and 66 abut against force receiving portions 31e and 31f (see FIG. 23) provided on the photosensitive member cartridge 50 to apply force. As a result, the guided portion 31a (see FIG. 23) of the photoconductor cartridge 50 comes into contact with the positioning portion 63c1 (see FIG. 25) provided on the drawer member 63. Further, the guided portion 31b (see FIG. 23) contacts the positioning portion 63d1 (see FIG. 24). Further, the guided portions 31c and 31d (FIG. 23) are fitted into the guide portions 63e and 63f (see FIGS. 24 and 25), and the photosensitive member cartridge 50 is positioned in the drawer member 63.

  As described above, the photosensitive cartridge 50 is positioned in the apparatus main body by the action of the pressing members 65 and 66.

  Thereafter, in order to bring the developing roller 40 and the photosensitive drum 1 into contact with each other, the drive gear 46 further rotates, and the contact / separation member 42 further moves in the arrow G direction (see FIG. 32). As a result, the force receiving portion 61a provided in the developing cartridge 60 is separated from the second convex portion 42c of the contact / separation member 42, and is in a state where no force is received from the second convex portion 42C. As a result, the developing cartridge 60 moves downward in the vertical direction by its own weight, and the surface of the developing roller 40 and the surface of the photosensitive drum 1 come into contact with each other. At this time, the positioned portions 61b and 62b (see FIG. 22) of the developing cartridge 60 and the positioning portions 63a and 63b (see FIGS. 24 and 25) provided on the drawer member 63 are not yet in contact with each other. FIG. 35 is a schematic cross-sectional view showing the state at that time. In this state, as described above, the surface of the developing roller 40 and the surface of the photosensitive drum 1 are in contact with each other. The position when the contact / separation member 42 is in a position where the surface of the developing roller 40 and the surface of the photosensitive drum 1 can be brought into contact with each other is hereinafter referred to as a “contact position”.

  Thereafter, as shown in FIG. 36, the pressing member 67 provided in the apparatus main body is driven by a driving source (not shown) and moves in the direction of arrow J. The pressing members 67 are provided on both side surfaces of the apparatus main body, and a total of four pairs are provided so as to correspond to the developing cartridges 60.

  Then, the pair of pressing members 67 abut against the force receiving portions 61a and 62a (see FIG. 22) provided in the developing cartridge 60, respectively, and apply force. Thus, the positioned portions 61b and 62b (see FIG. 22) of the developing cartridge 60 are pressed toward the positioning portions 63a and 63b (see FIGS. 24 and 25) provided on the drawer member 63. Further, the surface of the developing roller 40 is pressed toward the surface of the photosensitive drum 1 with the positioned portions 61b and 62b as fulcrums. When the surface of the developing roller 40 enters the surface of the photosensitive drum 2 and reaches a predetermined amount, the positioned portions 61b and 62b of the developing cartridge 60 and the positioning portion 63a provided on the drawer member 63 are provided. 63b are in contact with each other.

  As described above, the developing cartridge 60 is positioned in the apparatus main body by the action of the pressing member 67.

  As described above, when the positioning of the developing cartridge 60 is completed, the image forming apparatus 100 is ready to form an image. In this state, the contact / separation member 42 is located at a position where the surface of the developing roller 40 and the surface of the photosensitive drum 1 can be brought into contact, that is, a “contact position”. Note that the image forming operation is as described in the first embodiment.

  When the image formation is completed, the pressing member 67 is moved in a direction opposite to the pressing direction (a direction opposite to the arrow J direction in FIG. 36) by a driving source (not shown). Further, the drive gear 46 is rotated in the direction opposite to the arrow F direction shown in FIG. 32, and the contact / separation member 42 is moved in the arrow I direction in FIG. As a result, the contact / separation member 42 moves to the “separation position” again, and the surface of the developing roller 40 is separated from the surface of the photosensitive drum 1 (see FIG. 34).

