Cartridge and image forming apparatus

A cartridge includes a cartridge main body, a protection member, a rib of the cartridge main body, and a pair of guides of the protection member, wherein an upstream-side guide of the guides can guide the rib when the cartridge main body is inserted into a device main body, and terminates the guide after allowing the cartridge main body to be inserted up to a position where the cartridge main body becomes independent of the device main body.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a cartridge detachably attachable to a device main body, and an image forming apparatus to which the cartridge is attached/detached.

Description of the Related Art

In image forming apparatuses of Japanese Patent Laid-Open No. 2007-240661, there is one in which a protection member can be positioned to a device main body, the protection member cannot be pulled out of the device main body during mount of the cartridge, and an engaging portion of the protection member is cancelled after mount of the cartridge and the protection member can be removed. This system can prevent the protection member from falling during insertion of the cartridge.

Further, this system employs a configuration in which a guide rail (support portion) is provided in the protection member, and a rib of the process cartridge is moved on the guide rail. Therefore, the protection member serves as a guide at the time of insertion of the process cartridge, and also prevents the falling.

Meanwhile, downsizing and space saving are desired for the process cartridge and the protection member in terms of downsizing a device main body and distribution of the process cartridge. Further, if the protection member is increased in size, the material is increased. Therefore, the downsizing of the protection member is advantageous to environmental issues.

However, if a configuration in which a central portion of the guide rail in a longitudinal direction is disconnected is produced in order to decrease sliding resistance caused when the process cartridge is moved along the guide rail of the protection member, the following problem may be caused. That is, when a configuration of a protection member having a U-shape likeFIG. 2of the present application is further applied in terms of downsizing and space saving of the cartridge, the protection member has no bottom surface and thus falls, and the process cartridge may not be able to be used.

SUMMARY OF THE INVENTION

It is desirable to provide a cartridge that can be suppressed from falling off a protection member at the time of insertion of the cartridge.

It is further desirable to provide a process cartridge detachably attachable to an image forming apparatus having a configuration below. The process cartridge includes: a cartridge including an image bearing member; a protection member detachably and attachably provided by being slid to the cartridge, and adapted to cover the image bearing member; a lock portion adapted to lock the protection member to be moved to the cartridge; an upstream-side rib and a downstream-side rib respectively provided at an upstream side and a downstream side of the cartridge in an inserting direction into which the cartridge is inserted into the image forming apparatus; a first support portion provided in the protection member, and adapted to support the upstream-side rib when the protection member is locked to the cartridge main body, to support the upstream-side rib in an area where the cartridge is inserted into a predetermined position of the image forming apparatus when the cartridge is inserted into the image forming apparatus, and not to support the upstream-side rib in an area where the cartridge is further inserted from the predetermined position of the image forming apparatus; and a second support portion provided in the protection member, and adapted to support the downstream-side rib when the protection member is locked to the cartridge main body.

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, embodiments for implementing the present invention will be exemplarily described in detail with reference to the drawings. Note that dimensions, materials, shapes, relative positions, and the like of configuration components described in the embodiments are appropriately changed according to a configuration of a device to which the invention is applied and various conditions. Therefore, it is not intended to limit the scope of the invention to the embodiments unless otherwise especially stated.

FIG. 1is a sectional view illustrating a configuration of an image forming apparatus1according to an embodiment of the present invention. Here, examples of the image forming apparatus include an electrophotography copying machine, an electrophotography printer (for example, an LED printer or a laser beam printer), and an electrophotography facsimile device.

The image forming apparatus1includes a device main body1A. Image forming portions10of respective colors of Y (yellow), M (magenta), C (cyan), and K (black) are arrange inside the device main body1A. The image forming portion10includes a photosensitive drum11. A charging roller12, a laser scanner13, a development device14, a cleaning blade15, and a primary transfer roller17are included around the photosensitive drum11. An intermediate transfer belt61is arranged above the photosensitive drum11. The intermediate transfer belt61is suspended around a drive roller62and rollers63and64.

