JPH04191768A - Developing device - Google Patents

Abstract

PURPOSE:To reduce the initial torque and improve the assembling property and the quality of image by integrally molding the rotating shaft and carrying part of a means for carrying a developer while stirring it in a developer receiving vessel by use of an elastically deformable member. CONSTITUTION:A developer stirring and carrying means 6 is formed of a rotating shaft and a developer carrying part, and integrally molded by use of an elastically deformable member. A developer (t) in a developer receiving part 5 is coagulated due to transportation and long-term leaving, and when the means 6 is rotated, the carrying part of the means 6 is deflected by receiving a large force in the direction opposite to the rotating direction and laid into the state wound on the rotating shaft. Therefore, the initial rotating torque is reduced, the means 6 can smoothly start rotation, and the developer (t) is also loosed. Thus, the carrying part of the means 6 is also elastically returned, and the developer (t) can be carried to an opening part 4. The assembling property is improved, the initial torque is reduced, and the quality of image can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a developing device applied to an image forming apparatus.

[Prior Art] In both image forming apparatuses using electrophotography, if the apparatus is used for a long period of time, it is necessary to replace the photoreceptor, replenish or replace the developer, clean the charging wire, or make other adjustments or replacements. . Such maintenance work had to be performed by service personnel with specialized knowledge. As a means to solve the above-mentioned problems, a cartridge type product has been commercialized that integrates image forming means such as a latent image carrier, a developing device, and a Kwaninck device.
General users can now perform replacement and maintenance themselves.

However, in order to reduce the running cost by extending the usable period of the cartridge as much as possible, it is necessary to increase the amount of developer, and there is a tendency to do so. Therefore, it is necessary to increase the size of the developing container in which the developer is placed, but in this case, the problem of retention of the developer arises.

Therefore, a means to prevent this was needed. As a solution to this problem, as shown in Figure 1I, a developing device is constructed of a rotating shaft, a conveying section for stirring and transporting the developer, and a member for pasting them together, in a developer storage section near the developing section. A method of providing a means for stirring and transporting the agent was proposed.

[Problem to be solved by the invention] However, as mentioned in -E, the conventional device had the following problems.

When process cartridges were first used, the developer solidified due to transportation and long-term storage of process cartridges, requiring higher rotational torque than normal. As a result, too much load is applied to the drive gear of the stirring shaft, causing the drive gear to crack, and the per-rotation torque not being constant, which affects the rotational fluctuations of the drive motor and causes uneven images. There was a point.

As a solution to this problem, the conventional method was to make the separate stirring part thinner and more elastic, and during the initial rotation, the stirring part was bent to loosen the toner and reduce the torque per rotation. .

However, in the conventional configuration, it is difficult to assemble the developer stirring and conveying means, and there is a risk that the stirring means may come off during rotation.

The present invention solves the above problems, reduces rotational torque, and
Another object of the present invention is to provide a developing device that is easy to assemble and has a developer stirring and conveying means that does not have the risk of coming off.

[Means for Solving the Problems] According to the present invention, the above-mentioned object has a developer storage container with an opening formed in the front, and is rotatably supported inside the developer storage container, In the developing device, the developer agitation and conveyance means transports the developer in the developer storage container to the opening without stirring the developer, wherein the developer agitation and conveyance means has a rotary shaft and a conveyance part that are elastically deformable. This is achieved by integrally molding the parts.

[Function] According to the present invention, since the rotary shaft of the developer agitation and conveyance means and the conveyance section are integrally molded as an elastically deformable member, even when the developer is solidified, the developer can be bent by the elastic force. Reduce by 1 to 1 rotation. Further, even when used for a long period of time, by integrally molding, only the conveying section will not fall off.

[Example] First to ninth embodiments of the present invention will be described based on the accompanying drawings.

<First Embodiment> First, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2.