  Thereafter, the pressing members 65 and 66 move in the direction opposite to the pressing direction, and the contact / separation member 42 further moves in the direction of arrow I. As a result, the surface of the photosensitive drum 1 is separated from the surface of the transfer belt 11 (the state shown in FIG. 31). In this state, the next image formation command is awaited. Alternatively, when the drawer member 63 is pulled out, the surface of the photosensitive drum 1 and the surface of the transfer belt 11 (recording medium conveying surface 11a), and the surface of the photosensitive drum 1 and the surface of the developing roller 40 remain separated. maintain. That is, the contact / separation member 42 is located at the “separation position”. Therefore, when the drawer member 63 is pulled out of the apparatus main body, it is possible to prevent the surface of the photosensitive drum 1 and the surface of the developing roller 40 from coming into contact with each other due to an impact during movement or the like and being damaged.

<Excellent points of this embodiment>
As described above, the image forming apparatus 100 according to the present embodiment employs a configuration in which the contact / separation member 42 can take the “separation position” and the “contact position”. Then, by the movement of the contact member 42, a configuration is adopted in which the developing roller 40 is moved to a position where it is separated from the photosensitive drum 1 or a position where it abuts on the photosensitive drum 1 as appropriate. As a result, the developing roller 40 and the photosensitive drum 1 can be kept out of contact with each other when image formation is not performed, such as during a drawer operation of the drawer unit U2 (drawer member 63). Therefore, it is possible to suppress the deterioration of each member and extend the life.

Further, the image forming apparatus 100 according to the present embodiment employs a configuration in which the contact / separation member 42 is provided on the drawer member 63. Therefore, as in the case of the conventional example described above, a configuration in which the contact / separation member enters from the apparatus main body side to the inside of the drawer member is required as in the case where a contact / separation member for separating the developing roller from the photosensitive drum is provided on the apparatus main body side. And not. That is, a space for moving the contact / separation member from the apparatus main body side to the position of the cartridge in the drawer member is not required in the apparatus main body, and thus the apparatus main body can be downsized.

  A contact / separation member fixed on the apparatus main body side is provided, and a force receiving portion provided on the cartridge receives a force from the contact / separation member due to a push-in operation or a pull-out operation of the pull-out member, so A configuration in which the contact / separation operation is performed can also be considered.

  However, even when such a configuration is adopted, in order to allow the force receiving portion provided in the cartridge to contact the contact / separation member, it is necessary to project the force receiving portion to the outside of the drawer member. . Therefore, it becomes an obstacle to downsizing of the apparatus. On the other hand, according to the present embodiment, since the contact / separation member 42 is provided in the drawer member 63, it is not necessary to project the force receiving portion 71b more than necessary, and the developing cartridge 63 can be downsized. .

  Even when the above-described configuration is adopted, the cartridge force receiving portion is retracted from the contacting / separating member so that the force receiving portion of the cartridge contacts the contacting / separating member only at a desired timing. The cartridge must be mounted in the state where it is left. Finally, a configuration and mechanism for moving the entire drawing member to a position where the force receiving portion of the cartridge comes into contact with the contact / separation member is required. On the other hand, according to the present embodiment, by providing the contact / separation member 42 in the drawer member 63, the configuration of the apparatus main body can be simplified and the size can be reduced.

  In this embodiment, as an example of the transfer belt 11, the transfer belt 11 transports the sheet material S to the surface of the photosensitive drum 1 and directly transfers the developed image on the photosensitive drum 1 to the sheet material S. Shown when configured. However, the present invention can also be applied to an image forming apparatus that employs an intermediate transfer belt of a type in which a developed image formed on a photosensitive drum is transferred and finally retransferred to a recording medium (sheet material). .

  Further, in this embodiment, the configuration in which the contact / separation member 42 is provided only on one end side of the drawer member 63 is shown. However, a contact / separation member may be similarly provided on the other end side of the drawer member 63. In this case, however, it goes without saying that force receiving portions for receiving force from the contact / separation member also need to be provided on both ends. If contact / separation members are provided on both sides, the photosensitive cartridge and the developing cartridge move without tilting the axes of the photosensitive drum and the developing roller provided in the cartridge. Therefore, the separation state between the photosensitive drum and the transfer belt and the separation state between the photosensitive drum and the developing roller can be further stabilized.

