JPH04130969U - Dry two-component developing device and image forming device using the developing device - Google Patents

Abstract

(57) [Summary] [Purpose] To extend the life of the developer in a dry two-component developing device, substantially eliminating the need to replace the developer or obtaining stable images for a long period of time without replacing the developer. [Structure] The developer tank 70 is arranged at the back of the device set position of the black developer 50B, and a tank joint part 91 is provided at the bottom of the developer tank. A connectable main body joint portion 81 is provided. The developer taken in from the developer intake port 90 formed on the back side of the device on the separator 55 is transferred to the developer tank 7.
0, and the developer in the developer tank 70 is carried into the screw accommodating portion 55a and transported to the front side of the apparatus. As a result, the developer used in the black developing device 50B is also stored in the developer tank 70, increasing the total amount of developer and reducing developer fatigue.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

Dry two-component used in image forming devices such as copiers, facsimile machines, printers, etc. Regarding the developing device, in detail, it is possible to reduce the frequency of replacing the developer in the developing device. The present invention relates to an upcoming dry type two-component developing device and an image forming apparatus using the developing device. Ru.

0002

[Conventional technology]

When using a dry two-component developing device for a long period of time, the developer deteriorates and the image deteriorates. Since this has an adverse effect, it is necessary to replace the developer in the developing device as appropriate. this exchange This work involves disassembling the developing device and removing all the developer stored inside the device. It was a time-consuming task to put in new developer after taking it out. Therefore, in order to reduce the burden of replacing the developer, some of the work is automated. Some proposals have been made to dispose of used developer and to install new developer in equipment. Manual work such as loading remains, and it has not yet been possible to sufficiently reduce replacement work. not present.

0003

[Problem that the idea aims to solve]

This invention was created in view of the above problems, and its purpose is to: By extending the life of the developer in the dry two-component developing device, you can virtually eliminate developer replacement. It is possible to obtain stable images without having to replace or replace it for a long period of time. An object of the present invention is to provide a dry two-component developing device and an image forming apparatus using the developing device. Ru.

0004

[Means to solve the problem]

In order to achieve the above object, the present invention has developed a dry two-component developing device. a developer carrier that supplies the developer onto the developer and the image carrier; and a stirring member that stirs the developer. a developing device having; a developer storage container separate from the development device that stores developer; A developer circulation device that circulates developer between the developing device and the developer container is installed. It is characterized by a large number of characters.

[0005]

[Effect]

In this invention, the developing device is operated between the developer container and the developer container, which stores the developer separately from the developer device. Since the developer is circulated, the total amount of developer used in the developer is kept within the developer. The total amount of developer stored in the developer storage container and the developer stored in the developer storage container is Since the frequency of use of developer per developer is inversely proportional to the total amount, The frequency of use of developer per unit of developer in the developing device is reduced by the amount of developer that is being used. Reduced size to extend developer life, thereby increasing developer replacement intervals. It acts like a sea urchin.

[0006]

【Example】

An example will be described in which this invention is applied to an electrophotographic copying machine, which is an image forming apparatus. I will clarify. FIG. 1 is a schematic diagram of an electrophotographic copying machine according to an embodiment of the present invention. First, an overview of the entire copying machine will be explained. In FIG. 1, an original (not shown) on contact glass 1 is parallel to this. An optical system including an original irradiation lamp 2 that irradiates the original while moving to a uniform area. An image is formed on a drum-shaped photoreceptor 4, which is a latent image carrier, which has already been uniformly charged by an electric device 3. As a result, an electrostatic latent image is formed on the photoreceptor 4. This electrostatic latent image is A toner image is formed by toner from a developing device 5 provided on the right side of the light body. here , the developing device 5 is a developing device using a two-component developer. This toner image is The image is transferred onto the transfer paper conveyed from the device 6 by the transfer charger 7. Tona - The transfer paper on which the image has been transferred is separated from the photoreceptor 4 by the separation charger 8 and fixed. It passes through the printing device 9 and is discharged outside the machine as copy paper. On the other hand, the surface of the photoconductor 4 after the transfer is cleaned by a cleaning device installed on the left side of the photoconductor 4. The residual toner is removed by the step 10, and the toner is prepared for the next charging by the uniform charger 3. Ru.

