JP4265584B2 - Image forming apparatus, process unit, and developing cartridge - Google Patents

Description

  The present invention relates to an electrophotographic image forming apparatus in a copying machine, a facsimile machine, a laser printer or the like, a process unit used in the image forming apparatus, and a developing cartridge.

  Conventionally, in an image forming apparatus in which a visible image representing a character or an image formed by supplying a developer to an electrostatic latent image formed on a photoreceptor is transferred to a recording medium and recorded, maintenance performance is improved. In order to improve the process unit, a process unit is used as a cartridge type so that the replacement work can be easily performed (for example, see Patent Document 1, Patent Document 2, etc.).

Such a conventional image forming apparatus is configured such that a process unit in which a developing cartridge is previously mounted on a photosensitive cartridge is mounted on the main body of the image forming apparatus.
JP-A-8-54786 JP-A-9-319285

  By the way, normally, in the conventional image forming apparatus, when the process unit is not in the correct mounting position with respect to the image forming apparatus main body, the cover of the image forming apparatus main body that is opened and closed when the process unit is attached or detached is not closed. Has been. Therefore, the user knows whether or not the process unit is in the correct mounting position with respect to the image forming apparatus main body. However, it is not known whether the developing cartridge is in the correct mounting position with respect to the photosensitive member cartridge.

For example, the process unit may be erroneously attached to the image forming apparatus main body without the developing cartridge being in the correct attachment position with respect to the photosensitive cartridge.
In such a case, there is a possibility that the rotation driving shaft provided in the image forming apparatus main body, the developing cartridge, or the like may be damaged in order to rotationally drive the developing roller included in the developing cartridge. In particular, when the image forming apparatus main body is damaged, the user cannot repair the image forming apparatus by himself, but has to request a repair from a manufacturer or the like, resulting in unnecessary cost and trouble for the repair. .

  SUMMARY An advantage of some aspects of the invention is that an image forming apparatus main body and a developing cartridge are reliably prevented from being damaged in an image forming apparatus in which a process unit having a developing cartridge is detachable. And

The invention according to claim 1, which has been made to solve such a problem, includes a photosensitive member cartridge having a photosensitive member on which an electrostatic latent image is formed, a developing roller for supplying a developer to the photosensitive member, and a photosensitive member. A development unit detachable from the cartridge, and a process unit detachable from the image forming apparatus main body,
A rotary drive shaft;
Guidance means for guiding the rotation drive shaft to the developing cartridge side so as to be connectable,
The photosensitive cartridge has an urging mechanism for pressing the developing roller against the photosensitive member,
The developing cartridge includes an actuated portion to which an urging force is applied by an urging mechanism, a developing coupling that is connected to the rotation driving shaft guided by the guide unit and transmits the rotation driving force by the rotation driving shaft to the developing roller, Have
When the developing cartridge is not normally attached to the photosensitive cartridge, the biasing mechanism is positioned in the vicinity of the developing coupling, thereby preventing the rotation drive shaft from being joined to the developing coupling.
When the developing cartridge is in a normal mounting position, the urging mechanism is configured to be able to be joined to the developing coupling by being pressed and displaced by the actuated portion. An image forming apparatus characterized by the above.

  In the image forming apparatus according to the first aspect, when the developing cartridge is not normally attached to the photosensitive member cartridge, the joining of the rotation drive shaft and the developing coupling is blocked by the biasing mechanism. However, it does not join in the first place. That is, the rotation drive shaft idles, and the rotation drive force is not transmitted to the developing cartridge. For this reason, for example, the rotation drive shaft is driven in a state where the rotation drive shaft and the development coupling are incomplete, and the rotation drive shaft, the development coupling, and the image forming apparatus and the development cartridge are damaged. Can be prevented.

  If the rotation drive shaft and the development coupling are not joined, the rotation drive force is not transmitted to the developing roller, and an image is not printed on a recording medium such as printing paper. That is, even if the image forming apparatus is caused to execute the printing process, the printing paper on which the image is not printed is discharged. Due to such a phenomenon, for example, even if a mechanism for detecting the mounting position of the developing cartridge is not particularly provided, the user can infer that the developing cartridge is not normally mounted. Therefore, it is possible to provide an image forming apparatus in which the user can easily recognize whether or not the developing cartridge is normally mounted without particularly increasing the cost. If the developing cartridge is not properly mounted, if the user easily recognizes that, the process of correctly mounting the developing cartridge is immediately performed, and the image forming apparatus and the developing cartridge are surely attached. Will be prevented from being damaged.

  In addition, in order to prevent breakage, the developing cartridge mounting position (or rotational drive shaft position) is detected and rotated when the developing cartridge is not in the normal mounting position (or the rotational drive shaft is not in the normal position). Although it is conceivable to provide a sensor for preventing the drive shaft from being driven, according to the present invention, such a sensor may not be provided. Therefore, the space for providing the sensor can be saved, and the size of the image forming apparatus can be reduced.

  The urging mechanism having a function of preventing the coupling between the developing coupling and the rotary drive shaft also has a function of pressing the developing roller against the photosensitive member. For this reason, the action of the urging mechanism not only prevents the image forming apparatus and the developing cartridge from being damaged, but also the developing roller and the photosensitive member are pressed against each other to appropriately supply the developer to the photosensitive member. In addition, it is possible to provide an image forming apparatus that performs printing with high quality.

  By the way, in the image forming apparatus according to the first aspect, as described in the second aspect, the biasing mechanism is rotatably supported at one end, and the developing cartridge is mounted on the photosensitive cartridge. A lever member that abuts against the actuated portion and a force that pushes the actuated portion toward the developing roller with respect to the lever member, so that the developing roller is moved to the photoreceptor via the lever member. And a biasing means for applying a force for pressing contact, and when the developing cartridge is not in the normal mounting position, the rotary drive shaft is joined to the developing coupling by positioning the lever member in the vicinity of the developing coupling. When the developer cartridge is in the normal mounting position, the lever member is pressed by the actuated portion and is rotationally displaced, so that the rotation drive shaft is connected to the developing coupling. It is preferably configured to be capable of bonding to.

  In the image forming apparatus according to the second aspect, the biasing means pushes the lever member supported at one end so as to be rotatable so that the developing cartridge that contacts the lever member via the lever member is acted on. A force for pressing the developing roller against the photosensitive member is applied to the portion. In brief, the developing cartridge is pushed toward the photosensitive member by the biasing means of the photosensitive member cartridge.

  Further, as the developing cartridge is mounted on the photosensitive cartridge, the lever member that comes into contact with the actuated portion of the developing cartridge rotates. Depending on the rotating position, the developing coupling and the rotation drive shaft The bonding is prevented or not prevented. Therefore, it is possible to prevent the image forming apparatus and the developing cartridge from being damaged without particularly increasing the cost with a simple configuration in which the lever member is rotated.

  Further, in the image forming apparatus according to claim 1 or 2, the urging mechanism and the developing coupling are mutually connected in a state where the developing cartridge is mounted on the photosensitive cartridge. It is preferable that they are provided at close positions.

  According to the image forming apparatus of the third aspect configured as described above, it is not necessary to increase the urging mechanism or increase the displacement range (or rotation range) of the urging mechanism. The configuration of the urging mechanism or the acted part can be made compact. Therefore, the size of the process unit and thus the image forming apparatus can be suppressed, and the cost is not particularly increased.

