Patent Application
20230418219
The present invention relates to cartridges that can be attached to and detached from an apparatus body of an image forming apparatus, and to image forming apparatuses for forming images on recording materials.
In image forming apparatuses adopting an electrophotographic system, a cartridge including an image bearing member such as a photosensitive drum and a processing unit such as a developing roller acting on the image bearing member that is detachably attached integrally to an apparatus body of the image forming apparatus is used. Further, Japanese Patent Application Laid-Open Publication No. 2015-049421 discloses an image forming apparatus including a configuration in which, in a state where a process cartridge is attached to the apparatus body, a developing roller is separated from a photosensitive drum by a developing roller separating mechanism during a non-image-forming period.
In the image forming apparatus equipped with the developing roller separating mechanism, a configuration can be adopted in which, during attachment of the cartridge including a movable unit, a unit is caused to move by having a member provided on the apparatus body act on the cartridge. In such a case, there is a demand for a configuration that allows the unit to move smoothly when attaching the cartridge.
The present invention provides a configuration that allows a unit to move smoothly during attachment of the cartridge.
According to an aspect of the invention, a cartridge is configured to be attached to and detached from an apparatus body of an image forming apparatus, and the cartridge includes a first unit including an image bearing member configured to rotate about a first axis, and a second unit including a developer bearing member configured to rotate about a second axis and to bear and supply developer to the image bearing member, wherein the second unit is swingable with respect to the first unit about a swing axis that is parallel to the first axis, between a contact position in which the developer bearing member is in contact with the image bearing member and a separated position in which the developer bearing member is separated from the image bearing member, wherein the second unit includes a pressed portion to be pressed by a pressing member of the apparatus body, and is configured to be moved from the contact position to the separated position in a case where the pressed portion is pressed, and wherein, in a state where the second unit is positioned at the contact position, when viewed in an axial direction along the first axis, (i) the swing axis and the pressed portion are arranged on opposite sides to each other with respect to a virtual straight line connecting the first axis and the second axis, (ii) the pressed portion, the swing axis, and the first axis are arranged in the named order in an interaxial direction from the second axis toward the first axis along the virtual straight line, and (iii) a distance from the pressed portion to the swing axis in the interaxial direction is longer than a distance from the swing axis to the first axis in the interaxial direction.
According to another aspect of the invention, a cartridge is configured to be attached to and detached from an apparatus body of an image forming apparatus, and the cartridge includes a first unit including an image bearing member configured to rotate about a first axis, and a second unit including a developer bearing member configured to rotate about a second axis and to bear and supply developer to the image bearing member, wherein the cartridge is configured to be attached to the apparatus body in an attaching direction that is orthogonal to the first axis, wherein the second unit is swingable with respect to the first unit about a swing axis that is parallel to the first axis, between a contact position in which the developer bearing member is in contact with the image bearing member and a separated position in which the developer bearing member is separated from the image bearing member, wherein the second unit includes a pressed portion to be pressed by a pressing member of the apparatus body, and is configured to be moved from the contact position to the separated position in a case where the pressed portion is pressed, and wherein, in a state where the second unit is positioned at the contact position, when viewed in an axial direction along the first axis, (i) the swing axis and the pressed portion are arranged on opposite sides to each other with respect to a virtual straight line that passes the first axis and that extends in the attaching direction, (ii) the pressed portion, the swing axis, and the first axis are arranged in the named order in the attaching direction, and (iii) a distance from the pressed portion to the swing axis in the attaching direction is longer than a distance from the swing axis to the first axis in the attaching direction.
