JP3871265B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus having a drawer body supported so as to be able to be pulled out by a main body of the image forming apparatus.
[0002]
[Prior art]
2. Description of the Related Art A device having a drawer body supported so as to be drawable with respect to a device body has been used in various technical fields. For example, an image forming apparatus configured as a copying machine, a printer, a facsimile, or a complex machine of these is an example (see, for example, Patent Document 1). This type of image forming apparatus can easily perform maintenance operations such as replacement of the unit supported by the drawer, maintenance, and inspection by pulling out the drawer. In such an apparatus, if a plurality of units can be individually attached to and detached from the drawer, each unit can be replaced according to the life of each unit. However, when one of the first units is attached to the drawer body and the other second unit is attached to or detached from the drawer body, the element of the second unit becomes the element of the first unit at the time of attachment / detachment. There is a risk of damaging the element when struck by force. In particular, in the case of an image forming apparatus in which the first unit is composed of a photoconductor unit and the second unit is composed of an image forming unit, if the photoconductor is scratched, the image quality of the formed image is deteriorated. Absent.
[0003]
[Patent Document 1]
JP-A-8-36346 (page 6, FIG. 3)
[0004]
[Problems to be solved by the invention]
An object of the present invention is to provide an image forming apparatus having a drawer that eliminates the above-mentioned conventional drawbacks.
[0005]
[Means for Solving the Problems]
To achieve the above object, the present invention provides a photoconductor unit having a photoconductor on which a toner image is formed, an image forming unit having at least one process device for forming a toner image on the photoconductor, and an image. A drawer body supported so as to be drawable with respect to the forming apparatus main body; and a shaft for driving the photoconductor with a base end side supported by the image forming apparatus main body. The image forming unit is assembled to the shaft so as to be removably inserted in the axial direction, and is positioned relative to the shaft. Then, when the drawer body is positioned in the radial direction of the shaft and the drawer body is pulled out or pushed in, the photosensitive unit and the image forming unit move together with the drawer body, and the drawer body is pulled out and supported by the main body of the image forming apparatus. The photosensitive unit and the image forming unit can be separately detached from the drawer in a state where the formed shaft is detached from the photoconductor unit and the image forming unit, and together with the drawer, the photoconductor unit When the image forming unit is pulled out, the photoconductor unit and the image forming unit are configured to move relative to each other in a substantially vertical direction away from each other, and the side from which the drawer, the photoconductor unit, and the image forming unit are pulled out is arranged. When the front side and the opposite side are the back side, and the photoconductor unit and the image forming unit are set at a predetermined loading position in the main body of the image forming apparatus, the end on the back side of the photoconductor unit is When the portion of the shaft to be fitted is a first shaft portion, and the shaft portion on the near side of the first shaft portion is a second shaft portion, the diameter of the second shaft portion is the first shaft portion. Of shaft part The photosensitive unit and the image forming unit are pulled out together with the drawer, and the end on the back side of the photosensitive unit is changed from the first shaft portion to the second shaft portion. When the transition is made, the rear end of the photosensitive unit is moved downward by its own weight, and the rear end of the photosensitive unit moved downward is received by the drawer. When the unit is set at a predetermined loading position in the main body of the image forming apparatus, the image forming unit is fitted to the shaft via a bearing, and together with the drawer, the photosensitive unit and the image forming unit. And an urging means for moving the image forming unit upward relative to the drawer when the fitting between the image forming unit and the shaft is released. Proposed (claim 1).
[0006]
Similarly, in order to achieve the above object, the present invention provides a photoreceptor unit having a photoreceptor on which a toner image is formed, and a charging device, a developing device, a cleaning device, and a charge eliminating device for forming the toner image on the photoreceptor. An image forming unit, a drawer body supported so as to be able to be pulled out with respect to the main body of the image forming apparatus, and a shaft whose base end is supported by the main body of the image forming apparatus. And the image forming unit are detachably assembled to the shaft in the axial direction thereof, and when the drawer is pulled out or pushed in, the photosensitive unit and the image forming unit move together with the drawer, and the drawer The body is pulled out, and the photoconductor unit and the image forming unit are separated separately in a state where the shaft supported by the image forming apparatus main body is detached from the photoconductor unit and the image forming unit. When the photosensitive unit and the image forming unit are pulled out together with the drawer, the photosensitive unit and the image forming unit relatively move in a direction in which they are separated from each other in the vertical direction. The drawer body, the photoreceptor unit, and the image forming unit are drawn out from the front side, and the opposite side is the back side. The photoreceptor unit and the image forming unit are arranged in a predetermined body in the image forming apparatus main body. When set at the loading position, the shaft portion with which the end on the back side of the photoconductor unit is fitted is the first shaft portion, and the shaft portion on the front side of the first shaft portion is the second shaft portion. The diameter of the second shaft portion is set to be smaller than the diameter of the first shaft portion, and together with the drawer, the photosensitive unit and the image forming unit are pulled out to form the photosensitive portion. Of the body unit When the end on the side shifts from the first shaft portion to the second shaft portion, the end on the back side of the photoconductor unit moves downward due to its own weight, and the back of the photoconductor unit that moves below the photoconductor unit. When the image forming unit is set at a predetermined loading position in the image forming apparatus main body, the image forming unit is connected to the shaft via a bearing. When the fitting is started, the photosensitive unit and the image forming unit are started to be pulled out together with the drawer, and when the fitting between the image forming unit and the shaft is released, the image forming unit is moved upward with respect to the drawer. An image forming apparatus characterized in that it is provided with an urging means for moving to a position (Claim 2).
[0007]
3. The image forming apparatus according to claim 1, wherein the drawer has a drawer body and a back holder attached to the drawer body, and is located on the back side of the photosensitive unit moved downward. It is advantageous if the end portion is received by the receiving surface of the back holder.
[0008]
Furthermore, in the image forming apparatus according to claim 3, an end portion on the near side of the photoreceptor unit is prohibited so as to prohibit relative movement in the axial direction between the photoreceptor unit and the shaft and relative rotation between the two. Is pressed toward the back side by the pressure member, and the end on the back side of the photosensitive unit is engaged with the engaging member fixed to the shaft by the pressure of the pressure member, and the drawer is When the photoconductor unit and the image forming unit are pulled out together with the body, a regulating means for regulating an amount of the photoconductor unit pressurized by the pressure member to move to the back side relative to the drawer body It is advantageous to provide (Claim 4).