A surface of the photosensitive drum11is uniformly changed by the charging roller12, and an electrostatic image is formed by the laser scanner13and is developed by the development device14with toner, so that a toner image is formed. The primary transfer roller17transfers the toner images on the surfaces of the four photosensitive drums11to the intermediate transfer belt61. A small amount of residual toner remaining on the surfaces of the photosensitive drums11is removed by the cleaning blade15, and again stands by for the next image formation. A toner cartridge19is arranged above the intermediate transfer belt61, and supplies the toner to the development device14.

Meanwhile, sheets P are fed to the cassette20one by one, and are conveyed to a pair of registration rollers23. A tip of the sheet P is formed into a loop to follow a nip portion of the pair of registration rollers23, so that skew feeding is corrected. Following that, the pair of registration rollers23conveys the sheet P between the intermediate transfer belt61and a secondary transfer outer roller35in synchronization with the toner image on the intermediate transfer belt61. The color toner image on the intermediate transfer belt61is applied predetermine welding force and electrostatic load bias in a nip portion of the drive roller62and the secondary transfer outer roller35, which are arranged to face each other, thereby to be transferred to the sheet P.

A small amount of residual toner remaining on the surface of the intermediate transfer belt61is removed and collected by a cleaning cartridge70having a cleaning blade77, and again stands by for the next image formation. The toner image transferred on the sheet P is fixed by a fixing device40by being heated and pressurized, and the sheet P is discharged onto a discharge tray50by a pair of discharge rollers41.

FIG. 2Ais a perspective view of a cartridge main body100, as viewed from a side of a rib102.FIG. 2Bis a perspective view of the cartridge main body100, as viewed from a side of a guide103.FIG. 2Cis a sectional view of the cartridge main body100. The cartridge main body100is detachably attachable to the device main body1A. The cartridge main body100includes a housing101.

The housing101includes and integrally supports the photosensitive drum11as the image forming portion10as an “image forming unit”, the charging roller12, and the cleaning blade15. The photosensitive drum11and the charging roller12are rotatably supported with respect to the housing101. The charging roller12and the cleaning blade15are supported in a state of being pressurized against the photosensitive drum11.

The photosensitive drum11is connected to a drive source (not illustrated) of the device main body1A and is rotated. The charging roller12is rotated, following the photosensitive drum11, because the charging roller12is pressurized against the photosensitive drum11. The photosensitive drum11, the charging roller12, and the cleaning blade15become deteriorated when image formation is performed. Therefore, the cartridge main body100needs to be replaced according to a print amount.

Further, a guide104that guides a rotation phase of a lock member230(lock portion) (seeFIG. 3) provided in a protection member200is provided in the cartridge main body100. A detailed operation regarding lock will be described in a procedure of replacing the cartridge main body100.

Therefore, the cartridge main body100can be inserted into a depth direction of the device main body1A and can be taken out to a front direction. A lock cancellation member16that is operated when the cartridge main body100is extracted from the device main body1A is provided in the cartridge main body100to partially protrude from the cartridge main body100.

The rib102guided to a guide212of a base body210of the protection member200at the time of insertion, and the guide103for guiding a rib213of the base body210of the protection member200are provided in the cartridge main body100. The ribs102are a pair of ribs, and are respectively provided in the cartridge main body100at an upstream side and a downstream side in an inserting direction of the cartridge main body100. The ribs102, the guide103, and the guide104extend in a direction along an attaching/detecting direction M of the cartridge main body100. Further, the image forming portion10is guided to the device main body1A by the ribs102and the guide103.

Further, the guide104that guides the rotation phase of the lock member230of the protection member200is provided in the cartridge main body100. An operation of the lock cancellation member16related to an operation at the time of insertion/extraction of the cartridge main body100and a detailed operation related to the lock member230will be described in the procedure of replacing the cartridge main body100.

FIGS. 3A and 3BandFIG. 4Aare perspective views of the protection member200. The protection member200protects the image forming portion10. The protection member200is detachably and attachably provided to the cartridge main body100, has one end open in a cross section perpendicular to the attaching/detaching direction, and covers at least a part of a surface of the cartridge main body100except a lower surface portion of the cartridge main body100.