(Example 3)
37 to 42 show a third embodiment of the present invention. In the second embodiment, an example in which a method in which the photosensitive unit (photosensitive cartridge) and the developing unit (developing cartridge) are separately attached to the drawer member is shown. On the other hand, in this embodiment, an example is shown in which the photosensitive unit is fixed to the drawer member and the developing unit (developing cartridge) is mounted on the drawer member. Moreover, in the said Example 1, 2, the example at the time of employ | adopting the structure which a contact / separation member moves to the moving direction of a drawer member was shown. On the other hand, in the present embodiment, an example in which a configuration in which the contacting / separating member moves in a direction perpendicular to the moving direction of the drawer member is shown. Since the basic configuration other than the configuration related to the drawer member and the contact / separation member is the same as that in the above-described embodiment, the description of the same configuration is appropriately omitted. In addition, the same code | symbol is attached | subjected about the component same as the said Example, and the description is abbreviate | omitted suitably.

<Mounting part of drawer unit (drawer member (support member))>
In particular, with reference to FIG. 37, the configuration of the mounting portion of the drawer unit (drawer member) in the apparatus main body will be described. FIG. 37 is a perspective view showing the drawer unit mounting portion in the main assembly of the image forming apparatus according to Embodiment 3 of the present invention. In FIG. 37, the scanner unit and the like are omitted from the members (parts) constituting the apparatus main body so that the configuration of the mounting portion can be easily understood. Also, (a) and (b) in FIG. 37 show perspective views viewed from different directions.

  A pair of guide members 14RX and 14LX for guiding a moving direction of a drawer unit U3, which will be described later, are provided on the inner wall surface of the apparatus main body frame so as to face each other. These guide members 14RX and 14LX are rail-shaped members having a U-shaped cross section for guiding guided portions 13a, 13b, 13c and 13d (see FIG. 38) of a later-described drawer member 63X. Further, these guide members 14RX and 14LX are provided from the vicinity of the entrance of the apparatus body (near the door 10) to the back side so that the drawer member 63X can be guided from the position where the drawer member 63X is pulled out to the position inside the apparatus body. It is provided so as to extend in a substantially horizontal direction.

  Also, above the guide members 14RX, 14LX, pressing members 65X, 66X are provided for pressing and positioning a developing cartridge 60X, which is a developing unit, which will be described later, to a predetermined position. The pressing members 65X and 66X are configured to press the developing cartridge 60X by moving downward by a driving force from the apparatus main body, and position the developing cartridge 60X at a predetermined position in the apparatus main body. Is provided to do.

  Further, below the guide member 14LX, four developing coupling members 26 for transmitting driving to the developing cartridge 60X are provided. These four developing coupling members 26 are arranged in the horizontal direction at substantially equal intervals so as to correspond to the developing cartridges 60X arranged at four places. The developing coupling member 26 transmits a driving force from a driving source (not shown) to the developing cartridge 60X. When the door 10 is opened, the developing coupling member 26 is retracted into the side wall as shown in FIG. 37 (b), and moves to the developing cartridge 60X side in conjunction with the operation of closing the door 10. It is configured to enter.

<Drawer unit>
In particular, with reference to FIGS. 38 and 39, the drawer unit U3 according to the third embodiment of the present invention will be described in detail. FIG. 38 is a perspective view of the drawer unit in the image forming apparatus according to Embodiment 3 of the present invention. FIG. 39 is a schematic cross-sectional view of the drawer unit in the image forming apparatus according to Embodiment 3 of the present invention. In the drawer unit U3 according to the present embodiment, four units having the same basic structure are arranged in the drawer direction. Therefore, in FIGS. 38 and 39, only one of the four basic structures is provided with a reference numeral for easy understanding of the drawings.

