Developing device

Abstract

To improve the accuracy of detecting the amount of developer remaining in a developing device.SOLUTION: A developing device comprises: a developer storage unit; a conveying member that is disposed inside the storage unit, has a shank rotating about a rotation axis and a sheet connected to the shank, and conveys developer with the rotation of the sheet; and a detection unit that includes first and second conductive members provided in the storage unit and detects capacitance according to the amount of developer between the conductive members. A storage unit frame body is formed of a first inner wall surface provided with the first conductive member and a second inner wall surface intersecting and adjacent to the first inner wall surface and provided with the second conductive member, and has a recess depressed from the inside toward the outside of the storage unit. In the posture during image formation, the first inner wall surface is directed downward, and the second inner wall surface is directed upward and is at an inclination angle equal to or more than the angle of repose of the developer. An intersection of a first virtual line passing through the first inner wall surface and a second virtual line passing through the second inner wall surface is below the rotation axis.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] The present invention relates to a developing device. [Background technology]

[0002] Conventionally, in electrophotographic image forming apparatuses using an electrophotographic image forming process, a developing container configured to agitate toner in a toner (developer) storage section has been adopted. A toner cartridge, which is an example of a developing container, has a developer storage chamber that stores toner for image formation and a developing chamber that develops the image, and image formation is realized by transporting toner from the developer storage chamber to the developing chamber.

[0003] To notify the user of a decrease in the amount of toner due to image formation, a toner cartridge is provided with a remaining amount detection unit that detects the amount of remaining toner. The remaining amount detection unit detects the amount of toner transported to the cartridge and calculates the total remaining amount, which is the sum of the remaining toner amounts in the developer storage chamber and the developing chamber. In particular, to notify the user of a decrease in the remaining toner amount, there is a need for improved accuracy in detecting the remaining amount when the toner is low.

[0004] To ensure the circulation of toner within the toner cartridge, a conveying member is provided within the toner storage unit. The conveying member is composed of a flexible, elastic agitating member and a shaft, and is rotatably supported within the toner cartridge. In this configuration, a method has been proposed in which the agitating member pumps up and conveys toner to a remaining toner amount detection unit located above the rotation axis of the conveying member, thereby detecting the remaining toner amount (Patent Document 1).

[0005] However, with this configuration, because the agitator assumes a nearly horizontal position when passing through the remaining toner amount detection unit, when the remaining toner is low and higher detection accuracy is required, some of the toner being transported as it passes through the remaining toner amount detection unit falls off the agitator from the tip side of the agitator onto the rotation shaft side of the transport member. In this case, the amount of toner pushed into the remaining toner amount detection unit by the tip of the agitator becomes unstable, and as a result, the stability of the calculated remaining toner amount in the toner cartridge may also decrease. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2023-107244 Summary of the Invention [Problem to be solved by the invention]

[0007] When detecting the remaining amount of developer while stirring and transporting the developer inside the developer container, further improvement in detection accuracy is required.

[0008] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to improve the accuracy of detecting the amount of remaining developer in a developing device. [Means for solving the problem]

[0009] The present invention employs the following configuration: A developing device used for image formation in an image forming apparatus, a container for containing a developer; The device has a shaft portion disposed inside the storage portion and supported rotatably around a rotation axis, and a flexible sheet connected to the shaft portion, and the sheet moves in the direction of the rotation axis. a conveying member for conveying the imaging agent; a detection unit including a first conductive member and a second conductive member provided in the container unit, the detection unit detecting an electrostatic capacitance between the first conductive member and the second conductive member according to an amount of developer; Equipped with the frame of the accommodating portion has a recess in a cross section perpendicular to the rotation axis, the recess being formed by a first inner wall surface constituting the accommodating portion, the first inner wall surface being provided with the first conductive member, and a second inner wall surface extending in a direction intersecting the first inner wall surface and adjacent to the first inner wall surface, the second inner wall surface being provided with the second conductive member, the recess recessed from the inside to the outside of the accommodating portion; when the developing device is in a position used for image formation in the image forming apparatus, the first inner wall surface faces downward, and the second inner wall surface faces upward and is configured to have an inclination angle equal to or greater than an angle of repose of the developer, In the cross section, an intersection point where a first virtual line passing through the first inner wall surface and a second virtual line passing through the second inner wall surface intersect is located below the rotation axis. The developing device is characterized by the above. [Effects of the Invention]

[0010] According to the present invention, it is possible to improve the accuracy of detecting the amount of remaining developer in a developing device. [Brief explanation of the drawings]

[0011] [Figure 1A] 10 is a cross-sectional view illustrating a configuration for improving the accuracy of remaining amount detection. [Figure 1B] FIG. 10 is an enlarged cross-sectional view illustrating a configuration for improving the accuracy of remaining amount detection. [Figure 1C] FIG. 10 is an enlarged cross-sectional view illustrating a configuration for improving the accuracy of remaining amount detection. [Figure 2] Schematic cross-sectional view of an image forming apparatus [Figure 3] Cross-sectional view of a process cartridge [Figure 4] Cross-sectional view of an image forming apparatus [Figure 5] Cross-sectional view of an image forming apparatus [Figure 6] Cross-sectional view of an image forming apparatus [Figure 7] Exploded perspective view of the drum unit [Figure 8] FIG. [Figure 9] Assembly perspective view of the process cartridge [Figure 10] A perspective view of a process cartridge [Figure 11] A cross-sectional view of the developing unit illustrating the arrangement of the remaining amount detection unit [Figure 12] 10A and 10B are front and side views of a developing frame for explaining the detection result of a remaining amount detection unit; [Figure 13A] Cross-sectional view illustrating toner transport (low toner remaining) [Figure 13B] Cross-sectional view illustrating toner transport (low toner remaining) [Figure 13C] Cross-sectional view illustrating toner transport (low toner remaining) [Figure 14A] Cross-sectional view illustrating toner transport (large amount of remaining toner) [Figure 14B] Cross-sectional view illustrating toner transport (large amount of remaining toner) [Figure 14C] Cross-sectional view illustrating toner transport (large amount of remaining toner) [Figure 15A] Cross-sectional view illustrating toner transport in different configurations (large amount of remaining toner) [Figure 15B] Cross-sectional view illustrating toner transport in different configurations (large amount of remaining toner) [Figure 15C] Cross-sectional view illustrating toner transport in different configurations (large amount of remaining toner) DETAILED DESCRIPTION OF THE INVENTION

[0012] The best mode for carrying out the present invention will be described in detail below with reference to the drawings and examples. However, the functions, materials, shapes, dimensions, and relative positions of the components described in the examples may be changed as appropriate depending on the configuration of the device to which the invention is applied and various conditions, and unless otherwise specified, the scope of the present invention is not intended to be limited to these.

[0013] [Example 1] Hereinafter, a first embodiment will be described with reference to the drawings. In the first embodiment, an image forming apparatus to which four process cartridges can be detachably attached is exemplified. However, the number of process cartridges attached to the image forming apparatus is not limited to this. It can be set appropriately as needed. In the embodiment described below, a laser beam printer is exemplified as one aspect of the image forming apparatus.

