JP7624157B2 - Powder container, developing device and image forming apparatus - Google Patents

Description

The present invention relates to a powder storage container, a developing device, and an image forming device.

2. Description of the Related Art A powder storage container is known that includes a rotating member having a flexible member capable of rubbing against the inner surface of the container.
For example, Patent Document 1 describes such a powder storage container in which a flexible sheet is attached to a rotating member. The flexible sheet is bent at an intermediate position between the attachment portion and the tip. This shape is said to absorb deformation of the flexible sheet and prevent plastic deformation at the attachment end of the flexible sheet to the rotating member.

Powder storage containers come in a variety of shapes for their inner surfaces, and it is desirable to further improve the sliding properties of the tip of the flexible member against the inner surface of the container.

In order to solve the above-mentioned problems, the present invention provides a powder storage container equipped with a rotating body having a flexible member capable of rubbing against the inner surface of the container, the flexible member being composed of a first sheet member attached to the rotating member of the rotating body and a second sheet member attached to a location of the first sheet member other than the location connected to the rotating member, at least one of the first sheet member and the second sheet member having a bent portion that makes the distance between the tip of the second sheet member and the rotating member variable through deformation, and a rail member being provided between the opposing surfaces of the first sheet member and the second sheet member that face each other .

The present invention makes it possible to improve the sliding properties of the inner surface of the container compared to conventional methods.

FIG. 1 is a schematic diagram of an image forming apparatus. FIG. FIG. 2 is a schematic configuration diagram of a powder storage container according to the embodiment. 11A to 11C are explanatory diagrams of various modified examples. FIG. FIG. 13 is an explanatory diagram showing another configuration in which a rail member is provided.

One embodiment of an image forming apparatus using the powder storage container of the present invention will be described. FIG. 1(a) is a schematic diagram of the image forming apparatus. This image forming apparatus is a typical monochrome image forming apparatus, and a black process cartridge 101 is removably mounted in the image forming apparatus main body 100. Also arranged within the image forming apparatus main body 100 are an exposure device 104, a transfer roller 112, a paper feed tray 121, a fixing device 130, and the like.

When printing on one side, a latent image is formed on the photoconductor 102 as an image carrier by the exposure device 104, and a toner image is created inside the process cartridge 101. When the transfer process begins, the paper P held in the paper feed tray 121 is transported to the registration roller pair 123 by the paper feed roller 122. The registration roller pair 123 then adjusts the amount of paper P sent out so that the leading edge of the paper P coincides with the toner image at the nip position between the photoconductor 102 and the transfer roller 112 as a transfer member. A transfer bias is applied to the transfer roller 112 to transfer the toner image onto the paper P sent out by the registration roller pair 123.

Since the paper P that has passed through the transfer nip is charged by the transfer bias, it is neutralized by a neutralization needle 113 that acts as a neutralizing member. This causes the paper P to be separated from the photoconductor 102 or the transfer roller 112, and the paper P is transported to the fixing device 130. The toner image transferred by the heat and pressure of the fixing device 130 is fused to the paper P. The paper P that has passed through the fixing device 130 is discharged by a paper discharge roller 124 to a paper discharge tray 125 outside the machine.

During double-sided printing, the discharge rollers 124 are stopped once the rear end of the paper P with the first side printed passes the separation claw 126, and after switching the separation claw 126, the discharge rollers 124 are rotated in the opposite direction to send the paper P into the double-sided path 127. The paper P transported along the double-sided path 127 is transported again to the pair of registration rollers 123, and the second side is printed in the same process as for single-sided printing.

The developer container 200 is provided as a powder container that contains powder developer to be replenished to the developing device 101a of the process cartridge 101. The developer container 200 shown in the figure has a developer transport screw 220 near the developer supply port to the developing device 101a. The developer container 200 also has a stirring member 210 as a rotating body having a flexible member that can rub the inner surface of the container. In the example shown in the figure, a waste toner storage section 201 is integrally provided at the bottom of the developer container 200. The developer container 200 may store only toner, or if the developing device 101a uses a two-component developer, it may store a so-called premix developer, which is a two-component developer with a higher toner concentration than the toner concentration used for development. The toner or premix developer corresponds to the developer stored in the developer container.

Figure 1(b) is a perspective view showing the basic internal structure of the developer container 200. The agitating member 210 has a rotating shaft 211 as a rotating member and a sheet-like flexible member 230 attached to the rotating shaft 211. The agitating member 210 rotates in the direction indicated by arrow A, rubbing against the inner surface of the container, particularly the bottom surface, while agitating the developer and transporting the developer toward 220.

