This application claims priority from Japanese Patent Application No. 2021-112434 filed Jul. 6, 2021. The entire content of the priority application is incorporated herein by reference.
There has conventionally been known an image forming apparatus including a main body casing, a cover, a process cartridge, and a fixing device. The main body casing has an opening. The cover is configured to open and close the opening. The process cartridge has a photosensitive drum, and a developing device. The process cartridge is positioned between the fixing device and the cover in a state where the process cartridge is attached to the main body casing. The process cartridge can be replaced with a new one through the opening in a state where the cover is opened.
For the above conventional image forming apparatus, there is required a reduction in replacement frequency of the process cartridge.
In view of the foregoing, it is an object of the present disclosure to provide: an image forming apparatus capable of reducing replacement frequency of a process cartridge; and a process cartridge capable of reducing replacement frequency thereof.
In order to attain the above and other objects, according to one aspect, the present disclosure provides an image forming apparatus including: a main body casing, a cover, a fixing device, and a process cartridge. The main body casing has an opening. The cover is movable between a closing position where the cover closes the opening and an opening position where the cover opens the opening. The fixing device is positioned away from the cover. The process cartridge is attachable to and detachable from the main body casing through the opening in a state where the cover is at the opening position. The process cartridge is positioned between the fixing device and the cover in a state where the process cartridge is attached to the main body casing. The process cartridge includes: a photosensitive drum, a developing device, a toner receiving part, and a toner conveying part. The developing device includes a developing roller and is configured to supply toner to the photosensitive drum. The toner receiving part has a first end portion and a second end portion. The first end portion has a receiving opening for receiving toner. The first end portion is positioned outside the main body casing in a state where the process cartridge is attached to the main body casing and the cover is at the closing position. The second end portion is positioned inside the main body casing in the state where the process cartridge is attached to the main body casing and the cover is at the closing position. The toner conveying part is configured to convey toner in the toner receiving part to the developing device.
With the above configuration, when the amount of toner remaining in the developing device becomes small, the toner receiving part can be replenished with toner from the outside of the image forming apparatus in a state where the process cartridge is attached to the image forming apparatus. Further, the toner supplied to the toner receiving part is conveyed by the toner conveying part to the developing device in the image forming apparatus. Hence, when the remaining amount of toner in the developing device becomes small, the developing device can be replenished with toner without replacement of the process cartridge. As a result, replacement frequency of the process cartridge can be reduced.
According to another aspect, the present disclosure provides a process cartridge for use with an image forming apparatus. The image forming apparatus includes: a main body casing, a cover, and a fixing device. The main body casing has an opening. The cover is movable between a closing position where the cover closes the opening and an opening position where the cover opens the opening. The fixing device is positioned away from the cover. The process cartridge is attachable to and detachable from the main body casing through the opening in a state where the cover is at the opening position. The process cartridge is positioned between the fixing device and the cover in a state where the process cartridge is attached to the main body casing. The process cartridge includes: a photosensitive drum, a developing device, a toner receiving part, and a toner conveying part. The developing device includes a developing roller. The developing device is configured to supply toner to the photosensitive drum. The toner receiving part has a first end portion and a second end portion. The first end portion has a receiving opening for receiving toner. The first end portion is positioned outside the main body casing in a state where the process cartridge is attached to the main body casing and the cover is at the closing position. The second end portion is positioned inside the main body casing in the state where the process cartridge is attached to the main body casing and the cover is at the closing position. The toner conveying part is configured to convey toner in the toner receiving part to the developing device.
An overview will be given of an image forming apparatus 1 with reference to
As illustrated in
<1.1 Main Body Casing 2>
The main body casing 2 houses therein the sheet storage part 4, process cartridge 5, exposure device 6, transfer device 7, and fixing device 8. The main body casing 2 has an opening 21 (see
<1.2 Cover 3>
The cover 3 is movable between a closing position (see
<1.3 Sheet Storage Part 4>
As illustrated in
<1.4 Process Cartridge 5>
The process cartridge 5 is attachable to and detachable from the image forming apparatus 1. Specifically, the process cartridge 5 is attachable to and detachable from the main body casing 2. In a state where the process cartridge 5 is attached to the main body casing 2, the process cartridge 5 is positioned between the fixing device 8 and the cover 3 in the second direction. In a state where the process cartridge 5 is attached to the main body casing 2, the process cartridge 5 is positioned between the sheet storage part 4 and the exposure device 6 in a third direction. The third direction will be described later. In a state where the cover 3 is at the opening position (see
The process cartridge 5 includes a photosensitive drum 51, a charger 52, and a developing device 53.