[0014] <General configuration of image forming apparatus> The overall configuration of an electrophotographic image forming apparatus 1 (hereinafter referred to as image forming apparatus 1) according to this embodiment will be described with reference to Fig. 2. Fig. 2 is a schematic cross-sectional view of the image forming apparatus 1. Fig. 3 is a cross-sectional view of a process cartridge 100.

[0015] This image forming apparatus 1 is a four-color full-color laser beam printer that uses an electrophotographic process, and forms a color image on a recording medium 3. The image forming apparatus 1 is of a process cartridge type, and a process cartridge 100 is removably attached to the image forming apparatus main body 2, and a color image is formed on the recording medium 3.

[0016] Here, with respect to the image forming apparatus 1, the side where the front door 10 is provided is referred to as the front (front face), and the side opposite the front is referred to as the back (rear face). When viewing the image forming apparatus 1 from the front, the right side is referred to as the drive side, the left side is referred to as the non-drive side, the upper side is referred to as the top face, and the lower side is referred to as the bottom face. Figure 2 is a cross-sectional view of the image forming apparatus 1 viewed from the non-drive side, with the front side of the page being the non-drive side of the image forming apparatus 1, the right side of the page being the front of the image forming apparatus 1, and the back side of the page being the drive side of the image forming apparatus 1.

[0017] The drive side of the process cartridge 100 is the side where the drum coupling member (photosensitive member coupling member) described later is arranged when viewed in the axial direction of the photosensitive drum, and is the side where the development coupling member described later is arranged when viewed in the axial direction of the developing roller 103 (developer carrier).

[0018] First to fourth process cartridges 100 (100Y, 100M, 100C, 100K) are arranged in the image forming apparatus main body 2. Each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) has a similar electrophotographic process mechanism, but differs in the color and amount of developer (hereinafter referred to as toner). Therefore, in the following, unless a particular distinction is required, the suffixes Y to K will be omitted and the description will be general. The arrangement direction of the first to fourth process cartridges 100 may be, for example, approximately horizontal.

[0019] The first to fourth process cartridges 100 are provided with a drive output section (details A rotational driving force is transmitted from the rollers (details of which will be described later), and bias voltages (charging bias, developing bias, electrostatic residual detection bias, etc.) are supplied from contacts of the image forming apparatus main body 2 (not shown).

[0020] 3, the process cartridge 100 of this embodiment has a photosensitive drum 101 and a drum unit 120 equipped with charging means as process means that acts on the photosensitive drum 101. Here, the drum unit 120 may have not only charging means but also cleaning means as process means.

[0021] The process cartridge 100 also has a developing unit 150 equipped with developing means for developing the electrostatic latent image on the photosensitive drum 101. The drum unit 120 and the developing unit 150 are coupled to each other. A more specific configuration of the process cartridge 100 will be described later.

[0022] The first process cartridge 100Y accommodates yellow (Y) toner in the developing frame and forms a yellow toner image on the surface of the photosensitive drum 101. The second process cartridge 100M accommodates magenta (M) toner in the developing frame and forms a magenta toner image on the surface of the photosensitive drum 101. The third process cartridge 100C accommodates cyan (C) toner in the developing frame and forms a cyan toner image on the surface of the photosensitive drum 101. The fourth process cartridge 100K accommodates black (K) toner in the developing frame and forms a black toner image on the surface of the photosensitive drum 101.

[0023] A laser scanner unit 11 serving as an exposure means is provided above the first to fourth process cartridges 100. This laser scanner unit 11 outputs a laser beam 12 corresponding to image information. The laser beam 12 passes through an exposure window 128 of the process cartridge 100 and scans and exposes the surface of the photosensitive drum 101.

[0024] An intermediate transfer unit 5 serving as a transfer member is provided below the first to fourth process cartridges 100. This intermediate transfer unit 5 has a drive roller 5e and a tension roller 5b, and a flexible transfer belt 5a is stretched over them.

[0025] The lower surface of the photosensitive drum 101 of each of the first to fourth process cartridges 100 contacts the upper surface of the transfer belt 5a. This contact area is the primary transfer portion. A primary transfer roller 5d is provided on the inner side of the transfer belt 5a, facing the photosensitive drum 101.

[0026] A secondary transfer roller 6 is brought into contact with the drive roller 5e via the transfer belt 5a. The contact area between the transfer belt 5a and the secondary transfer roller 6 is the secondary transfer portion.

[0027] A feeding unit 4 is provided below the intermediate transfer unit 5. The feeding unit 4 has a paper feed tray 4a that accommodates a stack of recording media 3, and a paper feed roller 4b.

[0028] 2, a fixing device 7 and a paper discharge device 8 are provided in the upper right corner of the image forming apparatus main body 2, and the top surface of the image forming apparatus main body 2 is a paper discharge tray 9. The toner image on the recording medium 3 is fixed by a fixing means provided in the fixing device 7, and the recording medium 3 is discharged to the paper discharge tray 9.

[0029] <Image formation operation> The steps of the image forming operation for forming a full-color image will be described. The photosensitive drum 101 of each of the first to fourth process cartridges 100 is rotated at a predetermined speed (see arrows in FIG. 3). The transfer belt 5a is also rotated in the forward direction (the direction of arrow B in FIG. 2) relative to the rotation of the photosensitive drum 101 at a speed corresponding to the speed of the photosensitive drum 101.

[0030] The laser scanner unit 11 is also driven. In synchronization with the driving of the laser scanner unit 11, the charging roller 102 in each process cartridge 100 uniformly charges the surface of the photosensitive drum 101 to a predetermined polarity and potential. The laser scanner unit 11 scans and exposes the surface of each photosensitive drum 101 with laser light 12 in accordance with an image signal for each color.

[0031] As a result, an electrostatic latent image corresponding to the image signal for the corresponding color is formed on the surface of each photosensitive drum 101. The formed electrostatic latent image is rotated in the forward direction (arrow C in FIG. 3) relative to the rotation of the photosensitive drum 101. The toner is developed by the developing roller 103 which is rotated at a predetermined speed in the direction (a direction).

[0032] By the electrophotographic image forming process operation as described above, a yellow color toner corresponding to the yellow component of a full-color image is applied to the photosensitive drum 101 of the first process cartridge 100Y. Then, the toner image is primarily transferred onto the transfer belt 5a.

[0033] Similarly, a magenta toner image corresponding to the magenta component of the full-color image is formed on the photosensitive drum 101 of the second process cartridge 100M. Then, this toner image is primarily transferred onto the transfer belt 5a, superimposed on the yellow toner image already transferred onto the transfer belt 5a.

[0034] Similarly, a cyan toner image corresponding to the cyan component of the full-color image is formed on the photosensitive drum 101 of the third process cartridge 100C. Then, this toner image is primarily transferred onto the transfer belt 5a, superimposed on the yellow and magenta toner images already transferred onto the transfer belt 5a.

[0035] Similarly, a black toner image corresponding to the black component of the full-color image is formed on the photosensitive drum 101 of the fourth process cartridge 100K. Then, this toner image is primarily transferred onto the transfer belt 5a, superimposed on the yellow, magenta, and cyan toner images already transferred onto the transfer belt 5a. In this way, a full-color unfixed toner image of four colors, yellow, magenta, cyan, and black, is formed on the transfer belt 5a.

