The present disclosure relates to an image forming apparatus.
There has been known an image forming apparatus including a housing, a process cartridge which includes a photosensitive drum and a developing roller, and a toner cartridge accommodating therein toner. The toner cartridge is attachable to and detachable from the process cartridge. The process cartridge to which the toner cartridge is attached is attachable to and detachable from the housing. (See Japanese Patent Application Publication No. 2017-146512).
In such type of image forming apparatus, the process cartridge is attached to the housing with such a posture that the toner cartridge is positioned above the process cartridge. The toner cartridge has a lower end portion formed with a toner supply opening through which toner accommodated in the toner cartridge is supplied into the process cartridge by making use of gravity of the toner.
In the image forming apparatus where the process cartridge to which the toner cartridge is attached is attached to the housing, a user may dither over the way of replacement of the toner cartridge with a new toner cartridge between two conceivable detachment methods, one method is whether the toner cartridge is accessible to a user to eject the toner cartridge only, and the other method is whether the process cartridge is accessible to a user to eject the process cartridge along with the toner cartridge.
Further, according to a structure where the toner is supplied to the process cartridge from the toner cartridge positioned thereabove through the toner supply opening using gravity, in a case where detachment of only the toner cartridge from the process cartridge is performed while the process cartridge remains in the housing, toner accumulated around the toner supply opening of the toner cartridge may be liable to be leaked outside due to separation of the toner cartridge from the process cartridge with such a posture that the toner supply opening is positioned at a lower end portion of the toner cartridge.
In view of the foregoing, it is an object of the disclosure to provide an image forming apparatus capable of permitting a user to have no hesitation in operation of detachment of the toner cartridge from the process cartridge and avoiding leakage of toner during detachment of the toner cartridge from the process cartridge.
In order to attain the above and other objects, according to one aspect, the disclosure provides an image forming apparatus including a housing and a first process cartridge. The first process cartridge is attachable to and detachable from the housing. The first process cartridge includes a first photosensitive drum, a first developing roller, and a developing frame. The developing frame supports the first developing roller and has a toner inlet opening. The toner cartridge has a toner supply opening. The toner cartridge is positioned above the developing frame such that the toner supply opening and the toner inlet opening face with each other in upward/downward direction. In the state where the first process cartridge to which the toner cartridge is attached is attached to the housing, the toner cartridge is incapable of being detached from the first process cartridge. In a state where the first process cartridge to which the toner cartridge is attached is detached from the housing, the toner cartridge is detachable from the first process cartridge.
The particular features and advantages of the embodiment(s) as well as other objects will become apparent from the following description taken in connection with the accompanying drawings, in which:
Hereinafter, an image forming apparatus 1 according to a first embodiment of the present disclosure will be described with reference to
[Overall Structure of Image Forming Apparatus]
The image forming apparatus 1 illustrated in
In the following description, right side and left side, near side, and far side of the image forming apparatus 1 illustrated in
The image forming apparatus 1 includes a housing 2, a sheet supply tray 10 for supporting the sheet S, and an image forming unit 5 configured to form an image on the sheet S.
The housing 2 has a generally rectangular parallelepiped shape, and accommodates therein the sheet supply tray 10 and the image forming unit 5. The housing 2 has a front wall 21, a rear wall 22, and an upper wall 23. The housing 2 has a rear end and a front end which are examples of one end and another end in frontward/rearward direction, respectively. The rear wall 22 and the front wall 21 are examples of one end wall and another end wall of the housing in frontward rearward direction.
The upper wall 23 is formed with an opening 2A. The housing 2 includes a top cover 231 configured to open and close the opening 2A. The top cover 231 has a rear end portion provided with a pivot shaft 231a, and is pivotally movable about an axis of the pivot shaft 231a between a closed position where the top cover 231 closes the opening 2A and an open position where the top cover 231 opens the opening 2A. A sheet discharge tray 231b sloping diagonally downward and rearward is formed in the top cover 231.
The sheet supply tray 10 is positioned at a lower internal portion of the housing 2, and is configured to be movable in frontward/rearward direction. That is, the sheet supply tray 10 can be pulled frontward from an inward position illustrated in
A sheet conveying passage P for conveying the sheet S is provided in the housing 2, and extends from the sheet supply tray 10 to the sheet discharge tray 231b through the image forming unit 5. Inside the housing 2, a sheet supply roller 11, a separation roller 12, and a separation pad 12a are provided. Each one of sheets S supported in the sheet supply tray 10 is separated from remaining sheets, and is delivered to the sheet conveying passage P by the sheet supply roller 11, the separation roller 12 and the separation pad 12a.
The image forming unit 5 is positioned above the sheet supply tray 10 and includes four process units 50 arrayed in line in frontward/rearward direction. Each of the process units 50 is attachable to and detachable from the housing 2, and corresponds to the color of black, yellow, magenta, and cyan.
Each process unit 50 includes a process cartridge 51 and a toner cartridge 52. The process cartridge 51 is attachable to and detachable from the housing 2, and the toner cartridge 52 is attachable to and detachable from the process cartridge 51.
The process cartridge 51 includes a photosensitive drum 54, a developing unit 59, a charge roller 63 (see
The developing unit 59 includes a developing roller 55, a supply roller 56, a layer thickness regulation blade 62 (see
The toner cartridge 52 includes a toner accommodating portion 57 configured to accommodate therein toner as developing agent. The toner accommodating portion 57 is positioned above the developing unit 59. Toner is supplied from the toner accommodating portion 57 to the supply roller 56 which supplies toner to the developing roller 55. The developing roller 55 supplies toner to the photosensitive drum 54.
The top cover 231 is provided with exposure heads 53 configured to expose surfaces of the photosensitive drums 54 to light. Four exposure heads 53 are provided in one-to-one correspondence with the four photosensitive drums 54. The exposure heads 53 are arrayed in line in frontward/rearward direction. Each exposure head 53 extends downward from the top cover 231, and has a lower end portion provided with a light emitting portion 53a. The light emitting portion 53a is positioned adjacent to an upper portion of the photosensitive drum 54 in the closed state of the top cover 231. The light emitting portion 53a is constituted by an LED array in which a plurality of LED elements are arrayed in line in leftward/rightward direction.
A belt 31 is positioned below and faced with the photosensitive 0drums 54. The belt 31 is looped between a drive roller 32 and a driven roller 33 positioned frontward of the drive roller 32. Transfer rollers 34 are positioned below the photosensitive drums 54. Each of the transfer rollers 34 and each of the photosensitive drum 54 nip the endless belt 31 therebetween. A combination of the belt 31, the drive roller 32, the driven roller 33, and the transfer rollers 34 constitutes a belt unit 30.
In the image forming unit 5, after the surface of the photosensitive drum 54 is uniformly charged by the charge roller 63, the surface is locally exposed to light by the exposure head 53 on a basis of a predetermined image data. Hence, an electrostatic latent image based on the image data is formed on the surface of the photosensitive drum 54.
On the other hand, toner accommodated in the toner accommodating portion 57 is charged with positive polarity at a position between the supply roller 56 and the developing roller 55, and is carried on the surface of the developing roller 55. Then, the toner carried on the developing roller 55 is supplied to the electrostatic latent image formed on the surface of the photosensitive drum 54, so that toner image is carried on the surface of the photosensitive drum 54.