[0009]
Further, in the image forming apparatus according to any one of claims 1 to 4, when the photoreceptor unit and the image forming unit are pulled out together with the drawer, the front end of the photoreceptor unit is caused by its own weight. It is advantageous that the structure is configured to move downward and that the end on the near side of the photosensitive unit that has moved downward is received by the drawer (claim 5).
[0010]
Further, in the image forming apparatus according to claim 5, the drawer body has a drawer body and a near-side holder attached to the drawer body, and the end portion on the near side of the photosensitive unit moved downward is provided. It is advantageous if it is configured to be received by the front side holder (claim 6).
[0011]
The image forming apparatus according to claim 6, wherein a receiving member for the pressure member is rotatably supported by the near-side holder, and an end portion on the near side of the photosensitive unit moved downward is provided. It is advantageous if it is configured to be received by the front side holder via the receiving member (Claim 7).
[0012]
Furthermore, in the image forming apparatus according to claim 6, the front end portion of the photosensitive unit that has been moved downward is supported by the front holder so that the receiving member for the pressure member is rotatably supported. It is advantageous that the front side holder is configured to be received via the receiving member and the pressure member (Claim 8).
[0013]
In the image forming apparatus according to any one of claims 6 to 8, it is advantageous that the back side holder and the near side holder are detachably attached to the drawer body (claim 9).
[0014]
Furthermore, in the image forming apparatus according to any one of claims 1 to 9, when the image forming unit is set at a predetermined loading position in the image forming apparatus main body, the image forming unit is mounted on the shaft. When the image forming unit is fitted through a bearing, and the photoconductor unit and the image forming unit are started to be pulled out together with the drawer, and the image forming unit and the shaft are disengaged, and the image forming unit moves downward. It is advantageous if the image forming unit is configured to be received by the drawer, and the moving amount of the image forming unit at this time is smaller than the moving amount of the photoconductor unit. (Claim 10).
[0015]
Further, in the image forming apparatus according to any one of claims 1 to 10, it is advantageous to provide a lifting means for raising the drawer when pulling out the photosensitive unit and the image forming unit together with the drawer. (Claim 11).
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below in detail with reference to the drawings.
[0019]
FIG. 1 is a schematic cross-sectional view showing an image forming apparatus which is an example of an apparatus having a drawer. The image forming apparatus shown here has four photoconductors 3 arranged in the image forming apparatus main body 1, and a yellow toner image, a magenta toner image, a cyan toner image, and a black toner image are provided on each photoconductor. Are formed respectively. Here, each photoconductor 3 is formed in a drum shape, but a photoconductor composed of an endless belt can also be used. Further, when it is necessary to identify these photoconductors, the symbols 3Y, 3M, 3C, and 3BK are attached to these photoconductors. If necessary, these photoconductors can be identified as the first, second, third, and fourth photoconductors. When there is no need to identify them, the photoconductor is indicated by reference numeral 3.
[0020]
An intermediate transfer member 4, which is an example of a transfer material, is disposed facing the first to fourth photoconductors 3Y to 3BK, and the intermediate transfer member 4 shown here is wound around a plurality of support rollers 12, 13, and 14. It is configured by an endless belt that is hung and driven to travel in the direction of arrow A.
[0021]
Since the operation and the operation of forming the toner image on each of the first to fourth photoconductors 3Y, 3M, 3C, and 3BK are substantially the same, the toner image is formed on the first photoconductor 3Y. Only the configuration will be described. FIG. 2 is an enlarged view of the photosensitive member 3Y and process devices disposed around the photosensitive member 3Y. The photosensitive member 3Y is driven to rotate counterclockwise in FIGS. At this time, the surface of the photoreceptor is uniformly charged to a predetermined polarity by the charging device 7. The charging device 7 shown here includes a charging roller 15 that is disposed opposite to the photoreceptor 3Y and rotates, and a case 16 that supports the charging roller 15.
[0022]
As described above, the writing surface (in this example, a laser beam) L emitted from the exposure device 8 shown in FIG. 1 is applied to the charged surface of the photoreceptor 3Y charged by the charging device 7. As a result, an electrostatic latent image is formed on the photoreceptor 3Y, and the electrostatic latent image is visualized as a yellow toner image by the developing device 9. The developing device 9 shown here has a developing case 17 and a developing roller 18 that is driven and rotated by the developing case 17, and an electrostatic latent image is generated by a dry developer carried on the developing roller 18. Visualized as a toner image.
[0023]
A first transfer device 10 constituted by a transfer roller is disposed at a position substantially opposite to the first photoconductor 3Y across the intermediate transfer member 4 composed of an endless belt. The yellow toner image on the photoreceptor 3Y is transferred onto the intermediate transfer member 4. The residual transfer toner that is not transferred to the intermediate transfer body 4 and remains on the first photoconductor 3Y is removed by the cleaning device 11. The cleaning device shown here has a cleaning case 19 and a cleaning blade 21 supported by the case, and this blade 21 abuts on the surface of the photoconductor 3Y to remove residual toner on the photoconductor 3Y. . The surface of the photoconductor 3Y that has passed through the cleaning device 11 is irradiated with light from the static eliminator 22 to initialize its surface potential.
[0024]
In exactly the same manner, magenta toner images, cyan toner images, and black toner images are respectively formed on the second to fourth photoreceptors 3M, 3C, and 3BK shown in FIG. 1, and these toner images are converted into yellow toner images. Are transferred in succession on the transferred intermediate transfer body 4. In this way, a four-color superimposed toner image is formed on the intermediate transfer member 4.
[0025]
On the other hand, as shown in FIG. 1, a second transfer device 23 is disposed so as to face the support roller 14 with the intermediate transfer body 4 formed of an endless belt interposed therebetween. A sheet feeding device 5 is disposed below the image forming apparatus main body 1, and a recording material P as a final transfer material made of, for example, transfer paper or a resin film is provided in the direction indicated by an arrow B from the sheet feeding device 5. The recording material P is fed to the transfer area between the second transfer device 23 and the intermediate transfer body 4 and formed on the intermediate transfer body 4 by the action of the second transfer device 23. The toner image is transferred onto the recording material P. The recording material P carrying the toner image transferred in this way is sent to the fixing device 2 and passes through the fixing device 2. At this time, the toner image is fixed on the recording material P by the action of heat and pressure, and a full-color image is formed on the recording material P. The recording material that has passed through the fixing device 2 is discharged onto the paper discharge unit 6 as indicated by an arrow C. Further, the transfer residual toner adhering to the intermediate transfer member after the toner image is transferred is removed by the cleaning device 80.
