Image forming apparatus and process unit

Abstract

To provide an image forming apparatus capable of easily connecting a toner container to a process cartridge.SOLUTION: The image forming apparatus 1 includes the main body housing 2, the drum unit 51 including the photosensitive drum 53, the developing unit 55 including the developing roller 59, the supply port 566 provided in the developing unit 55, the reception port 527 connected to the toner container 90, the discharge port 525 connected to the supply port 566, and the coupling portion 526 coupling the reception port 527 and the discharge port 525, which are provided in the drum unit 51, and the elastically deformable seal member 82 provided between the supply port 566 and the discharge port 525 to allow relative movement between the supply port 566 and the discharge port 525. The drum unit 51 and the developing unit 55 constitute a process cartridge 50, and in a state where the process cartridge 50 is attached to the main body housing 2, the reception port 527, the discharge port 525, and the supply port 565 at least partially overlap each other when viewed in the vertical direction.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus and a process unit. [Background technology]

[0002] As disclosed in Patent Document 1, there has been known an image forming apparatus that includes a drum unit having a photosensitive drum and a development unit having a development roller, and that is configured so that the development unit is movable relative to the drum unit in a direction in which the development roller and the photosensitive drum move closer to or farther away from each other.

[0003] In the image forming apparatus disclosed in Patent Document 1, a process cartridge is made up of a drum unit and a developing unit. A toner pack, which is a toner container for replenishing toner, is attached to a toner receiving portion of the developing unit so that toner can be replenished from the toner pack to a toner storage chamber of the developing unit. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-81064 Summary of the Invention [Problem to be solved by the invention]

[0005] However, because the developing unit is configured to be movable relative to the drum unit, the position of the toner receiving portion becomes unstable when attaching the toner pack to the toner receiving portion of the developing unit, making it difficult to attach the toner pack to the toner receiving portion.

[0006] Furthermore, if the developing unit is configured to be movable relative to the drum unit, if an impact force is accidentally transmitted to the toner receiving section when attaching the toner pack to the toner receiving section of the developing unit, the developing roller or spacer, which is configured to be in contact with the photosensitive drum, may damage the photosensitive drum.

[0007] Therefore, the present invention provides an image forming apparatus and a process unit that allow a toner container for replenishing toner to be easily connected to a process cartridge. [Means for solving the problem]

[0008] The image forming apparatus and process unit that solve the above problems have the following features.

[0009] That is, the image forming apparatus comprises a main body housing, a drum unit having a photosensitive drum, a developing unit having a developing roller, a supply port provided in the developing unit, an inlet provided in the drum unit and connected to a toner container for toner replenishment to receive toner from the toner container, an outlet provided in the drum unit and connected to the supply port, a connecting portion provided in the drum unit and connecting the inlet and the outlet, and a sealing member provided between the supply port and the outlet and made of an elastic material that can be elastically deformed to allow relative movement between the supply port and the outlet, and the drum unit and the developing unit form a process cartridge, and when the process cartridge is attached to the main body housing, the inlet, the outlet and the supply port at least partially overlap when viewed from the top and bottom.

[0010] This allows the toner container to be easily connected to the process cartridge even if the developing unit is configured to be movable relative to the drum unit. Also, the toner in the toner container can smoothly flow into the developing unit through the receiving port, the discharge port, and the supply port, allowing the toner to be smoothly replenished from the toner container to the developing unit.

[0011] The developing roller is movable relative to the photosensitive drum in a first direction that intersects with the rotation axis of the photosensitive drum, and is provided with a pressing member that presses the developing roller toward the photosensitive drum in the first direction.

[0012] As a result, if the developing roller has an outer diameter deviation, the outer diameter deviation of the developing roller can be absorbed, allowing the developing roller to rotate smoothly.

[0013] In addition, in a second direction intersecting the rotation axis of the photosensitive drum, the photosensitive drum is arranged at one end of the drum unit, the receiving port and the discharge port are arranged at the other end of the drum unit, the developing roller is arranged at one end of the developing unit, and the supply port is arranged at the other end of the developing unit.

[0014] This allows the receiving inlet and discharge outlet of the drum unit and the supply inlet of the developing unit to be positioned at the end of the main housing body, in a configuration in which the photosensitive drum and developing roller are located in the center of the main housing, improving the workability when connecting the toner container to the receiving inlet.

[0015] Furthermore, the discharge outlet is located above the supply inlet, the receiving inlet is located above the discharge outlet, the discharge outlet is formed to be the same size as the receiving inlet or larger than the receiving inlet, the supply inlet is formed to be the same size as the discharge outlet or larger than the discharge outlet, and when viewed from above and below, the discharge outlet is located within the range of the supply inlet, and the receiving inlet is located within the range of the discharge outlet.

[0016] This means that when a toner container is connected to the receiving port and toner is replenished from the toner container, the toner does not get caught on the peripheral edges of the discharge port and the supply port, and can flow smoothly into the developing unit.

[0017] The developing unit also has a toner storage chamber that communicates with the supply port and stores toner supplied from the toner container, and the bottom surface of the toner storage chamber has an inclined surface that slopes downward as it moves away from the position where the supply port is projected vertically onto the bottom surface.

[0018] This makes it possible to prevent the toner supplied to the toner storage chamber from accumulating in one place below the supply port in the toner storage chamber.

[0019] The inclined surface also has a first inclined surface that slopes downward as it approaches the developing roller from the position where the supply port is projected vertically onto the bottom surface, and a second inclined surface that slopes downward as it moves away from the position where the supply port is projected vertically onto the bottom surface along the rotational axis of the developing roller.

[0020] This allows the toner replenished in the toner storage chamber to flow in the direction from the supply port toward the developing roller and in the direction along the rotational axis of the developing roller, allowing the toner to be stored uniformly within the toner storage chamber.

[0021] The developing unit also has a protruding wall between the supply port and the developing roller, which protrudes from the bottom surface of the toner storage chamber into the toner storage chamber and extends along the rotational axis of the developing roller.

[0022] As a result, when the toner supplied from the supply port into the toner storage chamber flows toward the developing roller, it is first blocked by the protruding wall and then spreads in the direction of the rotational axis of the developing roller, allowing the toner to flow over a wide range within the toner storage chamber.

[0023] The seal member has a first portion fixed to the peripheral edge of the supply port of the developing unit, and a second portion fixed to the peripheral edge of the discharge port of the drum unit.

[0024] This improves the workability when assembling the process cartridge by assembling the drum unit and the developing unit.

[0025] The main body housing also includes a first cover having a first opening through which the process cartridge can pass and movable between a first closed position that blocks the first opening and a first open position that opens the first opening, the first cover having a second opening that can communicate with the receiving port, and a second cover provided on the first cover and movable between a second closed position that blocks the second opening and a second open position that opens the second opening.

[0026] As a result, by moving the first cover to the first open position, the process cartridge can be attached to or detached from the main body housing through the first opening. Also, by moving the second cover to the second open position while the first cover is in the first closed position, the receiving opening can be exposed to the outside, allowing the toner container to be connected to the receiving opening.

[0027] The process unit also includes a drum unit having a photosensitive drum, a development unit having a development roller, a supply port provided in the development unit, an inlet provided in the drum unit and connected to a toner container for toner replenishment to receive toner from the toner container, an outlet provided in the drum unit and connected to the supply port, a connecting portion provided in the drum unit and connecting the inlet and the outlet, and a sealing member provided between the supply port and the outlet and made of an elastic material that can be elastically deformed to allow relative movement between the supply port and the outlet, and the development unit is attached to the drum unit, and when the development unit is attached to the drum unit, the inlet, the outlet, and the supply port at least partially overlap when viewed from the direction of connection between the outlet and the supply port.

[0028] This allows the toner container to be easily connected to the process cartridge even if the developing unit is configured to be movable relative to the drum unit. Also, the toner in the toner container can smoothly flow into the developing unit through the receiving port, the discharge port, and the supply port, allowing the toner to be smoothly replenished from the toner container to the developing unit. [Effects of the Invention]

[0029] According to the present invention, the toner container can be easily connected to the process cartridge, and toner can be smoothly replenished from the toner container to the developing unit. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 2 is a central cross-sectional view showing the image forming apparatus. [Figure 2] 1 is a perspective view showing an image forming apparatus in a state where the front cover is in a first closed position and the supply cover is in a second closed position. [Figure 3] 10 is a side cross-sectional view showing a state in which the front cover has been moved to a first open position and the process cartridge has been removed from the main body housing 2 through the opening. FIG. [Figure 4] FIG. 2 is a side cross-sectional view showing the process cartridge attached to the main body housing. [Figure 5] FIG. 2 is a plan view showing the process cartridge. [Figure 6] FIG. 2 is a perspective view showing a process cartridge. [Figure 7] FIG. 2 is a perspective view showing a developing unit. [Figure 8] 1 is a perspective view showing an image forming apparatus in a state where the front cover is in a first closed position and the supply cover is in a second open position. [Figure 9] FIG. 10 is a side cross-sectional view showing a state in which the toner container is connected to the receiving port of the drum unit. [Figure 10] FIG. 10 is a side cross-sectional view showing a modified example of the seal member. DETAILED DESCRIPTION OF THE INVENTION

[0031] Next, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0032] [Image forming equipment] An image forming apparatus 1 shown in FIG. 1 is one embodiment of the image forming apparatus according to the present invention, and is a laser printer that forms an image on a sheet S by electrophotography.

[0033] In the following description, the right side in Fig. 1 is defined as the front side of the image forming apparatus 1, the left side in Fig. 1 is defined as the rear side of the image forming apparatus 1, the front side of the paper in Fig. 1 is defined as the left side of the image forming apparatus 1, and the back side of the paper in Fig. 1 is defined as the right side of the image forming apparatus 1. In addition, the upper and lower sides in Fig. 1 are defined as the upper and lower sides of the image forming apparatus 1, respectively.

[0034] The image forming apparatus 1 includes a main body housing 2, a paper feed unit 3, an image forming unit 5, a fixing unit 6, and a paper discharge unit 7. The main body housing 2 houses the paper feed unit 3, the image forming unit 5, the fixing unit 6, and the paper discharge unit 7.

[0035] 1 to 3, an opening 2A is formed at the front end of the main body housing 2, and the main body housing 2 has a front cover 21 that can open and close the opening 2A. The opening 2A is an example of a first opening, and the front cover 21 is an example of a first cover.

[0036] The front cover 21 is located at the lower end of the front cover 21 and is configured to be rotatable about a rotation shaft 21a extending in the left-right direction. By rotating about the rotation shaft 21a, the front cover 21 can move between a first closed position (position shown in FIG. 1) where the opening 2A is closed and a first open position (position shown in FIG. 3) where the opening 2A is opened. The front cover 21 located at the first open position is located forward of the front cover 21 located at the first closed position.

[0037] The paper feed unit 3 includes a paper feed tray 10 that supports the sheet S, a sheet transport unit 30, a transport roller pair 34, and a registration roller 35a. The paper feed unit 3 is disposed in the lower part of the main body housing 2, and transports the sheet S supported on the paper feed tray 10 to the image forming unit 5. The image forming apparatus 1 has a transport path P for the sheet S that runs from the paper feed unit 3 to the paper discharge unit 7 via the image forming unit 5.

[0038] The sheet conveying unit 30 is a conveying mechanism that separates and picks up the sheets S supported in the paper feed tray 10 one by one and conveys them toward the image forming unit 5, and is equipped with a paper feed roller 31, a separation roller 32, and a separation pad 33.

[0039] The paper feed roller 31 is a roller for sending the sheet S supported on the paper feed tray 10 toward the separation roller 32. The separation roller 32 is disposed downstream of the paper feed roller 31 in the sheet conveying direction, and the separation pad 33 is disposed opposite the separation roller 32 and is urged toward the separation roller 32.

[0040] The sheets S sent out by the paper feed roller 31 toward the separation roller 32 are separated one by one between the separation roller 32 and the separation pad 33. The separated sheets S are sent out to a conveying path P.

[0041] The sheet S sent to the conveying path P is conveyed toward the image forming unit 5 by the conveying roller pair 34, the registration roller 35a, and the pinch roller 35b arranged opposite the registration roller 35a. The registration roller 35a regulates the movement of the leading edge of the conveyed sheet S, temporarily stops the sheet S, and then conveys the sheet S toward the image forming unit 5 at a predetermined timing.

[0042] The image forming unit 5 is disposed downstream of the paper feed unit 3 in the sheet transport direction, and forms an image on the sheet S transported from the paper feed unit 3. The image forming unit 5 includes a process cartridge 50 that transfers an image onto the surface of the sheet S transported from the paper feed unit 3, and an exposure unit 41 that exposes the surface of a photosensitive drum 53 of the process cartridge 50.

[0043] The process cartridge 50 is detachably mounted in the main body housing 2. The process cartridge 50 includes a drum unit 51 and a developing unit 55, and is mounted in the main body housing 2 with the developing unit 55 attached to the drum unit 51. The process cartridge 50 mounted in the main body housing 2 is disposed above the paper feed unit 3 in the main body housing 2.

[0044] The drum unit 51 has a photosensitive drum 53, a charging roller 54, and a transfer roller 42. The developing unit 55 has a toner storage chamber 57, a supply roller 58, and a developing roller 59. The drum unit 51 supports a pinch roller 35b.

[0045] 3, the opening 2A of the main body housing 2 is configured to allow the process cartridge 50 to pass through, and by moving the front cover 21 to the first open position, the process cartridge 50 can be easily attached to and detached from the main body housing 2 through the opening 2A. The process cartridge 50 attached to the main body housing 2 is removed from the main body housing 2 when, for example, the process cartridge 50 needs to be replaced or when a sheet S becomes jammed.

[0046] The process cartridge 50 is attached to the main body housing 2 by inserting the drum unit 51 and the developing unit 55 attached to the drum unit 51 together into the main body housing 2. The process cartridge 50 is detached from the main body housing 2 by removing the drum unit 51 and the developing unit 55 attached to the drum unit 51 together from the main body housing 2.

[0047] When the process cartridge 50 is attached to the main body casing 2, the photosensitive drum 53 is disposed in such a position that the rotation axis X of the photosensitive drum 53 is aligned in the left-right direction. The photosensitive drum 53 has a metal drum shaft 53a that extends along the rotation axis X. The photosensitive drum 53 rotates around the rotation axis X.

[0048] When the process cartridge 50 is attached to the main body casing 2, the developing roller 59 is disposed in such a position that the rotation axis Y of the developing roller 59 is aligned in the left-right direction. The developing roller 59 rotates around the rotation axis Y. The rotation axis Y of the developing roller 59 is disposed parallel to the rotation axis X of the photosensitive drum 53.

[0049] The exposure unit 41 is equipped with a laser diode, a polygon mirror, a lens, a reflecting mirror, etc., and exposes the surface of the photosensitive drum 53 by irradiating the photosensitive drum 53 with laser light based on image data input to the image forming device 1.

[0050] Toner that will become a developer is stored in toner storage chamber 57. The toner stored in toner storage chamber 57 is sent to supply roller 58 while being stirred by stirring members 571 and 572. Supply roller 58 further supplies the toner sent from toner storage chamber 57 to development roller 59.

[0051] The developing roller 59 is disposed in close contact with the supply roller 58, and carries positively charged toner supplied from the supply roller 58. A developing bias is applied to the developing roller 59 by a bias application means (not shown).

[0052] The photosensitive drum 53 is disposed adjacent to the developing roller 59. The surface of the photosensitive drum 53 is uniformly charged by the charging roller 54 and then exposed by the exposure unit 41. The exposed portion of the photosensitive drum 53 has a lower potential than the other portions, and an electrostatic latent image based on the image data is formed on the photosensitive drum 53. Then, positively charged toner is supplied from the developing roller 59 to the surface of the photosensitive drum 53 on which the electrostatic latent image has been formed, thereby visualizing the electrostatic latent image into a toner image.

[0053] The transfer roller 42 is disposed opposite the photosensitive drum 53, and a transfer bias is applied to it by a bias application means (not shown). With the transfer bias applied to the surface of the transfer roller 42, the sheet S is conveyed while being sandwiched between the photosensitive drum 53 on which the toner image has been formed and the transfer roller 42, whereby the toner image formed on the surface of the photosensitive drum 53 is transferred to the surface of the sheet S. The sheet S onto which the toner image has been transferred is conveyed to the fixing device 6.

[0054] The fixing unit 6 includes a heating roller 61 and a pressure roller 62, and fixes the image transferred onto the sheet S by the process cartridge 50. The heating roller 61 is heated by supplying power from a power source (not shown). The pressure roller 62 is disposed opposite the heating roller 61. One of the heating roller 61 and the pressure roller 62 is biased toward the other by a biasing mechanism (not shown), and the heating roller 61 and the pressure roller 62 are in close contact with each other.

[0055] When the sheet S onto which the toner image has been transferred is conveyed to the fixing device 6, the sheet S is conveyed while being sandwiched between the heating roller 61 and the pressure roller 62, whereby the sheet S is heated and the toner image transferred onto the conveyed sheet S is fixed. In this way, the fixing device 6 fixes the toner image onto the sheet S.

[0056] The fixing device 6 includes a pair of post-fixing conveying rollers 63, and the sheet S on which the toner has been fixed by the fixing device 6 is conveyed to a paper discharge section 7 by the pair of post-fixing conveying rollers 63.

[0057] The paper discharge unit 7 is located downstream of the fixing unit 6 in the sheet transport direction, and discharges the sheet S on which an image has been formed in the image forming unit 5 to the outside of the image forming apparatus 1. The paper discharge unit 7 includes a pair of paper discharge rollers 71 and a paper discharge tray 72. The pair of paper discharge rollers 71 is configured to be able to discharge the sheet S transported from the fixing unit 6 along the transport path P to the outside of the main body housing 2. The paper discharge tray 72 is formed on the top surface of the main body housing 2, and supports the sheet S discharged to the outside of the main body housing 2 by the pair of paper discharge rollers 71.

[0058] [Process cartridge] As shown in Fig. 4, the process cartridge 50 is detachably attached to the main body housing 2, and is housed within the main body housing 2 when attached to the main body housing 2. As described above, the process cartridge 50 includes the drum unit 51 and the developing unit 55. In other words, the drum unit 51 and the developing unit 55 constitute the process cartridge 50. When the process cartridge 50 is attached to the main body housing 2, the drum unit 51 is fixed to the main body housing 2. Furthermore, the developing unit 55 is movable relative to the drum unit 51.

[0059] (drum unit) As shown in FIGS. 4 to 6, the drum unit 51 has a drum frame 52 in addition to the photosensitive drum 53, the charging roller 54, and the transfer roller 42. The drum frame 52 supports the photosensitive drum 53, the charging roller 54, and the transfer roller 42. The photosensitive drum 53, the charging roller 54, and the transfer roller 42 are disposed at the rear end of the drum unit 51 in the front-to-rear direction. The rear end of the drum unit 51 is an example of one end of the drum unit. The front-to-rear direction is an example of a second direction that intersects with the rotation axis of the photosensitive drum.

[0060] The drum frame 52 has a left side plate 521 , a right side plate 522 , an upper plate 523 , a front plate 524 , a discharge port 525 , a connecting portion 526 , a receiving port 527 , a waste toner storage portion 528 , and a blade 529 .

[0061] The left side plate 521 is located at the left end of the drum frame 52, and the right side plate 522 is located at the right end of the drum frame 52. The left side plate 521 and the right side plate 522 extend in the front-rear and up-down directions, and face each other in the left-right direction. The photosensitive drum 53, the charging roller 54, and the transfer roller 42 are located between the left side plate 521 and the right side plate 522.

[0062] The left side plate 521 has a first elongated hole 5211 and a second elongated hole 5212 that penetrate in the left-right direction. The first elongated hole 5211 and the second elongated hole 5212 are elongated holes with their major axes extending in a first direction. The first direction is a direction connecting the rotational axis X of the photosensitive drum 53 and the rotational axis Y of the developing roller 59, and is inclined with respect to the front-to-rear direction. The first direction is a direction intersecting the rotational axis X of the photosensitive drum 53. The first elongated hole 5211 is located at the front end of the left side plate 521, and the second elongated hole 5212 is located rearward of the first elongated hole 5211.

[0063] The right side plate 522 has a first elongated hole 5221 and a second elongated hole 5222 that penetrate in the left-right direction. The first elongated hole 5221 and the second elongated hole 5222 are elongated holes with their major axes oriented in the first direction. The first elongated hole 5221 is located at the front end of the right side plate 522, and the second elongated hole 5222 is located rearward of the first elongated hole 5221.

[0064] The upper plate 523 is located at the upper and front end of the drum frame 52. The upper plate 523 extends in the left-right and front-rear directions, and connects the left side plate 521 and the right side plate 522. The front plate 524 extends downward from the front end of the upper plate 523, and connects the left side plate 521 and the right side plate 522.

[0065] The discharge port 525 opens at the center of the left and right of the upper plate 523. The discharge port 525 penetrates the upper plate 523 in the vertical direction and is formed in a circular shape. The connecting portion 526 is a cylindrical member that extends upward from the peripheral edge of the discharge port 525 on the upper plate 523. The receiving port 527 opens at the upper end of the connecting portion 526. The connecting portion 526 connects the receiving port 527 and the discharge port 525. A cap 80 is attached to the upper end of the connecting portion 526, and the receiving port 527 is closed by the cap 80.

[0066] The discharge port 525, the connecting portion 526, and the receiving port 527 are disposed at the front end portion of the drum unit 51. The front end portion of the drum unit 51 is an example of the other end portion of the drum unit.

[0067] The waste toner storage section 528 is located at the rear end of the drum unit 51. The waste toner storage section 528 is located behind the photosensitive drum 53. The waste toner storage section 528 has an opening 528a at a position facing the photosensitive drum 53. The waste toner storage section 528 is capable of storing waste toner.

[0068] Blade 529 is a plate-like member that contacts the surface of photosensitive drum 53 and extends in the left-right direction. Blade 529 is attached to the periphery of opening 528a in waste toner storage section 528. As photosensitive drum 53 rotates, waste toner adhering to the surface of photosensitive drum 53 is scraped off by blade 529, and the scraped waste toner is stored in waste toner storage section 528 through opening 528a.

[0069] (developing unit) As shown in FIGS. 4 to 7, the developing unit 55 has a developing frame 56 in addition to a supply roller 58 and a developing roller 59. The developing frame 56 supports the supply roller 58 and the developing roller 59. The supply roller 58 and the developing roller 59 are disposed at the rear end of the developing unit 55. A toner storage chamber 57 is formed inside the developing frame 56.

[0070] The developing frame 56 is located inside a space surrounded by a left side plate 521, a right side plate 522, an upper plate 523, and a front plate 524 of the drum frame 52. The developing frame 56 has a left side wall 561, a right side wall 562, an upper wall 563, a front wall 564, a bottom wall 565, and a supply port 566.

[0071] The left side wall 561 is located at the left end of the developing frame 56, and the right side wall 562 is located at the right end of the developing frame 56. The left side wall 561 and the right side wall 562 extend in the front-rear and up-down directions, and face each other in the left-right direction. The supply roller 58 and the developing roller 59 are located between the left side wall 561 and the right side wall 562.

[0072] The left side wall 561 has a first pin 5611 and a second pin 5612 that protrude leftward from the left surface of the left side wall 561. The first pin 5611 is located at the front end of the left side wall 561, and the second pin 5612 is located at the rear end of the left side wall 561. The second pin 5612 is located rearward of the first pin 5611. The second pin 5612 may be the left end of the rotation shaft of the developing roller 59.

[0073] The first pin 5611 and the second pin 5612 are fitted into a first elongated hole 5211 and a second elongated hole 5212, respectively, formed in the left side plate 521 of the drum frame 52. The first pin 5611 and the second pin 5612 are movable along the longitudinal directions of the first elongated hole 5211 and the second elongated hole 5212, respectively.

[0074] The right side wall 562 has a first pin 5621 and a second pin 5622 that protrude rightward from the right surface of the right side wall 562. The first pin 5621 is located at the front end of the right side wall 562, and the second pin 5622 is located at the rear end of the right side wall 562. The second pin 5622 is located rearward of the first pin 5621. The second pin 5622 may be the right end of the rotation shaft of the developing roller 59.

[0075] The first pin 5621 and the second pin 5622 are fitted into a first elongated hole 5221 and a second elongated hole 5222, respectively, formed in the right side plate 522 of the drum frame 52. The first pin 5621 and the second pin 5622 are movable along the longitudinal directions of the first elongated hole 5221 and the second elongated hole 5222, respectively.

[0076] The first pin 5611 and the second pin 5612 move along the longitudinal direction of the first elongated hole 5211 and the second elongated hole 5212, and the first pin 5621 and the second pin 5622 move along the longitudinal direction of the first elongated hole 5221 and the second elongated hole 5222, so that the developing unit 55 can move in the first direction relative to the drum unit 51. This allows the developing roller 59 to move in the first direction relative to the photosensitive drum 53.

[0077] The upper wall 563 is located at the upper end of the developing frame 56. The upper plate 563 extends in the left-right and front-rear directions, and connects the left side wall 561 and the right side wall 562. A supply port 566 opens at the front end and left-right center of the upper wall 563. The supply port 566 communicates with the toner storage chamber 57. The supply port 566 is located at the front end of the developing unit 55 in the front-rear direction. The front wall 564 extends downward from the front end of the upper wall 563, and connects the left side wall 561 and the right side wall 562.

[0078] The bottom wall 565 is located at the lower end of the developing frame 56. The bottom wall 565 extends in the left-right and front-rear directions and connects the left side wall 561 and the right side wall 562. The bottom wall 565 has a first bottom surface 565a, a second bottom surface 565b, a third bottom surface 565c, a fourth bottom surface 565d, and a protruding wall 565e. The first bottom surface 565a, the second bottom surface 565b, the third bottom surface 565c, and the fourth bottom surface 565d are surfaces facing upward of the bottom wall 565 and form the bottom surface of the toner storage chamber 57.

[0079] The first bottom surface 565a and the second bottom surface 565b are located below the supply port 566. The first bottom surface 565a is a bottom surface that extends rearward from the position where the supply port 566 is projected in the up-down direction onto the bottom surface of the toner storage chamber 57, and is formed as an inclined surface that slopes downward as it extends rearward.

[0080] That is, the first bottom surface 565a is an inclined surface that slopes downward as it moves away from the position where the supply port 566 is projected in the vertical direction onto the bottom surface of the toner accommodating chamber 57. The first bottom surface 565a is an inclined surface that slopes downward as it moves closer to the developing roller 59 from the position where the supply port 566 is projected in the vertical direction onto the bottom surface of the toner accommodating chamber 57. The first bottom surface 565a is an example of a first inclined surface.

[0081] The second bottom surface 565b is a bottom surface that extends left and right from the position where the supply port 566 is projected in the up-down direction onto the bottom surface of the toner storage chamber 57, and is formed as an inclined surface that slopes downward toward the left and right. Specifically, the second bottom surface 565b located on the left slopes downward toward the left, and the second bottom surface 565b located on the right slopes downward toward the right.

[0082] That is, the second bottom surface 565b is an inclined surface that slopes downward with increasing distance from the position where the supply port 566 is projected in the vertical direction onto the bottom surface of the toner accommodating chamber 57. The second bottom surface 565b is also an inclined surface that slopes downward with increasing distance along the direction of the rotation axis Y of the developing roller 59 from the position where the supply port 566 is projected in the vertical direction onto the bottom surface of the toner accommodating chamber 57. The second bottom surface 565b is an example of a second inclined surface.

[0083] The third bottom surface 565c is formed to continue to the left and right of the second bottom surface 565b. The third bottom surface 565c is formed as an inclined surface that slopes downward from the front to the rear. The rear end of the third bottom surface 565c is connected to the first bottom surface 565a located behind the third bottom surface 565c.

[0084] The fourth bottom surface 565d extends rearward from the rear end of the first bottom surface 565a. The protruding wall 565e protrudes from the fourth bottom surface 565d toward the inside of the toner accommodating chamber 57, and extends along the direction of the rotational axis Y of the developing roller 59. The stirring members 571 and 572 provided in the toner accommodating chamber 57 are disposed in a portion of the toner accommodating chamber 57 where the fourth bottom surface 565d is located.

[0085] The space surrounded by a left wall 561, a right wall 562, a top wall 563, a front wall 564, and a bottom wall 565 of the developing frame 56 forms a toner storage chamber 57. The rear end of the toner storage chamber 57 is open, and a developing roller 59 is disposed in the open portion of the rear end of the toner storage chamber 57.

[0086] (Compression spring) 4 to 6, the front plate 524 of the drum frame 52 and the front wall 564 of the developing frame 56 face each other in the front-rear direction, and a compression spring 81 is interposed between the front plate 524 and the front wall 564. The compression spring 81 biases the developing frame 56 rearward relative to the drum frame 52.

[0087] The developing frame 56 is movable in a first direction along the longitudinal direction of the first elongated holes 5211, 5221 and the second elongated holes 5212, 5222 by the biasing force of the compression spring 81. When the developing frame 56 moves in the first direction, the developing roller 59 moves closer to the photosensitive drum 53 in the first direction. In other words, the compression spring 81 is a pressing member that presses the developing roller 59 closer to the photosensitive drum 53 in the first direction.

[0088] The developing roller 59 is movable in a first direction relative to the photosensitive drum 53, and the compression spring 81 is configured to press the developing roller 59 toward the photosensitive drum 53 in the first direction, so that if any deviation in the outer diameter of the developing roller 59 occurs, the deviation can be absorbed. This allows the developing roller 59 to rotate smoothly.

[0089] (Positional relationship of receiving inlet, discharge inlet, and supply inlet) 4 to 6, when the process cartridge 50 is attached to the main body housing 2, the discharge port 525 is located above the supply port 566, and the receiving port 527 is located above the discharge port 525. In other words, the receiving port 527, the discharge port 525, and the supply port 566 are arranged in this order from top to bottom.

[0090] The discharge port 525 is formed to have the same size as the receiving port 527, and the supply port 566 is formed to have the same size as the discharge port 525. Furthermore, when the process cartridge 50 is attached to the main body casing 2, the receiving port 527, the discharge port 525, and the supply port 566 are arranged in positions where they at least partially overlap when viewed from above and below, regardless of the position of the developing unit 55 relative to the drum unit 51.

[0091] However, it is also possible to form the discharge port 525 larger than the receiving port 527 and the supply port 566 larger than the discharge port 525, so that, regardless of the position of the developing unit 55 relative to the drum unit 51, when viewed from the top and bottom, the discharge port 525 is located within the range of the supply port 566 and the receiving port 527 is located within the range of the discharge port 525.

[0092] (Sealing material) A seal member 82 is provided between the supply port 566 of the developing frame 56 and the discharge port 525 of the drum frame 52. The seal member 82 is made of an elastic member such as a sponge formed in a circular ring shape that is elastically deformable.

[0093] The lower surface of the seal member 82 contacts the peripheral edge of the supply port 566 in the upper wall 563 of the developing frame 56, and the upper surface of the seal member 82 contacts the peripheral edge of the discharge port 525 in the upper plate 523 of the drum frame 52. In this way, the seal member 82 seals the gap between the supply port 566 and the discharge port 525. The discharge port 525 is also connected to the supply port 566 by the seal member 82.

[0094] The lower surface of the sealing member 82 may be fixed to the peripheral edge of the supply port 566 in the upper wall 563 of the developing frame 56, and the upper surface may be fixed to the peripheral edge of the discharge port 525 in the upper plate 523 of the drum frame 52. Alternatively, the lower surface of the sealing member 82 may be fixed to the peripheral edge of the supply port 566 in the upper wall 563 of the developing frame 56, and the upper surface may be fixed to the peripheral edge of the discharge port 525 in the upper plate 523 of the drum frame 52.

[0095] The seal member 82 is elastically deformable to allow relative movement between the supply port 566 and the discharge port 525. Therefore, even when the developing frame 56 moves with respect to the drum frame 52, causing the supply port 566 and the discharge port 525 to move relatively, the seal between the supply port 566 and the discharge port 525 can be maintained.

[0096] [Front cover and replacement cover] 1 to 4 and 8, the front cover 21 has an opening 21A formed on the upper surface of the front cover 21 when in the first closed position, and penetrating in the vertical direction. The opening 21A is formed in a rectangular shape. The opening 21A is an example of a second opening.

[0097] The main body housing 2 is provided with a supply cover 22 that is provided on the front cover 21 and is movable between a second closed position (position shown in FIG. 2) that closes the opening 21A and a second open position (position shown in FIG. 8) that opens the opening 21A. The supply cover 22 is formed in a rectangular shape that corresponds to the shape of the opening 21A. The supply cover 22 is an example of a second cover.

[0098] The supply cover 22 is located at the rear end of the supply cover 22 and can be moved between a second closed position and a second open position by rotating about a rotation shaft 22a extending in the left-right direction. The supply cover 22 located at the second open position is located rearward of the supply cover 22 located at the second closed position.

[0099] The receiving opening 527 of the drum unit 51 is located below the opening 21A of the front cover 21 when the front cover 21 is in the first closed position, and the opening 21A can communicate with the receiving opening 527. When the front cover 21 is moved to the first closed position and the supply cover 22 is moved to the second open position, the receiving opening 527 is exposed to the outside through the opening 21A (see FIGS. 4 and 8). When the front cover 21 is moved to the first closed position and the supply cover 22 is moved to the second closed position, the opening 21A is closed by the supply cover 22, and the receiving opening 527 is covered from above by the supply cover 22 (see FIGS. 1 and 2).

[0100] [Replenishing toner from a toner container to a process cartridge] 4, in the image forming apparatus, when front cover 21 is in the first closed position, supply cover 22 is moved to the second open position and cap 80 attached to the upper end of connecting portion 526 is removed, thereby exposing receiving port 527 of drum unit 51 to the outside. By exposing receiving port 527 to the outside, toner container 90 can be connected to receiving port 527.

[0101] 9, by connecting a toner container 90 for toner supply to the receiving port 527 exposed to the outside, it is possible to supply toner from the toner container 90 to the toner storage chamber 57 of the process cartridge 50. In this case, the receiving port 527 receives toner from the toner container 90 by being connected to the toner container 90. The toner storage chamber 57 stores the toner supplied from the toner container 90.

[0102] Toner container 90 has a container body 901 that stores toner, and a connection port 902 that can be connected to receiving port 527. When toner container 90 is positioned in a position where connection port 902 is positioned downward, connection port 902 of toner container 90 is connected to receiving port 527 of drum unit 51, and toner stored in container body 901 is replenished to toner storage chamber 57 by its own weight.

[0103] In this case, the toner container 90 is connected to the receiving port 527 of the drum unit 51 when the process cartridge 50 is attached to the main body housing 2 and the drum unit 51 is fixed to the main body housing 2. Therefore, even if the developing unit 55 is configured to be movable relative to the drum unit 51, the toner container 90 can be easily connected to the process cartridge 50.

[0104] Furthermore, if the toner container 90 is directly connected to the developing unit 55, there is a risk that the toner container 90 may be hit hard against the developing unit 55 when connecting the toner container 90, and the photosensitive drum 53 may be damaged by the impacted developing unit 55. However, in this embodiment, this risk can be avoided by connecting the toner container 90 to the receiving port 527 of the drum unit 51.

[0105] Furthermore, the receiving port 527, the discharge port 525, and the supply port 566 are arranged in positions where they at least partially overlap when viewed from the top-bottom direction, which is the direction in which the discharge port 525 and the supply port 566 are connected, so that the toner in the toner container 90 can smoothly flow into the toner storage chamber 57 of the developing unit 55 through the receiving port 527, the discharge port 525, and the supply port 566. This allows the toner to be smoothly replenished from the toner container 90 to the developing unit 55.

[0106] In addition, the photosensitive drum 53 is located at the rear end of the drum unit 51, the receiving port 527 and the discharge port 525 are located at the front end of the drum unit 51, the developing roller 59 is located at the rear end of the developing unit 55, and the supply port 566 is located at the front end of the developing unit 55.

[0107] Therefore, when the image forming apparatus 1 is configured such that the photosensitive drum 53 and the developing roller 59 are located in the center of the main housing 2, the receiving port 527 and the discharge port 525 of the drum unit 51 and the supply port 566 of the developing unit 55 can be located at the front end of the main housing 2. This improves the workability when connecting the toner container 90 to the receiving port 527.

[0108] In addition, the receiving inlet 527, the discharge outlet 525, and the supply inlet 566 can be configured such that the discharge outlet 525 is larger than the receiving inlet 527 and the supply inlet 566 is larger than the discharge outlet 525, so that when viewed from above and below, the discharge outlet 525 is located within the range of the supply inlet 566 and the receiving inlet 527 is located within the range of the discharge outlet 525.

[0109] When configured in this manner, when toner container 90 is connected to receiving port 527 and toner is replenished from toner container 90, the toner does not get caught on the peripheral edges of discharge port 525 and supply port 566, and can flow smoothly into toner storage chamber 57 of development unit 55.

[0110] Furthermore, the surface facing the upper side of bottom wall 565 that forms the bottom surface of toner storage chamber 57 has first bottom surface 565a and second bottom surface 565b that are inclined surfaces that slope downward with increasing distance from the position of supply port 566 projected in the up-down direction onto the bottom surface of toner storage chamber 57. Therefore, toner supplied into toner storage chamber 57 from supply port 566 flows toward the side away from supply port 566, and it is possible to prevent toner from accumulating in one place below supply port 566 within toner storage chamber 57.

[0111] In particular, the first bottom surface 565a is an inclined surface that slopes downward as it approaches the developing roller 59 from the position where the supply port 566 is projected vertically onto the bottom surface of the toner storage chamber 57, and the second bottom surface 565b is an inclined surface that slopes downward as it moves away from the position where the supply port 566 is projected vertically onto the bottom surface of the toner storage chamber 57 along the rotational axis Y of the developing roller 59.

[0112] This allows the toner replenished in the toner storage chamber 57 to flow in the direction from the supply port 566 toward the developing roller 59 and in the direction along the rotational axis Y of the developing roller 59, allowing the toner to be stored uniformly within the toner storage chamber 57.

[0113] The developing unit 55 also has a protruding wall 565e that protrudes from the fourth bottom surface 565d into the toner accommodating chamber 57 and extends along the direction of the rotational axis Y of the developing roller 59. Therefore, when the toner supplied from the supply port 566 into the toner accommodating chamber 57 flows toward the developing roller 59, the toner is temporarily blocked by the protruding wall 565e and spreads in the direction of the rotational axis Y of the developing roller 59, allowing the toner to flow over a wide range within the toner accommodating chamber 57.

[0114] [Modification of sealing member] The seal member 82 can also be formed as a seal member 82A shown in Fig. 10. The seal member 82A has a first portion 821 and a second portion 822 formed in an annular shape. The first portion 821 and the second portion 822 are made of an elastic material that can be elastically deformed, such as a sponge. The first portion 821 and the second portion 822 are arranged so as to overlap in the vertical direction, with the first portion 821 located above the second portion 822.

[0115] The upper surface of the first portion 821 is fixed to the peripheral edge of the discharge port 525 of the upper plate 523 of the drum frame 52. The lower surface of the second portion 822 is fixed to the peripheral edge of the supply port 566 of the upper wall 563 of the developing frame 56. The lower surface of the first portion 821 and the upper surface of the second portion 822 are in contact with each other.

[0116] Sealing member 82A having first portion 821 and second portion 822 seals between supply port 566 and discharge port 525. Discharge port 525 is also connected to supply port 566 by sealing member 82A.

[0117] The first portion 821 and the second portion 822 of the seal member 82A are elastically deformed, thereby allowing relative movement between the supply port 566 and the discharge port 525. Therefore, even when the developing frame 56 moves with respect to the drum frame 52 and the supply port 566 and the discharge port 525 move relative to each other, the seal between the supply port 566 and the discharge port 525 can be maintained.

[0118] Furthermore, since the sealing member 82A is formed separately into the first portion 821 and the second portion 822, by assembling the drum unit 51 with the first portion 821 fixed and the developing unit 55 with the second portion 822 fixed, it is possible to seal the gap between the supply port 566 and the discharge port 525. This improves the workability when assembling the drum unit 51 and the developing unit 55 to form the process cartridge 50. [Explanation of symbols]

[0119] 1. Image forming device 2 Main unit housing 2A (Main body housing) opening 21 Front cover 21A (Front cover) opening 22 Refill cover 50 Process cartridge 51 Drum unit 52 Drum Frame 53 Photosensitive drum 55 Development unit 56 Developing Frame 57 Toner Storage Room 59 Developing roller 81 Compression spring 82, 82A sealing material 90 Toner container 525 Outlet 526 Connecting part 527 Inlet 565 (developing frame) bottom wall 565a 1st bottom 565b 2nd bottom 565c 3rd bottom 565d 4th bottom 565e Projecting wall 566 Supply Inlet 821 (of sealing member 80A) first part 822 (Second part of sealing member 80A) X (photosensitive drum) rotation axis

Claims

1. A main body housing; a drum unit having a photosensitive drum; a developing unit having a developing roller; a supply port provided in the developing unit; a receiving port provided in the drum unit and connected to a toner container for toner supply, for receiving toner from the toner container; a discharge port provided in the drum unit and connected to the supply port; a connecting portion provided in the drum unit and connecting the receiving opening and the discharge opening; a sealing member provided between the supply port and the discharge port, the sealing member being made of an elastically deformable elastic member that allows relative movement between the supply port and the discharge port; the drum unit and the developing unit constitute a process cartridge, an image forming apparatus, characterized in that, when the process cartridge is attached to the main body housing, the receiving port, the discharge port, and the supply port at least partially overlap each other when viewed from above and below;

2. the developing roller is movable relative to the photosensitive drum in a first direction intersecting a rotation axis of the photosensitive drum, The image forming apparatus according to claim 1 , further comprising a pressing member that presses the developing roller toward the photosensitive drum in the first direction.

3. In a second direction intersecting the rotation axis of the photosensitive drum, the photosensitive drum is disposed at one end of the drum unit, and the receiving opening and the discharging opening are disposed at the other end of the drum unit; 2. The image forming apparatus according to claim 1, wherein the developing roller is disposed at one end of the developing unit, and the supply port is disposed at the other end of the developing unit.

4. The discharge port is located above the supply port, The receiving port is located above the discharge port, The discharge port is formed to be the same size as the receiving port or larger than the receiving port, The supply port is formed to be the same size as or larger than the discharge port, 2. The image forming apparatus according to claim 1, wherein, when viewed from above, the discharge port is located within the range of the supply port, and the receiving port is located within the range of the discharge port.

5. the developing unit includes a toner storage chamber that communicates with the supply port and stores the toner supplied from the toner container; 2. The image forming apparatus according to claim 1, wherein the bottom surface of the toner storage chamber has an inclined surface that slopes downward with increasing distance from a position where the supply port is projected in a vertical direction onto the bottom surface.

6. The inclined surface is a first inclined surface that is inclined downward from a position where the supply port is projected in a vertical direction relative to the bottom surface toward the developing roller; 6. The image forming apparatus according to claim 5, further comprising a second inclined surface that slopes downward with increasing distance from a position where the supply port is projected vertically onto the bottom surface along the rotational axis of the developing roller.

7. 7. The image forming apparatus according to claim 5, wherein the developing unit has a protruding wall between the supply port and the developing roller, the protruding wall protruding from the bottom surface of the toner storage chamber into the toner storage chamber and extending along the rotational axis of the developing roller.

8. The sealing member is a first portion fixed to a peripheral portion of the supply port of the developing unit; 2. The image forming apparatus according to claim 1, further comprising: a second portion fixed to a peripheral edge of the discharge port of the drum unit.

9. the main body housing has a first opening through which the process cartridge can pass, a first cover movable between a first closed position that closes the first opening and a first open position that opens the first opening, the first cover having a second opening that can communicate with the receiving port; 2. The image forming apparatus according to claim 1, further comprising: a second cover provided on the first cover and movable between a second closed position that closes the second opening and a second open position that opens the second opening.

10. a drum unit having a photosensitive drum; a developing unit having a developing roller; a supply port provided in the developing unit; a receiving port provided in the drum unit and connected to a toner container for toner supply, for receiving toner from the toner container; a discharge port provided in the drum unit and connected to the supply port; a connecting portion provided in the drum unit and connecting the receiving opening and the discharge opening; a sealing member provided between the supply port and the discharge port, the sealing member being made of an elastically deformable elastic member that allows relative movement between the supply port and the discharge port; the developing unit is attached to the drum unit, A process unit in which, when the developing unit is attached to the drum unit, the receiving opening, the discharge opening, and the supply opening at least partially overlap when viewed from the direction in which the discharge opening and the supply opening are connected.

Images