When the sheet S fed toward the image forming unit 5 from the sheet supply tray 10 is conveyed onto the belt 31, the sheet S is conveyed by the belt 31, and is successively introduced to nipping portions between the belt 31 and the photosensitive drums 54. Each transfer roller 34 is applied with transfer bias. Hence, the toner image on each photosensitive drum 54 is transferred onto the sheet S when the sheet S on the belt 31 is moved past the transfer roller 34. As such, the toner image carried on the photosensitive drum 54 is transferred to the sheet S by means of the belt unit 30.
At this time, toner that has not been transferred to the sheet S may remain on the surface of the photosensitive drum 54. The cleaning blade 64 of the drum cleaning portion 60 is configured to scrape off the residual toner from the surface of the photosensitive drum 54. Hence, the waste toner remaining on the surface of the photosensitive drum 54 is collected in the drum cleaning unit 60.
Incidentally, the belt 31 according to this embodiment is configured to support the sheet S on which toner image is transferred while the sheet S is conveyed on the belt 31. However, as a modification, the belt may be an intermediate transfer belt, such that a toner image may be initially transferred onto the intermediate transfer belt, and then, the toner image on the intermediate transfer belt may be transferred onto the sheet S.
The sheet S on which the toner image is transferred is conveyed to a fixing unit 16 positioned downstream of the image forming unit 5 in a sheet conveying direction. The fixing unit 16 includes a heat roller 17 and a pressure roller 18 in pressure contact with the heat roller 17. The toner image on the sheet S is thermally fixed to the sheet S when the sheet S is moved along a portion between the heat roller 17 and the pressure roller 18.
The sheet S on which the toner image is fixed is conveyed from the fixing unit 16 in the downstream direction of the sheet conveying direction, and the sheet S is further conveyed by a discharge roller 19 and is discharged onto the sheet discharge tray 231b.
[Toner Cartridge]
As illustrated in
The toner cartridge casing 521 has an upper end portion provided with a toner cartridge handle 521a which is gripped by a user for detaching the toner cartridge 52 from the process cartridge 51. The toner cartridge handle 521a is positioned at a rear end portion of the toner cartridge casing 521 in frontward/rearward direction in a state where the process cartridge 51 is attached to the housing 2, and the toner cartridge 52 is attached to the process cartridge 51.
A connecting portion 522 is provided below the toner accommodating portion 57 of the toner cartridge casing 521. The connecting portion 522 is connectable to the process cartridge 51 in a process of attachment of the toner cartridge 52 to the process cartridge 51. In the toner cartridge 52, toner accommodated in the toner accommodating portion 57 can be supplied to the supply roller 56 of the process cartridge 51 through the connecting portion 522.
The toner accommodating portion 57 is in communication with an interior of the connecting portion 522, so that toner accommodated in the toner accommodating portion 57 can flow into the connecting portion 522. A screw feeder 523 is provided inside the connecting portion 522. The screw feeder 523 has a rotation axis extending in leftward/rightward direction, and is configured to convey toner introduced in the connecting portion 522 leftward.
The connecting portion 522 has a lower portion having an arcuate shape protruding downward in side view. The lower end portion of the connecting portion 522 has a left end portion formed with a toner supply opening 522a through which toner is configured to pass. The toner supply opening 522a is in a form of an elongated slot extending in leftward/rightward direction.
The toner cartridge 52 further includes a toner cartridge shutter 524 configured to open and close the toner supply opening 522a. The toner cartridge shutter 524 is positioned at the left end portion of the connecting portion 522. The toner cartridge shutter 524 has a generally hollow cylindrical shape having an axis. The toner cartridge shutter 524 is disposed over the connecting portion 522 with a posture such that the axis of the toner cartridge shutter 524 extends in leftward/rightward direction. The toner cartridge shutter 524 is formed with an elongated slot as a communication opening 524a extending in leftward/rightward direction. The communication opening 524a has a size in conformance with that of the toner supply opening 522a.
A pair of first protruding portions 524b protrudes downward from the toner cartridge shutter 524 at positions outward of the toner supply opening 522a of the connecting portion 522 in leftward/rightward direction. As illustrated in
A pair of second protruding portions 525 protrudes downward from the lower end portion of the connecting portion 522 at positions outward of the toner cartridge shutter 524 in leftward/rightward direction. Positions of the second protruding portions 525 and the position of the toner supply opening 522a are coincident with each other in the circumferential direction of the connecting portion 522.
A guide rib 526A having a rectangular shape protrudes leftward from the left end of the connecting portion 522 and extends in upward/downward direction. A guide rib 526B having a rectangular shape protrudes rightward from the right end of the connecting portion 522 and extends in upward/downward direction.
The toner cartridge shutter 524 is angularly rotatable relative to the connecting portion 522 of the toner cartridge casing 521 about the axis of the toner cartridge shutter 524. Hence, the toner cartridge shutter 524 is movable between a closed position where the toner cartridge shutter 524 closes the toner supply opening 522a and an open position where the toner cartridge shutter 524 opens the toner supply opening 522a.
For example, as illustrated in
The toner cartridge shutter 524 is at the closed position when the toner supply opening 522a is closed by the toner cartridge shutter 524. In this case, angular position of the first protruding portions 524b of the toner cartridge shutter 524 is coincident with the position of the second protruding portions 525 in the circumferential direction.
Further, as illustrated in
The toner cartridge shutter 524 is at the open position when the toner supply opening 522a is opened by the toner cartridge shutter 524. In this case, angular position of the first protruding portion 524b is different from the position of the second protruding portions 525 of the connecting portion 522 in the circumferential direction. The first protruding portion 524b is positioned frontward of the second protruding portion 525.
In this way, in the toner cartridge 52, opening and closing of the toner supply opening 522a by the toner cartridge shutter 524 can be performed by angularly rotating the toner cartridge shutter 524 relative to the connecting portion 522 to change the angular position of the toner cartridge shutter 524 relative to the connecting portion 522.
The toner cartridge casing 521 includes a waste toner retaining portion 527 configured to retain waste toner collected from the surface of the photosensitive drum 54 by the drum cleaning unit 60. The waste toner retaining portion 527 is positioned leftward of the toner accommodating portion 57 and above the toner cartridge shutter 524.
The waste toner retaining portion 527 has an upper wall formed with an inlet opening 527a for introducing the waste toner to an interior of the waste toner retaining portion 527. The toner cartridge 52 includes an inlet opening shutter 528 configured to open and close the inlet opening 527a. The inlet opening shutter 528 is positioned above the waste toner retaining portion 527.
The inlet opening shutter 528 is movable in frontward/rearward direction between a closing position as illustrated in
The toner cartridge 52 further includes an urging member such as a spring 529 normally urging the inlet opening shutter 528 toward the closing position. The spring 529 is positioned above the inlet opening shutter 528. The inlet opening shutter 528 is movable to the closing position by the urging force of the spring 529. The inlet opening shutter 528 is configured to move rearward to the opening position against the urging force of the spring 529.
[Process Cartridge]
(Side Frame)
As illustrated in
The photosensitive drum 54 is rotatable about a rotation axis X1 extending in leftward/rightward direction. Leftward/rightward direction in the housing 2 is an example of a direction of the rotation axis X1 of the photosensitive drum 54 (axial direction of the photosensitive drum 54). Frontward/rearward direction in the housing 2 is an example of a first direction perpendicular to the direction of the rotation axis X1, a rear end of the housing 2 is an example of one end in the first direction, and a front end of the housing 2 is an example of another end in the first direction opposite to the one end.