According to another aspect of the invention, a cartridge is configured to be attached to and detached from an apparatus body of an image forming apparatus, and the cartridge includes a first unit including an image bearing member configured to rotate about a first axis, and a second unit including a developer bearing member configured to rotate about a second axis and to bear and supply developer to the image bearing member, wherein the second unit is swingable with respect to the first unit about a swing axis that is parallel to the first axis, between a contact position in which the developer bearing member is in contact with the image bearing member and a separated position in which the developer bearing member is separated from the image bearing member, wherein the second unit includes a pressed portion to be pressed by a pressing member of the apparatus body, and is configured to be moved from the contact position to the separated position in a case where the pressed portion is pressed, and wherein, in a state where the second unit is positioned at the contact position, when viewed in an axial direction along the first axis, (i) the swing axis and the pressed portion are arranged on opposite sides to each other with respect to a virtual straight line connecting the first axis and the second axis, (ii) the pressed portion, the swing axis, and the first axis are arranged in the named order in an interaxial direction from the second axis toward the first axis along the virtual straight line, and (iii) a distance from the pressed portion to the swing axis in the interaxial direction is longer than a distance from the swing axis to a contact portion at which the image bearing member contacts the developer bearing member in the interaxial direction.
Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
An apparatus according to the present disclosure will be described below with reference to the drawings.
In the following description, the term “image forming apparatus” refers to an apparatus for forming an image on a recording material, or recording medium, u sing toner serving as developer, and includes a single-function printer, a copying machine, and a multifunction device. Sheets that are used as the recording media can include paper such as normal paper and thick paper, plastic films such as overhead projector sheets, sheets of special shapes such as envelopes and index sheets, and cloth.
The printer body A includes a sheet feeding unit 103, a transfer roller 104, a fixing unit 105, and a laser scanner 101. The process cartridge B can be attached to and detached from the printer body A. The process cartridge is a component in which an image bearing member and a process unit acting on the image bearing member are formed as a cartridge that can be detachably attached to the apparatus body of the image forming apparatus. The toner cartridge C is a cartridge that stores toner serving as developer and that is detachably attached to the image forming apparatus body. The printer body A can be referred to as a portion of the printer 1 excluding the process cartridge B and the toner cartridge C.
The process cartridge B will b e described with reference to
Hereinafter, a vertical direction, i.e., vertically upper direction, of a state in which the process cartridge B and the toner cartridge C are attached to the printer body A and the printer body A is installed on a horizontal plane is denoted by arrow Y in
One end of the process cartridge B in the longitudinal direction from which side the process cartridge B mainly receives driving force from the printer body A is referred to as a drive side, i.e., left side of
As illustrated in
The cleaning unit 10 includes the photosensitive drum 11, i.e., photosensitive drum assembly, a cleaning blade 17 serving as a cleaning member of the photosensitive drum 11, and a charging roller 12 serving as a charging member. Further, the cleaning unit 10 includes a charging roller cleaner 14 serving as a cleaning member of the charging roller 12, a waste toner primary storage portion 10a, a first waste toner conveyance path 10b, and a second waste toner conveyance path 10c.
The photosensitive drum 11 is formed by disposing a photosensitive layer formed for example of an organic photoconductor on an outer circumference side of a base formed in a cylindrical shape, or drum shape. The charging roller 12 is arranged to contact an outer circumference surface of the photosensitive drum 11. The charging roller 12 charges the photosensitive drum 11 by applying voltage from a high-voltage circuit board disposed in the printer body A. Further, the charging roller 12 is rotated by the rotation of the photosensitive drum 11, that is, rotated by following the rotation of the photosensitive drum 11.
The cleaning blade 17 is a member having elasticity arranged to contact the outer circumference surface of the photosensitive drum 11. A tip of the cleaning blade 17 is made to contact the photosensitive drum 11 elastically, removing waste toner as described later from the photosensitive drum 11. Waste toner removed by the cleaning blade 17 is conveyed from the waste toner primary storage portion 10a described below via the first waste toner conveyance path 10b and the second waste toner conveyance path 10c to the toner cartridge C.
As illustrated in
The developing roller 16 supplies toner to an image developing area of the photosensitive drum 11, that is, area of the photosensitive drum 11 facing the developing roller 16. The developing roller 16 develops an electrostatic latent image formed on the photosensitive drum 11 in the image developing area using toner. Further, a supplying roller 13 for supplying toner to the developing roller 16 is arranged in the developing chamber 151.
A developing blade 18 contacts a peripheral surface of the developing roller 16 and regulates an amount, or layer thickness, of toner adhered to the peripheral surface of the developing roller 16. Further, the developing blade 18 performs frictional charge by rubbing the toner adhered to the peripheral surface of the developing roller 16 and applies charge to toner particles.