FIG. 1 is a cross-sectional view of a process cartridge. l
2 is a photoreceptor, 2 is a developing screen serving as a developer carrier, 5 is a developer storage section, and 9 is a developing section. A developer t is stored in the developer storage section 5, and an opening 4 for feeding the developer t to the development section 9 is opened at the front. Inside the developer storage section 5, there is provided a developer stirring and conveying means 6 that rotates five times and conveys the developer t to the L recording port 4. The developer stirring and conveying means 6 is integrally molded from a member capable of elastic deformation D7. The developer t conveyed to the opening 4 by the developer agitation conveyance means 6 is transferred to the developing screen 2.
Due to the magnetic force of the Macnet inside, it is attracted to the developer sleeve 2, and further.

The structure is such that a latent image is developed on the surface of the photoreceptor.

Here, the operation of the stirring section at the initial stage of use of the cartridge will be explained.

As mentioned above, the developer t in the unused process cars 1 to 6 is solidified due to transportation and long-term transportation.

When the developer agitation and conveyance means 6 is rotated from this state, first, since the conveyance section of the developer agitation and conveyance means 6 is integrally molded with an elastically deformable member, the solidified developer is rotated in the opposite direction. When a large force is applied in that direction, it bends in that direction and becomes wrapped around the shaft for one rotation. For this reason, the initial rotational torque is reduced, and the developer stirring and conveying means 6 can start rotating smoothly. This rotation also loosens the developer t. Accordingly, the conveying portion that had been wrapped around the rotating shaft of the developer stirring and conveying means 6 also begins to return to its original shape due to the elastic force, and the developer t can be conveyed to the opening 4.

The developer stirring and conveying means 6 includes a rotating shaft and a developer conveying section, which are integrally molded as shown in FIG. 2.

Here, "integrated molding" means molding the shaft and wings at the same time using a material such as plastic. Because the shape of the shaft and the conveyor section is so uneven, it is difficult to mold it with normal molding, but if you use a gas injection method that injects high-pressure gas into the shaft after soaking, it is possible to eliminate this unevenness. The shape can also be easily molded. Regarding this molding, patent W
JNo.

It is described in.

Unlike conventional methods, this integrated cultivation method makes it possible to create a seamless developer agitation and conveyance means, so that when the developer agitation and conveyance means rotates, there is no resistance applied to the joints, and the device rotates smoothly. It is composed of

Conventionally, the cross-sectional shape of the developer stirring and conveying means had to be modified, such as by making a D-cut in the shaft for joining. Therefore, Neshir)ri! 4
However, the conveyance was not uniform due to the fact that the shaft was distorted due to twisting. However, in the present invention, since the shaft and the conveyance section are constructed in one piece, the cross-sectional shape of the developer agitation conveyance means is made circular to make it strong against torsion.

Furthermore, because of the integrated structure, there is no problem such as the stirring blades coming off during rotation as in the conventional case.

As described above, according to this embodiment, there is no risk of the conveyance unit falling off.
A developing device having a developer agitation conveyance means that can suppress rotational torque to a low level is provided.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIG. Note that the same reference numerals are used for the same parts as in the first embodiment, and the description thereof will be omitted.

The present embodiment shown in FIG. 3 differs from the first embodiment in that the developer conveyance section of the developer agitation conveyance means is curved in the radial direction in a cross section perpendicular to the rotation axis.

In the initial state of rotation as in the first embodiment, this embodiment employs a configuration in which the conveying section is curved in the radial direction as shown in FIG. 3, making the conveying section easy to bend.
During the initial rotation, the conveying section can more smoothly flex in the direction of wrapping around the shaft. Therefore, the initial rotational torque can be significantly reduced.

Further, by curving the stirring blade, the stirring blade can be made rigid in the direction of the stirring axis, and the straightness of the stirring blade in the direction of the stirring axis can be improved. Therefore, the developer can be transported more uniformly, and density unevenness due to differences in the amount of developer attached can be reduced.