The photosensitive drum 54 includes a drum body 541, a drum shaft 542A protruding leftward from the drum body 541, and a drum shaft 542B protruding rightward from the drum body 541. The drum shaft 542A constitutes a first end of the photosensitive drum 54 in the direction of the rotation axis X1, and the drum shaft 542B constitutes a second end of the photosensitive drum 54 in the direction of the rotation axis X1.
The first side frame 511A extends in a vertical direction perpendicular to the direction of the rotation axis X1, and rotatably supports the drum shaft 542A. The second side frame 511B extends in the vertical direction perpendicular to the direction of the rotation axis X1, and rotatably supports the drum shaft 542B.
The first side frame 511A is formed with a support hole 512A rotatably supporting the drum shaft 542A, and the second side frame 511B is formed with a support hole 512B rotatably supporting the drum shaft 542B.
Since the drum shafts 542A and the 542B are rotatably supported by the support holes 512A, 512B, respectively, the photosensitive drum 54 is rotatable about the rotation axis X1.
As illustrated in
The first connection frame 517 extends in leftward/rightward direction and constitutes an upper end portion of the process cartridge 51. The first connection frame 517 is spanned between the first side frame 511A and the second side frame 511B.
The first connection frame 517 is positioned above the toner cartridge 52 attached to the process cartridge 51. That is, in a state where the process cartridge 51 is attached to the housing 2 and the toner cartridge 52 is attached to the process cartridge 51, the first connection frame 517 is positioned opposite to the photosensitive drum 54 with respect to the toner cartridge 52 in upward/downward direction.
The process cartridge 51 includes a process cartridge handle 518 protruding upward from a front end portion of the first connection frame 517. The process cartridge handle 518 is a hand grip configured to be gripped by a user when the process cartridge 51 is to be detached from the housing 2.
The second connection frame 514 extends in leftward/rightward direction and is spanned between the first side frame 511A and the second side frame 511B at an intermediate position of the process cartridge 51 in upward/downward direction.
The second connection frame 514 has a left end, which is one end of the second connection frame 514 in the direction of the rotation axis X1, connected to the first side frame 511A, and has a right end, which is another end of the second connection frame 514 in the direction of the rotation axis X1, connected to the second side frame 511B. The second connection frame 514 is positioned below the toner cartridge 52 attached to the process cartridge 51.
The second connection frame 514 includes a pair of support surface portions 514a and an opening/closing surface portion 514b. The opening/closing surface portion 514b is positioned at a left portion of the second connection frame 514. One of the support surface portions 514a, which is a left second connection frame 514, extends from a left end portion of the opening/closing surface portion 514b to a left end portion of the second connection frame 514, and remaining one of the support surface portions 514a, which is a right second connection frame 514, extends from a right end portion of the opening/closing surface portion 514b to a right end portion of the second connection frame 514. The opening/closing surface portion 514b is positioned between the pair of support surface portions 514a, i.e., between the left and right second connection frames 514 in leftward/rightward direction.
The support surface portions 514a are configured to attachably and detachably support the toner cartridge casing 521 of the toner cartridge 52 attached to the process cartridge 51. In a state of supporting the toner cartridge 52 by the support surface portions 514, the toner cartridge 52 is at a posture where the toner accommodating portion 57 is positioned above the connecting portion 522.
The support surface portion 514a has an arcuate shape protruding downward in side view which is in conformance with the shape of the lower portion of the connecting portion 522. The opening/closing surface portion 514b positioned between the pair of support surface portions 514a has an arcuate shape protruding downward in side view. The arcuate shape has a radius greater than that of the arcuate shape of the support surface portion 514a.
The opening/closing surface portion 514b is formed with a toner inlet opening 514c having a shape of an elongated slot extending in leftward/rightward direction. The toner inlet opening 514c has a size corresponding to that of the toner supply opening 522a of the connecting portion 522. The toner inlet opening 514c is configured to allow toner supplied through the toner supply opening 522a of the toner cartridge 52 to pass through the toner inlet opening 514c, and is in communication with the interior of the developing frame 591.
The opening/closing surface portion 514b is formed with a pair of first recessed portions 514d at positions outward of the toner inlet opening 514c in leftward/rightward direction. Each first recessed portions 514d is configured to be engaged with each first protruding portion 524b of the toner cartridge shutter 524 upon attachment of the toner cartridge 52 to the process cartridge 51.
The first recessed portion 514d has a shape and a size corresponding to those of the first protruding portion 524b. Position of the first recessed portion 514d is different from a position of the toner inlet opening 514c in a circumferential direction of the second connection frame 514. That is, the toner inlet opening 514c is positioned rearward of the first recessed portions 514d in the circumferential direction.
The process cartridge 51 includes a process cartridge shutter 515 configured to open and close the toner inlet opening 514c of the second connection frame 514. The process cartridge shutter 515 is positioned above the opening/closing surface portion 514b.
The process cartridge shutter 515 has an arcuate shape protruding downward in side view. The process cartridge shutter 515 has a left end portion and a right end portion those slidably movably supported in the circumferential direction by the support surface portions 514a. Hence, the process cartridge shutter 515 is slidably movable relative to the opening/closing surface portion 514b in the circumferential direction.
The process cartridge shutter 515 is formed with a communication opening 515a having a shape of an elongated slot extending in leftward/rightward direction. The communication opening 515a has a size corresponding to the size of the toner supply opening 522a of the connecting portion 522. The process cartridge shutter 515 is formed with a pair of second recessed portions 515b at positions outward of the communication opening 515a in leftward/rightward direction.
Each second recessed portion 515b is configured to be engaged with each second protruding portion 525 of the toner cartridge 52 upon attachment of the toner cartridge 52 to the process cartridge 51. The second recessed portion 515b has a shape and a size corresponding to those of the second protruding portion 525. Position of the second recessed portion 515b is coincident with a position of the communication opening 515a in the circumferential direction.
The process cartridge shutter 515 is formed with a pair of insertion holes 515c each being positioned between the communication opening 515a and each second recessed portion 515b in leftward/rightward direction. The insertion hole 515c has a shape of an elongated slot extending in the circumferential direction. Each first protruding portions 524b of the toner cartridge shutter 524 is insertable through each insertion hole 515c.
The insertion hole 515c is at a position in alignment with the first recessed portions 514d of the opening/closing surface portion 514b, so that the first protruding portion 524b can be engaged with the first recessed portion 514d while the first protruding portion 524b extends through the insertion hole 515c. The insertion hole 515c has a length in the circumferential direction greater than that of the first protruding portion 524b. Hence, the process cartridge shutter 515 is slidably movable in the circumferential direction while the first protruding portion 524b extending through the insertion hole 515c is engaged with the first recessed portion 514d.
The process cartridge shutter 515 is movable between a closing position where the process cartridge shutter 515 closes the toner inlet opening 514c of the second connection frame 514 and an opening position where the process cartridge shutter 515 opens the toner inlet opening 514c by the sliding movement of the process cartridge shutter 515 relative to the second connection frame 514 in the circumferential direction.