The protection member200includes the base body210having an approximately U-shape in the cross section perpendicular to the attaching/detaching direction, a pushing-out member220independently attached to the base body210, and the lock member230. The protection member200includes an insertion portion211inserted into the device main body1A. The protection member200includes the guide212and the rib213that support the cartridge main body100and guide the cartridge main body100when the cartridge main body100is inserted into the device main body1A, inside the base body210. The rib102of the cartridge main body100passes through the guide212.

The guide212includes guides212A and212B as “a pair of support portions”. The guide212is provided in the protection member200, and supports the pair of ribs102when the protection member200is locked to the cartridge main body100.

Further, the pushing-out member220is independently attached to the base body210. As illustrated inFIG. 4B, the pushing-out member220includes an operation portion221, a pushing-out surface222, and an engaging portion223. At the time of replacement of the cartridge main body100, an operator moves the operation portion221in the inserting direction of the cartridge main body100, thereby to move the cartridge main body100while the pushing-out surface222is in contact with the cartridge main body100. The engaging portion223will be described in detail in the procedure of replacing the cartridge main body100described below.

Further, the lock member230is independently attached to the base body210. The lock member230includes a cartridge lock portion231for locking the cartridge main body100and the base body210and a cover lock portion232for locking the protection member200and the device main body1A. As illustrated inFIG. 4C, the lock member230is rotatably held to the base body210in a direction of an arrow A1.

(Protection State of Drum Cartridge)

FIG. 5Ais a perspective view of a state in which the cartridge main body100is protected by the protection member200.FIG. 5Bis a sectional view of a state in which the cartridge main body100is protected by the protection member200, as viewed from a direction of an arrow J2ofFIG. 5A.FIG. 5Cis a sectional view of a state in which the cartridge main body100is protected by the protection member200, as viewed from a direction of an arrow J3ofFIG. 5A.FIG. 6Ais a sectional view of a vicinity of the lock member230, as viewed from a direction of an arrow E ofFIG. 5B. Here, a cartridge1000includes the cartridge main body100and the protection member200.

The protection member200covers and protects the cartridge main body100, thereby to protect the photosensitive drum11, the charging roller12, and the cleaning blade15housed in the image forming portion10. The guide212of the protection member200and the rib102of the cartridge main body100are engaged with each other. The rib213of the protection member200and the guide103of the cartridge main body100are engaged with each other.

When the cartridge main body100is protected by the protection member200, the lock member230exists in the position illustrated inFIGS. 5B and 6A, and the cartridge lock portion231of the lock member230is engaged with a recessed portion100X (lock portion) of the cartridge main body100. Therefore, the lock member230locks the cartridge main body100not to be slid in a direction of an arrow B relative to the protection member200. At the same time, the protection member200is suppressed to be opened in a direction of an arrow C by the cartridge lock portion231of the lock member230and an opening-prevention rib105of the cartridge main body100.

When the base body210has an approximately U-shape, as illustrated inFIG. 3, the shape is vulnerable to deformation in the direction of the arrow C. If the base body210is deformed in the direction of the arrow C, the lock member230attached to the base body210is also moved in the direction of the arrow C, following the deformation of the base body210.

FIG. 6Bis a sectional view of a vicinity of the lock member230of when the base body210and the cartridge main body100are separated, as viewed from the direction of the arrow E ofFIG. 5B. In the position where the lock member230illustrated inFIG. 6Bhas moved in the direction of the arrow C by a fixed amount, the cartridge lock portion231of the lock member230cannot regulate the movement of the cartridge main body100in the direction of the arrow B. As a result, the cartridge main body100can be moved in the direction of the arrow B (a direction of being dropped out from the protection member200), and falls off the protection member200.

The opening-prevention rib105and the cartridge lock portion231are engaged with each other, so that the cartridge main body100can be prevented from falling off the protection member200due to the deformation of the base body210.

(Procedure of Replacing Drum Cartridge)

Next, a procedure of replacing a drum cartridge (a cartridge main body100C of cyan) using the protection member200of the present invention will be described. The procedure of replacing the cartridge main body100will be described by reference toFIGS. 7 to 16. The device main body1A provides a sign of replacement of the cartridge main body100C of cyan. A user opens a front cover400(FIG. 7A). The front cover400is provided in front of the device main body1A, and is turned to open/close. When releasing the front cover400, the user can access the cartridge main body100of the device main body1A.