[0036] Meanwhile, the recording media 3 are separated and fed one by one at a predetermined control timing, and the recording media 3 are introduced into a secondary transfer section, which is a contact point between the secondary transfer roller 6 and the transfer belt 5a, at a predetermined control timing.

[0037] As a result, while the recording medium 3 is being transported to the secondary transfer section, the four-color superimposed toner image on the transfer belt 5a is sequentially transferred all at once onto the surface of the recording medium 3. The configuration of the image forming apparatus main body will be described in more detail below.

[0038] The control unit 250 provided in the image forming apparatus 1 is configured by an information processing device having computational resources such as a processor and memory. The components of the image forming apparatus 1 operate based on image information provided from an external device or image information read by a scanner, and perform the image forming operation described above. The control unit 250 controls the components of the image forming apparatus 1 in accordance with a program or user input instructions, thereby executing the image forming operation.

[0039] <Process cartridge installation / removal configuration overview> The cartridge tray 20 (hereinafter referred to as the tray 20) that supports the process cartridges 100 will be described in further detail with reference to Figures 4 to 6. Figure 4 is a cross-sectional view of the image forming apparatus 1 with the front door 10 open and the tray 20 positioned inside the image forming apparatus main body 2. Figure 5 is a cross-sectional view of the image forming apparatus 1 with the front door 10 open and the tray 20 positioned outside the image forming apparatus main body 2, and the process cartridges 100 housed inside the tray 20. Figure 6 is a cross-sectional view of the image forming apparatus 1 with the front door 10 open and the tray 20 positioned outside the image forming apparatus main body 2, and one of the process cartridges 100 has been removed from the tray 20.

[0040] As shown in Figures 4 and 5, the tray 20 is movable in the direction of arrow X1 (pushing direction) and the direction of arrow X2 (pulling out direction), which are substantially horizontal directions, relative to the image forming apparatus main body 2. That is, the tray 20 is provided so that it can be pulled out and pushed into the image forming apparatus main body 2, and is configured so that it can move in a substantially horizontal direction when the image forming apparatus main body 2 is installed on a horizontal surface. Here, the state in which the tray 20 is located inside the image forming apparatus main body 2 with the front door 10 open (the state in Figure 4) is referred to as the inside position. Also, the state in which the tray 20 is located outside the image forming apparatus main body 2 (the state in Figure 5) is referred to as the outside position. In this inside state and outside state, the photosensitive drum 101 and the transfer belt 5a are separated from each other.

[0041] The tray 20 also has a mounting portion 20a at its outer position, into which the first process cartridge 100Y can be removably mounted, as shown in FIG. 6. (The tray 20 also has mounting portions 20a into which the second to fourth process cartridges 100M, 100C, and 100K can be removably mounted.) The process cartridge 100, while positioned in the mounting portion 20a, moves toward the inside of the image forming apparatus main body 2 as the tray 20 moves. In this embodiment, when the front door 10 is closed, the intermediate transfer unit 5 is raised in the direction of arrow Z1 by a link mechanism (not shown) and moves to a position for image formation (a position where the photosensitive drum 101 and the transfer belt 5a contact each other). When the front door 10 is opened, the intermediate transfer unit 5 is lowered in the direction of arrow Z2, separating the photosensitive drum 101 and the transfer belt 5a.

[0042] As described above, the tray 20 allows multiple process cartridges 100 to be moved together to a position inside the image forming apparatus main body 2 where image formation is possible, and also allows them to be pulled out together to the outside of the image forming apparatus main body 2.

[0043] <Overall structure of the process cartridge> The configuration of the process cartridge will be described with reference to Figures 7 to 10. Figure 7 is an exploded perspective view of the drum unit 120. Figure 8 is an exploded perspective view of the development unit 150. Figure 9 is an assembled perspective view of the process cartridge 100 as seen from the drive side, which is one end side in the axial direction of the photosensitive drum 101. Figure 10 is a perspective view of the process cartridge 100 as seen from the drive side.

[0044] The process cartridge 100 includes a photosensitive drum 101 and process means that act on the photosensitive drum 101. The process means includes a charging roller 102 as charging means that charges the photosensitive drum 101, and a developing roller 103 as developing means that develops the latent image formed on the photosensitive drum 101. The process cartridge 100 is divided into a drum unit 120 and a developing unit 150.

[0045] In the following description, the longitudinal direction Y of the drum unit 120 and the developing unit 150 is a direction substantially parallel to the rotation axis a of the photosensitive drum 101 (FIG. 9).

[0046] <Drum unit configuration> As shown in Figures 7 and 9, drum unit 120 is made up of photosensitive drum 101, charging roller 102, and drum frame 121. The charging roller 102 is rotatably supported by driving-side charging roller bearing 126a and non-driving-side charging roller bearing 127a, and is urged toward photosensitive drum 101 (in the direction of arrow F in Figure 3) by pressure springs 126b and 127b. In addition, a driving-side charging roller spacing member 129 and a non-driving-side charging roller spacing member 130 are attached to both longitudinal ends, respectively, and in the initial shipping state, charging roller 102 is spaced apart from photosensitive drum 101. During use, the photosensitive drum 101 rotates, releasing the spaced apart state.

[0047] The photosensitive drum 101 is rotatably supported by a driving side cartridge cover member 122 and a non-driving side cartridge cover member 123 provided at both ends of the process cartridge 100 in the longitudinal direction.

[0048] 9, a coupling member 125 for transmitting a driving force to the photosensitive drum 101 is provided on one end side of the photosensitive drum 101 in the longitudinal direction. The coupling member 125 is a main body side drum driving coupling as a drum driving output part of the image forming apparatus main body 2. 3. The photosensitive drum 101 has a drum flange 124 on the other longitudinal end side. A drive-side charge roller bearing 126a and a non-drive-side charge roller bearing 127a that support the charge roller 102 are supported by the drum frame 121 so that the charge roller 102 can contact the photosensitive drum 101 and rotate in the direction of arrow E in FIG. 3.

[0049] <Configuration of the development unit> As shown in FIGS. 3 and 8, the developing unit 150 is made up of a developing roller 103, a toner supplying roller 104 (supplying member), a developing blade 156, a developing frame (developing container), and the like.

[0050] The developing frame is made up of a first developing frame 151 and a second developing frame 152. The first developing frame 151 and the second developing frame 152 are joined by ultrasonic welding or the like. The developing frame has a toner storage portion 162 that stores toner to be supplied to the developing roller 103. The developing frame also rotatably supports the developing roller 103 and the toner supply roller 104 via a drive-side bearing 153 and a non-drive-side bearing 154, and holds a developing blade 156 that regulates the thickness of the toner layer on the circumferential surface of the developing roller 103. The toner storage portion 162 communicates with a developing chamber 174 via an opening 175. The toner supply roller 104 and the developing roller 103 are disposed in the developing chamber 174. When the cartridge is started to be used, the seal member of the opening 175 is removed, and toner is transported from the toner storage portion 162 to the developing chamber 174 by the rotation of the transport member 161.