For example, as illustrated in
The process cartridge shutter 515 is at a closed state when the toner inlet opening 514c is closed by the process cartridge shutter 515. In this case, a position of the first recessed portions 514d of the second connection frame 514 is coincident with the angular position of the second recessed portions 515b of the process cartridge shutter 515 in the circumferential direction.
On the other hand, as illustrated in
The process cartridge shutter 515 is at an open state when the toner inlet opening 514c is opened by the process cartridge shutter 515. In this case, angular position of the second recessed portions 515b of the process cartridge shutter 515 is different from the position of the first recessed portions 514d of the second connection frame 514 in the circumferential direction. The second recessed portions 515b are positioned rearward of the first recessed portions 514d.
In this way, in the process cartridge 51, opening and closing of the toner inlet opening 514c by the process cartridge shutter 515 can be performed by angularly rotating the process cartridge shutter 515 relative to the second connection frame 514 to change the angular position of the process cartridge shutter 515 relative to the second connection frame 514.
(Guide Groove)
As illustrated in
The guide grooves 513A, 513B have upper open ends. The guide ribs 526A, 526B of the toner cartridge 52 are insertable in the guide grooves 513A, 513B. The toner cartridge 52 is attachable to the process cartridge 51 by inserting the guide ribs 526A, 526B in the guide grooves 513A, 513B.
The guide ribs 526A, 526B is guided in the guide grooves 513A 513B with their inclined posture such that each lower end of each guide rib is positioned frontward of each upper end of each guide rib when the guide ribs 526A, 526B move along the inclined guide grooves 513A, 513B.
The guide grooves 513A, 513B have lower end portions formed with locking grooves 5131A, 5131B, respectively. Each of the locking grooves 5131A, 5131B has a groove width greater than a groove width of each of the guide grooves 513A, 513B in generally frontward/rearward direction. Further, as illustrated in
In the attachment state of the toner cartridge 52 to the process cartridge 51, the toner cartridge 52 is pivotally movable relative to the process cartridge 51 about a pivot axis X2 between a second position illustrated in
The pivot axis X2 is an axis of the connecting portion 522, and passes through each of the guide ribs 526A, 526B, and extends in a direction parallel to the rotation axis X1 of the photosensitive drum 54. The first position prevents the toner cartridge 52 from being detached from the process cartridge 51. The second position permits the toner cartridge 52 to be detached from the process cartridge 51.
Specifically, pivotal movement of the guide ribs 526A, 526B relative to the process cartridge 51 is restricted by the guide grooves 513A, 513B until the guide ribs 526A, 526B reach the lower end portions of the guide grooves 513A, 513B. However, the guide ribs 526A, 526B become pivotally movable relative to the process cartridge 51 when the guide ribs 526A, 526B reach the lower end portions, since the locking grooves 5131A, 5131B permit the guide ribs 526A, 526B to be pivotally movable about the pivot axis X2.
Thus, the toner cartridge 52 that is at the second position is pivotally moved to the first position relative to the process cartridge 51. Incidentally, as illustrated in
Further, upper surfaces of the guide ribs 526A, 526B are in contact with the locking grooves 5131A, 5131B when the toner cartridge 52 is at the first position. Hence, upward displacement of the toner cartridge 52 relative to the process cartridge 51 is prevented, which prevents the toner cartridge 52 that is at the first position from releasing from the process cartridge 51.
In other words, the second position of the toner cartridge 52 is a position where the toner cartridge 52 can be attached to or detached from the process cartridge 51. The first position of the toner cartridge 52 is a position where the toner cartridge 52 is fixed to the process cartridge 51.
As such, since the toner cartridge 52 is pivotally movably supported by the process cartridge 51 about the pivot axis X2 between the first position where detachment of the toner cartridge 52 from the process cartridge 51 is prevented and the second position where the toner cartridge 52 is detachable from the process cartridge 51, facilitated switching operation between the first position and the second position is attainable by simply pivotally moving the toner cartridge 52 relative to the process cartridge 51.
(Developing Unit)
As illustrated in
Guide holes 5113A, 5113B are formed in the first side frame 511A and the second side frame 511B, respectively. A left end portion of the roller shaft 55a is inserted in the guide hole 5113A, and a right end portion of the roller shaft 55a is inserted in the guide hole 5113B. The guide holes 5113A, 5113B are in the form of elongated slots. The roller shaft 55a is slidably movable relative to the guide holes 5113A, 5113B in a direction of the elongated direction of the guide holes 5113A, 5113B.
The direction of the major axis of each of the guide holes 5113A, 5113B is coincident with a direction of moving the roller shaft 55a of the developing roller 55 toward and away from the photosensitive drum 54. The roller shaft 55a is slidably movable within a longitudinal length of the guide holes 5113A, 5113B.
The developing frame 591 is movable in a first direction and a second direction opposite to the first direction by the sliding movement of the roller shaft 55a relative to the guide holes 5113A, 5113B. In first direction, the developing roller 55 is brought into pressure contact with the photosensitive drum 54. In the second direction, developing roller 55 moves away from the photosensitive drum 54. An urging member such as a spring 593 is interposed between the developing frame 591 and the second connection frame 514 as illustrated in
The developing frame 591 has an upper wall formed with an opening 591b having an elongated slot shape extending in leftward/rightward direction. The opening 591b is in communication with the interior of the developing frame 591. The opening 591b is positioned below the toner inlet opening 514c of the opening/closing surface portion 514b. The opening 591b has a size corresponding to the size of the toner inlet opening 514c.
The opening 591b and the toner inlet opening 514c are overlapped with each other in upward/downward direction, and are communicated with each other. The opening 591b and the toner inlet opening 514c are configured to allow toner to pass therethrough for supplying toner to the developing unit 59. Toner accommodated in the developing frame 591 can be supplied to the inside of the developing frame 591 through the toner inlet opening 514c and the opening 591b when the process cartridge shutter 515 is open. Toner can be accommodated in the inside of the developing frame 591.
Screws 591c, 591d are positioned in the developing frame 591 for supplying toner supplied inside the developing frame 591 to the supply roller 56 positioned in the developing chamber 59a. As such, the developing unit 59 has the opening 591b for supplying toner to the developing chamber 59a.
The screw 591c has a longitudinal end portions protruding outward from the developing frame 591 in leftward/rightward direction. The first and second side frames 511A, 511B are formed with guide holes 5114A, 5114B, respectively, in which the longitudinal end portions are inserted. The guide holes 5114A, 5114B have elongated slot shapes extending in a direction parallel to the longitudinal direction of the guide holes 5113A, 5113B. The screw 591c is slidably movable relative to the guide holes 5114A, 5114B within the longitudinal length thereof.
Thus, the developing frame 591 is movably supported by the first and second side frames 511A, 511B of the process cartridge 51, since the roller shaft 55a is slidably movable relative to the guide holes 5113A, 5113B and the screw 571c is slidably movable relative to the guide holes 5114A, 5114B.
As described above, the developing frame 591 is movable relative to the first and second side frames 511A, 511B of the process cartridge 51. Therefore, the developing roller 55 supported by the developing frame 591 is also movable relative to the photosensitive drum 54, thereby stabilizing pressure contacting state of the developing roller 55 with the photosensitive drum 54.
