Image forming apparatus

Abstract

To improve workability in replacing a developing device and a photoreceptor unit in an image forming apparatus body.SOLUTION: A developing pressure mechanism moves the position of a developing sleeve to a first position and a second position where the developing sleeve is separated from a photoconductor drum compared to the first position. A pressure lever 233 is to operate the developing pressure mechanism. An operator can grasp a first grip part 301 and a second grip part 302 in pulling out a photoreceptor unit 20 and a developing device 10 in a first direction, respectively. The pressure lever 233 is located on the downstream side of the first grip part 301 and the second grip part 302 with respect to the first direction. The pressure lever 233 is arranged so that, when the developing sleeve is located at the first position, the first grip part 301 and the second grip part 302 are located within a projection surface on which the pressure lever 233 is projected on an upstream side in the first direction, and when the developing sleeve is located at the second position, the first grip part 301 and the second grip part 302 are outside the projection surface.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus such as a copier, a printer, a facsimile, or a multifunction machine having a plurality of these functions. [Background technology]

[0002] In an image forming apparatus, in order to facilitate maintenance and replacement, an image carrier unit having an image carrier such as a photosensitive drum, and a developing device having a developer carrier for developing an electrostatic latent image on the image carrier are configured to be detachable from the image forming apparatus main body. The image carrier unit and the developing device are configured to separate the developer carrier from the image carrier so that the image carrier and the developer carrier do not come into contact with each other when they are attached to or detached from the image forming apparatus main body.

[0003] For example, Patent Document 1 discloses a configuration in which, by operating an operating lever, the position of the developer carrier is moved between a first position where the developer carrier develops an electrostatic latent image on the image carrier, and a second position where the developer carrier is further away from the image carrier than the first position. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2012-58627 A Summary of the Invention [Problem to be solved by the invention]

[0005] Here, a configuration in which the image carrier unit and the developing device are replaced by the user is considered in order to reduce service costs. In the case of the configuration described in Patent Document 1, the user can access the configuration (e.g., the gripping portion) for inserting and removing the developing device and the image carrier unit regardless of whether the developer carrier is in the first position or the second position. In the case of a configuration in which the user can access the configuration for inserting and removing the developing device and the like regardless of whether the developer carrier is in the first position or the second position, a user who is unfamiliar with replacement work may try to pull out the developing device or the image carrier unit before moving the developer carrier to the second position when replacing the developing device or the image carrier unit, which reduces the ease of replacement of the developing device or the image carrier unit.

[0006] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide a configuration that can improve the ease of replacing a developing device or an image carrier unit in the main body of an image forming apparatus. [Means for solving the problem]

[0007] One aspect of the present invention includes an image forming apparatus main body, an image carrier unit that can be pulled out from the image forming apparatus main body in a first direction and inserted in a second direction opposite to the first direction, and has an image carrier capable of carrying an electrostatic latent image on a surface thereof, a developing device that can be pulled out from the image forming apparatus main body in the first direction and inserted in the second direction, and has a developer carrier for developing the electrostatic latent image carried on the image carrier with a developer, a moving mechanism that moves a position of the developer carrier between a first position where the electrostatic latent image carried on the image carrier can be developed by the developer carrier and a second position where the developer carrier is spaced apart from the image carrier more than the first position, and the moving mechanism includes: the image forming apparatus is provided with an operating lever for operating a mechanism thereof, a first grip portion that can be gripped when the image carrier unit is pulled out from the image forming apparatus main body in the first direction, and a second grip portion that can be gripped when the developing device is pulled out from the image forming apparatus main body in the first direction, wherein the operating lever is located downstream of the first grip portion and the second grip portion in the first direction, the first grip portion and the second grip portion are located within a projection plane obtained by projecting the operating lever upstream in the first direction when the developer carrier is located at the first position, and the first grip portion and the second grip portion are positioned outside the projection plane when the developer carrier is located at the second position.

[0008] One aspect of the present invention includes an image forming apparatus main body, an image carrier unit that can be pulled out from the image forming apparatus main body in a first direction and inserted in a second direction opposite to the first direction, the image carrier unit having an image carrier capable of carrying an electrostatic latent image on a surface thereof, a developing device that can be pulled out from the image forming apparatus main body in the first direction and inserted in the second direction, the developing device having a developer carrier for developing the electrostatic latent image carried on the image carrier with a developer, a moving mechanism that moves a position of the developer carrier between a first position where the electrostatic latent image carried on the image carrier can be developed by the developer carrier and a second position where the developer carrier is spaced apart from the image carrier more than the first position, and a manipulation device for operating the moving mechanism. an operating lever, an interlocking member that moves in conjunction with the operation of the operating lever, a first gripping portion that can be gripped when the image carrier unit is pulled out in the first direction from the image forming device main body, and a second gripping portion that can be gripped when the developing device is pulled out in the first direction from the image forming device main body, wherein the interlocking member is located downstream of the first gripping portion and the second gripping portion in the first direction, the first gripping portion and the second gripping portion are located within a projection plane obtained by projecting the interlocking member upstream in the first direction when the developer carrier is located at the first position, and the first gripping portion and the second gripping portion are arranged out of the projection plane when the developer carrier is located at the second position. Effect of the Invention

