JP2012177850A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely attach a developing unit to a suitable position.SOLUTION: A right contact surface and a left contact surface 636a are inclined with respect to a right pressing surface and a left pressing surface 636b, so that when drive is not inputted to a coupling part 814b from a main body side drive transmission part, a boss 812 is not moved, but when the drive is inputted to the coupling part 814b, the boss 812 is moved to a position where the boss 812 comes into contact with the right pressing surface and the left pressing surface 636b.

Description

  The present invention relates to an image forming apparatus such as a laser printer.

  Conventionally, as an electrophotographic system, for example, a so-called tandem type color printer in which photosensitive drums corresponding to yellow, magenta, cyan, and black are arranged in parallel is known.

  As such a tandem type color printer, for example, in Patent Document 1, an apparatus main body and a plurality of photosensitive drums are integrally supported, and can be moved to an inner position inside the apparatus main body and an outer position outside the apparatus main body. A tandem type photosensitive unit and a developing cartridge that is provided on each photosensitive drum and holds a developing roller that supplies developer to the photosensitive drum, and is detachably attached to the tandem type photosensitive unit; and a tandem type photosensitive unit. An image forming apparatus having a pressing member that presses the developing cartridge toward the photosensitive drum is disclosed.

  In this image forming apparatus, when the tandem photosensitive unit is at the outer position, the user mounts the developing cartridge at the mounting position of the tandem photosensitive unit and further receives a pressure from the pressing member from the mounting position (appropriate). The developing cartridge is moved to the position), and then the tandem photosensitive unit is moved to the inner position.

  This is because, if the developing cartridge is not mounted at an appropriate position, for example, it becomes difficult for the developing roller to smoothly supply toner to the photosensitive drum, which causes a problem in image quality and the like.

JP 2010-156791 A

  However, even in the above-described image forming apparatus, the tandem type photosensitive unit may be mounted at the inner position in a state where the developing cartridge is not mounted at an appropriate position. For example, when the tandem type photosensitive unit is vigorously mounted on the apparatus main body, the developing cartridge mounted at an appropriate position may be displaced from the appropriate position by the momentum.

  Therefore, the present application has been made in view of the above problems, and in the configuration in which the moving member is mounted on the apparatus main body, the developing unit is surely placed in an appropriate position with the moving member being disposed at the inner position. An object of the present invention is to provide an image forming apparatus that can be mounted.

  In order to achieve this object, the invention according to claim 1 is directed to an apparatus main body, a photosensitive unit including a photosensitive member, a developing unit including a developing roller and a pressed portion, and the developing roller to the photosensitive member. A pressing member that presses the pressed portion of the developing unit so as to be pressed, and is configured to be movable between an inner position located at an inner position of the apparatus main body and an outer position of the apparatus main body. A driving member for transmitting driving to a driving receiving portion of the photosensitive unit or the developing unit when the moving member is located at the inner position, and the developing unit includes The movable member is configured to be swingable between a first posture in which the pressed portion is pressed by the pressing member and a second posture in which the pressing of the pressing member is released. In the first position And a pressing surface that presses the pressed portion and a contact surface that contacts the pressed portion in the second posture, and the contact surface is driven from the driving member to the driving surface with respect to the pressing surface. When the driving force is not input to the receiving portion, the pressed portion does not move, and when the driving force is input from the driving member to the driving receiving portion, the pressed portion contacts the pressing surface. It is characterized in that it is inclined so as to move to a contact position.

  The invention according to claim 2 is the invention according to claim 1, wherein the pressed portion is a first pressed portion provided on one side of the developing unit in the rotation axis direction of the photoconductor, A second pressed portion provided on the other side in the rotation axis direction of the developing unit, and the pressing member is provided on the one side in the rotation axis direction of the moving member, and the first pressed portion. And a second pressing member that is provided on the other side of the pressing member in the rotation axis direction and presses the second pressed portion.

  According to a third aspect of the present invention, in the second aspect of the present invention, the drive receiving portion is provided on one end side in the rotation axis direction of the photosensitive unit or the developing unit, and the first pressing member Has a first spring, and the second pressing member has a second spring having a spring constant larger than that of the first spring.

  According to a fourth aspect of the present invention, in the second or third aspect of the present invention, the drive receiving portion is provided on one side in the rotational axis direction of the photosensitive unit or the developing unit. The second pressing member is configured such that an angle formed between the pressing surface of the second pressing member and the contact surface is larger than an angle formed between the pressing surface of the first pressing member and the contact surface. It is characterized by being formed.

  According to a fifth aspect of the present invention, in the invention according to any one of the second to fourth aspects, the drive receiving portion is provided on one end side in the rotational axis direction of the photosensitive unit or the developing unit. The second pressing member has a pressing force smaller than that of the first pressing member.

  According to a sixth aspect of the present invention, in the invention according to any one of the first to fifth aspects, the developing unit is configured such that the center of oscillation of the developing unit is coaxial with the rotational axis center of the developing roller. The drive receiving portion is arranged at a position close to the rotation shaft of the developing roller.

  The invention according to claim 7 is the invention according to any one of claims 1 to 6, wherein the moving member is configured such that the developing unit moves in the state where the developing unit is in the second posture. It is characterized by being configured to be detachable from the member.

  The invention according to claim 8 is the process cartridge according to any one of claims 1 to 7, wherein the developing unit and the photoconductor unit are integrally formed process cartridges, and The member is characterized in that the process cartridge is detachable from the moving member when the process cartridge is in the second posture.

  The invention according to claim 9 is the invention according to any one of claims 1 to 8, wherein the moving member includes a plurality of photoconductor units and a plurality of photoconductor units corresponding to the plurality of photoconductor units. It has a developing unit and a plurality of pressing members corresponding to the plurality of developing units.

  According to a tenth aspect of the present invention, the apparatus main body, a photosensitive unit including a photosensitive member, a developing unit including a developing roller and a pressed portion, and the developing roller are pressed against the photosensitive member. A moving member configured to move between an inner position positioned at an inner position of the apparatus main body and an outer position of the apparatus main body, and a pressing member that presses the pressed portion of the developing unit. A drive member for transmitting drive to a drive receiving portion of the photosensitive unit or the development unit when the is located at the inner position, the development unit with respect to the moving member, The pressed portion is configured to be swingable between a first posture in which the pressed member is pressed by the pressing member and a second posture in which the pressing of the pressing member is released, and the pressed portion is configured to move in the first posture. Press member A pressed surface that receives the pressure and a contacted surface that contacts the pressing portion in the second posture, and the contacted surface is driven by the drive member from the driving member with respect to the pressed surface. When the driving force is not input to the portion, the pressing member does not move, and when the driving force is input from the driving member to the drive receiving portion, the pressing member is in contact with the pressed surface. It is characterized by being inclined so as to move to.