Further, the moving direction of the developing roller 55 together with the developing frame 591 is restricted to the extending direction of the guide holes 5114A, 5114B such that the developing roller 55 is contacted with and separated from the photosensitive drum 54 in the direction. The guide holes 5114A, 5114B can prevents the one of the end portions of the developing roller 55 from being displaced in the circumferential direction of the photosensitive drum 54, thereby maintaining parallelism between the developing roller 55 and the photosensitive drum 54.
Further, as described above, the developing frame 591 is movably supported by the first side frame 511A and the second side frame 511B, the toner inlet opening 514c is formed in the second connection frame 514, and the developing frame 591 is formed with the opening 591b in communication with the interior of the developing frame 591 and facing the toner inlet opening 514c.
With this structure, proper positional relationship suitable for developing operation can be maintained between the developing roller 55 supported by the developing frame 591 of the developing frame 591 and the photosensitive drum 54 supported by the first side frame 511A and the second side frame 511B of the process cartridge 51. Further, if the toner cartridge 52 were attached to the developing frame 591 that is movable relative to the first and second side frames 511A, 511B, operation for attaching the toner cartridge 52 to the movable developing frame 591 may be troublesome. However, according to the first embodiment, the toner cartridge 52 can be attached to the immovable second connection frame 514 fixed to the first and second side frames 511A, 511B by the formation of the toner inlet opening 514c in the second connection frame 514. Hence, operation for attaching the toner cartridge 52 to the process cartridge 51 can be facilitated.
(Seal Member)
As illustrated in
The communication opening 516a is at a position overlapping with the toner inlet opening 514c and the opening 591b in upward/downward direction allowing the toner inlet opening 514c to communicate with the opening 591b.
The seal member 516 is embedded in a space between the upper surface of the developing frame 591 and the opening/closing surface portion 514b in upward/downward direction. Since the communication opening 516a is formed in the seal member 516, a gap between a peripheral edge portion of the opening portion 591b in the upper surface of the developing frame 591 and a peripheral edge portion of the toner inlet opening 514c in the opening/closing surface portion 514b is embedded by the seal member 516. That is, the seal member 516 is provided between the peripheral edge portions of the opening 591b and the toner inlet opening 514c.
The seal member 516 is made from elastic material, for example, a sponge, and hence is expandable and shrinkable because of elastic deformation. Accordingly, in spite of change in size of the gap between the developing frame 591 and the opening/closing surface portion 514b due to movement of the developing frame 591 relative to the cartridge frame 511, the elastic deformation of the seal member 516 can follow the change in size of the gap, thereby maintaining sealing performance.
Consequently, the seal member 516 can prevent toner moving through the toner inlet opening 514c from leaking through the gap between the developing frame 591 and the opening/closing surface portion 514b.
(Waste Toner Conveying Unit)
The process cartridge 51 includes a waste toner conveying unit 61 configured to convey waste toner collected from the photosensitive drum 54 by the drum cleaning unit 60 to the waste toner retaining portion 527 of the toner cartridge 52.
Further, the charge roller 63 of the process cartridge 51 is in contact with a rear upper portion of the photosensitive drum 54 (see
In the process cartridge 51, the surface of the photosensitive drum 54 is locally exposed to light by the exposure head 53 to form an electrostatic latent image on the surface, after the surface is charged by the charge roller 63. A toner image is carried on the surface of the photosensitive drum 54 by supplying toner from the developing roller 55 to the electrostatic latent image. The toner image is transferred to the sheet S by the belt unit 30. At this time, residual toner that has not been transferred to the sheet S remains on the surface of the photosensitive drum 54. Further, foreign particles such as paper dust may be adhered to the surface of the photosensitive drum 54.
As described above, the drum cleaning unit 60 includes the cleaning blade 64 (see
In the process cartridge 51, after the residual waste toner is scraped off the surface of the photosensitive drum 54 by the cleaning blade 64, the waste toner is collected by the drum cleaning unit 60. The collected waste toner will be conveyed by the waste toner conveying unit 61 to the waste toner retaining portion 527 of the toner cartridge 52.
The waste toner conveying unit 61 includes a vertical conveyance case 611, a horizontal conveyance case 612, a belt conveyer 613, a screw 614, a waste toner conveyance shutter 615, a first abutment segment 616, and a second abutment segment 617.
The vertical conveyance case 611 extends along a left end portion of the frame 511 of the process cartridge 51 from a lower end portion to an upper end portion of the left end portion. The horizontal conveyance case 612 is positioned at an upper left end portion of the frame 511, and is connected to the vertical conveyance case 611. The horizontal conveyance case 612 has a lower end portion formed with a waste toner outlet opening 612a through which waste toner is passable.
The belt conveyer 613 is positioned inside the vertical conveyance case 611, and is configured to convey the waste toner collected by the drum cleaning unit 60 positioned at a lower end portion of the vertical conveyance case 611 to an upper end portion of the vertical conveyance case 611. The screw 614 is positioned inside the horizontal conveyance case 612 with such a posture that an axis of the screw 614 extends in leftward/rightward direction. The screw 614 is configured to convey the waste toner conveyed to the upper end portion of the vertical conveyance case 611 by the belt conveyer 613 toward the waste toner outlet opening 612a.
The waste toner conveyance shutter 615 is configured to open and close the waste toner outlet opening 612a. The waste toner conveyance shutter 615 is in a form of a generally hollow cylindrical member, and is disposed over the horizontal conveyance case 612. The waste toner conveyance shutter 615 is formed with a communication opening 615a, and is angularly rotatable relative to the horizontal conveyance case 612.
The waste toner conveyance shutter 615 is movable between an open position and a closed position by pivotal movement of the waste toner conveyance shutter 615 relative to the horizontal conveyance case 612. In the open position, the waste toner outlet opening 612a and the communication opening 615a are communicated with each other opening the waste toner outlet opening 612a. In the closed position, the waste toner outlet opening 612a is out of communication with the communication opening 615a closing the waste toner outlet opening 612a.
An urging member such as a spring 618 (
In the waste toner conveying unit 61, the first abutment segment 616 is out of abutment with the toner cartridge 52 when the toner cartridge 52 attached to the process cartridge 51 is at the second position. Hence, the waste toner conveyance shutter 615 is at the closed position by the urging force of the spring 618. On the other hand, the first abutment segment 616 is in abutment with the toner cartridge 52 when the toner cartridge 52 attached to the process cartridge 51 is at the first position. Hence, the waste toner conveyance shutter 615 is moved to the open position against the urging force of the spring 618.
The second abutment segment 617 is provided also at the waste toner conveyance shutter 615, and is movable integrally with the waste toner conveyance shutter 615. The second abutment segment 617 is abuttable on the inlet opening shutter 528 of the toner cartridge 52.
(Leg Portion)
The toner cartridge 52 includes a leg 163 movable between an accommodated position indicated by two dotted chain line in
The leg 163 is configured to be moved to the accommodated position against the urging force of the urging member when the process cartridge 51 is attached to the housing 2. The leg 163 is configured to be moved to the protruding position by the urging force of the urging member when the process cartridge 51 is detached from the housing 2.
[Opening/Closing Operation of Shutter]
As illustrated in
Then, from this state, when the guide ribs 526A, 526B of the toner cartridge 52 are inserted into the guide grooves 513A, 513B of the first and second side frames 511A, 511B, the toner cartridge 52 is guided with its inclined posture and the guide ribs 526A, 526B reach the lower end portions of the guide grooves 513A, 513B. Thus, the toner cartridge 52 is attached to the process cartridge 51.
