Developing apparatus and image forming apparatus

Abstract

In an image forming apparatus in which a rotating body is provided inside the developer container and a restricting member is provided below the rotating body to restrict the fall of the developer, the developer sometimes aggregated due to the restricting member, and the developer was not properly supplied to the required location. [Solution] The drum unit 70 having a toner receiving port 81 includes a developing chamber 79 for storing toner 45 supplied from the toner receiving port 81, a toner transport member 77 extending in the longitudinal direction of the developing chamber 79 and transporting the toner 45 in the developing chamber 79 from the toner receiving port 81 toward at least one end, and one side wall 85 having the inner surface of the developing chamber 79 extending below the toner transport member 77, wherein the inner surface has a first inner surface (85a, 85d) on the end side in the longitudinal direction and a second inner surface (85a, 85c, 85b) on the toner receiving port 81 side, and the first inner surface is recessed in a direction that widens the internal space of the developing chamber 79 compared to the second inner surface.

Description

Technical Field

[0005] , ,

[0001] The present invention relates to an image forming apparatus and an image forming unit, and particularly to the structure of a toner storage portion of the image forming unit.

Background Art

[0002] Conventionally, an image forming unit and an image forming apparatus are known in which a rotating body is provided inside a developer container, and a regulating member for regulating the fall of the developer is provided below the rotating body (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, there has been a problem that the developer may aggregate due to the regulating member and the developer may not be appropriately supplied to the required locations. The object of the present invention is to provide an image forming unit and an image forming apparatus in which the developer is appropriately supplied.

Means for Solving the Problems

[0005] The developing device according to the present invention is a developing device provided in an image forming apparatus and having a supply port for receiving the supply of a developer, The device comprises a developer storage section for storing the developer supplied from the supply port, a transport member extending in the longitudinal direction of the developer storage section and transporting the developer inside the developer storage section from the supply port toward at least one end, and a regulating section extending below the transport member and having the inner surface of the developer storage section, wherein the inner surface of the regulating member has a first inner surface on the end side in the longitudinal direction and a second inner surface on the supply port side, and the first inner surface is recessed in a direction that widens the internal space of the developer storage section compared to the second inner surface. [Effects of the Invention]

[0006] According to the present invention, the developer being transported towards both ends within the developer storage section can fall without agglomerating at both ends, thus enabling proper supply of the developer. [Brief explanation of the drawing]

[0007] [Figure 1] This is a diagram showing the main components of an image forming apparatus of Embodiment 1 employing a drum unit based on the present invention. [Figure 2] This is a diagram showing the main components of the internal structure of the image forming unit. [Figure 3] This is a perspective view of the drum unit from an oblique angle above, after the toner cartridge has been removed from the image forming unit. [Figure 4] Figure 2 shows a cross-sectional view AA of the drum unit. [Figure 5] Figure 4 is a cross-sectional view of BB. [Figure 6] Figure 4 is a cross-sectional view of CC. [Figure 7] This is a cross-sectional view of the main part of the drum unit of Embodiment 2 according to the present invention, at the same position as Figure 4 (cross-sectional view AA in Figure 2) in Embodiment 1. [Figure 8] Figure 7 is a cross-sectional view of KK. [Figure 9] Figure 7 is a cross-sectional view of LL. [Modes for carrying out the invention]

[0008] Embodiment 1. Figure 1 is a diagram showing the main components of an image forming apparatus 1 of Embodiment 1, which employs a drum unit 70 based on the present invention.

[0009] As shown in the figure, the image forming apparatus 1 is configured as an electrophotographic printer, and the paper feed tray 12 has recording paper 40 as a recording medium stacked inside and is detachably attached to the bottom of the main body of the image forming apparatus 1. The pickup roller 15, which serves as a feeding member, together with the paper feed roller 16 and the separation roller 17 which are arranged in contact with each other, constitutes the paper feeding section 35. The pickup roller 15 and the paper feed roller 16 are rotationally driven by a drive motor (not shown), and the separation roller 17 generates torque in the counter-rotation direction by a torque generating means (not shown).

