WO2014010128A1

WO2014010128A1 - Developing cartridge

Info

Publication number: WO2014010128A1
Application number: PCT/JP2012/080840
Authority: WO
Inventors: 康雅藤井; 啓城森
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: CN104471489B; JP5962274B2; CN104471489A; JP2014016497A

Abstract

This developing cartridge (19) comprises: a developing frame (25) having a first side wall (47); a developing gear (77) and a gear mechanism (78) that are arranged on the outer side surface of the first side wall (47); a collar member (72) that covers at least a portion of the peripheral surface of the developing gear (77); and a gear holder (73) that receives the gear mechanism (78) together with the first side wall (47). The collar member (72) is formed of a material that has better slidability than the gear holder (73). Both the collar member (72) and the gear holder (73) are positioned in common with respect to a positioning part (60) provided on the first side wall (47).

Description

Developer cartridge

The present invention relates to a developing cartridge mounted on an image forming apparatus employing an electrophotographic system.

Conventionally, an electrophotographic printer in which a developing cartridge is detachably mounted is known. The developing cartridge includes a developing case, various rollers such as a developing roller supported in the developing case, a gear mechanism that is provided on an outer surface of the side wall of the developing case, and rotates the various rollers. And a gear cover that receives the gear mechanism together with the side wall of the developing housing.

As such a developing cartridge, for example, the developing roller is a developing roller shaft that is rotatably supported on the side wall of the developing housing, and an end portion of the developing roller shaft projects outward from the gear cover. And a developing cartridge including a color member covering an end portion of the developing roller shaft protruding from the gear cover has been proposed (for example, see Patent Document 1).

In such a developing cartridge, the driving force is transmitted from the gear mechanism to the end of the developing roller shaft, so that the developing roller is rotationally driven.

JP 2011-133663 A

However, in the developing cartridge described in Patent Document 1, each of the color member and the gear cover is positioned at a separate portion on the side wall of the developing housing. Therefore, the relative positioning accuracy between the end portion of the developing roller shaft covered with the color member and the gear mechanism received by the gear cover cannot be sufficiently achieved, and stable rotation driving of the developing roller may not be ensured.

Further, in the developing cartridge described in Patent Document 1, since each of the color member and the gear cover is positioned at different portions on the side wall of the developing housing, a space for positioning both the color member and the gear cover is provided. It is necessary to secure it on the side wall of the developing housing, and there is a limit to downsizing the developing cartridge.

Therefore, an object of the present invention is to provide a developing cartridge that can be reduced in size while improving the relative positioning accuracy between the rotating member and the driving mechanism.

(1) In order to achieve the above-described object, a developing cartridge of the present invention includes a housing having a first wall and a developer carrier main body configured to carry the developer, In contrast, the developer carrier body is configured to rotate about the first axis, and is disposed on the first direction side, which is one side in the first axis direction with respect to the first wall, and the first axis is the center. A rotating member configured to rotate integrally with the developer carrier main body and having at least a portion disposed on a second direction side opposite to the first direction side with respect to the first wall; and a rotating member A driving mechanism disposed on the second direction side with respect to the first wall, covering at least a part of the peripheral surface of the rotating member, and having a first rotating body for transmitting a driving force to the first wall. The collar member arranged on the second direction side with respect to the wall and the collar member are provided separately. Is disposed in the second direction relative to the driving mechanism, and a holder for receiving a driving mechanism together with the first wall.

The collar member is made of a material that is more slidable than the holder.

The first wall includes a common positioning portion configured to position each of the collar member and the holder.

According to such a configuration, since each of the collar member and the holder is positioned at the common positioning portion, the collar member and the holder are compared with the case where each of the collar member and the holder is positioned at a separate portion on the side wall. The positioning accuracy relative to the holder can be further improved, and the space for positioning the collar member and the holder can be reduced.

Therefore, the relative positioning accuracy between the rotating member and the drive mechanism can be further improved, and the developing cartridge can be reduced in size.

Also, since the collar member covers the rotating member configured to rotate, the collar member may come into contact with the rotating member and rub.

In this respect, since the collar member is formed of a material that is more slidable than the holder, even if the collar member and the rotating member are in contact with each other and rubbed, the collar member is worn. While being able to suppress, smooth rotation of a rotation member is securable. In addition, since the collar member is provided as a separate body from the holder, only the collar member can be formed from a material having good slidability, and the material cost can be reduced.

Therefore, according to the developing cartridge of the present invention, the developing cartridge can be reduced in size while the relative positioning accuracy between the rotating member and the driving mechanism can be improved, and the color member is worn. It is possible to suppress this, and to ensure smooth rotation of the rotating member, and to reduce the material cost.
(2) Moreover, the positioning part may protrude toward the 2nd direction side from the 1st wall.

According to such a configuration, since the positioning portion protrudes from the first wall toward the second direction side, each of the collar member and the holder disposed on the second direction side with respect to the first wall is shared. The positioning portion can be surely positioned.
(3) Further, at least a part of the collar member may be disposed between the first wall and the holder in the first axial direction.

However, from the viewpoint of improving the accuracy of image formation, it is desired to improve the positioning accuracy of the developer carrier main body with respect to the housing.

However, when an impact is applied to the collar member from the outside, the impact may act on the rotating member covered with the collar member, and may further act on the developer carrier main body via the rotating member. Then, the positioning accuracy of the developer carrier main body with respect to the housing may be lowered.

On the other hand, according to the above configuration, at least a part of the collar member is disposed between the first wall and the holder in the first axial direction, so that at least a part of the collar member is the second It is covered with a holder from the direction side.

Therefore, for example, even if an impact is applied to the developing cartridge from the second direction side, the impact on the color member is suppressed by the holder.

As a result, it is possible to suppress a decrease in the positioning accuracy of the developer carrier main body with respect to the housing.

Moreover, since it is suppressed that an impact is added to a color member, it is also suppressed that an expensive color member is damaged compared with a holder.
(4) Moreover, the 1st wall may be provided in the other side of the positioning part with respect to the rotation member in the 2nd direction side, and may be provided with the common fixing | fixed part which fixes each of a collar member and a holder.

According to such a configuration, since each of the collar member and the holder is fixed to the common fixing portion, each of the collar member and the holder can be separately provided on the side wall while each of the collar member and the holder can be fixed to the first wall. Compared to the case where the collar member and the holder are fixed to each other, the space for fixing the collar member and the holder can be reduced.

In addition, since each of the collar member and the holder is fixed to the first wall, the rotating member that is covered by the collar member and the driving mechanism that is supported by the holder together with the first wall are connected to the first wall. Positioned with high accuracy.

In particular, the rotating member is disposed between the positioning portion and the fixing portion, and at least a part of the rotating member is covered with the collar member, so that the rotating member is positioned with higher accuracy with respect to the first wall.
(5) Moreover, each of a positioning part, a fixing | fixed part, and a rotation member may be arrange | positioned so that it may rank on the straight line extended in the radial direction of rotation through the central axis of a rotation member.

According to such a configuration, since the positioning portion is disposed on one side of the rotation member in the radial direction and the fixing portion is disposed on the other side in the radial direction with respect to the rotation member, for example, the rotation with the collar member is performed. Even if the member contacts and rubs, it is possible to prevent the color member from rattling.

Therefore, it is possible to improve the positioning accuracy of the collar member with respect to the first wall, and consequently improve the positioning accuracy of the rotating member with respect to the first wall.
(6) Moreover, the collar member may have the 1st coating | coated part which coat | covers the 2nd direction side end surface of a rotation member from a 2nd direction side.

According to such a configuration, since the first covering portion of the collar member covers the end surface on the second direction side of the rotating member from the second direction side, the first covering on the end surface on the second direction side of the rotating member. The parts face each other from the second direction side.

Therefore, the movement of the rotating member in the second direction is restricted, and the positioning accuracy of the rotating member with respect to the housing can be improved.
(7) The collar member may have a second covering portion that is continuous with the first covering portion, faces the first wall from the second direction side, and is fixed to the fixing portion.

In this case, the holder covers at least the second covering portion from the second direction side.

According to such a configuration, since the second covering portion fixed to the fixing portion is covered with the holder from the second direction side, even if an impact is applied to the developing cartridge from the second direction side, the holder Thus, it is possible to suppress the impact from being applied to the second covering portion.

