JP2002040805A - Developer replenishing and recovering device, developing device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make maintainability high and to obtain a stable image over a long term with simple and inexpensive constitution. SOLUTION: A developer cartridge 5 integrally equipped with a supplied developer storing part 5a storing developer to be supplied to a developing container 2 and a recovered developer storing part 5b storing recovered developer recovered from the container 2 is arranged nearly above the container 2. A magnet 7 rotatable centering a shaft 7a is arranged in the vicinity of the recovery port 6b of the storing part 5b, and the developer adhering to the magnet 7 is carried to the vicinity of the recovery port 6b by the rotation of the magnet 7, peeled by a scraper 8 and recovered into the storing part 5b from the recovery port 6b. The recovered amount of the developer is changed in accordance with toner concentration by a toner concentration detecting device 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic or electrostatic recording type image forming apparatus such as a copying machine or a printer, a developing device, and a developer supply and recovery device.

[0002]

2. Description of the Related Art In a conventional electrophotographic image forming apparatus, particularly an image forming apparatus for forming a chromatic image, a two-component developing method in which a non-magnetic toner and a magnetic carrier are mixed and used as a developer is used. Widely used. The two-component developing method has advantages such as stability of image quality and durability of the apparatus as compared with other developing methods currently proposed, but also deteriorates the developer due to long-term use, particularly, carrier. Since the deterioration of the developer is inevitable, it is necessary to replace the developer with the long-term use of the image forming apparatus.

Several solutions to this problem have been proposed in the past. For example, according to Japanese Patent Publication No. 2-21591, in a developing apparatus for an electrophotographic copying machine having a means for stirring a carrier and a toner, and a developing roll for supplying a developer stirred by the stirring means to a photoreceptor, A carrier replenishing device and a toner replenishing device are separately or integrally provided above the stirring means, and a developer overflow portion is provided on a side wall of the developing device housing, so that a new developer is replenished little by little by the replenishing device. The developer can be discharged from the overflow portion, and the characteristics of the developer in the developing device housing can be kept constant. As a result, the image quality of the copy can be kept constant. Further, since the old developer in the developing housing is automatically and automatically discharged from the developer overflow portion, the developing device is removed from the copying machine as in the conventional device, and the old developing device in the housing of the developing device is removed. After the developer is taken out and refilled with a new developer, a troublesome replacement operation of the developer such as mounting the developing device again becomes unnecessary, and the developer is prevented from being scattered.

That is, by gradually replacing the deteriorated developer (carrier) with a new one, the apparent deterioration of the carrier stops, and the characteristics of the developer as a whole are stabilized. This eliminates the need to replace the developer and improves maintainability.

[0005]

On the other hand, in recent years, as the market for full-color copying machines and printers has expanded and various functions have been required, for example, a plurality of photosensitive drums have been arranged to provide high productivity. Many tandem-type image forming apparatuses that perform multiple transfer have been commercialized and are expected to become one of the mainstream markets in the future.

However, in the tandem type image forming apparatus, the developing devices for each color are fixedly arranged for each photosensitive drum, and the simple structure proposed in Japanese Patent Application Laid-Open No. 9-218575, ie, It is possible to use a structure in which the developing device is mounted on a rotating body, a developer cartridge is exchangeably mounted on each developing device, and the developer is collected by using a change in the direction of action of gravity due to the rotation of the rotating body. Can not.

Therefore, in order to adopt a system in which the developer is gradually replaced in the tandem system, Japanese Patent Application Laid-Open No.
JP-A-630774 discloses a complicated configuration, that is, a toner replenishing device that replenishes toner in accordance with the consumption of toner in the developing container, a toner consumption detecting unit that detects the amount of toner consumed in the developing container, Carrier replenishing device for replenishing carriers according to the detected toner consumption amount, collecting container for collecting discharged developer, developer discharging device for maintaining the amount of developer in the developing container at a predetermined value, and operations thereof A complicated configuration having a controller and the like for controlling the

The same applies to an image forming apparatus for forming a monochromatic image and other configurations in which the developing device does not rotate.

That is, in the prior art, in a single-color image forming apparatus or a full-color image forming apparatus using a tandem system or the like that produces high productivity, the developer is gradually and automatically replaced to improve maintainability. If this is the case, on the contrary, the configuration becomes complicated, leading to an increase in the cost of the main body.