[0010] Therefore, the pickup roller 15 feeds out the topmost recording paper 40 that it is in contact with from inside the paper tray 12, and the paper feed roller 16 and separation roller 17 separate the recording paper 40 one by one and feed them sequentially into the transport path, even if, for example, multiple sheets of recording paper 40 are pulled out at the same time.

[0011] In the transport path downstream of the paper feed unit 35 in the transport direction of the recording paper 40, a transport roller pair 18 and a registration roller pair 19 are arranged in that order. The transport roller pair 18 transports the recording paper 40 to the registration roller pair 19, and the registration roller pair 19 corrects the skew of the recording paper 40 by starting paper transport after the recording paper 40 comes into contact with the paper based on the paper detection timing of the paper sensor 36 that detects the passage of the recording paper 40, and then feeds it to the image forming unit.

[0012] The image forming unit includes an image forming unit 11 having an image drum 71 as an image carrier on which toner development is formed, which rotates in the direction of the arrow, and a transfer roller 31 which is positioned opposite the image drum 71 and presses against it to transfer the toner development to the recording paper 40. The image forming unit 11 is configured to be detachable from the main body of the image forming apparatus 1.

[0013] As the recording paper 40 fed into the image forming unit passes through the contact area between the image drum 71 and the transfer roller 31, the toner development formed on the circumferential surface of the image drum 71 is transferred onto the paper surface by the transfer roller 31 to which a predetermined transfer voltage is applied. The image forming unit 11 starts the process of forming the toner development on the circumferential surface of the image drum 71 based on the paper detection timing of the paper sensor 37, which detects the recording paper 40 after it has passed through the registration roller pair 19.

[0014] The fuser 32 has a heating roller 33 that rotates in the direction of the arrow and a pressure roller 34 that is positioned to be pressed against it. The nip portion pressed by these rollers is heated and pressurized as the recording paper 40, to which the toner developer has been transferred, passes, fixing the toner developer to the recording paper 40. The printed recording paper 40, which has been fed out of the fuser 32 along the transport path, is sent to the discharge roller pair 21 via the transport roller pair 20, and discharged to the stacker section 22 by the discharge roller pair 21. The image forming unit 11, which includes the drum unit 70, will be described in detail later.

[0015] In Figure 1, the X, Y, and Z directions represent the transport direction of the recording paper 40 as it passes through the contact area between the image drum 71 and the transfer roller (X direction), the rotation axis direction of the image drum 71 (Y direction), and the direction perpendicular to both of these axes (Z direction). In other figures described later, when the X, Y, and Z directions are shown, these directions represent a common direction. That is, the XYZ directions in each figure indicate the arrangement direction of the depicted parts when they constitute the image forming apparatus 1 shown in Figure 1. Here, the arrangement is assumed to be approximately vertical (Z direction).

[0016] FIG. 2 is a main component configuration diagram showing the main component configuration inside the image forming unit 11, FIG. 3 is a perspective view of the drum unit 70 when the toner cartridge 50 is removed from the image forming unit 11, viewed obliquely from above, FIG. 4 is a cross-sectional view taken along the line A-A in FIG. 2 showing the inside of the drum unit 70, FIG. 5 is a cross-sectional view taken along the line B-B in FIG. 4, and FIG. 6 is a cross-sectional view taken along the line C-C in FIG. 4.

[0017] As shown in FIG. 2, the image forming unit 11 is composed of a drum unit 70 as a developing device and a toner cartridge 50. The toner cartridge 50 located above is configured to be detachable by moving in the vertical direction with respect to the drum unit 70. That is, when the toner 45 as a developer accommodated in the toner cartridge 50 moves to the drum unit 70 and becomes empty as described later, it is replaced with a new toner cartridge 50.

[0018] The drum unit 70 includes an image drum 71, a developing roller 72 as a developer carrier, a layer forming blade 73, a charging roller 74, a cleaning blade 75, a supply roller 76 as a supply member, a toner transport member 77, a toner remaining amount detection member 78, a developing chamber 79, and a drum unit main body frame 80.