An agitating member 154 is arranged in the developer storage chamber 152. Toner stored in the developer storage chamber 152 is transferred to the developing chamber 151 while being agitated by rotation of the agitating member 154, and supplied to the developing roller 16. The supplying roller 13 for supplying toner within the developing chamber 151 to the developing roller 16 can be arranged in the developing chamber 151.
The amount of toner within the developer storage chamber 152 is detected by a residual quantity detection unit not shown. A control unit of the printer body A executes an operation of supplying toner from the toner cartridge C to the process cartridge B in a case where the amount of toner within the developer storage chamber 152 drops to a certain amount or less based on a detection signal of the residual quantity detection unit.
The receiving chamber 153 is configured to receive toner from the toner cartridge C through a passage disposed in the cleaning unit 10. Actually, a replenishing port 21c for receiving toner from the toner cartridge C and a transfer port 21d for transferring toner to the receiving chamber 153 of the developing unit 15 are provided on a stay 21 constituting a part of the cleaning unit 10. Further, a screw 153b for conveying toner from the replenishing port 21c to the transfer port 21d is arranged in the receiving chamber 153.
Next, the operation of the printer 1 will be described with reference to
Meanwhile, in parallel with the forming of toner images, the sheet feeding unit 103 conveys sheets S one at a time. Specifically, a feed roller 103a rotates and feeds the sheets S supported on the sheet feed tray one by one. Thereafter, at a matched timing with the reaching of the toner image to the transfer portion, the sheet S is conveyed to the transfer portion. Then, while the sheet S passes the transfer portion, the toner image is transferred from the photosensitive drum 11 to the sheet S by the transfer roller 104 having a transfer voltage applied thereto from the high-voltage circuit board. Toner remaining on the surface of the photosensitive drum 11 without being transferred to the sheet S from the photosensitive drum 11 at the transfer portion, i.e., waste toner, is removed from the surface of the photosensitive drum 11 by the cleaning blade 17.
The sheet S to which the toner image has been transferred is conveyed to the fixing unit 105. The fixing unit 105 adopts a heat fixing system, and the toner image on the sheet S is heated and pressed while the sheet S is nipped and conveyed by the nip portion of the rotary member pair. Thereby, an image fixed to the sheet S is obtained. In the case of simplex printing, the sheet S having passed through the fixing unit 105 is discharged to an exterior of the printer body A by a sheet discharge roller pair serving as a sheet discharge portion, and supported on a sheet discharge tray 106 disposed on an upper side of the printer body A. In the case of duplex printing, the sheet S having an image formed on a first surface by passing through the transfer portion and the fixing unit 105 is reversed by the sheet discharge roller pair also serving as a reverse portion, and conveyed again toward the transfer portion through a re-conveyance path. The sheet S to which an image has been formed on a second surface by passing through the transfer portion and the fixing unit 105 for the second time is discharged to the exterior of the printer body A by the sheet discharge roller pair and supported on the sheet discharge tray 106 disposed on the upper side of the printer body A.
A configuration of the process cartridge B according to the present embodiment will be described in detail with reference to
As illustrated in
A frame body of the cleaning unit 10 is composed of a main frame 20, the stay 21, and a side cover 7. The main frame 20 supports the cleaning blade 17, the charging roller 12, and the charging roller cleaner 14. The photosensitive drum 11 has one side thereof rotatably supported by a drum pin 22 mounted on the main frame 20 and an opposite side thereof rotatably supported by a photosensitive drum supporting portion 7b provided on the side cover 7.
The configuration in which the developing unit 15 is supported by the cleaning unit 10 will be described in detail below. As illustrated in
A protruded portion 5b serving as a portion to be pressed, hereinafter referred to as pressed portion, of the developing unit 15 described below is a part of the bearing member 5. That is, the cylindrical portion 5a, at which the developing unit 15 is swingably supported by the cleaning unit 10, is disposed on the same member, i.e., the bearing member 5, as the protruded portion 5b. In other words, the portion at which the second unit is swingably supported by the first unit is disposed on the same member as the pressed portion. According to this configuration, the positional accuracy of the protruded portion 5b and the cylindrical portion 5a can be improved and the developing roller 16 can be moved highly accurately by being pressed by the protruded portion 5b. Alternatively, it is possible to provide a cylindrical portion serving as a projecting portion instead of the cylindrical hole 7a on the side cover 7 and to provide a cylindrical hole serving as a recess portion for fitting the cylindrical portion on the bearing member 5.