[0007] Next, the developing device 5 of this embodiment will be described in detail. As shown in FIG. 1, the developing device in this example corresponds to the photosensitive drum 1 on the left side of the drawing. A developing device 50 is disposed facing the developing device 50, and a toner supplement attached to the upper right portion of the developing device 50. It is composed of a supply device 60 (see FIG. 1) and a developer tank 70. This developing device 50 is mounted together with a toner replenishing device 60 by a conventionally well-known support mechanism. is independently supported on the main body of the device in a detachable manner. And this In the example, a black developer 50B using black toner and a color developer 50B using color toner are used. The developing device 50C can be selectively set in the main body of the apparatus. In this example, we use a color developer. A conventionally known developing device shown in FIG. 2 is used. First, the color developing device 50C will be explained. In FIG. 2, the color developing device 50C includes an opening facing the surface of the photoreceptor drum. A developing roller 51 is provided along the bottom of the developer casing. Paddle 52 that supplies developer to the surface of this developing roller 51, toner supply in the upper right The toner that has just been replenished from the device 60 (see Figure 1) is fed into the developer and developed. A mixing roller 5 that mixes and stirs the developer and toner and supplies the developer to the paddle 52 side. 3 is provided. The paddle 52 and the mixing roller 53 each rotate around a central axis. It is rotated clockwise. On the upper part of the developing roller 51, there is a surface of the developing roller 51. A doctor 54 is provided to regulate the amount of developer carried and conveyed to the surface of the photoreceptor. There is. The developer regulated by the doctor 54 is placed on the paddle 52 on the right side of the doctor 54. A separator 55 is also provided for refluxing the water. This separator 55 has an internal cavity. A screw housing section equipped with a conveyance screw 26 for conveying the developer to the front of the device. 55a and extending from the right edge of the horizontal upper wall of the housing portion 55a to above the mixing roller 53. It consists of a downward slope section 55b. The cavity of the screw accommodating portion 55a is horizontal. A drug inlet 57 formed on the back side of the device on the upper wall and a drug outlet 58 at the front end of the device. It communicates with the inside of the developing unit. On the upper surface of the downward slope part 55b, there is a A fin 59 is provided to convey the image agent to the back side of the apparatus.

[0008] In the above configuration, during the developing operation, each rotating member 51, 52, 53, 5 in the developing device 6 is driven, and the mixing roller 53, paddle 52, developing roller 51, and doctor 54 are sequentially driven. The developer is transported by the doctor 54 onto the developing roller 51 and applied to the surface of the photoreceptor. The developer conveyed to the surface flows down on the downward slope portion 55b of the separator 55 and mixes with the developer. The developer is separated into the developer that is refluxed to the roller 53, and the developer that is refluxed to the mixing roller 53. The agents are mixed and stirred by the mixing roller 10 and supplied to the surface of the developing roller 51 again. child During the circulation of the agent, the agent is discharged from the agent inlet 57 on the upper wall of the screw accommodating portion 55a of the separator 55. The developer taken into the storage section 55a is transported to the front side of the apparatus by the transport screw 56. The agent is transported and discharged from the agent discharge port 58. In addition, the downstream inclined portion 55b of the separator 55 The developer flowing down is conveyed to the rear side of the apparatus by fins 59. These developing rows Lateral agitation of the developer due to the balance of conveyance of the developer in opposite directions in the axial direction will be carried out. The toner supplied from the toner supply device 60 into the developing device is It is fed into the developer near the mixing roller 53 and mixed and stirred with the developer.