[0051] The developing blade 156 is made by attaching an elastic member 156b, which is a sheet metal with a thickness of about 0.1 mm, to a supporting member 156a, which is a metal material with an L-shaped cross section, by welding, etc. The developing blade 156 is attached to the developing frame body at two points, one end side and the other end side in the longitudinal direction, with fixing screws 156c.

[0052] A development drive input gear 159 for transmitting a driving force to the development unit 150 is provided on one end side in the longitudinal direction of the development unit 150. The development drive input gear 159 is provided with a development input coupling 159a that receives driving force from the main body side development drive coupling 40 of the image forming apparatus main body 2, and the driving force of a drive motor (not shown) of the image forming apparatus main body 2 is input to the development unit 150.

[0053] The driving force input to the developing unit 150 is transmitted to the developing roller gear 157, causing the developing roller 103 to rotate in the direction of arrow C in Fig. 3, and is transmitted to the toner transport roller gear 158, causing the toner supply roller 104 to rotate in the direction of arrow D in Fig. 3. In addition, the driving force is transmitted to the stirring gear 160, causing the transport member 161 to rotate in the direction of arrow A in Fig. 3, stirring the toner in the toner storage section 162.

[0054] The conveying member 161 has a rotating shaft 161a that is parallel to the rotational axis direction of the developing roller 103, and flexible agitating sheets 161b and 161c. One end of the agitating sheets 161b and 161c is attached to the rotating shaft 161a, and the other end is a free end. When the rotating shaft 161a rotates, the agitating sheets 161b and 161c also rotate, and the toner is agitated by the agitating sheets 161b and 161c.

[0055] At one end of the developing unit 150 in the longitudinal direction, a developing device cover member 155 that supports and covers a developing device drive input gear 159 is provided.

[0056] <Assembling the drum unit and developing unit> The assembly of the drum unit 120 and the developing unit 150 will be described with reference to FIG. The drum unit 120 and the developing unit 150 are connected by a drive-side cartridge cover member 122 and a non-drive-side cartridge cover member 123, which are provided at both ends of the process cartridge 100 in the longitudinal direction. The drive-side cartridge cover member 122, which is provided at one end of the process cartridge 100 in the longitudinal direction, is provided with a developing unit support hole 122b for supporting the developing unit 150 in a swingable (movable) manner. Similarly, the non-drive-side cartridge cover member 123, which is provided at the other end of the process cartridge 100 in the longitudinal direction, is provided with a developing unit support hole 123b for supporting the developing unit 150 in a swingable manner.

[0057] Furthermore, the drive-side cartridge cover member 122 and the non-drive-side cartridge cover member 123 are provided with drum support holes 122a, 123a, respectively, for rotatably supporting the photosensitive drum 101. Here, at one end, the outer diameter portion of the cylindrical portion 155a of the developing cover member 155 is fitted into the developing unit support hole 122b of the drive-side cartridge cover member 122. At the other end, the outer diameter portion of the cylindrical portion (not shown) of the non-drive-side bearing 154 is fitted into the developing unit support hole 123b of the non-drive-side cartridge cover member 123. Furthermore, both longitudinal ends of the photosensitive drum 101 are fitted into the drum support hole 122a of the drive-side cartridge cover member 122 and the drum support hole 123a of the non-drive-side cartridge cover member 123. Then, the drive-side cartridge cover member 122 and the non-drive-side cartridge cover member 123 are fixed to the drum unit 120 with screws, adhesive, or the like (not shown).

[0058] As a result, the developing unit 150 is rotatably supported by the driving side cartridge cover member 122 and the non-driving side cartridge cover member 123 relative to the drum unit 120 (photosensitive drum 101), and the developing roller 103 can be positioned to act on the photosensitive drum 101 during image formation.

[0059] The drum unit 120 and the developing unit 150 are assembled through the above steps and integrally formed as the process cartridge 100, as shown in FIG.

[0060] The axis connecting the center of the developing unit support hole 122b of the drive-side cartridge cover member 122 and the center of the developing unit support hole 123b of the non-drive-side cartridge cover member 123 is referred to as the swing axis b. Here, the cylindrical portion 155a of the developing unit cover member 155 on one end side is coaxial with the developing input coupling 159a. In other words, the developing unit 150 is configured to receive driving force from the image forming apparatus main body 2 at this swing axis b. The developing unit 150 is also supported rotatably around the swing axis b.

[0061] <Configuration for detecting remaining toner amount> The configuration for detecting the remaining amount of toner (amount of developer) inside the developing unit 150 (inside the storage chamber) will be described with reference to Figures 11 to 15C. Figure 11, Figures 13A to 13C, and Figures 14A to 14C are cross-sectional views of the developing unit 150. All cross-sectional views in this embodiment, including these, are cross-sections relative to the posture in which the process cartridge 100 is mounted in the image forming apparatus main body 2, and each component in the figures is in the posture used for image formation. In these figures, the up-down direction of the figures coincides with the direction of gravity. These figures are cross-sectional views in a plane perpendicular to the conveying member rotation axis 171.

[0062] The developing unit 150 is provided with a remaining amount detection section 163 (detection section) including a first conductive member 164 and a second conductive member 165. The first conductive member 164 is provided on a wall surface 163a (first inner wall surface) of the frame of the developing unit 150, and the second conductive member 165 is provided on a wall surface 163b (second inner wall surface) adjacent to the wall surface 163a. ​​In this embodiment, the electrostatic capacitance between the first conductive member 164 and the second conductive member 165, which corresponds to the amount of developer, is detected.

[0063] Here, the detection member of the remaining amount detection unit 163 is made of a metal plate such as SUS that can detect capacitance, or a sheet member such as a conductive resin. In this embodiment, a conductive resin sheet is used, in which carbon black, a conductive material, is dispersed in resin. In the following explanation, a conductive member, which is one form of the detection member, is used.

[0064] <Configuration of remaining toner amount detection unit in toner storage unit> The configuration of the remaining amount detection unit 163 provided in the recess of the toner storage unit 162 will be described with reference to FIGS. 11, 12(a) and 12(b).

[0065] 11 is a cross-sectional view of the developing unit 150 at position PP in FIG. 8. As shown in FIG. 11, a recess recessed from the inside to the outside of the toner storage portion 162 is formed on the surface of the second developing frame 152 facing the toner storage portion 162 (corresponding to the inner wall surface of the developing unit 150). This recess, on which the remaining toner amount detection portion 163 is provided, is made up of two adjacent walls 163a and 163b. A first conductive member 164 is provided on the wall 163a, and a second conductive member 165 is provided on the wall 163b. Here, assuming that the rotation direction of the conveying member 161 is A, the wall 163a is the downstream wall in the rotation direction A of the conveying member 161, and the wall 163b is the upstream wall in the rotation direction A of the conveying member 161.

[0066] Next, the position of the recess formed by wall surfaces 163a and 163b in the toner storage portion 162 will be described. In FIG. 11, a region of the inner wall surface of the toner storage portion 162 on the opposite side of the opening 175 with respect to the rotation axis 171 of the conveying member is shown as a first region 176. In this embodiment, the opening 175 is located at the bottom of the toner storage portion 162 to connect the toner storage portion 162 to the developing chamber 174 below. Therefore, the first region 176 is located at the top of the inner wall surface of the toner storage portion 162. In this case, in the rotation direction A of the conveying member 161, the wall surfaces 163a and 163b forming the recess are located on the inner wall surface downstream of the opening 175 and upstream of the first region 176.