  By the way, in the image forming apparatus according to any one of claims 1 to 3, as described in claim 4, the image forming apparatus is perpendicular to a straight line connecting the rotation center of the developing roller and the rotation center of the developing coupling. It is conceivable that the actuated portion is provided in a region between the two straight lines passing through the rotation center of the developing roller and the straight line passing through the rotation center of the developing coupling.

  Further, in the image forming apparatus according to any one of claims 1 to 4, as described in claim 5, the developer cartridge includes a developer accommodating portion that accommodates a developer, and the developing cartridge. A stirring drive shaft that stirs the developer contained in the agent containing portion and transmits a rotational driving force to the developing roller, and the development coupling is provided at one end of the stirring drive shaft and is rotationally driven. It is preferable that the rotational driving force by the shaft is transmitted to the stirring driving shaft through the developing coupling.

  According to the image forming apparatus of the fifth aspect configured as described above, the developer is reliably stirred with sufficient torque. In this type of image forming apparatus, the developer is supplied to the outside from the developer container by the stirring force of the stirring drive shaft, and if the developer is reliably stirred with sufficient torque. The developer is reliably supplied to the developing roller. Therefore, the printing quality can be improved. Furthermore, if a developing coupling is provided at one end of the stirring drive shaft, it is not necessary to provide a new mechanism for attaching the developing coupling, and the construction of the developing cartridge can be simplified. Cost can be reduced.

According to a sixth aspect of the present invention, there is provided a photosensitive cartridge having a photosensitive member on which an electrostatic latent image is formed;
A developing cartridge that has a developing roller for supplying a developer to the photosensitive member and is detachable from the photosensitive cartridge, and
The photosensitive cartridge has an urging mechanism for pressing the developing roller against the photosensitive member,
The developing cartridge includes an actuated portion to which an urging force by an urging mechanism acts, and a developing coupling that is joined to the rotation driving shaft and transmits the rotation driving force of the rotation driving shaft to the developing roller,
When the developing cartridge is not normally attached to the photosensitive cartridge, the biasing mechanism is positioned in the vicinity of the developing coupling, thereby preventing the rotation drive shaft from being joined to the developing coupling. When the developing cartridge is in a normal mounting position, the urging mechanism is configured to be able to be joined to the developing coupling by being pressed and displaced by the actuated portion. Is a process unit characterized by

  According to the process unit of the sixth aspect, in a state where the developing cartridge is not normally attached to the photosensitive member cartridge, the joining between the rotation drive shaft and the developing coupling is blocked by the biasing mechanism, However, it does not join in the first place. That is, the rotation drive shaft idles, and the rotation drive force is not transmitted to the developing cartridge. For this reason, for example, it is possible to prevent the rotation drive shaft and the development coupling from being incompletely joined, and the rotation drive shaft, the development coupling, and the development cartridge and the process unit from being damaged.

  Further, if the rotation drive shaft and the development coupling are not joined, the rotation drive force is not transmitted to the developing roller, and the image forming apparatus using this process unit does not print an image on a recording medium such as printing paper. It will be. That is, even if the image forming apparatus is caused to execute the printing process, the printing paper on which the image is not printed is discharged. Due to such a phenomenon, for example, even if a mechanism for detecting the mounting position of the developing cartridge is not particularly provided, the user can infer that the developing cartridge is not normally mounted.

  Therefore, the user can easily recognize whether or not the developing cartridge is normally mounted without particularly increasing the cost. If the developer cartridge is not properly mounted and it is easily recognized by the user, a process of correctly mounting the developer cartridge is immediately performed, and the developer cartridge and the process unit are surely installed. Damage is prevented.

  In addition, in order to prevent breakage, the developing cartridge mounting position (or rotational drive shaft position) is detected and rotated when the developing cartridge is not in the normal mounting position (or the rotational drive shaft is not in the normal position). Although it is conceivable to provide the image forming apparatus with a sensor that prevents the drive shaft from being driven, according to the present invention, such a sensor may not be provided. Therefore, it is possible to provide a process unit that saves a space for providing the sensor and suppresses the size of the image forming apparatus.

  The urging mechanism having a function of preventing the coupling between the developing coupling and the rotary drive shaft also has a function of pressing the developing roller against the photosensitive member. For this reason, the action of the urging mechanism not only prevents the development cartridge and the process unit from being damaged, but also the developer roller and the photosensitive member come into pressure contact with each other so that the developer is appropriately supplied to the photosensitive member. . If the developer is appropriately supplied to the photoconductor, it is possible to cause the image forming apparatus using the process unit to perform reliable and high-quality printing.

  Further, in the process unit according to the sixth aspect, as described in the seventh aspect, the biasing mechanism is rotatably supported at one end, and when the developing cartridge is mounted on the photosensitive cartridge. A lever member that abuts on the actuated part, and a force that pushes the actuated part in the direction of the developing roller to the lever member, thereby pressing the developing roller against the photoreceptor via the lever member And a biasing means for applying a force for contact, and when the developing cartridge is not in the normal mounting position, the rotary drive shaft is joined to the developing coupling by positioning the lever member in the vicinity of the developing coupling. When the developer cartridge is in the normal mounting position, the lever member is pressed by the actuated portion and is rotationally displaced, so that the rotational drive shaft is connected to the developing coupling. Is configured to become possible to bonding, it is preferred.

  In the process unit according to claim 7, the urging means pushes the lever member that is rotatably supported at one end, so that the affected portion of the developing cartridge that contacts the lever member via the lever member In addition, a force for pressing the developing roller against the photosensitive member is applied. In brief, the developing cartridge is pushed toward the photosensitive member by the biasing means of the photosensitive member cartridge.

  Further, as the developing cartridge is mounted on the photosensitive cartridge, the lever member that comes into contact with the actuated portion of the developing cartridge rotates. Depending on the rotating position, the developing coupling and the rotation drive shaft The bonding is prevented or not prevented. Therefore, the development cartridge and the process unit can be prevented from being damaged without particularly increasing the cost with a simple configuration in which the lever member is rotated.

  Further, in the process unit according to claim 6 or 7, as described in claim 8, the urging mechanism and the developing coupling are close to each other in a state where the developing cartridge is mounted on the photosensitive cartridge. It is preferable to be provided at a position where

  According to the process unit of claim 8 configured in this way, it is not necessary to increase the biasing mechanism or increase the displacement range (or rotation range) of the biasing mechanism. The configuration of the urging mechanism or the actuated part can be made compact. Therefore, the size of the photosensitive member cartridge, the developing cartridge, and the process unit can be suppressed, and the cost is not particularly increased.

  By the way, in the process unit according to any one of claims 6 to 8, as described in claim 9, the process unit is perpendicular to a straight line connecting the rotation center of the developing roller and the rotation center of the development coupling. It is conceivable that the actuated portion is provided in a region between two straight lines that pass through the rotation center of the developing roller and a straight line that passes through the rotation center of the developing coupling.

  Furthermore, in the process unit according to any one of claims 6 to 9, as described in claim 10, the developer cartridge includes a developer accommodating portion that accommodates a developer, and the developer. An agitation drive shaft that agitates the developer contained in the accommodation unit and transmits a rotational driving force to the developing roller, and the development coupling is provided at one end of the agitation drive shaft. It is preferable that the rotational driving force is transmitted to the stirring drive shaft through the developing coupling.