At this time, the first protruding portions 524b of the toner cartridge shutter 524 is engaged with the first recessed portions 514d of the opening/closing surface portion 514b of the connection frame 514 of the process cartridge 51, and at the same time, the second protruding portions 525 of the toner cartridge 52 is engaged with the second recessed portions 515b of the process cartridge shutter 515.
Further, as illustrated in
The toner cartridge 52 reaching the lower end portions of the guide grooves 513A, 513B (that is, the locking grooves 5131A, 5131B) is pivotally movable about the pivot axis X2 of the connecting portion 522. Hence, as illustrated in
In the process unit 50, the toner cartridge shutter 524 and the process cartridge shutter 515 can be opened and closed by pivotally moving the toner cartridge 52 attached to the process cartridge 51 between the second position and the first position.
As illustrated in
Then, in accordance with pivotal movement of the toner cartridge 52 relative to the process cartridge 51 to the second position as illustrated in
Specifically, as a result pivotal movement of the toner cartridge 52 from the second position to the first position, the toner supply opening 522a of the toner cartridge casing 521 is moved rearward. On the other hand, the toner cartridge shutter 524 is immovable in the circumferential direction because of engagement between the first protruding portions 524b of the toner cartridge shutter 524 and the first recessed portions 514d of the connection frame 514 of the process cartridge 51.
Accordingly, the toner supply opening 522a of the toner cartridge casing 521 and the communication opening 524a of the toner cartridge shutter 524 are relatively moved in the circumferential direction to bring the toner supply opening 522a into linear alignment with the communication opening 524a in upward/downward direction. Thus, the toner supply opening 522a and the communication opening 524a are communicated with each other opening the toner cartridge shutter 524. That is, the toner cartridge shutter 524 is moved to the open position to open the toner supply opening 522a.
Further, in accordance with pivotal movement of the toner cartridge 52 from the second position to the first position, the second protruding portions 525 of the toner cartridge casing 521 is moved rearward. The process cartridge shutter 515 is also moved rearward along with the second protruding portions 525 because of the engagement of the second protruding portions 525 with the second recessed portions 515b of the process cartridge shutter 515. On the other hand, the opening/closing surface portion 514b of the connection frame 514 of the process cartridge 51 is immovable.
Therefore, the communication opening 515a of the process cartridge shutter 515 and the toner inlet opening 514c of the opening/closing surface portion 514b are relatively moved in the circumferential direction to bring the communication opening 515a into linear alignment with the toner inlet opening 514c in upward/downward direction. Hence, the communication opening 515a and the insertion hole 515c are communicated with each other opening the process cartridge shutter 515. In other words, the process cartridge shutter 515 is moved to the open position opening the toner inlet opening 514c.
Reversely, in accordance with pivotal movement of the toner cartridge 52 from the first position to the second position, the toner cartridge 52 and the toner cartridge shutter 524 are relatively moved in circumferential direction closing the toner cartridge shutter 524.
That is, the toner cartridge shutter 524 is moved to the closed position to close the toner supply opening 522a. Further, the process cartridge 51 and the process cartridge shutter 515 are relatively moved in the circumferential direction to close the process cartridge shutter 515.
As illustrated in
As illustrated in
Further, the first abutment segment 616 is brought into abutment with the toner cartridge 52 to move the waste toner conveyance shutter 615 to the opening position for opening the waste toner outlet opening 612a against the urging force of the urging member. Hence, the waste toner outlet opening 612a is opened to communicate with the inlet opening 527a. Thus, the waste toner conveyed to the waste toner outlet opening 612a can be discharged into the waste toner retaining portion 527 through the waste toner outlet opening 612a and the inlet opening 527a.
Reversely, by pivotally moving the toner cartridge 52 relative to the process cartridge 51 from the first position to the second position, the second abutment segment 617 is separated from the inlet opening shutter 528 to move the inlet opening shutter 528 to the closing position for closing the inlet opening 527a by the urging force of the spring 529. Hence, the inlet opening 527a is closed. Further, the first abutment segment 616 is separated the toner cartridge 52 to move the waste toner conveyance shutter 615 to the closing position for closing the waste toner outlet opening 612a by the urging force of the urging member. Hence, the waste toner outlet opening 612a is closed.
As such, the image forming apparatus 1 is configured such that, when the toner cartridge 52 is at the first position, the toner cartridge shutter 524 is at the open position for opening the toner supply-opening 522a, the process cartridge shutter 515 is at the open position for opening the toner inlet opening 514c, and when the toner cartridge 52 is at the second position, the toner cartridge shutter 524 is at the closed position for closing the toner supply-opening 522a, the process cartridge shutter 515 is at the closed position for closing the toner inlet opening 514c.
With this structure, in a state where the toner cartridge 52 is at the second position allowing the toner cartridge 52 to be detachable from the process cartridge 51, both the toner supply opening 522a and the toner inlet opening 514c are closed by the toner cartridge shutter 524 and the process cartridge shutter 515, respectively. Hence, leakage of toner through the toner supply opening 522a and the toner inlet opening 514c can be restrained.
Further, if large amount of toner exists at a position adjacent to the toner supply opening 522a at the time of closure of the toner cartridge shutter 524, leakage of toner through the toner inlet opening 514c may occur during closing operation of the toner cartridge shutter 524.
However, such toner leakage is avoidable. That is, the process cartridge 51 to which the toner cartridge 52 is attached is detached from the housing 2. Then, the process cartridge 51 is laid on a horizontal plane with such a posture that the process cartridge handle 518 is positioned frontward and the photosensitive drum 54 is positioned rearward or vice/versa. Then, the toner cartridge 52 is detached from the process cartridge 51. Because of the horizontal posture of the process cartridge 51 laid on the horizontal plane, toner stagnated adjacent to the toner supply opening 522a can be moved to a region away from the toner supply opening 522a because of gravity. Hence, clinging of toner to the toner cartridge shutter 524 moving toward the closed position is unlikely to occur.
[Detachment of Process Cartridge and Toner Cartridge]
As illustrated in
The first process unit 50-1 includes a first process cartridge 51-1 and a first toner cartridge 52-1. The second process unit 50-2, includes a second process cartridge 51-2 and a second toner cartridge 52-2. The third process unit 50-3 includes a third process cartridge 51-3 and a third toner cartridge 52-3. The fourth process unit 50-4 includes a fourth process cartridge 51-4 and a fourth toner cartridge 52-4.
The first process cartridge 51-1 includes a first photosensitive drum 54-1, the second process cartridge 51-2 includes a second photosensitive drum 54-2, the third process cartridge 51-3 includes a third photosensitive drum 54-3, and the fourth process cartridge 51-4 includes a fourth photosensitive drum 54-4.
The developing roller 55 of the first process cartridge 51-1 is an example of a first developing roller, and the developing roller 55 of the second process cartridge 51-2 is an example of a second developing roller. The second process cartridge 51-2 is attachable to and detachable from the housing 2, and is positioned adjacent to the first process cartridge 51-1 attached to the housing 2. Multiple color printing can be performed by the second process cartridge 51-2, the third process cartridge 51-3 and the fourth process cartridge 51-4 in addition to the first process cartridge 51-1.