<1.4.1 Photosensitive Drum 51>
The photosensitive drum 51 is rotatable about an axis A1. In a state where the process cartridge 5 is attached to the main body casing 2, the axis A1 extends in a first direction. The photosensitive drum 51 extends in the first direction. The photosensitive drum 51 has a cylindrical shape.
In a state where the process cartridge 5 is attached to the main body casing 2, the photosensitive drum 51 is positioned between the fixing device 8 and the cover 3 in the second direction. The second direction crosses the first direction. Preferably, the second direction is orthogonal to the first direction. In a state where the image forming apparatus 1 is placed on a horizontal plane, the second direction is orthogonal to both the first direction and the vertical direction.
In a state where the process cartridge 5 is attached to the main body casing 2, the photosensitive drum 51 is positioned on one side of the exposure device 6 in the third direction. The third direction crosses the first and second directions. Preferably, the third direction is orthogonal to both the first and second directions. In a state where the process cartridge 5 is attached to the main body casing 2, the photosensitive drum 51 is positioned between the sheet storage part 4 and the exposure device 6 in the third direction. In a state where the image forming apparatus 1 is placed on a horizontal plane, the third direction is the vertical direction. In a state where the image forming apparatus 1 is placed on a horizontal plane and the process cartridge 5 is attached to the main body casing 2, the photosensitive drum 51 is positioned below the exposure device 6.
<1.4.2 Charger 52>
The charger 52 is configured to charge the photosensitive drum 51. In the present embodiment, the charger 52 is a charging roller. The charger 52 may be a scorotron charger.
<1.4.3 Developing Device 53>
The developing device 53 is configured to supply toner to the photosensitive drum 51. In a state where the process cartridge 5 is attached to the main body casing 2, the developing device 53 is positioned between the photosensitive drum 51 and the cover 3 in the second direction. In a state where the process cartridge 5 is attached to the main body casing 2, the developing device 53 is positioned between the exposure device 6 and the sheet storage part 4 in the third direction. The developing device 53 includes a developing roller 531 and a developer casing 532.
The developing roller 531 is configured to supply the photosensitive drum 51 with toner stored in the developer casing 532. The developing roller 531 is in contact with the photosensitive drum 51. The developing roller 531 may be configured to come into contact with and separate from the photosensitive drum 51. In a state where the process cartridge 5 is attached to the main body casing 2, the developing roller 531 extends in the first direction. The developing roller 531 is rotatable about a developing axis A2. In a state where the process cartridge 5 is attached to the main body casing 2, the developing axis A2 extends in the first direction.
The developer casing 532 supports the developing roller 531. The developer casing 532 can store therein toner from a toner receiving part 561. The toner receiving part 561 will be described later. Specifically, the developer casing 532 has a toner storage part 533. In other words, the developing device 53 has the toner storage part 533. The toner storage part 533 can store therein toner.
<1.5 Exposure Device 6>
In a state where the process cartridge 5 is attached to the main body casing 2, the exposure device 6 is configured to expose the surface of the photosensitive drum 51 charged by the charger 52. The developing device 53 supplies toner to the exposed surface of the photosensitive drum 51. In the present embodiment, the exposure device 6 is a laser scan unit. The exposure device 6 may be an LED head.
<1.6 Transfer Device 7>
The transfer device 7 is configured to transfer toner on the photosensitive drum 51 onto the sheet S. Specifically, the sheet S fed from the sheet storage part 4 passes between the transfer device 7 and the photosensitive drum 51. At this time, the transfer device 7 transfers toner on the photosensitive drum 51 onto the sheet S. In the present embodiment, the transfer device 7 includes the transfer roller 71.
In a state where the process cartridge 5 is attached to the main body casing 2, the transfer roller 71 is positioned on one side of the photosensitive drum 51 in the third direction. In a state where the process cartridge 5 is attached to the main body casing 2, the transfer roller 71 is positioned between the photosensitive drum 51 and the sheet storage part 4 in the third direction. In a state where the process cartridge 5 is attached to the main body casing 2, the transfer roller 71 is in contact with the photosensitive drum 51. The transfer roller 71 extends in the first direction. The transfer roller 71 is rotatable about a transfer axis A3. In a state where the process cartridge 5 is attached to the main body casing 2, the transfer axis A3 extends in the first direction.