[0009] Next, the black developing device 50B and the developer tank 70 will be explained. In the color developing device 50C, since the developer is stored only in the developing device 50C, The capacity of the developing device 50C was set to be relatively small due to constraints such as the layout within the device. In this case, the amount of developer that can be stored will be increased accordingly, and the amount of developer that can be used in the developing device 50C will be increased accordingly. The life of the developer, which is determined by the total amount of developer used, is also relatively short. comparison This is often sufficient for color developing device 50C, which is rarely used. However, in the frequently used black developing device 50B, if the developer life is short, the developer The replacement interval becomes shorter and the maintenance burden increases. Therefore, in this embodiment, the developer used in the black developer 50B is A developer tank 70 separate from the developer tank 50B is also stored, and the developer tank 50B and the developer tank The developer is circulated between the developer unit 50B and the developer unit 50B. The amount is increased by the capacity of the developer tank 70 to extend the life of the developer. be.

0010 The black developing device 50B has a developing roller 51 and a pattern like the color developing device 50C described above. It includes a dollar 52, a mixing roller 53, and a separator 55. Of these, sepa The structure of the developer 55 is different from that of the color developer 50C. That is, the separator 55 of the color developing device 50B has the conveying screw 5 in the internal cavity. In order to take the developer into the storage section 55a that accommodates 6, the horizontal top of the storage section 55a Whereas the agent inlet 57 is formed in the wall, in the black developing device 50B, instead of this, As shown in FIGS. 3 and 4, there is a A drug intake port 90 communicating with the drug delivery chamber 83 of the main body joint portion 81 is connected to the downward slope portion 55. It is formed on the back side of the device in b.

[0011] Then, as shown in FIG. 3, the developer tank 70 is installed in the device set of the black developer 50B. The developer tank is located at the back of the While the tank joint part 91 is provided at the bottom of the black developer unit, as shown in FIG. A main body joint part 81 connectable to the tank joint part 91 is also provided on the wall 80. Ru.

0012 The main body joint portion 81 on the black developer side is internally divided into left and right sides by a partition wall 83. It communicates with the conveyance screw accommodating section 55a in the developing device, and is connected to one of the conveyance screws 56. The agent intake chamber 82 has an extending end, and the downwardly inclined portion 55 of the separator 55 in the developing device. A drug discharge chamber 83 is formed which communicates with the drug intake port 90 formed on the back side of the device in b. ing. The upper wall of the agent intake chamber 82 is provided with a agent that receives the agent from the developer tank 70 side. An intake port 82a is formed. The developer tank 70 side is located on the bottom wall of the developer discharge chamber 83. A agent discharge port 83a is formed for conveying the agent to the developer, and the agent on the downward slope portion 55b in the developing device is formed. The bottom wall 83b of the communication path from the intake port 90 to the agent outlet 83a is formed to be inclined. ing. Main body joint in which the agent inlet 82a and agent outlet 83a are formed A compression spring 85 is attached to the side surface of the portion 81 so that the portion 81 is always moved away from the rear side wall 80 of the developing device. A biased separator shutter 86 is slidably attached. The width of the separator shutter 86 in the sliding direction is determined by the compression spring 85. The agent intake port 82 is pushed out until it is stopped by a stopper mechanism (not shown). 83a and the agent outlet 83a. And the separates On the left and right sides of the data shutter 86, there are tank joint parts of a developer tank 70, which will be described later. The guide protrusion 86a guided by the guide groove (see FIG. 3) formed in the It is formed.