In the illustrated example, the flexible member 230 is divided into multiple pieces in the direction of the rotation center line 211a of the rotating shaft 211, and adjacent flexible members 230 are attached so as to extend radially from angular positions of the rotating shaft 211 that differ by 180 degrees. A single sheet-like flexible member 230 may be provided without being divided into multiple pieces. Dividing it into multiple pieces is preferable for improving the sliding properties when the shape of the inner surface of the container that is rubbing is different from the other parts in at least a part in the direction of the rotation center line 211a, as it makes it possible to set a radial length suitable for each shape.

Here, we will explain a typical developer container equipped with an agitator having this type of flexible member. In an image forming device, in a configuration in which developer is replenished from a developer container to a developing device, the agitator rotating in the developer storage section inside the container transports the developer along the transport path of a transport member such as a screw, which then rotates toward an outlet to transport the developer, which then drops from the outlet and replenishes it to the developing device. The agitator is often configured by attaching a flexible sheet to a shaft made of resin or metal. The configurations of the developer container and the agitator can be broadly divided into two patterns: one in which the tip is in contact with the inner wall of the container, and one in which there is a gap between the tip and the inner wall.

In the case of a pattern that is in contact with the container's inner wall, the shape of the inner wall is often an arc shape with the axis of the stirring member as the center of rotation of the toner containing section, so as to make it easier to stir the developer. However, in order to use the space in the developer containing container efficiently (for example, a configuration in which a transfer residual developer containing section is provided inside the developer containing container), there are also configurations in which the bottom of the developer containing section is not arc-shaped but has corners and the axis of the stirring member is not the center of rotation.

In configurations where the shaft of the stirring member is not at the center of rotation, for example because there are corners on the inner wall of the container, it is possible to allow developer to remain in the corners, or as a solution, a technique is known in which the tip of the stirring member is bent so that it can reach the corners and scrape off the developer.

However, in the conventional configuration where the axis of the stirring member is not at the center of rotation, when a stirring member with a bent tip is used, the amount of penetration into the inner wall changes as the stirring member rotates, so it is not possible to scrape off with a uniform strength, and when the developer in the container becomes low, the flexible sheet of the stirring member is bounced off the inner wall, causing noise. In addition, if the stirring member is stopped for a long time at a part where it is penetrating the inner wall a lot, the flexible sheet of the stirring member becomes significantly deformed and develops a tendency, resulting in poor developer scraping performance.

Figure 2 is an explanatory diagram of an example of the shape of the inner surface of the container. Figure 2(a) is an example in which the bottom surface inside the storage section is an arc. The tip of the flexible member 230 contacts the inner bottom surface almost evenly. The developer on the upper side of the container falls due to gravity. Figure 2(b) is an example in which the inner bottom surface is not an arc. The degree of contact with the inner bottom surface of the agitating member 210 varies depending on the rotational position of the agitating member 210. When the developer in the storage section becomes low, the sheet may bounce off the inner wall of the container, making a noise, or the sheet may deform when left unused for a long time, making it difficult to scrape off the developer.

Figure 3 is a schematic diagram of the developer container 200, which is a powder container according to this embodiment. If Figure 1 is a front view, Figure 3 corresponds to a rear view. The developer container 200 according to this embodiment includes a flexible member 230 composed of a first sheet member 231 attached to the rotating shaft 211 and a second sheet member 232 attached to a portion (free end) of the first sheet member 231 other than the portion connected to the rotating shaft 211. Both the first sheet member 231 and the second sheet member 232 are made of sheet-like flexible members. The flexible member 230 includes a bent portion C on at least one of the first sheet member 231 and the second sheet member 232, which changes the distance L between the tip of the second sheet member 232 and the rotating shaft 211 by deformation. The tip rubbing against the inner wall surface of the container moves in a translational manner as shown by the arrow B due to the change in distance L.

Due to the elasticity of the bent portion C, even if the distance between the rotating shaft 211 and the inner wall surface changes due to the rotation of the stirring member 210, the tip of the second sheet member 232, which is in a state where it can move toward the inner wall surface of the container, continues to contact the inner wall surface of the container, so that developer in the corners of the container can be scraped off without leaving any behind. The end (base end) of the second sheet member 232 on the rotating shaft 211 side may be joined or connected to the first sheet member 231 with a fixed member to be integrated, or may be integrated by welding using heat or bonding with an adhesive. Attaching the second sheet member 322 to the first sheet member 321 is called a connection, and the part where they are joined or otherwise connected to each other is called a connection part.