[0026]
As described above and shown in FIG. 2, process devices such as the charging device 7, the developing device 9, the transfer device 10, the cleaning device 11, and the charge eliminating device 22 are arranged around the first photoconductor 3 </ b> Y. Yes. In exactly the same manner, the above-described process devices are arranged around the second to fourth photoconductors 3M, 3C, and 3BK, and a latent image is formed on each photoconductor 3 by the process devices. Is visualized as a toner image, and the toner image is transferred to a transfer material to form an image. In the example shown in FIGS. 1 and 2, each toner image formed on each photoconductor 3 is transferred to a transfer material composed of an intermediate transfer body 4, and then the toner image on the intermediate transfer body 4 is transferred to a final transfer material. However, the intermediate transfer body 4 is omitted, and the toner image on each photoconductor 3 is directly transferred onto the transfer material made of the recording material. The superposed toner image can be fixed by a fixing device to obtain a full color image.
[0027]
Here, at least one of the above-described process devices arranged around each photoconductor 3 and forming a toner image on the photoconductor is configured as a unitized image forming unit 24. In this example, four image forming units are provided. 24 is provided. The number of image forming units is appropriately set according to the form of the image forming apparatus, and at least one image forming unit is provided.
[0028]
FIG. 3 shows a state in which one image forming unit 24 and a photoconductor unit 41 (to be described later) are removed from a drawer 31 (to be described later). FIG. 4 shows the image forming unit 24 as viewed from the opposite side to FIG. FIG. As is apparent from FIGS. 2 to 4, the image forming unit 24 includes a front wall 25, a rear wall 26, and first and second stays 27 and 28 that integrally connect the front wall 25 and the rear wall 26 (FIG. 2). ), A charging device 7, a developing device 9, a cleaning device 11, and a charge eliminating device 22 for forming a toner image on the photosensitive member 3 are detachable but integrally assembled. An image unit 24 is configured. The unit frame 29, the case 16 of the charging device 7, the developing case 17 of the developing device 9, and the cleaning case 19 of the cleaning device 11 constitute a unit case 30 of the image forming unit 24, as shown in FIG. The lower part of the photoreceptor 3 is exposed from the lower opening 32 of the unit case 30. Further, the writing light L enters the unit case 30 from the light incident port 33 formed in the unit case 30. All of the image forming units 24 are substantially the same except that the color of the developer contained in the developing device is different.
[0029]
FIG. 3 shows a state in which the front door (not shown) of the image forming apparatus main body 1 is opened, a face plate described later is removed, and the drawer body 31 is pulled out from the image forming apparatus main body. As can be seen from FIG. 5 and FIG. 5, the drawer body 31 includes a front frame plate 34, a back frame plate 35, and a plurality of connection plates 36A, 36B, 36C, 36D that integrally connect the frame plates 34, 35. , 36E and a frame-like drawer main body 42, and slide rails 37, 37A are fixed to the connecting plates 36A, 36E, respectively. On the other hand, a pair of guide rails 38 (only one of which is shown in FIG. 3) is also fixed in the image forming apparatus main body 1, and the slide rails 37, 37 A fixed to the drawer 31 are slid onto the guide rails 38. It fits freely. When the front door of the image forming apparatus main body 1 is opened, the face plate is removed, and the drawer body 31 is pulled in the direction indicated by the arrow X, each slide rail 37 slides with respect to each guide rail 38, and the drawer body 31. Is pulled out of the main body of the image forming apparatus as shown in FIG.
[0030]
As shown in FIG. 3, flanges 39 and 40 are fixed to each end portion in the longitudinal direction of the drum-shaped photoconductor 3, and the photoconductor 3 and the flanges 39 and 40 constitute an integral photoconductor unit 41. In addition, the image forming apparatus of this example has four photoconductor units. The photoreceptor unit 41 and the image forming unit 24 are pulled out or pushed into the image forming apparatus main body 1 together with the drawer 31 and set at a predetermined loading position in the image forming apparatus main body. In this way, when the drawer body 31 supported so as to be drawable with respect to the image forming apparatus main body 1 is pulled out as shown in FIG. 3 and the desired image forming unit 24 is lifted upward, the image formation is performed. The unit 24 can be removed from the drawer 31, and then the photosensitive unit 41 can also be removed from the drawer 31. The imaging unit 24 and the photoreceptor unit 41 can be attached to the drawer 31 by the reverse operation. The operation at this time will be described in detail later.
[0031]
The above-described photoconductor unit 41 having the photoconductor 3 on the surface of which a toner image is formed constitutes an example of a first unit and has at least one process device for forming a toner image on the photoconductor. 24 constitutes an example of the second unit. The image forming apparatus main body 1 constitutes an example of an apparatus main body having a drawer. FIG. 6 is a longitudinal sectional view showing a state in which the photosensitive unit 41, the image forming unit 24, and the drawer 31 are set at predetermined loading positions in the image forming apparatus main body 1. The image forming unit 24 is shown in FIG. FIG. 4 is a diagram showing only the unit case 30 by simplifying this. Here, the drawer 31, the photoreceptor unit 41, and the image forming unit 24 are pulled out in the direction indicated by the arrow X in FIG. 6 and pushed in the direction of the arrow Y as described above. , 41 and the side from which the drawer body 31 is pulled out are the front side, and the opposite side is the back side.
[0032]
As shown in FIG. 6, the main body frame of the image forming apparatus main body 1 has a front side plate 44 located on the near side and a back side plate 45 located on the far side, and an opening 46 formed in the front side plate 44 includes: It is closed by the aforementioned face plate 47 detachably fixed to the front side plate 44 by screws not shown. The face plate 47 is correctly positioned with respect to the front plate 44 by fitting holes formed in the face plate with positioning pins 48 fixed to the front plate 44.
