JP5617224B2 - Developing device and image forming apparatus - Google Patents

Description

  The present invention relates to a developing device and an image forming apparatus.

  In an image forming apparatus such as a copying machine or a printer to which an electrophotographic system is applied, a toner image is formed on a photosensitive drum by a developing device by using an electrostatic latent image formed on the photosensitive drum. The transferred toner image is transferred onto a recording medium, and the transferred toner image is fixed on the recording medium to form a printed image. As the developer, for example, a two-component developer composed of toner and carrier is used.

  Here, as an image forming apparatus, there is an image forming apparatus in which a developer is stored in a developer storage chamber before use of the developing device (see, for example, Patent Document 1). In the image forming apparatus of Patent Document 1, a developer storage chamber capable of storing a starter developer is provided above a developer storage chamber in a development housing. This section defines a substantially rectangular space extending along the axial direction of the developing roll, is arranged so as to partially overlap the vertical direction area of the developing roll, and has a developer inlet at its lower end.

JP 2006-276534 A

  An object of the present invention is to suppress fluctuations in the amount of developer supplied to an image holding member depending on the supply state of the developer with respect to the developer holding member.

According to the first aspect of the present invention, an initial developer storage chamber in which a developer containing toner and a carrier is stored in a partition, a developer holding member that rotates while holding the developer on the surface, and the initial developer storage A developer transport chamber in which the developer contained in the chamber flows and transports the developer to the developer holding member; and a part of the partition wall of the initial developer storage chamber, the initial developer storage chamber And a first developer supply for supplying the developer toward the developer holding member at least partly opened vertically above the developer holding member and mouth, and a partition wall having a corresponding initial developer accommodating chamber and the developer second developer supply port for supplying the developer to the developer transport chamber disposed between the transfer chamber, the first 1 of the developer supply port and the second developer supply port A first sealing member and a second sealing member, a thin layer forming member disposed to form a predetermined gap relative to said developer holding member for sealing respectively, the thin Displacement that occurs when the developer is supplied from the first developer supply port and that is disposed in contact with the layer forming member, in a direction in which the thin layer forming member is separated from the developer holding member. A developing device having a displacement suppressing member for suppressing.

A second aspect of the present invention is the developing device according to the first aspect of the present invention, which is formed by a cylinder.

A third aspect of the present invention is the developing device according to the first or second aspect, wherein the displacement suppressing member is in contact with at least a center of an axial length of the thin layer forming member.

According to a fourth aspect of the present invention, at least a part of the displacement suppressing member is on a side opposite to a side where the developer holding member is disposed with reference to a center of a cross section of the thin layer forming member. a developing device according to any one of claims 1 to 3, characterized in that contact with the layer forming member.

According to a fifth aspect of the present invention, there is provided an initial developer storage chamber in which a developer containing toner and a carrier is stored in a partition, a developer holding member that rotates while holding the developer on the surface, and the initial developer storage. A developer transport chamber in which the developer stored in the chamber flows and transports the developer to the developer holding member; and a part of the partition wall of the initial developer storage chamber, the initial developer storage chamber And a first developer supply for supplying the developer toward the developer holding member at least partly opened vertically above the developer holding member and mouth, and a partition wall having a second developer supply port for supplying the developer to the developer transport chamber provided between the said initial developer chamber the developer transport chamber, the first the developer supply port and the second developer supply port Resona A first sealing member and a second sealing member sealing a, respectively, and the thin layer forming member disposed to form a predetermined gap relative to said developer holding member, said thin layer Displacement that occurs when the developer is supplied from the first developer supply port and is arranged in contact with the forming member, and suppresses displacement in a direction in which the thin layer forming member is separated from the developer holding member. An image forming apparatus including a displacement suppressing member that is disposed in contact with the thin layer forming member, an image holding member that is supplied with the developer from the developer holding member, and that rotates while holding an image on the surface. is there.

A sixth aspect of the present invention is the image forming apparatus according to the fifth aspect, wherein the thin layer forming member is formed of a cylinder.