Therefore, even if an impact is applied to the developing cartridge from the second direction side, it is possible to suppress a decrease in the positioning accuracy of the second covering portion with respect to the first side wall, and consequently the positioning accuracy of the color member with respect to the first side wall decreases. Can be suppressed.
(8) Moreover, the holder may be fixed by the screw member in each of the positioning part and the fixing part.

In this case, the screw member is fixed to each of the positioning portion and the fixing portion via the holder and the second covering portion.

According to such a configuration, the second covering portion is covered by the holder from the second direction side, and the screw member is fixed to each of the positioning portion and the fixing portion via the holder and the second covering portion. A holder is interposed between the screw member and the second covering portion.

Therefore, it is possible to suppress the torque when the screw member is screwed into each of the positioning portion and the fixing portion from acting on the second covering portion by the holder interposed between the screw member and the second covering portion.

As a result, when the screw member is screwed into the positioning portion and the fixing portion, the collar member can be prevented from rattling, and the positioning accuracy of the collar member with respect to the first wall can be improved.
(9) The rotating member may be a developing gear arranged on the second direction side with respect to the first wall and configured to transmit the driving force from the driving mechanism to the developer carrier main body. .

In this case, the color member covers the end portion of the developing gear in the second direction.

According to such a configuration, although the configuration is simple, since the rotating member is the developing gear, the developing gear can reliably receive the driving force from the driving mechanism.

Therefore, the driving force from the drive mechanism can be transmitted to the developer carrier main body, and the developer carrier main body can be stably rotated.
(10) Further, a developer supply body main body configured to supply the developer to the developer carrier main body, and configured to be rotatable about the second axis with respect to the housing, the first wall The developer supply body main body disposed on the first direction side relative to the first wall and the developer supply body main body that rotates integrally with the second axis about the second axis. And a supply gear arranged in the.

In this case, the at least one rotating body is configured to be rotatable with respect to the housing and is a coupling gear for receiving a driving force from the outside, and the coupling gear is provided for each of the supply gear and the developing gear. The driving force is transmitted.

Also, the distance between the rotation axis of the coupling gear and the first axis and the distance between the rotation axis and the second axis are substantially the same length.

According to such a configuration, since the developer cartridge further includes the developer supply body, the developer can be reliably supplied to the developer carrier body.

The distance between the rotation axis of the coupling gear and the first axis that is the rotation axis of the developing gear, and the distance between the rotation axis of the coupling gear and the second axis that is the rotation axis of the supply gear Since the lengths are approximately the same, the external driving force input to the coupling gear can be transmitted to each of the developing gear and the supply gear in a balanced manner.

As a result, each of the developer carrying body and the developer supply body can be stably driven to rotate.
(11) The rotating member may be a rotating shaft that extends in the first axial direction and whose second direction side end is disposed on the second direction side of the first wall.

In this case, the collar member covers the end portion on the second direction side of the rotating shaft.

According to such a configuration, since the rotating member is a rotating shaft extending in the first axial direction while having a simple configuration, the developer carrier main body and the rotating shaft are reliably rotated about the first axis. It can be configured as follows.

Therefore, the developer carrier main body can be stably rotated.

According to the present invention, the relative positioning accuracy between the rotating member and the drive mechanism can be improved, and the size can be reduced.

It is a sectional side view showing one embodiment of a printer. FIG. 2 is a perspective view of the first embodiment of the developing cartridge of the present invention as viewed from the upper left side. FIG. 3 is an exploded perspective view of the drive unit shown in FIG. 2 as viewed from the upper left side. 2A is a left side view of the developing cartridge shown in FIG. 2, and FIG. 2B is a left side portion of the IVb-IVb cross-sectional view of the developing cartridge shown in FIG. FIG. 5B is a left side view of the developing cartridge shown in FIG. 4A, showing a state where the gear holder is removed. FIG. 6 is a left side view of the developing cartridge shown in FIG. 5 and shows a state where a color member is removed. 2A is a plan view of the developing cartridge shown in FIG. 2, and FIG. 2B is a sectional view taken along the line VIIb-VIIb of the developing cartridge shown in FIG. FIG. 3 is a perspective view of the developing cartridge shown in FIG. 2 as viewed from the front left side, showing a left side portion of the developing cartridge. It is the disassembled perspective view which looked at the drive unit in 2nd Embodiment of the developing cartridge of this invention from the upper left side.

1. Overall Configuration of Printer As shown in FIG. 1, the printer 1 includes a main body casing 2 having a substantially box shape.

In addition, the printer 1 includes a paper feeding unit 3 for feeding the paper S and an image forming unit 4 for forming an image on the fed paper S in the main body casing 2.

In addition, when referring to the direction with respect to the printer 1 and the developing cartridge 19 (described later), the direction when placed in the horizontal direction is used as a reference, and specifically, the arrow direction shown in each drawing is used as a reference. To do.
(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 swingably (moved) 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 (shown in FIG. 1). (See the two-dot chain line).

The paper feed cover 8 is provided so as to be swingable (movable) 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 portion as a fulcrum (see FIG. 1).
(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.
(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 that is detachably attached to the main casing 2 and a developing cartridge 19 that is detachably attached to the drum cartridge 18.

The drum cartridge 18 includes a photosensitive drum 20, a transfer roller 21, and a scorotron charger 22.

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 cylindrical shape that is long in the left-right direction, and is 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 as an example of a housing.

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 (an example of a 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.

The agitator 29 includes an agitator shaft 49 extending in the left-right direction, and a stirring blade 50 extending from the agitator shaft 49 to the radially outer side of the agitator shaft 49.

The left and right ends of the agitator shaft 49 are supported by a pair of side walls 46 (see FIG. 5 described later) so that the agitator 29 is rotatably supported by the developing frame 25.

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 sponge roller 52 (described later), and is formed so as to be recessed rearward and downward.

The developing roller facing surface 31 has a substantially arc shape along the peripheral surface of a rubber roller 54 (described later), and is formed so as to extend rearward and upward continuously 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.

The developing chamber 27 is provided with a supply roller 33, a developing roller 34, a layer thickness regulating blade 35, and a lower film 36.

The supply roller 33 includes a metal supply roller shaft 51 extending in the left-right direction and a sponge roller 52 (an example of a developer supply body) that covers the supply roller shaft 51 so that the left and right ends of the supply roller shaft 51 are exposed. And.

The supply roller 33 is disposed on the rear side of the toner storage chamber 26 so that the lower portion thereof is disposed in the supply roller groove 30, and is substantially the same height as the toner storage chamber 26 in the vertical direction ( It is positioned slightly above the toner storage chamber 26.

As will be described in detail later, the supply roller 33 rotates at the front portion of the developing chamber 27 by supporting the left and right ends of the supply roller shaft 51 on a pair of side walls 46 (described later) (see FIG. 5). It is provided as possible.

The developing roller 34 includes a metal developing roller shaft 53 extending in the left-right direction, and a rubber roller 54 (an example of a developer carrier main body) that covers the developing roller shaft 53 so that both left and right ends of the developing roller shaft 53 are exposed. It has.

The developing roller 34 is disposed so that the peripheral surface of the lower portion of the rubber roller 54 and the developing roller facing surface 31 are opposed to each other with a space therebetween.

Further, the developing roller 34 contacts the supply roller 33 from the rear upper side. Further, the developing roller 34 is provided such that the upper and rear portions thereof are exposed from the developing chamber 27 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 shaft center of the supply roller 33 (supply roller shaft 51), the shaft center of the developing roller 34 (developing roller shaft 53), and the shaft center of the photosensitive drum 20 are on substantially the same straight line parallel to the radial direction of the photosensitive drum 20. Is located.

Further, the developing roller 34 is arranged at a distance from the scorotron charger 22 in the circumferential direction of the photosensitive drum 20, and a line segment connecting the axial center of the photosensitive drum 20 and the charging wire 23, and the photosensitive roller 20. The angle formed by the line segment connecting the shaft center of the drum 20 and the shaft center of the developing roller 34 (developing roller shaft 53) is about 120 °. That is, the developing roller 34, the scorotron charger 22, and the transfer roller 21 are arranged at substantially equal intervals in the circumferential direction of the photosensitive drum 20.