[0067] The angle formed by wall surface 163a on which first conductive member 164 is provided and the horizontal plane is the angle at which toner on first conductive member 164 falls under its own weight. The angle formed by wall surface 163b on which second conductive member 165 is provided and the horizontal plane is the angle at which toner on second conductive member 165 slides down under its own weight. In other words, when toner enters remaining amount detection unit 163, the toner is discharged from remaining amount detection unit 163 under its own weight, except for the amount carried out from the inside of remaining amount detection unit 163 by stirring sheets 161b and 161c.

[0068] In this embodiment, the normal N1 of wall surface 163a faces downward relative to the horizontal plane, so toner falls. On the other hand, although the normal N2 of wall surface 163b faces upward relative to the horizontal plane, the angle of wall surface 163b is an inclination angle equal to or greater than the angle of repose of the toner. By inclining wall surface 163b at an angle equal to or greater than the angle of repose of the toner, toner placed on wall surface 163b slides down wall surface 163b under its own weight. The angles of wall surface 163a and wall surface 163b relative to the horizontal plane are not limited to these, and may be any angle at which toner falls under its own weight.

[0069] An example of the configuration of the remaining amount detection unit 163 is shown with reference to the partially enlarged cross-sectional view of FIG. 1C. Here, the angle of repose is defined as r. This angle is the angle between the slope of the toner and the slope of the mountain when the toner is piled up to form a mountain, and refers to the maximum angle at which the toner remains stable without spontaneously collapsing. Therefore, if the angle of the slope of the toner with respect to the horizontal line H is equal to or less than the angle of repose r, the toner will not collapse. On the other hand, in this figure, the angle θ of the wall surface 163b with respect to the horizontal line H is equal to or greater than the angle of repose r, so the toner on the wall surface 163b slides down under its own weight. Since the angle of repose r of the toner used in this embodiment is approximately 40°, the angle θ of the wall surface 163b must be at least 40° or more, and is preferably 50° or more. The actual angle θ in this figure is 70.8°. Note that the flow rate may vary depending on the type of toner (for example, differences in surface properties due to the adhesion of external additives). The angle of repose of a toner varies depending on the toner type, and the more fluid the toner, the smaller the angle of repose. Therefore, the angle θ may be varied depending on the toner type.

[0070] 11, at least a portion of the recess in which the remaining amount detection unit 163 is provided is inside an imaginary circle T. The imaginary circle T is the circumference of a circle whose center is the conveying member rotation axis 171 and whose radius is R. Here, the radius R corresponds to the free length of the stirring sheets 161b and 161c (the length when the flexible sheets are assumed not to bend). The end of each of the stirring sheets 161b and 161c connected to the rotation shaft 161a is defined as one end, and the opposite end is defined as the other end. In this case, the imaginary circle T is a virtual rotational path described by the tips of the other ends of the stirring sheets 161b and 161c.

[0071] With this configuration, the tip sides of the stirring sheets 161b and 161c reliably contact at least a portion of the remaining amount detection unit 163. At this time, the flexible stirring sheets 161b and 161c bend and bring their tips into contact with the remaining amount detection unit 163 provided on the inner periphery of the frame. This is because the free length of the stirring sheets 161b and 161c in cross section is longer than the distance from one end to at least a portion of the remaining amount detection unit 163. Of course, as shown in FIG. 11, the entire recess may be located inside the imaginary circle T.

[0072] As the conveying member 161 rotates, the agitating sheets 161b and 161c pass through the remaining amount detection unit 163 while contacting the first conductive member 164 and the second conductive member 165. The length of the remaining amount detection unit 163 in the longitudinal direction (Y direction) of the developing unit 150 is longer than the length of the agitating sheets 161b and 161c in the Y direction. As the agitating sheets 161b and 161c pass through the remaining amount detection unit 163, they come into contact with the first conductive member 164 and the second conductive member 165, removing toner from the surfaces of the first conductive member 164 and the second conductive member 165. This allows toner to be removed from the remaining amount detection unit 163 in addition to the toner falling due to gravity.

[0073] 11, the first conductive member 164 includes not only a first portion 164a disposed on the wall surface 163a constituting the recess, but also a second portion 164b disposed on a wall surface 177 (third inner wall surface) connected above the wall surface 163a (i.e., on the opposite side of the wall surface 163b via the wall surface 163a). The wall surface 177 extends in a direction intersecting with the wall surface 163a and is provided on the frame body so that its surface faces upward. The wall surface 177 is provided above the wall surface 163a and the recess including the wall surface 163a in the direction of gravity, and is provided downstream of the wall surface 163a and upstream of the first region 176 in the direction of rotation A. To prevent toner from accumulating, the angle of the wall surface 177 with respect to the horizontal plane should be equal to or greater than the angle of repose of the toner.

[0074] Next, with reference to Figures 12(a) and 12(b), we will explain the two conductive members (first conductive member 164 and second conductive member 165) provided in the remaining amount detection unit 163. Figure 12(a) is a view of the second developing frame 152 as seen from the toner storage unit 162 side in Figure 8, and Figure 12(b) is a side view of Figure 12(a).

[0075] The first conductive member 164 and the second conductive member 165 are affixed to one longitudinal end of the second developing unit frame 152 without contacting each other. The portions where the first conductive member 164 and the second conductive member 165 are closest to each other are limited to a symmetrical range y from the longitudinal center. At one longitudinal end, a first conductive resin contact 167a and a second conductive resin contact 167b are formed on the second developing unit frame 152 by two-color molding. The first conductive resin contact 167a contacts the first conductive member 164, and the second conductive resin contact 167b contacts the second conductive member 165, thereby establishing electrical continuity between the inside and outside of the developing unit 150.

[0076] 8, the first conductive member 164 and the second conductive member 165 are connected to the image forming apparatus main body 2 via the first conductive resin contact 167a and the second conductive resin contact 167b. This makes it possible to apply a voltage to the first conductive member 164 and the second conductive member 165. With the above configuration, the first conductive member 164 and the second conductive member 165 act as electrodes, forming a capacitor inside the developing unit 150.

[0077] The range of the recess including wall surfaces 163a and 163b, first conductive member 164, and second conductive member 165 may be considered to be the remaining amount detection unit 163, or the remaining amount detection unit 163 may further include control unit 250 that calculates the remaining amount of toner based on the signals obtained by first conductive member 164 and second conductive member 165.

[0078] <Explanation of toner flow into and out of the remaining amount detector> 13A to 13C and 14A to 14C are cross-sectional views of the developing unit to explain how toner is transported by transport member 161. Figures 13A to 13C show how toner is transported by transport member 161 to remaining amount detection unit 163 when the remaining amount of toner is low.

[0079] In each figure, transported toner 166 is toner transported by agitation sheet 161b or 161c. In particular, Fig. 13B shows transported toner 166a passing through the remaining amount detection unit, Fig. 13C shows transported toner 166b on the agitation sheet after passing through the remaining amount detection unit, and Fig. 13C shows transported toner 166c that has fallen by gravity after passing through the remaining amount detection unit. Also, Fig. 13B shows transported toner 168 entering the remaining amount detection unit, and Fig. 14C shows transported toner 169b by agitation sheet 161b, transported toner 169c by agitation sheet 161c, and toner-free space 170.