  In this embodiment, the photosensitive drum 1 is supported, and the developing cartridge 60X is detachably supported, and moved between an inner position located inside the apparatus main body and an outer position located outside the apparatus main body. A drawer member 63X as a possible support member is provided. The photosensitive drum 1, the charging unit 2, the cleaning unit 6, the waste toner container 30, and the like are fixed to the drawer member 63X. Further, the contact / separation unit 80 is provided on the drawer member 63X. Thus, the drawer unit U3 according to this embodiment includes the drawer member 63X, the photosensitive drum 1, the charging unit 2, the cleaning unit 6, the waste toner container 30, and the like, and the contact / separation unit 80.

Guided portions 13a, 13b, 13c, and 13d that are guided by the guide members 14RX and 14LX of the apparatus main body are provided at the four corners of the drawer member 63X. The guided portions 13a and 13c are guided by the guide member 14RX, and the guided portions 13b and 13d are guided by the guide member 14LX. The guided portions 13a and 13b are configured to protrude outward on the side surface side, and are configured to extend in the pull-out direction so that the pull-out unit U3 does not tilt at the pull-out position. The guided portions 13c and 13d are formed in a columnar shape, and are configured to protrude outward on the side surface side.

  Further, an opening 13l into which the developing coupling member 26 enters is provided on one side wall of the drawer member 63X. The developing coupling member 26 is configured to enter the opening portion 13 l in conjunction with the operation of closing the door 10. The developing coupling member 26 that has entered from the opening portion 131 is engaged with a coupling member 45X (see FIG. 40 described later) of the developing cartridge 60X. Thus, a driving force is transmitted from a driving source (not shown) on the apparatus main body side to the developing cartridge 60X via the developing coupling member 26 on the apparatus main body side and the coupling member 45X on the developing cartridge 60X side.

  Next, a configuration relating to positioning of the developing cartridge 60X with respect to the drawer member 63X will be described.

  The developing cartridge 60X is mounted on the drawer member 63X at a position facing each photosensitive drum 1. Guide portions 13q and 13r for guiding the developing cartridge 60X into the drawing member 63X are provided on both ends of the region where the developing cartridge 60X is mounted. Each guide part 13q, 13r is constituted by a vertically long groove. The groove bottom portion of the vertically long groove constituting the guide portion 13q functions as a positioning portion for positioning the developing cartridge 60X. The opening 13m is provided near the lower end of the front guide 13q in FIG. 38 among the guides 13q provided on both ends.

  An approach / separation unit 80 is provided inside the guide portion 13r. The contact / separation unit 80 includes an contact / separation member 81 that supports the developing cartridge 60X, and a spring 82 that is an urging member that urges the contact / separation member 81 upward. The contact / separation member 81 is configured to have a contact position for bringing the developing roller 40X and the photosensitive drum 1 described later into contact with each other and a separation position for separating the developing roller 40X and the photosensitive drum 1 from each other. Has been.

  The contact / separation units 80 according to the present embodiment are provided at both ends of the mounting area of the developing cartridge 60X.

<Mounting of developing cartridge to drawer member>
The mounting of the developing cartridge 60X (60Xy, 60Xm, 60Xc, 60Xk) to the drawer member 63X will be described with particular reference to FIG. Note that “developing cartridges 60Xy, 60Xm, 60Xc, and 60Xk” are appropriately referred to as “developing cartridge 60X” in the description of the present embodiment, with the suffixes indicating the colors appropriately omitted. Here, y represents yellow, m represents magenta, c represents cyan, and k represents black developer.

  FIG. 40 is a perspective view showing a state when the developing cartridge is attached to the drawer member in the image forming apparatus according to Embodiment 3 of the present invention. When the developing cartridge is mounted, the drawer member 63X is pulled out from the apparatus main body, but the apparatus main body is omitted in FIG.

  The developing cartridge 60X is mounted on each mounting portion provided on the drawer member 63X. The user mounts the developing cartridge 60X in the direction of arrow C, which is substantially the direction of gravity.