[0033]
Further, a base end side (back side) of a round bar-like shaft 50 is supported on the back side plate 45 of the image forming apparatus main body 1 via a bearing 49 so as to be rotatable about its axis. The side (near side) is rotatably supported by the face plate 47 via a bearing 51 press-fitted into the face plate 47. FIG. 5 shows a state in which the drawer body 31 is viewed from the back side. As shown in this figure, the rear frame plate 35 of the drawer body 31 is provided with a plurality of back-side pins 52 so as to project. As shown in FIG. 3, a plurality of front side pins 53 protrude from the front frame plate 34, and the back side pins 52 and the front side pins 53 are formed in positioning holes formed in the back side plate 45 and the face plate 47. Each is detachably fitted. At this time, as shown in FIG. 6, an elastic member 153 made of rubber, for example, fixed to the face plate 47 is pressed against the front frame plate 34 of the drawer 31 and pressurizes the drawer 31 to the back side. 5 and the stepped portion 52A of the back side pin 52 shown in FIG. In this way, the drawer body 31 is prevented from rattling in the front-rear direction, and the drawer body 31 is positioned with respect to the main body frame of the image forming apparatus main body.
[0034]
Furthermore, as shown in FIG. 6, the end on the back side of the photoconductor unit 41, in the illustrated example, the center hole of the flange 39 on the back side (hereinafter referred to as the back flange) is a portion 50 </ b> A on the back side of the shaft 50. The shaft 50 is slidably fitted in the axial direction of the shaft 50 without rattling. Similarly, the front end of the photoreceptor unit 41, in the illustrated example, the front side flange (hereinafter referred to as the front flange) 40 also has a center hole that does not rattle the front side portion of the shaft 50. The shaft 50 is slidably fitted in the axial direction. Further, as shown in FIGS. 5 and 6, the front side holder 54 and the base of the back side holder 55 are fixed to the front frame plate 34 and the back frame plate 35 of the drawer body 31. Thus, the drawer body 31 has the drawer body 42 and the back side holder 54 and the near side holder 55 attached to the drawer body 42, respectively. At this time, a part of the back flange 39 of the photoconductor unit 41 protrudes into the center hole 56 of the back side holder 55, but the drawer body 31, the photoconductor unit 41, and the image forming unit 24 are the image forming apparatus main body 1. The inner flange 39 does not come into contact with the inner holder 55 in a state where it is set at a predetermined loading position.
[0035]
Further, as shown in FIG. 6, a first receiving member 59 for a pressurizing member 58 made of a compression coil spring is rotatably supported in the center hole of the front holder 54 via a bearing 57. . One end side of the pressure member 58 is in pressure contact with the first receiving member 59, and the other end side of the pressure member 58 is in pressure contact with the second receiving member 60, and the second receiving member 60 is The front end portion of the photosensitive unit 41 is in pressure contact with the front flange 40 in the illustrated example. Thereby, the photoconductor unit 41 is pressurized toward the back side. The second receiving member 60 is fitted into the first receiving member 59 so as to be slidable in the axial direction of the shaft 50, and the first receiving member is inserted into the long hole 61 formed in the second receiving member 60. A claw portion 62 formed in 59 is fitted so as to be capable of relative sliding in the axial direction of the shaft 50. Accordingly, the relative rotation of the first and second receiving members 59 and 60 is prohibited, and both the receiving members 59 and 60 are rotatably supported by the front side holder 54. A shaft 50 extends through the receiving members 59, 60 and the pressure member 58, and the shaft 50 passes through the front frame plate 34 and the rear frame plate 35 of the drawer 31. When the drawer 31, the photosensitive unit 41, and the image forming unit 24 are set at predetermined loading positions in the image forming apparatus main body, the shaft 50 is also added to the first and second receiving members 59, 60. There is no contact with the pressure member 58.
[0036]
On the other hand, as shown in FIGS. 6 and 7, an engagement member 63 having a plurality of teeth formed on a tapered peripheral surface is fixed to the proximal end portion of the shaft 50. A large number of teeth (not shown) formed on the inner peripheral surface of the center hole of the flange 39 mesh with the teeth of the engaging member 63. At this time, since the photosensitive unit 41 is pressurized toward the back side by the pressure member 58 as described above, the teeth of the back flange 39 mesh firmly with the teeth of the engaging member 63. As a result, relative movement and relative rotation between the photosensitive unit 41 and the shaft 50 in the axial direction are prohibited, and the photosensitive unit 41 is positioned with respect to the shaft 50. In this state, when a motor (not shown) connected to the inner end of the shaft 50 is operated and the shaft 50 is driven to rotate around the axis, the rotation is photosensitized via the engaging member 63. The information is transmitted to the body unit 41, and the photoreceptor 3 rotates around its central axis, and the above-described image forming operation is executed. As the photoconductor unit 41 rotates, the first and second receiving members 59 and 60 and the pressure member 58 shown in FIG. 6 are integrally rotated with the photoconductor unit 41. Thus, the shaft 50 serves to drive the photosensitive member 3.
[0037]
As shown in FIG. 4, a through hole 64 is formed in the rear wall 26 of the unit case 30. As shown in FIG. 6, the through hole 64 does not rattle the bearing 65 press-fitted into the shaft 50. Moreover, the shaft 50 is slidably fitted in the axial direction. As shown in FIGS. 3 and 6, a bearing 66 is press-fitted into the through-hole formed in the front wall 25 of the unit case 30 of the image forming unit 24, and the bearing 66 does not rattle the shaft 50. Moreover, the shaft 50 is slidably fitted in the axial direction. In this way, the image forming unit 24 is positioned in the radial direction with respect to the shaft 50. Further, as shown in FIG. 3, a reference pin 67 protruding from the front wall 25 of the unit case 30 is detachably fitted into a positioning hole (not shown) formed in the face plate 47, as shown in FIG. Further, another reference pin 68 projecting from the rear wall 26 of the unit case 30 is detachably fitted into a positioning hole formed in the back side plate 45 as shown in FIG. The reference pins 67 and 68 regulate the angular position of the image forming unit 24. Further, as shown in FIG. 5, a pin 69 protrudes from the front frame plate 34 of the drawer body 31, and the pin 69 is detachably fitted in a hole (not shown) formed in the unit case 30. To do. Thereby, the image forming unit 24 is positioned in the axial direction of the shaft 50.
[0038]
Here, a state in which the drawer 31, the photosensitive unit 41, and the image forming unit 24 are assembled as shown in FIG. 6 is referred to as a drawer assembly 71. FIGS. 8A, 8B, and 8C are schematic views showing a state in which the drawer assembly 71 is pulled out from the image forming apparatus main body. In FIG. 8, some members are omitted, each member is shown in a simplified manner, and hatching indicating the cross section is omitted (the same applies to FIGS. 11 and 12).
[0039]
FIG. 8A shows the same state as FIG. 6 in which the drawer assembly 71 is set at a predetermined loading position in the main body of the image forming apparatus. As described above, the front door of the image forming apparatus main body 1 is opened, the face plate 47 shown in FIG. 6 is removed from the front side plate 44, the opening 46 is opened, and the drawer assembly 71 is moved to the front side, that is, in the arrow X direction. As shown in FIGS. 8B and 8C, the drawer assembly 71 moves to the near side and is pulled out. At the time of this drawing, the shaft 50 is still supported by the image forming apparatus main body on the base end side, so that the shaft 50 is gradually extracted from the photosensitive unit 41 and the image forming unit 24, and FIG. When the drawer 31 is completely pulled out as shown in FIG. 4, the shaft 50 is pulled out from the photosensitive unit 41 and the image forming unit 24. As a result, the photoconductor unit 41 and the image forming unit 24 are in a free state not constrained by the shaft 50, so that the image forming unit 24 can be detached from the drawer 31 by lifting the image forming unit 24 upward. it can. Next, the inner flange 39 of the photosensitive unit 41 can be removed from the inner holder 55 by pressing the photosensitive unit 41 toward the front side and compressing and deforming the pressing member 58 shown in FIG. The photosensitive unit 41 can be detached from the drawer 31 by lifting the back side portion of the photosensitive unit 41 upward as shown in FIG. By reverse operation, the photoconductor unit 41 and the image forming unit 24 can be sequentially assembled to the drawer 31. Next, when the drawer assembly 71 is pushed inward as indicated by the arrow Y in FIG. 8C, the shaft 50 is inserted into the photosensitive unit 41 and the image forming unit 24, and the drawer assembly 71 is shown in FIG. As shown, the image forming apparatus main body 1 is set at a predetermined loading position. At this time, the drawer 31, the photoreceptor unit 41, and the image forming unit 24 are each correctly positioned relative to the image forming apparatus main body 1 by the above-described configurations.
[0040]
When the drawer assembly 71 is pushed in the direction of the arrow Y, the through hole 64 on the back side of the image forming unit 24 is fitted into the bearing 65 fixed to the shaft 50, and the front side attached to the image forming unit 24 is on the near side. The bearing 66 is fitted to the shaft 50, and the center holes of the back flange 39 and the front flange 40 of the photosensitive unit 41 are fitted to the shaft 50. At this time, the shaft 50 is arranged so that the fitting can be performed smoothly. It is preferable that the free end portion on the near side is formed in a small diameter as shown in FIG. 6 or in a tapered shape.
[0041]
As described above, the photoconductor unit 41 is assembled to the shaft 50 so as to be detachable in the axial direction, and is positioned with respect to the shaft 50. The image forming unit 24 is also assembled to the shaft 50 so as to be detachable in the axial direction, and is positioned with respect to the shaft 50 in the radial direction of the shaft 50. When the drawer body 31 is pulled out or pushed in while the shaft 50 is supported by the image forming apparatus main body 1, the photosensitive unit 41 and the image forming unit 24 move together with the drawer body 31. In addition, when the drawer body 31 is pulled out and the shaft 50 supported by the image forming apparatus main body 1 is detached from the photoconductor unit 41 and the image forming unit 24, the photoconductor unit 41 and the image forming unit 24 are separately provided. It is comprised so that it can detach | leave from the drawer body 31. FIG. As described above, since the photosensitive unit 41 and the image forming unit 24 can be separately attached and detached, when only one of them becomes a lifetime, only the one unit can be replaced. It is not necessary to replace the other unit that can still be used sufficiently, and it is possible to avoid a problem that places an unnecessary burden on the user.
[0042]
By the way, when the image forming unit 24 and the photosensitive unit 41 are set in the image forming apparatus main body 1, the elements of the image forming unit 24 such as the charging roller 15, the developing roller 18, the cleaning blade 21, and the like are shown in FIG. As shown in FIG. 4, the surface is in contact with or close to the surface of the photoreceptor 3. Therefore, when the drawer body 31 is pulled out as shown in FIG. 8C and then the image forming unit 24 is lifted upward, the elements of the photoreceptor 3 and the image forming unit 24 remain in the state shown in FIG. If so, the elements of the image forming unit 24 may hit the surface of the photoconductor 3 strongly, and the elements of the photoconductor 3 and the image forming unit 24 may be damaged.
[0043]
Therefore, in the image forming apparatus of this example, as shown in FIGS. 8A, 8 </ b> B, and 8 </ b> C, when the photoreceptor unit 41 and the image forming unit 24 are pulled out together with the drawer 31, The body unit 41 and the image forming unit 24 are configured to move relative to each other in directions away from each other. In FIGS. 8A, 8B, and 8C, δ and δ1 indicate the distance between the image forming unit 24 and the photosensitive unit 41, but the drawer assembly 71 is set in the main body of the image forming apparatus. The interval δ1 when the drawer assembly 71 is pulled out is larger than the interval δ when the drawer is pulled out. In this example, as can be seen from FIGS. 8A to 8C, when the photoconductor unit 41 and the image forming unit 24 are pulled out together with the drawer 31, the photoconductor unit 41 and the image forming unit 24 are substantially connected to each other. Relative movement in the direction of separating in the vertical direction. FIG. 10 shows a state in which the image forming unit 24 and the photosensitive member 3 are separated from each other in the vertical direction, and the charging roller 15, the developing roller 18, and the cleaning blade 21 of the image forming unit 24 are greatly separated from the surface of the photosensitive member 3. Yes.
[0044]
As described above, the image forming unit 24 is attached to and detached from the photoconductor unit 41 in a state where the elements of the image forming unit 24 are separated from the photoconductor 3 or the contact force thereof is weakened. It is possible to prevent the surface and the elements of the image forming unit 24 from being damaged.
[0045]
Next, a more specific configuration example for relatively separating the image forming unit 24 and the photoconductor unit 41 when the drawer assembly 71 is pulled out will be described.
[0046]
As shown in FIG. 6, when the photoconductor unit 41 and the image forming unit 24 are set at a predetermined loading position in the image forming apparatus main body 1, the end on the back side of the photoconductor unit 41 is illustrated. In the example, the above-described portion 50A of the shaft 50 into which the back flange 39 of the photoconductor unit 41 is fitted is referred to as a first shaft portion, and the shaft portion on the nearer side than the first shaft portion 50A is the second shaft portion. When referred to as 50B, the diameter of the second shaft portion 50B is set smaller than the diameter of the first shaft portion 50A. The difference in diameter between the two is, for example, about 1 mm.
[0047]
When the photoreceptor unit 41 and the image forming unit 24 are pulled out in the direction of the arrow X together with the drawer 31, the back end of the photoreceptor unit 41, that is, the back flange 39 is second from the first shaft portion 50 </ b> A. At this time, the end on the back side of the photoconductor unit 41 moves downward by its own weight, and the end on the back side of the photoconductor unit 41 moved below is moved by the drawer 31. It is accepted. The rear flange 39 falls downward and is received by the drawer body 31. In the illustrated example, the drawer 31 has the drawer body 42 and the back holder 55 as described above, and the back end of the photoreceptor unit 41 that has moved downward, that is, the back flange 39 is shown in FIG. (B) and (c), it is received by the receiving surface 55A at the lower part of the inner peripheral surface of the back holder 55. When the drawer assembly 71 is pulled out, the front end of the photosensitive unit 41, that is, the front flange 40 thereof, also moves downward under its own weight as schematically shown in FIGS. 8B and 8C. The front flange 40 is received by the drawer body 31, which will be described in detail later.
[0048]
As described above, the photosensitive unit 41 can be moved away from the image forming unit 24 by dropping the photosensitive unit 41 downward.
[0049]
By the way, when the drawer assembly 71 is set at a predetermined loading position in the main body of the image forming apparatus, as described above, the relative movement of the photosensitive unit 41 and the shaft 50 in the axial direction and the relative rotation of both of them. The front end of the photoconductor unit 41, that is, the front flange 40 is pressed toward the back side by the pressurizing member 58, and the photoconductor unit 41 is applied by the pressurizing force of the pressurizing member 58. The rear flange end 39, that is, the rear flange 39 is engaged with an engagement member 63 fixed to the shaft 50. Therefore, when the drawer assembly 71 starts to be pulled out, the pressure contact force between the back flange 39 and the engaging member 63 gradually weakens and they are separated from each other. At this time, the photoconductor unit 41 is directed toward the back side by the pressure member 58. Therefore, the photosensitive unit 41 moves toward the back side relative to the drawer 31, and the portion 39 </ b> A of the back flange 39 shown in FIG. 6 is a portion 55 </ b> B of the back side holder 55. There is a risk that the rear flange 39 will not fall downward. Therefore, in the image forming apparatus of this example, as described above with reference to FIG. 6, the first receiving member 59 that is immovable in the axial direction of the shaft 50 with respect to the drawer 31, and the first The pressure member 58 is accommodated in the second receiving member 60 movable in the axial direction of the shaft 50 with respect to the receiving member 59, and the first receiving member 59 is inserted into the long hole 61 formed in the second receiving member 60. The claw portion 62 is fitted so as to be slidable in the axial direction of the shaft 50, and is configured to regulate the distance that the second receiving member 60 can move in the axial direction of the shaft 50. As a result, the drawer assembly 71 starts to be pulled out toward the front side, and after the back flange 39 is separated from the engaging member 63, the photosensitive unit 41 is pressurized by the pressurizing member 58 and relatively with respect to the drawer 31. The amount of movement to the back side is limited. Thereby, before the part 39A of the back flange 39 shown in FIG. 6 presses against the part 55B of the back side holder 55, the back flange 39 can fall into the receiving surface 55A of the back side holder 55. As described above, the claw portion 62 formed in the first receiving member 59 and the long hole 61 formed in the second receiving member 60, together with the drawer body 31, connect the photoconductor unit 41 and the image forming unit 24. When it is pulled out to the near side, it constitutes an example of a restricting means for restricting the amount of movement of the photoconductor unit 41 pressurized by the pressure member 58 relative to the drawer 31 relative to the back side.
[0050]
By the way, as described briefly above, when the image forming apparatus of this example pulls out the photoconductor unit 41 and the image forming unit 24 together with the drawer 31, the end portion on the near side of the photoconductor unit 41 is disposed. The front flange 40 is also configured to move downward by its own weight and to receive the front end of the photosensitive unit 41 that has moved downward by the drawer 31. The specific configuration will be described below. An example is clarified.
[0051]
The drawer body 31 of this example has the drawer body 42 and the front side holder 54 attached to the drawer body 42 as described above. Therefore, the front end of the photosensitive unit 41 moved downward, that is, the front flange 40 can be received by the front holder 54. At this time, the front flange 40 may be directly received by the front side holder. However, in the image forming apparatus of this example, the front side holder 54 is provided with the receiving members 59 and 60 for the pressure member 58. Is rotatably supported, so that the front flange 40, which is the end portion on the front end side of the photosensitive unit 41 moved downward, is received by the front holder 54 through the receiving members 59 and 60. ing. That is, as shown in FIGS. 8B and 8C, the front flange 40 dropped downward is received by the receiving surface 60 </ b> A at the lower part of the inner peripheral surface of the second receiving member 60. Further, the second receiving member 60 can be omitted, and the pressure member 58 can be directly brought into pressure contact with the front flange 40, but in this case, the front end portion (front side) of the photosensitive unit 41 moved downward is also possible. The flange 40) is received by the front holder 54 via the pressure member receiving member 59 and the pressure member 58, which are rotatably supported by the front holder 54.