[0013] The tank joint portion 91 of the developer tank 70 is connected to the main body joint of the black developer 50B. It has a shape that allows the joint part 81 to fit into it, and the guide protrusion of the main body joint part 81. Guide grooves 92 for guiding the portion 86a are formed on the left and right inner surfaces, respectively. When connected to the main body joint part 81 as shown in FIG. 5(a), the main body joint part 81 The front side of the developer tank 70 is located on the upper wall of the inlet portion 81 in a portion facing the developer intake port 82a. A developer drop port 94 whose wall partially protrudes so that the developer in the developer tank 70 can flow down. is formed. This developer flow outlet 94 has one end connected to the bottom of the developer tank 70. A tank shutter that is always biased toward the front of the device by a tension spring 95 that is fixed to the wall. 96 (see FIG. 6(a)). Also, as shown in FIG. 5(b), when connected to the main body joint part 81, the main body A developer tank 70 is provided in a portion of the lower wall of the joint portion 81 that faces the agent outlet 83a. A drug drop port 93 to a drug transport pipe 98 to a drug inlet port 97 formed at the top of the front side wall of the It is formed. The developer in the tube is conveyed upward into the developer conveying tube 98, and the developer is conveyed upward. A conveyance screw for carrying the agent into the main body of the developer tank 70 from the carry-in port 97 99 is provided.

[0014] In the above configuration, in the black developing device 50B, basically the above-mentioned color In the same manner as the developing device 50C, the developer is supplied to the developing roller 51 and the development inside the developing device is carried out. The developer is stirred. The difference is that there is a shape on the back side of the developing device on the separator 55. The developer taken in from the developer intake port (57, 90) is conveyed in the axial direction of the developing roller. When carrying out the agent from the developer outlet 58 on the front side of the developing device, the color developing device 50C In this case, instead of carrying out the conveyance only through the screw accommodating part 55a, The developer 50B output conveys the developer taken in from the developer intake port 90 to the developer tank 70. Then, the developer in the developer tank 70 is transported to the screw storage section 55a and the developer is transported. The point is that they are sending That is, as shown in FIG. 5(b), the development from the agent inlet 90 on the separator 55 The developer is delivered to the developer outlet chamber 83, developer outlet 83a, and developer tank of the main body joint part 81. Pass through the agent drop port 93 on the bottom wall of the tank joint part 91 of the tank 70 and enter the agent transport pipe 98. The conveying screw 99 in the pipe 98 transports the developer to the upper developer tank 70. The agent is carried into the container through the agent inlet 97, which is the inlet of the agent. On the other hand, as shown in Fig. 5(a) As shown in FIG. through the agent drop port 94 and the agent intake port 82a on the upper wall of the main body joint part 81. The agent reaches the agent intake chamber 82 of the inlet section 81, and the liquid inside the developing device 50B is moved by the conveying screw 56. The agent passes through the screw accommodating portion 55a and is discharged from the agent discharge port 58. Note that the amount of developer transported from the black developing device 50B to the developer tank 70 is the opposite. The amounts of developer transported from the developer tank 70 into the developing device 50B are not the same. As a result, the amount of developer in the developing device 50B increases or decreases, and the developer becomes unable to circulate. , to avoid problems such as agent leakage into the device, make sure that these amounts are the same. The capacity of each conveying screw 56, 99 is set so that

[0015] Next, the operation when the black developing device 50B is attached to and detached from the main body of the apparatus will be explained. When taking out the black developing device 50B from the main body of the apparatus, remove the black developing device 50B from the developing roller. Pull it out toward the front of the device in the 51-axis direction. At this time, the developer tank 70 is Since it remains in the fixed position, the main body joint part 8 as shown in Figures (a) and (b) 1 and the tank joint part 91 are separated. Both joint parts 81 are separator shutters. The shutter 86 is pushed relatively to the right by the biasing force of the compression spring 85, and the book is Covering the agent inlet 82a on the upper wall of the body joint part 81 and the agent outlet 83a on the bottom wall, This prevents developer from spilling from the developer intake port 82a etc. when the black developer 50B is handled. Can prevent scattering. On the other hand, in the tank joint portion 91, the tank shutter 96 is closed. It is pulled relatively to the left side by the tension spring 95 and covers the drug flow outlet 94. This makes it possible to prevent leakage of developer within the device.