[0019] The charging roller 74 uniformly charges the surface of the image drum 71, and the developing roller 72 attaches toner 45 to the electrostatic latent image formed on the surface of the image drum 71 by an exposure device (not shown) to form toner development. The layer forming blade 73 pressed against the developing roller 72 thins the toner 45 supplied from the supply roller 76 on the developing roller 72. The supply roller 76 supplies the toner 45 in the developing chamber 79 to the developing roller 72, and the cleaning blade 75 is pressed against the surface of the image drum 71 to scrape off the toner 45 remaining on the image drum 71 after transfer.

[0020] As shown in Figure 4, the toner transport member 77, which serves as a transport member, comprises a shaft portion 77c that extends in the longitudinal direction (arrow Y direction) of the drum unit 70 within the developing chamber 79, which serves as a developer storage section, and a second helical member, a helical blade portion 77a, formed on the shaft portion 77c from near its center to near one end, and a first helical member, a helical blade portion 77b, formed near the other end. Here, the helical blade portions 77a and 77b have opposite helical directions.

[0021] The toner level detection member 78, which acts as a developer level detection member, extends in the longitudinal direction (arrow Y direction) of the drum unit 70 within the developing chamber 79. As shown in Figure 5, both ends of the shaft 78a are crank-bent, with one end protruding outward through the developing chamber, and a reflector plate 78c (Figure 4) is attached to the tip of the protruding part. This reflector plate 78c is used to detect the time the toner level detection member 78 is in a specific phase that changes in accordance with the toner level in the developing chamber 79.

[0022] As shown in Figure 3, the drum unit 70 has a toner receiving port 81 formed in the longitudinal center of the mounting section on which the toner cartridge 50 is placed, which serves as a supply port for receiving toner 45 supplied from the toner cartridge 50 into the developing chamber 79, and a sealing member 82 made of an elastic material is arranged around the toner receiving port 81. In the future, the front-to-back, left-to-right, and up-and-down directions of the drum unit 70 may be specified when viewed from the direction of arrow H (arrow X) shown in the same figure.

[0023] Of the inner wall surfaces forming the developing chamber 79 of the drum unit main frame 80 (Figure 2), one side wall 85, which extends longitudinally (arrow Y direction) adjacent to the supply roller 76 and serves as a restricting portion, has a different shape in the central region Wa and the left and right end regions Wb, as shown in Figure 4. The central region Wa is a region that extends from the center of the developing chamber 79 in the longitudinal direction to near both the left and right ends, with a central distribution, while the left and right end regions Wb are regions on either side of the central region Wa that extend to the left and right ends of the developing chamber 79, respectively.

[0024] One side wall 85, in the central region Wa, consists of a vertical tangential wall portion 85b that is tangentially continuous from the bottom surface formed in a circular arc shape along the circumferential surface of the supply roller 76, as shown in Figure 5, which is a cross-sectional view of BB in Figure 4; a circular arc-shaped wall portion 85c that is formed continuously therefrom and follows the rotational trajectory of the toner remaining amount detection member 78; and a vertical wall portion 85a that is continuous therewith. Here, the vertical tangential wall portion 85b, the circular arc-shaped wall portion 85c, and the vertical wall portion 85a correspond to the second inner surface portion.

[0025] On the other hand, in the end region Wb, one side wall 85 consists of an inclined wall surface portion 85d that is tangentially continuous from the bottom surface formed in a circular arc shape along the circumferential surface of the supply roller 76, as shown in Figure 6, which is a cross-sectional view of CC in Figure 4, and a vertical wall surface 85a that is continuous therewith. Here, the shape of one side wall 85 in the right end region Wb has been described, but the shape of one side wall 85 in the left end region Wb is exactly the same. Here, the inclined wall surface portion 85d and the vertical wall surface 85a correspond to the first inner surface portion.