  The invention according to claim 11 is the invention according to claim 10, wherein the pressed portion is a first pressed portion provided on one side of the developing unit in the rotation axis direction of the photoconductor, A second pressed portion provided on the other side in the rotation axis direction of the developing unit, and the pressing member is provided on the one side in the rotation axis direction of the moving member, and the first pressed portion. And a second pressing member that is provided on the other side of the pressing member in the rotation axis direction and presses the second pressed portion.

  According to a twelfth aspect of the invention, in the invention of the tenth or eleventh aspect, the drive receiving portion is provided on one end side in the rotational axis direction of the photosensitive unit or the developing unit, The first pressing member has a first spring, and the second pressing member has a second spring having a spring constant larger than that of the first spring.

  The invention according to claim 13 is the invention according to claim 11 or 12, wherein the drive receiving portion is provided on one side in the rotational axis direction of the photosensitive unit or the developing unit. In the second pressed portion, an angle formed between the pressed surface of the second pressed portion and the pressed surface is such that the pressed surface of the first pressed portion and the pressed surface are It is characterized by being formed so as to have an angle larger than the angle formed by.

  According to a fourteenth aspect of the present invention, in the invention according to any one of the eleventh to thirteenth aspects, the drive receiving portion is provided on one end side in the rotational axis direction of the photoconductor unit or the developing unit. The second pressing member is characterized in that the pressing force is smaller than that of the first pressing member.

  The invention according to claim 15 is the invention according to any one of claims 10 to 14, wherein the developing unit is configured such that the swing center of the developing unit is coaxial with the rotational axis center of the developing roller. The drive receiving portion is arranged at a position close to the rotation shaft of the developing roller.

  The invention according to claim 16 is the invention according to any one of claims 10 to 15, wherein the moving member is configured such that the developing unit moves in the state where the developing unit is in the second posture. It is characterized by being configured to be detachable from the member.

  The invention according to claim 17 is the process cartridge according to any one of claims 11 to 16, wherein the developing unit and the photoconductor unit are integrally formed process cartridges, and The member is characterized in that the process cartridge is detachable from the moving member when the process cartridge is in the second posture.

  According to an eighteenth aspect of the present invention, in the invention according to any one of the eleventh to thirteenth aspects, the moving member includes a plurality of photoreceptor units and a plurality of photoreceptor units corresponding to the plurality of photoreceptor units. It has a developing unit and a plurality of pressing members corresponding to the plurality of developing units.

(Consistency between claims and effects)
According to the first aspect of the present invention, the contact surface of the pressing member is located at a position where the pressed portion comes into contact with the pressing surface when a driving force is input from the driving member to the driving receiving portion with respect to the pressing surface. Inclined to move.

  With such a configuration, when a driving force is input from the driving member to the driving receiving portion in a state where the moving member is disposed at the inner position, the developing unit moves to the first posture. As a result, the developing unit can be reliably mounted at an appropriate position.

  The developing unit is automatically mounted at an appropriate position when driving is input to the drive receiving portion. Therefore, it is not necessary for the user to mount the developing unit at an appropriate position, and it is easy to use.

  According to the invention described in claim 2, the pressed part has a first pressed part and a second pressed part, and the pressed part has a first pressed part and a second pressed part. ing.

  With such a configuration, the developing roller can uniformly press the entire area of the photoconductor in the rotation axis direction, so that it is possible to suppress printing defects and the like.

  According to the invention described in claim 3, the drive receiving portion is provided on one side in the rotation axis direction of the developing unit, and the second pressing portion has a spring constant larger than that of the first spring of the first pressing portion. A second spring is provided.

  With such a configuration, the second pressed portion provided on the side opposite to the side on which the drive receiving portion is provided is easily moved to a position where it comes into contact with the pressing surface of the second pressing portion.

  According to the fourth aspect of the present invention, the drive receiving portion is provided on one side in the rotation axis direction of the developing unit, and the second pressing portion is formed by the pressing surface of the second pressing portion and the contact surface. The angle is formed to be larger than the angle formed between the pressing surface of the first pressing portion and the contact surface.

  With such a configuration, the second pressed portion provided on the side opposite to the side on which the drive receiving portion is provided is easily moved to a position where it comes into contact with the contact surface of the second pressing portion.

  According to the fifth aspect of the present invention, the drive receiving portion is provided on one side in the rotation axis direction of the developing unit, and the second pressing portion has a small pressing force of the first pressing portion.

  With such a configuration, the second pressed portion provided on the side opposite to the side on which the drive receiving portion is provided is easily moved to a position where it comes into contact with the contact surface of the second pressing portion.

  According to the sixth aspect of the present invention, the developing unit is configured such that the center of oscillation is coaxial with the center of the rotation axis of the developing roller, and the drive receiving portion is located close to the rotation axis of the developing roller. Has been placed.

  With such a configuration, since the distance that the drive receiving portion swings is short, it is possible to prevent the connection between the drive member and the drive receiving portion when the developing unit swings.

  According to the seventh aspect of the present invention, the developing unit is configured to be detachable from the moving member when the developing unit is in the second posture.

  With such a configuration, only the developing unit can be replaced.

  According to the eighth aspect of the present invention, the process cartridge is configured to be detachable from the moving member when the process cartridge is in the second posture.

  With such a configuration, only the process cartridge can be replaced.

  According to the ninth aspect of the present invention, the moving member has a plurality of photoconductor units, a plurality of developing units, and a plurality of pressing members.

  With such a configuration, even in a color image forming apparatus, the developing unit can be reliably mounted at an appropriate position.

  According to the tenth aspect of the present invention, the abutting surface of the abutted portion is different from the pressed surface when the driving member receives a driving force from the driving member to the driving receiving portion. It is inclined so as to move to a contact position.

  With such a configuration, when driving is input from the driving member to the driving receiving portion with the moving member disposed at the inner position, the developing unit moves to the first posture. As a result, the developing unit can be reliably mounted at an appropriate position.

  The developing unit is automatically mounted at an appropriate position when driving is input to the drive receiving portion. Therefore, it is not necessary for the user to mount the developing unit at an appropriate position, and it is easy to use.

  According to the invention described in claim 11, the pressed part has a first pressed part and a second pressed part, and the pressing member has a first pressing member and a second pressing member. ing.

  With such a configuration, the developing roller uniformly presses the entire area of the photoconductor in the rotation axis direction, so that it is possible to suppress printing defects and the like.

  According to the twelfth aspect of the present invention, the drive receiving portion is provided on one side in the rotation axis direction of the developing unit, and the second pressing member has a larger spring constant than the first spring of the first pressing member. A second spring is provided.