  According to the process unit of the tenth aspect configured as described above, the developer is reliably stirred with a sufficient torque. Further, in this type of process unit, the developer is supplied from the developer container by the stirring force of the stirring drive shaft, and if the developer is reliably stirred with sufficient torque. The developer is reliably supplied to the developing roller. Therefore, printing quality can be improved in an image forming apparatus using this process unit. Furthermore, if a developing coupling is provided at one end of the stirring drive shaft, it is not necessary to provide a new mechanism for attaching the developing coupling, and the construction of the developing cartridge can be simplified. Cost can be reduced.

The invention according to claim 11 is a developing roller for supplying a developer to a photoconductor on which an electrostatic latent image is formed;
A housing that supports the developing roller and is detachable from the photosensitive cartridge having the photosensitive member;
A developing coupling that is provided in the housing and is connected to the rotational drive shaft to transmit the rotational driving force of the rotational drive shaft to the developing roller;
An actuated portion provided in a housing and subjected to an urging force by an urging mechanism provided in the photosensitive member cartridge in order to press and contact the developing roller to the photosensitive member;
When the casing is normally mounted on the photosensitive cartridge, the actuated portion presses the urging mechanism and displaces the urging mechanism so as not to prevent the rotation drive shaft from joining the developing coupling. The developing cartridge is provided at a position.

  In the developing cartridge according to the eleventh aspect, when the casing is normally attached to the photosensitive cartridge, the actuated portion presses and displaces the biasing mechanism, so that the rotation drive shaft and the developing coupling are separated. Joining is not prevented by the biasing mechanism, and if the housing is not properly attached to the photosensitive cartridge, the actuated part does not displace the biasing mechanism. Is blocked by the biasing mechanism. That is, the rotation drive shaft idles, and the rotation drive force is not transmitted to the developing cartridge. Therefore, when the developing cartridge is not normally attached to the photosensitive cartridge and the process unit including both is attached to the image forming apparatus, for example, the rotation drive shaft and the developing coupling are not joined. As a result, it is possible to prevent the rotation drive shaft, the development coupling, and the development cartridge from being damaged.

  In addition, since the rotational driving force is not transmitted to the developing roller unless the rotational driving shaft and the development coupling are joined, in such a case, the image forming apparatus does not print an image on a recording medium such as printing paper. It becomes. That is, even if the image forming apparatus is caused to execute the printing process, the printing paper on which the image is not printed is discharged. Due to such a phenomenon, for example, even if a mechanism for detecting the mounting position of the developing cartridge is not particularly provided, the user can infer that the developing cartridge is not normally mounted. Therefore, the user can easily recognize whether or not the developing cartridge is normally mounted without particularly increasing the cost. If the developer cartridge is not properly installed and it is easily recognized by the user, the developer cartridge can be installed correctly, and the development cartridge can be reliably prevented from being damaged. Will come to be.

  In addition, in order to prevent breakage, the developing cartridge mounting position (or rotational drive shaft position) is detected and rotated when the developing cartridge is not in the normal mounting position (or the rotational drive shaft is not in the normal position). Although it is conceivable to provide the image forming apparatus with a sensor that prevents the drive shaft from being driven, according to the present invention, such a sensor may not be provided. Therefore, it is possible to provide a developing cartridge that saves space for providing the sensor and can suppress the size of the image forming apparatus.

  The developing cartridge is also configured to receive an action of an urging mechanism so that the developing roller is pressed against the photosensitive member. Therefore, in a state where the developing cartridge is normally attached to the photosensitive member cartridge, the developing roller appropriately supplies the developer to the photosensitive member, and the process unit including the developing cartridge and the photosensitive member cartridge is used. The image forming apparatus can perform reliable and high-quality printing.

  In the developing cartridge according to the eleventh aspect, as described in the twelfth aspect, the biasing mechanism is rotatably supported at one end and is mounted when the developing cartridge is attached to the photosensitive cartridge. A lever member that abuts on the actuated part, and a force that pushes the actuated part in the direction of the developing roller to the lever member, thereby pressing the developing roller against the photoreceptor via the lever member And an urging means for applying a force for contact, and when the developing cartridge is not normally attached to the photosensitive member, the developing coupling is located in the vicinity of the lever member. As a result, the lever member prevents the rotation drive shaft from joining the developing coupling, and when the developing cartridge is in the normal mounting position, the operated portion Pressure by rotational displacements, and is configured such that the junction of the rotary drive shaft of the development coupling allows, it is preferable.

  The developing cartridge according to claim 12, wherein the biasing means presses a lever member that is rotatably supported at one end thereof, so that the affected portion of the developing cartridge that comes into contact with the lever member via the lever member is pressed. In addition, a force for pressing the developing roller against the photosensitive member is applied. In brief, the developing cartridge is pushed toward the photosensitive member by the biasing means of the photosensitive member cartridge.

  Further, as the developing cartridge is mounted on the photosensitive cartridge, the operated portion of the developing cartridge rotates the lever member that comes into contact with the operated portion. Depending on the rotation position of the lever member, Joining between the development coupling and the rotary drive shaft is blocked or not blocked. In other words, the developing cartridge can be prevented from being damaged with a simple configuration in which the lever member is pivoted without particularly increasing the cost.

  In the developing cartridge according to claim 11 or 12, as described in claim 13, the developing coupling is close to the urging mechanism in a state where the developing cartridge is mounted on the photosensitive cartridge. It is preferable to be provided at the position.

  According to the developing cartridge of the thirteenth aspect thus configured, it is not necessary to particularly increase the size of the actuated portion. Therefore, the size of the developing cartridge can be suppressed, and the cost is not particularly increased.

  By the way, in the developing cartridge according to any one of claims 11 to 13, as described in claim 14, the developing cartridge is perpendicular to a straight line connecting the rotation center of the developing roller and the rotation center of the developing coupling. It is conceivable that the actuated portion is provided in a region between two straight lines that pass through the rotation center of the developing roller and a straight line that passes through the rotation center of the developing coupling.

  Further, in the developing cartridge according to any one of claims 11 to 14, as described in claim 15, the developing cartridge includes a developer accommodating portion that accommodates a developer, and the developing cartridge. A stirring drive shaft that stirs the developer contained in the agent containing portion and transmits a rotational driving force to the developing roller, and the development coupling is provided at one end of the stirring drive shaft and is rotationally driven. It is preferable that the rotational driving force by the shaft is transmitted to the stirring driving shaft through the developing coupling.

  According to the developing cartridge of the fifteenth aspect configured as described above, the developer is reliably stirred with a sufficient torque. In this type of developing cartridge, the developer is supplied to the outside from the developer accommodating portion by the stirring force of the stirring drive shaft, and if the developer is reliably stirred with sufficient torque. The developer is reliably supplied to the developing roller. Therefore, printing quality can be improved in an image forming apparatus using the developing cartridge. Furthermore, if a developing coupling is provided at one end of the stirring drive shaft, it is not necessary to provide a new mechanism for attaching the developing coupling, and the construction of the developing cartridge can be simplified. Cost can be reduced.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[Embodiment 1]
1 and 2 are schematic side sectional views of a laser printer 1 as an image forming apparatus. This laser printer 1 includes a feeder unit 4 for feeding a paper P on which an image is formed, an image forming unit 5 for forming an image on the fed paper P, and the like in a main body casing 2. ing. The image forming unit 5 further includes a scanner unit 19, a process unit 20, a fixing unit 21, and the like. Note that the process unit 20 is configured to be detachable from the main casing 2, and FIG. 2 shows a state in which the process unit 20 is detached from the main casing 2 (or a state before mounting).