The lock of the cartridge main body100C is cancelled, and the cartridge main body100C is pulled out (FIG. 7B). As illustrated inFIG. 10, the cartridge main body100C is locked to the front of the device main body1A (a direction of an arrow F) not to be dropped out with a hooking projection411provided in the cartridge rail410.

As illustrated inFIG. 11B, when the lock cancellation member16provided in the cartridge main body100C is pressed down in a direction of an arrow D, and the hooking projection411formed in a cartridge rail410is pressed down to cancel the lock of the cartridge main body100C, the cartridge main body100C can be pulled out of the device main body1A in the direction of the arrow F. After the cartridge main body100C is pulled out, the cartridge main body100C has already been used, and thus protection after pulled out may be more roughly performed than at the time of insertion because it is not a problem even if an exposure portion is damaged. The cartridge main body100C after pulled out is collected by a service person or the like.

An insertion portion201of the protection member200is inserted into a portion to be inserted301of the device main body1A in a state where the cartridge main body100C is protected by the protection member200(FIGS. 8A and 11A).

FIG. 12Ais a side view of the protection member200. As illustrated inFIG. 12A, the insertion portion201of the protection member200and the portion to be inserted301of the device main body1A have small rattling in an engagement width X. Therefore, when an insertion amount y becomes large to some extent, the protection member200does not fall even if the hand of the user is separated from the protection member200.

When the insertion portion201of the protection member200is inserted and pushed into the portion to be inserted301of the device main body1A, the cover lock portion232of the lock member230of the protection member200comes in contact with the cancellation lock rib302of the device main body1A, and the lock member230is rotated in the direction of the arrow A1. The protection member200is further pushed, the cover lock portion232enters more inside of the device main body1A than the cancellation lock rib302(FIGS. 12A to 13A).

At the same time, the lock member230is rotated in the direction of the arrow A1and is transferred to the state ofFIG. 14A, as illustrated inFIG. 12A→FIG. 12B→FIG. 13A. Then, the lock is cancelled due to the engagement of the cartridge lock portion231with the recessed portion100X of the cartridge main body100C between the protection member200and the cartridge main body100C. The cartridge main body100C can then be slid in the direction of the arrow B.

When the pushing-out member220of the protection member200is operated in the direction of the arrow B, the cartridge main body100C is pushed out by the pushing-out surface222of the pushing-out member, and only the cartridge main body100C is inserted into the device main body1A while the protection member200remains on site (FIGS. 8A and 8B).

At this time, the rib102of the cartridge main body100C and the guide212of the base body210, the guide103of the cartridge main body100and the rib213of the base body210are respectively engaged with each other, so that the cartridge main body100C is protected by the protection member200. When the cartridge main body100C is moved in the direction of the arrow B, the cartridge main body100C passes on the rib102and the guide212. At this time, if the guide212exists in the entire inserting direction (R1+R2+R3ofFIG. 15A), sliding resistance at the time of insertion of the cartridge main body100is always applied during the insertion, and operability is deteriorated.

Further, if a guide exists near the center in the longitudinal direction (R2ofFIG. 15A), the guide and the surface of the photosensitive drum11are in contact with each other when the base body210is deformed, and the photosensitive drum11may be damaged. Therefore, limiting an area where the guide212exists (R1and R3ofFIG. 15A) is effective for operability and safety of replacement of the cartridge main body100.

A minimum area necessary for the guide212is a position where the guide212supports the rib102in a state where the cartridge main body100C is protected by the protection member200. In a protection state, movement of the cartridge main body100C in the direction of the arrow B is regulated by the lock member230. Therefore, even if the guide212is provided to be limited to the area where the guide212supports the rib102, the cartridge main body100C does not fall off the protection member200at the time of distribution of the cartridge main body100. Therefore, the guide212is formed such that a section in the middle of the attaching/detaching direction of the cartridge main body100is disconnected in the position where the protection member200can support the rib102.