Third Embodiment> Next, a third embodiment of the present invention will be described with reference to FIG. The same reference numerals are used for parts common to those in the first embodiment, and explanations thereof will be omitted.

The present embodiment shown in FIG. 4 differs from the first embodiment in that the thickness of the developer conveyance portion of the developer agitation conveyance means is uneven in the radial direction in a cross section perpendicular to the rotation axis.

It is very advantageous for conveyance to configure the developer conveyance section to come into contact with the inner wall of the developer storage section. but,
When the developer is brought into contact with the inner wall by normal compression, the developer is pressed between the inner wall of the developer storage portion and the conveyance means, and if this pressure is large, coarse particles are generated. These coarse particles damage the developing sleeve and significantly reduce image quality.

In this embodiment, the thickness of the developer conveyance section is uneven, and the tip is made thin. Therefore, the contact pressure can be reduced, and generation of coarse particles due to developer pressure can be prevented.

Moreover, by making the thickness even more uneven, the root of the developer transporting part can be thickened, stress can be concentrated at the root of the developer transporting part, and damage to the developer transporting part can be prevented.

<Fourth Embodiment> Next, a fourth embodiment of the present invention will be described using FIG. 5. The same reference numerals are used for parts common to those in the first embodiment, and explanations thereof will be omitted.

The present embodiment shown in FIG. 5 differs from the first embodiment in that a rift is provided in the developer conveyance portion of the developer agitation conveyance means whose thickness is uneven in the radial direction in a cross section perpendicular to the rotation axis. .

In this embodiment, by providing a riff on the stirring blade, an effect similar to that obtained by uneven thickness can be obtained. However, according to this method, unlike the case of uneven thickness, there is no fear of sink marks and less material is required, so it is possible to improve developer transportability at a small cost.

<Fifth Embodiment> Further, a fifth embodiment of the present invention will be described using FIG. 6. Note that the same reference numerals are given to the same parts as in the first embodiment, and the explanation thereof will be omitted.

The present embodiment shown in FIG. 6 differs from the first embodiment in that an opening is provided in the developer transport section of the developer agitation transport means.

As in the fourth embodiment, when the developer agitation and conveyance means starts rotating in a state in which the developer t is solidified at the beginning of rotation, the solidified developer t passes through the opening of the conveyance section due to unraveling force. For this reason, the developer t can be loosened more quickly, and the subsequent rotation of the developer agitation and conveyance means can be improved.

If an opening is provided in the conventional conveying section with uniform wall thickness,
This area becomes weak and may break, resulting in poor transportability. However, in the case of this embodiment, it is possible to make the developer easier to loosen while maintaining transportability by increasing the wall thickness of the opening by using the integrated mold, or by providing a rift on the side of the opening. Ru.

It should be noted that these embodiments can be combined to achieve even better effects. These can be easily realized because of the integrated cultivation type.

Sixth Embodiment Next, a sixth embodiment of the present invention will be described with reference to FIG. Note that the same reference numerals are given to the same parts as in the first embodiment, and the explanation thereof will be omitted.

This embodiment is not only capable of reducing the rotational torque as in the embodiment described above, but also solves the problem of residual developer.

Conventionally, the developer storage portion 5 has been formed to be thick in order to increase the amount of developer t, as shown in FIG. However, the opening 4 in the developer accommodating portion 5 for transporting the developer t to the developing chamber 3 is opened only to a width equal to the width of the print area perpendicular to the conveyance direction of the paper. In other words, the width of the developer storage section 5 is larger than the width of the opening 4.

The problem here is that since the width of the developer storage section 5 is larger than the width of the opening 4, some developer may remain at both ends of the developer storage section 5. It is impossible to use all of the developer effectively. A sensor is installed inside the developing chamber 9 to check the remaining amount of developer, but the sensor cannot detect the amount of developer that does not enter the developing chamber 9, and cannot accurately measure the remaining amount of developer. It cannot be detected. Therefore, the developer remaining in the developer storage section 5 is wasted.