Further, as will be described in detail later, the developing roller 34 is supported at the left and right ends of the developing roller shaft 53 by a pair of side walls 46 (described later) (see FIG. 5). It is provided so as to be rotatable.

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 lower 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.

Note that the center of gravity of the developing cartridge 19 is set at the front and rear and substantially at the center in the vertical direction. Specifically, the developing coupling 85 (see FIG. 5), which will be described later, is projected in the horizontal direction. Located in the projection plane.
(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 (see the solid line in FIG. 1) 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 portion of the photosensitive drum 20) is opposite to the nip point 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

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 at a position corresponding to the space between the scanner unit 16 and the photosensitive drum 20 on the inner surface of the main casing 2. 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 sponge roller 52 of the supply roller 33 through the communication port 28 by the rotation of the agitator 29, and further, the rubber roller of the developing roller 34 54 and is frictionally charged positively between the sponge roller 52 and the rubber roller 54.

The toner supplied to the rubber roller 54 is regulated by the layer thickness regulating blade 35 as the developing roller 34 rotates, and is carried on the surface of the rubber roller 54 as a thin layer having a constant thickness.

On the other hand, the surface of the photosensitive drum 20 is uniformly charged by 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 rubber roller 54 is supplied to the electrostatic latent image on the circumferential surface of the photosensitive drum 20, whereby 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. After that, 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 fed sheet by sheet at a predetermined timing (photosensitive drum 20 (described later) and transfer roller 21 ( (To be described later).

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 formed on the upper surface of the top cover 7 by the paper discharge roller 40.

In this way, the sheet S is fed from the sheet placing portion 9, passes between the photosensitive drum 20 and the transfer roller 21 (nip point), and then passes between the heating roller 38 and the pressure roller 39. After that, the paper is transported through a substantially C-shaped transport path in side view so that the paper is discharged onto the paper discharge tray 41.
2. Details of Developing Cartridge As shown in FIGS. 2 and 3, the developing cartridge 19 includes a drive unit 45 disposed on the left side (an example of the second direction side) of the developing frame 25.

Note that the up / down / front / rear direction with respect to the developing cartridge 19 is slightly different from the up / down / front / rear direction with respect to the printer 1. 1 is attached.
(1) Development Frame As shown in FIG. 3, the development frame 25 is formed in a substantially box shape extending in the left-right direction (see FIG. 1), and a pair of side walls 46 opposed to each other at an interval in the left-right direction. It has.

Each of the pair of side walls 46 is formed in a substantially rectangular shape in a side view extending in the vertical direction.

Also, the pair of side walls 46 includes a left first side wall 47 (an example of a first wall) and a right second side wall 48.

On the left side of the first side wall 47, a holder engaging portion 58, an idle gear support shaft 59 (see FIG. 5), a positioning portion 60, and a fixing portion 61 are integrally provided.

As shown in FIG. 6, the holder engaging portion 58 is provided at the front end portion on the left surface of the first side wall 47, and as shown in FIG. 3, the base portion 68 and the fitting portion 69 are integrally provided. is doing.

The base 68 is formed in a substantially cross shape when viewed from the side (see FIG. 6), and is formed so as to protrude leftward from the left surface of the first side wall 47.

The fitting portion 69 is formed in a substantially cross shape when viewed from the side in which the length in the front-rear direction and the vertical direction is shorter than that of the base portion 68 (see FIG. 6), and the base portion 68 and the central axis line are aligned with each other. It is formed so as to protrude leftward from the left end.

As shown in FIG. 6, the idle gear support shaft 59 is provided on the rear side of the holder engaging portion 58 at a distance in the front-rear direction and protrudes leftward from the left surface of the first side wall 47. It is formed in a shape (see FIG. 3).

The positioning portion 60 is provided at the lower end of the rear end portion on the left surface of the first side wall 47, and is formed in a substantially cylindrical shape that protrudes leftward from the left surface of the first side wall 47, as shown in FIG. Has been. Further, the positioning part 60 has a base end part 62 and an insertion part 63 integrally.

The base end portion 62 is a right portion of the positioning portion 60 and is formed in a substantially cylindrical shape that protrudes leftward from the left surface of the first side wall 47.

The insertion portion 63 is a left side portion of the positioning portion 60, and is formed in a substantially cylindrical shape whose outer diameter is smaller than the outer diameter of the base end portion 62, so that the base end portion 62 and the central axis coincide with each other. The base end portion 62 is formed so as to protrude leftward from the left end portion. The length in the left-right direction of the insertion part 63 is substantially the same as the sum of the lengths (thicknesses) in the left-right direction of the positioning side covering part 101 (described later) and the first interposition part 116 (described later), as shown in FIG. It is formed in length.

Further, as shown in FIG. 3, the inner peripheral surface of the positioning unit 60 is partitioned as a first screw hole 64.

The fixing portion 61 is provided at the rear end portion of the upper end portion of the first side wall 47 and integrally includes an extending portion 66 and a protruding portion 67.

As shown in FIG. 4B, the extending portion 66 is formed in a substantially flat plate shape that protrudes upward from the rear end portion at the upper end portion of the first side wall 47.

The protruding portion 67 is formed in a substantially cylindrical shape that protrudes leftward from the left surface of the extending portion 66, and the inner peripheral surface thereof is partitioned as a second screw hole 65.

Further, as shown in FIG. 6, the first side wall 47 has the left end portion of the agitator shaft 49 inserted through the rear lower side of the idle gear support shaft 59 and the left end portion of the supply roller shaft 51 inserted through the front side of the positioning portion 60. The left end portion of the developing roller shaft 53 is inserted through the front upper side of the positioning portion 60. As a result, as shown in FIG. 3, the left end portion of the agitator shaft 49 (see FIG. 6), the left end portion of the supply roller shaft 51 and the left end portion of the developing roller shaft 53 are directed leftward from the first side wall 47. Protruding. On the other hand, each of the sponge roller 52 (see FIG. 1) and the rubber roller 54 is disposed on the right side (an example of the first direction side) with respect to the first side wall 47.

Further, the developing frame 25 includes two gripping portions 55 that are gripped when the developing frame 25 is detached from the drum cartridge 18 (see FIG. 1).

The gripping portions 55 are provided at both left and right end portions of the front wall of the developing frame 25, are formed in a substantially rectangular shape when viewed from the back, and as shown in FIG. It is formed to extend toward.
(2) Drive Unit The drive unit 45 is provided on the outer side surface (left side surface) of the first side wall 47 as shown in FIG. 3, and includes a bearing member 70, a gear train 71, a collar member 72, and a holder. A gear holder 73 as an example.
(2-1) Bearing Member As shown in FIG. 6, the bearing member 70 is formed in a substantially flat plate shape having a substantially rectangular shape when viewed from the side, and a notch groove 74 is formed in the rear side portion at the lower end portion thereof. ing.

The notch groove 74 is provided corresponding to the positioning portion 60 and is formed in a substantially U shape in side view that is recessed from the lower end edge of the bearing member 70 toward the front upper side. Each of the length in the front-rear direction and the length in the vertical direction of the notch groove 74 is formed longer than the outer diameter of the base end portion 62 of the positioning portion 60.

Further, as shown in FIG. 7B, the bearing member 70 has a coupling support shaft 75 integrally.

The coupling support shaft 75 is formed in a substantially cylindrical shape that protrudes leftward from the left surface of the bearing member 70 at the front upper portion of the left surface of the bearing member 70.

As shown in FIG. 3, the bearing member 70 is mounted on the left side of the portion of the first side wall 47 corresponding to the developing chamber 27 (see FIG. 1).

Further, as shown in FIG. 6, the bearing member 70 rotatably supports the left end portion of the supply roller shaft 51 on the front side of the notch groove 74, and rotates the left end portion of the developing roller shaft 53 on the front upper side of the notch groove 74. I support it as possible. That is, the left end portion of the supply roller shaft 51 and the left end portion of the developing roller shaft 53 are rotatably supported by the first side wall 47 via the common bearing member 70. Each of the right end portion of the supply roller shaft 51 and the right end portion of the developing roller shaft 53 is rotatably supported by a corresponding portion of the second side wall 48 as shown in FIG.

Thus, the developing roller 34 (the developing roller shaft 53 and the rubber roller 54) is configured to be rotatable about the first axis A1 with respect to the developing frame 25, and the supply roller 33 (the supply roller shaft 51 and the sponge roller 52) is configured to rotate. The developing frame 25 is configured to be rotatable about the second axis A2.