  As shown in FIGS. 1 and 2, in the main body casing 2 of the laser printer 1, an attachment / detachment opening 6 for attaching / detaching the process unit 20 is formed on one side wall (right side in the drawing). A front cover 7 for opening and closing the detachable opening 6 is provided. The front cover 7 is rotatably supported by a cover shaft (not shown) inserted through the lower end portion thereof, and can be opened and closed with the cover shaft as a fulcrum.

  In the following, in the laser printer 1 and the process unit 20, the side on which the front cover 7 is provided (upstream side in the mounting direction of the process unit 20) is referred to as “front side”, and the opposite side (downstream side in the mounting direction of the process unit 20). Is “rear side”. Also, the front side in FIG. 1 and FIG. 2 is referred to as “left side” and the back side in FIG. 2 is referred to as “right side”.

  By the way, the feeder unit 4 is provided at the bottom of the main casing 2, and is detachably mounted on the sheet feeding tray 9, the sheet feeding roller 10 disposed above the front end of the sheet feeding tray 9, and the separation unit. A pad 11, a pickup roller 12 provided on the rear side of the paper feed roller 10, a pinch roller 13 arranged to face the paper feed roller 10 below the front side of the paper feed roller 10, A pair of upper and lower registration rollers 14 (also see FIGS. 4 and 5) provided on the upper rear side are provided.

  Inside the paper feed tray 9, there is provided a paper pressing plate 15 on which the paper P can be stacked. The sheet pressing plate 15 is supported at the rear end so as to be swingable, so that the front end can be moved in the vertical direction.

  A lever 17 for lifting the front end portion of the paper pressing plate 15 upward is provided at the front end portion of the paper feed tray 9. The lever 17 is formed in a substantially L-shaped cross section so as to go downward from the front portion of the paper pressing plate 15, and an upper end portion thereof is connected to a lever shaft 18 provided at the front end portion of the paper feed tray 9. The rear end portion of the paper pressing plate 15 is in contact with the lower surface near the front end portion. Accordingly, when a clockwise rotational driving force in the drawing is input to the lever shaft 18, the lever 17 rotates about the lever shaft 18, and the rear end portion of the lever 17 lifts the front end portion of the paper pressing plate 15.

  When the front end of the paper pressing plate 15 is lifted, the uppermost paper P on the paper pressing plate 15 is pressed by the pickup roller 12. Then, the conveyance of the paper P is started between the paper feed roller 10 and the separation pad 11 by the rotation of the pickup roller 12.

  On the other hand, when the paper feed tray 9 is detached from the main casing 2, the front end of the paper pressing plate 15 moves downward due to its own weight, and is in a state along the bottom surface of the paper feed tray 9. In this state, the paper P can be stacked on the paper pressing plate 15.

  Note that the sheet P that has started to be conveyed between the sheet feeding roller 10 and the separation pad 11 by the pickup roller 12 is sandwiched between the sheet feeding roller 10 and the separation pad 11, and then the sheet feeding roller 10. , The paper is reliably fed and fed one by one.

  Further, the sheet P is transferred to a transfer position of the image forming unit 5 (between a photosensitive drum 92 and a transfer roller 94, which will be described later, by a registration roller 14 including a pair of upper and lower rollers. The toner image carried on the body drum 92 is conveyed to a position where the toner image is transferred onto the paper P.

As described above, the image forming unit 5 includes the scanner unit 19, the process unit 20, the fixing unit 21, and the like.
The scanner unit 19 is provided above the main casing 2 and includes a laser light source (not shown), a polygon mirror 22 that is rotationally driven, an fθ lens 23, a reflecting mirror 24, a lens 25, a lower reflecting mirror 26, and the like. The laser beam based on the image data emitted from the laser light source is deflected by the polygon mirror 22 and passes through the fθ lens 23, the optical path is turned back by the reflecting mirror 24, and after passing through the lens 25, the lower reflecting mirror 26 Further, the optical path is bent downward, and is irradiated onto the surface of a photosensitive drum 92 (to be described later) of the process unit 20.

  The process unit 20 is detachably attached to the main casing 2 as described above under the scanner unit 19 (see FIG. 1). The process unit 20 includes a photosensitive cartridge 27 and a developing cartridge 28 that is detachably attached to the photosensitive cartridge 27. The developing cartridge 28 can be attached to and detached from the main body casing 2 integrally with the photosensitive cartridge 27. Further, only the developing cartridge 28 can be attached to and detached from the main casing 2 with the photosensitive cartridge 27 mounted on the main casing 2. Details of the developing cartridge 28 and the photosensitive member cartridge 27 will be described later.

  The fixing unit 21 is provided on the rear side of the process unit 20 and includes a fixing frame 182, and includes a heating roller 183 and a pressure roller 184 in the fixing frame 182.

  Although details of the heating roller 183 and the pressure roller 184 are not shown, first, the heating roller 183 includes a metal base tube and a halogen lamp provided in the metal base tube. The heating roller 183 is rotationally driven by a driving force from a motor.

  The pressure roller 184 is disposed opposite the heating roller 183 so as to press the heating roller 183. The pressure roller 184 includes a metallic roller shaft and a roller made of a rubber material that covers the periphery of the roller shaft, and is driven in accordance with the rotational drive of the heating roller 183.

  The fixing unit 21 heat-fixes the toner as a developer transferred onto the paper P at the transfer position onto the paper P while the paper P passes between the heating roller 183 and the pressure roller 184. The paper P on which the toner is fixed is conveyed to a paper discharge path 185 that extends in the vertical direction toward the upper surface of the main casing 2. The paper P conveyed to the paper discharge path 185 is discharged onto a paper discharge tray 187 formed on the upper surface of the main casing 2 by a paper discharge roller 186 provided on the upper side thereof.

  By the way, as shown in FIG. 3, the laser printer 1 has a coupling member 73 connected to the left frame 167 so as to be movable forward and backward, and a mechanism for moving the coupling member 73 forward and backward. Arm 291. The coupling member 73 is provided to join a developing coupling 66 (described later) of the developing cartridge 28 (see FIG. 11) and transmit a rotational driving force to the developing coupling 66. This corresponds to the rotational drive shaft of the invention. The arm 291 corresponds to a guide means. In FIG. 3A, the coupling member 73 is in the advanced state, and in FIG. 3B, the coupling member 73 is in the retracted state.

The arm 291 is integrally provided with an arm portion 292 extending along the front-rear direction and a cam portion 293 provided at the rear end portion of the arm portion 292.
A long hole extending in the front-rear direction through which the coupling member 73 is inserted is formed in the cam portion 293, and an axial direction (in the rotational axis direction of the coupling member 73) around the rear end portion of the long hole. There is a thick material portion 294 that is thickly formed. A thin material portion 295 that is thin in the width direction is provided around the front end portion of the long hole.

  The arm 291 is supported so as to be movable in the front-rear direction along the left frame 167 in a state where the coupling member 73 is inserted through the long hole at the rear end. The arm 291 is provided so as to move in the front-rear direction in conjunction with opening and closing of the front cover 7 (see FIGS. 1 and 2).