<1.7 Fixing Device 8>
The fixing device 8 is positioned away from the cover 3 in the second direction. The fixing device 8 is configured to fix toner onto the sheet S. In the present embodiment, the fixing device 8 heats and pressurizes the sheet S having toner transferred thereonto to thereby fix the toner onto the sheet S. The sheet S that has passed through the fixing device 8 is discharged to the discharge tray 9.
<1.8 Discharge Tray 9>
The discharge tray 9 can store thereon the sheet S that has passed through the fixing device 8 and then been discharged outside the main body casing 2. That is, the discharge tray 9 is a tray for storing thereon the sheet S that has passed through the fixing device 8 and then been discharged outside the main body casing 2. The discharge tray 9 is positioned on the upper surface of the main body casing 2. In other words, the discharge tray 9 is positioned on the surface of the main body casing 2 on the other side of the exposure device 6 in the third direction. The discharge tray 9 is positioned between the reading device 10 and the photosensitive drum 51 in the third direction.
<1.9 Reading Device 10>
The reading device 10 is configured to read an image of an original. The reading device 10 is positioned above the main body casing 2. In other words, the reading device 10 is positioned on the other side of the exposure device 6 in the third direction. The reading device 10 is positioned away from the discharge tray 9 in the third direction.
<1.10 Operation Panel 11>
The operation panel 11 is used for a user to input a command to the image forming apparatus 1. The operation panel 11 may be a touch panel. The operation panel 11 may include operation buttons. The operation panel 11 is positioned on one end portion of the reading device 10 in the second direction. The operation panel 11 is positioned on one end portion of the reading device 10 in the first direction.
In the image forming apparatus 1 according to the present disclosure, in a state where the process cartridge 5 is attached to the main body casing 2, the developing device 53 can be replenished with toner. To replenish the developing device 53 with toner, as illustrated in
As illustrated in
Hereinafter, with reference to
As illustrated in
<2.1 Process Frame 54>
The process frame 54 supports the photosensitive drum 51, charger 52, developing device 53, replenishing device 56, drum cleaner 58, waste toner storage part 59, and waste toner pipe 60. The process frame 54 includes a first side plate 541A and a second side plate 541B. In other words, the process cartridge 5 includes the first side plate 541A and the second side plate 541B.
The first side plate 541A is positioned at one end portion of the process frame 54 in the first direction. The first side plate 541A extends in the second and third directions. The first side plate 541A supports one end portion of the photosensitive drum 51 in the first direction, one end portion of the charger 52 in the first direction, and one end portion of the developing device 53 in the first direction. The first side plate 541A has two through holes 5411A and 5412A and an opening 5413.
As illustrated in
The through hole 5412A is positioned away from the through hole 5411A in the fourth direction. The through hole 5412A extends in the fourth direction. The through hole 5412A is an elongated hole. A projection 534A of the developing device 53 is fitted in the through hole 5412A. The projection 534A will be described later.
The opening 5413 is positioned between the through holes 5411A and 5412A in the fourth direction. The opening 5413 extends in the fourth direction. The opening 5413 has a rectangular shape. A projection 5361 of a developing electrode 536 and a projection 5371 of a supply electrode 537 penetrate the opening 5413. The developing electrode 536 and supply electrode 537 will be described later.
As illustrated in
Like the through hole 5411A, the through hole 5411B extends in the fourth direction. The through hole 5411B is an elongated hole. A projection 533B (see
Like the through hole 5412A, the through hole 5412B is positioned away from the through hole 5411B in the fourth direction. The through hole 5412B extends in the fourth direction. The through hole 5412B is an elongated hole. A projection 534B (see
<2.2 Details of Developing Device 53>
As illustrated in
In addition to the above-described developing roller 531 and developer casing 532, the developing device 53 includes two projections 533A and 533B, two projections 534A and 534B, a supply roller 535 (see
<2.2.1 Projections 533A and 533B>
As illustrated in
The projection 533B is positioned at the other end portion of the developing device 53 in the first direction. The projection 533B is positioned between the projection 534B and the photosensitive drum 51 in the fourth direction (see
<2.2.2 Projections 534A and 534B>
As illustrated in
As illustrated in
<2.2.3 Supply Roller 535>
As illustrated in
<2.2.4 Developing Electrode 536>
As illustrated in
Specifically, the developing electrode 536 is positioned at the one end portion of the developing device 53 in the first direction. The developing electrode 536 is mounted to one outer surface of the developer casing 532 in the first direction. The developing electrode 536 has one end portion 536A and the other end portion 536B. The one end portion 536A is electrically connected to the shaft of the developing roller 531. The other end 536B is positioned away from the one end portion 536A of the developing electrode 536. The other end portion 536B has the projection 5361.
