JP3527024B2 - Developing device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device. More specifically, in an image forming apparatus such as a copying machine using an electrophotographic system, a laser beam printer, a facsimile machine, or a composite machine thereof, a developer stirred by rotation of a paddle passes through a developer carrier and a latent image carrier. The present invention relates to a developing device for developing an electrostatic latent image by supplying the electrostatic latent image to the developing device.

[0002]

2. Description of the Related Art As a conventional developing device, for example, a blade plate is continuously provided on the upstream side in the rotation direction of a developer guiding member provided on the outer periphery of a developer stirring plate, and the blade plate surrounds the developer stirring plate. The developer is squeezed to the center of rotation to improve the mixing of the toner and the carrier, improve the charging efficiency of the toner, and improve the uniformity of the toner in the axial direction. A technique for obtaining stable development is known (see Japanese Utility Model Publication No. 1-135450). 9 and 10 are a horizontal cross-sectional view and a front vertical cross-sectional view showing the configuration of the essential parts of a conventional developer stirring and pumping rotary member. In this conventional example, the end portions of the developing roller 102 are provided by providing cylindrical rod-shaped fins 104 at 180 ° intervals at the disk portions provided at the axially opposite end portions 103a of the developer stirring / pumping rotary member 103. The developer (D) in the vicinity of both ends 103a of the developer agitating and pumping rotary member 103 is scraped away from the developing roller 102 so that the developer from the side plate 101a of the developing container 101 and the end of the developing roller 102 can be removed. A technique is also known in which (D) is prevented from leaking or overflowing, or the occurrence of locking or the like due to intrusion of the developer (D) into the bearing 102b of the developing roller 102 or the bearing 103b of the developer stirring / pumping rotating member 103. (See the official gazette of Japanese Utility Model Laid-Open No. 3-45556).

FIG. 11 is a plan view showing the positional relationship between the rotating member and the developing roller and the flow of the developer. Based on this figure, the developer stirring / pumping rotating member 103 transfers to the developing roller 102, and further the developer. The positional relationship of the developer (D) moving to the agitating and pumping rotary member 103 will be described. The developer (D) conveyed to the developing roller 102 with a width of x moves on the developing roller 102 with a width y that is substantially the same as the width of the magnet 102a inside the developing roller 102, and separates from the developing roller 102. After that, the developer stirring pumping rotary member 1
It will be collected by 03. Developer (D)
The amount of developer (D) for which the width in which the toner is conveyed is increased (y-x)
In order to convey the toner to the toner mixing and stirring area, the fins 104 are provided on the disk portions of both ends 103a of the developer stirring and pumping rotary member 103.
By providing, the developer (D) in the vicinity of both ends 103a of the developer stirring / pumping rotary member 103 is scraped from the end of the developing roller 102 in the direction away from the developing roller 102. In FIG. 12, however, the bulk of the developer (D) is higher than the height indicated by the arrow h1 by the height h2.
And the height h3 is further increased to a height h2, the remaining amount is increased, and the developer container 10 is used during maintenance or the like.
1 is inclined, or the developer container 101 is vigorously set in the axial direction of the developer stirring and pumping rotary member 103, or too much developer (D) is erroneously added, and the developer (D) is biased to one side. If so, the scraping effect by the fins is reduced, and the developer (D) separated from the developing roller 102 cannot be collected. As a result, the side plate 1 of the developing container 101 is removed.
01a and the end portion of the developing roller 102, the developer (D) leaks or overflows, or the developer (D) enters the bearings 102b and 103b to cause a lock (unrotatable). It was

[0004]

In the above-described conventional developing device, the remaining amount increases as the volume of the developer accumulated on the side plate side in the developing container increases, and the developing container tilts during maintenance or the like. If the developer container is vigorously set in the axial direction of the paddle of the rotating member, or if too much developer is accidentally added and the developer is biased to one side, the scraping effect will decrease and the developer will move away from the developing roller. There is also a problem that the developer cannot be collected and the developer leaks or overflows from the side plate of the developing container and the end of the developing roller, or the bearing locks due to the intrusion of the developer. Then, the subject of this invention is solving such a problem. That is, even if the developer becomes bulky or deviated to the side plate side of the developing container and the end of the developer carrier, the developer near the both ends of the paddle is developed from the end of the developer carrier. An object of the present invention is to provide a developing device capable of preventing a developer from leaking or overflowing, or preventing a bearing from being locked due to invasion of the developer by scraping a large amount in a direction away from the agent carrier in a short time. ing.