[0010] From the viewpoint of high stability of image quality, especially, stability of image density is also important. Therefore, a control method of changing the toner concentration of the two-component developer in the developing device has been generally used so that the patch image density on the photosensitive drum is kept constant during the durability. When such control is performed, the surface position of the two-component developer in the developing device changes with a change in the toner concentration.
That is, as the toner concentration increases, the surface position increases, and as the toner concentration decreases, the surface position decreases.

In such a state, Japanese Patent Publication No. Hei 2-21591
As disclosed in Japanese Patent Application Laid-Open Publication No. H10-260, when a developer overflow portion is provided on the side wall of the developing device and the developer is recovered by discharging the developer from the developer overflow portion, the surface position of the developer is kept constant. However, the amount of magnetic carrier in the developer changes depending on the toner concentration at that time. That is, when the toner concentration is high, the carrier amount decreases, and when the toner concentration is low, the carrier amount increases. For this reason, when the amount of the carrier increases, the torque becomes excessive, and when the amount of the carrier decreases, the agitation property of the replenishment toner becomes unstable, and problems such as image unevenness may occur.

Accordingly, an object of the present invention is to provide a developer replenishing and collecting apparatus, a developing apparatus, and an image forming apparatus capable of achieving high maintainability with a simple and low-cost configuration, and capable of obtaining a stable image for a long period of time. It is to provide.

[0013]

The above object is achieved by a developer supply / recovery device, a developing device, and an image forming apparatus according to the present invention. In summary, the present invention provides a developing container containing a two-component developer containing a toner and a magnetic carrier for developing an electrostatic latent image formed on an image carrier, and a toner concentration of the two-component developer. In a developer supply and recovery device of a developing device having a toner concentration detecting means for detecting
A replenishing developer container that contains at least toner and a replenishing developer to be replenished in the developing container; and a collecting port for collecting the two-component developer in the developing container. A collecting developer container integrally formed with the replenishment developer collecting unit for storing the collected collecting developer, and a two-component developing unit disposed in the vicinity of the collecting port and in or near the developing container. A magnetic field generating means which is rotatable about an axis for adhering an agent and conveyed to the recovery port, and is provided so as to be close to or in contact with the magnetic field generating means, and peels off the two-component developer attached to the magnetic field generating means. A developer replenishing and collecting device disposed substantially above the developing container.

According to another aspect of the present invention, there is provided a developing container containing a two-component developer containing a toner and a magnetic carrier for developing an electrostatic latent image formed on an image carrier, and the two-component developer. And a toner concentration detecting means for detecting the toner concentration of the developer, the developer supply and collection container disposed substantially above the developing container, and the developer supply and collection container stores at least the toner. And a recovery port for recovering the two-component developer in the developer container, and a recovery port recovered from the recovery port. A recovery developer storage unit formed integrally with the replenishment developer recovery unit for storing a developer, and a two-component developer in the development container or in the vicinity of the development container is disposed near the recovery port, And the collection port Magnetic field generating means rotatable about the axis of the conveying shaft, and a peeling member provided so as to be close to or in contact with the magnetic field generating means for peeling the two-component developer adhered to the magnetic field generating means. A developing device is provided.

According to another aspect of the present invention, an image carrier on which an electrostatic latent image is formed and a two-component developer containing a toner and a magnetic carrier for developing the electrostatic latent image are housed. An image forming apparatus comprising: a developing container; and a developing device having a toner concentration detecting unit for detecting a toner concentration of the two-component developer, further comprising a developer supply / recovery container disposed substantially above the developing container. The developer supply and recovery container contains at least toner, a supply developer storage unit that stores a supply developer to be supplied into the developer container,
A recovery port provided with a recovery port for recovering the two-component developer in the developing container, and configured to be integrated with the replenishment developer accommodating portion for storing the recovery developer recovered from the recovery port; A housing portion, a magnetic field generating means disposed near the collection port, for attaching a two-component developer in or near the developing container, and rotatable about an axis for conveying to the collection port;
Provided to approach or contact the magnetic field generating means,
An image forming apparatus, comprising: a separating member for separating the two-component developer attached to the magnetic field generating means.