[0009] According to the present invention, the workability of replacing the developing device and the image carrier unit in the main body of the image forming apparatus can be improved. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic cross-sectional view of an image forming apparatus according to a first embodiment. [Diagram 2] FIG. 2 is a perspective view of a developing device according to the first embodiment. [Diagram 3] FIG. 2 is a cross-sectional view of a developing device according to the first embodiment. [Figure 4]FIG. 2 is a perspective view of a photoconductor unit according to the first embodiment. [Diagram 5] FIG. 2 is a cross-sectional view of a photoconductor unit according to the first embodiment. [Figure 6] FIG. 2 is a perspective view showing a pressure application configuration of the developing device according to the first embodiment. [Figure 7] FIG. 2A is a cross-sectional view showing a pressure-released state of the developing device according to the first embodiment, and FIG. 2B is a cross-sectional view showing a pressure-applied state of the developing device according to the first embodiment. [Figure 8] FIG. 2 is a perspective view of a state in which a developing device and a photoconductor unit according to the first embodiment are mounted in an image forming apparatus main body. [Figure 9] (a) A diagram of the developing device and the photosensitive unit viewed from the front side in a pressurized state of the developing device in the first embodiment, and (b) A diagram of the developing device and the photosensitive unit viewed from the front side in a depressurized state of the developing device in the first embodiment. [Figure 10] FIG. 11 is a perspective view showing a state in which a developing device and a photoconductor unit according to a second embodiment are mounted in an image forming apparatus main body. [Figure 11] (a) A diagram of the developing device and the photosensitive unit viewed from the front side in a pressurized state of the developing device according to the second embodiment, and (b) A diagram of the developing device and the photosensitive unit viewed from the front side in a depressurized state of the developing device according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] <First embodiment> The first embodiment will be described with reference to Figures 1 to 9(b) First, the schematic configuration of an image forming apparatus according to the present embodiment will be described with reference to Figure 1.

[0012] [Image forming equipment] The image forming apparatus 100 of this embodiment is an electrophotographic tandem-type full-color printer equipped with four image forming units PY, PM, PC, and PK, each of which has a photosensitive drum 201 as an image carrier. The image forming apparatus 100 forms a toner image on a recording material in response to an image signal from a document reading device 102 connected to the image forming apparatus main body 101 or a host device such as a personal computer connected to the image forming apparatus main body 101 so as to be able to communicate with the image forming apparatus main body 101. Examples of the recording material include sheet materials such as paper, plastic film, and cloth. The image forming units PY, PM, PC, and PK form yellow, magenta, cyan, and black toner images, respectively.

[0013] The four image forming units PY, PM, PC, and PK included in the image forming apparatus 100 have substantially the same configuration, except for the different developing colors. Therefore, the image forming unit PY will be described as a representative, and descriptions of the other image forming units will be omitted.

[0014] The image forming unit PY is provided with a cylindrical photosensitive member, i.e., a photosensitive drum 201, as an image carrier capable of carrying an electrostatic latent image on its surface. The photosensitive drum 201 is rotated by a driving force transmitted from a driving unit (not shown) provided in the image forming apparatus main body 101. In the image forming unit PY, a charging roller 204 as a charging unit, a developing device 10, a primary transfer roller 31 as a transfer member, and a cleaning blade 206 as a cleaning member are arranged around the photosensitive drum 201. An exposure device (a laser scanner in this embodiment) 22 as an exposure unit is arranged below the photosensitive drum 201 in the figure.

[0015] Toner is supplied to the developing device 10 from a toner bottle 21 serving as a toner storage container through a toner transport path (not shown). In addition, in the image forming section PY, a cleaning roller 205 serving as a charge cleaning member for cleaning the charging member is arranged in contact with the charging roller 204 (see FIG. 5). In this embodiment, the charging roller 204 is brought into contact with the surface of the photosensitive drum 201 with a predetermined pressing force by a biasing member such as a spring, and rotates in accordance with the rotation of the photosensitive drum 201. In addition, the cleaning roller 205 is brought into contact with the surface of the charging roller 204 with a predetermined pressing force by a biasing member such as a spring, and rotates in accordance with the rotation of the charging roller 204.

[0016] An intermediate transfer device 300 is disposed above each image forming unit in FIG. 1. The intermediate transfer device 300 is configured such that an endless intermediate transfer belt 30 serving as an intermediate transfer body is stretched around a plurality of rollers and moves (rotates). A primary transfer roller 31 is disposed at a position facing each photosensitive drum 201 on the inner peripheral surface side (back surface side) of the intermediate transfer belt 30. The primary transfer roller 31 is pressed against the photosensitive drum 201 via the intermediate transfer belt 30, forming a primary transfer portion where the intermediate transfer belt 30 and the photosensitive drum 201 are in contact with each other. The primary transfer roller 31 rotates in accordance with the rotation of the intermediate transfer belt 30.