[0005]

To achieve the above object, the present invention according to claim 1 provides a developing container for containing a developer, a paddle rotatably arranged in the developing container, and a rotation of the paddle. And a developer carrying member that carries the developer supplied to the peripheral surface while being stirred by the above and conveys it to the developing region, and is formed on the latent image carrying member by the developer conveyed to the developing region by the developer carrying member. In the developing device for developing the formed electrostatic latent image, one end is fixed to the axial end of the paddle .
It has a rod shape and has a gap with the rotation axis of the paddle.
In the configuration, a developer scraping unit that scrapes away the developer that has moved from the developer carrier and accumulated between the end of the paddle and the side plate of the developer container in a direction away from the developer carrier, and the developer scraping unit. provided on the other end side and having a developer regulating means for regulating the movement of the developer to the side plate of the developer container from the end portion side of the paddle. According to a second aspect of the present invention, in the developing device according to the first aspect, the developer restricting means allows the developer to move from the side plate side of the developing container to the end side of the paddle. The main feature is that the developing device has a notch. According to a third aspect of the present invention, in the developing device according to the second aspect, the cutout portion is provided at a position downstream of the developer scraping unit in the rotation direction of the developer regulating unit. That is the main feature. A fourth aspect of the present invention is characterized in that, in the developing device according to the first, second or third aspect, the developer scraping means is a developing device having a cylindrical cross section. A fifth aspect of the present invention is characterized in that, in the developing device according to the first, second or third aspect, the developer scraping means is a developing device having a quadrangular prism shape in cross section. According to a sixth aspect of the present invention, in the developing device according to the first, second or third aspect,
The developer scraping means is mainly characterized in that it is a developing device having a triangular prism-shaped cross section.

[0006]

According to the present invention, there is provided a developing device configured as described above.
In order to scrape back the developer, which returns from the axial end of the developer carrier to the paddle side and accumulates between the end of the paddle and the side plate of the developing container, in the direction away from the developer carrier. , From one end side of the paddle to the side plate side of the developing container by cooperation of the developer scraping means fixed to the end portion of the paddle and the developer regulating means fixed to the other end side of the means. Since the movement of the developer is regulated, even if the developer becomes bulky or deviated to the side plate side of the developing container and the end of the developer carrier, from the end of the developer carrier,
A large amount of developer near the edge of the paddle can be scraped away from the developer carrier in a short time, and the developer leaks or overflows, or the bearing locks due to developer intrusion. It is possible to provide a developing device with a low running cost by preventing the occurrence of the above, reducing the amount of the developer that does not contribute to the development, and reducing the used developer.

In the second aspect of the present invention, the developer regulating means is provided with a notch so that the developer can be moved from the side plate side of the developing container to the end portion side of the paddle. Even if the developer becomes bulky or uneven on the side plate side and the end of the developer carrier, the developer near the end of the paddle is removed from the developer carrier from the end of the developer carrier. A large amount of it is scraped out in a short time in the direction away from it, the amount of developer remaining near the side plate side of the developing container is also reduced, and the bearing locks due to developer leakage or overflow or developer intrusion. It is possible to provide a developing device with a low running cost by preventing the occurrence of such problems as described above, reducing the amount of the developer that does not contribute to development, and decreasing the amount of developer used.

According to a third aspect of the present invention, the developer regulating means is provided with a notch at a position downstream of the developer scraping means in the rotational direction of the developer regulating means so that the end of the paddle from the side plate side of the developing container. Since the developer can be moved to the part side, even if the developer becomes bulky or deviated between the side plate side of the developer container and the end of the developer carrier, the developer carrier The developer near the end of the paddle will be scraped out in a large amount in a short time in the direction away from the developer carrier, and the amount of developer remaining near the side plate of the developing container will be even greater. By reducing the amount of developer that does not contribute to the development, the amount of developer that does not contribute to development is reduced and the amount of developer used is also reduced. To provide a developing device with low running cost It can be so.

In the fourth aspect, since the developer scraping means is a columnar body having a circular cross-sectional shape, the bulkiness or deviation of the developer on the side plate side of the developing container and the end portion of the developer carrier may occur. Even in this case, a large amount of the developer near the end of the paddle will be scraped out from the end of the developer carrier in the diffusion direction away from the developer carrier, and the developer will not leak or overflow. Alternatively, it is possible to provide a developing device having a low running cost by preventing the occurrence of the lock of the bearing due to the invasion of the developer, the amount of the developer not contributing to the development is reduced, and the developer used is also reduced. To be able to.