  With such a configuration, the second pressing portion provided on the side opposite to the side on which the drive receiving portion is provided can easily move to a position where the second pressing portion contacts the pressed surface of the second pressed portion.

  According to the thirteenth aspect of the present invention, the drive receiving portion is provided on one side in the rotation axis direction of the developing unit, and the second pressed portion is in contact with the pressed surface of the second pressed portion. The angle formed by the surface is formed to be larger than the angle formed by the pressed surface of the first pressed portion and the contacted surface.

  With such a configuration, the second pressing portion provided on the side opposite to the side on which the drive receiving portion is provided can easily move to a position where the second pressing portion contacts the pressed surface of the second pressed portion.

  According to the fourteenth aspect of the present invention, the drive receiving portion is provided on one side of the developing unit in the rotation axis direction, and the second pressing member has a small pressing force of the first pressing member.

  With such a configuration, the second pressing member provided on the side opposite to the side on which the drive receiving portion is provided can easily move to a position where the second pressing member contacts the pressed surface of the second pressed portion.

  According to the fifteenth aspect of the present invention, the developing unit is configured such that the center of oscillation is coaxial with the rotational axis center of the developing roller, and the drive receiving portion is located at a position close to the rotational axis of the developing roller. Has been placed.

  With such a configuration, since the distance that the drive receiving portion swings is short, it is possible to prevent the connection between the drive member and the drive receiving portion when the developing unit swings.

  According to the sixteenth aspect of the present invention, the developing unit is configured to be detachable from the moving member when the developing unit is in the second posture.

  With such a configuration, only the developing unit can be replaced.

  According to the seventeenth aspect of the present invention, the process cartridge is configured to be detachable from the moving member when the process cartridge is in the second posture.

  With such a configuration, only the process cartridge can be replaced.

  According to the invention described in claim 18, the moving member has a plurality of photosensitive units, a plurality of developing units, and a plurality of pressing members.

  With such a configuration, even in the color image forming apparatus, the developing unit can be reliably mounted at an appropriate position.

Side sectional view showing a color laser printer Explanatory drawing explaining the state which pulled out the process unit from the main body casing Plan view of process unit A perspective view of the process unit when viewed from the upper left side (A) Perspective view of developing cartridge in FIG. 1, (b) Perspective view of developing cartridge when gear cover in (a) is removed Explanatory drawing for explaining the guide groove of the right side plate Explanatory drawing for explaining the mounting position of the developing cartridge Explanatory drawing for demonstrating the press position of a developing cartridge Explanatory drawing for demonstrating a left side press lever Explanatory drawing for demonstrating the right side press lever in a modification. Explanatory drawing for demonstrating the process unit of a modification. (A) Process cartridge is in the mounted position, (b) Process cartridge is in the pressed position Explanatory drawing for demonstrating the process unit of a modification. (A) Process cartridge is in the mounted position, (b) Process cartridge is in the pressed position

<1 Overall configuration of color laser printer>
FIG. 1 is a side sectional view showing a schematic configuration of a color laser printer 1 as an example of an image forming apparatus of the present embodiment.

  The color laser printer 1 includes a main body casing 2 as an example of an apparatus main body. In the main body casing 2, a paper feed unit 3 for feeding paper and an image for forming an image on the fed paper are provided. An image forming unit 4 and a paper discharge unit 5 that discharges the paper on which the image is formed are further provided.

  In the following description, unless otherwise specified, the vertical direction shown in FIG. 1 is up and down, the right side in FIG. 1 is front, the left side is rear, the back side of the paper is right, and the front side of the paper is left. Indicates. The direction here is defined based on the direction seen from the person standing in front of the color laser printer 1.

<1-1 Main body casing>
The main casing 2 includes a front cover 21 that opens and closes an opening 23 formed on the front side.

  The front cover 21 is rotatably supported by a cover shaft (not shown) provided at the lower end portion thereof. When the front cover 21 is closed, the opening 23 is closed by the front cover 21. When the front cover 21 is opened, the opening is opened. (See Figure 2)

<1-2 Paper Feed Unit>
The paper feed unit 3 is disposed below the main body casing 2 and includes a paper feed tray 31 for storing paper and a pair of registration rollers 32.

  In the paper feed unit 3 configured as described above, the sheets are separated one by one from the paper feed tray 31 by a roller (not shown) and conveyed toward the image forming unit 4 at a predetermined timing.

<1-3 Image forming unit>
The image forming unit 4 includes a scanner unit 41, a process unit 6 as an example of a moving member, a transfer unit 9, and a fixing unit 10.

<1-3-1 Scanner unit>
The scanner unit 41 is provided in the upper part of the main casing 2 and includes a laser light emitting unit, a polygon mirror, a lens, and a reflecting mirror (not shown).

  In the scanner unit 41 configured as described above, the laser light emitted from the laser light source based on predetermined image data is scanned at high speed in the horizontal direction by the polygon mirror, and passes or reflects through the lens and the reflecting mirror. Irradiates the photosensitive drum.

<1-3-2 Process unit>
The process unit 6 is disposed below the scanner unit 41 and above the paper feed unit 3. The process unit 6 includes a drum unit 60 as an example of a photosensitive unit and a developing cartridge as an example of a developing unit corresponding to each color. 8 and.

  Further, the process unit 6 slides in the front-rear direction between a mounting position (see FIG. 1) where the image forming is possible with respect to the main body casing 2 and a drawing position (see FIG. 2) withdrawn from the main body casing 2. It is provided as possible.

  The drum unit 60 is constructed between four drum subunits 61 corresponding to the developing cartridges 8 of the respective colors, a left side plate 63 and a right side plate 62 that are arranged to face each other with a gap in the left-right direction, and the front ends of the pair of side plates. A front beam 64 and a rear beam 65 provided between the rear ends of the pair of side plates are provided.

  Each drum subunit 61 includes a photosensitive drum 611, a charger 612, and the like as an example of a photosensitive member.

  The four photosensitive drums 611 are provided for the respective colors of black, yellow, magenta, and cyan, and are arranged in parallel at equal intervals in the front-rear direction in the order of black, yellow, magenta, and cyan from the front side.

  In addition, flange members 611a are provided at both ends of each photosensitive drum 611 so as not to be relatively rotatable.

  Further, on the left side surface of the left flange member 611a, there is provided a coupling groove (see FIG. 4) for transmitting drive from a main body side drive transmission portion (not shown) as an example of a drive member.

  The four chargers 612 are provided corresponding to the respective photosensitive drums 611, and are disposed on the rear upper side of the corresponding photosensitive drums 611. The charger 612 is, for example, a scorotron charger having a wire and a grid.

  The four developing cartridges 8 are arranged so as to correspond to the respective photosensitive drums 611, include a developing frame 81, a developing roller 82 that is rotatably supported by the developing frame 81, and a supply roller that supplies toner to the developing roller 82. 83 and a toner storage portion 84 that stores toner. The four developing cartridges 8 are detachably supported with respect to the drum unit 60.