[0016] When setting the black developing device 50B in the apparatus main body, reverse the above operation and insert it into the apparatus main body. With the insertion of the developing device 50B, the separator shutter 86 of the main body joint portion 81 is opened. The biasing force of the compression spring 86 hits the front end of the tank joint part 91. The drug inlet port 82a and the drug outlet port 83a are opened by moving relatively to the left side against the To go. On the other hand, the tank shutter 95 of the tank joint part 91 is connected to the main body joint. 81 and against the biasing force of the tension spring 95. The user then moves to the right side and opens the agent drop port 94. And the black developer 50B When the setting is completed, the state will be as shown in FIGS. 5(a) and 5(b).

[0017] Note that when attaching and detaching the color developing device 50C to the main body of the apparatus, the tank joint portion 91 has been evacuated from the set space of the color developing device 50C, so the color developing device 50C The presence of the developer tank 70 does not interfere with the attachment and detachment of C. Furthermore, different types The color developer 50C, which uses a color developer that is a dry type developer, has a main body. Since the joint part 81 is not provided, the black developer in the developer tank 70 is colored. It does not get mixed into the developing device 50C.

[0018] In the above embodiment, the developer is transported from the black developing device 50B to the developer tank 70. It is integrated into the developer tank and the developer discharge chamber 83 of the main body joint part 81, which is a feeding path. Develop the developer transport pipe 98 from the developer tank 70 to the front side of the black developer 50B. A conventional developer is already equipped as part of the developer transport path that transports the developer. The conveying screw 56 inside the separator 55, which is a stirring means inside the developing device, is used. As a result, the developer can be easily installed without major changes in the layout within the conventional developer. A developer circulation path between 50B and the developer tank 70 could be constructed.

[0019]

[Effect of the idea]

According to the invention of claim 1, there is provided a developer storage container that stores developer separately from the developer and a developer. Since the developer is circulated between the developing device and the developing device, the total amount of developer used in the developing device is The total amount of developer contained in the container and the developer contained in the developer container. Since the frequency of developer use per unit developer is inversely proportional to the total amount, the developer The amount of developer per unit of the developing device is equal to the amount of developer stored in the container. Extend the life of the developer by using it less frequently, which reduces the interval between developer replacements. Because it can be made longer, it virtually eliminates the need to replace the developer or allows long-term replacement. This has the excellent effect of being able to obtain stable images without having to change the image. example For example, if the amount of developer stored in the developer container is the same as that of the developer, the lifespan of the developer will be The lifespan can be doubled compared to conventional equipment that does not use a developer container, and the capacity of the developer container can be doubled. If it is twice that of the developing device, the life of the developer can be tripled compared to the same conventional device. I can do it. Further, according to the invention of claim 2, in the dry two-component developing device of claim 1, the above-mentioned A developer circulation device includes a first developer transport path from the developing device to the developer container. , a second developer transport path from the developer container to the developing device; The developer intake part on the developing device side of the first developer transport path is connected to the developer inlet in the developing device. disposed on one end side of the developer carrier in the axial direction, and on the developing device side of the second developer conveyance path. The agent discharging section is arranged at the other end in the axial direction of the developer carrier in the developing device. Therefore, the developer circulating device described above can be used to horizontally stir the developer in the developing device. I can do that. Furthermore, according to the invention of claim 3, the developing device of the dry two-component developing device of claim 1 is installed. In an image forming apparatus that is removably installed in a device main body, the developer circulation device is connected to the developer circulation device. Since the imager side and the device main body side are configured to be separable, the above developer circulation device A member on the developing device side is provided integrally with the developing device, so that the developing device can be removed from the main body of the apparatus. In conjunction with the loading operation, the developer circulation device is separated and connected to the developer side and the device main body side. It is possible to perform continuous operations. Further, according to the invention of claim 4, in the image forming apparatus of claim 3, the separable The configuration of the device main body side of the developer circulation device that is configured to be able to handle other types of developer and a developer carrier that supplies developer to the image carrier, and the developer circulation device The developing device that is not equipped with the above-mentioned developing device side mechanism can be freely attached to and removed from the main body of the device. , installed outside the mounting space of the developing device, or installed so that it can be retracted outside the space. Since the developing device is attached to the main body of the device, even when performing developing operation, There is no circulation of developer between the container and the developer container, and the type of developer is It is possible to prevent abnormal images from being generated due to mixing of different developers.