This embodiment is intended to solve such problems,
The approximate S configuration is shown in FIG.

In this embodiment, as shown in FIG. 7, an auxiliary conveyance section 12 is provided at a certain angle on the side surface of the end of the developer conveyance section of the developer agitation conveyance means, and this is machined in one piece. It is characterized by

The conveying means rotates in the direction of the solid arrow shown in FIG. At this time, the developer at the end of the developer storage section receives a force from the auxiliary transport section 12 in the direction of the illustrated broken line arrow. In other words, the auxiliary conveyance section 12 is
The developer outside the opening area of the opening 4 is conveyed to the opening area. Therefore, the developer in the developer accommodating portion can finally be used without wasting it.

In other words, this embodiment not only suppresses the rotational torque but also solves the problem of developer remaining in the developer accommodating portion during developer transport.

<Seventh Example> Next, a seventh embodiment of the present invention will be described with reference to FIG.

Note that the same reference numerals are given to the same parts as in the sixth embodiment, and the explanation thereof will be omitted.

The present embodiment shown in FIG. 8 differs from the sixth embodiment in that the developer conveyance section of the developer agitation conveyance means is curved in the axial direction in a cross section parallel to the rotation axis.

In the sixth embodiment, the end height was bent, but
In this embodiment, the entire conveying section is curved with a certain curve, and the curvature increases as it goes toward the end.In this embodiment, the developer remaining at the end is stirred. As the conveying means rotates, a force is applied from the curved portion at the end of the conveying section in the direction of the broken line arrow, as shown in FIG. The developer remaining at the end is then gathered within the area of the opening. Furthermore, in the case of this embodiment, the conveying section is curved with a gentle curvature from the end to the center. For this reason,
The problem with the developing section is that the developer gathers in the center of the conveyance section, and the density is low in the center of the image area, but this is because the developer in the developer storage section is difficult to convey to the center. It happens because of this.

In this embodiment, it is possible to solve the problem of residual developer at the edges and to collect the developer in the center where image density tends to be low.

<Eighth Example> Next, an eighth embodiment of the present invention will be described using FIG. 9.

Note that the same reference numerals are given to the same parts as in the sixth embodiment, and the explanation thereof will be omitted.

The present embodiment shown in FIG. 9 differs from the sixth embodiment in that the developer conveyance section of the developer agitation conveyance means has uneven thickness in the axial direction in a cross section parallel to the rotation axis. .

In this embodiment, as shown in FIG.
The thickness is uneven in the axial direction and in the half-frame direction of the shaft toward the end of the conveying section.

In this embodiment, by rotating the developer agitation and conveyance means, the developer in the developer storage section receives force in the direction of the dashed arrow as shown in FIG. Further, in this embodiment, as shown in FIG. 9, the tip of the conveying section is flattened to make the conveying section easy to bend. Therefore, in the initial state of rotation, the conveying section can be more smoothly bent in the direction of wrapping around the shaft. Therefore, the initial rotational torque can be significantly reduced.

Ninth Embodiment Next, a ninth embodiment of the present invention will be described using FIG. 10. Note that the same reference numerals are given to the same parts as in the sixth embodiment, and the explanation thereof will be omitted.

The present embodiment shown in FIG. 10 is characterized in that second and third conveyance sections 13 as auxiliary conveyance means are provided as developer agitation conveyance means in addition to the developer main conveyance section.

The difference from this embodiment and the sixth embodiment is that, as shown in FIG. The point is that

In this embodiment, as the developer agitation and conveyance means rotates, the developer in the developer storage section receives a force in the direction of the dashed arrow as shown in FIG.

The developer is conveyed toward an opening area formed in the image area.

Moreover, since the auxiliary conveyance section 13 is divided into the opposite side of the main conveyance section, the elastic force of the main conveyance section can be made uniform in the axial direction. Therefore,
It is possible to eliminate unevenness in the amount of developer conveyed due to differences in the way the conveyance section flexes.