  The developing roller 82 includes a metal roller shaft 821 and a covering portion that covers the roller shaft 821 with a conductive rubber material. The covering portion is a portion that contacts the photosensitive drum 611.

  The supply roller 83 has a metal roller shaft and a covering portion that covers the roller shaft with a conductive foam material.

  For example, non-magnetic one-component polymerized toner is accommodated in the toner accommodating portion 84. The toner container 84 is provided with an agitator 841 for stirring the toner in the toner container 84.

  In the process unit 6 configured as described above, the surface of the photosensitive drum 611 is uniformly charged by the charger 612, the charged surface of the photosensitive drum 611 is exposed by scanning with laser light, and the potential of the exposed portion is detected. Is lowered, an electrostatic latent image is formed on the surface of the photosensitive drum 611.

  On the other hand, the toner in the toner container 84 is supplied onto the developing roller 82 by the supply roller 83 and is frictionally charged between the supply roller 83 and the developing roller 82.

  The toner supplied from the developing cartridge 8 is held on the exposed portion of the photosensitive drum 611, thereby forming a toner image on the surface of the photosensitive drum 611.

<1-3-3 transcription unit>
The transfer unit 9 is disposed above the sheet feeding unit 3 and below the process unit. The transfer unit 9 includes a driving roller 91, a driven roller 92, a conveyance belt 93, and a transfer roller 94.

  The driving roller 91 and the driven roller 92 are spaced apart and arranged in parallel, and an endless conveyance belt 93 is stretched between them.

  The outer surface of the conveyor belt 93 is in contact with each photosensitive drum 611. In addition, four transfer rollers 94 that sandwich the conveyance belt 93 between the photosensitive drums 611 are arranged inside the conveyance belt 93.

  A transfer bias is applied to the transfer roller 94 in order to transfer the toner image on each photosensitive drum 611 to a sheet.

  In the transfer unit 9 configured as described above, the paper transported by the transport belt 93 at the time of image formation is transported between the photosensitive drum 611 and the transfer roller 94, and the toner image formed on each photosensitive drum 611. Is transferred to the paper.

<1-3-4 Fixing unit>
The fixing unit 10 includes a heating roller 101 disposed behind the transfer unit 9 and heated by a heat source, and a pressure roller 102 pressed against the heating roller.

  In the fixing unit 10 configured as described above, the toner image on the paper is thermally fixed to the paper as the paper passes between the heating roller 101 and the pressure roller 102.

<1-4 paper discharge unit>
The paper discharge unit 5 includes a paper discharge roller 51 for conveying the paper that has passed through the fixing unit 10 and a paper discharge tray 52 for storing the paper conveyed by the paper discharge roller 51.

  In the paper discharge unit 5 configured as described above, the paper on which the toner image is fixed by the fixing unit 10 is conveyed by the paper discharge roller 51 and discharged onto the paper discharge tray 52.

<2 Detailed description of developing cartridge>
Next, the detailed configuration of the developing cartridge 8 will be described with reference to FIG.

  The developing cartridge 8 includes a developing frame 81, a developing roller 82, and a supply roller 83.

  The development frame 81 is formed in a box shape having a substantially isosceles triangular shape in side view and extending in the left-right direction and having an apex angle toward the rear lower side, a handle portion 811, a boss 812 as an example of a pressed portion, and a drive And a unit 813.

  The handle portion 811 extends in the left-right direction at the center portion in the left-right direction of the developing frame 81 and is formed so as to protrude upward from the upper end portion of the developing frame 81.

  The boss 812 is formed in a substantially cylindrical shape projecting outward in the left-right direction on both left and right end faces of the developing frame 81. (In the following description, the right boss as an example of the second pressed portion is indicated as the right boss 812R, and the left boss as an example of the first pressed portion is indicated as the left boss 812L.)

  The drive unit 813 is provided at the left end portion of the developing frame 81 and includes a coupling member 814 as an example of a drive receiving portion, a gear train 815, and a gear cover 816.

  The coupling member 814 has a substantially cylindrical shape, and integrally includes a large-diameter gear portion 814a and a small-diameter coupling portion 814b that extends coaxially from the gear portion to the left side.

  As shown in FIG. 4, when the developing cartridge 8 is mounted in the left end portion of the coupling member 814, the main body side drive transmission unit 22 provided in the main body casing 2 is connected to the main body side drive transmission unit 22. A driving force is input from a motor (not shown) as a driving source that is connected from the left and is provided in the main casing 2.

  The gear train 815 includes a relay gear 815a and an agitator gear 815b.

  The relay gear 815 a is formed as a two-stage gear in which a large-diameter outer tooth and a small-diameter inner tooth are integrally formed on the upper side of the coupling member 814. The relay gear 815a is arranged so that its external teeth mesh with the gear portion of the coupling member 814.

  The agitator gear 815b is disposed on the front upper side of the relay gear 815a, and is disposed so as to mesh with the internal teeth of the relay gear 815a. The agitator gear 815b is provided at the left end portion of the rotation shaft of the agitator 841 that stirs the toner in the developing cartridge 8 so as not to be relatively rotatable.

  The developing roller 82 is provided at the lower end of the developing frame 81 along the left-right direction so that a part of the surface of the developing roller 82 is exposed from the opening.

  The roller shaft 821 is the axial center of the developing roller 82 and is inserted through the developing roller 82 in the left-right direction, and has a developing drive gear 821a and a color member 821b.

  The development drive gear 821a is provided at the left end portion of the roller shaft 821 so as not to be relatively rotatable.

  The collar member 821b is formed in a substantially cylindrical shape extending in the left-right direction, and is fitted on the roller shaft 821 at both ends of the roller shaft 821. The inner diameter of the collar member 821b is slightly larger than the outer diameter of the roller shaft 821.

<3 Detailed description of the drum unit>
Next, the detailed configuration of the drum unit will be described with reference to FIGS.

  The drum unit 60 includes a right side plate 62 and a left side plate 63, a front beam 64, and a rear beam 65.

<3-1-1 Right side plate>
As shown in FIG. 6, the right side plate 62 has a guide groove 621 for guiding the mounting of the developing cartridge 8 on the left side (inner side) of the right side plate 62.

  Four guide grooves 621 are formed at equal intervals in the front-rear direction so as to correspond to the respective photosensitive drums 611. Each guide groove 621 is formed in a substantially U shape in which the upper side of the corresponding photosensitive drum 611 extends obliquely from the front upper portion toward the rear obliquely lower side and the upper side is opened. The guide groove 621 is formed with a contact surface 621 a that comes into contact with the color member 821 b of the developing cartridge 8 when the developing cartridge 8 is mounted on the drum unit 60.