[Brief explanation of drawings]

FIG. 1 is a front view showing a schematic configuration of an electrophotographic copying machine according to an embodiment.

FIG. 2 is a perspective view showing a schematic configuration of a color developing device used in the copying machine.

FIG. 3 is a perspective view showing a schematic configuration of a black developing device and a developer tank used in the copying machine.

FIG. 4 is a perspective view of the black developing device seen from the rear side of the copying machine.

FIG. 5 is a cross-sectional view for explaining the relationship of joint parts when the black developing device is set in a copying machine;
(a) is a cross-sectional view in a vertical plane passing through the agent intake chamber of the main body joint and parallel to the developing roller axis; (b) is a cross-sectional view in a vertical plane passing through the agent discharge chamber of the main body joint and parallel to the developing roller axis. figure.

FIG. 6 is a cross-sectional view illustrating the relationship between the joint parts when the black developing device is removed from the copying machine;
(a) is a cross-sectional view in a vertical plane passing through the agent intake chamber of the main body joint and parallel to the developing roller axis; (b) is a cross-sectional view in a vertical plane passing through the agent discharge chamber of the main body joint and parallel to the developing roller axis. figure.

FIG. 7 is a sectional view taken along a vertical plane passing through the axis of the conveying screw of the developer tank and parallel to the developing roller axis.

[Explanation of symbols]

50C Color developer, 50B Black developer 51 Developing roller, 52 Paddle 53 Mixing roller, 55 Separator 56 Conveying screw, 57,90
Agent intake port 58 Agent discharge port, 70 Developer tank 81 Body joint portion, 82a Agent intake port 83a Agent discharge port, 86 Separator shutter 91 Tank joint portion, 94 Agent drop port 96 Tank shutter, 98 Agent conveyance pipe 99 Conveyance screw

Claims (4)

[Scope of utility model registration request] Claims: 1. A developing device comprising a developer, a developer carrier that supplies the developer onto the image carrier, and a stirring member that stirs the developer; and a developer that is separate from the developer that accommodates the developer. A dry two-component developing device comprising: a developer container; and a developer circulation device that circulates developer between the developer container and the developer container. 2. The developer circulation device includes a first developer transport path from the developing device to the developer container and a second developer transport path from the developer container to the developing device. A developer intake portion on the developing device side of the first developer transport path is disposed on one end side in the axial direction of the developer carrier in the development device, and the developer intake portion of the second developer transport path Claim 1, characterized in that the agent discharge section on the side of the developing device is disposed at the other end in the axial direction of the developer carrier in the developing device.
dry two-component developing device. 3. An image forming apparatus in which the developing device of the dry two-component developing device according to claim 1 is removably attached to the device main body, wherein the developer circulation device is separated between the developing device side and the device main body side. An image forming apparatus characterized in that it is configured to enable 4. The image forming apparatus according to claim 3, wherein the structure of the separably configured developer circulating device on the apparatus main body side is adapted to supply another type of developer and the developer to the image carrier. A developing device having a developer carrying member and not having a mechanism on the developing device side of the developer circulation device is provided outside the mounting space of the developing device so that the developing device can be freely attached to and detached from the main body of the device. 4. The image forming apparatus according to claim 3, wherein the image forming apparatus is mounted or mounted so as to be retractable outside the space.