[0017] Further, a secondary transfer roller 32, which is a roller-shaped secondary transfer member, is disposed at a position facing the secondary transfer opposing roller 33 on the outer circumferential surface side (front surface side) of the intermediate transfer belt 30. The secondary transfer roller 32 is pressed against the secondary transfer opposing roller 33 via the intermediate transfer belt 30, forming a secondary transfer section where the intermediate transfer belt 30 and the secondary transfer roller 32 are in contact with each other. Further, a belt cleaning device 35, which serves as an intermediate transfer body cleaning section, is disposed at a position facing the tension roller 34 on the outer circumferential surface side of the intermediate transfer belt 30. The intermediate transfer belt 30 is formed endlessly from a dielectric resin such as polyimide.

[0018] A fixing device 60 that fixes the toner image to the recording material P is disposed downstream of the secondary transfer portion in the recording material transport direction. The fixing device 60 has, for example, a fixing roller as a fixing rotator heated by a heat source such as a heater, and a pressure roller as a pressure rotator that forms a fixing nip portion between the fixing roller and the fixing roller. The toner image on the recording material transported to the fixing nip portion is heated and pressurized, thereby fixing the toner image to the recording material.

[0019] A cassette 40 containing recording material P is disposed at the bottom of the image forming apparatus 100. The recording material P fed from the cassette 40 is conveyed by conveying rollers 41 toward the registration rollers 50. Then, the leading edge of the recording material P hits the registration rollers 50, which are in a stopped state, and a loop is formed, thereby correcting the skew of the recording material P. Thereafter, the registration rollers 50 start to rotate in synchronization with the toner image on the intermediate transfer belt 30, and the recording material P is conveyed to the secondary transfer section.

[0020] A process of forming, for example, a four-color full-color image by the image forming apparatus 100 configured as described above will be described. First, when an image forming operation starts, the surface of the rotating photosensitive drum 201 is uniformly charged to a predetermined potential of a predetermined polarity by the charging roller 204. In this embodiment, a voltage is applied to the charging roller 204 from a high-voltage power source (not shown), causing discharge on the surface of the photosensitive drum 201, thereby charging the surface of the photosensitive drum 201.

[0021] Next, the photosensitive drum 201 is scanned and exposed by a laser beam corresponding to an image signal generated by the exposure device 22. As a result, an electrostatic latent image corresponding to the image signal is formed on the photosensitive drum 201. The electrostatic latent image on the photosensitive drum 201 (on the image carrier) is visualized by toner contained in the developing device 10 as a developer, and becomes a visible image. In this embodiment, the normal charging polarity of the toner is negative. The developing device 10 has a developing sleeve 12 as a developer carrier that carries the toner and transports it to a portion (developing position) facing the photosensitive drum 201. The developing sleeve 12 is driven to rotate. During development, a predetermined developing voltage is applied to the developing sleeve 12 from a high-voltage power source as a developing power source (not shown).

[0022] The toner image formed on the photosensitive drum 201 is primarily transferred to the intermediate transfer belt 30 at a primary transfer section formed between the photosensitive drum 201 and a primary transfer roller 31 arranged with the intermediate transfer belt 30 sandwiched therebetween. At this time, a primary transfer bias, which is a voltage of the opposite polarity (positive polarity in this embodiment) to the charge polarity of the toner during development, is applied to the primary transfer roller 31 from a high-voltage power source (not shown). Toner remaining on the surface of the photosensitive drum 1 after the primary transfer (transfer residual toner) is removed by a cleaning blade 206, collected in a collected toner transport path, and discharged outside the photosensitive unit 20 by a toner transport screw 207 (see FIG. 5).

[0023] Such an operation is performed in sequence in each image forming section for yellow, magenta, cyan, and black, and the four color toner images are superimposed on the intermediate transfer belt 30. After that, the recording material P stored in the cassette 40 is conveyed to the secondary transfer section in accordance with the timing of the formation of the toner images. Then, in the secondary transfer section, the four color toner images on the intermediate transfer belt 30 are secondarily transferred all at once onto the recording material P by the action of the secondary transfer opposing roller 33. When the recording material P passes through the secondary transfer section, a secondary transfer voltage, which is a voltage of the opposite polarity to the charge polarity of the toner at the time of development, is applied to the secondary transfer roller 32 from a high-voltage power source (not shown). Toner that was not transferred in the secondary transfer section and remains on the intermediate transfer belt 30 is removed by a belt cleaning device 35.

[0024] Next, the recording material P is conveyed to the fixing device 6, where it is heated and pressurized as it passes through the fixing nip. The toner on the recording material P is then melted and mixed, and fixed as a full-color image onto the recording material P. Thereafter, the recording material P is discharged onto the discharge tray 80 by the discharge rollers 70. This completes a series of image forming processes.

[0025] In addition, the image forming apparatus 100 of this embodiment is also capable of forming a monochrome or multi-color image, such as a monochrome black image, by using image forming units for a desired monochrome color or for some of the four colors.

[0026] [Developing device] Next, the configuration of the developing device 10 will be described with reference to Figures 2 and 3. The developing device 10 is a developing device that uses a two-component developer containing non-magnetic toner and magnetic carrier. The developing device 10 of this embodiment is configured to be detachable from the image forming device main body 101 by sliding it from the image forming device main body 101 along the longitudinal direction (the direction of the rotation axis of the developing sleeve 12), and can be replaced for maintenance or the like.