However, if the area where the guide212is provided is too narrow, the cartridge main body100C may fall off the protection member200in a state where the insertion amount of the cartridge main body100C to the device main body1A is small. Meanwhile, if the cartridge main body100C is inserted into the device main body1A by a fixed amount, the cartridge main body100C can be independent of the device main body1A. Therefore, the guide212for supporting the rib102is provided up to a position where the cartridge main body100C can be independent of the device main body1A (R1ofFIG. 15A).

That is, a guide212A as a taking-out direction-side portion, as a “portion at a side in a taking-out direction of the cartridge main body100” of the guide212is not disconnected up to a distance where the cartridge main body100becomes independent of the device main body1A. In doing so, the cartridge main body100C can be prevented from falling off the device main body at the time of replacement. Note that the guide212B arranged at the downstream side in the inserting direction of the cartridge has a guiding function in the present embodiment. However, the guide212B may not necessarily have the guiding function as long as the guide212B can support the rib102at least before insertion of the cartridge.

The guide212A as an “upstream support portion” arranged at an upstream side in the inserting direction of the cartridge main body100, of the pair of guides212, can guide the rib102when the cartridge main body100is inserted into the device main body1A, and terminates the guide of the rib102after allowing the cartridge main body100to be inserted up to the position where the cartridge main body100becomes independent of the device main body1A. The guide212A terminates the guide of the rib102before the cartridge main body100is half or more inserted into the device main body1A.

In the area where the guide212does not exist (R2inFIG. 15A), the pushing-out member220abuts on the cartridge main body100at a position below the cancellation member of a protruding portion300on a front surface of the cartridge main body100C (seeFIG. 15A). The pushing-out member220includes the pushing-out surface222that comes in contact with the cartridge main body100, and a part of the cartridge main body100exists at an upper side than an upper surface of the pushing-out member220in the position where the pushing-out surface222is in contact with the cartridge main body100. Therefore, the pushing-out member220can support the cartridge main body100not to fall off the protection member200. Accordingly, falling of the cartridge main body100C during insertion can be prevented by the guide212and the pushing-out member220.

The pushing-out member220is a member movably held to the protection member200, and can push out the cartridge main body100. The pushing-out member220can be moved in association with the movement of the cartridge main body100such that a part of the cartridge main body100is positioned above the pushing-out member220in the vertical direction, until the cartridge main body100is guided to the mount position of the device main body1A. The pushing-out member220includes the engaging portion223that is to be engaged with the cartridge main body100, and the engaging portion223is released from the cartridge main body100in a state where the cartridge main body100is mounted to the device main body1A.

However, if an operator directly pushes out the cartridge main body100C in the direction of the arrow B without using the pushing-out member220, the falling of the cartridge main body100in the area where no guide212exists (R2inFIG. 15A) cannot be prevented.

At this time, as illustrated inFIG. 16B, the engaging portion223of the pushing-out member220is engaged with the lock cancellation member16of the cartridge main body100, so that the pushing-out member220is moved in the direction of the arrow B, following the movement of the cartridge main body100C, and the falling in the area where no guide212exists can be prevented. With the above configuration, even if the operator performs a wrong operation, replacement work of the cartridge main body100can be safely performed.

Further, a detailed operation of the lock member230at this time will be described. The cartridge lock portion231of the lock member230is guided by the guide104of the cartridge main body100C in the direction of the arrow A2, as illustrated inFIG. 14B.

When the lock member230is rotated in the direction of the arrow A2, as illustrated inFIG. 13B, the cover lock portion232goes around behind the cancellation lock rib302of the device main body1A.

In this state, when the protection member200is pulled out of the device main body1A, the cartridge lock portion231of the lock member230is guided by the guide103of the cartridge main body100C. Therefore, the lock member230cannot be rotated, and the cover lock portion233is caught by the cancellation lock rib302of the device main body1A, and the protection member200cannot be pulled out.

If the protection member200can be pulled out in a state where the cartridge main body100C is slightly pushed out, and the protection member200is pulled out, the cartridge main body100C is in an unstable state to the protection member200and to the device main body1A, and thus falls. This can be avoided by providing the lock mechanism of the protection member200.

Further, the lock of the device main body1A and the protection member200is performed in conjunction with normal work of pushing out of the cartridge main body100C. Therefore, it is not necessary to increase an operation to lock the device main body1A and the protection member200.