According to one embodiment of the present invention, the image carrier is an endless belt-shaped photoconductor rotatably provided, and a plurality of the developing devices arranged in a substantially horizontal direction;
A plurality of developer replenishment collection containers for collecting the component developer, and the endless belt-shaped photoreceptor is arranged above the plurality of developing devices arranged in the substantially horizontal direction, The plurality of developer supply / collection containers are arranged inside a rotation path of the endless belt-shaped photoconductor.

According to another embodiment of the present invention, there are provided a plurality of image forming stations including at least the image carrier and the developing device, and a plurality of the developer supply / collection containers for collecting a two-component developer. An endless belt-shaped transfer member rotatably provided for carrying and conveying the toner image transferred from the image carrier, and the plurality of image forming stations are arranged in a substantially horizontal direction, The endless belt-shaped transfer member is disposed above the transfer member, and the developer supply / recovery container is disposed inside a rotation path of the transfer member.

According to an embodiment of the present invention, the amount of the two-component developer attached to the magnetic field generating means and conveyed to the collected developer accommodating section is detected by the toner concentration detecting means. It is preferable to change according to the concentration.

According to another embodiment of each of the above inventions,
The toner density detecting means detects the toner density by detecting the amount of received light using a light emitting unit and a light receiving unit disposed on the back side of the light transmissive detection window.

According to another embodiment of the invention, the toner concentration detecting means detects the toner concentration by detecting the magnetic permeability of the magnetic carrier in the two-component developer.

According to another embodiment of the invention, the amount of the two-component developer recovered is changed by changing the amount of rotation of the magnetic field generating means.

Further, according to another embodiment of the present invention, the peeling member is a single member or a part of the recovery port.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a developer replenishing and collecting apparatus, a developing apparatus, and an image forming apparatus according to the present invention will be described in more detail with reference to the drawings.

Embodiment 1 A first embodiment of the present invention will be described with reference to FIGS.

The operation of the image forming apparatus according to the present embodiment will be described with reference to FIG. First, an electrostatic latent image is formed on the photosensitive drum 28 by exposing the surface of the photosensitive drum 28, which is an image carrier, which is uniformly charged by the charger 21, by the laser 22, and the latent image is developed by the developing device 1. Thus, a toner image is formed on the photosensitive drum 28.

After this toner image is transferred to the recording paper 27 conveyed by the transfer belt 24 by the transfer bias by the transfer charger 23, the recording paper 27 is transferred to the transfer belt 2
4 and is conveyed to the fixing device 25 where it is pressurized and
Heated to obtain a permanent image. Further, the residual toner remaining on the photosensitive drum 28 after the transfer is removed by the cleaner 26 to prepare for the next image formation.

The developing device 1 will be described in detail. The developing device 1 contains a two-component developer composed of a non-magnetic toner and a magnetic carrier, and the toner concentration in the developer in an initial state is 7%. This value should be properly adjusted according to the charge amount of the toner, the carrier particle size, the configuration of the image forming apparatus, and the like, and does not necessarily have to follow this value.

The developing unit 1 has an opening in a developing region facing the photosensitive drum 28, and the developing sleeve 3 is rotatably arranged so as to be partially exposed at the opening. The developing sleeve 3 rotates in the direction of the arrow in FIG.
The two-component developer in the developing container 2 is held in a layered state, and is carried and conveyed to a developing area facing the photosensitive drum 28 to develop the electrostatic latent image. The developer after developing the electrostatic latent image is transported according to the rotation of the developing sleeve 3 and is collected in the developing container 2.

In the vicinity of the developing sleeve 3, a toner density detecting device (toner density detecting means) 10 is provided. In this embodiment, a method of detecting the toner density by detecting the amount of reflected light from the two-component developer using a light emitting unit and a light receiving unit disposed on the back side of the light transmissive detection window is used. However, the method is not particularly limited to this method, and for example, a method (inductance method) of detecting the toner concentration from the magnetic permeability of the magnetic carrier in the developer may be used.

A patch detection sensor 1 is provided near the photosensitive drum 28 on the downstream side of the developing device 1 in the rotation direction of the photosensitive drum 28.
1 is installed. The patch detection sensor 11 detects the density of the patch image developed on the photosensitive drum 28, and maintains the density of the patch image constant.
The toner concentration of the two-component developer in the developing device 1 is controlled.

A developer cartridge 5 for storing the developer to be supplied to the developing device 1 and for storing the old developer collected from the developing device 1 is provided substantially above the developing device 1. It is arranged so that it can be easily attached and detached.