  As shown in FIGS. 3 and 4, a right guide rail 622, a right roller (not shown), and four right pressing members 624 as an example of a second pressing member are provided at the upper end portion of the right side plate 62. .

  The right guide rail 622 is formed as a protrusion that extends along the front-rear direction and protrudes outward in the left-right direction from the left-right outer surface of the right-side plate 62. The right guide rail 622 is formed over substantially the entire width of the right side plate 62 in the front-rear direction.

  The right roller is rotatably provided on the outer surface in the left-right direction of the right side plate 62 below the rear end portion of the right guide rail 622.

<3-1-2 Right side pressing member>
The four right pressing members 624 are provided at equal intervals in the front-rear direction. The right support shaft 625 protrudes from the inner side surface of the right side plate 62 toward the right side (inner side), and the right support shaft 625. And a right pressing spring 627 as an example of a second spring that presses the right pressing lever 626.

  The right pressing lever 626 is formed in a substantially fan shape in a side view. The right pressing lever 626 has a right contact surface 626a and a right pressing surface 626b formed continuously. The right pressing lever 626 includes a tangent line L1 passing through a contact point where the right contact surface 626a contacts the right boss 812R when the developing cartridge 8 is in the mounting position, and left pressing when the developing cartridge 8 is in the pressing position. The surface 636b and the left boss 812L are formed to have an angle α formed by a tangent line L2 passing through a contact point where the surface 636b contacts the left boss 812L. More specifically, the right pressing lever 626 is formed such that the angle α satisfies 125 ° ≦ α ≦ 140 °.

  The right contact surface 626a is a substantially arc-shaped portion in side view, and is a surface that contacts the right boss 812R of the developer cartridge 8 when the developer cartridge 8 is mounted on the drum unit 60.

  The right pressing surface 626b is a portion extending from the rear end portion of the right contact surface 626a to the right support shaft 625, and contacts the right boss 812R of the developing cartridge 8 after driving is input to the coupling member 814. This is a surface that presses the developing roller 82 toward the photosensitive drum 611 side.

  The right pressing spring 627 is a spiral spring wound around the right support shaft 625, and one end thereof is locked to the right side plate 62 and the other end is locked to the right pressing lever 626. Accordingly, the right pressing lever 626 is urged counterclockwise in FIG. 6 about the right support shaft 625.

<3-2-1 Left side plate>
In the left side plate 63, a guide groove (not shown) similar to the guide groove 621 formed in the right side plate 62 is formed on the inner side surface of the left side plate 63.

  Further, as shown in FIG. 4, the left side plate 63 has a coupling member 814 corresponding to each color and a flange exposure hole 638 and a coupling exposure hole 639 for exposing the flange portion.

  Four flange exposure holes 638 are formed at the lower end portion of the left side plate 63 at intervals from each other along the front-rear direction. The flange exposure hole 638 is formed to be a round hole penetrating in the thickness direction of the left side plate 63.

  Four coupling exposure holes 639 are formed at the lower end portion of the left side plate 63 and above the flange exposure holes 638 at intervals from each other along the front-rear direction. The coupling exposure hole 639 penetrates in the thickness direction of the left side plate 63 and is formed in a substantially round hole shape having a diameter larger than that of the coupling portion 814b. In each coupling exposure hole 639, a coupling portion 814b provided on the left side surface of the developing cartridge 8 is inserted in a state where the developing cartridge 8 is mounted on the drum frame 60.

  An upper end portion of the left side plate 63 is provided with a left guide rail 632, a left side roller 633, and four left side pressing members 634 as an example of a first pressing member.

  The left guide rail 632 is formed as a protrusion that extends along the front-rear direction and protrudes outward in the left-right direction from the left-right outer surface of the left-side plate 63. The left guide rail 632 is formed over substantially the entire width of the left side plate 63 in the front-rear direction.

  The left roller 633 is rotatably provided on the left and right outer surfaces of the left side plate 63 below the rear end portion of the left guide rail 632.

<3-2-2 Left side pressing member>
As shown in FIG. 7, the four left pressing members 634 are provided at equal intervals in the front-rear direction, and a left support shaft 635 that protrudes inward from the inner surface of the right side plate 62, A left pressing lever 636 that is swingably supported by the left support shaft 635 and a left pressing spring 637 as an example of a first pressing spring that presses the left pressing lever 636 are provided.

  The left pressing lever 636 has the same shape as the right pressing lever 626. The left pressing lever 636 has a left contact surface 636a and a left pressing surface 636b formed continuously.

  The left contact surface 636a is a substantially arc-shaped portion in side view, and is a surface that contacts the left boss 812L of the developer cartridge 8 when the developer cartridge 8 is attached to the drum unit 60.

  The left pressing surface 636b is a portion extending from the rear end portion of the left contact surface 636a to the left support shaft 635, and contacts the left boss 812L of the developing cartridge 8 after driving is input to the coupling member 814. This is a surface that presses the developing roller 82 toward the photosensitive drum 611 side.

  The left pressing spring 637 is a spiral spring wound around the left support shaft 635, and one end thereof is locked to the left side plate 63 and the other end is locked to the left pressing lever 636. Thereby, the left pressing lever 636 is urged counterclockwise in FIG. 7 about the left support shaft 635. The spring constant of the left pressing spring 637 is configured to be smaller than the spring constant of the right pressing spring 627.

  This is because the right boss 812R of the developing cartridge 8 is formed on the developing frame 81 on the side opposite to the side on which the coupling member 814 is provided in the left-right direction, so that driving is input to the coupling portion 814b. Furthermore, the pressing force that presses the left contact surface 636a of the left boss 812L is weaker than the pressing force that presses the right contact surface 626a of the right boss 812R812.

  Therefore, by making the spring constant of the right pressure spring 627 larger than the spring constant of the left pressure spring 637, the right pressure lever 626 at the mounting position of the developing cartridge 8 (see FIG. 7) is smaller than the left pressure lever 636. The right boss 812R is easily moved to the right pressing surface 626b because it is easily rotated by pressure.

  In the state where the developing cartridge 8 is disposed at the pressing position (see FIG. 8), the pressing force for pressing the right boss 812R of the right pressing surface 626b is substantially the same as the pressing force for pressing the left boss 812L of the left pressing surface 636b. equal.

<3-3 Front beam and rear beam>
As shown in FIG. 4, the front beam 64 includes a connecting portion 641 extending substantially vertically and a front gripping portion 642 gripped by the user.

  The front gripping portion 642 has a substantially U shape in plan view and is formed integrally with the connecting portion 641. Further, the front gripping part 642 is formed so as to protrude to the front side of the connecting part 641.