The developing unit 15 is movable about the swing axis 8 between a contact position in which the developing roller 16 contacts the photosensitive drum 11 and a separated position in which the developing roller 16 is separated from the photosensitive drum 11. Hereafter, a state of the process cartridge B in which the developing unit 15 is at a contact position is referred to as a “developing-roller contact state” and a state of the process cartridge B in which the developing unit 15 is at a separated position is referred to as a “developing-roller separated state”.
The process cartridge B includes pressurizing springs 19a and 19b serving as urging members for urging the developing unit 15. The pressurizing springs 19a and 19b are elastic members that connect the developing unit 15 and the cleaning unit 10, and tension springs are used in the illustrated configuration. The developing unit 15 is urged toward the contact position by the pressurizing springs 19a and 19b.
Further, the printer body A includes a separation mechanism 100 described below as an actuator for moving the developing unit 15 to the contact position and to the separated position. A separation lever 100a serving as a pressing member is movable between a position where the developing unit 15 is retained at the contact position and a position where the developing unit 15 is allowed to move from the contact position to the separated position. That is, the separation mechanism 100 can move the developing unit 15 from the contact position to the separated position against the urging force of the pressurizing springs 19a and 19b.
An operation in which the developing unit 15 moves between the contact position and the separated position will be described with reference to
As illustrated in
The separation mechanism 100 of the printer body A includes the separation lever 100a serving as a pressing member, a separation cam 100b for moving the separation lever 100a, and a motor 100c for driving the separation cam 100b to rotate. The separation lever 100a is disposed pivotably about an axis 100a1 that is approximately parallel to the rotational axis of the developing roller 16. Each time the motor 100c rotates the separation cam 100b for a predetermined amount, such as 180 degrees, based on a command from a control unit of the printer body A, the position of the separation lever 100a is switched between a position for pressing the protruded portion 5b and a position retreated from the protruded portion 5b.
As illustrated in
As illustrated in
The developing-roller separated state is a state in which the process cartridge B does not execute the image forming operation, that is, a state in a non-image-forming period. Further, the separated position of the developing unit 15 is the position of the developing unit 15 during the non-image-forming period, in other words, a position in which the developing unit 15 is in a state where the developer bearing member is positioned farther from the image bearing member compared to the position where the image forming process can be performed by the developer bearing member. The control unit of the printer body A controls the motor 100c to set the process cartridge B to the developing-roller separated state during the non-image-forming period, i.e., a period in which image formation is not performed, such as a period after the completion of an image forming job and before entry of a subsequent job.
When the separation lever 100a returns to an original position (
As described, a configuration is adopted in which the separation mechanism 100 can switch the process cartridge B between the developing-roller contact state and the developing-roller separated state. Therefore, for example, by setting the process cartridge B to be in the developing-roller separated state during the non-image-forming period, deterioration of toner and the photosensitive drum 11 can be suppressed and unnecessary toner consumption during the non-image-forming period can be suppressed.
The toner cartridge C will be described with reference to
As illustrated in
The directions of arrows X, Y, and Z illustrated in
One end side of the toner cartridge C in the longitudinal direction from which side the driving force is mainly entered to the toner cartridge C from the printer body A is referred to as a drive side, i.e., left side of
As illustrated in
The toner supply portion 30 is equipped with a toner storage portion 30a for storing toner, as illustrated in
The toner storage portion 30a includes a replenishing screw 35 serving as a screw member for conveying toner toward the toner discharge port 31a, and an agitating conveyance unit 36 serving as an agitating conveyance member for conveying toner toward the replenishing screw 35 while agitating toner.