Further, each of the left end portion of the supply roller shaft 51 and the left end portion of the developing roller shaft 53 protrudes leftward from the bearing member 70.

Further, as shown in FIG. 6, the left end portion of the developing roller shaft 53 is disposed between the positioning portion 60 and the protruding portion 67 in the radial direction X of the rotation of the developing roller shaft 53. Each of 67 is arranged in parallel at a distance from each other. That is, the positioning portion 60 and the protruding portion 67 are arranged on a straight line extending in the direction X through the developing roller shaft 53 (first axis A1).
(2-2) Gear Train As shown in FIG. 3, the gear train 71 includes a gear mechanism 78 as an example of a driving mechanism and a developing gear 77 as an example of a rotating member.

The gear mechanism 78 has at least one gear (an example of a rotating body) for transmitting a driving force to the developing gear 77, and specifically, a developing coupling 85 as an example of a coupling gear, and a supply gear. 86, an idle gear 87, and an agitator gear 88 (see FIG. 6).

The developing coupling 85 is formed in a substantially cylindrical shape extending in the left-right direction, and integrally includes a large-diameter gear portion 89, a small-diameter gear portion 90, and a coupling portion 91.

The large-diameter gear portion 89 is provided at the right end portion of the development coupling 85. Gear teeth are formed on the circumferential surface of the large-diameter gear portion 89 over the entire circumference.

The small-diameter gear portion 90 is formed in a substantially cylindrical shape whose outer diameter is smaller than the outer diameter of the large-diameter gear portion 89, and the left end of the large-diameter gear portion 89 is aligned with the large-diameter gear portion 89 and the central axis. It protrudes from the surface toward the left. Gear teeth are formed on the circumferential surface of the small-diameter gear portion 90 over the entire circumference.

The coupling portion 91 is formed in a substantially cylindrical shape whose outer diameter is smaller than the outer diameter of the small-diameter gear portion 90, and from the left end surface of the small-diameter gear portion 90 so that the large-diameter gear portion 89 and the central axis coincide with each other. It protrudes toward the left.

A coupling recess 94 that is recessed toward the right is formed on the left side surface of the coupling portion 91. With the developing cartridge 19 mounted in the main casing 2 (see FIG. 1), the tip of a main coupling (an example of the outside, not shown) provided in the main casing 2 is relatively rotated in the coupling recess 94. The driving force is inputted from the main casing 2 through the main body coupling (not shown).

As shown in FIG. 7B, the development coupling 85 is supported by the coupling support shaft 75 so as to be relatively rotatable by inserting the coupling support shaft 75 of the bearing member 70 into the internal space. ing. Therefore, as shown in FIG. 3, the development coupling 85 is rotated about the rotation axis A3 with respect to the development frame 25 when a driving force is input.

The supply gear 86 is formed in a substantially cylindrical shape extending in the left-right direction, and gear teeth are formed on the entire circumference thereof.

The supply gear 86 is attached to the left end portion of the supply roller shaft 51 so as not to be relatively rotatable so as to mesh with the small diameter gear portion 90 of the developing coupling 85 from the lower rear side.

Therefore, when a driving force is input to the development coupling 85, the supply gear 86 is integrated with the supply roller 33 (the supply roller shaft 51 and the sponge roller 52) around the second axis A2 by the driving force. Rotate. That is, the development coupling 85 is configured to transmit a driving force to the supply gear 86, and the supply gear 86 transmits the driving force from the development coupling 85 to the sponge roller 52 via the supply roller shaft 51. It is configured as follows.

The idle gear 87 is formed in a substantially cylindrical shape extending in the left-right direction, and integrally includes a large-diameter portion 92 on the left side and a small-diameter portion 93 on the right side.

The large diameter portion 92 is formed in a substantially cylindrical shape extending in the left-right direction. Gear teeth are formed on the circumferential surface of the large diameter portion 92 over the entire circumference.

The small-diameter portion 93 is formed in a substantially cylindrical shape whose outer diameter is smaller than the outer diameter of the large-diameter portion 92, and rightward from the right end surface of the large-diameter portion 92 so that the central axis coincides with the large-diameter portion 92. It is formed in the substantially cylindrical shape extended toward. Gear teeth are formed on the circumferential surface of the small diameter portion 93 over the entire circumference.

The idle gear 87 is attached to the idle gear support shaft 59 of the first side wall 47 so as to be relatively rotatable so that the large diameter portion 92 meshes with the small diameter gear portion 90 of the developing coupling 85 from the front side.

As shown in FIG. 7B, the agitator gear 88 is formed in a substantially cylindrical shape extending in the left-right direction, and gear teeth are formed on the entire circumference thereof.

The agitator gear 88 is attached to the left end portion of the agitator shaft 76 so as not to rotate relative to the small diameter portion 93 of the idle gear 87 from the rear lower side.

Further, the rear upper portion of the agitator gear 88 is disposed between the large-diameter gear portion 89 and the first side wall 47 in the left-right direction.

That is, as shown in FIG. 6, the development coupling 85 is disposed so as to overlap all of the supply gear 86, the idle gear 87 (large diameter portion 92), and the agitator gear 88 when projected in the left-right direction. .

As shown in FIG. 3, the developing gear 77 is formed in a substantially cylindrical shape extending in the left-right direction, and integrally includes a developing gear portion 79, an intermediate portion 80, and a color insertion portion 81.

The developing gear portion 79 is provided at the right end portion of the developing gear 77, and gear teeth are formed on the entire circumferential surface thereof.

The intermediate portion 80 is formed in a substantially cylindrical shape whose outer diameter is smaller than the outer diameter of the developing gear portion 79, and from the left end surface of the developing gear portion 79 to the left so that the central axis coincides with the developing gear portion 79. It protrudes toward.

The collar insertion portion 81 is formed in a substantially cylindrical shape whose outer diameter is smaller than the outer diameter of the intermediate portion 80, and from the left end surface of the intermediate portion 80 to the left so that the developing gear portion 79 coincides with the central axis. It protrudes toward the surface.

In the developing gear 77, the developing gear portion 79 meshes with the large-diameter gear portion 89 from the rear side (see FIG. 6), and the left end surface of the color insertion portion 81 and the left end surface of the developing roller shaft 53 are in the left-right direction. It is attached to the left end portion of the developing roller shaft 53 so as not to rotate relative to each other (see FIG. 4B).

Specifically, the portions corresponding to the developing gear portion 79 and the intermediate portion 80 in the developing roller shaft 53 have a substantially D-shaped cross-section with a part of the peripheral surface cut off as shown in FIG. D-cut processed. The inner peripheral surfaces of the developing gear portion 79 and the intermediate portion 80 are formed in a substantially D-shaped cross section so as to correspond to the D-cut processed portion of the developing roller shaft 54. By inserting a substantially D-shaped portion of the developing roller shaft 54 into the developing gear portion 79 and the intermediate portion 80, the developing gear 77 is attached to the developing roller shaft 53 so as not to be relatively rotatable.

Therefore, as shown in FIG. 3, when a driving force is input to the developing coupling 85, the developing gear 77 has the developing roller 34 (the developing roller shaft 53 and the rubber roller centered on the first axis A1) by the driving force. 54) and rotate together. That is, the developing coupling 85 is configured to transmit a driving force to the developing gear 77, and the developing gear 77 transmits the driving force from the developing coupling 85 to the rubber roller 54 via the developing roller shaft 53. It is configured.

Further, as shown in FIG. 6, the distance D1 between the rotation axis A3 and the first axis A1 of the developing coupling 85 and the distance D2 between the rotation axis A3 and the second axis A2 are substantially the same length. Is set.