  A rear grip 651 that is gripped by the user is integrally formed at the center in the left-right direction of the rear beam 65.

  The rear grip 651 is substantially U-shaped in rear view, and is formed so as to incline from the rear lower side to the rear upper side.

  The user can slide the process unit 6 in the front-rear direction with respect to the main body casing 2 by holding the front side holding portion 642 while the front cover 21 is opened. The user grips the front gripping portion 642 and the rear gripping portion 651 in a state where the rear gripping portion 651 is pulled out until the rear gripping portion 651 is positioned on the front side of the front end portion of the main body casing 2, and the process unit 6 is moved to the main body. The casing 2 can be detached.

<4 Development cartridge attachment / detachment operation>
Next, the operation of moving the developing cartridge 8 from the mounting position to the pressing position will be described with reference to FIGS.

  When the user attaches the developing cartridge 8 to the drum unit 60, as shown in FIG. 7, the boss 812 formed on the side surface of the developing frame 81 contacts the right contact surface 626a and the left contact surface 636a, and the developing cartridge 8 Is placed at the mounting position.

  When the user moves the process unit 6 to the inner position in the main casing 2, the coupling portion 814 a and the flange portion 611 a are connected to the main body side drive transmission portion 22 provided in the main casing 2 as shown in FIG. 4. Move to the opposite position.

  When the user closes the front cover 21, the drive source (not shown) provided in the main body casing 2 moves the main body side drive transmission portion 22 to the right, and the coupling portion 814a and the flange portion 611a Engage. As a result, the photosensitive drum 611 and the developing roller 82 can be driven to rotate by the motor. Moreover, the rotation direction of the coupling part 814a and the flange part 611a is comprised so that it may rotate clockwise in FIG.

  When driving is input from the main body side drive transmission unit 22 to the coupling unit 814 a, the color member 821 b of the developing roller 82 is engaged with the contact surface 621 of the guide groove 621 in the developing cartridge 8. In FIG. 3, a rotational moment is generated in the clockwise direction around the rotational axis of the developing roller 82. Therefore, the developing cartridge 8 rotates in the clockwise direction with the rotation axis of the developing roller 82 as the rotation center.

  At this time, the boss 812 of the developing cartridge 8 presses the right contact surface 626a and the left contact surface 636a in the forward direction. Then, both pressing levers move in the clockwise direction against the spring force of both pressing springs. Then, as shown in FIG. 8, the developing cartridge 8 rotates to a position where the boss 812 is pressed by the right pressing surface 626b and the left pressing surface 636b while being in contact with the right contacting surface 626a and the left contacting surface 636a. .

<5 action and effect>
The operational effects of the color laser printer configured as described above will be described.

(Claim 1)
According to the color laser printer 1, a right side pressing member 624 and a left side pressing member 634 that press the boss 812 of the developing cartridge 8 are provided at the upper end portion of the drum unit 60.

  The right pressing member 624 develops when the drive is input to the right contact surface 626a that contacts the right boss 812R of the developing cartridge 8 and the coupling member 814 when the developing cartridge 8 is mounted on the drum unit 60. It has a right pressing lever 626 formed with a right pressing surface 626b that contacts the right boss 812R of the cartridge 8 and presses the developing roller 82 toward the photosensitive drum 611.

  The left pressing member 634 is provided when the drive is input to the left contact surface 636a that contacts the left boss 812L of the developing cartridge 8 and the coupling member 814 when the developing cartridge 8 is mounted on the drum unit 60. The left pressing lever 636 is formed with a left pressing surface 636b that contacts the left boss 812L of the developing cartridge 8 and presses the developing roller 82 toward the photosensitive drum 611.

  The right abutment surface 626a and the left abutment surface 636a move the boss 812 relative to the right pressing surface 626b and the left pressing surface 636b when the drive is not input from the main body side drive transmission portion 22 to the coupling portion 814b. Instead, when the drive is input to the coupling portion 814b, the boss 812 is inclined so as to move to a position where it abuts on the right pressing surface 626b and the left pressing surface 636b.

  As a result, the developing cartridge 8 moves to the pressing position when driving is input to the coupling member 814. Therefore, the developing cartridge 8 can be reliably mounted at an appropriate position while the process unit 6 is at the inner position. it can. Further, when the drive is input to the coupling member 814, the developing cartridge 8 automatically moves to an appropriate position, so that it is not necessary for the user to mount the developing cartridge at an appropriate position, which is easy to use.

(Claim 2)
Further, according to this color laser printer 1, since the right pressing member 624 and the left pressing member 634 press the right boss 812R and the left boss 812L of the developing cartridge 8, the developing roller 82 covers the entire area of the photosensitive drum 611 in the left-right direction. Press evenly. As a result, it is possible to suppress printing defects due to the development roller 82 being separated from the photosensitive drum 611.

(Claim 3)
Further, according to this color laser printer 1, the right pressing member 624 has the right pressing spring 627 that is larger than the spring constant of the left pressing spring 637.

  With such a configuration, the right pressing lever 626 at the mounting position of the developing cartridge 8 is easily rotated with a pressing force smaller than that of the left pressing lever 636. As a result, the right boss 812R on the side opposite to the side where the coupling member 814 is provided in the left-right direction is likely to move to the right pressing surface 626b.

(Claim 6)
Further, according to the color laser printer 1, the developing cartridge 8 is configured such that the coupling portion 814 b is disposed in the vicinity of the roller shaft 821 of the developing roller 82.

  With such a configuration, when the developing cartridge 8 rotates, the range in which the coupling portion 814 rotates can be reduced.

  As a result, when the developing cartridge 8 rotates, it is possible to prevent the main body side drive transmission unit 22 and the coupling unit 814 from being disconnected.

(Claim 7)
Further, according to the color laser printer 1, since the developing cartridge 8 is configured to be detachable from the drum unit 60, only the developing cartridge 8 can be replaced.

(Claim 9)
Further, according to the color laser printer 1, the process unit 6 includes a plurality of photosensitive drums 611, a plurality of developing cartridges 8, and a plurality of right pressing members 624 and left pressing members 634 corresponding to the plurality of developing cartridges 8. Thus, the plurality of developing cartridges 8 can be mounted at appropriate positions at the same time.

<Modification>
(Claim 4)
In the above-described embodiment, the right pressure lever 626 and the left pressure lever 636 have the same shape. For example, as shown in FIG. 10, the right pressure lever 626 and the left pressure lever 636 have different shapes. May be. FIG. 10 shows a state where the developing cartridge is arranged at the mounting position.

  More specifically, as shown in FIG. 10A, the left pressing lever 636 is a tangent passing through a contact point where the left contact surface 636a and the left boss 812L contact when the developing cartridge 8 is in the mounting position. It is formed so as to have an angle α between a tangent L2 passing through a contact point where the left pressing surface 636b and the left boss 812L contact when L1 and the developing cartridge 8 are in the pressing position.