The replenishing screw 35 and the agitating conveyance unit 36 each convey and agitate toner by rotating about a rotational axis extending in the longitudinal direction. That is, the replenishing screw 35 and the agitating conveyance unit 36 are each an example of a toner conveyance unit for conveying toner. The agitating conveyance unit 36 includes a shaft portion 36a that rotates by receiving transmission of driving force, and an agitating portion 36b that protrudes radially from the shaft portion 36a and that rotates together with the shaft portion 36a to convey and agitate toner. The shaft portion 36a extends in the longitudinal direction so as to pass through the toner storage portion 30a. The agitating portion 36b is formed of a resin sheet having flexibility, for example. Toner conveyed by the agitating conveyance unit 36 and the replenishing screw 35 to the toner discharge port 31a is discharged through the toner discharge port 31a by the pump unit 37.
As illustrated in
The pump 37a has a cylindrical outer shape, and a side portion of the cylindrical shape is formed in the shape of a bellows. Therefore, the pump 37a can expand and contract in a direction along the central axis of the cylindrical shape. The cam 37b and the link arm 37c constitute a cam mechanism for converting a rotational driving force entered to the toner cartridge C to a rectilinear motion in the contracting direction of the pump 37a and the expanding direction opposite thereto to thereby drive the pump 37a.
A drive configuration of the toner supply portion 30 will be described with reference to
Since the first drive input portion 38 and the second drive input portion 39 are disposed independently on the toner cartridge C, the agitating conveyance unit 36 can be controlled to be driven independently with respect to the pump unit 37 and the replenishing screw Specifically, the agitating conveyance unit 36 is driven continuously during the image-forming period, while the pump unit 37 and the replenishing screw 35 are driven intermittently only at timings at which replenishing of toner to the process cartridge B is required. The timing at which replenishing of toner is required is determined by the control unit of the printer body A based on the detection signal of the residual quantity detection unit described above.
An agitating drive side gear 38b for transmitting rotational driving force to the agitating conveyance unit 36 is arranged adjacent to the first drive input portion 38 when viewed in the longitudinal direction. The agitating drive side gear 38b is arranged on one end side in the longitudinal direction of the agitating conveyance unit 36 and coaxially therewith, and is rotated integrally with the agitating conveyance unit 36. The agitating drive side gear 38b receives driving force from the first drive input portion 38 and rotates the agitating conveyance unit 36 in an R1 direction in
A cam drive gear 39a that rotates by receiving driving force from the second drive input portion 39 is disposed next to the second drive input portion 39 when viewed in the longitudinal direction. A cam gear 39b that rotate s b y receiving driving force from the cam drive gear 39a is disposed next to the cam drive gear 39a. The cam gear 39b is formed integrally with the cam 37b. Therefore, the cam 37b of the pump unit 37 rotates by rotating the cam gear 39b accompanying the rotation of the second drive input portion 39. Then, by the rotation of the cam 37b, the link arm 37c performs rectilinear motion in the longitudinal direction, and the pump 37a expands and contracts.
A screw drive gear 39c that transmits rotational driving force to the replenishing screw 35 is disposed adjacent to the cam gear 39b when viewed in the longitudinal direction. The screw drive gear 39c is disposed coaxially with the replenishing screw 35 on one longitudinal end side thereof, and rotates integrally with the replenishing screw 35. The screw drive gear 39c receives driving force from the cam gear 39b and rotates the replenishing screw 35. By the rotation of the replenishing screw 35, toner within the toner storage portion 30a is conveyed toward the toner discharge port 31a in the longitudinal direction.
As illustrated in
Further, a positioning boss 50a and a guided portion 50b are disposed on the drive-side cover 50. These members have a function to regulate the position of the toner cartridge C when attaching the toner cartridge C to the printer body A, as described below.
Next, a general configuration of the waste toner collecting portion 40 will be described. As illustrated in
As illustrated in
The waste toner collecting portion 40 receives drive transmission as described below. As illustrated in
A gear train 710 for transmitting drive to the first waste toner screw 44 within the waste toner storage portion 40a is disposed adjacent to the agitating non-drive side gear 38a when viewed in the longitudinal direction. That is, the first waste toner screw 44 rotates by receiving rotational driving force from the printer body A via the first drive input portion 38, the agitating drive side gear 38b, the agitating conveyance unit 36, the agitating non-drive side gear 38a, and the gear train 710.