According to the fifth aspect of the present invention, since the developer scraping means has a quadrangular prism shape in cross section, the bulk of the developer increases on the side plate side of the developing container and the end portion of the developer carrier. Even if it shifts to one side, the developer near the end of the paddle will be scraped out in a larger amount in the direction away from the developer carrier from the end of the developer carrier, and the developer will leak. It is possible to prevent the occurrence of bearing lock and the like due to overflow, or invasion of developer, reduce the amount of developer that does not contribute to development, and reduce the amount of developer used. To be able to provide.

According to the sixth aspect of the present invention, since the developer scraping means has a triangular cross-sectional shape, the bulk of the developer increases on the side plate side of the developing container and the end portion of the developer carrier. Even if it shifts to one side, the developer near the end of the paddle will be scraped out more in a short time in the desired non-tangential direction away from the developer carrier, from the end of the developer carrier. The device is compact because the layout restrictions are relaxed, and the leakage and overflow of the developer or the locking of the bearing due to the intrusion of the developer is prevented, and the amount of the developer that does not contribute to the development is also reduced. Therefore, it is possible to provide a developing device having a low running cost by using less developer.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a vertical cross-sectional view showing the structure of a developing device according to an embodiment of the present invention, FIG. 2 is a horizontal cross-sectional view of a main part thereof, and FIG. 3 is a front vertical cross-sectional view of FIG. In each of the drawings, in the developing device of the present invention, a magnet (2a) is disposed inside a developer (D) (for example, a two-component developer including toner and carrier) housed in a developing container 1 to rotate in the direction of arrow A in the figure. Development area (d) formed by the developer carrying member 2 (developing roller) that has been carried and formed between the developer carrying member 2 and the latent image carrying member 6.
The electrostatic latent image formed on the latent image carrier 6 is conveyed to the developing unit to develop a toner image. The developer (D) is supplied to the developer carrier 2 having the magnet 2a disposed therein while stirring by the rotation of the rotatably supported paddle 3 in the direction of arrow B. There is. By developing the electrostatic latent image formed on the latent image carrier 6, the toner concentration in the developer (D) decreases,
To compensate for this, the toner is replenished by the toner replenishing roller 7, and the developer (D) to which the toner has been replenished is mixed and agitated by the agitating roller 8 to maintain a predetermined toner concentration and obtain a developing quality. It is designed to be used.

The developer (D) after the development in which the toner concentration is reduced is the arrow C below the developing roller of the developer carrying member 2.
Then, the paddle 3 carries the toner to the mixing / stirring region by the stirring roller 8 to recover the proper toner concentration. The developer scraping means 4 is connected to the rotation shaft of the paddle 3.
The cross-sectional shape having a gap between them is a cylindrical rod shape, and one end 4a is fixed to the end 3a side of the paddle 3,
Is rotated in the direction of the arrow B, the axial end portion 3 of the paddle 3 is
The developer (D) located between a and the side plate 1a of the developing container 1 is scattered and scraped in the direction of arrow E. The developer regulating means 5 is provided on the other end 4b side of the developer scraping means 4 and regulates the movement of the developer (D) from the end portion 3a side of the paddle 3 to the side plate 1a side of the developing container 1. To do.

FIG. 4 is a diagram for explaining the operation of the paddles of FIGS. 2 and 3, in which developer (D) is applied on the side plate 1a side of the developing container 1 and on the axial end side of the developer carrier 2. Even if the paddle 3 becomes bulky or offset, the rotation of the paddle 3 in the direction of the arrow B causes the developer (D) in the vicinity of the end portion 3a of the paddle 3 from the end portion of the developer carrier 2 to be the developer regulating means. The restriction plate 5 regulates the movement toward the side plate 1a, and the developer scraping unit 4 scrapes a large amount of the developer in the direction normal to the upper side of the drawing and away from the developing roller of the developer carrier 2. Therefore, the accumulated developer can be greatly reduced in a short time as compared with the conventional developing device.
FIG. 5 is a front vertical cross-sectional view of a main part of a developing device according to a modified example of the present invention. The developer regulating means 5 has an outer peripheral edge portion from the side plate 1a side of the developing container 1 to the end portion 3a of the paddle 3. It has a notch 5a, which is notched to allow the developer (D) to move to the side. The notch portion 5a is provided at a position downstream of the developer scraping-out means 4 in the rotation direction B of the paddle 3. Therefore, the developer (D) near the side plate 1a of the developing container 1 moves from the side plate 1a side to the end 3a side through the notch portion 5a, so that it is easy to collect and the developer (D) near the side plate 1a of the developing container 1. It is possible to significantly reduce the developer (D) remaining in the above.