[0027] In this embodiment, the developing device 10 and the photoconductor unit 20, which will be described later, can be inserted and pulled out along the longitudinal direction with respect to the image forming apparatus main body 101. That is, the developing device 10 and the photoconductor unit 20 can be pulled out in a first direction with respect to the image forming apparatus main body 101, and can be inserted in a second direction opposite to the first direction. The pulling direction (first direction) of the developing device 10 and the photoconductor unit 20 is a direction from the back side to the front side of the image forming apparatus 100 (from the back side to the front back side of the paper surface of FIG. 1), and the inserting direction (second direction) is the opposite direction. The front side of the image forming apparatus 100 is the side where an operator operates the image forming apparatus 100, and is, for example, the side where an operation unit for operating the image forming apparatus 100, such as an operation panel, is arranged. Hereinafter, when the terms "front side" and "rear side" are simply used, they refer to the front side and the rear side of the image forming apparatus 100.

[0028] The developing device 10 includes a developing container 11 that contains a developer, a developing sleeve 12 as a developer carrier, and the like. The developing sleeve 12 is held rotatably relative to the developing container 11 about a rotation axis α, and is configured to develop an electrostatic latent image formed on the photosensitive drum 201 at a developing position where the photosensitive drum 201 and the developing sleeve 12 face each other. Driving force is transmitted to the developing sleeve 12 from the rear side of the image forming apparatus main body 101 via a sleeve gear 17.

[0029] In addition, in the developing device 10, there are disposed a developing blade 112 for regulating the toner coat amount on the surface of the developing sleeve 12 to a constant amount, and screw members 113 and 114 for stirring and conveying the toner in the toner storage section 111 in the developing container 11. In the developing device 10, the developer in the toner storage section 111 is stirred and conveyed by the screw members 113 and 114 to be carried on the surface of the developing sleeve 12, and the layer thickness (coat amount) of the developer carried on the developing sleeve 12 is regulated by the developing blade 112. Then, the developer whose layer thickness has been regulated is conveyed to a development position by the rotation of the developing sleeve 12, and is used to develop an electrostatic latent image on the photosensitive drum 201. The developer remaining on the developing sleeve 12 after development is collected in the toner storage section 111, and is stirred and conveyed again by the screw members 113 and 114.

[0030] After being inserted into the image forming apparatus main body 101, the developing device 10 is positioned relative to the photosensitive unit 20 by being pressed by a developing pressure mechanism 23 (described later) provided in the image forming apparatus main body 101, and the developing sleeve 12 and the photosensitive drum 201 are arranged close to each other with a predetermined gap between them.

[0031] [Photoconductor unit] Next, the configuration of the photoconductor unit 20 will be described with reference to Figures 4 and 5. The photoconductor unit 20 of this embodiment is configured such that a photoconductor drum 201 as a photoconductor, a charging roller 204 as a charging member, a cleaning roller 205 as a charging cleaning member, and a cleaning blade 206 as a cleaning member are integrally held by a drum frame 202 as a frame. The photoconductor unit 20 is detachable from the image forming apparatus main body 101 by sliding it from the image forming apparatus main body 101 along the longitudinal direction (the direction of the rotation axis of the photoconductor drum 201), and can be replaced for maintenance or the like.

[0032] A photosensitive drum 201 is supported on the drum frame 202 so as to be rotatable about a rotation axis via a bearing (not shown). The photosensitive drum 201 is provided with a coupling 203 for receiving a driving force from a motor (not shown) provided in the image forming apparatus main body 101 as a driving source and rotating the photosensitive drum 201 when the photosensitive drum 201 is attached to the image forming apparatus main body 101.

[0033] The charging roller 204 is rotatably supported by a charging roller bearing (not shown), and is pressed against the photosensitive drum 201 by a pressure spring (not shown). The cleaning roller 205 is rotatably supported by a cleaning roller bearing (not shown), and is pressed against the charging roller 204 by a pressure spring (not shown). In addition, a cleaning blade 206 is fixed to the drum frame 202 as a cleaning member for cleaning the surface of the photosensitive drum 201, and is provided so as to come into contact with the surface of the photosensitive drum 201 in a counter direction to the rotation direction of the photosensitive drum 201 during image formation.

[0034] A toner transport path is provided near the cleaning blade 206 to collect and transport the transfer residual toner removed from the surface of the photosensitive drum 201 by the cleaning blade 206. The toner transport path is provided with a toner transport screw 207 as a transport member for transporting the collected toner to the outside of the photosensitive unit 20. The toner transported to the outside of the photosensitive unit 20 by the toner transport screw 207 is collected in a collected toner container (not shown) provided in the image forming apparatus main body 101.