  Further, as shown in FIG. 10B, the right pressing lever 726 is connected to the tangent line L3 passing through the contact point where the right contact surface 726a and the right boss 812R contact when the developing cartridge 8 is in the mounting position. Is formed at an angle α formed by a tangent line L4 passing through a contact point where the right pressing surface 726b and the right boss 812R are in contact with each other. The right pressing lever 726 is formed such that the angle β is larger than the angle α. More specifically, the right pressing lever 726 is formed such that the angle β formed is 140 ° <α ≦ 150 °.

  With such a configuration, the right boss 812R of the developing cartridge 8 is easily moved to a position where it abuts on the right pressing surface 726b of the right pressing lever 726.

(Claim 8)
In the above-described embodiment, the process unit 6 includes the drum unit 60 that supports the photosensitive drum 611 and the developing cartridge 8 that is detachable from the drum unit 60. For example, FIG. As illustrated, the process unit 12 may include a plurality of process cartridges 122 in which the developing roller 82 and the photosensitive drum 611 are integrated, and a process frame 121 that integrally supports the plurality of process units. In FIG. 11, only the left side surface of the process unit 12 is shown.

  More specifically, the process unit 12 includes four process cartridges 122 corresponding to the respective colors, and a process frame 121 that integrally supports the four process cartridges.

  The process frame 121 has a substantially rectangular shape in plan view.

  The left side plate 63 of the process frame 121 has a coupling exposure hole 639 for exposing the coupling member 814 of the process cartridge corresponding to each color.

  In the process cartridge 122, a photosensitive drum 611, a photosensitive unit 123 including a charger 612, a developing roller 82, and a developing unit 125 including a supply roller 83 are integrally provided. Further, the process cartridge 122 is detachably attached to the process frame 121.

  The photosensitive unit 123 includes a drum frame 124 that rotatably supports the photosensitive drum 611, and includes protrusions 124 a that protrude outward in the left-right direction from both side surfaces of the drum frame 124, and a pressing spring 124 b that presses the developing unit 125. Have.

  The pressing spring 124b is a spiral spring wound around the protruding portion 124a, and as shown in FIG. 7, biases the developing unit 125 counterclockwise around the protruding portion 124a. As a result, the developing roller 82 does not come into contact with the photosensitive drum 611 when the process cartridge 122 is not mounted at an appropriate position.

  The developing unit 125 includes a developing frame 126 that rotatably supports the developing roller 82 and the supply roller 83, a support hole that engages with the protruding portion 124 a, a coupling member 814 that transmits driving to the developing roller 82, and a right pressing And a boss 812 that receives pressure from the lever 626 and the left pressure lever 636.

  The boss 812 is formed on the opposite side of the support hole across the coupling member 814 in the front-rear direction so as to extend outward from the both sides of the developing frame 126 in the left-right direction.

  Also in the process unit 12 configured in this way, the same effect as that of the present embodiment can be obtained.

(Claim 10)
In the above-described embodiment, the right pressing member 624 and the left pressing member 634 have the right contact surface 626a, the right pressing surface 626b, the left contact surface 636a, and the left pressing surface 636b. As shown in FIG. 12, the developing frame has a right contact surface 137b, a right pressed surface 137a having the same shape as the right contact surface 626a, the right pressure surface 626b, the left contact surface 636a, and the left pressure surface 636b. You may have the left side contacted surface 147b and the left side pressed surface 147a. In FIG. 12, only the left side surface of the process unit 13 is shown.

  More specifically, the process unit 13 includes four process cartridges 132 corresponding to the respective colors and a process frame 131 that integrally supports the four process cartridges 132.

  The process frame 131 has a substantially rectangular shape in plan view.

  The left side plate 63 of the process frame 131 has a coupling exposure hole 639 for exposing the coupling portion 814b of the process cartridge 132 corresponding to each color.

  The process cartridge 132 includes a photosensitive cartridge 133 including a photosensitive drum 611 and a charger 612, and a developing cartridge 135 configured to be detachable from the photosensitive cartridge 133, and including a developing roller 82 and a supply roller 83. ing. The process cartridge 132 is detachably attached to the process frame 131.

  The photoreceptor cartridge 133 has a drum frame 134 that rotatably supports the photosensitive drum 611 on one end side, and a right pressing member 134R and a left pressing member 134L that press the developing frame 136 of the developing cartridge 135.

  The developing cartridge 135 includes a developing frame 136 that rotatably supports the developing roller 82 and the supply roller 83 on one end side, and a coupling member 814 that transmits driving to the developing roller 82.

  On the other end side of the developing frame 136, a right pressed portion 137 and a left pressed portion 147 are formed as an example of a pressed portion that receives pressure from the right pressing member 134R and the left pressing member 134L.

  The left pressed portion 147 includes a left pressed surface 147a that receives pressure from the left pressing member 134L, and a left pressed surface 147b that contacts the left pressing member 134L in a state in which the pressure from the left pressing member 134L is released. Have.

  Also in the process unit 13 configured in this way, the same effect as that of the present embodiment can be obtained.

(Claim 5)
Further, in the above-described embodiment, the pressing force with which the right pressing spring 627 presses the right pressing lever 626 with the developing cartridge 8 disposed at the pressing position is the left pressing spring 637 pressing the left pressing lever 636-. However, the pressing force with which the right pressing spring 627 presses the right pressing lever 626 may be smaller than the pressing force with which the left pressing spring 637 presses the left pressing lever 636. .

  With such a configuration, the right boss 812R of the developing cartridge 8 provided on the side opposite to the side on which the coupling member 814 is provided is easily moved to a position where it abuts on the right pressing surface 626b.

  In the above-described embodiment, the boss 812 is formed to extend outward in the left-right direction from both side surfaces of the developing frame 81. However, for example, the boss 812 may be formed to extend outward from the gear cover 816 in the left-right direction.

  In the above-described embodiment, the color laser printer has been described. However, the same effect as that of the embodiment can be obtained even in a monochrome laser printer.

  Further, in the above-described embodiment, the developing cartridge 8 is configured to rotate when the driving is input to the coupling member 814 for transmitting the driving to the developing roller 82. In the process cartridge in which the development unit is integrated, the process cartridge may be rotated when the drive is input to the coupling member for transmitting the drive to the photosensitive drum.