FIG. 6 is a vertical cross-sectional view of the main part of a developing device according to another embodiment of the present invention. Although the cross-sectional shape of the developer scraping means 4 in the above-mentioned embodiment is a cylindrical shape, in the present invention, Four
A prism-shaped developer scraping means 40 is used. For this reason, the developer can be reliably caught by the flat surface of the developer scraping unit 4 (not shown) having a cylindrical shape. As a result, a large amount of the developer (D) near the end 3a of the paddle 3 is scraped from the end of the developer carrying member 2 in the direction away from the developer carrying member 2, and the conventional developing device is used. Compared with, it is possible to further reduce the amount of the developer that tends to accumulate in a short time.

FIG. 7 shows another embodiment. The developing device of this embodiment has a columnar developer scraping means 40 having a triangular cross section.
a, and one of the bases of the triangle is arranged so as to face the rotation axis. According to the columnar developer scraping-out means 40a, the developer scraping-out means 40 having a rectangular prism shape is
The developer (D) in the vicinity of the end 3a of the paddle 3 is further scraped from the end of the developer carrier 2 in the direction away from the developing roller of the developer carrier 2, Even when compared with the developing device of No. 3, it is possible to further reduce the developer that tends to accumulate in a short time.

FIG. 8 is a constitutional view of yet another embodiment, in which the triangular prism-shaped developer scraping means 40a shown in FIG. 7 is rotated by a desired angle so that one of its bases faces the outer diameter direction. It is different from 7. As shown in the figure, the developer scraping means 40b in the shape of a regular triangular prism removes the developer (D) near the end 3a of the paddle 3 from the end of the developer carrier 2 to the developing roller of the developer carrier 2. Since a large amount can be scraped out in a desired non-tangential direction away from the device, the layout can be relaxed and the device can be made compact.

[0018]

As described above, according to the first aspect of the invention, the axial direction of the developer carrying member returns to the paddle,
In order to scrape out the developer accumulated between the axial end portion of the paddle and the side plate of the developing container in the direction away from the developer carrier,
One end side is provided at the other end of the developer scraping means provided at the end portion of the paddle, and a developer regulating means is provided so as to regulate the movement of the developer from the end portion side of the paddle to the side plate side of the developing container. Therefore, even if the developer becomes bulky or deviated to the side plate side of the developing container and the end of the developer carrier, the developer near the end of the paddle can be removed from the end of the developer carrier. It becomes possible to scrape out a large amount in a short time in the direction away from the developer carrier, prevent the developer from leaking or overflowing, or preventing the bearing from locking due to intrusion of the developer. Since the amount of the developer that does not contribute to the decrease in the amount of the developer used is also reduced, it is possible to provide a developing device having a low running cost.

According to the second aspect of the invention, the developer regulating means is provided with a notch so that the developer can be moved from the side plate side of the developing container to the end side of the paddle. , Even if the developer becomes bulky or deviated to the side plate side of the developing container and the end of the developer carrying member, the developer near the end of the paddle is removed from the end of the developer carrying member. A large amount can be scraped away from the carrier in a short time, the amount of developer remaining near the side plate side of the developing container also decreases, and due to developer leakage or overflow, or developer intrusion. Since it is possible to prevent the occurrence of locking of the bearing and reduce the amount of the developer that does not contribute to the development, it is possible to provide a developing device that uses less developer and has a lower running cost.

According to the third aspect of the present invention, the developer regulating means is provided with a notch provided at a position on the downstream side of the developer scraping means in the rotation direction of the developer regulating means so that the developer regulating means is provided with a side plate side of the developing container. Since the developer can be moved to the end of the paddle, even if the developer becomes bulky or offset on the side of the developer container and the end of the developer carrier, From the end of the agent carrier, remove the developer near the end of the paddle,
In the direction away from the developer carrying member, a large amount is scratched out in a short time, the amount of the developer remaining near the side plate side of the developing container becomes smaller, and the developer leaks or overflows, or
It has become possible to provide a developing device which prevents the occurrence of bearing lock and the like due to the invasion of the developer and reduces the amount of the developer that does not contribute to the development, thereby reducing the developer used and the running cost.

According to the fourth aspect of the present invention, since the developer scraping means has a cylindrical cross section, the bulkiness of the developer is increased or offset on the side plate side of the developer container and the end portion of the developer carrier. Even in this case, a large amount of the developer near the end of the paddle will be scraped out from the end of the developer carrier in the diffusion direction away from the developer carrier, and the developer will not leak or overflow. Alternatively, it is possible to provide a developing device which prevents the occurrence of the lock of the bearing due to the invasion of the developer and reduces the amount of the developer that does not contribute to the development so that the used developer is reduced and the running cost is low. Became.