The second process cartridge 51-2, the third process cartridge 51-3 and the fourth process cartridge 51-4 those attached to the housing 2 are juxtaposed to the first process cartridge 51-1 in frontward/rearward direction. Further, the rotation axes X1 of the second photosensitive drum 54-2, the third photosensitive drum 54-3 and the fourth photosensitive drum 54-4 extend parallel to the rotation axis X1 of the first photosensitive drum 54-1 in the attached state of the process cartridges 51-1 through 51-4 to the housing 2.
The process cartridge handle 518 is positioned on the upper end portion of the process cartridge 51, and the toner cartridge handle 521a is positioned on the upper end portion of the toner cartridge 52. The process cartridge handle 518 is positioned frontward of the toner cartridge handle 521a That is, the process cartridge handle 518 is positioned closer to the front wall 21 of the housing 2 than the toner cartridge handle 521a is to the front wall 21.
In the image forming apparatus 1, the process cartridge 51 can be detached from the housing 2 while the top cover 2 is opened. The front end portion of the top cover 23 is a free end portion positioned at near side for a user. Further, as described above, the sheet supply tray 10 is pulled out frontward to the separated position, which is also near side for the user.
In the open state of the top cover 23, the process cartridge handle 518 is positioned closer to the user than the toner cartridge handle 521a is to the user. Hence, the process cartridge handle 518 rather than the toner cartridge handle 521a is accessible to the user. Thus, the process cartridge 51 to which the toner cartridge 52 is attached can be detached from the housing 2 by user's gripping the process cartridge handle 518. Consequently, the user can easily and properly select the process cartridge 51 rather than toner cartridge 52 for the detachment from the housing 2.
In the image forming apparatus 1, in the state where the process cartridge 51 is attached to the housing 2 and the toner cartridge 52 is attached to the process cartridge 51, the toner cartridge 52 is positioned above the developing frame 591 such that the toner supply opening 522a of the toner cartridge 52 and the toner inlet opening 514c of the process cartridge 51 face with each other in upward/downward direction.
In the state where the process cartridge 51 to which the toner cartridge 52 is attached is attached to the housing 2, the toner cartridge 52 cannot be detached from the process cartridge 51.
For example, as illustrated in
This mechanical interference can prevent the first toner cartridge 52-1 alone from being detached from the first process cartridge 51-1. In other words, detachment of the first toner cartridge 52-1 from the first process cartridge 51-1 can be prevented with such a simple structure.
Particularly, according to the first embodiment, in the state where the first process cartridge 51-1 to which the first toner cartridge 52-1 is attached is attached to the housing 2, the second process cartridge 51-2 adjacent to the first process cartridge 51-1 can prevent the first toner cartridge 52-1 alone from being detached from the first process cartridge 51-1.
On the other hand, in state where the first process cartridge 51-1 to which the first toner cartridge 52-1 is attached is detached from the housing 2, no mechanical interference of the first toner cartridge 52-1 with the second process cartridge 51-2 occur, permitting the second toner cartridge 52-1 to be pivotally moved from the first position to the second position. Hence, the first toner cartridge 52-1 can be detached from the first process cartridge 51-1. In this way, the toner cartridge 52 can be detachable from the process cartridge 51 in the detached state of the process cartridge 51 from the housing 2.
For the exchange of the toner cartridge 52 for a new toner cartridge 52 in the image forming apparatus 1 where the process cartridge 51 to which the toner cartridge 52 is attached is attached to the housing 2, the user may be distressed by the alternative, that is, whether only the toner cartridge 52 should be accessible to the user for detaching only the toner cartridge 52, or whether the process cartridge 51 should be accessible to the user for detaching both the process cartridge 51 and the toner cartridge 52.
Further, in a structure where the toner cartridge 52 is positioned above the developing frame 591, a mechanism for supplying toner from the toner cartridge 52 to the developing frame 591 can be simplified, since the gravity can be utilized for the toner supply. However, if the toner cartridge 52 is detached from the process cartridge 51 while the toner cartridge 52 is positioned above the developing frame 591, toner leakage may occur since the toner supply opening 522a faces downward.
Against these problems, in the image forming apparatus 1 according to the first embodiment, in the state where the process cartridge 51 to which the toner cartridge 52 is attached is attached to the housing 2, the toner cartridge 52 cannot be solely detached from the housing 2. In order to detach the toner cartridge 52 from the process cartridge 51, two detaching procedure is necessary, that is, the process cartridge 51 to which the toner cartridge 52 is attached is detached from the housing 2, and then, the toner cartridge 52 is detached from the process cartridge 51. Hence, improper detaching operation is unlikely to occur without user's confusion to the detaching operation.
Further, for detaching the toner cartridge 52 from the process cartridge 51, as illustrated in
From the state illustrated in
Further, as illustrated in
With this structure, in the state where the process cartridge 51 to which the toner cartridge 52 is attached is attached to the housing 2, the toner cartridge 52 can be less likely to be detached from the process cartridge 51. Further, the structure according to the first embodiment can allow the user to facilitate visual recognition that the toner cartridge 52 cannot be solely detached from the process cartridge 51 when the toner cartridge 52 is at the first position, and allows the user to recognize necessity of pivotally moving the toner cartridge 52 for detaching the toner cartridge 52 from the process cartridge 51.
Further, the image forming apparatus 1 provides the structure such that the toner cartridge 52 faces the first connection frame 517 when the toner cartridge 52 is at the first position, and the toner cartridge 52 is offset from the first connection frame 517 when the toner cartridge 52 is at the second position.
This structure can allow the user to visually recognize that detachment of the toner cartridge 52 from the process cartridge 51 is difficult when the toner cartridge 52 is at the first position, and to visually recognize the necessity of pivotally moving the toner cartridge 52 to the second position to detach the toner cartridge 52 from the process cartridge 51.
[Regulating Member]
An image forming apparatus 101 according to a second embodiment will be described with reference to
According to the second embodiment, the process cartridge 151 further includes a lock lever 70, which is an example of a regulation member. The lock lever 70 is movable between a regulating position where the lock lever 70 prevents the toner cartridge 152 from moving from the first position to the second position and a non-regulating position where the lock lever 70 permits the toner cartridge 152 to move from the first position to the second position.
As illustrated in
As illustrated in
The lock lever 70 is pivotally movable about the axis of the pivot shaft 519 between a regulating position as indicated by a solid line in
When the lock lever 70 is at the regulating position, the locking pawl 71 is engaged with the first protrusion 521b preventing the toner cartridge 152 from moving from the first position to the second position. On the other hand, when the lock lever 70 is at the non-regulating position, engagement between the locking pawl 71 and the first protrusion 521b is released, permitting the toner cartridge 152 to move from the first position to the second position.
The operation lever 72 is configured to manually switch the position of the lock lever 70 between the regulating position and the non-regulating position. The lock lever 70 is maintained at the regulating position by the urging force of the spring 74 when no force in pivotally moving direction is imparted on the operation lever 72 because of non-operation to the operation lever 72. The lock lever 70 is movable to the non-regulating position against the urging force of the spring 74 by operating the operation lever 72 of the lock lever 70 which is at the regulating position toward the non-operating position.
In this way, because of the provision of the lock lever 70, free movement of the toner cartridge 152 from the first position to the second position can be restricted, and hence, accidental release of the toner cartridge 152 from the process cartridge 151 can be prevented.