When the cartridge main body100C is pushed deep, as illustrated inFIG. 8B, an inclined portion412(seeFIGS. 15B and 15C) is provided in the cartridge rail410at the downstream side in the inserting direction of the cartridge main body100, and thus the cartridge main body100C can be raised in a height direction along the inclined portion412at the end of the insertion. With this displacement, the engaging portion223of the pushing-out member220and the cartridge main body100C are disengaged, as illustrated inFIG. 16B. Therefore, the engaging portion223is released from the cartridge main body100in the state where the cartridge main body100is mounted to the device main body1A.

Further, when the cartridge main body100C is pushed deep, the cartridge lock portion231of the lock member230is guided by the guide104, and the lock member230is rotated in the direction of the arrow A1again, as illustrated inFIG. 13A. The cover lock portion232does not overlap with the cancellation lock rib302in the pulling out direction. Therefore, the protection member200can be removable state (FIG. 13C). The lock cancellation of the device main body1A and the protection member200is also performed in conjunction with a normal operation, similarly to the lock. Therefore, it is not necessary to increase an operation.

Further, when the lock is cancelled, the cartridge main body100C is independent of the device main body1A because the device main body1A and the protection member200are engaged in a state where the engagement rattling is small. Therefore, the protection member200cannot fall after completion of the insertion of the cartridge main body100C.

The protection member200is removed (FIG. 9A). The cover lock portion232comes free from the cancellation lock rib302, as illustrated inFIG. 12B. Therefore, the protection member200can be removed from the device main body1A. The front cover400is closed (seeFIG. 9B) (completion).

In the present embodiment, an example of replacing the cyan cartridge main body100C has been described. However, replacement is similarly performed for other cartridge main bodies100.

Further, in the present embodiment, an example of the cartridge main body100has been described. However, an embodiment is not limited to the example. Anything can be employed as long as the one includes an image forming unit such as a charging cartridge having only a charging function, a cleaner cartridge having only a function of a cleaner, a transfer cartridge having a transfer function, or a fixing cartridge having a fixing function.

An example of moving the cartridge main body100, using the inclined portion412provided in the cartridge main body100of the cartridge rail410attached to the device main body1A so that the engaging portion223of the pushing-out member220and the cartridge main body100are disengaged in the process of insertion has been described. Note that the engagement may be disengaged by movement of the cartridge main body100by the guide212of the protection member200, or may be disengaged by movement of the pushing-out member.

As described above, the cartridge main body100is positioned to the device main body1A in the state where the cartridge main body100is protected by the protection member200, and then the cartridge main body100is inserted into the device main body1A. In doing so, the cartridge main body100can be inserted into the device main body1A without damaging the photosensitive drum.11as the image forming portion10, the charging roller12, and the cleaning blade15.

According to the present invention, when the cartridge main body100is inserted into the device main body1A, falling of the cartridge main body100is prevented by the guide212of the protection member200until the cartridge main body100is inserted up to the position where the cartridge main body100can be independent of the device main body1A. Falling of the cartridge main body100is prevented by the pushing-out member220while the guide212is disconnected, so that falling of the cartridge main body during insertion can be prevented.

Further, by limiting the area where the guide212is provided, the sliding resistance at the time of insertion of the cartridge main body100can be reduced, and the cartridge main body100can be replaced with light operation force. Further, the guide212is not provided in the central portion in the longitudinal direction, which is easily deformed. Therefore, the contact between the guide212and the surface of the photosensitive drum11can be prevented.

Further, by engaging the pushing-out member220and the cartridge main body100, falling of the pushing-out member220can be prevented even if the operator wrongly pushes out the cartridge main body100in a direct manner.

As a result, downsizing of the protection member200can be realized while operability and safety of replacement work of the cartridge main body100can be maintained.

According to the present invention, in the configuration in which the protection member protects the cartridge and the center of the support portion provided in the protection member is disconnected, the cartridge can be prevented from falling off the protection member at the time of insertion of the cartridge.

This application claims the benefit of Japanese Patent Application No. 2015-011873, filed Jan. 24, 2015, which is hereby incorporated by reference herein in its entirety.