In the example of FIG. 3(a), the tip of the second sheet member 232 is straight, whereas in the example of FIG. 3(b), a tip bend 233 is provided at the tip of the second sheet member 232. In the example shown in FIG. 3, the bend C is provided in the second sheet member 232, but instead of or in addition to this, the bend C may be provided in the first sheet member 231.

Figure 4 shows various modified examples. As in the example of Figure 3(a), developer may get into space D on the inner side, which is the opposing space of bent portion C, and this may impede the movement of the leading edge of the sheet or prevent the accumulated developer from being discharged completely. To prevent this, bent portion C is formed so that space D is generated by bent portion C between the opposing surfaces of first sheet member 231 and second sheet member 232 when no external force is applied to flexible member 230. This allows space D to be blocked by the other sheet member in the direction perpendicular to the surface of the sheet.

As shown in the example of FIG. 4(a), the sheet having the bent portion C and the other sheet are arranged so as to overlap the bent portion C in a direction perpendicular to the plane of the sheets. In the example of FIG. 4(a), the tip 231a of the first sheet member 231 is positioned further toward the tip side than the bent portion C of the second sheet member 232. This causes the space D to be blocked by the first sheet member 231 in a direction perpendicular to the plane of the sheets. The base end of the second sheet member 232 is joined to the first sheet member 231 in all or part of the range indicated by the symbol E in the figure.

The example in FIG. 4(b) is an example in which a bent portion C is provided in the first sheet member 231. The first sheet member 231 is joined to the second sheet member 232 within a range E in which the portion of the first sheet member 231 that is further distal than the bent portion C faces the second sheet member 232. It is preferable that the end position 232a on the proximal side of the second sheet member 232 is positioned closer to the rotation axis 211 than the bent portion C of the first sheet member 231, and that the space D inside the bent portion C is blocked by the free proximal end of the second sheet member 232.

Figure 4 (c) shows an example in which a bent portion C is provided on both the first sheet member 231 and the second sheet member 232. In this case, it is preferable to close the space inside each bent portion C with the other sheet member. In the example shown, they are joined within range E, and the position of the tip 231a of the first sheet member and the end 232a on the rotating shaft side of the second sheet member 232 are set to a position that closes the space D.

Figure 5 is an explanatory diagram of yet another example. Figure 5(a) is a schematic diagram, Figure 5(b) is a perspective view of the stirring member 210, and Figure 5(c) is a cross-sectional explanatory diagram of the main parts. In this configuration example, a rail member 240 is provided between the opposing surfaces of a first sheet member 231 and a second sheet member 232. The rail member 240 is provided on the opposite side of the connection portion between the first sheet member and the second sheet member, sandwiching the bent portion, in the radial direction from the center of rotation of the rotating shaft.

The rail member 240 consists of a rail body 241 and a slide rail 242 slidably attached to the rail body 241. The slide rail 242 is configured so that it can slide relative to the rail body 241 but cannot separate in a direction perpendicular to the sliding direction. Providing such a rail member 240 prevents the two sheet members from separating, restricting the overall deflection of the two sheet members, and makes it easier to convert the force applied to the tip of the second sheet by the inner wall surface of the container into a moving force in the direction of expansion and contraction of the second sheet (the direction in which the distance between the rotation axis can be changed), allowing the tip to move forward and backward smoothly. Note that the symbol E1 in Figure 5(c) indicates a connection part formed by joining or the like.

Figure 6 shows another configuration in which a rail member 240 is provided. Figure 6(a) is an example in which a bent portion C is provided on the first sheet member 231 side. Figure 6(b) is an example in which the connection point of the slide rail 242 of the rail member 240 is located within the bent portion C in the direction of the distance L between the rotating shaft 211 and the tip of the second sheet member 232. The rail body 241 that is paired with the slide rail 242 and is connected to the first sheet member 231 in which the bent portion C is formed is connected to the first sheet member 231 on the opposite side of the bent portion C to the connection portion E1 of both sheet members. Therefore, it can be said that the rail member 240 is provided on the opposite side of the connection portion between the first sheet member and the second sheet member, across the bent portion, in the radial direction from the center of rotation of the rotating shaft.

Figure 6 (c) shows an example of a configuration in which the second sheet member 232 provided with the bent portion C is divided into multiple pieces. By dividing it in this way, even if the shape of the container inner wall differs in the central axis direction of the rotating shaft 211, each divided second sheet member 232 can move in accordance with the shape of each inner wall surface. The divided second sheet members 232 may be set so that their lengths in the direction perpendicular to the rotating shaft 211 are different from each other, and the shapes of the bent portions C may also be set so that they are different from each other.