[0026] Here, the spiral blades 77a and 77b of the toner transport member 77 are formed such that their respective outer ends are contained within the central region Wa, as shown in Figure 4. This is to prevent strong transport forces from being generated in the left and right end regions Wb where the first inner surface is formed, in the direction of each end relative to the toner 45, as will be described later.

[0027] As shown in Figure 2, when the toner cartridge 50 is mounted on the drum unit 70, it has a toner supply port 51 that faces a toner receiving port 81 formed in the drum unit 70. The toner supply port 51 is joined to the toner receiving port 81 via a sealing member 82 (Figure 3), so that the inside of the toner cartridge 50 and the developing chamber 79 are spatially connected in a sealed state, and the toner 45 inside the toner cartridge 50 can be supplied to the developing chamber 79.

[0028] In the above configuration, the operation inside the developing chamber 79 while the image forming unit 11 is in operation will now be described.

[0029] During the operation of the image forming unit 11, toner is supplied from inside the toner cartridge 50 to the developing chamber 79 via the toner supply port 51 and the toner receiving port 81 formed in the drum unit 70. At this time, the joint between the toner supply port 51 and the drum unit 70 is sealed by the sealing member 82.

[0030] The toner 45 stored in the developing chamber 79 is transported by a toner transport member 77 that rotates in the direction of arrow G (Figure 5) towards both ends along its axial direction, i.e., in the directions of arrows D and E shown in Figure 4. At this time, transport in the direction of arrow D is performed by the spiral blade section 77a, and transport in the direction of arrow E is performed by the spiral blade section 77b. As a result, the toner 45 supplied to the developing chamber 79 is deposited almost uniformly within the developing chamber 79.

[0031] The toner level detection member 78 has a detection arm portion 78b (Figure 5) that is crank-bent in accordance with the rotation of the shaft 78a, which rotates and moves within the developing chamber 79 in areas where toner is present or areas where toner is absent. At this time, the rotation is configured to change according to the amount of toner remaining in the developing chamber 79, and toner level information is obtained by detecting this change in rotation.

[0032] For example, the system is configured so that when the amount of toner remaining in the developing chamber 79 falls below a certain amount, the detection time of the reflector plate 78c changes, and by detecting this change, it is determined that the amount of toner 45 in the developing chamber 79 is decreasing.

[0033] As described above, the toner 45 supplied into the developing chamber 79 is transported by the toner transport member 77 towards both the left and right ends, and is therefore continuously supplied to both ends of the developing chamber 79. Consequently, the toner 45 supplied to these ends reaches, for example, the inclined wall surface 85d of one of the side walls 85 at the right end of the developing chamber 79 shown in Figure 6. The same applies to the left end of the developing chamber 79.

[0034] As described above, in the central region Wa in the longitudinal direction of the developing chamber 79 shown in Figure 4, one side wall 85 has a shape in which a vertical tangential wall portion 85b, which extends vertically upward tangentially from a bottom surface formed in a circular arc shape along the circumferential surface of the supply roller 76, and a further outer vertical wall portion 85a are continuously connected by a circular arc-shaped wall portion 85c that is formed substantially coaxially with the shaft 78a of the toner remaining amount detection member 78, as shown in the cross-sectional view in Figure 5.

[0035] On the other hand, in the end region Wb, as shown in Figure 6, one side wall 85 has an inclined wall surface portion 85d that extends tangentially diagonally upward (outward) from the bottom surface formed in a circular arc shape along the circumferential surface of the supply roller 76, and this inclined wall surface portion 85d is directly and continuously connected to the outer vertical wall surface 85a.

[0036] The virtual wall section 100, depicted by a dotted line in Figure 5, is a partial addition of one side wall 85 in the end region Wb for comparison. As shown in the figure, the first inner surface section (dotted line section), consisting of the inclined wall surface section 85d and the vertical wall surface 85a, is recessed in a direction that expands the internal space of the developing chamber 79 relative to the second inner surface section, consisting of the vertical tangent wall surface section 85b, the arc-shaped wall surface section 85c, and the vertical wall surface 85a. The amount of recess can be, for example, the difference in area resulting from the comparison between the first inner surface section and the second inner surface section in the cross-section shown in Figure 5.