As illustrated in
A positioning boss 60a and a guided portion 60b are disposed on the non-drive-side cover 60. As descried below, these members have a function to regulate the position of the toner cartridge C when attaching the toner cartridge C to the printer body A.
Next, a method for attaching and detaching the process cartridge B and the toner cartridge C to the printer body A will be described with reference to
As illustrated in
As illustrated in
The positioning bosses 50a and 60a and the guided portions 50b and 60b are disposed on the toner cartridge C, as illustrated in
At first, the process cartridge B is attached to the printer body A. As illustrated in
In further detail, the attaching direction D of the process cartridge B is a direction along a virtual straight line L1 that connects a lower surface of the upper boss 93, i.e., first guided portion, and a lower surface of the tip boss 97, i.e., second guided portion, as illustrated in
After attaching the process cartridge B to the printer body A, the toner cartridge C is attached to the printer body A. As illustrated in
In a state where the door 107 is closed after attaching the process cartridge B and the toner cartridge C, the printer 1 is in a state ready to execute image formation.
The detachment of the toner cartridge C and the process cartridge B is performed by an opposite procedure as that described above. That is, after opening the door 107, at first, the toner cartridge C is drawn out toward an opposite direction as the attaching direction D, and thereafter, the process cartridge B is drawn out toward the opposite direction as the attaching direction D.
In the developing-roller contact state of the process cartridge B, when viewed in the longitudinal direction, a virtual straight line L2 connecting the rotational axis A11, i.e., first axis, of the photosensitive drum 11 and a rotational axis A16, i.e., second axis, of the developing roller 16 is approximately parallel to the virtual straight line L1 mentioned above. Specifically, an angle α formed by the virtual straight line L2 connecting the rotational axes A11 and A16 of the photosensitive drum 11 and the developing roller 16 and a straight line L1′ in the attaching direction D that is parallel to the virtual straight line L1 can be set to fall within the range of 3.8°±5°.
The virtual straight line L2 is parallel to the virtual straight line L1 due to the following reason, for example. The process cartridge B is attached to the printer body A in an orientation where the cleaning unit 10 is at the leading side and the developing unit 15 positioned at the trailing side with the door 107 opened (
Further, components of the process cartridge B are arranged with a space formed therebetween, such that the space allows laser light Le (
In the example, the process cartridge B includes a plurality of contacts E1 to E3 (
The plurality of contacts E1 to E3 of the developing unit 15 are aligned in a direction approximately parallel to the attaching direction D due to the following reasons. Projections such as bosses (93, 95, and 97) guided by the guide portion 108 of the printer body A are arranged on the side face portion of the process cartridge B in the longitudinal direction, such that it is desirable to arrange the contacts E1 to E3 at areas avoiding the projections in the direction orthogonal to the attaching direction D. Thereby, it becomes possible to easily allow the contacts E1 to E3 to be in contact with the contacts E4 to E6 on the printer body A by attaching the process cartridge B.
Downsizing of the developing unit 15 in the short direction can be realized by arranging the contacts E1 to E3 using the space between the upper boss 93 and the lower boss 95 of the process cartridge B. That is, the contacts E4 to E6 of the printer body are arranged on the guide portion 108 and the contacts E1 to E3 of the developing unit 15 are arranged at a position facing the guide portion 108. In this state, the contacts E1 to E3 are aligned in the attaching direction D, which is the direction in which the guide portion 108 extends, such that the contacts E1 to E3 can be arranged within the space between the upper boss 93 and the lower boss 95.