As illustrated in
<2.2.5 Supply Electrode 537>
The supply electrode 537 is electrically connected to the supply roller 535. The supply electrode 537 is positioned away from the developing electrode 536. The supply electrode 537 is insulated from the developing electrode 536. An insulating member may be interposed between the supply electrode 537 and the developing electrode 536. In a state where the process cartridge 5 is attached to the main body casing 2, the supply electrode 537 is in contact with a second main body electrode (not illustrated) in the main body casing 2. The second main body electrode is positioned away from the first main body electrode. The second main body electrode is insulated from the first main body electrode. The supply electrode 537 conducts bias voltage received from the second main body electrode to the supply roller 535 to apply the bias voltage to the supply roller 535.
Specifically, the supply electrode 537 is positioned at the one end portion of the developing device 53 in the first direction. The supply electrode 537 is mounted to one outer surface of the developer casing 532 in the first direction. The supply electrode 537 has one end portion 537A and the other end portion 537B. The one end portion 537A is electrically connected to the shaft of the supply roller 535. The other end portion 537B is positioned away from the one end portion 537A of the supply electrode 537. The other end 537B has the projection 5371.
As illustrated in
<2.2.6 Receiving Port 538>
As illustrated in
<2.3 Pressing Members 55A and 55B>
As illustrated in
<2.4 Replenishing Device 56>
As illustrated in
<2.4.1 Toner Receiving Part 561>
The toner receiving part 561 is a container for receiving toner from the tonner bottle B (see
The toner receiving part 561 is positioned away from the photosensitive drum 51 in the second direction. The toner receiving part 561 is positioned away from the developing device 53 in the second direction. The toner receiving part 561 is positioned at one end portion of the process cartridge 5 in the second direction (see
As illustrated in
The receiving opening 5611 can receive toner from the toner bottle B (see
As illustrated in
As illustrated in
<2.4.2 Toner Conveying Part 562>
As illustrated in
The first toner pipe 5621 allows passage of toner from the toner receiving part 561 to the second toner pipe 5623. The first toner pipe 5621 extends in the first direction. The first toner pipe 5621 is connected to the second toner pipe 5623. The first toner pipe 5621 is in communication with the toner receiving part 561. The first toner pipe 5621 is fixed to the process frame 54. Specifically, the first toner pipe 5621 is fixed to the waste toner storage part 59.
The auger screw 5622 is configured to convey toner contained in the toner receiving part 561 toward the second toner pipe 5623 in the first direction. The auger screw 5622 is positioned inside the first toner pipe 5621. The auger screw 5622 extends in the first direction.
As illustrated in
The belt conveyer 5624 is configured to convey toner from the first toner pipe 5621 toward the toner discharge part 5625 in the second direction. The belt conveyer 5624 is positioned inside the second toner pipe 5623.
The toner discharge part 5625 can discharge toner from the second toner pipe 5623. The toner discharge part 5625 is positioned away from the first toner pipe 5621 in the second direction. The toner discharge part 5625 is positioned at the other end portion of the second toner pipe 5623 in the second direction. The toner discharge part 5625 extends from the second toner pipe 5623 toward the developing device 53. The toner discharge part 5625 extends in the third direction. The toner discharge part 5625 has a tubular shape. The toner discharge part 5625 is in communication with the second toner pipe 5623. The toner discharge part 5625 is fitted in the receiving opening 538 of the developing device 53. The toner discharge part 5625 has a discharge opening 5626.
The discharge opening 5626 allows toner to be discharged therethrough. The discharge opening 5626 is in communication with the toner storage part 533 of the developing device 53. The toner storage part 533 can store therein toner discharged from the discharge opening 5626.