  The coupling member 73 is disposed so as to face a developing coupling 66 (to be described later) in the process unit 20 attached to the main casing 2 in the axial direction. The coupling member 73 receives a rotational driving force from a motor (not shown) provided in the main body casing 2. Further, the coupling member 73 is constantly urged toward the inner side in the axial direction (from the left side to the right side in FIG. 3) by an urging spring (not shown).

  When the front cover 7 is opened when the process unit 20 is attached to and detached from the main casing 2, the arm 291 moves forward in conjunction with the opening of the front cover 7, as shown in FIG. In addition, the thick member 294 engages with the coupling member 73. Then, the coupling member 73 moves backward against the biasing force of the biasing spring.

  When the front cover 7 is closed when the process unit 20 is attached to and detached from the main casing 2, the arm 291 moves rearward in conjunction with the closing of the front cover 7 and is shown in FIG. As described above, the thin member 295 engages with the coupling member 73. Then, the coupling member 73 is advanced by the urging force of the urging spring and is coupled to the developing coupling 66 of the process unit 20 so as not to rotate relative to each other. As a result, the driving force from the coupling member 73 is transmitted to the process unit 20 via the development coupling 66.

Here, the configurations of the photosensitive member cartridge 27 and the developing cartridge 28 will be described.
First, the photosensitive cartridge 27 will be described with reference to FIGS. 4 and 5 are diagrams showing the process unit 20. In particular, FIG. 5 shows a state in which the developing cartridge 28 is being attached to the photosensitive cartridge 27 (or incompletely attached state). Represents.

  The photosensitive cartridge 27 includes a drum-side casing 91 made of a resin material, and further includes a photosensitive drum 92, a scorotron charger 93, a transfer roller 94, a cleaning brush 95, and the like in the drum-side casing 91. ing.

  The photosensitive drum 92 is disposed in the drum housing portion 102. The photosensitive drum 92 has a cylindrical shape, the outermost layer is formed of a positively charged photosensitive layer made of polycarbonate or the like, and the longitudinal axis of the drum body 124 at the axial center of the drum body 124. And a metal drum shaft 125 extending in the direction. The drum shaft 125 is supported so as not to rotate with respect to the drum-side housing 91. The drum body 124 is supported so as to be rotatable with respect to the drum shaft 125.

  The scorotron charger 93 is disposed in the drum housing portion 102 and is supported by the charging support portion 122 obliquely above the rear side of the photosensitive drum 92 so as not to come into contact with the photosensitive drum 92. It arrange | positions so that it may oppose. The scorotron charger 93 generates corona discharge by applying a grid voltage and a discharge voltage to uniformly positively charge the surface of the photosensitive drum 92.

  The surface of the photosensitive drum 92 is uniformly positively charged by the scorotron charger 93 as the photosensitive drum 92 rotates, and then exposed by high-speed scanning of the laser beam from the scanner unit 19. . Then, an electrostatic latent image representing an image to be formed on the paper P is formed on the surface of the photosensitive drum 92. The toner is supplied to the photosensitive drum 92 via the developing roller 32, and the electrostatic latent image is visualized.

  The transfer roller 94 is disposed below the photosensitive drum 92 in the drum housing portion 102. The transfer roller 94 includes a metal transfer roller shaft 133 and a rubber roller 134 made of an ion conductive rubber material covering the periphery of the transfer roller shaft 133. The transfer roller 94 is disposed so as to face the photoconductive drum 92, and the sheet P conveyed between the transfer roller 94 and the photoconductive drum 92 is visible on the photoconductive drum 92. The image is transferred.

  The cleaning brush 95 is composed of a large number of brush hairs, is supported by the brush support portion 123 on the rear side of the photosensitive drum 92, and is arranged so that the brush hair contacts the surface of the photosensitive drum 92. Then, after the visible image on the photosensitive drum 92 is transferred to the paper P, excess toner adhering to the surface of the photosensitive drum 92 is removed by the cleaning brush 95.

  Further, an urging mechanism 60 for pushing the developing cartridge 28 toward the photosensitive drum 92 is provided on the inner surface of the left side wall 30c of the photosensitive cartridge 27. The urging force generated by the urging mechanism 60 acts on a later-described operated portion 67 of the developing cartridge 28, and thereby the developing cartridge 28 is pushed toward the photosensitive drum 92 of the photosensitive cartridge 27. Then, the developing roller 32 is pressed into contact with the photosensitive drum 92.

Next, the configuration of the developing cartridge 28 will be described with reference to FIGS. 6 to 8 are a plan view, a right side view, and a left side view of the developing cartridge 28, respectively.
The developing cartridge 28 includes a developing side casing 29 as a casing, and within the developing side casing 29, as shown in FIGS. 7 and 8, a supply roller 31, a developing roller 32, an agitator 70, and a layer A thickness regulating blade 33 is provided. Further, an actuated portion 67 on which the urging force of the urging mechanism 60 (see FIGS. 1 and 2) of the photosensitive cartridge 27 acts is provided.

  The development side housing 29 is made of, for example, a resin material such as polystyrene, and has a box shape with an opening on the rear side (see FIG. 6), and includes a lower frame 34 (see FIGS. 7 and 8) and an upper frame 35. Yes. In addition, the developing housing 29 is provided with a toner storage chamber 30.

  The lower frame 34 includes a left side wall 38 and a right side wall 39 arranged to face each other with a gap in the width direction (a direction orthogonal to both the front-rear direction and the up-down direction, the same applies hereinafter), and the left side wall 38 and A lower wall 40 and an upper wall 41 which are connected to the right side wall 39 and are arranged vertically, and an upper front wall 42 provided at a front end portion of the upper wall 41 are integrally provided.

  The lower wall 40 further includes a rear lower wall portion 43 for defining a developing chamber (not shown), and a front lower wall portion formed continuously from the rear lower wall portion 43 and having a substantially arcuate cross section. 44 are integrally provided. The lower wall 40 is provided so as to be sandwiched between the left side wall 38 and the right side wall 39.

  A positioning portion 84 for positioning the developing cartridge 28 with respect to the photosensitive cartridge 27 is provided at the deepest portion of the front lower wall portion 44. The positioning portions 84 are formed in a convex shape downward, and are provided at two intervals in the width direction so as to come into contact with a protrusion (not shown) of the photosensitive cartridge 27.

  The upper wall 41 has a flat plate shape wider than the facing distance between the left side wall 38 and the right side wall 39 (see FIG. 6), and is laid between the upper end edges of the left side wall 38 and the right side wall 39. A portion of the upper wall 41 whose front side extends forward is an upper wall extension 50.

The front wall edge of the upper wall extension 50 is provided with an upper front wall 42 that is formed in a plate shape and is bent in a substantially vertical direction downward from the front edge.
The upper frame 35 is provided so as to cover the lower frame 34.

  By the way, as shown in FIG. 8, a gear mechanism 45 is provided on the left side wall 38 of the developing cartridge 28. The gear mechanism portion 45 is provided with a gear cover 77. The gear cover 77 includes a developing coupling 66 on the outer side thereof that is joined to a coupling member 73 (see FIG. 3) of the laser printer 1. Then, when the developing coupling 66 is joined to the coupling member 73, the rotational driving force of the coupling member 73 is transmitted to the developing coupling 66. The gear cover 77 holds, on its inner side, various gears for rotating the developing roller 32, the supply roller 31, or the agitator 70, and the rotational driving force of the developing coupling 66 is the developing roller. 32, the supply roller 31, and the agitator 70.