The second side frame 511B of the process cartridge 151 includes a stopper 5115 abuttable on the lock lever 70. The stopper 5115 has a first stop surface 5115a abuttable on the locking pawl 71 and a second stop surface 5115b abuttable on the pressure lever 73.
The first stop surface 5115a prevents the lock lever 70 from further pivotal movement by the abutment of the locking pawl 71 with the first stop surface 5115a when the lock lever 70 pivotally moves toward and reaches the regulating position. The second stop surface 5115b prevents the lock lever 70 from further pivotal movement by the abutment of the pressure lever 73 with the second stop surface 5115b when the lock lever 70 pivotally moves toward and reaches the non-regulating position. Hence, the regulating position and non-regulating position can be determined.
In a state where the process cartridge 151 is attached to the housing 2, the operation lever 72 protrudes rearward of the process cartridge frame 511. For example, the operation lever 72 of the first process cartridge 151-1 protrudes rearward of the cartridge frame 511 of the first process cartridge 151-1, and the operation lever 72 of the first process cartridge 151-1 is positioned between the second process cartridge 151-2 and the cartridge frame 511 of the first process cartridge 151-1.
With this structure, the operation lever 72 of the lock lever 70 is at a narrow position between the first process cartridge 151-1 and the second process cartridge 151-2, and therefore, the operation lever 72 is not easily accessible to the user. Hence, it is difficult for the user to detach only the first toner cartridge 152-1 from the first process cartridge 151-1 attached to the housing 2. Thus, this structure can avoid erroneous detachment operation and can prompt the user to perform correct detachment operation.
Further, in the state where the process cartridge 151 to which the toner cartridge 152 is attached is attached to the housing 2, the position of the operation lever 72 when the lock lever 70 is at the regulating position is lower than the position of the operation lever 72 when the lock lever 70 is at the non-regulating position. That is, in order to operate the lock lever 70 to move from the regulating position to the non-regulating position, the operation lever 72 of the lock lever 70 must be moved upward.
Since the operation lever 72 is at the deep position in the narrow space, it is difficult for the user to operate the operation lever 72 upward to the non-regulating position. Hence, it is difficult for the user to detach only the toner cartridge 152 from the process cartridge 151 attached to the housing 2. Thus, this structure can avoid erroneous detachment operation and can prompt the user to perform correct detachment operation.
Further, the process cartridge 151 according to the second embodiment does not include a handle gripped by the user for detaching the process cartridge 151 from the housing 2. On the other hand, as illustrated in
With this structure, both the toner cartridge 152 and the process cartridge 151 can be detached from the housing 2 by user's holding and moving the toner cartridge handle 521a. At this time, detachment of the process cartridge 151 from the toner cartridge 152 is prevented by the lock lever 70. Since a handle corresponding to the process cartridge handle 518 is not provided, but only the toner cartridge handle 521a exists in the process unit 150, the second embodiment leaves the user no other option but to grip the toner cartridge handle 521a. Thus, this structure can avoid erroneous detachment operation and can prompt the user to perform correct detachment operation.
Further, as illustrated in
In this case, as illustrated in
As illustrated in
At this time, since the toner cartridge handle 521a can be moved upward by switching the lock lever 70 from the regulating position to the non-regulating position, which can facilitate further upward movement of the toner cartridge 152 to the second position by user's gripping and moving the toner cartridge handle 521a. Hence, operation for detaching the toner cartridge 152 from the process cartridge 151 can be facilitated.
Further, for moving the toner cartridge 152 from the second position to the first position, as illustrated in
In the toner cartridge 52 according to the first embodiment, the toner cartridge shutter 524 is positioned at the left end portion of the connecting portion 522. On the other hand, in the toner cartridge 152 according to the second embodiment, as illustrated in
Further, as illustrated in
For attaching the toner cartridge 152 to the process cartridge 151, the guide ribs 526A, 526B of the toner cartridge 152 are inserted into the guide grooves 513A, 513B of the second side frame 511B similar to the first embodiment as illustrated in
The first protruding portions 524b and the second protruding portions 525 of the toner cartridge shutter 524 are engaged with the first recessed portions 514d and the second recessed portions 515b of the process cartridge 151, respectively.
According to the image forming apparatus 1, 101 of the first and second embodiments, the top cover 231 can be opened and closed, and the process cartridge 51, 151 is detached from the housing 2 in the open state of the top cover 231.
In an image forming apparatus 201 according to a first modification illustrated in
The housing 202 has a front opening 2B, and includes a front wall 221 configured to open and close the front opening 2B. Further, the image forming apparatus 201 includes, instead of four exposure heads 53 of the image forming apparatus 1, 101, an exposure unit 58 configured to expose four photosensitive drums 54 to light.
The drawer 80 is movable in frontward/rearward direction between an internal position illustrated in
When the drawer 80 is at the external position illustrated in
In this way, in the structure where the process cartridge 51 is attached to the housing 202 through the drawer 80, the toner cartridge 52 cannot be detached from the process cartridge 51 in the attached state of the process cartridge 51 to the housing 202, and the toner cartridge 52 can be detached from the process cartridge 51 in the detached state of the process cartridge 51 from the housing 202.
For example, in the image forming apparatus 201, for detaching the first toner cartridge 52-1 from the first process cartridge 51-1 after moving the drawer 80 to the external position, the first toner cartridge 52-1 is mechanically interfered with the first process cartridge 51-1 in the attached state of the first process cartridge 51-1 to the housing 202, preventing the first toner cartridge 52-1 from pivotally moving toward the second position. On the other hand, the first toner cartridge 52-1 can be pivotally moved to the second position to detach the first toner cartridge 52-1 from the first process cartridge 51-1 in the detached state of the first process cartridge 51-1 from the housing 202.
Accordingly, the user has no waver about procedure of detachment of the toner cartridge from the process cartridge avoiding operation mistake. Further, leakage of toner through the toner supply opening 522a can be reduced when the toner cartridge 52 is detached from the process cartridge 51.
An image forming apparatus 301 according to a second modification is illustrated in
In the image forming apparatus 301, in the attached state of the process cartridge 151 to the housing 202, the operation lever 72 of the first process cartridge 151-1 is at a position between the body of the first process cartridge 151-1 and the second process cartridge 151-2. Hence, the operation lever 72 of the first process cartridge 151-1 is not accessible to the user. Further, upward pivotal movement is required for pivotally moving the lock lever 70 from the regulating position toward the non-regulating position. However, such an upward movement cannot be carried out because of difficult accessibility to the operation lever 72.
While the description has been made in detail with reference to the specific embodiments and modifications, it would be apparent to those skilled in the art that various changes and modifications may be made therein.
Number | Date | Country | Kind |
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2019-205799 | Nov 2019 | JP | national |
This application is a Continuation Application of U.S. patent application Ser. No. 17/652,944, filed Mar. 1, 2022, which is a Continuation Application of U.S. patent application Ser. No. 17/094,149 filed Nov. 10, 2020, and claims priority under 35 U.S.C. § 119 from Japanese Patent Application No. 2019-205799 filed Nov. 13, 2019, the entireties of which are incorporated herein by reference.
Number | Date | Country | |
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Parent | 17652944 | Mar 2022 | US |
Child | 18146492 | US | |
Parent | 17094149 | Nov 2020 | US |
Child | 17652944 | US |