Invention of claim 7, wherein said displacement suppression members, image formation according to any one of claims 5 or 6, characterized in that contact with the center of the axial length of at least the thin layer forming member Device.

According to an eighth aspect of the present invention, at least a part of the displacement suppressing member is on a side opposite to a side where the developer holding member is disposed with reference to a center of a cross section of the thin layer forming member. The image forming apparatus according to claim 5 , wherein the image forming apparatus is in contact with a layer forming member.

According to the first aspect of the present invention, the amount of the developer supplied to the image holding member is suppressed from fluctuating depending on the supply state of the developer with respect to the developer holding member, as compared with the case without this configuration. can do. In addition , the amount of developer supplied to the image carrier can be increased with respect to the developer holding member even in a configuration in which the amount of developer held on the image carrier is likely to increase compared to the case without this configuration. Fluctuation depending on the supply state of the agent can be suppressed.
According to invention of Claim 2 , compared with the case where it does not have this structure, the displacement suppression of the thin layer forming member by a displacement suppression member can be performed more favorably.
According to the third aspect of the present invention, it is more preferable that the amount of the developer supplied to the image holding body varies depending on the supply state of the developer with respect to the developer holding member, as compared with the case without this configuration. Can be suppressed.
According to the fourth aspect of the present invention, the displacement of the thin layer forming member caused by the force generated when the developer is supplied rapidly is suppressed more satisfactorily than in the case where the present configuration is not provided. be able to.

According to the fifth aspect of the present invention, the amount of the developer supplied to the image holding member varies depending on the supply state of the developer with respect to the developer holding member, as compared with the case where this configuration is not provided. An image forming apparatus that can be suppressed can be provided. In addition , the amount of developer supplied to the image carrier can be increased with respect to the developer holding member even in a configuration in which the amount of developer held on the image carrier is likely to increase compared to the case without this configuration. Fluctuation depending on the supply state of the agent can be suppressed.
According to invention of Claim 6 , compared with the case where it does not have this structure, the displacement suppression of the thin layer formation member by a displacement suppression member can be performed more favorably.
According to the seventh aspect of the present invention, it is more preferable that the amount of the developer supplied to the image holding member varies depending on the supply state of the developer with respect to the developer holding member, as compared with the case where this configuration is not provided. Can be suppressed.
According to the eighth aspect of the present invention, the displacement of the thin layer forming member caused by the force generated when the developer is supplied rapidly is suppressed more satisfactorily than in the case without this configuration. be able to.

1 is a schematic configuration diagram illustrating an image forming apparatus according to an exemplary embodiment. It is a block diagram of the developing device according to the present embodiment. FIG. 4 is an enlarged view of the periphery of a developing roll and a trimmer member according to the present embodiment. It is a perspective view for demonstrating the trimmer member and displacement suppression member which concern on this Embodiment. It is the perspective view which removed the trimmer member of FIG.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
FIG. 1 is a schematic configuration diagram showing an image forming apparatus 1 according to the present embodiment.
The image forming apparatus 1 includes a plurality of image forming units 30 (30Y) of yellow (Y), magenta (M), cyan (C), and black (K) as an aspect of the image forming unit disposed in the image forming space 10. , 30M, 30C, 30K). Each image forming unit 30 (30Y, 30M, 30C, 30K) includes a photosensitive drum (image holding member) 31 and various electrophotographic devices sequentially arranged around the photosensitive drum 31. It is integrally formed and is a so-called cartridge. The integrally formed electrophotographic device includes, for example, a charging roll 32 for charging the photosensitive drum 31 and an electrostatic latent image formed by exposure on the photosensitive drum 31 charged by the charging roll 32. A developing device 33 for developing the toner, a cleaning device 35 for removing waste toner on the photosensitive drum 31, and the like. However, when forming the cartridge, for example, only the developing device 33 may have a separate structure, and a structure different from the cartridge of the photosensitive drum 31 may be used.