A waste toner conveyance configuration inside the cleaning unit 10 is described with reference to
As illustrated in
As mentioned above, waste toner on the photosensitive drum 11 is collected by the cleaning blade 17 into the waste toner primary storage portion 10a. In a state where the waste toner primary storage portion 10a is filled with waste toner, waste toner reaches the first waste toner conveyance path 10b. Waste toner having reached the first waste toner conveyance path is conveyed from one side in the drum axis direction toward the other side by a helical portion provided on the first waste toner conveyance unit 70, and reaches the second waste toner conveyance path 10c. Waste toner that has reached the second waste toner conveyance path 10c is conveyed by a helical portion 71a of the second waste toner conveyance unit 71 toward a direction orthogonal to the drum axis direction and upward of the cleaning blade 17. Further, waste toner being conveyed to an end portion of the second waste toner conveyance unit 71 is discharged through a waste toner discharge port 72 (
The drive configuration of the first waste toner conveyance unit 70 and the second waste toner conveyance unit 71 will be described with reference to
As illustrated in
Drive is transmitted from the drive gear 70b via an idler gear 602 and a through shaft 75 to the bevel gear 71b. The through shaft 75 is a shaft member that passes through the cleaning unit 10 in the drum axis direction. A gear 75b that meshes with the idler gear 602 is disposed on one end of the through shaft 75, and a bevel gear 75a that meshes with the bevel gear 71b is disposed on the other end thereof. As described, the first waste toner conveyance unit 70 and the second waste toner conveyance unit 71 are driven in an interlocked manner by drive transmitted from the drive gear 70b via the idler gear 602 and the through shaft 75, by which waste toner is conveyed.
The bevel gear 71b and the bevel gear 75a can be replaced with a screw gear or a worm gear. According to the present embodiment, rotating speeds of the first waste toner conveyance unit 70 and the second waste toner conveyance unit 71 are the same, but in order to enhance conveyance efficiency, the rotating speed of the second waste toner conveyance unit 71 can be set higher than the rotating speed of the first waste toner conveyance unit 70.
An arrangement of components of the process cartridge B in the short direction regarding the movement of the developing unit 15 will be described.
The virtual straight line L2 in
According to the configurations of (b) and (c) described above, in a state where the protruded portion 5b comes into contact with the separation lever 100a during attachment of the process cartridge B, the developing unit 15 can be moved from the contact position toward the separated position with smaller force. That is, compared to a case where the distance d1 is shorter than the distance d2, the distance from a point of support (swing axis 8) to a point of application of force (protruded portion 5b) of the developing unit 15 becomes longer, such that the developing unit 15 can be moved even if the force acting on the protruded portion 5b is small.
Regarding (b) described above, for example, it may be possible to arrange the protruded portion 5b on a same side, i.e., downstream side in the attaching direction D, as the rotational axis A11 of the photosensitive drum 11 with respect to the swing axis 8. However, in that case, the positional relationship causes the amount of protrusion of the protruded portion 5b in a state where the developing unit 15 swings from the contact position toward the separated position to be great, that is, the amount in which the protruded portion 5b invades the virtual straight line L2 becomes great, such that it becomes difficult to arrange the separation lever 100a. Further, according to the present embodiment, the distance in which the protruded portion 5b moves during attachment of the process cartridge B becomes long, such that the printer body A may be increased in size to ensure a space through which the protruded portion 5b passes. According to the present embodiment, the protruded portion 5b is arranged on an opposite side from the rotational axis A11 of the photosensitive drum 11 with respect to the swing axis 8, that is, upstream in the attaching direction D, such that the space within the printer body A can be utilized more effectively.
Further, instead of (c) described above, as illustrated in
As described above, the interaxial direction D′ of the photosensitive drum 11 and the developing roller 16 is approximately parallel to the attaching direction D of the process cartridge B. Therefore, the configurations of (a), (b), and (c) described above can similarly be satisfied in a case where the attaching direction D is set as reference.
That is, as illustrated in
Further, as illustrated in
Note that, the distance from the protruded portion 5b to the swing axis 8 in the attaching direction D may be longer than, instead of the distance from the swing axis 8 to the rotational axis A11 of the photosensitive drum 11 in the attaching direction D, a distance from the swing axis 8 to the contact portion at which the photosensitive drum 11 contacts the developing roller 16. In other words, a distance from the pressed portion to the swing axis in the attaching direction D may be longer than a distance from the swing axis to a contact portion at which the image bearing member contacts the developer bearing member in the attaching direction D. With this configuration, the developing unit 15 can also be moved even if the force acting on the protruded portion 5b is small.