  Although not shown, the supply roller 31 includes a metal supply roller shaft and a sponge roller made of a conductive foam material covering the supply roller shaft. Note that the left shaft end of the supply roller shaft is provided so as to protrude from the left wall 38.

  The developing roller 32 is provided so as to be in pressure contact with the supply roller 31 and to have a rear end portion partially exposed rearward from the developing side housing 29. The developing roller 32 includes a metal developing roller shaft 64 and a rubber roller 65 made of a conductive rubber material that covers the periphery of the developing roller shaft 64. It should be noted that both end portions of the developing roller shaft 64 are provided so as to protrude from the left side wall 38 and the right side wall 39.

  The agitator 70 is driven to rotate about the stirring shaft 71a, and stirs the toner in the toner storage chamber 30 provided in the developing-side housing 29 in a downward convex curved shape. The toner in the toner storage chamber 30 is agitated by the agitator 70 and discharged from the toner storage chamber 30, and is then carried on the outer peripheral surface of the developing roller 32 via the supply roller 31.

  Although not shown, the layer thickness regulating blade 33 includes a blade made of a metal leaf spring material and a pressure contact portion made of an insulating silicone rubber having a semicircular cross section provided at the lower end portion of the blade. ing. The pressing portion is pressed against the surface of the rubber roller 65 of the developing roller 32 by the elastic force of the blade. Thereby, the layer thickness of the toner carried on the surface of the rubber roller 65 is made uniform.

Next, the operation of mounting the developing cartridge 28 on the photosensitive cartridge 27 will be described with reference to FIGS. 4 and 5 and FIGS.
First, in FIGS. 4 and 5, when the developing cartridge 28 is mounted to the photosensitive cartridge 27, the developing roller shaft 64 of the developing roller 32 protruding from the developing side housing 29 in the developing cartridge 28 is moved to the photosensitive member. The cartridge is brought into contact with the guide 36 of the cartridge 27. Then, along the guide 36, the developing cartridge 28 is guided to the photosensitive drum 92 side via the developing roller shaft 64, and the developing roller shaft 64 abuts on the engaging portion 36a of the photosensitive cartridge and is locked. Is done. Thereafter, when the front side (upper wall extension portion 50) of the developing cartridge 28 is lowered downward, the positioning portion 84 (see FIGS. 7 and 8) of the developing cartridge 28 described above finally becomes the photosensitive member cartridge 27. The developing cartridge 28 is mounted at the mounting position with respect to the photosensitive cartridge 27. It should be noted that when the front side (upper wall extension 50) of the developing cartridge 28 is lowered downward, the biasing mechanism 60 of the photosensitive cartridge 27 and the operated portion 67 of the developing cartridge 28 come into contact with each other. Here, the effect | action is demonstrated using FIGS. 9-12.

  As shown in FIGS. 9 and 10, the urging mechanism 60 provided on the inner surface of the left side wall 30c (see FIGS. 4 and 5) of the photoconductor cartridge 27 includes a rotation support shaft 61a and the rotation support. The rotating member 61 is supported so as to be rotatable about a shaft 61a, and a coil spring 62 is provided as a biasing means for biasing the rotating member 61 so as to press it against one side. The coil spring 62 rotates in the direction in which the rotating member 61 rotates toward the photosensitive drum 92, that is, in the direction in which the rotating member 61 rotates counterclockwise about the rotation support shaft 61a. 61 is energized. When the developing cartridge 28 is not attached to the photosensitive cartridge 27, the contact portion 61b of the rotating member 61 contacts a contact member (not shown) of the photosensitive cartridge 27, and the rotating member is at the contact position. The rotation of 61 is prevented.

  When the developing cartridge 28 is lowered with the developing roller shaft 64 locked to the locking portion 36a, the actuated portion 67 of the developing cartridge 28 is biased at a predetermined position as described above. It contacts the rotating member 61 of the mechanism 60 (solid line in FIG. 10). When the developing cartridge 28 is further lowered, the rotating member 61 of the urging mechanism 60 rotates clockwise so as to be pushed away by the actuated portion 67 as indicated by the wavy line in FIG. . When the developing cartridge 28 is not yet in the mounting position with respect to the photosensitive cartridge 27, that is, when the mounting is incomplete, the rotating member 61 of the biasing mechanism 60 covers a part of the developing coupling 66. Will be located. As described above, the development coupling 66 is joined to the coupling member 73 (see FIG. 3 or FIGS. 11 and 12) and is rotationally driven. In this way, the development cartridge 28 is not completely mounted. If so, the rotation member 61 prevents the development coupling 66 and the coupling member 73 from being joined. FIG. 12 is a plan view showing a state where the rotation member 61 prevents the development coupling 66 and the coupling member 73 from being joined. FIG. 11 is a plan view showing a state in which the developing coupling 66 and the coupling member 73 are joined.

  Here, the reason why the coupling between the development coupling 66 and the coupling member 73 is blocked (or not blocked) as described above will be described with reference to FIGS. FIG. 13 shows a state where the process unit 20 is not attached to the laser printer 1, and FIG. 14 shows a state where the process unit 20 is attached to the laser printer 1.

  First, in FIG. 13, the developing cartridge 28 is not mounted in the correct mounting position with respect to the photosensitive cartridge 27. When the developing cartridge 28 is mounted at the correct mounting position with respect to the photosensitive member cartridge 27, the developing cartridge 28 and the photosensitive member cartridge 27 are brought into close contact with each other as shown in FIG. Even when the developing cartridge 28 is not mounted at the correct mounting position with respect to the photosensitive cartridge 27, the process unit 20 may be mounted on the laser printer 1 as shown in FIG. . For this reason, the inventor of the present application has a configuration like the laser printer 1.

  That is, according to the present laser printer 1, even if the process unit 20 is mounted on the laser printer 1 while the developing cartridge 28 is not in the mounting position with respect to the photosensitive cartridge 27 as shown in FIGS. The coupling member 73 and the development coupling 66 are not joined in the first place. Therefore, when the developing cartridge 28 is not in the mounting position with respect to the photoreceptor cartridge 27, for example, the coupling member 73 is rotationally driven in a state in which the developing coupling 66 and the coupling member 73 are incompletely connected, and the coupling member 73 and the development coupling 66 are prevented from being damaged, and further, the laser printer 1 and the development cartridge 28 are prevented from being damaged.

  In addition, when the development coupling 66 and the coupling member 73 are not joined, the image is not transferred to the paper P, so that the user is not in the mounting position with respect to the photosensitive cartridge 27 at that time. It is possible to easily guess and perform appropriate processing.

  Further, in order to prevent breakage, the position of the developing cartridge 28, the developing coupling 66, or the coupling member 73 is detected, and if the developing cartridge is not in the mounting position with respect to the photosensitive cartridge 27, the coupling member 73 is rotated. Although it is conceivable to provide a sensor or the like so as not to be driven, according to the laser printer 1, it is not necessary to provide such a sensor, and a space for providing the sensor can be saved. Therefore, the overall size of the laser printer 1 can be suppressed.

  Then, when the developing cartridge 28 is mounted at the mounting position with respect to the photosensitive cartridge 27, as shown in FIG. 9, the rotating member 61 is pushed by the actuated portion 67, so that the developing coupling 66 is not covered. Rotate until Then, as shown in FIG. 11, the development coupling 66 and the coupling member 73 can be joined.

