WO2014010130A1

WO2014010130A1 - Photosensitive body cartridge, process cartridge, and image formation device

Info

Publication number: WO2014010130A1
Application number: PCT/JP2012/080842
Authority: WO
Inventors: 進佐久間
Original assignee: ブラザー工業株式会社
Priority date: 2012-07-09
Filing date: 2012-11-29
Publication date: 2014-01-16
Also published as: CN104428722A; CN104428722B; JP5900201B2; JP2014016499A

Abstract

Provided are: a photosensitive body cartridge that can clean a charging wire while suppressing changes to the relative positioning of a charger and a photosensitive body; a process cartridge; and an image formation device provided with same. A drum cartridge (18) is provided with a photosensitive drum (20) and a scorotron-type charger (22), and a paper discharge opening (49) neighbors a charger support (90) that supports the scorotron-type charger (22). A cleaner holding unit (118) that holds a cleaning member (117) for cleaning the charging wire (23) of the scorotron-type charger (22) when moving the cleaning member (117) protrudes in a direction perpendicular to the direction along the line (R) passing through the charging wire (23) and the axial center of the photosensitive drum (20) in a projection in the left-right direction.

Description

Photosensitive cartridge, process cartridge, and image forming apparatus

The present invention relates to an image forming apparatus such as a laser printer, and a process cartridge and a photoreceptor cartridge provided in the image forming apparatus.

2. Description of the Related Art As an image forming apparatus, as described in Patent Document 1, a printer that includes a cartridge that holds a charger detachably is known.

As a cartridge that is detachably provided in such a printer, a process unit including a photosensitive cartridge that holds a photosensitive drum, a transfer roller, and a charger has been proposed.

In such a process unit, the sheet is discharged from an opening formed in the photosensitive cartridge after a visible image made of a developer is transferred between the photosensitive drum and the transfer roller.

In addition, adhering material such as paper dust and dust attached to the charging wire of the charger is moved along the charging wire while the user presses the cleaning member provided on the opposite side of the photosensitive drum against the charging wire with a finger. It is removed by operating.

JP 2000-250310 A

In recent years, downsizing of printers is desired, and accordingly, downsizing of process units and photoreceptor cartridges attached to the printers is also desired.

However, when downsizing the above-described photoreceptor cartridge, there is a limit to downsizing the size of the photoreceptor drum, the transfer roller, the charger, and the opening. On the other hand, if the case in which they are provided is reduced in size, the ratio of the opening to the case increases and there is a problem that the strength of the case decreases.

In particular, when cleaning the charging wire, the user operates while pressing the cleaning member with his / her finger, so that the case supporting the cleaning member bends, a load is applied to the charging wire and grid of the charger, and the charger and the photosensitive member The relative arrangement may change.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a photosensitive member cartridge and a process cartridge that can clean the charging wire while suppressing the relative arrangement of the charger and the photosensitive member from being changed, and an image forming apparatus including them. There is.

(1) In order to achieve the above-described object, a photoconductor cartridge of the present invention includes a casing, a rotatable photoconductor configured to carry a developer image on a peripheral surface, A transfer member disposed opposite to the circumferential surface for transferring the developer image from the circumferential surface of the photosensitive member to the recording medium and opposed to the circumferential surface of the photosensitive member at an interval so as to charge the surface of the photosensitive member. The charger is configured to extend along the axial direction of the photosensitive member, and the charging wire is configured to charge the photosensitive member by corona discharge. The charging wire is rubbed against the charging wire. A cleaning member for cleaning the charging wire, and a gripping part configured to grip when the cleaning member is moved, and the housing rotatably supports the transfer member Transfer member support and a belt for supporting the charger A first support for passing a recording medium formed between the charger support and the charger support and the transfer member support and discharged from the facing portion where the photosensitive member and the transfer member face each other; The first opening is adjacent to the charger support portion on the upstream side in the rotation direction of the photosensitive member, and the gripping portion follows a straight line passing through the axial center of the photosensitive member and the charging wire when projected in the axial direction. It protrudes in the direction that intersects the direction.

According to such a configuration, since the first opening is disposed adjacent to the charger support portion in the housing, the housing can be reduced in size.

On the other hand, when the size of the casing is reduced, the strength of the charger support portion may decrease. However, according to the above configuration, the gripping portion is gripped and the cleaning member is moved along the charging wire. be able to.

That is, since the force for gripping the grip portion and moving the cleaning member acts along the charging wire, the charging wire can be cleaned without applying a load to the charger support portion.

Further, even when a force acts in the direction opposite to the protruding direction of the gripping part at the time of cleaning, the direction is an intersecting direction that intersects a direction along a straight line passing through the axial center of the photosensitive member and the charging wire. It is possible to suppress a change in the relative arrangement of the charger and the photoconductor in the direction along the straight line.

As a result, the charging wire can be cleaned while suppressing the relative arrangement of the charger and the photoconductor from being changed.
(2) Further, the housing has a first frame disposed on the charger side in a direction along a straight line passing through the charger and the photoconductor with respect to the photoconductor, and a charger with respect to the photoconductor. And a second frame disposed on the opposite side of the charger in a direction along a straight line passing through the photoconductor, and the first opening may be formed in the first frame.

According to such a configuration, since the first opening is formed in the first frame, the first opening is compared with the case where the first opening is formed by combining the first frame and the second frame. The position can be stabilized.
(3) The first frame includes a charger support portion and a first transfer member support portion, and the second frame includes a second transfer member support portion, and the first transfer member support portion and the second transfer portion. A transfer member support part may be formed by combining with a member support part.

According to such a configuration, the transfer member support portion can be formed with a simple configuration in which the first frame including the charger support portion and the second frame are combined.
(4) The charger support portion may include a plate-like member formed over the axial direction of the charging wire so as to be able to face the grip portion.

According to such a configuration, since the charger support portion includes the plate-like member formed over the axial direction of the charging wire, the rigidity of the charger support portion can be improved.

Therefore, the rigidity of the charger support portion can be maintained even when a load acts on the charger support portion when cleaning the charging wire.

As a result, the charging wire can be cleaned while reliably maintaining the relative arrangement of the charger and the photosensitive member.
(5) Further, the plate-like member is provided on the photosensitive member side with respect to the grip portion in the direction along the straight line passing through the charger and the photoconductor, and from the charger support portion rather than the grip portion in the crossing direction. It may be protruding.

According to such a configuration, since the plate-like member that protrudes from the charger support portion relative to the grip portion is disposed on the photoconductor side relative to the grip portion, the grip portion and the photoconductor are prevented from contacting each other. be able to.

Therefore, when the user grips the grip portion, the charging wire can be cleaned by gripping the grip portion without touching the photosensitive member.
(6) Further, the free end portion of the plate-like member is arranged at a position protruding from the charger support portion rather than the photoconductor when projected in a direction along a straight line passing through the charger and the photoconductor. Also good.

According to such a configuration, since the free end portion of the plate-like member is disposed at a position protruding from the charger support portion rather than the photosensitive member, in a direction along a straight line passing through the charger and the photosensitive member. Light from the gripping part side can be shielded.

Therefore, the quality of the photoreceptor can be maintained.
(7) The housing further includes a bottom wall formed on the opposite side of the charger with respect to the photoreceptor, and the bottom wall and the transfer member support portion are supplied to the facing portion between them. A second opening for allowing the recording medium to pass therethrough may be formed.

According to such a configuration, it is possible to easily ensure the accuracy of the relative arrangement of the second opening with respect to the facing portion.

Therefore, the recording medium can be reliably passed through the second opening and supplied to the facing portion.
(8) A process cartridge according to the present invention includes the above-described photosensitive cartridge and a developing cartridge that contains a developer and is configured to be detachable from the photosensitive cartridge. The photosensitive cartridge is rotated by the developing cartridge. The developing cartridge includes a contact portion that comes into contact with the plate-like member when detached from the cartridge storage portion.

According to such a configuration, the contact portion of the developing cartridge comes into contact with the plate-like member when detached from the cartridge housing portion.

Therefore, the gripping portion can be protected by the plate-shaped member when the developing cartridge is detached.

As a result, it is possible to suppress the load from acting on the charging wire and the grid that are cleaned by holding the holding portion and moving the cleaning member.
(9) The image forming apparatus of the present invention includes the above-described process cartridge, and a fixing device that fixes the developer image on the recording medium is disposed downstream of the process cartridge in the recording medium conveyance direction.

According to such a configuration, an air flow is generated toward the fixing device due to heat generation of the fixing device.

In this case, when the surface of the photoconductor is charged, the airflow generated from the charger toward the photoconductor hits the surface of the photoconductor, so that the developer adhering to the photoconductor is scattered and the rotation direction of the photoconductor Is separated into the downstream side and the upstream side.

Then, the airflow that has flowed to the upstream side is returned to the airflow toward the fixing device together with the developer scattered near the charger.

However, since a plate-like member is formed on the charger support portion, it is possible to prevent the airflow from flowing along with the scattered developer toward the charger.

As a result, it is possible to prevent the developer scattered from the charger from entering.
(10) Further, the developing cartridge includes a developer carrying member facing the photoconductor when mounted in the cartridge housing portion, and the charger, the transfer member, and the developer carrying member are projected in the axial direction. Sometimes, the angle formed by the first imaginary line connecting the axial center of the photosensitive member and the charging wire and the second imaginary line connecting the axial center of the photosensitive member and the axial center of the transfer member, the second imaginary line, and the photosensitive member The angle formed by the third imaginary line connecting the axis center of the developer and the axis center of the developer carrying member and the angle formed by the third imaginary line and the first imaginary line are substantially the same. May be.

According to such a configuration, since the charger, the developer carrier, and the transfer member are arranged substantially equally around the photoreceptor, the surface of the photoreceptor is charged by the charger, and the developer carrier is provided. Thus, a series of operations of forming a developer image on the surface of the photosensitive member and transferring the developer image to the recording medium together with the transfer member can be stably performed with good balance.

In the photosensitive member cartridge, the process cartridge, and the image forming apparatus of the present invention, the charging wire can be cleaned while the relative arrangement of the charger and the photosensitive member is suppressed from being changed while the size can be reduced.

FIG. 1 is a side sectional view showing a printer according to a first embodiment of an image forming apparatus of the present invention. FIG. 2 is an explanatory view for explaining attachment and detachment of the developing cartridge shown in FIG. 1 with respect to the drum cartridge, wherein (a) is a left sectional view in a state where the developing cartridge is mounted, and (b) FIG. 4 is a left side view of the developing cartridge mounted. FIG. 3 is an explanatory view for explaining attachment and detachment of the developing cartridge to / from the drum cartridge following FIG. 2, wherein (a) is a left side sectional view in a state where the developing cartridge is detached, and (b) FIG. 4 is a left side view of the developing cartridge in a detached state. 4 is an exploded side sectional view of the drum frame shown in FIG. FIG. 5 is an exploded perspective view of the drum cartridge shown in FIG. 2 as viewed from the left rear side. 6 is an exploded perspective view of the cover frame shown in FIG. 5 as viewed from the left front side. FIG. 7 is a left sectional view of the process cartridge according to the printer of the second embodiment of the image forming apparatus of the present invention.

1. Overall Configuration of Printer As shown in FIG. 1, a printer 1 as an example of an image forming apparatus includes a substantially box-shaped main body casing 2.

In addition, the printer 1 includes a sheet feeding unit 3 for feeding a sheet S as an example of a recording medium and an image forming unit 4 for forming an image on the fed sheet S in the main body casing 2. It has.

In addition, when referring to the direction with respect to the printer 1, the direction when placed in the horizontal direction is used as a reference, and specifically, the direction of the arrow in the drawing is used as a reference.
(1) Main Body Casing The main body casing 2 is formed with a cartridge opening 5 for attaching / detaching a process cartridge 15 (described later) and a paper opening 6 for introducing the paper S.

The cartridge opening 5 is formed through the upper end of the main casing 2 in the vertical direction.

The paper opening 6 is formed to penetrate in the front-rear direction at the lower end of the front end of the main casing 2.

Further, the main body casing 2 is provided with a top cover 7 at its upper end and a paper feed cover 8 at its front end. The top cover 7 is provided with a paper discharge tray 41 from which the paper S is discharged.

The top cover 7 is provided to be swingable (movable) between a closed position for closing the cartridge opening 5 and an open position for opening the cartridge opening 5 with the rear end as a fulcrum.

The paper feed cover 8 is swingably (moved) between a first position where the paper opening 6 is closed and a second position where the paper opening 6 is opened with the lower end of the paper supply cover 8 as a fulcrum.
(2) Paper Feed Unit The paper feed unit 3 includes a paper placement unit 9 provided at the bottom of the main casing 2.

The paper stacking portion 9 is communicated with the outside of the main casing 2 through the paper opening 6.

The sheet S is stacked on the upper surface of the sheet feed cover 8 while the sheet feed cover 8 is disposed at the second position, and the rear part is loaded on the sheet via the sheet opening 6. Stacked in the placement unit 9.

The paper feeding unit 3 includes a pickup roller 11 disposed on the upper side of the rear end portion of the paper placing unit 9, a paper feeding roller 12 disposed on the rear side of the pickup roller 11, and a rear lower side of the paper feeding roller 12. The sheet feeding pad 13 is disposed opposite to the sheet feeding side, and the sheet feeding path 14 extends continuously upward from the rear end portion of the sheet feeding pad 13.
(3) Image Forming Unit The image forming unit 4 includes a process cartridge 15, a scanner unit 16, and a fixing unit 17 as an example of a fixing device.
(3-1) Process Cartridge The process cartridge 15 is configured to be detachable from the main casing 2 and is mounted on the main casing 2 above the rear portion of the paper feed unit 3.

The process cartridge 15 includes a drum cartridge 18 as an example of a photosensitive cartridge configured to be detachable from the main body casing 2, and a developing cartridge 19 configured to be detachable from the drum cartridge 18.

The drum cartridge 18 includes a photosensitive drum 20 as an example of a photosensitive member, a transfer roller 21 as an example of a transfer member, and a scorotron charger 22 as an example of a charger.

The photosensitive drum 20 is formed in a substantially cylindrical shape that is long in the left-right direction, and is provided rotatably at the rear portion of the drum cartridge 18.

The transfer roller 21 is formed in a substantially cylindrical shape extending in the left-right direction, and is rotatably provided at the rear portion of the drum cartridge 18 so as to be pressed against the photosensitive drum 20 from the rear side.

Specifically, the transfer roller 21 is disposed on the rear side of the photosensitive drum 20 so that the axial center thereof is positioned slightly below the axial center of the photosensitive drum 20. The lower end edge of the transfer roller 21 is disposed above the lower end edge of the photosensitive drum 20. Specifically, an imaginary line segment (not shown) connecting the axis center of the transfer roller 21 and the axis center of the photosensitive drum 20 and an imaginary straight line (not shown) extending horizontally along the front-rear direction are formed. The acute angle formed is about 3 °. Therefore, the pressure (transfer pressure) at which the transfer roller 21 is pressed against the photosensitive drum 20 is not affected by the weight of the transfer roller 21.

The scorotron charger 22 is disposed opposite to the front upper side of the photosensitive drum 20 with an interval.

Specifically, the scorotron charger 22 is disposed with a space in the circumferential direction of the photosensitive drum 20 with respect to the transfer roller 21, and is an imaginary link between the axial center of the photosensitive drum 20 and the axial center of the transfer roller 21. And an imaginary line segment (not shown) connecting the axial center of the photosensitive drum 20 and the charging wire 23 (described later) is about 120 °. Has been placed.

The scorotron charger 22 includes a charging wire 23 and a grid 24.

The charging wire 23 is stretched so as to extend in the left-right direction, and is opposed to the front upper side of the photosensitive drum 20 with an interval.

The grid 24 is formed in a substantially U shape in a side view opened toward the front upper side, and is provided so as to surround the charging wire 23 from the lower back side.

The developing cartridge 19 is disposed on the lower front side of the photosensitive drum 20 and includes a developing frame 25.

In the developing frame 25, a toner storage chamber 26 and a developing chamber 27 are formed side by side. The toner storage chamber 26 and the developing chamber 27 are formed to have substantially the same volume, and communicate with each other through a communication port 28.

The toner storage chamber 26 stores toner (developer), and an agitator 29 is provided at a substantially central portion in the front-rear and vertical directions. That is, the agitator 29 is disposed below the photosensitive drum 20.

In the developing chamber 27, a supply roller groove 30, a developing roller facing surface 31, and a lower film attaching surface 32 are formed on the upper surface of the lower wall.

The supply roller groove 30 has a substantially semicircular shape along the peripheral surface of a supply roller 33 (described later), and is formed so as to be recessed downward in the rearward direction.

The developing roller facing surface 31 has a substantially arc shape along the peripheral surface of the developing roller 34 (described later), and is formed so as to continuously extend rearward from the rear end portion of the supply roller groove 30.

The lower film attaching surface 32 is formed so as to continuously extend rearward from the rear end portion of the developing roller facing surface 31. That is, the lower film attaching surface 32 is disposed above the developing roller facing surface 31.

Further, the lower film attachment surface 32 is disposed to face the lower portion of the photosensitive drum 20 with a space in the vertical direction, and overlaps the axial center of the photosensitive drum 20 when projected in the vertical direction. Is arranged.

In the developing chamber 27, a supply roller 33, a developing roller 34 as an example of a developer carrier, a layer thickness regulating blade 35, and a lower film 36 are provided.

The supply roller 33 is rotatably provided in the front portion of the developing chamber 27 so that the lower portion thereof is disposed in the supply roller groove 30. Thus, the supply roller 33 is disposed on the rear side of the toner storage chamber 26 and is disposed at substantially the same height as the toner storage chamber 26 in the vertical direction.

The developing roller 34 includes a metal developing roller shaft 52 extending in the left-right direction and a rubber roller 53 that covers the developing roller shaft 52 so that both left and right ends of the developing roller shaft 52 are exposed.

The developing roller 34 is rotatably provided in the rear portion of the developing chamber 27 so that the peripheral surface of the lower portion of the rubber roller 53 and the developing roller facing surface 31 face each other with a space therebetween.

Further, the rubber roller 53 of the developing roller 34 is provided so that the upper and rear portions thereof are exposed from the developing chamber 27. The rubber roller 53 is in contact with the supply roller 33 from the upper rear side and is in contact with the photosensitive drum 20 from the lower front side. That is, the developing roller 34 is disposed on the rear upper side of the supply roller 33 and on the front lower side of the photosensitive drum 20. The axial center of the supply roller 33, the axial center of the developing roller 34, and the axial center of the photosensitive drum 20 are located on substantially the same straight line along the radial direction of the photosensitive drum 20.

Further, the developing roller 34 is disposed at a distance from the scorotron charger 22 in the circumferential direction of the photosensitive drum 20. Specifically, the developing roller 34 is a virtual line segment (not shown) connecting the shaft center of the photosensitive drum 20 and the charging wire 23, and a virtual line connecting the shaft center of the photosensitive drum 20 and the shaft center of the developing roller 34. The line segment (not shown) forms an angle of about 120 °. That is, the developing roller 34, the scorotron charger 22, and the transfer roller 21 are arranged at substantially equal intervals (about 120 °) in the circumferential direction of the photosensitive drum 20.

The upper end portion of the layer thickness regulating blade 35 is fixed to the rear end portion of the upper wall of the developing chamber 27, and the lower end portion thereof is in contact with the developing roller 34 from the front side.

The rear portion of the lower film 36 is fixed to the lower film attaching surface 32, and the front end thereof is in contact with the peripheral surface of the developing roller 34 above the developing roller facing surface 31.
(3-2) Scanner Unit The scanner unit 16 is disposed on the front side of the process cartridge 15 so as to face the photosensitive drum 20 with a space in the front-rear direction.

The scanner unit 16 emits a laser beam L toward the photosensitive drum 20 based on the image data to expose the peripheral surface of the photosensitive drum 20.

Specifically, the laser beam L is emitted backward from the scanner unit 16 to expose the peripheral surface at the front end portion of the photosensitive drum 20. That is, the exposure point at which the photosensitive drum 20 is exposed (the peripheral surface at the front end of the photosensitive drum 20) is opposite to the nip portion 46 where the photosensitive drum 20 and the transfer roller 21 are in contact with the axial center of the photosensitive drum 20. Is set to the side.

At this time, the developing cartridge 19 is arranged below the emission locus of the laser beam L, and the scorotron charger 22 is arranged above the emission locus of the laser beam L.

A guide portion 37 for guiding the attachment / detachment of the process cartridge 15 is provided on the inner side surface of the main body casing 2 between the scanner unit 16 and the photosensitive drum 20. When the process cartridge 15 is detached from the main casing 2, the process cartridge 15 is guided by the guide portion 37, so that the developing cartridge 19 attached to the drum cartridge 18 has a lower emission locus of the laser beam L. Pass from the top to the top.

At this time, the various rollers (transfer roller 21, supply roller 33 and developing roller 34) provided in the process cartridge 15 also pass the emission locus of the laser beam L from the lower side to the upper side.
(3-3) Fixing Unit The fixing unit 17 is disposed above the rear portion of the drum cartridge 18. Specifically, the fixing unit 17 includes a heating roller 38 disposed above the scorotron charger 22 and a pressure roller 39 pressed against the heating roller 38 from the rear upper side.

That is, the heating roller 38 is disposed in the vicinity of the upper end portion (open end portion) of the grid 24 of the scorotron charger 22.
(4) Image Forming Operation The toner in the toner storage chamber 26 of the developing cartridge 19 is supplied to the supply roller 33 through the communication port 28 by the rotation of the agitator 29, and further supplied to the developing roller 34. Between 33 and the developing roller 34, it is triboelectrically charged to the positive polarity.

The toner supplied to the developing roller 34 is regulated by the layer thickness regulating blade 35 as the developing roller 34 rotates, and is carried on the surface of the developing roller 34 as a thin layer having a constant thickness.

On the other hand, the surface of the photosensitive drum 20 is uniformly charged by corona discharge of the charging wire 23 of the scorotron charger 22 and then exposed by the scanner unit 16. Thereby, an electrostatic latent image based on the image data is formed on the peripheral surface of the photosensitive drum 20. The toner carried on the developing roller 34 is supplied to the electrostatic latent image on the circumferential surface of the photosensitive drum 20, so that a toner image (developer image) is carried on the circumferential surface of the photosensitive drum 20.

The sheets S stacked on the sheet loading unit 9 are sent between the sheet feeding roller 12 and the sheet feeding pad 13 by the rotation of the pickup roller 11 and are turned one by one by the rotation of the sheet feeding roller 12. Thereafter, the paper S that has been squeezed is conveyed to the paper feed path 14 by the rotation of the paper feed roller 12 and is imaged one by one at a predetermined timing (between the photosensitive drum 20 and the transfer roller 21). Paper is fed to

Then, the sheet S is conveyed between the photosensitive drum 20 and the transfer roller 21 from the lower side to the upper side. At this time, the toner image is transferred onto the paper S to form an image.

The sheet S is heated and pressed when it passes between the heating roller 38 and the pressure roller 39. At this time, the image is thermally fixed on the paper S.

Thereafter, the paper S is conveyed toward the paper discharge roller 40 and is discharged onto the paper discharge tray 41 of the main casing 2 by the paper discharge roller 40.

In this way, the sheet S is fed from the sheet placing portion 9 and passes through the nip portion 46 as an example of the facing portion between the photosensitive drum 20 and the transfer roller 21, and then the heating roller 38 and the pressure roller Then, the paper is transported through a substantially C-shaped transport path as viewed from the side so that the paper is discharged onto the paper discharge tray 41.
2. Process Cartridge As shown in FIG. 2, the process cartridge 15 includes a drum cartridge 18 that is detachably attached to the main body casing 2 (see FIG. 1), and a developing cartridge 19 that is detachably attached to the drum cartridge 18. ing.

In the following description of the process cartridge 15, when referring to the direction, the side on which the photosensitive drum 20 is disposed is the rear side of the drum cartridge 18, and the side on which the scorotron charger 22 is disposed is the upper side. . That is, the up / down / front / rear direction with respect to the process cartridge 15 is slightly different from the up / down / front / rear direction with respect to the printer 1, and the process cartridge 15 is arranged such that the rear side is the rear upper side of the printer 1 and the front side is It is attached to.
(1) Drum Cartridge As shown in FIG. 5, the drum cartridge 18 includes a drum frame 57 as an example of a housing.

The drum frame 57 includes a base frame 58 as an example of a second frame and a cover frame 59 as an example of a first frame.
(1-1) Base Frame The base frame 58 is formed in a substantially bottomed frame shape having a substantially rectangular shape in plan view with the upper side open.

The base frame 58 includes a pair of side walls 61, a bottom wall 62, a base transfer member support wall 63 as an example of a second transfer member support portion, and a front wall 64.

The pair of side walls 61 are arranged to face each other with a gap in the left-right direction, and are formed in a substantially flat plate shape that is long in the front-rear direction.

At the rear end portion of the left side wall 61, a fitting recess 67, a protruding wall 68, and an opposing wall 69 are formed.

The fitting recess 67 is cut out from the upper edge of the left side wall 61 toward the lower side, and has a notch that is substantially rectangular in a side view with the upper side opened.

The protruding wall 68 is formed in a substantially rectangular flat plate shape that protrudes upward from the front peripheral edge of the fitting recess 67. The protruding wall 68 is provided with a receiving portion 71.

The receiving portion 71 is formed in a substantially rectangular shape in a side view extending in the vertical direction so as to slightly bulge from the rear edge of the outer (left side) half to the rear side at the substantially vertical center of the protruding wall 68. (See also FIG. 2 (b)).

The facing wall 69 is provided on the rear side of the protruding wall 68. The facing wall 69 is formed in a substantially flat plate shape that extends upward from the inner peripheral surface of the fitting recess 67 to substantially the same height as the upper end edge of the protruding wall 68 on the inner side (right side) half of the left side wall 61. A drum shaft insertion hole 72 and a cleaner locking portion 73 are formed in the facing wall 69.

The drum shaft insertion hole 72 is disposed in the center of the opposing wall 69 in the front-rear direction and is formed in a substantially circular shape when viewed from the side. The inner diameter of the drum shaft insertion hole 72 is formed to be substantially the same as the outer diameter of the drum shaft 122 (described later) of the photosensitive drum 20.

The cleaner locking portion 73 is formed in a substantially rectangular flat plate shape in side view extending upward from the upper end portion of the opposing wall 69. A cleaner locking hole 74 is formed at the upper end of the cleaner locking portion 73.

The cleaner locking hole 74 is formed in a substantially rectangular shape in side view extending in the front-rear direction.

As shown in FIG. 4, an opposing wall 75 and a protruding wall 76 are formed at the rear end of the right side wall 61.

The opposing wall 75 is formed in a substantially flat plate shape extending upward from the upper edge of the right side wall 61. The upper end edge of the facing wall 75 is formed in a substantially arc shape along the peripheral surface of the photosensitive drum 20. A drum shaft insertion hole 77 is formed in the opposing wall 75.

The drum shaft insertion hole 77 is disposed at the approximate center of the opposing wall 75 in the front-rear direction so as to coincide with the drum shaft insertion hole 72 of the left side wall 61 when projected in the left-right direction, and is formed in a substantially circular shape when viewed from the side. Has been. The inner diameter of the drum shaft insertion hole 77 is formed to be approximately the same diameter as the drum shaft insertion hole 72 of the left side wall 61.

The protruding wall 76 is formed in a substantially flat plate shape having a substantially rectangular shape in a side view extending upward from the upper surface of the front portion of the opposing wall 75.

As shown in FIGS. 4 and 5, the bottom wall 62 is formed in a substantially flat plate shape that is long in the left-right direction so as to be installed between the lower ends of the side walls 61.

As shown in FIGS. 4 and 5, the base transfer member support wall 63 is disposed at a rear side of the rear end portion of the bottom wall 62 with an interval, and is laid between the rear end portions of the side walls 61.

The base transfer member support wall 63 is formed in a substantially partial cylindrical shape that bulges toward the rear lower side along the peripheral surface of the transfer roller 21 and extends in the left-right direction. The base transfer member support wall 63 is closed at both ends in the left-right direction and open toward the upper side and the front side. The base transfer member support wall 63 has a left end portion disposed on the right side of the left side wall 61, and a right end portion disposed on the left side of the right side wall 61.

Further, in the base transfer member support wall 63, a lip portion 78 is formed at the front end portion thereof, and a protrusion 79, a plurality of (three) fitting projections 80, and a locking recess portion are formed at the rear upper end portion thereof. 81 is formed.

The lip 78 is formed in a substantially flat plate shape that extends from the front end of the base transfer member support wall 63 and extends downward in the left-right direction.

The protrusion 79 is formed so as to protrude from the inner surface (front surface) of the rear upper end of the base transfer member support wall 63 toward the front side.

The plurality of fitting protrusions 80 are arranged in parallel at equal intervals in the left-right direction at approximately the center in the left-right direction of the base transfer member support wall 63. The fitting protrusion 80 is formed in a substantially rectangular shape in front view so as to protrude upward from the upper surface of the rear upper end of the base transfer member support wall 63.

The locking recess 81 is disposed substantially at the center in the left-right direction of the base transfer member support wall 63 so as to overlap with the fitting protrusion 80 disposed in the center in the front-rear direction, and is recessed from the rear surface of the base transfer member support wall 63 to the front side. It is formed in a rectangular shape when viewed from the back.

An opening region between the lip portion 78 of the base transfer member support wall 63 and the front end portion of the bottom wall 62 serves as a paper feed opening 48 as an example of a second opening that feeds the paper S to the nip portion 46. It is partitioned.

The front wall 64 is constructed between the front end portions of the side walls 61 and is formed so as to incline obliquely upward toward the front continuously from the front end portion of the bottom wall 62.

Further, the front wall 64 is provided with a plurality (two) of pressing members 83 (FIG. 5) on the rear surface thereof at intervals in the left-right direction.

The pressing member 83 always presses the developing cartridge 19 toward the photosensitive drum 20 in a state where the developing cartridge 19 is mounted on the drum cartridge 18 by a spring (not shown) that biases backward. Is provided.

Further, an extension 84 is provided on the front wall 64.

The extending portion 84 is formed in a substantially flat plate shape extending in the left-right direction (longitudinal direction), and is formed so as to extend forward and upward from the substantially central portion in the left-right direction at the upper end portion of the front wall 64. The extending portion 84 is integrally provided with a drum gripping portion 85.

The drum gripping portion 85 is provided so as to extend in the left-right direction at a substantially central portion in the left-right direction on the rear surface of the extending portion 84. The drum grip 85 is formed so as to bulge backward as it goes upward.

In the base frame 58, a portion between the side walls 61 is defined as a drum housing portion 86 for supporting the photosensitive drum 20 on the front side of the base transfer member support wall 63.

Further, a cartridge in which the developing cartridge 19 can be mounted in a portion of the base frame 58 that is in front of the drum housing portion 86 (part partitioned by the bottom wall 62, the front wall 64, and the front portions of the side walls 61). It is partitioned as a cartridge mounting portion 87 as an example of a storage portion.
(1-2) Cover Frame The cover frame 59 is disposed above the rear end portion of the base frame 58. The cover frame 59 is formed in a substantially rectangular tube shape that extends in the left-right direction and opens toward the lower side and the front side.

The cover frame 59 includes a pair of side walls 89, a charger support 90, a pair of end walls 91, and a cover transfer member support wall 92 as an example of a first transfer member support. .

The pair of side walls 89 are opposed to each other with an interval in the left-right direction, and are formed in a substantially flat plate shape extending in the up-down direction.

As shown in FIG. 5, a fitting convex portion 95 and a positioning portion 96 are formed on the left side wall 89.

The fitting convex portion 95 is formed in a substantially rectangular shape in a side view projecting downward from the lower end portion of the left side wall 89. The vertical length (projection length) of the fitting convex portion 95 is slightly shorter than the vertical length (depth) of the fitting concave portion 67 of the left side wall 61 of the base frame 58. In addition, the front-rear direction length of the fitting convex portion 95 is slightly shorter than the front-rear direction length of the fitting concave portion 67 of the left side wall 61 of the base frame 58. In addition, a drum shaft insertion hole 97 is formed in the fitting convex portion 95.

The drum shaft insertion hole 97 is formed in a substantially circular shape in a side view at the center in the front-rear direction of the fitting convex portion 95. The inner diameter of the drum shaft insertion hole 97 is formed to be substantially the same as the outer diameter of the drum shaft 122 (described later) of the photosensitive drum 20.

The positioning portion 96 is formed in a substantially rectangular shape in a side view extending in the vertical direction so as to slightly bulge from the front end edge toward the front side at a substantially vertical center of the left side wall 89 (FIG. 2 ( See also b)). Further, the vertical length of the positioning portion 96 is shorter than the vertical length of the receiving portion 71 of the left side wall 61 of the base frame 58.

As shown in FIG. 4, a fitting convex portion 98 is formed on the right side wall 89.

The fitting convex part 98 is formed in a substantially semicircular shape in a side view projecting downward from the lower end part of the right side wall 89. A drum shaft insertion hole 99 is formed in the fitting convex portion 98.

The drum shaft insertion hole 99 is formed in a substantially circular shape in side view so as to coincide with the drum shaft insertion hole 97 of the left sidewall 89 when projected in the left-right direction. ing. The inner diameter of the drum shaft insertion hole 99 is substantially the same as the inner diameter of the drum shaft insertion hole 97 of the right side wall 89.

As shown in FIG. 5, the charger support portion 90 is formed in a substantially U-shaped cross section that extends in the left-right direction and is opened downward so as to be installed between the upper ends of both side walls 89. (See FIG. 4). The above-described scorotron charger 22 is supported on the charger support portion 90. The charger support portion 90 is formed with a ventilation opening 100 and a cleaner locking portion insertion hole 101 (see FIG. 6).

The ventilation opening 100 is formed in a substantially straight slit shape extending in the left-right direction along the charging wire 23 of the scorotron charger 22 at the upper end portion of the charger support 90.

The cleaner engaging portion insertion hole 101 is formed at the left end portion of the charger support portion 90 at the boundary portion with the left side wall 89. The cleaner engagement portion insertion hole 101 is formed in a substantially rectangular shape in a plan view that is long in the front-rear direction so as to penetrate the charger support portion 90 in the vertical direction.

Further, as shown in FIG. 6, the charger support portion 90 is formed with a protrusion 102 and a reinforcing plate 103 as an example of a plate-like member.

The protrusion 102 is formed in a substantially prismatic shape protruding from the front surface of the upper portion of the left end portion of the charger support portion 90 toward the front side.

The reinforcing plate 103 is formed in a substantially rectangular flat plate shape in plan view that extends from the substantially vertical center of the front surface of the charger support portion 90 in the horizontal direction along the charging wire 23 and extends toward the front side. ing. The reinforcing plate 103 includes a standing portion 104.

The standing portion 104 is formed in a substantially flat plate shape in front view that protrudes upward from the upper surface in the front-rear direction substantially center of the left end portion of the reinforcing plate 103.

As shown in FIG. 5, the pair of end walls 91 has a substantially rectangular shape in plan view that connects both the left and right ends of the rear end edge of the pair of side walls 89 and the rear end edge of the charger support 90. It is formed in a substantially flat plate shape.

The cover transfer member support wall 92 is disposed at a distance from the rear end portion of the charger support portion 90 and is formed in a substantially flat plate shape having a substantially rectangular shape in plan view and extending between the lower end portions of the both end walls 91.

Also, an extended portion 107, a plurality of (three) fitting holes 108, and a locking claw 109 are formed at the rear end portion of the cover transfer member support wall 92.

The extended portion 107 is formed as a protrusion that protrudes downward from the rear edge of the cover transfer member support wall 92 and extends in the left-right direction.

The plurality of fitting holes 108 are arranged in parallel at equal intervals in the left-right direction at approximately the center in the left-right direction of the cover transfer member support wall 92. The fitting hole 108 is formed in a substantially rectangular shape in plan view.

The locking claw 109 is arranged at the approximate center in the left-right direction of the cover transfer member support wall 92 so as to overlap the fitting hole 108 arranged in the center in the front-rear direction, and downward from the lower surface of the cover transfer member support wall 92. It protrudes and is formed in a substantially bowl shape that bends forward at its tip (lower end) (see FIG. 4).

The outer dimensions in the vertical direction and the left-right direction of the tip (bent portion) of the locking claw 109 are shorter than the vertical dimensions in the vertical direction and the left-right direction of the locking recess 81 (see FIG. 2A). ).

An opening area between the charger support section 90, the pair of end walls 91, and the cover transfer member support wall 92 is a discharge as an example of a first opening through which the sheet S is discharged from the nip portion 46. A paper opening 49 is defined.

That is, the paper discharge opening 49 is defined in the cover frame 59 and is defined upstream of the charger support portion 90 in the rotation direction of the photosensitive drum 20 (clockwise as viewed from the left side).
(1-3) Scorotron Charger and Photosensitive Drum As described above, the scorotron charger 22 and the photosensitive drum 20 are supported on the drum cartridge 18.

The scorotron charger 22 includes the above-described charging wire 23 and grid 24 and a wire cleaner 112.

The wire cleaner 112 is supported at the upper end of the charger support 90 so as to be slidable in the left-right direction. As shown in FIG. 6, the wire cleaner 112 is formed in a substantially L shape in a side view that is long in the left-right direction. Specifically, the wire cleaner 112 includes a horizontal portion 113 that extends in the front-rear direction and a vertical portion 114 that extends downward from the front end of the horizontal portion.

The horizontal portion 113 includes a cleaning unit 115 (see FIG. 2A) and a locking projection 116.

The cleaning unit 115 is disposed in the grid 24 through the ventilation opening 100 (see FIG. 2A). The cleaning unit 115 sandwiches the charging wire 23 via a cleaning member 117 such as sponge or non-woven fabric (see FIG. 2A), and is provided so as to be movable in the left-right direction along the charging wire 23.

The locking projection 116 is formed in a substantially prismatic shape protruding from the left surface of the horizontal portion 113 to the left side. The vertical dimension and the longitudinal dimension of the locking projection 116 are shorter than the vertical dimension and the longitudinal dimension of the cleaner locking hole 74 of the base frame 58.

The vertical portion 114 includes a cleaner grip 118 as an example of a grip that is gripped when the wire cleaner 112 is moved.

The cleaner gripping portion 118 extends from the front surface of the vertical portion 114 at the approximate center in the left-right direction toward the front side. That is, the cleaner gripping portion 118 protrudes to the front side, that is, orthogonal to the direction (vertical direction) along the straight line R passing through the axial center of the photosensitive drum 20 and the charging wire 23 when projected in the left-right direction. It protrudes in the direction (front-rear direction) (see FIG. 2A). A rear lower end portion of the cleaner gripping portion 118 is cut out in a substantially rectangular shape in a side view.

The photosensitive drum 20 includes a drum main body 120 and a drum shaft 122 as shown in FIG.

The drum body 120 is disposed between the facing wall 75 of the left side wall 61 and the facing wall 69 of the right side wall 61 on the front side of the transfer roller 21. The drum body 120 is formed in a substantially cylindrical shape extending in the left-right direction. Specifically, the drum main body 120 includes a metal base tube formed in a substantially cylindrical shape extending in the left-right direction, and a resin photosensitive layer covering the surface of the base tube.

As shown in FIG. 2A, the drum shaft 122 is inserted into the drum main body 120 along the central axis of the photosensitive drum 20. The drum shaft 122 is made of metal and has a substantially cylindrical shape extending in the left-right direction. The drum shaft 122 is formed longer in the left-right direction than the drum main body 120. The left end portion of the drum shaft 122 is rotatably inserted into the drum shaft insertion hole 72 of the left side wall 61 of the base frame 58 and the drum shaft insertion hole 97 of the left side wall 89 of the cover frame 59. The right end of the drum shaft 122 is rotatably inserted into the drum shaft insertion hole 77 of the right side wall 61 of the base frame 58 and the drum shaft insertion hole 99 of the right side wall 89 of the cover frame 59.
(1-4) Assembling the Drum Cartridge To assemble the drum cartridge 18, as shown in FIG. 5, first, the transfer roller 21 is rotatably assembled to the base transfer member support wall 63 of the base frame 58, and as described above. The drum main body 120 is disposed in the drum housing portion 86.

On the other hand, as shown in FIG. 6, the wire cleaner 112 is inserted into the ventilation opening 100 from the left side of the charger support portion 90 and the lower surface of the cleaner gripping portion 118 is connected to the upper surface of the reinforcing plate 103. Assemble so as to face each other.

Thus, the reinforcing plate 103 is disposed so as to protrude forward from the cleaner gripping portion 118.

Next, as shown in FIG. 5, a cover frame 59 is combined from above so that the rear end portion of the base frame 58 covers the transfer roller 21 and the photosensitive drum 20.

Specifically, first, the front end (lower end) of the locking claw 109 of the cover frame 59 is fitted into the locking recess 81 of the base frame 58, and the extended portion 107 of the cover frame 59 is connected to the base of the base frame 58. The transfer member support wall 63 is brought into contact with the upper surface of the rear end portion.

At this time, the tip (lower end) of the locking claw 109 of the cover frame 59 is fitted into the locking recess 81 of the base frame 58 (see FIG. 2A).

After that, as shown in FIG. 4, the fitting convex portion 98 of the right side wall 89 of the cover frame 59 is brought into contact with the right wall of the opposing wall 75 of the right side wall 61 of the base frame 58 and as shown in FIG. 5. Then, the fitting convex portion 95 of the left side wall 89 of the cover frame 59 is fitted into the fitting concave portion 67 of the left side wall 61 of the base frame 58. At this time, the wire cleaner 112 is disposed in the middle of the cover frame 59 in the left-right direction.

Then, the fitting protrusions 80 of the base frame 58 are loosely fitted into the corresponding fitting holes 108 of the cover frame 59, respectively. Further, the cleaner locking portion 73 of the base frame 58 is inserted into the cleaner locking portion insertion hole 101 of the cover frame 59. The upper end portion of the cleaner locking portion 73 inserted into the cleaner locking portion insertion hole 101 protrudes above the wire cleaner 112 assembled to the charger support portion 90.

Also, the drum shaft insertion hole 97 in the left side wall 89 of the cover frame 59 is opposed to the drum shaft insertion hole 72 in the left side wall 61 of the base frame 58. The drum shaft insertion hole 99 in the right side wall 89 of the cover frame 59 is opposed to the drum shaft insertion hole 77 in the right side wall 61 of the base frame 58.

Further, the positioning portion 96 of the left side wall 89 of the cover frame 59 is disposed opposite to the rear side of the receiving portion 71 of the left side wall 61 of the base frame 58 (see FIG. 2B).

After that, the wire cleaner 112 is disposed at the left end portion of the cover frame 59 so that the locking protrusion 116 of the wire cleaner 112 is locked in the cleaner locking hole 74 of the cleaner locking portion 73, and the cleaner gripping portion. The standing portion 104 is slidably disposed in the notch at the rear lower end portion of the 118, and the wire cleaner 112 is disposed at the standby position. In other words, the cleaner grip 118 is disposed on the front side with respect to the scorotron charger 22.

Then, the cleaning member 117 is moved by the cleaning member 117 by gripping the cleaner gripping portion 118 of the wire cleaner 112 disposed at the standby position and moving the wire cleaner 112 along the charging wire 23 over the entire left and right direction of the charging wire 23. 23 is cleaned. After cleaning the charging wire 23, the wire cleaner 112 is again placed at the standby position.

Next, the drum shaft 122 is inserted into the drum main body 120 through the drum shaft insertion holes (72, 77, 97, 99) of the base frame 58 and the cover frame 59.

Then, the photosensitive drum 20 is rotatably supported by the base frame 58 and the cover frame 59 at both left and right ends of the drum shaft 122. Further, the base frame 58 and the cover frame 59 are integrally connected via a drum shaft 122.

Thus, the assembly of the drum cartridge 18 is completed.

At this time, the free end portion (front end portion) of the reinforcing plate 103 is disposed at a position protruding forward from the charger support portion 90 relative to the photosensitive drum 20 when projected in the vertical direction.

Also, the base transfer member support wall 63 and the cover transfer member support wall 92 are combined to form an example of a transfer member support portion, and the transfer roller 21 is rotatably supported inside thereof.

In the assembled drum cartridge 18, the right side wall of the drum frame 57 is combined with the side wall 61 of the base frame 58 and the side wall 89 of the cover frame 59, so that a guide rail 125 is defined. As shown in FIG. 2B, a guide rail 125 is defined on the side wall 61 of the base frame 58 on the left side wall of 57.

The guide rail 125 includes a guide surface 126, a guide groove 127, and a vertical portion 128.

The guide surface 126 is formed at the upper end portion of the front side portion of the side wall 61 so as to be inclined downward toward the rear side.

The guide groove 127 is formed in a substantially C shape in a side view in which a front side is opened and a front side is notched toward the rear side under a portion connected to the side wall 89 in the rear side portion of the side wall 61. The groove width (vertical length) of the guide groove 127 is formed to be substantially the same length (slightly longer) as the outer diameter of the collar 137 (described later). The guide groove 127 is formed with a substantially rectangular protruding portion 129 that protrudes rearward and downward from the front end portion on the upper side thereof, and the lower surface thereof is continuous with the guide surface 126.

The front end surface of the rear portion of the side wall of the drum cartridge 18 is partitioned as a vertical portion 128 extending in the vertical direction.

The lower end portion of the vertical portion 128 is continuous with the upper end portion of the protruding portion 129 of the guide groove 127.
(2) Developing Cartridge The developing cartridge 19 is disposed on the right side of the developing frame 25 and is provided on the left side of the developing frame 25 with a power supply unit (not shown) to which electric power is input from the outside. And a gear cover 133 (see FIGS. 2B and 3B) that covers the gear train (not shown).

The gear cover 133 is formed in a substantially box shape that opens to the right and rear. The gear cover 133 is provided with a claw-shaped portion 134.

The claw-shaped part 134 is formed in a substantially claw shape in a side view extending in the front upper direction and the rear lower direction, and is formed in a substantially columnar shape protruding leftward from the left upper surface of the gear cover 133.

A curved surface 135 is defined at the rear end portion of the claw-shaped portion 134.

The curved surface 135 is partitioned into a substantially arc shape that curves downward from the upper side surface continuously toward the rear side at the rear end portion of the claw-shaped portion 134.

It should be noted that the curved surface 135 is also provided in a symmetrical shape and arrangement in a power supply unit (not shown) on the right side of the developing frame 25.

On the other hand, a substantially cylindrical collar 137 is fitted on both ends of the developing roller shaft 52.

The gear cover 133 covers the gear train (not shown), and is fixed to the left side wall of the developing frame 25 so that the collar 137 is exposed to the left of the developing cartridge 19 from the rear end. .

In the state in which the gear cover 133 is fixed to the developing frame 25, the rear side portion is defined as a contact portion 140 that protrudes upward from the developing frame 25.

Further, the developing grip 25 is provided on the developing frame 25 of the developing cartridge 19.

The development gripping portions 138 are formed in a substantially flat plate shape having a substantially rectangular shape when viewed from the front, and are provided at both ends in the left-right direction on the front surface of the development frame 25. Further, the development gripping portion 138 is formed to extend obliquely upward as it continues forward from the upper end portion of the front surface of the development frame 25.
3. As shown in FIG. 2A, the developing cartridge 19 is mounted on the cartridge mounting portion 87 of the drum cartridge 18 by the urging force of the pressing member 83 (see FIG. 5). Then, it is pressed upward toward the photosensitive drum 20.

At this time, as shown in FIG. 2B, the collar 137 of the developing cartridge 19 is fitted in the guide groove 127 of the drum cartridge 18. That is, the rubber roller 53 of the developing roller 34 is pressed against the drum body 120 of the photosensitive drum 20 from the front side by the collar 137 being guided toward the photosensitive drum 20 by the guide groove 127.

At this time, the upper end portion of the development gripping portion 138 is disposed below the upper end portion of the drum gripping portion 85.
4). Detachment of Developer Cartridge from Drum Cartridge In order to detach developer cartridge 19 from drum cartridge 18, developer cartridge 138 of developer cartridge 19 is grasped, and developer cartridge 19 is detached in the direction Y (left side) with collar 137 as a fulcrum. Rotate toward the rear upper side along the substantially counterclockwise direction).

At this time, the separation of the rear end portion of the developing cartridge 19 is controlled by the contact between the upper end portion of the collar 137 and the lower end portion of the protruding portion 129 of the guide groove 127.

When the developing cartridge 19 is further rotated, as shown in FIG. 3, the curved surface 135 of the claw-shaped portion 134 comes into contact with the vertical portion 128 and the collar 137 is detached from the guide groove 127, so that the guide surface It is guided forward and upward along 126.

At this time, the contact portion 140 of the gear cover 133 of the developing cartridge 19 contacts the free end portion (front end portion) of the reinforcing plate 103 of the drum cartridge 18.

Further, when the developing cartridge 19 is rotated along the separation direction Y with the contact portion between the curved surface 135 and the vertical portion 128 as a fulcrum, the developing cartridge 19 is detached from the drum cartridge 18 upward.

Thus, the separation of the developing cartridge 19 from the cartridge mounting portion 87 is completed.

In order to attach the developing cartridge 19 to the drum cartridge 18, the developing cartridge 19 and the drum cartridge 18 are operated in reverse to the above-described detachment operation.

Specifically, the rear end portion of the developing cartridge 19 is inserted into the rear end portion of the cartridge mounting portion 87 of the drum cartridge 18 from above.

Then, the collar 137 contacts the guide surface 126 and the curved surface 135 of the claw-shaped portion 134 contacts the vertical portion 128.

Next, it is rotated in the mounting direction X (substantially clockwise in the left side view) with the contact portion between the curved surface 135 and the vertical portion 128 as a fulcrum. Then, the collar 137 moves rearward and downward along the guide surface 126, and the front end portion of the developing cartridge 19 is moved to the front lower side. Then, when further rotated in the mounting direction X, the collar 137 is moved rearward and upward along the guide groove 127 and inserted into the guide groove 127, and as shown in FIG. The front end portion is accommodated in the front end portion of the cartridge mounting portion 87. Thus, the guide groove 127 guides the collar 137 in order to attach and detach the developing cartridge 19 to and from the drum cartridge 18.

Thus, the mounting of the developing cartridge 19 to the cartridge mounting portion 87 is completed.

In other words, the developing cartridge 19 is attached to and detached from the cartridge mounting portion 87 of the drum cartridge 18 while being rotated.
5. Mounting of Process Cartridge on Main Body Casing To mount the process cartridge 15 on the main body casing 2, first, as shown in FIG. 1 and described above, the top cover 7 of the main body casing 2 is placed in the open position.

Next, the drum grip 85 of the process cartridge 15 is gripped, and the process cartridge 15 is inserted into the main casing 2 through the cartridge opening 5.

Then, when the process cartridge 15 is pushed downward along the guide portion 37, the process cartridge 15 is inserted into the main body casing 2.

At this time, since the upper end portion of the cleaner locking portion 73 protrudes upward from the wire cleaner 112, when the process cartridge 15 is inserted into the main body casing 2, the wire cleaner 112 is separated from the members in the main body casing 2. Interference can be prevented.

Thus, the mounting of the process cartridge 15 on the main casing 2 is completed.

At this time, the cleaner gripping portion 118 is disposed on the front side with respect to the scorotron charger 22, and therefore, when the top cover 7 is opened in a state where the process cartridge 15 is mounted on the main body casing 2, the cleaner gripping portion 118 is brought to the standby position. The cleaner gripping part 118 of a certain wire cleaner 112 can be gripped, and the charging wire 23 can be cleaned.
6). Air Flow Inside the Printer During image formation, as shown in FIG. 1, the sheet S is heated and pressurized as it passes between the heating roller 38 and the pressure roller 39 of the fixing unit 17 as described above. And the image is heat-fixed.

Therefore, in the printer 1, the air flow A 1 toward the heating roller 38 is generated by the heat generated by the heating roller 38. Specifically, the air flow A 1 passes between the rear lower end portion of the scanner unit 16 and the upper end portion of the front wall 64 of the process cartridge 15 from the opened paper opening 6. The airflow A1 flows from the front side to the rear side (in the order of the front wall 64, the developing cartridge 19, and the charger support unit 90) above the process cartridge 15, and is on the upper side in the vicinity of the paper feed opening 48 of the process cartridge 15. And passes between the heating roller 38 and the pressure roller 39 of the fixing unit 17, and is discharged from the discharge roller 40 to the outside of the printer 1.

Further, in the process cartridge 15, when the scorotron charger 22 charges the surface of the photosensitive drum 20, an air flow A 2 that flows from the scorotron charger 22 toward the photosensitive drum 20 is generated by the discharge of the charging wire 23. . Specifically, the air flow A 2 is sucked from the ventilation opening 100, travels toward the photosensitive drum 20 through the grid 24, and hits the surface of the photosensitive drum 20, thereby scattering transfer residual toner attached to the photosensitive drum 20. The airflow A2 that hits the surface of the photosensitive drum 20 is separated into an airflow A3 that goes to the downstream side (rear side) in the rotation direction of the photosensitive drum 20 and an airflow A4 that goes to the upstream side (front side).

The airflow A3 is discharged from the process cartridge 15 to the fixing unit 17 through the paper feed opening 48 and discharged to the outside of the printer 1 together with the airflow A1.

The airflow A4 is generated from the process cartridge 15 to the front end portion of the charger support portion 90 (specifically, the front end portion of the reinforcing plate 103) and the rear upper end portion of the developing cartridge 19 while entraining toner in the atmosphere around the developing roller 34. And the airflow A1 flowing above the process cartridge 15 is joined. The airflow A4 flows together with the airflow A1 above the charger support portion 90 from the front side toward the rear side, and part of the merged airflow (airflow A1 and airflow A4) is discharged to the outside of the printer 1. On the other hand, the remainder of the combined airflow (airflow A1 and airflow A4) is again sucked into the scorotron charger 22 from the ventilation opening 100 and becomes airflow A2 toward the photosensitive drum 20.
7). Operation and Effect (1) According to the drum cartridge 18, as shown in FIG. 5, the drum frame 57 is disposed adjacent to the charger support portion 90 in the drum frame 57. Can be planned.

On the other hand, when the size of the drum frame 57 is reduced, the strength of the charger support portion 90 is reduced. However, according to the drum cartridge 18, the cleaner holding portion 118 protruding to the front side is held and the charging wire 23 is attached. The cleaning member 117 can be moved along.

That is, since the force for gripping the cleaner gripping portion 118 and moving the cleaning member 117 acts along the charging wire 23, the charging wire 23 can be cleaned without directly applying a load to the charger support portion 90. .

Further, even when a force is applied to the rear side from the cleaner gripping portion 118 to the charger support portion 90 during cleaning, the direction thereof is the vertical direction (the straight line R passing through the photosensitive drum 20 and the charging wire 23). Therefore, the relative arrangement of the scorotron charger 22 and the photosensitive drum 20 in the vertical direction can be prevented from changing.

As a result, the charging wire 23 can be cleaned while suppressing the relative arrangement of the scorotron charger 22 and the photosensitive drum 20 from being changed.
(2) Further, according to the drum cartridge 18, as shown in FIG. 5, the paper discharge opening 49 is formed in the cover frame 59 of the drum frame 57.

Therefore, the position of the paper discharge opening 49 can be stabilized by combining the cover frame 59 and the base frame 58 as compared with the case where the paper discharge opening 49 is formed.
(3) Also, according to the drum cartridge 18, as shown in FIG. 4, the cover frame 59 includes the charger support portion 90 and the cover transfer member support wall 92, and the base frame 58 includes the base transfer member. A support wall 63 is provided.

Therefore, the transfer member support portion can be formed from the cover transfer member support wall 92 and the base transfer member support wall 63 with a simple configuration in which the cover frame 59 and the base frame 58 are combined.
(4) Further, according to the drum cartridge 18, as shown in FIG. 5, the charger support portion 90 includes the reinforcing plate 103 formed over the axial direction of the charging wire 23. The rigidity of 90 can be improved.

Therefore, even when a load acts on the charger support portion 90 when cleaning the charging wire 23, the rigidity of the charger support portion 90 can be maintained.

As a result, the charging wire 23 can be cleaned while the relative arrangement of the scorotron charger 22 and the photosensitive drum 20 is reliably maintained.
(5) Further, according to the drum cartridge 18, the reinforcing plate 103 that protrudes forward from the charger support portion 90 relative to the cleaner gripping portion 118, rather than the cleaner gripping portion 118, as shown in FIG. Since it is arranged on the photosensitive drum 20 side, it is possible to prevent the cleaner gripping portion 118 and the photosensitive drum 20 from contacting each other.

Therefore, when the user grips the cleaner grip 118, the charging wire 23 can be cleaned by gripping the cleaner grip 118 without touching the photosensitive drum 20.
(6) According to the drum cartridge 18, as shown in FIG. 2A, the front end portion (free end portion) of the reinforcing plate 103 is more forward than the photosensitive drum 20 from the charger support portion 90. Since it is arranged at the protruding position, it is possible to shield light from the cleaner gripping portion 118 side in the vertical direction.

Therefore, the quality of the photosensitive drum 20 can be maintained.
(7) Further, according to the drum cartridge 18, as shown in FIG. 2A, paper is fed between the bottom wall 62 and the base transfer member support wall 63 formed integrally with the base frame 58. Since the opening 48 is formed, the accuracy of the relative arrangement of the paper feed opening 48 with respect to the nip portion 46 can be easily ensured.

Therefore, the paper S can be reliably passed through the paper feed opening 48 and supplied to the nip portion 46.
(8) According to this process cartridge 15, when the contact portion 140 of the gear cover 133 of the developing cartridge 19 is detached from the cartridge mounting portion 87, as shown in FIG. It abuts against the end.

Therefore, the cleaner gripping portion 118 can be protected by the reinforcing plate 103 when the developing cartridge 19 is detached.

As a result, it is possible to suppress the load from acting on the charging wire 23 and the grid 24 that are cleaned by holding the cleaner holding portion 118 and moving the cleaning member 117.
(9) According to the printer 1, as shown in FIG. 1, an air flow A 1 is generated toward the fixing unit 17 due to heat generation of the fixing unit 17.

In this case, when charging the surface of the photosensitive drum 20, the airflow A 2 generated from the scorotron charger 22 toward the photosensitive drum 20 strikes the surface of the photosensitive drum 20, thereby scattering the toner attached to the photosensitive drum 20. In this way, the air current A3 is directed to the downstream side (rear side) in the rotation direction of the photosensitive drum 20, and the air current A4 is directed to the upstream side (front side).

Then, the airflow A4 directed to the front side is returned to the vicinity of the scorotron charger 22 again on the airflow A1 flowing above the charger support portion 90 while the toner in the atmosphere around the developing roller 34 is involved.

However, since the reinforcing plate 103 is formed on the charger support portion 90, the airflow A4 is guided away from the charger 22. As a result, the airflow A4 can be reduced from entering the charger 22 together with the scattered toner.

As a result, the scattered toner can be prevented from entering the scorotron charger 22.
(10) Also, according to the printer 1, as shown in FIG. 1, the scorotron charger 22, the developing roller 34, and the transfer roller 21 are arranged substantially equally around the photosensitive drum 20. A series of operations in which the surface of the photosensitive drum 20 is charged by the scorotron charger 22, a toner image is formed on the surface of the photosensitive drum 20 by the developing roller 34, and the toner image is transferred onto the paper S together with the transfer roller 21 with a good balance. It can be carried out stably.
8). Second Embodiment With reference to FIG. 7, a process cartridge 15 according to a printer 1 of a second embodiment of the image forming apparatus will be described. In the second embodiment, members similar to those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

In the first embodiment described above, the reinforcing plate 103 is disposed so as to protrude forward from the cleaner gripping portion 118.

On the other hand, in the second embodiment of the present invention, as shown in FIG. 7, the cleaner gripping portion 118 may have a shape protruding forward from the reinforcing plate 103. That is, when the wire cleaner 112 is not positioned at the standby position but at any position in the left-right direction along the charging wire 23, the cleaner gripping portion 118 is brought into contact with the developing cartridge 19. May be projected so as to intersect with the attachment / detachment locus of the developing cartridge 19 (specifically, the attachment / detachment locus T of the rear end portion of the layer thickness regulating blade 35).

Thus, when the wire cleaner 112 is not in the standby position, the layer thickness regulating blade 35 of the developing cartridge 19 and the cleaner gripping portion 118 interfere when the developing cartridge 19 is mounted.

For this reason, the cleaner grip 118 prevents the developer cartridge 19 from being attached to the drum cartridge 18, so the user must place the wire cleaner 112 in the standby position and then attach the developer cartridge 19 to the drum cartridge 18. Can do.
9. Other Embodiments The printer 1 described above is an embodiment of the image forming apparatus of the present invention, and the present invention is not limited to the above-described embodiment.

The image forming apparatus of the present invention can be configured as a color printer in addition to the above-described monochrome printer.

When the image forming apparatus is configured as a color printer, the image forming apparatus includes a direct tandem type color printer including a plurality of photosensitive members and a recording medium conveying member, a plurality of photosensitive members, an intermediate transfer member, and a transfer member. It can be configured as an intermediate transfer type tandem color printer.

Further, the process cartridge 15 of the present invention is configured as an integrated type integrally including the drum cartridge 18 and the developing cartridge 19 in addition to the separation type in which the drum cartridge 18 and the developing cartridge 19 are separated as described above. You can also.

Furthermore, the photosensitive drum 20 can be provided in the main casing 2 and only the developing cartridge 19 can be attached to and detached from the main casing 2.

Further, the developing cartridge 19 can be configured such that a toner cartridge that contains toner is detachably attached to a frame having the developing roller 34.

Further, in place of the above-described photosensitive drum 20, for example, a photosensitive member such as a photosensitive belt can be applied.

Further, instead of the developing roller 34 described above, for example, a developer carrier such as a developing sleeve, a developing belt, or a brush-like roller can be applied.

Further, instead of the above-described supply roller 33, for example, a supply member such as a supply sleeve, a supply belt, or a brush-like roller can be applied.

Further, instead of the agitator 29 described above, for example, a conveying member such as an auger screw or a conveying belt can be applied.

Further, instead of the transfer roller 21 described above, for example, a contact type transfer member such as a transfer belt, a transfer brush, a transfer blade, or a film type transfer device, or a non-contact type transfer member such as a corotron type is used. It can also be applied.

Further, instead of the above scorotron charger 22, for example, a non-contact charger such as a corotron charger, a sawtooth discharge member, or a contact charger such as a charging roller may be applied. it can.

Further, instead of the scanner unit 16 described above, an exposure member such as an LED unit can be applied.

Furthermore, the image forming apparatus of the present invention can also be configured as a multi-function machine equipped with an image reading unit and the like.

DESCRIPTION OF SYMBOLS 1 Printer 15 Process cartridge 17 Fixing unit 18 Drum cartridge 19 Developing cartridge 20 Photosensitive drum 21 Transfer roller 22 Scorotron type charger 23 Charging wire 34 Developing roller 46 Nip part 48 Paper feed opening 49 Paper discharge opening 57 Drum frame 58 Base frame 59 Cover Frame 62 Bottom wall 63 Base transfer member support wall 87 Cartridge mounting portion 90 Charger support portion 92 Cover transfer member support wall 103 Cleaner rail 117 Cleaning member 118 Cleaner gripping portion 140 Contact portion R Straight line

Claims

A housing (57);
A photoconductor (20) that is rotatable and configured to carry a developer image on its peripheral surface;
A transfer member (21) disposed opposite to the peripheral surface of the photoconductor (20) and configured to transfer the developer image from the peripheral surface of the photoconductor (20) to a recording medium;
A charger (22) disposed opposite to the circumferential surface of the photoconductor (20) at an interval and configured to charge the surface of the photoconductor (20);
The charger (22)
A charging wire (23) extending along the axial direction of the photoreceptor (20) and configured to charge the photoreceptor (20) by corona discharge;
A cleaning member (117) that is movable along the charging wire (23) while being rubbed against the charging wire (23), and for cleaning the charging wire (23);
A gripping portion (118) configured to grip when the cleaning member is moved,
The housing (57)
A transfer member support (63, 92) for rotatably supporting the transfer member;
A charger support (90) for supporting the charger;
It is formed between the charger support part (90) and the transfer member support part (63, 92), and is discharged from a facing part (46) where the photoconductor (20) and the transfer member (21) face each other. A first opening (49) for allowing the recording medium to pass through,
The first opening (49) is adjacent to the charger support (90) on the upstream side in the rotation direction of the photoconductor (20),
The gripping part (118) protrudes in a crossing direction intersecting a direction along a straight line passing through the axial center of the photoconductor (20) and the charging wire (23) when projected in the axial direction. A photosensitive member cartridge.
The housing (57)
A first frame (59) disposed on the charger side in a direction along the straight line with respect to the photoreceptor (20);
A second frame (58) disposed on the opposite side of the charger in the direction along the straight line with respect to the photoreceptor (20),
2. The photosensitive member cartridge according to claim 1, wherein the first opening (49) is formed in the first frame (59).
The first frame (59) includes the charger support (90) and a first transfer member support (92).
The second frame (58) includes a second transfer member support portion (63),
The transfer member support portion (63, 92) is formed by combining the first transfer member support portion (92) and the second transfer member support portion (63). 3. A photosensitive member cartridge according to 2.
The charger support section (90) includes a plate member (103) formed over the axial direction of the charging wire (23) so as to be able to face the grip section (118). The photosensitive member cartridge according to claim 1.
The plate-like member (103)
In the direction along the straight line, provided on the photoconductor (20) side with respect to the grip portion (118),
5. The photosensitive member cartridge according to claim 4, wherein, in the crossing direction, the photosensitive member cartridge protrudes from the charger support portion (90) rather than the grip portion (118).
The free end portion of the plate-like member (103) is disposed at a position protruding from the charger support portion (90) rather than the photoconductor (20) when projected in a direction along the straight line. The photosensitive member cartridge according to claim 5, wherein
The housing (57) further includes a bottom wall (62) formed on the opposite side of the charger (22) with respect to the photoreceptor (20),
The bottom wall (62) and the transfer member support portion (63) form a second opening (48) for allowing the recording medium supplied to the facing portion (46) to pass between them. The photoconductor cartridge according to claim 1, wherein
A process cartridge (15) comprising: the photosensitive member cartridge (18) according to claim 4; and a developing cartridge (19) that contains a developer and is configured to be detachable from the photosensitive member cartridge (18). ,
The photosensitive cartridge (18) includes a cartridge housing portion (87) configured to be attached and detached while the developing cartridge (19) is rotated.
The developing cartridge (19) includes an abutting portion (140) that abuts on the plate-like member (103) when the developing cartridge (19) is detached from the cartridge housing portion (87). Process cartridge.
An image forming apparatus (1) comprising the process cartridge (15) according to claim 8,
An image forming apparatus, wherein a fixing device (17) for fixing the developer image on the recording medium is disposed downstream of the process cartridge (15) in the conveyance direction of the recording medium.
The developer cartridge (19) includes a developer carrier (34) facing the photoconductor (20) in a state of being mounted in the cartridge housing portion (87).
The charger (22), the transfer member (21), and the developer carrier (34) are:
When projected in the axial direction,
A first imaginary line connecting the axial center of the photoconductor (20) and the charging wire (23), and a second imaginary line connecting the axial center of the photoconductor (20) and the axial center of the transfer member (21). The angle between
An angle formed by the second imaginary line and a third imaginary line connecting the axial center of the photoconductor (20) and the axial center of the developer carrier (34);
The angle formed by the third imaginary line and the first imaginary line is substantially the same.
The image forming apparatus according to claim 9, wherein the image forming apparatus is arranged.