[0052]
Further, the back side holder 55 and the near side holder 54 may be fixed to the drawer main body 42 so as not to be detached, but these holders 54 and 55 are attached to the drawer main body 42 by screws or pins not shown, for example. When detachably attached, after the image forming unit 24 is detached from the drawer 31, the photosensitive unit 41 can be detached from the drawer 31 together with the holders 54 and 55. In this way, without touching the photoreceptor unit itself, the holders 44 and 45 can be grasped by hand, and the photoreceptor unit 41 can be attached to and detached from the drawer 31 and the photoreceptor 3 may be soiled. Can be eliminated.
[0053]
By the way, as shown in FIG. 6, in the image forming apparatus of this example, when the photosensitive unit 41 and the image forming unit 24 are set at predetermined loading positions in the image forming apparatus main body 1, The image forming unit 24 is fitted to the shaft 50 via bearings 65 and 66. From this state, when the photoreceptor unit 41 and the image forming unit 24 are started to be pulled out in the direction of the arrow X together with the drawer 31, the above-mentioned fitting between the image forming unit 24 and the shaft 50 is released. That is, the through hole 64 formed in the rear wall 26 of the unit case 30 is disengaged from the bearing 65 press-fitted into the shaft 50, and the bearing 66 press-fitted into the through hole in the front wall 25 of the unit case 30 is disengaged from the shaft 50. Or a transition to a small diameter portion on the near side of the shaft 50. As a result, the image forming unit 24 moves slightly downward. As shown in FIGS. 8B and 8C, the image forming unit 24 receives the unit case 30 on the drawer main body 42 of the drawer body 31. It is done. At this time, the downward movement amount of the image forming unit 24 is configured to be smaller than the downward movement amount of the photoconductor unit 41. As described above, even when the image forming unit 24 is configured to be lowered in accordance with the drawing operation of the drawer assembly 71, the image forming unit 24 and the photoconductor unit 41 are separated from each other in the vertical direction. It can be moved relatively.
[0054]
Alternatively, as shown in FIGS. 11 (a) and 11 (b), an urging force composed of a leaf spring or a compression coil spring is provided between the front wall 25 and the rear wall 26 of the image forming unit 24 and the drawer body 42. Means 73 is provided, the drawer assembly 71 is pulled out in the direction of arrow X, the through hole 64 of the unit case 30 is detached from the bearing 65, and the bearing 66 press-fitted into the unit case 30 is detached from the shaft 50, or the shaft 50 The image forming unit 24 can be raised by the urging means 73 when the small diameter portion is shifted to. In this way, the photoconductor unit 41 and the image forming unit 24 can be relatively moved in a direction in which they are largely separated from each other in the vertical direction, and the elements of the image forming unit 24 can be greatly separated from the photoconductor 3. When the photosensitive unit 41 and the image forming unit 24 are set at a predetermined loading position in the main body of the image forming apparatus, the image forming unit 24 is fitted to the shaft 50 via the bearings 65 and 66, and the drawer 31 At the same time, the photosensitive unit 41 and the image forming unit 24 are started to be pulled out, and when the fitting between the image forming unit 24 and the shaft 50 is released, the image forming unit 24 is moved upward with respect to the drawer 31. By providing the means 73, the photosensitive unit 41 and the image forming unit 24 can be moved relatively greatly in the vertical direction.
[0055]
Further, in each of the above-described configurations, when the drawer assembly 71 is pulled out to the front side, the photosensitive unit 41 is lowered downward, so that the photosensitive member 3 strongly hits the intermediate transfer member 4 shown in FIG. May be attached. Therefore, it is preferable that the drawer body 31 is lifted slightly upward when the drawer assembly 71 is pulled out. For example, as shown in FIGS. 12A and 12B, an example of a lifting unit is provided on the main body of the image forming apparatus where the photosensitive unit 41 does not interfere when the drawer assembly 71 is pulled out or pushed in. When a roller 74 is rotatably supported and the drawer assembly 71 is pulled out as shown in FIG. 12B, the drawer body 31 is placed on the roller 74, and the drawer body 31 is slightly raised. As described above, when the photosensitive body unit 41 and the image forming unit 24 are pulled out together with the drawer body 31, lifting means for raising the drawer body 31 is provided. Thus, when the drawer body 31 is pulled out or pushed in, the photoreceptor unit 41 can be prevented from interfering with the elements located below it, that is, the intermediate transfer body 4 shown in FIG. The problem that the intermediate transfer member 4 is damaged can be prevented.
[0056]
【The invention's effect】
According to the present invention, when the photoconductor unit and the image forming unit are pulled out together with the drawer, the photoconductor unit and the image forming unit move relative to each other in directions away from each other. It is possible to prevent a problem that the elements of the image forming unit are damaged.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view illustrating an example of an image forming apparatus.
FIG. 2 is an enlarged cross-sectional view of an image forming unit and a photoreceptor unit.
FIG. 3 is a perspective view showing a state in which a drawer is pulled out from the main body of the image forming apparatus and one image forming unit and a photosensitive unit are taken out.
FIG. 4 is a perspective view of the image forming unit when viewed obliquely from the back side.
FIG. 5 is a perspective view when the drawer body is viewed obliquely from the back side.
FIG. 6 is a longitudinal sectional view of the photoconductor unit and the image forming unit in a state where the photoconductor unit and the image forming unit are set in the main body of the image forming apparatus.
FIG. 7 is a view showing an engaging member fixed to a shaft.
FIG. 8 is a schematic explanatory view showing an operation when the drawer assembly is pulled out.
FIG. 9 is a perspective view showing a state when the photosensitive unit is removed from the drawer.
FIG. 10 is a cross-sectional view of the image forming unit and the photoconductor unit when the photoconductor unit is moved downward with respect to the image forming unit.
FIG. 11 is an explanatory view showing another operation mode when the drawer assembly is pulled out.
FIG. 12 is an explanatory view showing still another operation mode when the drawer assembly is pulled out.