According to the invention of claim 5, since the developer scraping means has a quadrangular cross-section, the developer becomes bulky or uneven on the side plate side of the developing container and the end portion of the developer carrier. Even if it does, the developer in the vicinity of the end of the paddle will be scraped out from the end of the developer carrier in a larger amount in a shorter time in the direction away from the developer carrier, and the developer will not leak. It is possible to provide a developing device which prevents the occurrence of overflow of the bearing or lock of the bearing due to the invasion of the developer and reduces the amount of the developer not contributing to the development, thereby reducing the used developer and the running cost. It became so.

According to the invention of claim 6, since the developer scraping means has a triangular prism-shaped cross section, the bulkiness of the developer is increased on the side plate side of the developer container and the end portion of the developer carrier, and the developer is biased. Also, from the end of the developer carrying member, the developer in the vicinity of the end of the paddle can be scraped out in a larger amount in a short time in a desired non-tangential direction away from the developer carrying member. The equipment is compact because the layout restrictions are relaxed, and the leakage and overflow of the developer or the lock of the bearing due to the invasion of the developer is prevented and the amount of the developer that does not contribute to the development is reduced. The amount of developer is reduced, and it is possible to provide a developing device with low running cost.

[Brief description of drawings]

FIG. 1 is an explanatory diagram illustrating an outline of a developing device according to an embodiment of the present invention.

FIG. 2 is a plan view illustrating a main part of the developing device according to the embodiment of the invention.

3 is a front vertical cross-sectional view of FIG.

FIG. 4 is a cross-sectional view for explaining the operation of the embodiment example shown in FIGS.

FIG. 5 is a front vertical sectional view illustrating a developing device according to another embodiment of the present invention.

FIG. 6 is a front view illustrating a main part of a developing device according to another embodiment of the present invention.

FIG. 7 is a front view illustrating a main part of a developing device according to another embodiment of the present invention.

FIG. 8 is a front view illustrating a main part of a developing device according to another embodiment of the present invention.

FIG. 9 is a plan view illustrating a main part of a conventional developing device.

FIG. 10 is an explanatory diagram illustrating a state of another main part of the conventional developing device.

FIG. 11 is an explanatory diagram illustrating a state of another main part of the conventional developing device.

FIG. 12 is an explanatory diagram illustrating a state of another main part of the conventional developing device.

[Explanation of symbols]

1 developer container, 1a side plate, 2 developer carrier, 2a
Magnet, 2b bearing, 3 paddle, 3a end, 3
b bearing, 4 developer scraping means, 4a one end, 4b
The other end, 5 developer regulating means, 5a notch, 6 latent image carrier, 7 toner replenishing roller, 8 stirring roller, 4
0 developer scraping means, 40a developer scraping means, 40b developer scraping means, 101 developing container,
101a side plate, 102 developing roller, 102a magnet, 102b bearing, 103 developer stirring pumping member, 103a end portion, 103b bearing, 104
fin

Claims (6)

(57) [Claims] 1. A developer container containing a developer, a paddle rotatably arranged in the developer container, and a developer supplied while being stirred by the rotation of the paddle, carried on a peripheral surface and conveyed to a developing area. And a developer carrying member for developing the electrostatic latent image formed on the latent image carrying member by the developer carried to the developing area by the developer carrying member. Has a rod shape with one end fixed to the side
With a structure having a gap between the paddle and the rotary shaft, the developer that has moved from the developer carrier and accumulated between the end of the paddle and the side plate of the developing container is separated from the developer carrier. And a developer restricting unit that is provided at the other end of the developer scraping unit and restricts the movement of the developer from the end portion side of the paddle to the side plate side of the developing container. Characteristic developing device. 2. The developing device according to claim 1, wherein the developer regulating means has a notch portion that allows the developer to move from the side plate side of the developing container to the end portion side of the paddle. A developing device characterized by the above. 3. The developing device according to claim 2, wherein the cutout portion is provided at a position downstream of the developer scraping unit in the rotation direction of the developer regulating unit. Development device. 4. The developing device according to claim 1, 2 or 3, wherein the developer scraping means has a cylindrical cross section. 5. The developing device according to claim 1, 2 or 3, wherein the developer scraping means has a quadrangular prism shape in cross section. 6. The developing device according to claim 1, 2 or 3, wherein the developer scraping means has a triangular prism-shaped cross section.