<2.5 Sealing Member 57>
As illustrated in
<2.6 Drum Cleaner 58>
As illustrated in
The cleaner casing 581 is positioned between the first side plate 541A and the second side plate 541B in the first direction. The cleaner casing 581 extends in the first direction. One end portion of the cleaner casing 581 in the first direction is connected to the first side plate 541A, and the other end portion of the cleaner casing 581 in the first direction is connected to the second side plate 541B.
As illustrated in
The cleaning member 582 is mounted to the cleaner casing 581. The cleaning member 582 extends in the first direction. The cleaning member 582 has a plate-like shape. The cleaning member 582 cleans the peripheral surface of the photosensitive drum 51. Specifically, the edge of the cleaning member 582 contacts the surface of the photosensitive drum 51. When the photosensitive drum 51 rotates, the edge of the cleaning member 582 contacts waste toner on the surface of the photosensitive drum 51 to remove the waste toner from the surface of the photosensitive drum 51. The removed waste toner passes through the opening 5811 and then is stored in the cleaner casing 581.
<2.7 Waste Toner Storage part 59>
As illustrated in
As illustrated in
<2.8 Waste Toner Pipe 60>
As illustrated in
<2.9 Screw 61>
As illustrated in
(1) According to the image forming apparatus 1, as illustrated in
The toner supplied to the toner receiving part 561 is conveyed by the toner conveying part 562 to the developing device 53 in the image forming apparatus 1.
Thus, when the remaining amount of toner in the developing device 53 becomes small, the developing device 53 can be replenished with toner without replacement of the process cartridge 5.
As a result, replacement frequency of the process cartridge 5 can be reduced.
(2) According to the image forming apparatus 1, as illustrated in
Thus, even when the image forming apparatus 1 is provided with the reading device 10, an operation for replenishing the toner receiving part 561 with toner is not hindered by the reading device 10.
As a result, even when the image forming apparatus 1 is provided with the reading device 10, an operation for replenishment of toner can be smoothly performed.
(3) According to the image forming apparatus 1, as illustrated in
Thus, the operation panel 11 can be suppressed from getting dirty with toner.
(4) According to the image forming apparatus 1, as illustrated in
Thus, the receiving opening 5611 can be suppressed from being covered with the sheet S placed on the discharge tray 9.
As a result, the toner receiving part 561 can be smoothly replenished with toner even in a state where the sheet S is placed on the discharge tray 9.
(5) According to the image forming apparatus 1, as illustrated in
The sealing member 57 is elastically deformable.
The sealing member 57 is elastically deformed between the toner discharge part 5625 and the toner storage part 533 in accordance with movement of the developing device 53 relative to the photosensitive drum 51.
Thus, even when the developing device 53 moves relative to the photosensitive drum 51, the gap between the toner discharge part 5625 and the toner storage part 533 can be sealed with the sealing member 57.
As a result, even when the developing device 53 moves relative to the photosensitive drum 51, toner can be suppressed from leaking from the gap between the toner discharge part 5625 and the toner storage part 533.
(6) According to the image forming apparatus 1, as illustrated in
The amount of waste toner to be stored in the waste toner storage part 59 in a time span from a time when a new process cartridge 5 is attached to a time when the new process cartridge 5 is detached for replacement may increase due to a reduction in the replacement frequency of the process cartridge 5.
In view of this, the waste toner storage part 59 is positioned between the developing device 53 and the cover 3 in the image forming apparatus 1, as described above. This structure enables to utilize a space between the developing device 53 and the cover 3, so that a sufficient capacity can be ensured for the waste toner storage part 59.
Thus, even when the replacement frequency of the process cartridge 5 is reduced, the waste toner can be stored in the waste toner storage part 59.
(1) The image forming apparatus 1 need not necessarily be provided with the reading device 10.
(2) The receiving opening 5611 may be positioned below the discharge tray 9.
Number | Date | Country | Kind |
---|---|---|---|
2021-112434 | Jul 2021 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
11300920 | Yamada | Apr 2022 | B2 |
11561499 | Yamada | Jan 2023 | B2 |
20170285568 | Nishiyama et al. | Oct 2017 | A1 |
Number | Date | Country |
---|---|---|
2017182011 | Oct 2017 | JP |
Number | Date | Country | |
---|---|---|---|
20230010953 A1 | Jan 2023 | US |