  Protrusions 61X are provided on both side surfaces of the developing cartridge 60X. These protrusions 61X are guided by guide portions 13r provided on the drawer member 63X. The outer periphery of the coupling member 45X provided on one side surface of the developing cartridge 60X is covered with a cylindrical rib. The cylindrical rib functions as a guided portion that is guided by a guide portion 13q provided in the drawer member 63X. A guided portion (not shown) is also provided on the other side surface of the developing cartridge 60X. The guided portion is guided by a guide portion 13q provided on the drawer member 63X.

  When mounting the developing cartridge 60X, first, the above-described guided portions respectively provided on both side surfaces thereof are mounted so as to fit into the pair of guide portions 13q provided on the drawer member 63X. Next, the projections 61X provided on both side surfaces of the developing cartridge 60X are mounted so as to fit into the pair of guide portions 13r provided on the drawer member 63X.

  In this way, the developing cartridge 60X is guided by the guide portions 13q and 13r and mounted in the drawer member 63X.

  Here, the developing cartridge 60 </ b> X is attached to the drawer member 63 </ b> X in a state where the protrusions 61 </ b> X provided on both side surfaces thereof are placed on the contact / separation member 81. As described above, the contact / separation member 81 is biased upward by the spring 82, and the developing cartridge 60X is not completely attached only by its own weight. That is, the developing cartridge 60 </ b> X is positioned above a completely mounted position (position where image formation is possible), and the developing roller 40 </ b> X is separated from the photosensitive drum 1. At this time, the pair of guided portions provided in the developing cartridge 60X are not in contact with the positioning portion (groove bottom portion of the groove) in the guide portion 13q for positioning the developing cartridge 60X.

  As described above, the developing roller 40X does not come into contact with the photosensitive drum 1 only by mounting the developing cartridge 60X on the drawer member 63X. Accordingly, it is possible to maintain a state where the surface of the developing roller 40X and the surface of the photosensitive drum 1 are separated from each other during the mounting operation of the developing cartridge 60X. Therefore, it is possible to prevent the surface of the photosensitive drum 1 from being damaged by the mounting operation of the developing cartridge 60X. The position when the contact / separation member 81 is at a position where the developing roller 40X and the photosensitive drum 1 can be separated is referred to as a “separation position” as in the case of the above embodiments.

<Development cartridge positioning configuration>
A positioning configuration of the developing cartridge 60X in the apparatus main body will be described with reference to FIGS. 41 and 42 in particular. FIG. 41 is a schematic cross-sectional view illustrating a state in which the developing cartridge is mounted in the image forming apparatus according to Embodiment 3 of the present invention and the image forming operation is not performed. FIG. 42 is a schematic cross-sectional view illustrating a state where the positioning of the developing cartridge in the image forming apparatus according to Embodiment 3 of the present invention is completed (a state where image formation is possible). 41 and 42, only members related to the positioning of the developing cartridge are shown among various members on the apparatus main body side.

  When an image formation command is received, the developing cartridge 60X moves from a position where the developing roller 40X is separated from the photosensitive drum 1 (see FIG. 41) to a position where it contacts the photosensitive drum 1 (see FIG. 42). As a result, an image can be formed. Hereinafter, this operation will be described.

As described above, the pair of pressing members 65X and 66X is provided in the apparatus main body. These pressing members 65X and 66X are driven by a drive source (not shown) in accordance with an image formation command (image formation signal) and move downward. The pressing members 65X and 66X press the protrusions 61X provided on both side surfaces of the developing cartridge 60X downward. With this pressing force, the pair of protrusions 61 </ b> X pushes the contact / separation member 81 downward against the urging force of the spring 82. As a result, the pair of guided portions provided in the developing cartridge 60X move downward along the guide portion 13q and come into contact with the positioning portion (groove bottom portion of the groove) and stop.

  As described above, the developing cartridge 60X is positioned. In this state, the developing roller 40X comes into contact with the photosensitive drum 1 and is ready for image formation (see FIG. 42). In this way, the position when the contact / separation member 81 is at a position where the surface of the developing roller 40X and the surface of the photosensitive drum 1 can be brought into contact is referred to as a “contact position”.