[0035] [Gripping part] The above-mentioned photoconductor unit 20 includes a first gripping portion 301 that can be gripped when the photoconductor unit 20 is pulled out from the image forming apparatus main body 101. The above-mentioned developing device 10 includes a second gripping portion 302 that can be gripped when the developing device 10 is pulled out from the image forming apparatus main body 101. As shown in FIG. 4, the first gripping portion 301 is provided on the front end (downstream end in the first direction) of the drum frame 202 of the photoconductor unit 20 so as to protrude further forward. As shown in FIG. 2, the second gripping portion 302 is provided on the front end (downstream end in the first direction) of the developing container 11 of the developing device 10 so as to protrude further forward. In particular, in this embodiment, the second gripping portion is provided on the developing device main body 14 described later. An operator such as a user grips the first gripping portion 301 and the second gripping portion 302 to insert or remove the photoconductor unit 20 and the developing device 10 into or from the image forming apparatus main body 101.

[0036] The first gripping portion 301 and the second gripping portion 302 may have any shape as long as the shape is easy for the operator to grasp, and may be the same or different. In this embodiment, the first gripping portion 301 and the second gripping portion 302 have approximately the same shape. The first gripping portion 301 and the second gripping portion 302 are each formed in an approximately L-shape when viewed from the front side, and are provided with hooking plate portions 301a and 302a formed approximately perpendicular to the insertion / removal direction so that the front end portions can be easily hooked with fingers. The hooking plate portions 301a and 302a also function as portions to be pushed in by hand when the photoconductor unit 20 and the developing device 10 are inserted into the image forming apparatus main body 101.

[0037] [Development pressure mechanism] As described above, the developing device 10 and the photosensitive unit 20 can be replaced for maintenance or the like, but in the image forming state, the developing sleeve 12 and the photosensitive drum 201 are disposed in close proximity to each other. Therefore, if the developing device 10 is inserted or removed from the image forming apparatus main body 101 in this state, there is a possibility that the developing sleeve 12 or the photosensitive drum 201 may be scratched by friction. Therefore, when installing or removing the developing device 10 or the photosensitive unit 20, it is necessary to first separate the developing sleeve 12 and the photosensitive drum 201 by a sufficient distance so that they do not rub against each other.

[0038] For this reason, the developing device 10 of this embodiment has a fixed part 13 fixed to the image forming device body 101, and a developing device body 14 which is a movable part movable relative to the fixed part 13. The fixed part 13 is located upstream of the developing sleeve 12 in terms of the insertion direction of the developing device 10 into the image forming device body 101. In other words, the fixed part 13 is a part which positions and fixes the front part of the developing device 10 with respect to the image forming device body 101.

[0039] In this embodiment, the fixing part 13 is positioned on the frame 90 (see FIG. 8) on the front side of the image forming apparatus main body 101, and then the fixing part 13 is fixed to the frame 90 by a fastening member such as a screw. As a result, the developing device 10 is fixed to the image forming apparatus main body 101, and is prevented from coming off from the image forming apparatus main body 101. The prevention of the developing device 10 from coming off is not limited to this configuration. For example, after the developing device 10 is mounted on the image forming apparatus main body 101, as described later, when the pressure lever 233 is rotated to position the developing device main body 14 at the pressure position, a part of the pressure lever 233 or a member provided on the pressure shaft 231 may be engaged with the end surface on the front side of the fixing part 13. In any case, it is sufficient that the developing device 10 is fixed so as not to come off on the front side in the insertion direction by fastening or engaging the fixing part 13 with a member on the image forming apparatus main body 101 side after the fixing part 13 is positioned on the frame 90.

[0040] In this embodiment, the direction of movement of the developing device main body 14 relative to the fixed portion 13 is the direction of rotation about an engagement portion 15, which will be described later. The developing device main body 14 has a developing sleeve 12. A developing pressurizing mechanism 23 as a moving mechanism can move the developing device main body 14 between a first position (contact position) where the developing sleeve 12 is close to the photosensitive drum 201 and can develop an electrostatic latent image carried on the photosensitive drum 201 with the developing sleeve 12, and a second position (separated position) where the developing sleeve 12 is farther away from the photosensitive drum 201 than the first position. At the contact position, a part of the developing device main body 14 comes into contact with a part of the photosensitive unit 20, thereby determining the positional relationship between the developing sleeve 12 and the photosensitive drum 201.

[0041] The configuration and operation of such a developing and pressurizing mechanism 23 will be described with reference to Fig. 6 to Fig. 7(b). Fig. 6 and Fig. 7(a) are a perspective view and a cross-sectional view showing a developing and pressurizing release state, i.e., a state in which the developing device 10 is not pressed against the photosensitive unit 20 and the developing sleeve 12 is located at a second position where the developing sleeve 12 is separated from the photosensitive drum 201. Fig. 7(b) is a perspective view and a cross-sectional view showing a developing and pressurizing state, i.e., a state in which the developing device 10 is pressed against the photosensitive unit 20 and the developing device main body 14 is located at a first position where the developing sleeve 12 is close to the photosensitive drum 201.