Furthermore, in this embodiment, as shown in FIG. 10, the main conveyance section is flat in the axial direction, so that the conveyance section is more easily bent in the direction of wrapping around the shaft than in the sixth embodiment. . Therefore, in the initial state of rotation, the conveying section can be more smoothly bent in the direction of wrapping around the shaft. Therefore, the initial rotational torque can be significantly reduced.

[Effects of the Invention] As explained above, according to the present invention, by integrally molding the developer stirring and conveying means, the ease of assembly can be greatly improved. In other words, it has become possible to significantly reduce costs.

Further, by changing the shape of the conveying section by integral molding, it has been possible to create a special shape to solve conveyance problems such as developer residue during developer conveyance. Furthermore, the image quality has been significantly improved by significantly reducing the initial torque and eliminating unevenness in the image.

Furthermore, because of the integrated structure, there is no problem such as the stirring blades coming off during rotation, unlike in the past.

This invention realizes cost reduction with a simple configuration, and also makes it possible to solve problems in conveyance during rotation. In other words, it has become possible to provide users with an electrophotographic device with good image quality at a low price.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a schematic configuration of a first embodiment of the present invention;
2 is a perspective view showing a schematic structure of the developer agitation and conveyance means of the apparatus shown in FIG. 1; FIG. 3 is a perspective view showing a schematic structure of the developer agitation and conveyance means of the second embodiment of the present invention; FIG. 5 is a perspective view showing a schematic configuration of a developer agitation and conveyance means according to a fourth embodiment of the present invention; FIG. FIG. 7 is a perspective view showing a schematic configuration of a developer agitation and conveyance means according to a sixth embodiment of the present invention; FIG. 9 is a perspective view showing a schematic structure of a developer agitation and conveyance means according to a seventh embodiment of the present invention; FIG. 9 is a perspective view showing a schematic structure of a developer agitation and conveyance means according to an eighth embodiment of the present invention; This figure is a perspective view showing a schematic structure of a developer agitation conveyance means according to a ninth embodiment of the present invention, and FIG. 11 is a sectional view showing a schematic structure of a conventional device. 6...Developer stirring and conveying means t...Developer

Claims (9)

[Claims] (1) It has a developer storage container with an opening formed in the front, is rotatably supported inside the developer storage container, and is moved to the opening while stirring the developer in the developer storage container. A developing device having a developer agitation and conveyance means for conveying the developer, wherein the developer agitation and conveyance means has a rotating shaft and a conveyance section integrally molded with an elastically deformable member. (2) The developing device according to claim 1, wherein the developer conveyance section of the developer agitation conveyance means is curved in the radial direction in a cross section perpendicular to the rotation axis. (3) The developing device according to claim 1, wherein the developer conveyance section of the developer agitation conveyance means has an uneven thickness in the radial direction in a cross section perpendicular to the rotation axis. (4) The developing device according to claim (1), wherein the developer transporting portion of the developer stirring and transporting means is provided with a rib having uneven thickness in the radial direction in a cross section perpendicular to the rotation axis. (5) The developing device according to claim (1), wherein the developer transport section of the developer agitation transport means is provided with an opening. (6) The developing device according to claim (1), wherein an auxiliary conveyance section is provided on an end side surface of the developer conveyance section of the developer agitation conveyance means. (7) The developing device according to claim (1), wherein the developer conveyance section of the developer agitation conveyance means is curved in the axial direction in a cross section parallel to the rotation axis. (8) The developing device according to claim (1), wherein the developer conveyance section of the developer agitation conveyance means has an uneven thickness in the axial direction in a cross section parallel to the rotation axis. (9) The developing device according to claim (1), wherein the developer agitation and conveyance means is provided with at least one auxiliary conveyance section integrally molded as an auxiliary conveyance means in addition to the developer conveyance section.