  Further, the image forming apparatus 1 includes an exposure unit 40 that exposes the photosensitive drum 31 using, for example, a laser beam as an aspect of the image forming unit. Further, the image forming apparatus 1 includes an intermediate transfer belt 51 to which each color toner image formed on the photosensitive drum 31 of each image forming unit 30 (30Y, 30M, 30C, and 30K) is transferred in a multiple manner, and each image forming unit. A primary transfer roll 52 that sequentially transfers (primary transfer) each color toner image formed at 30 (30Y, 30M, 30C, 30K) to the intermediate transfer belt 51. Further, the image forming apparatus 1 includes a secondary transfer roll 80 that collectively transfers (secondary transfer) a toner image formed on the intermediate transfer belt 51 in a superimposed manner onto a sheet P that is a recording material (recording paper). Yes. In addition, a fixing unit 81 that fixes the second-transferred toner image on the paper P is provided. Further, the image forming apparatus 1 includes a toner cartridge 20 that supplies toner to the developing device 33 of each image forming unit 30 (30Y, 30M, 30C, 30K). In addition, the image forming apparatus 1 includes a control unit 83 that controls the entire image forming apparatus 1.

  The image forming apparatus 1 executes a series of image forming processes under operation control by the control unit 83. That is, image data acquired from a PC, a scanner, or the like is subjected to image processing by an image processing unit (not shown) and sent to the exposure unit 40 as image data of each color. Each image forming unit 30 (30Y, 30M, 30C, 30K) receives exposure by the exposure unit 40 and is developed by the developing device 33 to form a toner image on the photosensitive drum 31. Each color toner image formed on the photosensitive drum 31 of each image forming unit 30 (30Y, 30M, 30C, 30K) is sequentially electrostatically transferred (primary transfer) onto the intermediate transfer belt 51 by the primary transfer roll 52. A superimposed toner image in which the toners of the respective colors are superimposed is formed. The superimposed toner image on the intermediate transfer belt 51 is conveyed to a secondary transfer region where the secondary transfer roll 80 is disposed as the intermediate transfer belt 51 moves. On the other hand, the paper P is fed in accordance with the transport timing of the superimposed toner image and transported to the secondary transfer area. The superimposed toner image on the intermediate transfer belt 51 is collectively electrostatically transferred (secondary transfer) onto the conveyed paper P by the transfer electric field formed by the secondary transfer roll 80 in the secondary transfer portion. Is done. The sheet P on which the superimposed toner image has been electrostatically transferred is conveyed to the fixing unit 81 and fixed on the sheet P by the fixing unit 81. The paper P after fixing is conveyed to a paper stacking unit provided in the discharge unit of the image forming apparatus 1.

Next, the developing device 33 of the image forming apparatus 1 will be described with reference to FIGS.
Here, FIG. 2 is a configuration diagram for explaining the developing device 33 according to the present embodiment. FIG. 3 is a configuration diagram for explaining the periphery of the developing roll 106 and the trimmer member 112 into which the developer according to the present embodiment has flowed. FIG. 4 is a perspective view for explaining the configuration of the trimmer member 112 and the displacement suppressing member 120 in the developing device 33, in which the initial developer storage chamber 101 and the stirring and conveying members 111A and 111B are removed. FIG. 5 is a perspective view in which the developer trimmer member 112 shown in FIG. 4 is removed.
Further, the developing device 33 described here can be similarly used for each of the image forming units 30 (30Y, 30M, 30C, 30K).

  As shown in FIG. 2, the developing device 33 is positioned above the developing device 33, and includes an initial developer storage chamber 101 that stores a developer G that is a two-component developer, and a lower portion of the initial developer storage chamber 101. And a developing roll chamber 102 for containing the stirred developer G, which is arranged next to each other. An agitating / conveying chamber 107 for agitating the developer G, which is an example of a developer conveying chamber, is provided below the developing roll chamber 102 and adjacent to the initial developer containing chamber 101. The developing roll chamber 102 is provided with a developing roll 106 for performing development against the photosensitive drum 31.