Further, the positioning portion 60, the protruding portion 67 of the fixing portion 61, and the developing gear 77 have their axial centers positioned on the same virtual straight line in the radial direction X of the rotation of the developing gear 77 (developing roller shaft 53). Are arranged in parallel. Specifically, the positioning portion 60 is disposed on the rear lower side (one radial direction X side) with respect to the developing gear 77, and the protruding portion 67 is on the front upper side (radial direction X other side with respect to the developing gear 77. Side). That is, the protruding portion 67 is provided on the left side of the first side wall 47 on the opposite side of the positioning portion 60 with respect to the developing gear 77.
(2-3) Color Member As shown in FIG. 3, the color member 72 is made of a material having better slidability than the gear holder 73, for example, POM (polyacetal) resin, PA (polyamide) resin, and PTFE (polytetra). Fluoroethylene) resin or the like. Specifically, the collar member 72 has a measurement result (wear resistance) measured by a taper wear test of, for example, 5 mg / 1000 times to 15 mg / 1000 times, preferably 8 mg / 1000 times to 15 mg / 1000 times. Formed from. The wear test is measured in accordance with the JIS K7204 plastic-wear wheel wear test method.

Further, the collar member 72 integrally includes a first covering portion 95, a second covering portion 96, and a third covering portion 97.

The first covering portion 95 is formed in a substantially cylindrical shape extending in the left-right direction and closed at the left end face, and integrally includes a continuous portion 98 and an end covering portion 99.

The continuous portion 98 is a right portion of the first covering portion 95 and is formed in a substantially cylindrical shape extending in the left-right direction. The continuous portion 98 has an inner diameter slightly larger than the outer diameter of the intermediate portion 80 (see FIG. 7B).

The end covering portion 99 is the left portion of the first covering portion 95 (the left side of the continuous portion 98), and is formed in a substantially cylindrical shape whose outer diameter is smaller than the outer diameter of the continuous portion 98. Is formed so as to protrude from the left end portion of the continuous portion 98 toward the left so that the central axis coincides with the central axis.

Further, the left end surface of the end covering portion 99 is closed, and the inner diameter thereof is slightly larger than the outer diameter of the collar insertion portion 81 (see FIG. 7B).

The second covering portion 96 is formed in a substantially flat plate shape extending in the vertical direction continuously from the continuous portion 98, and includes a fixed portion side covering portion 100 and a positioning side covering portion 101.

As shown in FIG. 5, the fixed portion side covering portion 100 is formed in a substantially flat plate shape extending from the front upper portion of the right end portion on the outer peripheral surface of the continuous portion 98 toward the front upper side.

The fixing part side covering part 100 is formed with a fixing hole 102 and an arc part 104.

The fixing hole 102 is formed at the upper end portion of the fixing portion side covering portion 100 so as to correspond to the second screw hole 65 of the protruding portion 67, and is formed in a substantially circular shape when viewed from the side.

The arc portion 104 has a substantially arc shape along the peripheral surface of the small-diameter gear portion 90 and is formed so as to be recessed rearward from the front end edge of the fixing portion side covering portion 100 on the lower side of the fixing hole 102.

The positioning-side covering portion 101 is formed in a substantially flat plate shape extending rearward and downward from the rear lower side portion of the right end portion on the outer peripheral surface of the continuous portion 98 (see FIG. 3).

A positioning hole 103 is formed in the positioning side covering portion 101.

The positioning hole 103 is formed at the lower end portion of the positioning side covering portion 101 corresponding to the first screw hole 64 of the positioning portion 60 and extends in the front-rear direction (specifically, the direction connecting the rear upper and front lower sides). It is formed in a substantially elongated hole shape. The positioning hole 103 is formed such that its short direction length is substantially the same as the outer diameter of the insertion part 63 of the positioning part 60, and its longitudinal direction length is longer than the outer diameter of the insertion part 63. .

As shown in FIG. 3, the third covering portion 97 is formed in a substantially flat plate shape that protrudes rightward continuously from the second covering portion 96, and includes an upper covering portion 105, a lower covering portion 106, and the like. have.

The upper covering portion 105 is formed in a substantially flat plate shape extending continuously from the rear end portion on the right surface of the fixed portion side covering portion 100 toward the right.

The lower covering portion 106 is formed in a substantially L shape in a side view, and is formed so as to continuously extend rightward from the rear end portion and the lower end portion on the right surface of the positioning side covering portion 101.

Each of the upper covering portion 105 and the lower covering portion 106 has a length in the left-right direction slightly longer than the length in the left-right direction of the developing gear portion 79.

As will be described in detail later, the collar member 72 has a bearing member 70 as shown in FIG. 2 so that the end covering portion 99 fits the collar insertion portion 81 inside (see FIG. 4B). It is arrange | positioned on the left side of the rear side part (refer FIG. 5).
(2-4) Gear Holder As shown in FIG. 3, the gear holder 73 is provided separately from the collar member 72, and is made of, for example, ABS resin (acrylonitrile-butadiene-styrene copolymer resin). Specifically, the gear holder 73 has a measurement result (wear resistance) measured by a taper wear test of, for example, 16 mg / 1000 times to 25 mg / 1000 times, preferably 18 mg / 1000 times to 20 mg / 1000 times. Is formed. The gear holder 73 is formed in a substantially box shape that opens to the right and rear, and has a size (front-rear direction length and vertical length) that can cover the gear train 71 and the collar member 72 collectively. ing.

The gear holder 73 integrally has a cover side wall 110 and a cover front wall 111 (see FIG. 8).

As shown in FIG. 4A, the cover side wall 110 is formed in a substantially rectangular shape when viewed from the side in the longitudinal direction. Further, the cover side wall 110 is formed with a coupling exposure port 112, a collar engagement groove 113, a first screw insertion hole 114 (see FIG. 3), and a second screw insertion hole 115 (see FIG. 3). ing.

The coupling exposure port 112 is formed in a substantially circular shape when viewed from the side so as to expose the left surface (coupling recess 94) of the coupling portion 91 of the developing coupling 85 at a substantially central portion in the front-rear direction of the cover side wall 110. Yes.

The collar engaging groove 113 is formed on the rear side of the coupling exposure port 112, and is formed in a substantially C shape in a side view recessed from the rear end edge of the cover side wall 110 toward the front lower side. The groove width (inner diameter) of the collar engaging groove 113 is formed slightly larger than the outer diameter of the end covering portion 99 (FIG. 4).
(See (b)).

As shown in FIG. 3, the first screw insertion hole 114 is formed on the lower side of the collar engagement groove 113 so as to correspond to the first screw hole 64, and is formed in a substantially circular shape when viewed from the side. The diameter of the first screw insertion hole 114 is substantially the same as the outer diameter of the insertion portion 63. Further, the peripheral end portion of the first screw insertion hole 114 is partitioned as a first interposition portion 116.

The second screw insertion hole 115 is formed on the upper side of the collar engagement groove 113 so as to correspond to the second screw hole 65, and is formed in a substantially circular shape when viewed from the side. A peripheral end portion of the second screw insertion hole 115 is partitioned as a second interposition portion 117.

Further, the cover side wall 110 integrally includes an edge portion 120 and a fitted portion 121 (see FIG. 7B).

The edge portion 120 is formed in a substantially flat plate shape that protrudes rightward from the rear end portion on the right surface of the cover side wall 110. As shown in FIG. 2, the length of the edge portion 120 in the left-right direction is substantially the same length (slightly longer) as the length of the continuous portion 98 in the left-right direction.

7B, the fitted portion 121 is provided at the front end portion on the right surface of the cover side wall 110 corresponding to the fitting portion 69 of the holder engaging portion 58. As shown in FIG. In addition, the fitted portion 121 is formed in a substantially U-shaped cross section that is opened forward and is formed so as to protrude rightward from the right surface of the cover side wall 110. Further, the front end portion of the fitted portion 121 is connected to the rear surface of the cover front wall 111.

The inner dimension of the fitted portion 121 is formed such that the vertical length thereof is substantially the same as the vertical length of the fitting portion 69, and the longitudinal length thereof is larger than the longitudinal length of the fitting portion 69. Is also formed slightly longer.

As shown in FIG. 8, the cover front wall 111 is formed in a substantially flat plate shape that extends continuously from the front end of the cover side wall 110 toward the right.

Further, the cover front wall 111 has a side wall engaging portion 122 integrally.

The side wall engaging portion 122 is formed in a substantially flat plate shape extending continuously from the upper portion of the right end portion of the cover front wall 111 toward the right.

As will be described in detail later, the gear holder 73 has a gear mechanism 78 (developing coupling 85 (excluding the coupling recess 94 of the coupling portion 91), a supply gear 86, an idle gear 87, and an agitator gear, as shown in FIG. 88) is attached to the first side wall 47 from the left side so as to cover the whole.