[0042] The developing and pressurizing mechanism 23 includes a rod-shaped pressurizing shaft 231 arranged in parallel to the longitudinal direction of the developing device 10, and a pressing portion 232 is arranged on the pressurizing shaft 231. In this embodiment, the pressing portions 232 are provided at two positions, one on the front side and one on the back side of the pressurizing shaft 231, and rotate together with the pressurizing shaft 231. A pressurizing lever 233 as an operating lever is engaged with the pressurizing shaft 231 on the front side of the image forming apparatus main body 101, and an operator such as a user can rotate the pressurizing shaft 231 by gripping and operating the pressurizing lever 233. In this embodiment, the pressurizing lever 233 is a plate-shaped member, and has a shape that can cover the first gripping portion 301 and the second gripping portion 302 at the abutting position, as described later. In addition, the pressing portion 232 is biased so as to protrude in a direction away from the pressurizing shaft 231 by a biasing member such as a spring (not shown).

[0043] As shown in Fig. 6, when the developing device 10 is attached to the image forming device main body 101, the developing device main body 14 is connected to the fixed part 13 by the engagement part 15 on the front side, and is connected to the image forming device main body 101 by an engagement part (not shown) provided on the frame 91 (see Fig. 8) on the rear side. The developing device main body 14 is rotatable about a rotation axis β (see Fig. 4) of a rotation shaft 15a of the engagement part 15. The engagement part 15 is composed of a first hole part provided in the fixed part 13, a second hole part provided in the developing device main body 14, and the rotation shaft 15a as a shaft part that engages with the first hole part and the second hole part.

[0044] In this way, the developing device main body 14 of the developing device 10 can rotate around the rotation shaft 15a so as to be movable between an abutment position and a separation position with respect to the photosensitive unit 20. When the developing device main body 14 is simply mounted in the mounting position with respect to the image forming device main body 101, it is in a state in which it is tilted counterclockwise CCW in the figure around the rotation axis of the rotation shaft 15a due to its own weight as shown in FIG. 7(a), and the developing sleeve 12 is separated from the photosensitive drum 201. In other words, the developing device main body 14 is in the separation position. When the developing sleeve 12 and the photosensitive drum 201 are in this state separated from each other, the developing device 10 can be attached to and detached from the image forming device main body 101 without colliding with or coming into contact with each other.

[0045] When the pressure lever 233 is rotated clockwise (CW) with the developing device 10 attached to the image forming apparatus main body 101, as shown in Fig. 7(b), the pressing portion 232 on the pressure shaft 231 comes into contact with the pressure force receiving portion 143 as a contact portion provided on the developing device main body 14. The pressure force receiving portions 143 are formed on the rear and front sides of the developing device main body 14, respectively.

[0046] Then, the developing device main body 14 rotates clockwise CW around the rotation axis of the rotation shaft 15a, and the developing sleeve 12 moves to an abutment position (first position) close to the photosensitive drum 201. At this time, the pressing portion 232 is biased by a biasing member (not shown), so that the developing device main body 14 is biased in the clockwise CW direction.

[0047] Furthermore, when the developing device main body 14 is in contact with the photosensitive unit 20, by rotating the pressure lever 233 counterclockwise CCW, the pressing portion 232 on the pressure shaft 231 is released from contact with the pressure force receiving portion 143, as shown in Fig. 7(a). Then, the developing device main body 14 tilts counterclockwise CCW, the contact between the developing sleeve 12 and the photosensitive drum 201 is released, and the developing sleeve 12 moves to the separated position (second position).

[0048] [Relationship between grip and operating lever] Next, the relationship between the first gripping portion 301 of the photoconductor unit 20, the second gripping portion 302 of the developing device 10, and the pressure lever 233 will be described with reference to FIG. 8 to FIG. 9(b). FIG. 8 is a schematic diagram showing the developing device 10, the photoconductor unit 20, and the front frame 90 and the rear frame 91 of the image forming device main body 101. The developing device 10 and the photoconductor unit 20 are attached to the image forming device main body 101 by moving them in the direction of the arrow X (second direction) shown in FIG. 8, and are removed from the image forming device main body 101 by moving them in the direction of the arrow Y (first direction). As described above, the second gripping portion (developing device gripping portion) 302 and the first gripping portion (photoconductor unit gripping portion) 301 are provided on the developing device 10 and the photoconductor unit 20, respectively, to improve the ease of insertion and removal.

[0049] As shown in Fig. 8, the pressure lever 233 is located downstream (front side) of the first gripping portion 301 and the second gripping portion 302 in the first direction (Y direction). Figs. 9(a) and (b) are diagrams showing the positional relationship between the first gripping portion 301, the second gripping portion 302, and the pressure lever 233 in the contact position (first position) and the separation position (second position) of the developing device 10 and the photoconductor unit 20. Figs. 9(a) and (b) are diagrams showing a state in which the developing device 10 and the photoconductor unit 20 are attached to the image forming apparatus main body 101, and the image forming apparatus main body 101 is viewed from the front side.

[0050] 9A, the pressure lever 233 is disposed such that the first grip portion 301 and the second grip portion 302 are located within a projection plane of the pressure lever 233 projected upstream in the first direction (toward the rear side) when the developing sleeve 12 is located at the abutment position. That is, the position of the pressure lever 233 in a state in which the developing device main body 14 is located at the abutment position is a position that covers the first grip portion 301 and the second grip portion 302 when the image forming device main body 101 is viewed from the front side. Therefore, even if an operator such as a user opens a front door or the like of the image forming device main body 101 to look inside the image forming device main body 101, the first grip portion 301 and the second grip portion 302 are not visible or are difficult to see by the operator.