[0037] Here, we consider the case where, in all regions along the longitudinal direction of the developing chamber 79 shown in Figure 4, one side wall 85 has a continuous shape consisting of a vertical tangential wall surface 85b, an arc-shaped wall surface 85c, and a vertical wall surface 85a, as shown in the cross-section of the central region Wa (cross-section shown in Figure 5).

[0038] In this case, the toner 45, which is transported and compressed to both the left and right ends of the developing chamber 79 by the toner transport member 77, becomes denser at those ends. As a result, the compacted toner 45 adheres to, for example, the arc-shaped wall surface 85c surrounding the toner remaining amount detection member 78, hindering the rotation of the detection arm 78b of the toner remaining amount detection member 78, for example, rotation due to gravity. This made it possible that the toner remaining amount detection member 78 could not correctly detect the remaining amount of toner 45.

[0039] On the other hand, in the drum unit 70 of this embodiment, the left and right end regions Wb, which correspond to the left and right ends of the developing chamber 79, are such that, as shown in the cross-sectional view of Figure 6, one side wall 85 is formed by a continuous inclined wall surface 85d and a vertical wall surface 85a. Therefore, the supply roller 76 that rotates in the direction of arrow F and one side wall 85 are in the closest proximity between the circumferential surface of the supply roller 76 and the inclined wall surface 85d of one side wall 85.

[0040] Therefore, near both ends of the developing chamber 79 of the drum unit 70, the space formed by one side wall 85 and the supply roller 76 below the toner remaining amount detection member 78 expands, thereby suppressing an increase in the density of toner 45 that is transported and pushed into both the left and right ends of the developing chamber 79. Furthermore, since the left and right spiral blades 77a and 77b of the toner transport member 77 do not extend beyond the central region Wa to the left and right, the toner transport force at both the left and right ends of the developing chamber 79 is weakened, further suppressing an increase in the density of toner 45.

[0041] Furthermore, the circumferential surface of the supply roller 76 and the inclined wall portion 85d are closer together at a lower point than when they are with the vertical tangential wall portion 85b in the central region Wa, i.e., upstream of the contact point between the developing roller 72 and the supply roller 76 in the rotational direction of the supply roller 76 (arrow F direction). As a result, the amount of toner 45 moving along the circumferential surface of the supply roller 76 in the direction of arrow F increases. This makes the charging of the toner 45 by the supply roller 76 more stable.

[0042] As described above, the drum unit 70 according to this embodiment can suppress the increase in density of toner 45 transported to the left and right ends of the developing chamber 79. Therefore, the rotation of the toner remaining amount detection member 78 is not obstructed by the attached or solidified toner 45, and thus the remaining amount of toner 45 can always be detected correctly. Furthermore, since the charging of the toner 45 is stabilized throughout the entire longitudinal direction of the drum unit 70, it is possible to suppress printing defects.

[0043] Embodiment 2. Figure 7 is a cross-sectional view of the main part of the drum unit 170 of Embodiment 2 according to the present invention, at the same position as Figure 4 (cross-sectional view AA in Figure 2) in Embodiment 1, Figure 8 is a cross-sectional view KK in Figure 7, and Figure 9 is a cross-sectional view LL in Figure 7.

[0044] The main difference between the drum unit 170 of this embodiment shown in these figures and the drum unit 70 of Embodiment 1 is that the toner transport member 77 is placed in the position of the toner remaining amount detection member 78 (see Figure 5) described in Embodiment 1, and the toner remaining amount detection member 78 described in Embodiment 1 is omitted.