As shown in FIG. 4A, in the developing cartridge 19 (excluding the grip portion 55), the uppermost portion is the rear portion of the upper end portion of the gear holder 73, and is located at the lowermost portion. This portion is the front side portion of the lower end portion of the gear holder 73.

That is, the gear holder 73 covers most (most) of the developing frame 25 excluding the grip portion 55 in the left side view.
3. Assembly of Color Member and Gear Holder to Development Frame Next, assembly of the color member 72 and gear holder 73 to the development frame 25 will be described.

In order to assemble the collar member 72 to the developing frame 25, the insertion portion 63 of the positioning portion 60 is inserted into the positioning hole 103 with respect to the first side wall 47 to which the bearing member 70 and the gear train 71 are attached, as shown in FIG. The collar member 72 is assembled from the left side so that the second screw hole 65 is exposed through the fixing hole 102 while being inserted.

4B, the intermediate portion 80 of the developing gear 77 is fitted inside the continuous portion 98 of the first covering portion 95, and the color insertion portion 81 of the developing gear 77 is covered with the first covering portion. The portion 95 is fitted inside the end covering portion 99. Thereby, the peripheral surface of the intermediate part 80 and the collar insertion part 81 is coat | covered with the 1st coating | coated part 95 (continuous part 98 and the edge part covering part 99) from those radial direction outer sides. The left end surfaces of the color insertion portion 81 and the developing roller shaft 53 are covered from the left side by the end cover portion 99 and face the left wall of the end cover portion 99 from the left side.

Further, the second covering portion 96 (the fixed portion side covering portion 100 and the positioning side covering portion 101) is opposed to the first side wall 47 with an interval in the left-right direction from the left side (see FIG. 3).

At this time, as shown in FIG. 2, the upper covering portion 105 is disposed so as to face the rear upper side of the large diameter gear portion 89 with an interval so as to cover the large diameter gear portion 89 from the rear side (FIG. 5). reference). Further, the lower covering portion 106 has a rear portion behind the proximal end portion 62 (see FIG. 3) so as to cover the proximal end portion 62 (see FIG. 3) of the positioning portion 60 from the rear side and the lower side. The lower part is opposed to the lower side of the base end part 62 (see FIG. 3) with a gap (see FIG. 5).

Thereby, the assembly of the collar member 72 to the first side wall 47 is completed.

Next, the gear holder 73 is assembled to the first side wall 47.

To assemble the gear holder 73 to the first side wall 47, as shown in FIG. 3, the insertion portion 63 is inserted into the first screw insertion hole 114, and the second screw hole 65 is inserted through the second screw insertion hole 115. The gear holder 73 is assembled to the first side wall 47 from the left side so as to be exposed.

Then, the fitted portion 121 of the cover side wall 110 fits the fitting portion 69 of the holder engaging portion 58 inward as shown in FIG. 7B, and the side wall engaging portion 122 of the cover front wall 111. As shown in FIG. 8, the first side wall 47 is disposed on the rear side of the upper portion of the front end portion.

At this time, the end covering portion 99 is disposed in the collar engaging groove 113 as shown in FIG. 2, and the second covering portion 96 is arranged in the left-right direction as shown in FIG. 70 and the cover side wall 110, and is covered from the left side by the cover side wall 110.

Further, the left surface (coupling recess 94) of the coupling portion 91 is exposed through the coupling exposure port 112 as shown in FIG.

Thereby, the assembly of the gear holder 73 to the first side wall 47 is completed.

At this time, the gear holder 73 is arranged on the left side with respect to the gear mechanism 78 as shown in FIG.

Next, the first screw member 123 as an example of the screw member is screwed into the first screw hole 64 through the positioning hole 103 and the first screw insertion hole 114 of the collar member 72.

At this time, a first interposition part 116 is interposed between the head 131 of the first screw member 123 and the peripheral end of the positioning hole 103 as shown in FIG.

Therefore, the torque when the first screw member 123 is screwed into the first screw hole 64 is prevented from acting on the second covering portion 96 by the first interposition portion 116, and the collar member 72 is rattled. Can be suppressed.

On the other hand, as shown in FIG. 7B, the gear holder 73 is fitted with the fitted portion 121 with the holder engaging portion 58, and the side wall engaging portion 122 of the first side wall 47 as shown in FIG. 8. Since it is arranged on the rear side of the front end portion, even if the torque when the first screw member 123 is screwed into the first screw hole 64 acts on the cover side wall 110, rattling is suppressed. .

Then, in the state where the first screw member 123 is screwed into the first screw hole 64, the peripheral end portion of the positioning hole 103 and the first interposition portion 116 are positioned in the positioning portion 60 as shown in FIG. Between the base end portion 62 and the head 131 of the first screw member 123.

That is, each of the collar member 72 and the gear holder 73 is positioned (fixed) on the common positioning portion 60.

Next, the second screw member 124 as an example of the screw member is screwed into the second screw hole 65 through the fixing hole 102 and the second screw insertion hole 115 as shown in FIG.

At this time, a second interposition part 117 is interposed between the head 132 of the second screw member 124 and the peripheral end of the fixing hole 102 as shown in FIG.

Then, in a state where the screwing of the second screw member 124 to the second screw hole 65 is completed, the peripheral end portion of the fixing hole 102 and the second interposition portion 117 are the protruding portion 67 of the fixing portion 61 and the second screw member 124. Is sandwiched between the head 132 and the head 132.

That is, each of the collar member 72 and the gear holder 73 is positioned (fixed) on the common protrusion 67.

That is, the collar member 72 and the gear holder 73 are screwed on both sides of the developing gear 77 in the radial direction X (see FIG. 6).

At this time, the peripheral end portion of the positioning hole 103 is sandwiched between the base end portion 62 and the first interposition portion 116, and the peripheral end portion of the fixing hole 102 is between the protruding portion 67 and the second interposition portion 117. The collar member 72 is restricted from moving in the left-right direction.

In addition, as shown in FIG. 2, the rear end portion on the left surface of the second covering portion 96 (the fixed portion side covering portion 100 and the positioning side covering portion 101) is brought into contact with the right end portion of the edge portion 120 of the gear holder 73, The right end portions of the three covering portions 97 (the upper covering portion 105 and the lower covering portion 106) are in contact with the rear end portion on the left surface of the bearing member 70.

Thus, the assembly of the color member 72 and the gear holder 73 to the developing frame 25 is completed.

Accordingly, the gear mechanism 78 is received from the right side by the first side wall 47 and is also received from the left side by the gear holder 73, and the gear holder 73 is prevented from unexpectedly falling off from the first side wall 47. That is, the gear mechanism 78 is supported by the developing frame 25 by the first side wall 47 and the gear holder 73 acting together.
4). Operation and Effect (1) As shown in FIG. 4B, in the developing cartridge 19, the collar member 72 and the gear holder 73 are positioned at a common positioning portion 60.

Therefore, compared with the case where each of the collar member 72 and the gear holder 73 is positioned at a separate part in the first side wall 47, the relative positioning accuracy between the collar member 72 and the gear holder 73 can be further improved. In addition, the space for positioning the collar member 72 and the gear holder 73 can be reduced.

As a result, the relative positioning accuracy between the developing gear 77 and the gear mechanism 78 can be improved, and the developing cartridge 19 can be downsized.

Further, the collar member 72 is formed of a material (for example, POM resin) having better slidability than the gear holder 73. Therefore, even when the color member 72 and the development gear 77 are in contact with each other and rubbed, it is possible to prevent the color member 72 from being worn and to ensure smooth rotation of the development gear 77. In addition, since the collar member 72 is provided as a separate body from the gear holder 73, only the collar member 72 can be formed from a material having good slidability, and the material cost can be reduced.

Therefore, according to the developing cartridge 19 of the present invention, the developing cartridge 19 can be downsized while improving the relative positioning accuracy between the developing gear 77 and the gear mechanism 78. Furthermore, the collar member 72 can be prevented from being worn, the smooth rotation of the developing gear 77 can be secured, and the material cost can be reduced.
(2) Moreover, the positioning part 60 protrudes toward the left (2nd direction side) from the 1st side wall 47, as shown in FIG.

Therefore, each of the collar member 72 and the gear holder 73 disposed on the left side (second direction side) with respect to the first side wall 47 can be reliably positioned on the common positioning portion 60.

Further, as shown in FIG. 4B, the insertion portion 63 of the positioning portion 60 is inserted into the positioning hole 103 formed in the collar member 72 and the first screw insertion hole 114 formed in the gear holder 73. Yes. Further, the length in the short direction of the positioning hole 103 (specifically, substantially the length in the vertical direction) is formed to be substantially the same as the outer diameter of the insertion portion 63, and the hole diameter of the first screw insertion hole 114 is The outer diameter of the insertion portion 63 is substantially the same.

Therefore, the collar member 72 is restricted from moving in the substantially vertical direction, and the gear holder 73 is restricted from moving in the radial direction (specifically, the front-rear and vertical directions) of the insertion portion 63.

That is, each of the collar member 72 and the gear holder 73 is positioned at least in the direction intersecting the left-right direction by the insertion portion 63 of the positioning portion 60.

As a result, each of the collar member 72 and the gear holder 73 can be accurately positioned on the common positioning portion 60 in the direction crossing the left-right direction.
(3) Further, as shown in FIG. 4B, the second covering portion 96 of the collar member 72 is provided between the first side wall 47 and the cover side wall 110 of the gear holder 73 in the left-right direction (first axial direction). Is arranged.

Therefore, the second covering portion 96 (the fixed portion side covering portion 100 and the positioning side covering portion 101) is covered with the cover side wall 110 from the left side.

As a result, even if an impact is applied to the developing cartridge 19 from the left side, the gear member 73 suppresses the impact to the collar member 72.

Therefore, it is possible to suppress a decrease in the positioning accuracy of the rubber roller 54 with respect to the developing frame 25.

Further, since the impact on the collar member 72 is suppressed, damage to the expensive collar member 72 as compared with the gear holder 73 is also suppressed.
(4) The first side wall 47 is provided with a fixing portion 61 as shown in FIG.

The fixing portion 61 has a protruding portion 67 provided on the left side of the first side wall 47 with respect to the developing gear 77 on the opposite side of the positioning portion 60.

Each of the collar member 72 and the gear holder 73 is fixed to a common protruding portion 67.

Therefore, the space for fixing the collar member 72 and the gear holder 73 can be reduced while each of the collar member 72 and the gear holder 73 can be fixed to the first side wall 47.

Further, the developing gear 77 covered by the color member 72 and the gear mechanism 78 received by the gear holder 73 together with the first side wall 47 are accurately positioned with respect to the first side wall 47.

In particular, as shown in FIG. 3, the developing gear 77 is disposed between the positioning portion 60 and the protruding portion 67, and the peripheral surface of the collar insertion portion 81 is covered with the end portion covering portion 99 of the collar member 72. Therefore (see FIG. 4B), the positioning with respect to the first side wall 47 is performed with higher accuracy.
(5) Further, each of the positioning portion 60, the protruding portion 67, and the developing gear 77 is arranged so as to be aligned on a straight line that passes through the rotation axis of the developing gear 77 and extends in the radial direction X, as shown in FIG. . Specifically, the positioning portion 60 is disposed on the rear lower side (one radial direction X side) with respect to the developing gear 77, and the protruding portion 67 is on the front upper side (radial direction X other side with respect to the developing gear 77. Side).

Therefore, even if the color member 72 and the developing gear 77 are in contact with each other and rubbed, it is possible to prevent the color member 72 from rattling.

As a result, it is possible to improve the positioning accuracy of the color member 72 with respect to the first side wall 47, and consequently improve the positioning accuracy of the developing gear 77 with respect to the first side wall 47.

In particular, the color member 72 and the gear holder 73 are fixed to the positioning portion 60 and the fixing portion 61 on both sides of the developing gear 77 on a straight line extending in the radial direction X through the developing gear 77. Therefore, even if an impact is applied to the collar member 72 and / or the gear holder 73 from the left side, the collar member 72 and / or the gear holder 73 is restrained from moving toward the right.

Therefore, it is possible to suppress the impact applied to the color member 72 and / or the gear holder 73 from acting on the developing gear 77 covered with the color member 72, and consequently to act on the developing roller 34 via the developing gear 77. Can be suppressed.

As a result, it is possible to suppress the movement of the developing roller 34 with respect to the developing frame 25, and it is possible to reliably suppress a decrease in the positioning accuracy of the rubber roller 54 of the developing roller 34 with respect to the developing frame 25.
(6) Moreover, the collar member 72 is provided with the 1st coating | coated part 95 which has the continuous part 98 and the edge part coating | coated part 99, as shown in FIG.

The end covering portion 99 covers the left end face of the collar insertion portion 81 from the left side as shown in FIG. 4B in a state where the collar member 72 is assembled to the first side wall 47. Thereby, the left end surface of the collar insertion portion 81 is opposed to the left wall of the end covering portion 99 from the left side.

Therefore, the movement of the developing gear 77 to the left is restricted, and the positioning accuracy of the developing gear 77 with respect to the developing frame 25 can be improved.
(7) Moreover, the collar member 72 has the 2nd coating | coated part 96 continuous with the continuous part 98 of the 1st coating | coated part 95, as shown in FIG.

And the 2nd coating | coated part 96 (The fixing | fixed part side coating | coated part 100 and the positioning side coating | coated part 101) is fixed to the protrusion part 67 as shown in FIG.4 (b), and with the cover side wall 110 of the gear holder 73, Covered from the left side.

Therefore, for example, even if an impact is applied to the developing cartridge 19 from the left side, it is possible to suppress the impact on the second covering portion 96 by the cover side wall 110 of the gear holder 73.

As a result, it can suppress that the positioning accuracy of the 2nd coating | coated part 96 with respect to the 1st side wall 47 falls, and can suppress that the positioning accuracy of the collar member 72 with respect to the 1st side wall 47 falls by extension.
(8) Further, as shown in FIG. 4B, the gear holder 73 is fixed by the first screw member 123 and the second screw member 124 in each of the positioning portion 60 and the protruding portion 67.

The first screw member 123 (second screw member 124) is positioned via the first interposition part 116 (second interposition part 117) and the fixed part side covering part 100 (positioning side covering part 101) of the gear holder 73. It is fixed to the part 60 (projection part 67).

Therefore, between the first screw member 123 (second screw member 124) and the peripheral end portion of the positioning hole 103 (peripheral end portion of the fixing hole 102), the first interposition portion 116 (second interposition portion 117) is formed. Intervened.

As a result, the torque when the first screw member 123 and the second screw member 124 are screwed into the positioning portion 60 and the protruding portion 67, respectively. The portion 117) can suppress the action on the second covering portion 96.

Therefore, when the first screw member 123 and the second screw member 124 are screwed into the positioning portion 60 and the protruding portion 67, the collar member 72 can be prevented from rattling, and the collar member with respect to the first side wall 47 can be suppressed. The positioning accuracy of 72 can be improved.
(9) Further, as shown in FIG. 6, the developing gear 77 has a driving force input to the developing coupling 85 since the developing gear portion 79 meshes with the large-diameter gear portion 89 of the developing coupling 85. I can receive it reliably.

Therefore, the driving force from the developing coupling 85 can be transmitted to the rubber roller 54 via the developing roller shaft 53, and the rubber roller 54 can be stably rotated.
(10) In the developing cartridge 19, as shown in FIG. 3, the supply roller 33 (see FIG. 1) including the supply roller shaft 51 and the sponge roller 52, and the supply gear 86 provided at the left end portion of the supply roller shaft 51. And.

Therefore, the toner from the toner storage chamber 26 can be reliably supplied to the rubber roller 54 by the sponge roller 52.

As shown in FIG. 6, the distance D1 between the rotation axis A3 and the first axis A1 of the developing coupling 85 and the distance D2 between the rotation axis A3 and the second axis A2 are substantially the same length. That's it.

Therefore, the driving force input to the development coupling 85 can be transmitted to the development gear 77 and the supply gear 86 in a well-balanced manner.

As a result, each of the rubber roller 54 and the sponge roller 52 can be stably rotated.
5. Second Embodiment Next, a second embodiment of the present invention will be described.

FIG. 9 is an exploded perspective view of the drive unit in the second embodiment of the developing cartridge of the present invention as viewed from the upper left side.

In FIG. 9, parts corresponding to the parts shown in FIGS. 1 to 8 are denoted by the same reference numerals as those parts, and the description thereof is omitted.

In the first embodiment, as shown in FIGS. 3 and 7B, only the portion corresponding to the developing gear portion 79 and the intermediate portion 80 at the left end portion of the developing roller shaft 53 has a D-shaped cross section. It has been cut.

On the other hand, in the second embodiment, as shown in FIG. 9, all the portions at the left end portion of the developing roller shaft 53 (the portion corresponding to the developing gear portion 79 in the left-right direction and the left portion). A part of the peripheral surface is cut off and D-cut processed into a substantially D shape in a side view.

Further, the developing gear 77 has a semi-cylindrical portion 130 provided corresponding to the portion of the developing roller shaft 53 cut off by the D cut processing.

Specifically, the semi-cylindrical portion 130 is formed in a substantially D shape in a side view that bulges backward, and is formed so as to protrude leftward from the rear side portion of the left end surface of the intermediate portion 80. .

The developing gear 77 is attached to the developing roller shaft 53 such that the left end surface of the semi-cylindrical portion 130 and the left end surface of the developing roller shaft 53 form a substantially circular shape when viewed from the side. That is, as viewed from the side, the flat portion of the D-rolled developing roller 53 comes into contact with the flat portion of the D-shaped semi-cylindrical portion 130, so that the developing gear 77 cannot rotate relative to the developing roller shaft 53. become.

The semi-cylindrical portion 130 and the corresponding left end portion of the developing roller shaft 53 (hereinafter referred to as a color insertion portion) are located inside the end covering portion 99 in a state where the collar member 72 is assembled to the first side wall 47. Placed in.

Thus, the left end surface of the collar insertion portion is covered from the left side by the end covering portion 99, and the outer peripheral surface thereof is covered from the radially outer side by the end covering portion 99. That is, the peripheral surface of the developing roller shaft 53 is covered with the end covering portion 99. In the second embodiment, the developing roller shaft 53 corresponds to an example of a rotating member.

According to the second embodiment, since all the portions at the left end portion of the developing roller shaft 53 are D-cut processed, compared with a case where a part of the left end portion of the developing roller shaft 53 is D-cut processed. Thus, the processing is easy and the manufacturing cost can be reduced.

Further, since the developing gear 77 is attached to the developing roller shaft 53 so that the left end surface of the semi-cylindrical portion 130 and the left end surface of the developing roller shaft 53 form a substantially circular shape when viewed from the side, the developing coupling 85 When the driving force is transmitted to the developing gear 77, the developing gear 77 and the developing roller shaft 53 are rotated integrally while maintaining their positional accuracy.

That is, the developing gear 77 can reliably transmit the driving force from the developing coupling 85 to the developing roller shaft 53.

Further, since the developing roller shaft 53 is formed to extend in the left-right direction (first axis direction), the rubber roller 54 can be reliably rotated about the first axis A1.

As a result, the rubber roller 54 can be driven to rotate stably.

Also in the second embodiment, the same operational effects as those of the first embodiment described above can be achieved.
6). Modification The above-described developing cartridge 19 is an embodiment of the present invention, and the present invention is not limited to the above-described embodiment.

The image forming apparatus to which the developing cartridge 19 is mounted 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 may be configured as an integral 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.

Furthermore, it is also possible to provide a photoconductor on a main body casing 2 as an example of the apparatus main body, and to attach or detach only the developing cartridge 19 to the main body 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 rubber roller 54 provided in the developing roller 34 described above, for example, a developer carrier main body such as a sponge roller, a brush-like roller, a belt, or a developing sleeve can be applied.

Further, instead of the sponge roller 52 provided in the supply roller 33 described above, for example, a developer supply body such as a brush-like roller, a belt, or a supply sleeve 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.

The above-described gear train 71 is an example of a drive transmission mechanism. However, the drive transmission mechanism can be configured by a belt, a pulley, a rack, a pinion, a chain, and the like in addition to a gear.

The gears included in the gear mechanism 78 (specifically, the development coupling 85, the supply gear 86, the idle gear 87, and the agitator gear 88) are examples of a rotating body. Others include belts and friction wheels.

Each of the developing gear 77 and the developing roller shaft 53 is an example of a rotating member, but the rotating member is fitted to the hollow rubber roller 66 in addition to the developing gear 77 and the developing roller shaft 53. Such as flanges are included.

Furthermore, the above-described printer 1 can be configured as a multi-function machine equipped with an image reading unit and the like.

19 developing cartridge 25 developing frame 47 first side wall 52 sponge roller 53 developing roller shaft 54 rubber roller 60 positioning portion 61 fixing portion 72 color member 73 gear holder 77 developing gear 78 gear mechanism 85 developing coupling 86 supply gear 95 first covering portion 96 first 2 covering portion 123 first screw member 124 second screw member A1 first axis A2 first axis A3 rotation axis D1 distance D2 between the first axis A1 and the rotation axis A3 between the second axis A2 and the rotation axis A3 Distance of

Claims

A housing (25) having a first wall (47);
A developer carrier main body (54) configured to carry a developer, wherein the developer carrier main body (54) is configured to rotate about a first axis (A1) with respect to the housing, and A developer carrier body disposed on a first direction side that is one side in the first axial direction;
The developer carrying body is integrally rotated about the first axis, and at least partly on a second direction side opposite to the first direction side with respect to the first wall. A rotating member (53, 77) on which is disposed,
A driving mechanism (78) having at least one rotating body for transmitting a driving force to the rotating member and disposed on the second direction side with respect to the first wall;
A collar member (72) covering at least a part of the peripheral surface of the rotating member and disposed on the second direction side with respect to the first wall;
A holder (73) provided as a separate body from the collar member, disposed on the second direction side with respect to the drive mechanism, and receiving the drive mechanism together with the first wall;
With
The collar member is formed from a material that is more slidable than the holder,
The developing cartridge according to claim 1, wherein the first wall includes a common positioning portion (60) configured to position each of the collar member and the holder.
2. The developing cartridge according to claim 1, wherein the positioning portion protrudes from the first wall toward the second direction.
2. The developing cartridge according to claim 1, wherein at least a part of the collar member is disposed between the first wall and the holder in the first axial direction.
The first wall includes, on the second direction side, a common fixing portion (61) that is provided on the opposite side of the positioning portion with respect to the rotating member and fixes the collar member and the holder. The developing cartridge according to claim 1, wherein:
5. The developing cartridge according to claim 4, wherein each of the positioning portion, the fixing portion, and the rotating member is disposed on a straight line that passes through a central axis of the rotating member and extends in a radial direction of rotation. .
2. The development according to claim 1, wherein the color member has a first covering portion (95) that covers the end surface of the rotating member in the second direction from the second direction side. cartridge.
The collar member includes a second covering portion (96) that is continuous with the first covering portion, faces the first wall from the second direction side, and is fixed to the fixing portion.
The developing cartridge according to claim 6, wherein the holder covers at least the second covering portion from the second direction side.
The holder is fixed by screw members (123, 124) in each of the positioning portion and the fixing portion,
The developing cartridge according to claim 7, wherein the screw member is fixed to each of the positioning portion and the fixing portion via the holder and the second covering portion.
The rotating member is a developing gear (77) arranged on the second direction side with respect to the first wall and configured to transmit a driving force from the driving mechanism to the developer carrier main body. ,
The developing cartridge according to any one of claims 1 to 8, wherein the color member covers an end of the developing gear in the second direction.
A developer supply body (52) configured to supply a developer to the developer carrier body, and configured to rotate about a second axis (A2) with respect to the housing. A developer supply body disposed on the first direction side with respect to the first wall;
A supply gear (86) configured to rotate integrally with the developer supply body about the second axis and disposed on the second direction side with respect to the first wall; ,
The at least one rotating body is configured to be rotatable with respect to the housing and is a coupling gear (85) for receiving a driving force from the outside, the coupling gear including the supply gear and the Configured to transmit driving force to each of the development gears,
The distance (D1) between the rotation axis of the coupling gear and the first axis and the distance (D2) between the rotation axis and the second axis are substantially the same length. The developing cartridge according to claim 9.
The rotating member is a rotating shaft that extends in the first axial direction, and the second direction side end portion is disposed on the second direction side of the first wall,
The developing cartridge according to claim 1, wherein the color member covers an end portion of the rotation shaft in the second direction.