Movement of the developing unit 15 when attaching the process cartridge B to the printer body A will be described with reference to
According to the present embodiment, even if the separation lever 100a is positioned at either a position retaining the developing unit 15 at the separated position or a position not in contact with the protruded portion 5b, attachment and detachment of the process cartridge B is enabled. In the following description, a case is illustrated where the process cartridge B is attached in a state where the separation lever 100a is at a position retaining the developing unit 15 at the separated position.
As illustrated in
In a state where the process cartridge B is gradually inserted toward the attaching direction D from the state illustrated in
Since the separation lever 100a is retained by the separation cam 100b, rotating force in the clockwise direction in the drawing (arrow R2) with respect to the swing axis 8 acts on the developing unit 15 by having the protruded portion 5b pressed by the separation lever 100a. Thereby, as illustrated in
Now, according to the configurations of (a) to (c) described above, in a state where the protruded portion 5b comes into contact with the separation lever 100a during attachment of the process cartridge B, the developing unit 15 moves to the separated position by a relatively small force. That is, according to the configuration of the present embodiment, the developing unit 15 can be moved smoothly during attachment of the cartridge. Further, since it is possible to prevent a large load to be applied to move the developing unit 15 during attachment of the cartridge, attachment of the process cartridge B becomes easy and the usability is improved.
As illustrated in
According to this configuration, the movement of the developing unit 15 during attachment of the cartridge can be easily realized. Specifically, as illustrated in
Further, as illustrated in
According to this configuration, the force that the protruded portion 5b receives when the protruded portion 5b comes into contact with the separation lever 100a during attachment of the cartridge can easily act in the direction of swinging the developing unit 15 toward the separated position, and the developing unit 15 can be moved even more smoothly. Further, the possibility of the protruded portion 5b colliding strongly against the separation lever 100a and causing the protruded portion 5b or the separation lever 100a to be damaged is reduced. Angles β and β′ are preferably 60° or less, and more preferably 45° or less.
Further, it is preferable to provide an inclined portion 100a2 at a tip portion, i.e., upstream edge in the attaching direction D or upstream edge in the interaxial direction D′, of the separation lever 100a. As illustrated in
Arrangement of components of the process cartridge B in the longitudinal direction with respect to the movement of the developing unit 15 will be described.
As illustrated in
According to this configuration, the protruded portion 5b serving as the pressed portion is arranged near the side cover 7 supporting the developing unit 15 in a swingable manner, such that torsional deformation of the developing unit 15 in a state where the protruded portion 5b is pressed can be suppressed. Further, since the protruded portion 5b is positioned on an outer side of the outer circumference surface 11a of the photosensitive drum 11 in the longitudinal direction, the possibility of the separation lever 100a in contact with the protruded portion 5b coming into contact with the outer circumference surface 11a of the photosensitive drum 11 during attachment of the cartridge can be reduced.
As illustrated in
One of the gears of the drum gears 11b and 11c serve as a gear for inputting rotational driving force to the photosensitive drum 11 and the other gear serves as a gear for generating thrust force in the longitudinal direction and positioning the photosensitive drum 11 in the longitudinal direction. However, a configuration can be adopted in which the photosensitive drum 11 is equipped with only a gear for inputting the rotational driving force.
In the above-mentioned embodiment, a configuration has been illustrated in which the developing unit 15 is retained at the contact position by urging force of the pressurizing springs 19a and 19b in a state where the protruded portion 5b of the developing unit 15 is not in contact with the separation lever 100a. Alternatively, for example, a configuration can be adopted in which, in a state where no pressurizing springs 19a and 19b are provided and the protruded portion is not in contact with the separation lever 100a, the developing unit 15 can be retained at the contact position by the own weight of the developing unit 15. Even according to this configuration, based on the configuration illustrated in the embodiment, a smooth movement of the developing unit 15 during attachment of the cartridge is enabled.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Application No. 2022-102263, filed on Jun. 24, 2022, which is hereby incorporated by reference herein in its entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-102263 | Jun 2022 | JP | national |