First, the initial developer storage chamber 101 will be described.
As shown in FIG. 2, the initial developer accommodating chamber 101 has a space formed therein so as to accommodate the developer G, and a filler inlet 131 is formed in the upper portion of the initial developer accommodating chamber 101. Has been. The developer G is charged into the initial developer accommodating chamber 101 through the filler charging port 131. In order to prevent the developer G from flowing out when the developing device 33 is conveyed, the filler inlet 131 is sealed by the sealing member 133 after the developer G is charged into the initial developer storage chamber 101. Has been.
Further, as described above, the initial developer storage chamber 101 is disposed adjacent to the developing roll chamber 102 and the agitating / conveying chamber 107, and is disposed above the developing roll chamber 102 and the agitating / conveying chamber 107. The initial developer accommodating chamber 101 and the developing roll chamber 102 are communicated with each other through the first opening 124. Further, the initial developer storage chamber 101 and the agitation transport chamber 107 are communicated with each other through the second opening 126.

  Here, a partition wall 130, which is a part of a partition that forms the initial developer storage chamber 101, is disposed between the initial developer storage chamber 101, the developing roll chamber 102, and the agitation transport chamber 107. The partition wall 130 forms a first opening 124 that is an example of a first developer supply port and a second opening 126 that is an example of a second developer supply port.

The first opening 124 is at least partially open above the developing roll 106. That is, the first opening 124 is formed vertically above at least a part of the developing roll 106. This is a configuration in which the developer G that has passed through the first opening 124 heads toward the developing roll 106 when it freely falls. With this configuration, the developer G flows directly from the initial developer storage chamber 101 into the developing roll chamber 102.
The first opening 124 is provided with a seal 122 that is heat-sealed in a state before use, which is an example of a first sealing member. The initial developer is used before, for example, transporting the apparatus. The developer G stored in the storage chamber 101 is configured to prevent the developer G from flowing into the developing roll chamber 102.
Further, the second opening 126 is provided with a heat-sealed seal 127 which is an example of a second sealing member, and the developer G accommodated in the initial developer accommodating chamber 101 is agitated and conveyed chamber 107. It is configured to prevent inflow.
In the present embodiment, the seal 122 provided in the first opening 124 and the seal 127 provided in the second opening 126 are separate members, but the seal 122 and the seal 127 are integrated. It may be configured. In the present embodiment, the seals (122, 127) are heat-sealed. However, in addition to the heat-sealing, for example, the seals are inserted into grooves provided around the openings (124, 126). The structure fixed by doing may be sufficient. The seals (122, 127) are formed of resin or paper.

Next, the developing roll chamber 102 will be described.
As shown in FIG. 2, the developing roll chamber 102 includes a developing roll 106 that is an example of a developer holding member, a trimmer member 112 that is an example of a thin layer forming member, and a displacement suppression member that suppresses displacement of the trimmer member 112. 120.

  First, the developing roll 106 is rotatably disposed so as to face the photosensitive drum 31 (see FIG. 1). A bias voltage is applied between the developing roll 106 and the photosensitive drum 31 to form an electric field, and the toner in the developer G moves toward the latent image on the photosensitive drum 31 during development. Has been.

The trimmer member 112 is configured to form a developer G (thin layer) having a predetermined height on the developing roll 106 by regulating the amount of the developer G that passes between the trimmer member 112 and the developing roll 106. Has been. In order to define the predetermined height, the outer peripheral surface of the trimmer member 112 and the outer peripheral surface of the developing roll 106 are arranged so as to form a substantially constant gap along the longitudinal direction of the trimmer member 112.
In the present embodiment, the trimmer member 112 is formed by a cylinder. As shown in FIG. 4, the trimmer member 112 has a large-diameter columnar portion 112A disposed at the center and small-diameter columnar portions 112B disposed at both ends of the large-diameter columnar portion 112A. Further, the trimmer member 112 is made of metal, and specifically is formed of stainless steel. Note that the trimmer member 112 in the present embodiment is arranged by, for example, inserting a small-diameter cylindrical portion 112B into through holes 135 (see FIG. 5) formed on both end surfaces in the axial direction of the developing device 33, and is fixed. However, it may be fixed by screwing the small-diameter cylindrical portion 112B.