[0045] Therefore, parts of the drum unit 170 of this embodiment 2 that are common with the drum unit 70 of embodiment 1 described above will be denoted by the same reference numerals, or the drawings will be omitted and the explanation will be omitted, with the differences being explained in detail. Note that the main components of the image forming apparatus of this embodiment are common with the main components of the image forming apparatus 1 of embodiment 1 shown in Figure 1, except for the drum unit, so please refer to Figure 1 as needed.

[0046] In the drum unit 170 of this second embodiment, the toner 45 supplied into the developing chamber 79 is continuously transported in the direction of both the left and right ends along its axial direction by the toner transport member 77 which rotates in the direction of arrow N (Figure 8). At this time, transport to the left is performed by the spiral blade section 77a, and transport to the right is performed by the spiral blade section 77b.

[0047] As a result, the toner 45 supplied to both ends reaches, for example, the inclined wall surface 85d of one of the side walls 85 in the cross-sectional view of Figure 9, which shows a cross-section near the right end of the developing chamber 79. The same applies to the left end of the developing chamber 79.

[0048] Furthermore, in the developing chamber 79 of the drum unit 170 of this embodiment, similar to the drum unit 70 of Embodiment 1, the first inner surface portion consisting of the inclined wall surface portion 85d and the vertical wall surface 85a in the end region Wb is recessed in a direction that widens the internal space of the developing chamber 79 relative to the second inner surface portion consisting of the vertical tangential wall surface portion 85b, the arc-shaped wall surface portion 85c, and the vertical wall surface 85a in the central region Wa.

[0049] Here, we consider the case where, in all regions along the longitudinal direction of the developing chamber 79 shown in Figure 7, one side wall 85 has a continuous shape consisting of a vertical tangential wall surface 85b, an arc-shaped wall surface 85c, and a vertical wall surface 85a, as shown in the cross-section of the central region Wa (cross-section shown in Figure 8).

[0050] In this case, the toner 45, which is transported and compressed to both the left and right ends of the developing chamber 79 by the toner transport member 77, becomes denser at those ends. As a result, the compacted toner 45 may adhere to, for example, the arc-shaped wall surface 85c surrounding the toner transport member 77, potentially hindering smooth toner transport by the toner transport member 77.

[0051] On the other hand, in the drum unit 170 of this embodiment, the left and right end regions Wb, which correspond to the left and right ends of the developing chamber 79, are such that, as shown in the cross-sectional view of Figure 9, one side wall 85 extending below the toner transport member 77 is formed by a continuous inclined wall surface 85d and a vertical wall surface 85a. Therefore, the supply roller 76 rotating in the direction of arrow F and one side wall 85 are in the closest proximity between the circumferential surface of the supply roller 76 and the inclined wall surface 85d of one side wall 85.

[0052] Therefore, near both ends of the developing chamber 79 of the drum unit 170, the space formed by one side wall 85 and the supply roller 76 below the toner transport member 77 expands, thereby suppressing an increase in the density of toner 45 that is transported and pushed into both the left and right ends of the developing chamber 79. Furthermore, since the left and right spiral blades 77a and 77b of the toner transport member 77 do not extend beyond the central region Wa to the left and right, the toner transport force at both the left and right ends of the developing chamber 79 is weakened, further suppressing an increase in the density of toner 45.

[0053] Furthermore, in the central region Wa, as shown in Figure 8, the expansion is restricted in a portion of the space above and below the toner transport member 77 by an arc-shaped wall portion 85c formed substantially coaxially with the shaft portion 77c (Figure 7) of the toner transport member 77, thereby increasing the transport force to both ends of the toner 45.

[0054] Furthermore, the circumferential surface of the supply roller 76 and the inclined wall portion 85d are closer together at a lower point than when they are with the vertical tangential wall portion 85b in the central region Wa, i.e., upstream of the contact point between the developing roller 72 and the supply roller 76 in the rotational direction of the supply roller 76 (arrow F direction). As a result, the amount of toner 45 moving along the circumferential surface of the supply roller 76 in the direction of arrow F increases. This stabilizes the charging of the toner 45 by the supply roller 76.

[0055] As described above, the drum unit 170 according to this embodiment prevents an increase in the density of toner 45 transported to the left and right ends of the developing chamber 79, thereby suppressing the adhesion and solidification of toner 45 around the toner transport member 77. This allows for smooth toner transport by the toner transport member 77 and enables a stable supply of toner to the supply roller 76.

[0056] Furthermore, since the charging of the toner 45 is stabilized throughout the entire longitudinal direction of the drum unit 170, it is possible to suppress printing defects.

[0057] Furthermore, although terms such as "up," "down," "left," "right," "front," and "back" were used in the above-mentioned claims and descriptions of embodiments, these are for convenience only and do not limit the absolute positional relationships in the state in which the developing apparatus is placed. [Industrial applicability]

[0058] In the embodiments described above, an example was shown in which the present invention is used in an image forming apparatus 1 as a monochrome printer. However, the present invention is not limited to this and can also be used in image processing devices such as copiers, facsimile machines, and MFPs. Furthermore, although a monochrome printer has been described, a color printer may also be used. [Explanation of symbols]

[0059] 1 Image forming apparatus, 11 Image forming unit, 15 Pickup roller, 16 Paper feed roller, 17 Separation roller, 18 Transport roller pair, 19 Resist roller pair, 20 Transport roller pair, 21 Discharge roller pair, 31 Transfer roller, 32 Fuser, 33 Heating roller, 34 Pressure roller, 35 Paper feeding section, 36 Paper sensor, 37 Paper sensor, 40 Recording paper, 45 Toner, 50 Toner cartridge, 51 Toner supply port, 70 Drum unit, 71 Image drum, 72 Developing roller, 73 Layer forming blade, 74 Charging roller, 75 Cleaning blade, 76 Supply roller, 77 Toner transport member, 77a Helical blade section, 77b Helical blade section, 77c Shaft section, 78 Toner remaining amount detection member, 78a 78b Axis, 78c Detection arm, 78c Reflector, 79 Developing chamber, 80 Drum unit main frame, 81 Toner inlet, 82 Sealing member, 85 One side wall, 85a Vertical wall surface, 85b Vertical tangent wall surface, 85c Arc-shaped wall surface, 85d Inclined wall surface, 100 Virtual wall surface, 170 Drum unit.

Claims

1. In a developing apparatus provided in an image forming apparatus and having a supply port for receiving a supply of developer, A developer storage unit for storing the developer supplied from the supply port, A transport member extending in the longitudinal direction of the developer storage section, transporting the developer inside the developer storage section from the supply port toward at least one end, A restricting portion having the inner surface of the developer storage portion that extends downward from the transport member and Equipped with, The inner surface of the regulating member has a first inner surface on the one end side in the longitudinal direction and a second inner surface on the supply port side. A developing apparatus characterized in that the first inner surface is recessed in a direction that widens the internal space of the developer storage section compared to the second inner surface.

2. A developer carrier that develops the electrostatic latent image of an image carrier using a developer, When the developing device is mounted on the image forming apparatus, a supply member extends in the longitudinal direction below the transport member and supplies the developer to the developer carrier. Equipped with, The developing apparatus according to claim 1, characterized in that the developer falling along the first inner surface falls more towards the upstream side in the rotational direction of the supply member with respect to the contact portion between the supply member and the developer carrier than the developer falling along the second inner surface.

3. The aforementioned transport member is A first helical member generates a transport action that moves the developer from the supply port toward one end of the transport member, A second spiral member generates a transport action that moves the developer from the supply port toward the other end of the transport member. Equipped with, The developing apparatus according to claim 1 or 2, characterized in that the first helical member and the second helical member are arranged in the longitudinal direction within the region where the second inner surface portion is formed.

4. The developing apparatus according to claim 2, characterized in that, when the developing apparatus is mounted on the image forming apparatus, a developer remaining amount detection member is provided above the supply member, extending in the longitudinal direction to detect the remaining amount of the developer.

5. An image forming apparatus characterized by comprising the developing apparatus described in claim 1 or 2.

Images