Each of the illustrated examples above can also be expressed as follows.
(Aspect 1) A developer container comprising a developer container and a stirring member for stirring the developer in the container by rotation, the stirring member being composed of two sheets, the first sheet being fixed to an axis, the second sheet being installed so as to be expandable in a direction perpendicular to the axis relative to the first sheet, either the first sheet or the second sheet or both having a bent portion, the second sheet being biased in a direction away from the axis perpendicular to the axis by the elasticity of the bent portion. According to this, the second sheet comes into contact with the container inner wall by the rotation of the stirring member, and expands and contracts according to the shape of the inner wall, so that the stirring member can always come into contact with the inner wall with a constant amount of bite, and it is possible to prevent the stirring member from biting into the inner wall too much, resulting in a popping sound or deformation. Even if the inner wall of the developer container has a complex shape, the stirring member can come into contact with the inner wall with a uniform amount of bite, stabilizing the developer scraping performance and reducing the amount of developer remaining in the container after use.

(Aspect 2)
In (Aspect 1), a configuration in which a rail member is provided between two sheets makes it easier to transmit the elastic force of bending, suppresses the frictional force between the sheet and the inner wall of the container due to rotation and the deflection of the sheet due to toner agitation, and makes it easier for the second sheet to move in the direction perpendicular to the axis.

(Aspect 3)
In (Mode 1 or Mode 2), when the inside of the bent portion overlaps with the other sheet in a direction perpendicular to the axis, it is possible to prevent developer from entering the bent portion and interfering with the movement of the leading edge of the sheet or preventing accumulated developer from being discharged to the end.

(Aspect 4)
In (Aspects 1 to 3), in a configuration in which the tip of the stirring member sheet on the side of the stirring member that contacts the inner wall of the developer storage container is bent, bending the tip of the stirring member sheet on the side that contacts the inner wall of the second container increases the contact surface area with the inner wall, allowing for more stable contact.

(Aspect 5)
In (Modes 1 to 4), in a configuration in which the second sheet of the stirring member is divided into multiple sheets, each having a bent portion, the second stirring member sheet is divided into multiple sheets, so that even if the container shapes differ horizontally to the axis, the second sheet can move to accommodate each shape.

57: Stirring member 100: Image forming apparatus main body 101: Process cartridge 101a: Developing device 102: Photoconductor 104: Exposure device 112: Transfer roller 113: Discharge needle 121: Paper feed tray 122: Paper feed roller 123: Registration roller pair 124: Paper discharge roller 125: Paper discharge tray 126: Separation claw 127: Double-sided path 130: Fixing device 0146: Paragraph 200: Developer storage container 201: Waste toner storage section 210: Stirring member 211: Rotating shaft 211a: Rotation center line 220: Developer transport screw 230: Flexible member 231: First sheet member 231a: Tip 232: Second sheet member 232a: End 233: Tip bent portion 240: Rail member 241: Rail main body 242 : Slide rail 321 : First sheet member 322 : Second sheet member C : Bent portion D : Space E : Range E1 : Connection portion L : Distance P : Paper

JP 2001-166576 A

Claims (8)

A powder storage container having a rotating body having a flexible member capable of rubbing against the inner surface of the container,
The flexible member is composed of a first sheet member attached to a rotating member of the rotating body, and a second sheet member attached to a portion of the first sheet member other than a portion connected to the rotating member,
a bent portion is formed in at least one of the first sheet member and the second sheet member, the bent portion being capable of varying a distance between a tip end portion of the second sheet member and the rotating member by deformation ;
A powder storage container, comprising : a rail member provided between opposing surfaces of the first sheet member and the second sheet member, the opposing surfaces being opposed to each other . 2. The powder storage container according to claim 1 ,
A powder storage container characterized in that the rail member is arranged on the opposite side of the connection portion between the first sheet member and the second sheet member, across the bent portion, in a radial direction from the center of rotation of the rotating member. The powder storage container according to claim 1 or 2 ,
A powder storage container, comprising: a tip bent portion provided at a tip portion of the second sheet member. The powder container according to any one of claims 1 to 3 ,
A powder storage container characterized in that the second sheet member is divided into multiple pieces in the direction of the rotation center line of the rotating member, and the bent portion is formed in each of the divided sheet members. The powder storage container according to any one of claims 1 to 4 ,
A powder storage container, characterized in that the shape of the inner surface of the container that is rubbed by the second sheet member is different from other parts in at least a part in the direction of the rotation center line of the rotating member. The powder storage container according to any one of claims 1 to 5 ,
A powder container for storing a developer as powder. A developing device comprising the powder container according to any one of claims 1 to 6 . An image forming apparatus comprising the developing device according to claim 7 .

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