  By the way, in a state where the operated part 67 is in contact with the rotating member 61, a biasing force by the coil spring 62 acts on the operated part 67 through the rotating member 61. That is, a force that pushes the developing roller 32 toward the photosensitive drum 92 is applied to the operated portion 67. More specifically, the developing cartridge 28 is pushed toward the photosensitive drum 92 via the actuated portion 67. By such an action, the developing roller 32 and the photosensitive drum 92 are in press contact.

  As described above, the urging mechanism 60 of the photosensitive member cartridge 27 has a function of blocking or not blocking the bonding between the developing coupling 66 and the coupling member 73 and developing via the actuated portion 67. It also has a function of pressing the roller 32 and the photosensitive drum 92. Therefore, the former function not only prevents damage, but also ensures that the toner is supplied to the photosensitive drum 92 by the latter function. Furthermore, since it is not necessary to provide a separate mechanism, the configuration of the process unit, and thus the image forming apparatus, can be simplified.

  By the way, in the present embodiment, the developing coupling 66, the urging mechanism 60, and the actuated portion 67 are close to each other in a state where the developing cartridge 28 is mounted at the mounting position with respect to the photosensitive cartridge 27. Provided (see FIG. 9). According to such a configuration, it is not necessary to increase the size of the actuated portion 67 or increase the rotation range of the rotation member 61 in the urging mechanism 60. There is no increase.

Further, as shown in FIG. 9, the actuated portion 67 is two straight lines perpendicular to a straight line L1 connecting the rotation center of the developing roller 32 and the rotation center of the development coupling 66, and the rotation center of the developing roller 32. Is provided in a region between a straight line L2 passing through and a straight line L3 passing through the rotation center of the developing coupling 66.
[Embodiment 2]
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 15 is a left side view of the developing cartridge 28 of the second embodiment.

  As shown in FIG. 15, in the second embodiment, in the developing cartridge 28, the developing coupling 66 is provided at the shaft end of the stirring shaft 71a (see FIG. 8). Further, as the developing coupling 66 is provided at the shaft end of the stirring shaft 71a, the operated portion 67 is provided closer to the stirring shaft 71a than the first embodiment (that is, the front side of the developing cartridge 28). ing. Further, although not shown, in the photosensitive member cartridge 27, the urging mechanism 60 is also provided on the front side of the first embodiment.

  According to such a configuration of the second embodiment, the agitator 70 is also rotationally driven as the developing coupling 66 is rotationally driven, and the toner in the toner storage chamber 30 is reliably agitated with sufficient torque. At the same time, the toner is reliably supplied from the toner storage chamber 30. Therefore, the printing quality can be improved.

Further, it is not necessary to provide a new shaft for attaching the development coupling 66, so that the configuration can be simplified and the cost can be reduced.
Further, when the developing coupling 66 is provided on the front side of the developing cartridge 28 and the actuated portion 67 is also provided on the front side of the developing cartridge 28, the actuated portion 67 is provided on the rear side of the developing cartridge 28. In comparison, the developing roller 32 and the photosensitive drum 92 are more stably pressed and contacted. Further, if the development coupling 66 is provided on the front side, assembly and maintenance are facilitated.

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various form can be taken within the technical scope of this invention.
For example, in the above-described embodiment, the rotation member 61 is positioned so as to cover the development coupling 66 so that the joint between the development coupling 66 and the coupling member 73 is prevented. It is good also as a structure which 73 advance operation itself is blocked | prevented. In this case, for example, it is conceivable that the rotation member 61 is positioned so as to cover the coupling member 73, or the operation of the arm 291 for moving the coupling member 73 forward is prevented.

It is a schematic sectional side view of a laser printer (the 1). It is a schematic sectional side view of a laser printer (the 2). It is explanatory drawing explaining operation | movement of the coupling member of a laser printer. It is the schematic of a process unit (the 1). It is the schematic of a process unit (the 2). FIG. 3 is a plan view of a developing cartridge. FIG. 4 is a right side view of the developing cartridge. FIG. 6 is a left side view of the developing cartridge. It is explanatory drawing explaining the mounting operation in a process unit (the 1). It is explanatory drawing explaining the mounting operation in a process unit (the 2). It is explanatory drawing explaining the mounting operation in a process unit (the 3). It is explanatory drawing explaining the mounting operation in a process unit (the 4). It is a schematic sectional side view of a laser printer (the 3). It is a schematic sectional side view of a laser printer (the 4). FIG. 10 is a left side view of a developing cartridge according to a second embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Laser printer, 2 ... Main body casing, 4 ... Feeder part, 5 ... Image formation part, 6 ... Removable opening part, 7 ... Front cover, 9 ... Paper feed tray, 10 ... Paper feed roller, 11 ... Separation pad, 12 DESCRIPTION OF SYMBOLS ... Pick-up roller, 13 ... Pinch roller, 14 ... Registration roller, 15 ... Paper pressing plate, 17 ... Lever, 18 ... Lever shaft, 19 ... Scanner part, 20 ... Process unit, 20 ... Process unit, 21 ... Fixing part, 22 ... polygon mirror, 23 ... fθ lens, 24 ... reflecting mirror, 25 ... lens, 26 ... lower reflecting mirror, 27 ... photosensitive cartridge, 28 ... developing cartridge, 29 ... developing side housing, 30 ... toner accommodating chamber, 30c ... Left side wall 31 ... Supply roller 32 ... Developing roller 33 ... Layer thickness regulating blade 34 ... Lower frame 35 ... Upper frame 36 ... Guide 36a ... Locking 38 ... left side wall, 39 ... left side wall, 40 ... lower wall, 41 ... upper wall, 42 ... upper front wall, 43 ... rear lower wall part, 44 ... front lower wall part, 45 ... gear mechanism part, 50 ... Upper wall extension, 60 ... biasing mechanism, 61 ... rotating member, 61a ... rotating support shaft, 61b ... contact portion, 62 ... coil spring, 64 ... developing roller shaft, 65 ... rubber roller, 66 ... developing coupling, 67 ... acted part, 70 ... agitator, 71a ... stirring shaft, 73 ... coupling member, 77 ... gear cover, 84 ... positioning part, 91 ... drum side casing, 92 ... photosensitive drum, 93 ... scorotron charger, 94 DESCRIPTION OF SYMBOLS Transfer roller, 95 Cleaning brush, 122 Charging support, 123 Brush support, 124 Drum body, 125 Drum shaft, 133 Transfer roller shaft, 134 Rubber roller, 167 Left frame, 182 Fixing Frame, 183 ... heating roller, 184 ... pressure roller, 185 ... paper discharge path, 186 ... paper discharge roller, 291 ... arm, 292 ... arm part, 293 ... cam part, 294 ... thick material part, 295 ... thin material part , P ... paper.