[0051] 9B, the pressure lever 233 is disposed so that the first grip portion 301 and the second grip portion 302 are out of the projection plane of the pressure lever 233 projected upstream in the first direction (toward the rear side) when the developing sleeve 12 is located at the separated position. That is, the position of the pressure lever 233 in a state where the developing device main body 14 is located at the separated position is a position where the first grip portion 301 and the second grip portion 302 are exposed when the image forming device main body 101 is viewed from the front side. Therefore, when an operator such as a user opens a front door or the like of the image forming device main body 101 and looks inside the image forming device main body 101, the operator can visually confirm the first grip portion 301 and the second grip portion 302.

[0052] In this manner, in the present embodiment, when the developing device main body 14 is in the abutting position, the pressure lever 233 covers the first grip portion 301 and the second grip portion 302, thereby preventing the operator from accidentally pulling out the developing device 10 or the photoconductor unit 20. When the developing device main body 14 is in the separated position, the pressure lever 233 retreats from the position covering the first grip portion 301 and the second grip portion 302 to expose the first grip portion 301 and the second grip portion 302. This allows the operator to operate the pressure lever 233 to pull out the developing device 10 or the photoconductor unit 20 in a state in which the developing sleeve 12 is separated from the photoconductor drum 201, improving the ease of replacement of the developing device 10 or the photoconductor unit 20 with respect to the image forming device main body 101.

[0053] <Second embodiment> The second embodiment will be described with reference to Figures 10 to 11(b). In the first embodiment described above, the pressure lever 233 itself covers the first gripping portion 301 and the second gripping portion 302 at the abutment position. In contrast, in this embodiment, the first gripping portion 301 and the second gripping portion 302 are covered by the shielding member 234 that moves in conjunction with the operation of the pressure lever 233 at the abutment position. Since the other configurations and functions are the same as those of the first embodiment described above, the same reference numerals are used for the similar configurations, and explanations and illustrations are omitted or simplified, and the following description will focus on the points that are different from the first embodiment.

[0054] 10, a shielding member 234 is disposed on the pressure shaft 231 as an interlocking member, and is rotatable in conjunction with the operation of the pressure lever 233. The shielding member 234 is, for example, a plate-shaped member, and has a shape capable of covering the first gripping portion 301 and the second gripping portion 302 at the abutting position. The shielding member 234 is fixed to the pressure shaft 231 with a phase shift in the rotational direction from the pressure lever 233.

[0055] Furthermore, the shielding member 234 is located downstream (front side) of the first gripping portion 301 and the second gripping portion 302 in the first direction (Y direction), and is located upstream (rear side) of the pressure lever 233. That is, in a state in which the developing device 10 and the photoconductor unit 20 are attached to the image forming apparatus main body 101, the shielding member 234 is located between the pressure lever 233 and the first gripping portion 301 and the second gripping portion 302 in the first direction.

[0056] 11A, when the developing sleeve 12 is located at the abutment position (first position), the first grip portion 301 and the second grip portion 302 of the shielding member 234 are located within a projection plane of the shielding member 234 projected upstream in the first direction. That is, when the developing device main body 14 is located at the abutment position, the position of the shielding member 234 is a position that covers the first grip portion 301 and the second grip portion 302 when the image forming device main body 101 is viewed from the front side. Therefore, even if an operator such as a user opens a front door of the image forming device main body 101 to look inside the image forming device main body 101, the first grip portion 301 and the second grip portion 302 are not visible or are difficult to see by the operator.

[0057] 11B, the shielding member 234 is disposed so that the first gripping portion 301 and the second gripping portion 302 are out of the projection plane of the shielding member 234 projected toward the upstream side (rear side) in the first direction when the developing sleeve 12 is located at the separated position (second position). That is, the position of the shielding member 234 in a state where the developing device main body 14 is located at the separated position is a position where the first gripping portion 301 and the second gripping portion 302 are exposed when the image forming device main body 101 is viewed from the front side. Therefore, when an operator such as a user opens a front door of the image forming device main body 101 and looks inside the image forming device main body 101, the operator can recognize the first gripping portion 301 and the second gripping portion 302.

[0058] In this embodiment, as shown in Figures 11(a) and (b), the pressure applying lever 233 is in a position where it does not cover the first gripping portion 301 and the second gripping portion 302, regardless of whether the developing sleeve 12 is in the abutment position or the separation position.

[0059] In this embodiment, when the developing device main body 14 is in the abutting position, the shielding member 234 covers the first gripping portion 301 and the second gripping portion 302, thereby preventing the operator from accidentally pulling out the developing device 10 or the photoconductor unit 20. When the developing device main body 14 is in the separated position, the shielding member 234 retreats from the position covering the first gripping portion 301 and the second gripping portion 302 to expose the first gripping portion 301 and the second gripping portion 302. This allows the operator to operate the pressure lever 233 to pull out the developing device 10 or the photoconductor unit 20 in a state in which the developing sleeve 12 is separated from the photoconductor drum 201, improving the ease of replacement of the developing device 10 or the photoconductor unit 20 with respect to the image forming device main body 101.