  The displacement suppression member 120 is configured to suppress movement and deflection of the trimmer member 112 in a plane orthogonal to the longitudinal direction of the trimmer member 112 (a plane parallel to the paper surface of FIGS. 2 and 3). That is, the position variation of the trimmer member 112 with respect to the developing roll 106 is suppressed. In order to suppress this variation in position, one surface of the trimmer member 112 is disposed with its position fixed to a part 134 of the wall of the developing roll chamber 102, and the other surface is a large-diameter cylindrical portion of the trimmer member 112. It is arranged in contact with 112A.

Further, the displacement suppressing member 120 is arranged in contact with at least the center of the trimmer member 112 in the axial direction (a position where the length of the trimmer member 112 is half). In the present embodiment, the longitudinal direction of the displacement suppressing member 120 (the direction perpendicular to the plane of FIG. 2 and FIG. 3) is substantially parallel to the longitudinal direction of the trimmer member 112. Further, the displacement suppressing member 120 extends in the longitudinal direction of the trimmer member 112, and at least the longitudinal length of the region where the developing roll 106 holds the developer G (the length in the direction perpendicular to the paper surface in FIG. 2), The displacement suppressing member 120 is disposed in contact with the displacement suppressing member 120.
The displacement suppressing member 120 is on the side opposite to the side on which the developing roll 106 is disposed with reference to the center 112C of the cross section of the trimmer member 112, and is the cross section of the center 106C of the developing roll 106 and the trimmer member 112. It is arranged at a position that is biased toward the photosensitive drum 31 with respect to the line segment connecting the center 112C. The biased position toward the photosensitive drum 31 is determined by the main load direction received from the developer G.

  In the present embodiment, the trimmer member 112 is installed in the developing roll chamber 102 by inserting a small-diameter cylindrical portion 112B into the through hole 135, and the displacement suppressing member 120 is connected to the trimmer member 112 by contact with the trimmer member 112. It functions as a member that suppresses the rotation of the member 112. As a material of the displacement suppression member 120, for example, urethane can be adopted, but the material is not limited as long as the displacement suppression member 120 can prevent the movement of the trimmer member 112 by contact. For example, other materials such as resin and metal can be used. Materials may be used. As a specific configuration, a resin protrusion (rib) formed on a part 134 of the wall of the developing roll chamber 102 may be used.

Next, the stirring and conveying chamber 107 will be described.
As shown in FIGS. 2 and 4, the agitation transport chamber 107 is divided into the agitation transport chamber 107 </ b> A and the agitation transport chamber 107 </ b> B by a partition member 128 erected at the lower portion thereof. Then, a stirring and conveying path 108A and a stirring and conveying path 108B are formed in the stirring and conveying chamber 107A and the stirring and conveying chamber 107B, respectively. As shown in FIG. 4, the first communication port 109 and the second communication port 110 that are opened are provided at both ends of the partition member 128. Through the first communication port 109 and the second communication port 110, the stirring and conveying path 108A and the stirring and conveying path 108B communicate with each other. An upper portion of the stirring conveyance path 108 </ b> A is an opening and communicates with the developing roll chamber 102. Further, the upper surface of the agitation transport path 108B is an opening and communicates with the initial developer storage chamber 101. Note that the agitating / conveying chamber 107 and the developing roll chamber 102 may be integrated.
The end of the agitating / conveying path 108B on the second communication port 110 side protrudes from the end surface of the agitating / conveying path 108A toward the outside of the developing device 33 (see FIG. 4). It is configured to receive.