[0080] 13A is a PP cross-sectional view of the developing unit 150 shown in FIG. 8 immediately before the stirring sheet 161b carries the toner into the remaining amount detection unit 163 as the conveying member 161 rotates in the direction A. Next, FIG. 13B is a cross-sectional view showing the toner distribution at the moment when the stirring sheet 161b passes through the remaining amount detection unit 163 and the conveyed toner 166a is detected.

[0081] In this way, the toner is lifted by the agitation sheet 161b, and the toner enters the remaining amount detection unit 163. Here, the leading edge of the agitation sheet 161b comes into contact with the inner walls of the wall surfaces 163a and 163b (first conductive member 164 and second conductive member 165), so the toner is pressed and pushed into the remaining amount detection unit 163 without spilling off the agitation sheet 161b.

[0082] 13C is a cross-sectional view showing the toner distribution after conveying member 161 has further rotated in direction A from the state in FIG. 13B and has just passed remaining amount detection unit 163. In this manner, some of conveyed toner 166b is lifted upward by stirring sheet 161b, and some of conveyed toner 166c falls under its own weight and is discharged from remaining amount detection unit 163.

[0083] 14A to 14C show how toner is transported by transport member 161 to remaining amount detection unit 163 when the remaining amount of toner is large. The phase of transport member 161 in FIGS. 14A to 14C is the same as that in FIGS. 13A to 13C, respectively.

[0084] 14A is a cross-sectional view showing the toner distribution just before stirring sheet 161b carries the toner into remaining amount detection unit 163 as transport member 161 rotates in direction A. Here, unlike FIG. 13A, since there is a large amount of remaining toner, the inside of remaining amount detection unit 163 is already filled with toner at this point.

[0085] Next, FIG. 14B is a cross-sectional view showing the toner distribution at the moment when the stirring sheet 161b pushes the toner into the remaining amount detecting portion 163. As shown in FIG.

[0086] 14C is a cross-sectional view showing the toner distribution immediately after agitation sheet 161b passes remaining amount detection unit 163. Toner is discharged from between first conductive member 164 and second conductive member 165, creating toner-free space 170. Therefore, when the remaining toner amount is high, toner remains in remaining amount detection unit 163 for a longer period of time than when the remaining toner amount is low.

[0087] <Method of detecting remaining toner> Because the dielectric constant of toner is higher than the dielectric constant of air, when toner gets between first conductive member 164 and second conductive member 165, the capacitance between first conductive member 164 and second conductive member 165 increases. Therefore, when toner transported by agitating sheets 161b and 161c passes between first conductive member 164 and second conductive member 165 as shown in FIG. 13B, the capacitance between first conductive member 164 and second conductive member 165 increases.

[0088] 13C, when agitation sheets 161b and 161c pass remaining amount detection unit 163 and the toner between first conductive member 164 and second conductive member 165 is carried out by agitation sheets 161b and 161c or falls due to its own weight, the capacitance between first conductive member 164 and second conductive member 165 decreases. Then, as described above, a voltage is applied to first conductive member 164 via first conductive resin contact 167a, and a voltage change based on the change in capacitance is detected via second conductive resin contact 167b connected to second conductive member 165.

[0089] As mentioned above, the time that toner remains in the remaining amount detection unit 163 varies depending on the remaining amount of toner. Therefore, the control unit 250 detects this change in time and refers to a table stored in memory that shows the correspondence between the change in time and the remaining amount of toner, thereby making it possible to identify the remaining amount of toner.

[0090] Here, there is a demand for further improvement in the accuracy of detecting remaining toner in this remaining toner amount detection system. To achieve this, the following describes in detail a configuration for stabilizing the detected toner amount when the remaining toner amount is low. Furthermore, as mentioned above, when the remaining toner amount is high, the remaining toner amount detection unit 163 tends to be filled with toner, making it difficult to detect fluctuations in capacitance. However, a configuration that enables remaining toner amount detection even in such cases will be described.

[0091] <Arrangement of remaining toner amount detector to stabilize detected toner amount> As mentioned above, since the remaining toner amount detection system is a system that notifies the user when toner is running low, it is necessary to improve the detection accuracy when toner is low. Toner remaining amount detection is a process that estimates the total remaining amount in development unit 150 by detecting the amount of toner carried into remaining amount detection unit 163 by agitation sheets 161b and 161c. Therefore, to improve detection accuracy, it is necessary that the amount of toner carried into remaining amount detection unit 163 by agitation sheets 161b and 161c per cycle is stable.

[0092] The solution to the above problem by this embodiment will be described with reference to Figures 1A and 1B. Figure 1A is a cross-sectional view in a direction perpendicular to conveying member rotation axis 171, showing the toner distribution when toner is pushed into remaining toner amount detection unit 163 when the remaining toner amount is low. Figure 1B is an enlarged view of the area around remaining toner amount detection unit 163 in Figure 1A.

[0093] As shown in FIG. 1A, in the configuration of this embodiment, when the remaining amount of toner is low, the toner 168 being conveyed to the remaining amount detection unit 163 is conveyed onto the agitation sheet 161b. The remaining amount detection unit 163 is located below the rotating shaft 161a of the conveying member 161, and therefore, when toner is conveyed to the remaining amount detection unit 163, the agitating sheet 161b assumes a posture that faces downward monotonically as it moves from the rotating shaft 161a side to the tip side.

[0094] FIG. 1B shows a specific arrangement of remaining amount detection unit 163. Conveying member rotation axis 171 indicates the rotation axis of rotating shaft unit 161a. Up-down position 171a is a horizontal extension line indicating the position of conveying member rotation axis 171 in the up-down direction (direction of gravity). The cross section shown in FIG. 1B shows intersection 172 where first virtual line 173a passing through wall surface 163a intersects with second virtual line 173b passing through wall surface 163b. This intersection 172 is a point included in the remaining amount detection unit virtual line, which is the intersection line of a plane including wall surface 163a and a plane including wall surface 163b.

[0095] In the configuration of this embodiment, the intersection point 172 is provided below the vertical position 171a which is at the same height as the conveying member rotation axis 171, and this is expressed as "the remaining amount detection unit 163 is located below the conveying member 161." Note that the remaining amount detection unit 163 may have a curve at the intersection line between the wall surface 163a and the wall surface 163b.

[0096] Here, let us assume that the remaining amount detection unit 163 is located above the conveying member 161 (i.e., the intersection 172 is located above the vertical position 171a). In this case, the agitating sheet 161b assumes a more horizontal position when toner is conveyed to the remaining amount detection unit 163. Therefore, the conveyed toner 168 is not biased toward the tip of the agitating sheet 161b, but spreads over the agitating sheet 161b, or may spill off the agitating sheet 161b toward the rotating shaft 161a. In this case, the amount of toner conveyed to the remaining amount detection unit 163 becomes unstable with each conveyance, resulting in a decrease in the accuracy of remaining amount detection. In contrast, in a configuration in which the remaining amount detection unit 163 is located below the conveying member 161 as in this embodiment, the conveyed toner 168 is biased toward the tip of the agitating sheet 161b, thereby making it possible to more stabilize the amount of toner conveyed to the remaining amount detection unit 163. This results in a more stable calculated remaining toner amount, improving the accuracy of remaining toner detection when the remaining toner amount is low.