[Explanation of symbols]
3,3Y, 3M, 3C, 3BK photoconductor
7 Charging device
9 Development device
11 Cleaning device
22 Static eliminator
24 Image creation unit
31 Drawer
42 drawer body
50 axes
50A first shaft portion
50B Second shaft portion
54 Front side holder
55 Back holder
55A bearing surface
58 Pressure member
59, 60 receiving member
63 engaging member

Claims (11)

  A photoconductor unit having a photoconductor on which a toner image is formed, an image forming unit having at least one process device for forming a toner image on the photoconductor, and supported so as to be drawable with respect to the image forming apparatus main body. And a shaft for driving the photoconductor, the base end side of which is supported by the main body of the image forming apparatus, and the photoconductor unit is assembled to the shaft so that it can be inserted and removed in the axial direction. Is positioned relative to the shaft, and the image forming unit is also detachably assembled in the axial direction with respect to the shaft, and is positioned in the radial direction of the shaft with respect to the shaft, When the drawer body is pulled out or pushed in, the photosensitive unit and the image forming unit move together with the drawer body, and the drawer body is pulled out so that the shaft supported by the image forming apparatus main body has the photosensitive unit and The photoconductor unit and the image forming unit are configured to be able to be detached from the drawer separately from the image unit, and when the photoconductor unit and the image forming unit are pulled out together with the drawer, The body unit and the image forming unit are configured to move relative to each other in a substantially vertical direction away from each other, the side from which the drawer, the photoconductor unit, and the image forming unit are pulled out is the front side, and the opposite side is the back side. In addition, when the photoconductor unit and the image forming unit are set at a predetermined loading position in the main body of the image forming apparatus, the portion of the shaft to which the end on the back side of the photoconductor unit is fitted is first. When the shaft portion on the front side of the first shaft portion is the second shaft portion, the diameter of the second shaft portion is set smaller than the diameter of the first shaft portion, The drawer In both cases, the photoconductor unit and the image forming unit are pulled out, and when the end on the back side of the photoconductor unit shifts from the first shaft portion to the second shaft portion, the back of the photoconductor unit. And the image forming unit is configured to receive the end on the back side of the photosensitive unit that has moved downward by its own weight. When set in the loading position, the image forming unit is fitted into the shaft via a bearing, and starts to pull out the photosensitive unit and the image forming unit together with the drawer, and the image forming unit and the shaft And an urging means for moving the image forming unit upward with respect to the drawer when the fitting is disengaged.   A photoconductor unit having a photoconductor on which a toner image is formed, an image forming unit in which a charging device, a developing device, a cleaning device, and a static eliminator for forming a toner image on the photoconductor are integrally assembled; A drawer body supported so as to be able to be pulled out with respect to the main body of the forming apparatus; and a shaft whose base end is supported by the main body of the image forming apparatus, and the photosensitive unit and the image forming unit are When the drawer is pulled out or pushed in, the photosensitive unit and the image forming unit are moved together with the drawer, and the drawer is pulled out and supported by the image forming apparatus main body. The photosensitive unit and the image forming unit are configured to be able to be detached from the drawer separately in a state where the shaft is detached from the photosensitive unit and the image forming unit, and When the photoconductor unit and the image forming unit are pulled out together with the body, the photoconductor unit and the image forming unit are configured to move relative to each other in a direction that is substantially separated in the vertical direction. When the drawing side of the image forming unit is the front side and the opposite side is the back side, and the photosensitive unit and the image forming unit are set at a predetermined loading position in the image forming apparatus main body, the photosensitive unit The second shaft portion when the shaft portion into which the end portion on the back side of the first shaft portion is fitted is a first shaft portion, and the shaft portion on the near side of the first shaft portion is the second shaft portion. Is set to be smaller than the diameter of the first shaft portion, the photoreceptor unit and the image forming unit are pulled out together with the drawer, and the end on the back side of the photoreceptor unit is the first side. From the shaft part to the second shaft part The rear end of the photosensitive unit is moved downward by its own weight when the transition is made, and the rear end of the photosensitive unit moved downward is received by the drawer. When the image unit is set at a predetermined loading position in the main body of the image forming apparatus, the image forming unit is fitted to the shaft via a bearing, and together with the drawer, the photosensitive unit and the image forming unit. And an urging means for moving the image forming unit upward with respect to the drawer when the fitting between the image forming unit and the shaft is released. .   The drawer body has a drawer body and a back side holder attached to the drawer body, and is configured to receive the end of the back side of the photosensitive unit moved downward by the receiving surface of the back side holder. The image forming apparatus according to claim 1.   In order to prohibit relative movement in the axial direction between the photoconductor unit and the shaft and relative rotation of the two, the front end of the photoconductor unit is pressurized toward the back side by a pressure member, and The pressurizing force of the pressurizing member causes the end on the back side of the photoconductor unit to engage with the engaging member fixed to the shaft, and together with the drawer, the photoconductor unit and the image forming unit are connected to the front side. The image forming apparatus according to claim 3, further comprising a restricting unit that restricts an amount of movement of the photoconductor unit pressurized by the pressure member relative to the drawer relative to the back side when being pulled out.   When the photoconductor unit and the image forming unit are pulled out together with the drawer, the front end of the photoconductor unit is moved downward by its own weight, and the front side of the photoconductor unit moved downward is formed. The image forming apparatus according to claim 1, wherein the side end is received by a drawer.   6. The drawer according to claim 5, wherein the drawer has a drawer body and a near-side holder attached to the drawer body, and the near-side end of the photosensitive unit moved downward is received by the near-side holder. The image forming apparatus described.   The receiving member for the pressure member is rotatably supported by the front side holder, and the front side end portion of the photosensitive unit moved downward is received by the front side holder through the receiving member. The image forming apparatus according to claim 6 configured as described above.   The receiving member for the pressure member is rotatably supported by the front side holder, and the front side end portion of the photosensitive unit moved downward is connected to the front side via the receiving member and the pressure member. The image forming apparatus according to claim 6, wherein the image forming apparatus is configured to be received by a holder.   The image forming apparatus according to claim 6, wherein the back side holder and the near side holder are detachably attached to the drawer main body.   When the image forming unit is set at a predetermined loading position in the main body of the image forming apparatus, the image forming unit is fitted to the shaft through a bearing, and together with the drawer body, the image forming unit and the photosensitive unit. When the image forming unit starts to be pulled out and the fitting between the image forming unit and the shaft is disengaged and the image forming unit moves downward, the image forming unit is configured to be received by the drawer. The image forming apparatus according to claim 1, wherein an amount of downward movement of the image forming unit is configured to be smaller than an amount of downward movement of the photosensitive unit.   11. The image forming apparatus according to claim 1, further comprising a lifting unit that raises the drawer when the photosensitive unit and the image forming unit are pulled out together with the drawer.

Images