DESCRIPTION OF SYMBOLS 1 ... Color laser printer, 2 ... Main body casing, 21 ... Front cover, 22 ... Main body side drive transmission part, 23 ... Opening, 4 ... Image formation part, 6 ... Process unit 60 ... Drum unit 61 ... Drum subunit 611 ... Photosensitive drum 62 ... Right side plate 624 ... Right pressing member 625 ... Right support shaft 626 ...・ Right side pressure lever, 626a ... Right side contact surface, 626b ... Right side pressure surface, 627 ... Right side pressure spring, 63 ... Left side plate, 634 ... Left side pressure member, 635 ... Left side Support shaft, 636... Left pressing lever, 636a... Left contact surface, 636b... Left pressing surface, 637. 812 ... Bo , 814 ... coupling member, 82 ... developing roller, 821 ... roller shaft

Claims (18)

The device body;
A photosensitive unit including a photosensitive member; a developing unit including a developing roller and a pressed portion; and a pressing member that presses the pressed portion of the developing unit so that the developing roller is pressed against the photosensitive member. A movable member configured to be movable between an inner position located at an inner position of the apparatus main body and an outer position of the apparatus main body,
A drive member for transmitting drive to the drive receiving portion of the photosensitive unit or the development unit when the moving member is located at the inner position;
The developing unit is
The movable member is configured to be swingable between a first posture in which the pressed portion is pressed by the pressing member and a second posture in which the pressing of the pressing member is released,
The pressing member is
A pressing surface that presses the pressed portion in the first posture; and a contact surface that contacts the pressed portion in the second posture;
The contact surface is
When no driving force is input from the driving member to the driving receiving portion with respect to the pressing surface, the pressed portion does not move and driving force is input from the driving member to the driving receiving portion. In some cases, the image forming apparatus is inclined so that the pressed portion moves to a position where the pressed portion comes into contact with the pressing surface. The pressed portion is
A first pressed portion provided on one side of the developing unit in the rotation axis direction of the photoconductor;
A second pressed portion provided on the other side in the rotation axis direction of the developing unit,
The pressing member is
A first pressing member that is provided on one side in the rotational axis direction of the moving member and presses the first pressed portion;
The image forming apparatus according to claim 1, further comprising: a second pressing member that is provided on the other side in the rotation axis direction of the pressing member and presses the second pressed portion. The drive receiving portion is
Provided on one end side in the rotational axis direction of the photosensitive unit or the developing unit;
The first pressing member has a first spring,
The second pressing member is
The image forming apparatus according to claim 2, further comprising a second spring having a spring constant larger than that of the first spring. The drive receiving portion is
Provided on one side in the rotational axis direction of the photosensitive unit or the developing unit;
The second pressing member is
The angle formed between the pressing surface of the second pressing member and the contact surface is formed to be larger than the angle formed between the pressing surface of the first pressing member and the contact surface. The image forming apparatus according to claim 2, wherein the image forming apparatus is an image forming apparatus. The drive receiving portion is
Provided on one end side in the rotational axis direction of the photosensitive unit or the developing unit;
The second pressing member is
The image forming apparatus according to claim 2, wherein a pressing force is smaller than that of the first pressing member. The developing unit is
The center of oscillation of the developing unit is configured to be coaxial with the center of rotation of the developing roller,
The drive receiving portion is
The image forming apparatus according to claim 1, wherein the image forming apparatus is disposed at a position close to a rotation shaft of the developing roller. The moving member is
The image forming apparatus according to claim 1, wherein the developing unit is configured to be detachable from the moving member when the developing unit is in the second posture. The developing unit and the photoreceptor unit are:
An integrally constructed process cartridge;
The moving member is
The image forming apparatus according to claim 1, wherein the process cartridge is configured to be detachable from the moving member when the process cartridge is in the second posture. The moving member is
A plurality of photoreceptor units;
A plurality of developing units corresponding to the plurality of photosensitive units;
A plurality of pressing members corresponding to the plurality of developing units;
9. The image forming apparatus according to claim 1, further comprising: The device body;
A photosensitive unit including a photosensitive member; a developing unit including a developing roller and a pressed portion; and a pressing member that presses the pressed portion of the developing unit so that the developing roller is pressed against the photosensitive member. A movable member configured to be movable between an inner position located at an inner position of the apparatus main body and an outer position of the apparatus main body,
A drive member for transmitting drive to the drive receiving portion of the photosensitive unit or the development unit when the moving member is located at the inner position;
The developing unit is
The movable member is configured to be swingable between a first posture in which the pressed portion is pressed by the pressing member and a second posture in which the pressing of the pressing member is released,
The pressed portion is
A pressed surface that receives pressure from the pressing member in the first posture, and a pressed surface that contacts the pressing portion in the second posture;
The contacted surface is
When no driving force is input from the driving member to the driving receiving portion with respect to the pressed surface, the pressing member does not move and driving force is input from the driving member to the driving receiving portion. In some cases, the image forming apparatus is inclined so that the pressing member moves to a position in contact with the pressed surface. The pressed portion is
A first pressed portion provided on one side of the developing unit in the rotation axis direction of the photoconductor;
A second pressed portion provided on the other side in the rotation axis direction of the developing unit,
The pressing member is
A first pressing member that is provided on one side in the rotational axis direction of the moving member and presses the first pressed portion;
The image forming apparatus according to claim 10, further comprising: a second pressing member that is provided on the other side of the pressing member in the rotation axis direction and presses the second pressed portion. The drive receiving portion is
Provided on one end side in the rotational axis direction of the photosensitive unit or the developing unit;
The first pressing member has a first spring,
The second pressing member is
The image forming apparatus according to claim 10, further comprising a second spring having a spring constant larger than that of the first spring. The drive receiving portion is
Provided on one side in the rotational axis direction of the photosensitive unit or the developing unit;
The second pressed portion is
An angle formed between the pressed surface of the second pressed part and the contacted surface is larger than an angle formed between the pressed surface of the first pressed part and the contacted surface. The image forming apparatus according to claim 11, wherein the image forming apparatus is formed as follows. The drive receiving portion is
Provided on one end side in the rotational axis direction of the photosensitive unit or the developing unit;
The second pressing member is
The image forming apparatus according to claim 11, wherein a pressing force is smaller than that of the first pressing member. The developing unit is
The center of oscillation of the developing unit is configured to be coaxial with the center of rotation of the developing roller,
The drive receiving portion is
The image forming apparatus according to claim 10, wherein the image forming apparatus is disposed at a position close to a rotation shaft of the developing roller. The moving member is
The image forming apparatus according to claim 10, wherein the developing unit is configured to be detachable from the moving member when the developing unit is in the second posture. The developing unit and the photoreceptor unit are:
An integrally constructed process cartridge;
The moving member is
The image forming apparatus according to claim 10, wherein the process cartridge is configured to be detachable from the moving member when the process cartridge is in the second posture. The moving member is
A plurality of photoreceptor units;
A plurality of developing units corresponding to the plurality of photosensitive units;
A plurality of pressing members corresponding to the plurality of developing units;
The image forming apparatus according to claim 10, further comprising: