Developing device and image forming apparatus

Abstract

The present application provides a developing device and an image forming apparatus. The developing device has: first and second conveying members arranged in first and second conveying paths formed one below the other in a gravitational direction to convey developer in a manner that the developer circulates between the first and second conveying paths; a developing member arranged opposite the first conveying path and supplied with developer from the first conveying path; and a drive device that is driven in a state in which a relative speed ratio of a rotational speed of the developing member and a rotational speed of the second conveying member can be changed.

Description

Technical Field

[0001] This disclosure relates to developing apparatus and image forming apparatus. Background Technology

[0002] Japanese Patent Application Publication No. 2009-175768 discloses a developing apparatus comprising: a developing roller having a developing area for conveying toner to an electrostatic latent image developed into a toner image; a developing container having a developing roller housing portion for housing the developing roller, a first stirring chamber disposed obliquely below the developing roller housing portion, and a second stirring chamber adjacent to the developing roller housing portion and disposed above the first stirring chamber; a first stirring member disposed in the first stirring chamber, which stirs and conveys the toner in the first stirring chamber in a predetermined first conveying direction; and a second stirring member disposed in the second stirring chamber, which stirs and conveys the toner in the first stirring chamber in a predetermined first conveying direction. The toner in the second stirring chamber is stirred and conveyed simultaneously in a second conveying direction opposite to the first stirring chamber; and a connecting path is provided to connect the downstream end of the first stirring chamber in the first conveying direction to the upstream end of the second stirring chamber in the second conveying direction for conveying the toner from the downstream end of the first stirring chamber in the first conveying direction to the upstream end of the second stirring chamber in the second conveying direction. The connecting path is located on the side away from the developing roller relative to the rotation axis of the first stirring member, and the portion of the connecting path in contact with the second stirring chamber closest to the developing roller is formed at a position vertically below the axis of the developing roller. In this developing apparatus, a residual developer conveying member is also provided for stirring and conveying the developer retained between the developing roller and the first stirring member. Summary of the Invention

[0003] The purpose of this disclosure is to provide a stable supply of the necessary developer to the developing member in a developing apparatus having a first conveying member and a second conveying member arranged vertically adjacent to each other in the direction of gravity, compared to a device that rotates the developing member and the second conveying member at a fixed speed ratio.

[0004] According to a first aspect of this disclosure, a developing apparatus is provided, comprising: a first conveying member and a second conveying member disposed on a first conveying path and a second conveying path formed vertically in the direction of gravity, such that developer is conveyed in a manner that causes developer to circulate between the first conveying path and the second conveying path; a developing member disposed opposite to the first conveying path and supplied with developer from the first conveying path; and a driving device that drives the developing member in a state capable of changing the relative speed ratio between the rotational speed of the developing member and the rotational speed of the second conveying member.

[0005] According to a second aspect of this disclosure, the driving device drives the developing component and the second conveying component through different power sources.

[0006] According to a third aspect of this disclosure, the drive device includes a clutch mechanism that changes the relative speed ratio between the rotational speed of the developing component and the rotational speed of the second conveying component.

[0007] According to the fourth aspect of this disclosure, the driving device drives the device in such a way that the relative speed ratio between the rotational speed of the first transmission component and the rotational speed of the second transmission component is fixed.

[0008] According to a fifth aspect of this disclosure, the developing apparatus further includes a third conveying component disposed in a third conveying path, which recovers unused developer in the developing component and conveys it to the second conveying path. The driving device is driven in such a manner that the relative speed ratio of the rotational speed of the first conveying component, the rotational speed of the second conveying component, and the rotational speed of the third conveying component is fixed.

[0009] According to the sixth aspect of this disclosure, the driving device is driven in a manner where the relative speed ratio between the rotational speed of the developing component and the rotational speed of the first conveying component is fixed.

[0010] According to the seventh aspect of this disclosure, the developing apparatus further includes a third conveying component that recovers and conveys unused developer in the developing component to the second conveying path, and the driving device drives the device in a manner that the relative speed ratio between the rotational speed of the second conveying component and the rotational speed of the third conveying component is fixed.

[0011] According to the eighth aspect of this disclosure, the developing apparatus further includes a third conveying component, wherein unused developer in the developing component is recycled and conveyed to the second conveying path, and the driving device is driven in a manner that the relative speed ratio of the rotational speed of the developing component, the rotational speed of the first conveying component, and the rotational speed of the third conveying component is fixed.

[0012] According to the ninth aspect of this disclosure, the developing apparatus further includes a third conveying component that recovers and conveys unused developer in the developing component to the second conveying path, and the driving device is driven in a manner that the relative speed ratio between the rotational speed of the first conveying component and the rotational speed of the third conveying component is fixed.

[0013] According to the tenth aspect of this disclosure, the developing apparatus further includes a third conveying component that recovers and conveys unused developer in the developing component to the second conveying path, and a separator of a predetermined height is formed between the second conveying path and the third conveying path.

[0014] According to the eleventh aspect of this disclosure, an image forming apparatus is provided, having the developing apparatus and a latent image carrier disposed opposite to the developing apparatus.

[0015] (Effect)

[0016] According to the first scheme, in a developing apparatus having a first conveying member and a second conveying member arranged vertically adjacent to each other in the direction of gravity, the necessary developer can be stably supplied to the developing member compared to a device that rotates the developing member at the same speed ratio as the second conveying member.

[0017] According to the second scheme, the rotational speeds of the developing unit and the second transport unit can be made independent of each other.

[0018] According to the third scheme, the rotational speeds of the developing unit and the second conveying unit can be made independent of each other, and the number of power sources can be reduced compared to the case where the developing unit and the second conveying unit are driven by separate power sources.

[0019] According to the fourth scheme, an amount of developer corresponding to the amount of developer supplied to the developing unit can be cyclically transferred from the second transfer path to the first transfer path, regardless of the rotational speed of the developing unit.

[0020] According to the fifth scheme, the amount of developer corresponding to the rotational speed of the first conveying component can be recovered to the second conveying path regardless of the rotational speed of the developing component.

[0021] According to the sixth scheme, the required amount of developer can be supplied to the developing unit from the first conveying path according to the rotation speed of the developing unit.

[0022] According to the seventh scheme, the remaining developer in the developing unit can be cyclically conveyed to the first conveying path regardless of the rotational speed of the developing unit.

[0023] According to the eighth scheme, an amount of developer corresponding to the rotational speed of the developing unit can be supplied to the developing unit and recovered to the second transport path.

[0024] According to the ninth scheme, the amount of developer corresponding to the rotational speed of the first conveying unit can be recovered to the second conveying path regardless of the rotational speed of the developing unit.

[0025] According to the tenth scheme, it is possible to prevent the developer that has been recycled to the second transport path from flowing back to the third transport path.

[0026] According to the eleventh embodiment, in a developing apparatus having a first conveying member and a second conveying member arranged vertically adjacent to each other in the direction of gravity, compared with a device that rotates the developing member at the same speed ratio as the second conveying member, the necessary developer can be stably supplied to the developing member. Attached Figure Description

[0027] Figure 1 This is a side view showing the structure of an image forming apparatus according to an embodiment of the present disclosure.

[0028] Figure 2 This is a cross-sectional view of the developing apparatus according to the embodiments of the present disclosure, viewed from the direction extending from the developing apparatus.

[0029] Figure 3 This is a cross-sectional view of the developing apparatus according to the embodiments of this disclosure, viewed from the front side.

[0030] Figure 4 Figure (A) is an example of a driving method of a developing apparatus according to an embodiment of the present disclosure. Figure 4 (B) is a diagram illustrating an example of another driving method of the developing apparatus according to an embodiment of the present disclosure.

[0031] Figure 5 Figure (A) is a diagram illustrating another example of a driving method of a developing apparatus according to an embodiment of the present disclosure. Figure 5 (B) is a diagram illustrating an example of another driving method of the developing apparatus according to an embodiment of the present disclosure.

[0032] Figure 6 Figure (A) is a diagram illustrating another example of the driving method of the developing apparatus according to an embodiment of the present disclosure. Figure 6 (B) is a diagram illustrating an example of another driving method of the developing apparatus according to an embodiment of the present disclosure.

[0033] Figure 7 Figure (A) is a diagram illustrating another example of the driving method of the developing apparatus according to an embodiment of the present disclosure. Figure 7 (B) is a diagram illustrating an example of another driving method of the developing apparatus according to an embodiment of the present disclosure.

[0034] Figure 8 Figure (A) is a diagram illustrating another example of the driving method of the developing apparatus according to an embodiment of the present disclosure. Figure 8Figure (B) is an example illustrating another driving method of the developing apparatus according to an embodiment of the present disclosure.

[0035] Figure 9 Figure (A) is a diagram illustrating another example of the driving method of the developing apparatus according to an embodiment of the present disclosure. Figure 9 (B) is a diagram illustrating an example of another driving method of the developing apparatus according to an embodiment of the present disclosure.

[0036] Figure 10 Figure (A) is a diagram illustrating another example of the driving method of the developing apparatus according to an embodiment of the present disclosure. Figure 10 (B) is a diagram illustrating an example of another driving method of the developing apparatus according to an embodiment of the present disclosure. Detailed Implementation

[0037] Next, embodiments of the present disclosure will be described with reference to the accompanying drawings. Figure 1 The image forming apparatus 10 according to an embodiment of the present disclosure is shown. The image forming apparatus 10 has an image forming apparatus main body 12, and an image forming unit 14, a transfer device 16, a fixing device 18, and a paper feeding device 20 are disposed within the image forming apparatus main body 12. In addition, a recording medium transport path 22 for transporting a recording medium such as paper is formed within the image forming apparatus main body 12.

[0038] The image forming unit 14 employs an electrophotographic method to form an image on a recording medium. The image forming unit 14 may have, for example, four or more image forming units 24. The four image forming units 24 may form toner images of different colors, such as yellow, magenta, cyan, and black.

[0039] Each image forming unit 24 has a photosensitive drum 26. The photosensitive drum 26 is an example of an image holder, which holds the toner image transferred onto the recording medium on its outer peripheral surface while rotating. In addition, the image forming unit 24 is provided with a charging device 28 for charging the photosensitive drum 26, a developing device 30 for developing the charged latent image using a developing agent, and a cleaning device 32 for cleaning the transferred photosensitive drum 26. Furthermore, a light writing device 48 is provided for forming a latent image on the charged photosensitive drum 26.

[0040] The transfer device 16 has an intermediate transfer belt 34. The toner image is transferred from the photosensitive drum 26 to the intermediate transfer belt 34 in one pass through the primary transfer unit 36, and the toner image transferred in the first pass is transferred to the recording medium in the second pass through the secondary transfer unit 38.

[0041] The intermediate transfer belt 34 is supported by multiple support members 40 so that it can rotate. In addition, a support member 42 is provided opposite to the secondary transfer member 38.

[0042] The fixing device 18 uses heat and pressure, for example, to fix the toner image transferred to the recording medium onto the recording medium.

[0043] The paper feeding device 20 includes: a receiving section 44 that receives recording media in a stacked state; and a delivery member 46 that delivers the recording media received in the receiving section 44 toward the recording media delivery path 22.

[0044] The recording medium transport path 22 transports the recording medium from the paper feeder 20 to the secondary transfer unit 38 and the support unit 42, and further transports the recording medium to the fixing unit 18, so as to discharge the recording medium to the outside of the image forming apparatus body 12.

[0045] In the image forming apparatus 10 configured as described above, toner images formed on the outer peripheral surface of the photosensitive drum 26 are transferred onto the intermediate transfer belt 34 in one step. The toner images transferred onto the intermediate transfer belt 34 in one step are transferred onto the recording medium in a second step. The toner images transferred onto the recording medium in a second step are fixed onto the recording medium by the fixing device 18.

[0046] Next, refer to Figure 2 The developing apparatus 30 of this embodiment will be described. It is a two-component developing apparatus that develops a developer composed of a carrier and a toner by stirring the toner to charge it. In the following description, "up" refers to the direction of gravity, "down" refers to the direction of gravity, and "up" refers to the direction of gravity without distinguishing between up and down; or simply "up and down direction." Furthermore, the direction orthogonal to the direction of gravity and extending from which the developing roller 52, the first conveying member 82, the second conveying member 84, etc., described later, extends is referred to as the axial direction. Moreover, the side of the first conveying path 62 where the developer supply port 70 is formed, described later... Figure 3 The left side of the paper is conveniently referred to as the supply end side, and the side of the lower section of the second conveying path 64 that is formed, namely the right side of the paper, is referred to as the discharge end side.

[0047] The developing apparatus 30 is disposed opposite to the photosensitive drum 26, which serves as an image holder. The developing apparatus 30 has a developing apparatus body 50 shaped like a developing apparatus housing. Inside the developing apparatus body 50, a developing roller 52, serving as a developing component, is disposed opposite to the photosensitive drum 26. The developing roller 52 includes: a magnetic roller 54 for forming a uniform magnetic field in the axial direction; and a developing sleeve 56 rotatably mounted on the outer periphery of the magnetic roller 54. The magnetic roller 54 is fixed to the developing apparatus body 50 within the developing sleeve 56. The developing sleeve 56 is supported by a cylindrical component made of a non-magnetic material, allowing it to rotate freely relative to the developing apparatus body 50. On the developing apparatus body 50, above the developing roller 52, a layer thickness limiting member 58 is fixed to limit the layer thickness of the developer opposite to the developing sleeve 56. The layer thickness limiting member 58 is formed of a metal plate. The toner adhering to the periphery of the developing sleeve 56 moves to the latent image formed on the photosensitive drum 26 after its layer thickness is limited by the layer thickness limiting member 58.

[0048] The developing apparatus body 50 is divided internally by a partition wall 60 that vertically separates its interior along the direction of gravity, and a first conveying path 62 and a second conveying path 64 are respectively provided, forming vertically along the direction of gravity. The upper surface of the partition wall 60, which has an arc-shaped cross-section, constitutes the lower surface of the first conveying path 62. Furthermore, the lower surface of the partition wall 60, which has an arc-shaped cross-section, constitutes the upper surface of the second conveying path 64. The first conveying path 62 and the second conveying path 64 have the same axial length and extend axially. The developing roller 52 is disposed opposite to a developer supply port 66 formed axially along the first conveying path 62, and developer is supplied from the first conveying path 62.

[0049] like Figure 3 As shown, the upper surface 68 of the developing apparatus body 50 is also the upper surface of the first transport path 62, but a developer supply port 70 is provided on the supply end side at the upper part of the first transport path 62. A first connecting port 72 is formed on the lower side of the developer supply port 70 in the gravity direction of the partition wall 60. A second connecting port 74 is also provided on the partition wall 60 at a position closer to the discharge end than the first connecting port 72. In addition, an upper discharge port 76 is provided on the partition wall 60 near the discharge end. Although the bottom surface 78 of the developing apparatus body 50 is also the bottom surface of the second transport path 64, a lower discharge port 80 is formed at the position closest to the discharge end.

[0050] In the first transport path 62 and the second transport path 64, a first transport component 82 and a second transport component 84 are respectively arranged in a rotatable manner. The first transport component 82 and the second transport component 84 are used to stir the developer between the first transport path 62 and the second transport path 64 and transport it in a cyclic manner.

[0051] like Figure 2 As shown, a third conveying path 86 is provided obliquely below the developing roller 52 in the direction of gravity for recycling the developer remaining in the developing roller 52 back to the second conveying path 64. A third conveying member 88 is rotatably arranged on this third conveying path 86.

[0052] like Figure 3 As shown, the first conveying component 82, the second conveying component 84, and the third conveying component 88 have shaft centers 90, 92, and 94, respectively. The feed end side of the shaft center 90 of the first conveying component 82 is supported on the upper part of the feed end side of the developing apparatus body 50 by a first upper bearing B1, and the discharge end side is supported on the upper part of the discharge end side of the developing apparatus body 50 by a second upper bearing B2. Similarly, the feed end side of the shaft center 92 of the second conveying component 84 is supported on the lower part of the feed end side of the developing apparatus body 50 by a first lower bearing B3, and the discharge end side is supported on the lower part of the discharge end side of the developing apparatus body 50 by a second lower bearing B4. Here, the second upper bearing B2 supporting the discharge end side of the shaft center 90 of the first conveying component 82 and the second lower bearing B4 supporting the discharge end side of the shaft center 92 of the second conveying component 84 are positioned axially in the same direction.

[0053] In addition, in the first conveying component 82, the second conveying component 84, and the third conveying component 88, there are spiral-shaped conveying blades 96, 98, and 100 that are inclined in the same direction around the shaft centers 90, 92, and 94, respectively.

[0054] The conveying blades 96 of the first conveying component 82 are formed around the axis center 90 between the first connecting port 72 and the second connecting port 74. The conveying blades 98 of the second conveying component 84 are also formed around the axis center 92 between the first connecting port 72 and the second connecting port 74.

[0055] Furthermore, on the first conveying component 82, in the portion between the second connecting port 74 and the upper discharge port 76, there are a discharge conveying blade 102 whose blade inclination direction is opposite to that of the conveying blade 96, an adjusting blade 104 whose inclination direction is the same as that of the conveying blade 96, and an upper discharge blade 106 whose blade inclination direction is the same as that of the discharge conveying blade 102 and whose blade radial length is shorter. The discharge conveying blade 102 is formed such that a portion of the blade reaches the second connecting port 74. The upper discharge blade 106 is disposed within an upper discharge space 108, which is formed between an upwardly projecting protrusion of the partition wall 60 and a downwardly projecting protrusion formed from the upper surface of the first conveying path 62, and the dimensions of the upper discharge space 108 in both the vertical and width directions are smaller than those of the first conveying path 62.

[0056] Additionally, on the second conveying component 84, a developer return blade 110 with its blades tilted in the opposite direction to the conveying blade 98, and a lower discharge blade 112 with its blades tilted in the same direction as the conveying blade 98, are provided in the portion between the second connecting port 74 and the lower discharge port 80. The lower discharge blade 112 is disposed within a lower discharge space 114, which is formed between a downwardly protruding portion of the partition wall 60 and an upwardly protruding portion formed by the bottom surface of the second conveying path 64. The dimensions of the lower discharge space 114 in both the vertical and width directions are smaller than those of the second conveying path 64.

[0057] With the above structure, the developer supplied from the developer supply port 70 falls downwards in the direction of gravity in the first conveying path 62 and is supplied to the second conveying path 64 through the first connecting port 72. It is then conveyed in the second conveying path 64 by the second conveying member 84 towards the discharge end, reaching a point near the lower end of the second connecting port 74. The developer conveyed to the lower end of the second connecting port 74 is obstructed from its flow towards the discharge end by the developer return blade 110 and collides with the developer further conveyed from the supply end side within the second conveying path 64. As a result, the developer near the lower end of the second connecting port 74 is pushed upwards in the direction of gravity and fed into the first conveying path 62 through the second connecting port 74.

[0058] The developer fed into the first conveying path 62 is conveyed by the conveying blades 96 of the first conveying component 82 towards the first connecting port 72, i.e., the replenishment end direction, while simultaneously being supplied to the developing roller 52 from the developer supply port 66. The developer that is not supplied to the developing roller 52 and remains on the first conveying path 62 is conveyed by the first conveying component 82 to the first connecting port 72, where it falls downwards in the direction of gravity and is then supplied to the second conveying path 64 again, repeating the above cycle.

[0059] Additionally, a portion of the developer fed from the second conveying path 64 into the first conveying path 62 via the second connecting port 74 is conveyed towards the discharge end via the discharge conveying blade 102, and then pushed back towards the replenishment end by the adjusting blade 104 so as not to discharge more than a predetermined amount of developer. The remaining developer that is not returned towards the replenishment end by the adjusting blade 104 is conveyed towards the discharge end via the upper discharge blade 106 in the upper discharge space 108, and falls downward in the direction of gravity from the upper discharge outlet 76, and is discharged into the lower discharge space 114 of the second conveying path 64. The remaining developer discharged into the lower discharge space 114 is further conveyed towards the discharge end via the lower discharge blade 112, and is finally discharged from the lower discharge outlet 80 to the outside of the developing apparatus body 50.

[0060] Thus, the upper discharge port 76, the lower discharge port 80, the discharge conveyor blade 102, the adjusting blade 104, the upper discharge blade 106, the upper discharge space 108, and the lower discharge blade 112 constitute a developer discharge structure that discharges the remaining developer discharged from the first conveyor path 62 to the outside through the second conveyor path 64.

[0061] On the other hand, the developer remaining after development, which is supplied to the developing roller 52 from the first conveying path 62, is stripped from the developing roller 52 to the third conveying path 86, and further recovered and conveyed from the third conveying path 86 to the second conveying path 64. It is then mixed and stirred by the second conveying component 84 together with new developer supplied by a developer replenishment device (not shown). Figure 3 As indicated by the arrow, a flow of developer can be made that pushes the developer from the second connection port 74 to the first conveying path 62 at the discharge end of the developing apparatus body 50, and then supplies it again from the first conveying member 82 to the developing roller 52.

[0062] Here, the positional relationship between the developing roller 52, the second conveying component 84, and the third conveying component 88 is explained. For example... Figure 2 As shown, the axis center 92 of the second conveying member 84 is positioned above the axis center 94 of the third conveying member 88 in the direction of gravity. Furthermore, the axis centers 92 of both the second and third conveying members 84 are positioned below the axis center of the developing roller 52 in the direction of gravity. Additionally, the axis center 90 of the first conveying member 82 is positioned above the axis center of the developing roller 52 in the direction of gravity.

[0063] Therefore, since the diameter of the third conveying component 88 is smaller than the diameter of the second conveying component 84, the positional relationship between the bottom surface 78 of the second conveying path 64 and the bottom surface of the third conveying path 86 can be such that they are at the same height in the direction of gravity, or the bottom surface of the second conveying path 64 is slightly higher or slightly lower than the bottom surface of the third conveying path 86. Furthermore, in this embodiment, an example has been described where the axis center 92 of the second conveying component 84 is positioned above the axis center 94 of the third conveying component 88 in the direction of gravity. However, as long as the diameters of the second and third conveying components 84 are appropriately selected, and the bottom surfaces of the second and third conveying paths 64 and 86 are at the same vertical height, the axis center 92 of the second conveying component 84 can also be at the same height as the axis center 94 of the third conveying component 88 or slightly lower in the direction of gravity.

[0064] Furthermore, a pre-set height partition 116 is formed between the second transport path 64 and the third transport path 86. This partition 116 is a plate-like wall protruding axially from near the bottom surface of the second transport path 64 and the bottom surface of the third transport path 86 towards the upward direction of gravity. The upper end 118 of the partition 116 is positioned upward in the direction of gravity beyond the imaginary straight line connecting the axis center 92 of the second transport path 84 and the axis center 94 of the third transport path 88. The height of the partition 116 in the direction of gravity can be any height, provided it allows the developer to be transported from the third transport path 86 to the second transport path 64 via the third transport path 88 and prevents the developer transported from the third transport path 86 to the second transport path 64 from returning to the third transport path 86.

[0065] Furthermore, the separator 116 between the second transport path 64 and the third transport path 86, relative to allowing the developer to be transported from the third transport path 86 to the second transport path 64 by the third transport member 88, can be any component as long as it has the function of preventing or stopping the developer transported from the third transport path 86 to the second transport path 64 from returning to the third transport path 86. This is possible as long as the plate with a free end in the direction of gravity, the opening formed in the separator 116, etc., allow the developer to flow in one direction.

[0066] Next, refer to Figure 4 (A) Figure 4 (B) describes the driving methods of the developing roller 52, the first conveying member 82, the second conveying member 84, and the third conveying member 88 in the developing apparatus 30 with the above-described structure. Figure 4 In (A), the developing apparatus 30 includes a drive unit 120 that drives the developing roller 52 by changing the relative speed ratio of the rotational speed of the developing roller 52 and the rotational speed of the second conveying member 84. The drive unit 120 drives the developing roller 52 and the second conveying member 84 by at least two separate power sources, including a first power source M1 and a second power source M2. That is, the developing roller 52 is driven by the first power source M1, and conversely, the second conveying member 84 is driven by the second power source M2.

[0067] Therefore, these independent first power sources M1 and second power sources M2 can drive the developing roller 52 and the second conveying component 84 while changing the rotation speed of the developing roller 52 and the second conveying component 84 independently.

[0068] In addition, such as Figure 4 As shown in (B), the drive unit 120 may also have clutch mechanisms C1 and C2. Figure 4In (B), the developing roller 52 and the second conveying component 84 are driven by the same power source M3 via clutch mechanisms C1 and C2. By using the clutch mechanisms C1 and C2, the combination of the rotational speed of the developing roller 52 and the rotational speed of the first conveying component 82 and the second conveying component 84 can be changed independently.

[0069] Figure 5 (A) Figure 5 (B) represents another example of the driving method of the developing roller 52, the first conveying component 82, the second conveying component 84, and the third conveying component 88 in the developing apparatus 30 with the above structure. Figure 5 The drive unit 120A shown in (A) and as Figure 4 Similarly, in (A), the developing roller 52 and the second conveyor 84 are driven by separate power sources M1 and M2. In addition, the first conveyor 82 and the second conveyor 84 are driven by the same power source M2. Thus, the speed ratio of the first conveyor 82 and the second conveyor 84 is fixed. On the other hand, the developing roller 52 driven by the first power source M1 and the first conveyor 82 and the second conveyor 84 driven by the second power source M2 are driven in a state where their speed ratio can be changed independently of each other.

[0070] exist Figure 5 In (B), the drive unit 120A drives the developing roller 52, the first conveying component 82, and the second conveying component 84 via clutch mechanisms C1 and C2 through the same power source M3. Clutch mechanism C1 is disposed between the power source M3 and the developing roller 52, and clutch mechanism C2 is disposed between the power source M3 and the first conveying component 82 and the second conveying component 84. By using clutch mechanisms C1 and C2, the combination of the rotational speed of the developing roller 52 and the rotational speeds of the first conveying component 82 and the second conveying component 84 can be changed independently.

[0071] Figure 6 (A) Figure 6 (B) shows another example of the driving method of the developing roller 52, the first conveying member 82, the second conveying member 84, and the third conveying member 88 in the developing apparatus 30 with the above structure. Figure 6 The drive unit 120B shown in (A) and Figure 4Similarly, (A) drives the developing roller 52 and the second conveyor 84 via separate power sources M1 and M2. Furthermore, the first conveyor 82, the second conveyor 84, and the third conveyor 88 are driven using the same power source M2. Thus, the rotational speed ratios of the first conveyor 82, the second conveyor 84, and the third conveyor 88 are fixed. On the other hand, the combination of rotational speeds of the developing roller 52 driven by the first power source M1 and the first conveyor 82, the second conveyor 84, and the third conveyor 88 driven by the second power source M2 can be varied independently.

[0072] exist Figure 6 In (B), the drive unit 120B drives the developing roller 52, the first conveying component 82, the second conveying component 84, and the third conveying component 88 from the same power source M3 via clutch mechanisms C1 and C2. Clutch mechanism C1 is disposed between the power source M3 and the developing roller 52, and clutch mechanism C2 is disposed between the power source M3 and the first conveying component 82, the second conveying component 84, and the third conveying component 88. By using clutch mechanisms C1 and C2, the combination of the rotational speed of the developing roller 52 and the rotational speeds of the first conveying component 82, the second conveying component 84, and the third conveying component 88 can be changed independently.

[0073] Figure 7 (A) Figure 7 (B) represents another example of the driving method of the developing roller 52, the first conveying component 82, the second conveying component 84, and the third conveying component 88 in the developing apparatus 30 with the above structure. Figure 7 The drive unit 120C shown in (A) and Figure 4 Similarly, (A) drives the developing roller 52 and the second conveying member 84 via separate power sources M1 and M2. Furthermore, the developing roller 52 and the first conveying member 82 are driven by the same power source M1. Thus, the speed ratio between the developing roller 52 and the first conveying member 82 is fixed. On the other hand, the drive is performed in a state where the combination of the speeds of the developing roller 52 and the first conveying member 82 driven by the first power source M1, and the combination of the speeds of the second conveying member 84 driven by the second power source M2, can be changed independently of each other.

[0074] exist Figure 7 In (B), the drive unit 120C drives the developing roller 52, the first conveying component 82, and the second conveying component 84 from the same power source M3 via clutch mechanisms C1 and C2. Clutch mechanism C1 is disposed between the power source M3 and the developing roller 52 and the first conveying component 82, and clutch mechanism C2 is disposed between the power source M3 and the second conveying component 84. By using clutch mechanisms C1 and C2, the combination of the rotational speeds of the developing roller 52 and the first conveying component 82 and the second conveying component 84 can be changed independently.

[0075] Figure 8 (A) Figure 8 (B) shows another example of the driving method of the developing roller 52, the first conveying member 82, the second conveying member 84, and the third conveying member 88 in the developing apparatus 30 with the above structure. Figure 8 The drive unit 120D shown in (A) and Figure 4 Similarly, in (A), the developing roller 52 and the second conveyor 84 are driven by separate power sources M1 and M2. Furthermore, the developing roller 52 and the first conveyor 82 are driven by the same power source M1, and the second conveyor 84 and the third conveyor 88 are driven by the same power source M2. Thus, the speed ratio between the developing roller 52 and the first conveyor 82 is fixed, and the speed ratio between the second conveyor 84 and the third conveyor 88 is fixed. On the other hand, the driving is performed in a state where the combination of the speeds of the developing roller 52 and the first conveyor 82 driven by the first power source M1, and the speeds of the second conveyor 84 and the third conveyor 88 driven by the second power source M2, can be changed independently.

[0076] exist Figure 8 In (B), the drive unit 120D drives the developing roller 52, the first conveying component 82, the second conveying component 84, and the third conveying component 88 via clutch mechanisms C1 and C2 through the same power source M3. Clutch mechanism C1 is positioned between the power source M3 and the developing roller 52 and the first conveying component 82, while clutch mechanism C2 is positioned between the power source M3 and the second conveying component 84 and the third conveying component 88. By using clutch mechanisms C1 and C2, the combination of the rotational speeds of the developing roller 52 and the first conveying component 82, and the rotational speeds of the second conveying component 84 and the third conveying component 88 can be changed independently.

[0077] Figure 9 (A) Figure 9 (B) shows another example of the driving method of the developing roller 52, the first conveying member 82, the second conveying member 84, and the third conveying member 88 in the developing apparatus 30 with the above structure. Figure 9 The drive unit 120E shown in (A) and Figure 4 Similarly, in (A), the developing roller 52 and the second conveyor 84 are driven by separate power sources M1 and M2. In addition, the developing roller 52, the first conveyor 82, and the third conveyor 88 are driven by the same power source M1, while only the second conveyor 84 is driven by the other power source M2. Therefore, the rotational speed ratio of the developing roller 52, the first conveyor 82, and the third conveyor 88 is fixed. On the other hand, the driving is performed in a state where the combination of the rotational speeds of the developing roller 52, the first conveyor 82, and the third conveyor 88 driven by the first power source M1 and the rotational speed of the second conveyor 84 driven by the second power source M2 can be changed independently.

[0078] exist Figure 9 In (B), the drive unit 120E drives the developing roller 52, the first conveyor 82, the second conveyor 84, and the third conveyor 88 via clutch mechanisms C1 and C2 through the same power source M3. Clutch mechanism C1 is disposed between the power source M3 and the developing roller 52, the first conveyor 82, and the third conveyor 88, while clutch mechanism C2 is disposed between the power source M3 and the second conveyor 84. By using clutch mechanisms C1 and C2, the combination of the rotational speeds of the developing roller 52, the first conveyor 82, the third conveyor 88, and the second conveyor 84 can be changed independently.

[0079] Figure 10 (A) Figure 10 (B) shows another example of the driving method of the developing roller 52, the first conveying member 82, the second conveying member 84, and the third conveying member 88 in the developing apparatus 30 with the above structure. Figure 10 The drive unit 120F shown in (A) and Figure 4 Similarly, (A) drives the developing roller 52 and the second conveyor 84 via separate power sources M1 and M2. In addition, the first conveyor 82 and the third conveyor 88 are driven by another identical power source M3. Thus, the speed ratio of the first conveyor 82 and the third conveyor 88 is fixed. On the other hand, the drive is performed in a state where the combination of the speed of the developing roller 52 driven by the first power source M1, the speed ratio of the second conveyor 84 driven by the second power source M2, and the speeds of the first conveyor 82 and the third conveyor 88 driven by the third power source M3 can be changed independently.

[0080] exist Figure 10 In (B), the drive unit 120F drives the developing roller 52, the first conveyor 82, the second conveyor 84, and the third conveyor 88 from the same power source M4 via clutch mechanisms C1, C2, and C3. Clutch mechanism C1 is located between the power source M4 and the developing roller 52, clutch mechanism C2 is located between the power source M4 and the second conveyor 84, and clutch mechanism C3 is located between the power source M4 and the first and third conveyor components 82 and 88. By using clutch mechanisms C1, C2, and C3, the rotational speed of the developing roller 52, the rotational speed of the second conveyor 84, and the combination of the rotational speeds of the first and third conveyor components 82 can be changed independently.

[0081] Furthermore, the first power source M1, the second power source M2, the third power source M3, and the power source M4 each include a stepper motor (not shown) and a gear mechanism for adjusting the speed, and are disposed within the main body 12 of the image forming apparatus. They are controlled / driven by a control device (not shown) that controls the operation of each part of the image forming apparatus 10. Additionally, the control device includes a CPU (not shown), a memory, a storage device, and a communication interface. The CPU is a microprocessor for control, which controls the operation of each part of the image forming apparatus based on a control program stored in the storage device.

[0082] In addition, in the above embodiments, processor refers to processor in a broad sense, including general-purpose processors (such as CPU: Central Processing Unit, etc.) and dedicated processors (such as GPU: Graphics Processing Unit, ASIC: Application Specific Integrated Circuit, FPGA: Field Programmable Gate Array, programmable logic devices, etc.).

[0083] Furthermore, the actions of the processor in the above embodiments can be performed not only by a single processor, but also by multiple processors located in physically separate positions working together. Additionally, the order of the processor's actions is not limited to the order described in the above embodiments and can be changed as needed.

Claims

1. A developing apparatus comprising: A first conveying component and a second conveying component are configured on a first conveying path and a second conveying path formed vertically in the direction of gravity, so as to convey the developer in a manner that the developer circulates between the first conveying path and the second conveying path. A developing unit is configured opposite to the first transport path and is supplied with developer from the first transport path; as well as The driving device drives the first conveying member in a fixed relative speed ratio to the second conveying member, and also drives it in a state where the relative speed ratio between the developing member and the second conveying member can be changed. The first conveying component has discharge conveying blades in the part between the connecting port of the first conveying path that pushes the developer upward and the discharge port for discharging the developer to the outside, with the blades tilted in the opposite direction to the conveying blades of the first conveying component.

2. The developing apparatus according to claim 1, wherein, The driving device drives the developing component and the second conveying component through different power sources.

3. The developing apparatus according to claim 1, wherein, The drive device includes a clutch mechanism that changes the relative speed ratio between the rotational speed of the developing component and the rotational speed of the second conveying component.

4. The developing apparatus according to claim 1, wherein, The developing apparatus also includes a third conveying component disposed in a third conveying path, which recovers and conveys unused developer from the developing component back to the second conveying path. The drive device is driven in a manner that the relative speed ratio of the rotational speed of the first transmission component, the rotational speed of the second transmission component, and the rotational speed of the third transmission component is fixed.

5. The developing apparatus according to claim 2 or 3, wherein, The developing apparatus also includes a third conveying component that recovers and conveys unused developer from the developing component to the second conveying path. The drive device is driven in a manner that the relative speed ratio between the rotational speed of the first transmission component and the rotational speed of the third transmission component is fixed.

6. The developing apparatus according to any one of claims 1 to 3, wherein, The developing apparatus also includes a third conveying component disposed in a third conveying path, which recovers and conveys unused developer from the developing component to the second conveying path. A pre-set height separating component is formed between the second transmission path and the third transmission path.

7. An image forming apparatus comprising: The developing apparatus according to any one of claims 1 to 6; and The latent image carrier is configured opposite to the developing apparatus.

Images