Claims (15)

An image forming apparatus comprising: a photosensitive member cartridge having a photosensitive member on which an electrostatic latent image is formed; and a developing cartridge having a developing roller for supplying a developer to the photosensitive member and detachable from the photosensitive member cartridge. A process unit removable from the main body,
A rotary drive shaft;
Guiding means for guiding the rotation drive shaft to the developing cartridge side so as to be joinable,
The photosensitive cartridge has an urging mechanism for pressing the developing roller against the photosensitive member,
The developing cartridge is connected to an actuated portion to which an urging force is applied by the urging mechanism and a rotation driving shaft guided by the guide means, and transmits the rotation driving force by the rotation driving shaft to the developing roller. A coupling, and
When the developing cartridge is not in the normal mounting position where the developing cartridge is normally mounted, the urging mechanism is positioned in the vicinity of the developing coupling, so that the rotation drive shaft is joined to the developing coupling. To be prevented,
When the developing cartridge is in the normal mounting position, the urging mechanism is pressed and displaced by the actuated portion so that the rotation drive shaft can be joined to the developing coupling. An image forming apparatus configured to be configured. The image forming apparatus according to claim 1.
The biasing mechanism is rotatably supported at one end, and a lever member that abuts against the acting portion when the developing cartridge is attached to the photosensitive cartridge, and the lever member with respect to the lever member. An urging means for applying a force for pressing the operating portion in the direction of the developing roller, thereby applying a force for pressing the developing roller to the photosensitive member via the lever member; Consists of
When the developing cartridge is not in the normal mounting position, the lever member is positioned in the vicinity of the developing coupling, thereby preventing the rotation drive shaft from joining the developing coupling,
When the developing cartridge is in the normal mounting position, the lever member is pressed by the actuated portion and rotationally displaced, so that the rotation drive shaft can be joined to the developing coupling. An image forming apparatus comprising: The image forming apparatus according to claim 1, wherein:
The image forming apparatus, wherein the biasing mechanism and the developing coupling are provided at positions close to each other in a state where the developing cartridge is mounted on the photosensitive cartridge. The image forming apparatus according to any one of claims 1 to 3,
Two straight lines perpendicular to a straight line connecting the rotation center of the developing roller and the rotation center of the development coupling, a straight line passing through the rotation center of the developing roller, and a straight line passing through the rotation center of the development coupling. An image forming apparatus, wherein the operated part is provided in a region between the two. 5. The image forming apparatus according to claim 1, wherein:
The developer cartridge includes a developer accommodating portion that accommodates the developer, and a stirring drive shaft that agitates the developer accommodated in the developer accommodating portion and transmits a rotational driving force to the developing roller. Has
The image forming apparatus, wherein the developing coupling is provided at one end of the stirring drive shaft, and a rotational driving force by the rotational driving shaft is transmitted to the stirring driving shaft through the developing coupling. . A photoreceptor cartridge having a photoreceptor on which an electrostatic latent image is formed;
A developing cartridge having a developing roller for supplying a developer to the photosensitive member and detachable from the photosensitive cartridge,
The photosensitive cartridge has an urging mechanism for pressing the developing roller against the photosensitive member,
The developing cartridge includes an actuated portion to which an urging force by the urging mechanism is applied, and a developing coupling that is joined to the rotation driving shaft and transmits the rotation driving force of the rotation driving shaft to the developing roller. ,
When the developing cartridge is not in the normal mounting position where the developing cartridge is normally mounted, the urging mechanism is positioned in the vicinity of the developing coupling, so that the rotation drive shaft is joined to the developing coupling. To be prevented,
When the developing cartridge is in the normal mounting position, the urging mechanism is pressed and displaced by the actuated portion so that the rotation drive shaft can be joined to the developing coupling. A process unit characterized in that it is configured. The process unit according to claim 6, wherein
The biasing mechanism is rotatably supported at one end, and a lever member that abuts against the acting portion when the developing cartridge is attached to the photosensitive cartridge, and the lever member with respect to the lever member. An urging means for applying a force for pressing the action portion in the direction of the developing roller, thereby applying a force for pressing the developing roller to the photosensitive member via the lever member; Consists of
When the developing cartridge is not in the normal mounting position, the lever member is positioned in the vicinity of the developing coupling, thereby preventing the rotation drive shaft from joining the developing coupling,
When the developing cartridge is in the normal mounting position, the lever member is pressed by the actuated portion to be rotationally displaced, so that the rotation drive shaft can be joined to the developing coupling. A process unit characterized by comprising: In a process unit according to claim 6 or claim 7,
The process unit, wherein the biasing mechanism and the developing coupling are provided at positions close to each other in a state where the developing cartridge is mounted on the photosensitive cartridge. In the process unit according to any one of claims 6 to 8,
Two straight lines perpendicular to a straight line connecting the rotation center of the developing roller and the rotation center of the development coupling, a straight line passing through the rotation center of the developing roller, and a straight line passing through the rotation center of the development coupling. A process unit, wherein the actuated part is provided in a region between the two. The process unit according to any one of claims 6 to 9,
The developer cartridge includes a developer accommodating portion that accommodates the developer, and a stirring drive shaft that agitates the developer accommodated in the developer accommodating portion and transmits a rotational driving force to the developing roller. Has
The developing unit is provided at one end of the stirring drive shaft, and a rotational driving force by the rotational driving shaft is transmitted to the stirring drive shaft through the developing coupling. A developing roller for supplying a developer to a photoreceptor on which an electrostatic latent image is formed;
A housing that supports the developing roller and is detachable from the photosensitive cartridge having the photosensitive member;
A development coupling that is provided in the housing and is connected to the rotational drive shaft to transmit the rotational drive force of the rotational drive shaft to the developing roller;
An actuated portion provided on the housing and on which an urging force is applied by an urging mechanism provided on the photoconductor cartridge in order to press the developing roller against the photoconductor;
When the casing is normally mounted on the photosensitive cartridge, the actuating portion presses the biasing mechanism so that the rotation drive shaft is joined to the developing coupling. A developing cartridge which is provided at a position to be displaced so as not to block. The developing cartridge according to claim 11,
The biasing mechanism is rotatably supported at one end, and a lever member that abuts against the acting portion when the developing cartridge is attached to the photosensitive cartridge, and the lever member with respect to the lever member. An urging means for applying a force for pressing the action portion in the direction of the developing roller, thereby applying a force for pressing the developing roller to the photosensitive member via the lever member; Consists of
When the developing cartridge is not in the normal mounting position where the developing cartridge is normally mounted, the developing coupling is positioned in the vicinity of the lever member, so that the rotation drive shaft to the developing coupling is provided. Is prevented by the lever member,
When the developing cartridge is in the normal mounting position, the operated portion presses the lever member to rotationally displace the developing cartridge so that the rotary drive shaft can be joined to the developing coupling. A developing cartridge characterized by being configured. The developing cartridge according to claim 11 or 12,
The developing cartridge, wherein the developing coupling is provided at a position close to the biasing mechanism in a state where the developing cartridge is mounted on the photosensitive cartridge. The developer cartridge according to any one of claims 11 to 13,
Two straight lines perpendicular to a straight line connecting the rotation center of the developing roller and the rotation center of the development coupling, a straight line passing through the rotation center of the developing roller, and a straight line passing through the rotation center of the development coupling. A developing cartridge, wherein the actuated portion is provided in a region between the two. The developer cartridge according to any one of claims 11 to 14,
The developer cartridge includes a developer accommodating portion that accommodates the developer, and an agitation drive shaft that agitates the developer accommodated in the developer accommodating portion and transmits a rotational driving force to the developing roller. Has
The developing cartridge is provided at one end of the agitation driving shaft, and a rotational driving force by the rotational driving shaft is transmitted to the agitation driving shaft through the development coupling.

Images