[0097] This effect is achieved by the position of the remaining amount detection unit 163. Therefore, to achieve this effect, it is not necessary to provide multiple agitation sheets like the agitation sheets 161b and 161c of this embodiment, and a single agitation sheet will suffice.

[0098] In this embodiment, the remaining amount detection unit 163 is formed by two flat surfaces provided on the frame body, but the present invention can be applied as long as the remaining amount detection unit 163 can be evaluated as being below the conveying member 161. For example, the cross section may be a curve such as an arc. In that case, for example, an intersection 172 of the remaining amount detection unit virtual lines may be set at the midpoint between the end of the first conductive member 164 and the end of the second conductive member 165 in the cross section, and the intersection 172 may be configured to be below the vertical position 171a.

[0099] <Conveying member configuration that expands the range of remaining toner that can be detected> As mentioned above, the remaining toner amount detection system detects fluctuations in the capacitance of first conductive member 164 and second conductive member 165, which change as the amount of remaining toner decreases. Therefore, in order to expand the range of remaining toner amounts that can be detected, it is necessary to enable detection of remaining toner even when the remaining toner amount is large, when remaining toner amount detection unit 163 is likely to become filled with toner and it tends to be difficult to detect fluctuations in capacitance. To do this, it is necessary to be able to transport toner from remaining toner amount detection unit 163.

[0100] In this embodiment, the range in which the remaining amount can be detected is expanded by providing two stirring sheets on the conveying member 161. Details will be explained using FIG. 14C and FIGS. 15A to 15C. As described above, FIG. 1C is a cross-sectional view showing the toner distribution when toner is carried out from remaining amount detection unit 163 when the remaining amount of toner is large.

[0101] As described above, in the configuration of this embodiment, two agitation sheets 161b and 161c are provided on the rotation shaft portion 161a of the conveying member 161. Therefore, as shown in Fig. 14C, the toner in the developing unit 150 is divided into two types: conveyed toner 169b conveyed by agitation sheet 161b, and conveyed toner 169c conveyed by agitation sheet 161c.

[0102] At this time, as shown in Fig. 14C, immediately after agitation sheet 161b passes remaining amount detection unit 163, toner-free space 170 is formed downstream of agitation sheet 161b. This is a phenomenon that occurs when, in the phase of conveying member 161 in Fig. 14C, agitation sheet 161b acts as a roof to prevent conveyed toner 169b from falling around remaining amount detection unit 163, and agitation sheet 161c blocks the counterclockwise toner flow of conveyed toner 169b due to its own weight, preventing it from flowing into the area around remaining amount detection unit 163. By detecting toner-free space 170 formed in this way, remaining amount detection unit 163 can capture fluctuations in capacitance even when there is a large amount of remaining toner.

[0103] (Comparative Example) Here, we will explain how toner is transported to remaining amount detection unit 163 when using transport member 161 with a configuration different from that shown in Figures 14A to 14C. In this comparative example, we will explain the case where there is one stirring sheet. Figures 15A to 15C are cross-sectional views showing how toner is transported when there is one stirring sheet (only stirring sheet 161b), and each phase is the same as in Figures 14A to 14C.

[0104] In this comparative example, the absence of agitation sheet 161c causes conveyed toner 168b to flow counterclockwise in the figure. At this time, since toner flows into remaining amount detection unit 163 immediately after agitation sheet 161b passes remaining amount detection unit 163, no toner-free space 170 is created, and remaining amount detection unit 163 continues to be filled with toner throughout Figures 15A to 15C. In other words, since there is no change in capacitance, it becomes impossible to detect the remaining toner amount.

[0105] In contrast to this, in this embodiment, since there are two (multiple) stirring sheets, a toner-free space 170 is temporarily formed even when there is a large amount of remaining toner, and fluctuations in capacitance can be detected, thereby expanding the range of remaining toner that can be detected.

[0106] If there are multiple agitation sheets, the detectable range is expanded compared to when there is only one sheet, regardless of the installation angle, but it is more preferable to specify the installation angle. For example, when there are two agitation sheets as in this embodiment, it is preferable to install agitation sheets 161b and 161c in opposite directions relative to conveying member rotation axis 171, as shown in the cross-sectional view of Figure 14A. In other words, it is preferable to make the installation direction of agitation sheet 161b (the direction from one end connected to conveying member rotation axis 171 toward the other end, which is the tip) 180° different from the installation direction of agitation sheet 161c. This makes it possible to maximize the temporarily formed toner-free space 170.

[0107] The installation direction when there are two agitation sheets will be considered. In this embodiment, as shown in Fig. 3, agitation sheet 161b (first sheet) and agitation sheet 161c (second sheet) are respectively arranged in one area 162a and the other area 162b, which are divided by an imaginary line H that passes through conveying member rotation axis 171. Here, the imaginary line is horizontal, but the direction of the imaginary line is not limited to this.

[0108] Extending the above explanation to the case where there are N stirring sheets (N is an integer of 2 or more), it is preferable to make the installation directions of the stirring sheets differ by an angle obtained by dividing 360° into N. In other words, it is preferable that the installation directions of the first stirring sheet and the second stirring sheet adjacent to the first stirring sheet differ by (360 / N)°.

[0109] As described above, in this proposal, the remaining amount detection unit 163 is installed below the conveying member 161, so that the agitating sheets 161b and 161c tilt downward from the rotating shaft 161a toward the tip as they pass through the remaining amount detection unit 163. This prevents the toner from spilling from the agitating member toward the rotating shaft 161a of the conveying member 161, even when the remaining toner in the toner cartridge is decreasing and the amount of toner being conveyed is decreasing. Instead, the toner is distributed unevenly toward the tip of the agitating member. This allows the toner to be stably conveyed into the remaining amount detection unit 163. This stabilizes the amount of toner in the remaining amount detection unit 163, improving detection accuracy even when the remaining toner is low. Furthermore, by using multiple agitating sheets as shown in the embodiment, a toner-free space 170 can be formed around the remaining amount detection unit 163, even when the remaining toner is high, thereby improving detection accuracy.

[0110] In the above embodiment, the toner remaining amount detection was described using electrostatic capacitance. However, the above-described effects can also be achieved with optical toner remaining amount detection, in which a light-emitting element and a light-receiving element are provided through a detection window provided in the toner storage unit 162, and the remaining amount is detected based on the time at which the light-receiving element receives light. In other words, if the remaining amount detection unit 163 is installed below the transport member 161, even if the remaining toner is low, toner will not spill from the agitating sheets 161b and 161c when being transported to the remaining amount detection unit 163 provided in the developing frame.

[0111] The proposed configuration can be applied to a developing container or a developing frame used in an image forming apparatus, which contains a developer (toner) used to form an image on a recording medium 3. It can also be applied to a developing device (developing unit) that includes a developing container and develops an electrostatic latent image formed on a photosensitive drum 101. It can also be applied to an image forming apparatus that includes such a developing container or developing device.