[0060] This embodiment is effective in the case where the first gripping portion 301 and the second gripping portion 302 cannot be covered by the pressure lever 233 at the contact position as in the first embodiment due to, for example, interference with other members. However, the first embodiment has the advantage that it is not necessary to separately provide the shielding member 234 as in the second embodiment.

[0061] <Other embodiments> In the first and second embodiments described above, the pressure lever 233 and the shielding member 234 are plate-shaped and cover the first grip portion 301 and the second grip portion 302 at the abutment position. However, in the first embodiment, a through hole or a notch may be formed in a part of the pressure lever 233. In this case, even if the pressure lever 233 covers the first grip portion 301 and the second grip portion 302 at the abutment position, there is a possibility that a part of the first grip portion 301 or the second grip portion 302 can be seen through the through hole or the notch. Even in this state, it is effective if the operator has difficulty in accessing the first grip portion 301 and the second grip portion 302. In other words, if the first grip portion 301 and the second grip portion 302 are located within a projection plane obtained by projecting the pressure lever 233 upstream in the first direction at the abutment position, a part of the first grip portion 301 and the second grip portion 302 may be exposed. Similarly, in the second embodiment, a through hole or a notch may be formed in a part of the shielding member 234 . [Explanation of symbols]

[0062] 10. Developing device 12 Developing sleeve (developer carrier) 13... Fixed part 14. Developing device body 20...Photosensitive unit (image carrier unit) 23...Development pressure mechanism (movement mechanism) 100 Image forming apparatus 101... Image forming apparatus main body 201: Photosensitive drum (image carrier) 233 Pressure lever (operating lever) 234... Shielding member (interlocking member) 301...1st gripping part 302...Second gripping part

Claims

1. An image forming apparatus main body, an image carrier unit that can be pulled out in a first direction relative to the image forming apparatus body and can be inserted in a second direction opposite to the first direction, the image carrier unit having an image carrier capable of carrying an electrostatic latent image on a surface thereof; a developing device that is removable from the image forming apparatus main body in the first direction and removable in the second direction, the developing device having a developer carrier for developing an electrostatic latent image carried on the image carrier with a developer; a moving mechanism that moves a position of the developer carrier between a first position where the electrostatic latent image carried on the image carrier can be developed by the developer carrier and a second position where the developer carrier is spaced apart from the image carrier more than the first position; an operating lever for operating the moving mechanism; a first gripping portion that can be gripped when the image carrier unit is pulled out from the image forming apparatus main body in the first direction; a second gripping portion that can be gripped when the developing device is pulled out from the image forming apparatus main body in the first direction, an operating lever is located downstream of the first grip portion and the second grip portion in the first direction, and when the developer carrier is located at the first position, the first grip portion and the second grip portion are located within a projection plane obtained by projecting the operating lever upstream in the first direction, and when the developer carrier is located at the second position, the first grip portion and the second grip portion are positioned outside the projection plane.

2. the developing device includes a fixing portion that is fixed to the image forming apparatus main body when the developing device is attached to the image forming apparatus main body, and a developing device main body that has the developer carrier and is supported movably relative to the fixing portion, 2. The image forming apparatus according to claim 1, wherein the moving mechanism is a mechanism for moving the main body of the developing device relative to the fixed portion.

3. 3. The image forming apparatus according to claim 2, wherein the second gripping portion is provided on a main body of the developing device.

4. An image forming apparatus main body, an image carrier unit that can be pulled out in a first direction relative to the image forming apparatus body and can be inserted in a second direction opposite to the first direction, the image carrier unit having an image carrier capable of carrying an electrostatic latent image on a surface thereof; a developing device that is removable from the image forming apparatus main body in the first direction and removable in the second direction, the developing device having a developer carrier for developing an electrostatic latent image carried on the image carrier with a developer; a moving mechanism that moves a position of the developer carrier between a first position where the electrostatic latent image carried on the image carrier can be developed by the developer carrier and a second position where the developer carrier is spaced apart from the image carrier more than the first position; an operating lever for operating the moving mechanism; A linking member that moves in conjunction with the operation of the operating lever; a first gripping portion that can be gripped when the image carrier unit is pulled out from the image forming apparatus main body in the first direction; a second gripping portion that can be gripped when the developing device is pulled out from the image forming apparatus main body in the first direction, an interlocking member that is located downstream of the first gripping portion and the second gripping portion in the first direction, the first gripping portion and the second gripping portion being located within a projection plane obtained by projecting the interlocking member upstream in the first direction when the developer carrier is located at the first position, and the first gripping portion and the second gripping portion being positioned outside the projection plane when the developer carrier is located at the second position.

5. the developing device includes a fixing portion that is fixed to the image forming apparatus main body when the developing device is attached to the image forming apparatus main body, and a developing device main body that has the developer carrier and is supported movably relative to the fixing portion, 5. The image forming apparatus according to claim 4, wherein the moving mechanism is a mechanism for moving the main body of the developing device relative to the fixed portion.

6. 6. The image forming apparatus according to claim 5, wherein the second gripping portion is provided on the main body of the developing device.

Images