In the stirring and conveying chamber 107A and the stirring and conveying chamber 107B, a stirring and conveying member 111A and a stirring and conveying member 111B are arranged, respectively. The agitating / conveying member 111A has a rotating shaft (not shown) and blades (not shown) attached spirally to the outer periphery thereof. Similarly, the agitating / conveying member 111B has a rotating shaft (not shown) and a blade (not shown) attached to the outer periphery of the rotating shaft in a spiral shape opposite to the blade of the agitating / conveying member 111A.
The developer G in the agitating / conveying chamber 107 is mixed with the toner supplied from the toner cartridge 20 by rotating the agitating / conveying member 111A and the agitating / conveying member 111B by driving means (not shown). Furthermore, the developer G in the agitation transport chamber 107 is configured to circulate in the agitation transport path 108A and the agitation transport path 108B by rotating the agitation transport member 111A and the agitation transport member 111B.

Next, the operation of each component of the developing device 33 according to this embodiment will be described.
Prior to image formation, the developer G in the developing device 33 is accommodated in the initial developer accommodating chamber 101 and is not accommodated in the developing roll chamber 102 or the stirring and conveying chamber 107 (see FIG. 2). When the developing device 33 is disposed in the image forming apparatus 1 and the image forming apparatus 1 is used, a seal 122 that seals the first opening 124 formed in the lower portion of the initial developer storage chamber 101; The seal 127 that seals the second opening 126 is removed. When the seals 122 and 127 are removed, the developer G freely falls and flows into the developing roll chamber 102 and the agitation transport chamber 107. In the developing device 33 according to the present embodiment, since the developer G is directly supplied from the initial developer containing chamber 101 to the developing roll chamber 102, the second opening is used when the developing device 33 is used for the first time. The developer G is supplied to the developing roll 106 at an early stage without using the developer G supplied to the developing roll 106 from the section 126 through the path of the stirring and conveying chamber 107.

Here, the developer G that passes through the first opening 124 and flows into the developing roll chamber 102 will be described.
Since the first opening 124 is located above the developing roll 106, the developer G that freely falls through the first opening 124 moves toward the developing roll 106 in the developing roll chamber 102. The developer G that has moved toward the developing roll 106 is used for developing the photosensitive drum 31 as the developing roll 106 rotates.

  Here, immediately after the above-described seal 122 is removed, a large amount of developer G flows into the developing roll chamber 102 at a time, so that the developer G pushes the gap between the developing roll 106 and the trimmer member 112. A force in the direction in which the trimmer member 112 moves away from the developing roll 106 (see arrow D in FIG. 3), that is, a force that causes movement of the trimmer member 112 and bending of the trimmer member 112 is applied to the trimmer member 112. Here, when the gap between the developing roll 106 and the trimmer member 112 is pushed wide, the amount of the developer G on the developing roll 106 becomes larger than a predetermined amount, which may cause image quality defects.

However, in the present embodiment, the displacement suppressing member 120 contacts the trimmer member 112 on the side opposite to the side where the developing roll 106 is disposed with respect to the center 112C of the cross section of the trimmer member 112 as described above. Therefore, it is possible to apply a force to the trimmer member 112 so as to oppose the force that pushes the gap between the developing roll 106 and the trimmer member 112. Thereby, the displacement suppression member 120 can restrict the movement of the trimmer member 112 in a plane perpendicular to the longitudinal direction.
Furthermore, in the present embodiment, as described above, the length of the displacement suppressing member 120 (the direction perpendicular to the paper surface in FIG. 2) is substantially the same as the length in the longitudinal direction of the large-diameter cylindrical portion 112A of the trimmer member 112. Because of the length, it is possible to suppress the trimmer member 112 from being displaced over almost the entire region where the developing roller 106 holds the developer G.