[0112] The configuration of this proposal can also be applied to a process cartridge that forms a developer image on the photosensitive drum 101 and is detachable from the main body of the image forming apparatus 1, or a toner cartridge or developer cartridge that includes a developer container that can contain a developer. It can also be applied to an image forming apparatus 1 that includes a detachable main body for these cartridges and forms an image on a recording medium 3 using the developer in the developer container. When this proposal is applied to these cartridges, the positional relationships of the above-mentioned components (for example, the relationship with the direction of gravity and the vertical positional relationships) are based on the assumption that the cartridge is in the orientation when installed in the image forming apparatus.

[0113] [Configuration 1] A developing device used for image formation in an image forming apparatus, a container for containing a developer; a conveying member that is disposed inside the storage portion and has a shaft portion that is supported rotatably about a rotation axis line, and a flexible sheet that is connected to the shaft portion, and the sheet conveys the developer as the shaft portion rotates; a detection unit including a first conductive member and a second conductive member provided in the container unit, the detection unit detecting an electrostatic capacitance between the first conductive member and the second conductive member according to an amount of developer; Equipped with the frame of the accommodating portion has a recess in a cross section perpendicular to the rotation axis, the recess being formed by a first inner wall surface constituting the accommodating portion, the first inner wall surface being provided with the first conductive member, and a second inner wall surface extending in a direction intersecting the first inner wall surface and adjacent to the first inner wall surface, the second inner wall surface being provided with the second conductive member, the recess recessed from the inside to the outside of the accommodating portion; when the developing device is in a posture used for image formation in the image forming apparatus, the first inner wall surface faces downward, and the second inner wall surface faces upward and is configured to have an inclination angle equal to or greater than an angle of repose of the developer, In the cross section, an intersection point where a first virtual line passing through the first inner wall surface and a second virtual line passing through the second inner wall surface intersect is located below the rotation axis. A developing device characterized by: [Configuration 2] a developing chamber communicating with the container through an opening, to which the developer contained in the container is supplied through the opening; When a region of the inner wall surface of the storage portion on the opposite side of the opening with respect to the rotation axis is defined as a first region, the recess is located downstream of the opening and upstream of the first region in the rotation direction of the conveying member. 2. The developing device according to claim 1, [Configuration 3] Assuming that the shaft portion rotates in a state where the sheet is not bent, if the rotation locus drawn by the tip of the sheet on the side not connected to the shaft portion is taken as a virtual circle, the recessed portion is located inside the virtual circle. 3. The developing device according to configuration 1 or 2. [Configuration 4] The conveying member has at least two of the sheets. 3. The developing device according to configuration 1 or 2. [Configuration 5] When the number of sheets is N (N is an integer of 2 or more), the installation directions of adjacent sheets differ by (360 / N) degrees. 5. The developing device according to configuration 4. [Configuration 6] the frame body further has a third inner wall surface extending in a direction intersecting the first inner wall surface and adjacent to the first inner wall surface from a side opposite to the second inner wall surface, The first conductive member is provided so as to extend from the first inner wall surface to the third inner wall surface. 6. The developing device according to any one of configurations 1 to 5. [Configuration 7] a developer carrying member that carries the developer; and a supply member that supplies the developer in the container to the developer carrying member, and further includes a developing chamber that communicates with the container through an opening; When the developing device is in a position used for image formation in the image forming apparatus, the developing chamber is disposed below the accommodating portion. 7. The developing device according to any one of configurations 1 to 6. [Configuration 8] When the sheet is a first sheet, the conveying member has a second sheet connected to the shaft portion and having flexibility, In the cross section, the first sheet and the second sheet are respectively located in one area and the other area separated by an imaginary line passing through the rotation axis. 4. The developing device according to any one of configurations 1 to 3. [Explanation of symbols]

[0114] 1: image forming apparatus, 150: developing unit, 151: developing frame, 162: developer storage chamber, 161: transport member, 161a: rotating shaft portion, 161b: stirring sheet, 161c: stirring sheet, 162: toner storage portion, 163: remaining amount detection portion, 163a: wall surface, 163b: wall surface, 164: first conductive member, 165: second conductive member

Claims

1. A developing device used for image formation in an image forming apparatus, a container for containing a developer; a conveying member that is disposed inside the storage portion and has a shaft portion that is supported rotatably about a rotation axis line, and a flexible sheet that is connected to the shaft portion, and the sheet conveys the developer as the shaft portion rotates; a detecting unit including a first conductive member and a second conductive member provided in the container unit, the detecting unit detecting an electrostatic capacitance between the first conductive member and the second conductive member according to an amount of developer; Equipped with the frame of the accommodating portion has a recess in a cross section perpendicular to the rotation axis, the recess being formed by a first inner wall surface constituting the accommodating portion, the first inner wall surface being provided with the first conductive member, and a second inner wall surface extending in a direction intersecting the first inner wall surface and adjacent to the first inner wall surface, the second inner wall surface being provided with the second conductive member, the recess being recessed from the inside to the outside of the accommodating portion; when the developing device is in a position used for image formation in the image forming apparatus, the first inner wall surface faces downward, and the second inner wall surface faces upward and is configured to have an inclination angle equal to or greater than an angle of repose of the developer, In the cross section, an intersection point where a first virtual line passing through the first inner wall surface and a second virtual line passing through the second inner wall surface intersect is located below the rotation axis. A developing device characterized by:

2. a developing chamber communicating with the container through an opening, to which the developer contained in the container is supplied through the opening; When a region of the inner wall surface of the storage portion that is on the opposite side of the opening with respect to the rotation axis is defined as a first region, the recess is located downstream of the opening and upstream of the first region in the rotation direction of the conveying member.

2. The developing device according to claim 1.

3. Assuming that the shaft portion rotates in a state where the sheet is not bent, if the rotation locus drawn by the tip of the sheet on the side not connected to the shaft portion is taken as a virtual circle, the recessed portion is located inside the virtual circle.

3. The developing device according to claim 1, wherein the developing device is a developing unit.

4. The conveying member has at least two of the sheets.

2. The developing device according to claim 1.

5. When the number of sheets is N (N is an integer of 2 or more), the installation directions of adjacent sheets differ by (360 / N) degrees.

5. The developing device according to claim 4.

6. the frame body further has a third inner wall surface extending in a direction intersecting the first inner wall surface and adjacent to the first inner wall surface from a side opposite to the second inner wall surface, The first conductive member is provided so as to extend from the first inner wall surface to the third inner wall surface.

3. The developing device according to claim 1, wherein the developing device is a developing unit.

7. a developer carrying member that carries the developer; and a supply member that supplies the developer in the container to the developer carrying member, and further includes a developing chamber that communicates with the container through an opening; When the developing device is in a position used for image formation in the image forming apparatus, the developing chamber is disposed below the accommodating portion.

3. The developing device according to claim 1, wherein the developing device is a developing unit.

8. When the sheet is a first sheet, the conveying member has a second sheet connected to the shaft portion and having flexibility, In the cross section, the first sheet and the second sheet are respectively located in one area and the other area separated by an imaginary line passing through the rotation axis.

2. The developing device according to claim 1.

Images