  As described above, also in this embodiment, as in each of the above embodiments, the contact / separation member 81 is positioned at the “contact position” only when image formation is performed, and “when image formation is not performed”. Located in the “separated position”. Thus, when image formation is not performed, such as during a drawer operation of the drawer unit U3 (drawer member 63X), the developing roller 40X and the photosensitive drum 1 can be in a non-contact state. Therefore, it is possible to suppress the deterioration of each member and extend the life.

  Also in this embodiment, a configuration in which the contact / separation member 81 is provided on the drawer member 63X is employed. Therefore, as in the case of the above embodiments, the apparatus can be reduced in size.

DESCRIPTION OF SYMBOLS 1 Photosensitive drum 4 Developing unit 8 Photosensitive unit 9 Spring 13 Pull-out member 40 Developing roller 41 Toner container 42 Contacting / leaving member 42a Rack part 46 Drive gear 50 Photosensitive cartridge 60, 60X Developing cartridge 61a, 62a Force receiving part 63, 63X Drawer member 65, 66, 65X, 66X Press member 71b Force receiving portion 80 Contact / separation unit 81 Contact / separation member 82 Spring 100 Image forming apparatus P, Py, Pm, Pc, Pk Process cartridge

Claims (8)

An electrophotographic photosensitive member, a developing roller for contacting the electrophotographic photosensitive member to develop an electrostatic latent image formed on the electrophotographic photosensitive member, and a developer for supplying the developing roller are accommodated. A process cartridge having a developer container;
The device body;
A support member that removably supports the process cartridge and is movable between an inner position located inside the apparatus main body and an outer position located outside the apparatus main body;
In an electrophotographic image forming apparatus having
A contact / separation member capable of taking a contact position for contacting the developing roller and the electrophotographic photosensitive member and a separation position for separating the developing roller and the electrophotographic photosensitive member is provided on the support member. An electrophotographic image forming apparatus comprising the electrophotographic image forming apparatus.   The electrophotographic image forming apparatus according to claim 1, wherein the contact / separation member has a driving force receiving portion that receives a driving force for moving between the contact position and the separation position.   The electrophotographic image forming apparatus according to claim 1, wherein the contact / separation member is positioned at the separation position when the support member is positioned at the outer position. The process cartridge includes an urging member that urges the developing roller toward the electrophotographic photosensitive member in order to bring the developing roller and the electrophotographic photosensitive member into contact with each other.
When the support member is located at the inner position, the contact / separation member moves from the separation position to the contact position, whereby the biasing member biases the developing roller, and the developing roller and the 4. The electrophotographic image forming apparatus according to claim 1, wherein the electrophotographic photosensitive member is brought into contact with the electrophotographic photosensitive member. A developing roller for developing an electrostatic latent image formed on the electrophotographic photosensitive member in contact with the electrophotographic photosensitive member; and a developer accommodating portion for accommodating a developer to be supplied to the developing roller. A developing cartridge having
The device body;
The electrophotographic photosensitive member is supported, the developer cartridge is detachably supported, and is movable between an inner position located inside the apparatus main body and an outer position located outside the apparatus main body. A support member;
In an electrophotographic image forming apparatus having
A contact / separation member capable of taking a contact position for contacting the developing roller and the electrophotographic photosensitive member and a separation position for separating the developing roller and the electrophotographic photosensitive member is provided on the support member. An electrophotographic image forming apparatus comprising the electrophotographic image forming apparatus.   The electrophotographic image forming apparatus according to claim 5, wherein the contact / separation member includes a driving force receiving portion that receives a driving force for moving between the contact position and the separation position.   7. The electrophotographic image forming apparatus according to claim 5, wherein the contact / separation member is located at the separation position when the support member is located at the outer position. The apparatus main body includes a pressing member that presses the developing cartridge to bring the developing roller and the electrophotographic photosensitive member into contact with each other.
When the support member is positioned at the inner position, the pressing member presses the developing cartridge, so that the contact / separation member moves from the separation position to the contact position, so that the developing roller and the electrophotography The electrophotographic image forming apparatus according to claim 5, wherein the electrophotographic image forming apparatus is in contact with a photoconductor.