  In this embodiment, the partition wall 130 of the initial developer accommodating chamber 101 has the first opening 124 and the second opening 126, but the partition wall 130 of the initial developer accommodating chamber 101 is the first. A configuration having only the opening 124 may be used. When the partition wall 130 has only the first opening 124, the developer G previously stored in the initial developer storage chamber 101 flows in order from the first opening 124 to the developing roll chamber 102 and the agitation transport chamber 107. After that, it will circulate. If this configuration is adopted, it is not necessary to provide the second opening 126 located above the agitation transport chamber 107, so that the degree of freedom in designing the initial developer storage chamber 101 is increased. As a result, for example, the arrangement and shape of the developing device 33 can be freely designed, and the developing device 33 can be downsized.

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 10 ... Image forming space, 33 ... Developing apparatus, 101 ... Initial developer storage chamber, 102 ... Developing roll chamber, 106 ... Developing roll, 107 ... Agitation conveyance chamber, 112 ... Trimmer member, 120 ... Displacement Inhibiting member, 122 ... seal, 124 ... first opening, 126 ... second opening, 127 ... seal, 128 ... partition member, 130 ... partition wall

Claims (8)

An initial developer storage chamber in which a developer containing toner and a carrier is stored in a partition;
A developer holding member that rotates while holding the developer on the surface;
A developer transport chamber in which the developer stored in the initial developer storage chamber flows and transports the developer to the developer holding member;
A part of the partition wall of the initial developer accommodating chamber, provided between the initial developer accommodating chamber and the developer holding member, and at least partially opened vertically above the developer holding member. And a first developer supply port for supplying the developer toward the developer holding member, and between the initial developer storage chamber and the developer transport chamber, and is developed in the developer transport chamber. A partition wall having a second developer supply port for supplying the agent;
A first sealing member and a second sealing member for sealing each of the first developer supply port and the second developer supply port;
A thin layer forming member disposed to form a predetermined gap with respect to the developer holding member;
Displacement that occurs when the developer is supplied from the first developer supply port and is in contact with the thin layer forming member, in a direction in which the thin layer forming member is separated from the developer holding member. A developing device comprising: a displacement suppressing member that suppresses displacement. The thin layer forming member, a developing apparatus according to claim 1, characterized in that it is formed by a cylinder. The displacement suppression member, a developing apparatus according to claim 1 or 2, wherein the contact with the center of the axial length of at least the thin layer forming member. The displacement suppressing member is at least partially in contact with the thin layer forming member on a side opposite to the side where the developer holding member is disposed with respect to the center of the cross section of the thin layer forming member. developing apparatus according to any one of claims 1 to 3, characterized. An initial developer storage chamber in which a developer containing toner and a carrier is stored in a partition;
A developer holding member that rotates while holding the developer on the surface;
A developer transport chamber in which the developer stored in the initial developer storage chamber flows and transports the developer to the developer holding member;
A part of the partition wall of the initial developer accommodating chamber, provided between the initial developer accommodating chamber and the developer holding member, and at least partially opened vertically above the developer retaining member. And a first developer supply port for supplying the developer toward the developer holding member, and between the initial developer storage chamber and the developer transport chamber, and is developed in the developer transport chamber. A partition wall having a second developer supply port for supplying the agent;
A first sealing member and a second sealing member for sealing each of the first developer supply port and the second developer supply port;
A thin layer forming member disposed to form a predetermined gap with respect to the developer holding member;
Displacement that occurs when the developer is supplied from the first developer supply port, and is disposed in contact with the thin layer forming member, in a direction in which the thin layer forming member is separated from the developer holding member. A displacement suppressing member for suppressing displacement;
An image forming apparatus comprising: an image holding member which is disposed in contact with the thin layer forming member, receives a developer supplied from the developer holding member, and rotates while holding an image on the surface. 6. The image forming apparatus according to claim 5 , wherein the thin layer forming member is formed by a cylinder. The image forming apparatus according to claim 5 , wherein the displacement suppressing member is in contact with at least a center of an axial length of the thin layer forming member. The displacement suppressing member is at least partially in contact with the thin layer forming member on a side opposite to the side where the developer holding member is disposed with respect to the center of the cross section of the thin layer forming member. The image forming apparatus according to claim 5 , wherein the image forming apparatus is an image forming apparatus.

Images