The mixing ratio of the toner and the carrier of the replenishment developer contained in the developer cartridge 5 is about 9: 1 by weight, but is not particularly limited to this value. That is, the amount of toner in the developer cartridge 5 is overwhelmingly larger than the ratio of the two-component developer in the developing container 2, and considering the volume ratio, it is considered that a small amount of carrier is mixed in the toner. Can also. That is, when supplementing the toner consumed by image formation, a small amount of carrier is gradually supplied. If the ratio of the carrier of the developer to be replenished is increased, the replacement amount of the carrier is increased by the same amount of toner replenishment, and the two-component developer in the developing device 1 approaches a fresh state, but the consumed amount of the carrier is correspondingly Increase. For this reason, it is preferable to determine an appropriate mixing ratio in each device separately.

Next, a method of recovering the developer, which is a feature of the present invention, will be described with reference to FIGS.

As shown in FIG. 2, the developer cartridge 5 is formed in a substantially cylindrical shape as a whole, and has a replenishment developer container 5a.
And a collected developer container 5b. The replenishment developer contained in the replenishment developer accommodating portion 5a is transported by rotation of a developer replenishment screw 4 attached to the developing container 2. The rotation of the developer supply screw 4 is controlled by a developer supply amount control device (not shown), and an appropriate amount of the developer is conveyed and supplied to the developing device 1.

As shown in FIG. 3, a magnet 7 serving as a substantially disk-shaped magnetic field generating means is provided above the developing container 2. In FIG. 3, the magnet 7 is magnetized to the N-pole on the near side and the S-pole on the back side. The driving means (not shown) is separate from the driving means for the developer supply screw 4 in the arrow direction (counterclockwise) in FIG. Rotate.

The shape and magnetization pattern of the magnet 7 are not limited to those shown in the present embodiment. For example, the shape may be not only a polygon but also a rod. If the magnet 7 is not circular, a circle drawn by rotating a non-circular magnet may be used instead of the circular magnet 7 shown in this embodiment and the like. Also, the magnetization pattern may be configured such that N and S poles are alternately arranged on the circumference.

The magnet 7 is located in the vicinity of the inner side of the inside of the developing container 2 as shown in FIG.
Is close to the surface position of the two-component developer stored in the developing container 2 on the left side, and an appropriate amount of the developer is attached by magnetic force. The developer attached to the magnet 7 is collected near the collection port 6b of the collection developer accommodating portion 5b with the rotation of the magnet 7 about the shaft 7a. As shown in FIG. 3, the recovery port 6b is provided with an appropriate clearance from the magnet 7, and a scraper 8 as a peeling member made of urethane rubber is provided near the left of the recovery port 6b in FIG. , Is close to the right side of the magnet 7 in FIG. The developer conveyed by the rotation of the magnet 7 is collected at the collecting port 6b.
3 and is scraped off by the scraper 8 on the left side, and is gradually collected into the collection developer accommodating portion 5b.

In this embodiment, a single member is provided as the scraper 8 to improve the scraping property of the collected developer. However, in the present invention, the performance of the scraping member, which is a peeling member for the magnet 7, is improved. It is sufficient that the scraping member is kept to some extent, and a simpler configuration can be obtained by forming the scraping member using a part of the recovery port 5b.

Next, a method for controlling the amount of the collected developer will be described. FIG. 4 shows the configuration of the developing device according to the present embodiment.
This shows the proper surface position of the two-component developer used in the present embodiment. When the toner density is 7%, the position of B and the toner density are 5
%, The position is C, and when the toner density is 9%, the position is A. The proper surface position is a level at which the amount of magnetic carriers in the two-component developer in the developing container 2 becomes constant.

In this embodiment, the amount of rotation of the magnet 7 is appropriately changed according to the value detected by the toner concentration detecting device 10 of the developing device 1 so as to maintain the toner concentration and the surface position of the developer as described above. Specifically, when the toner density increases, the rotation amount is decreased, and when the toner concentration decreases, the rotation amount is increased. The method of changing the rotation amount of the magnet 7 can be easily performed by controlling the current of a DC motor (not shown) that is a driving source for rotating the magnet 7.

When removing the developer cartridge 5,
First, the developer cartridge 5 is rotated leftward in FIG. As a result, the collection port 6b is sealed by the shutter member 9, so that the contents of the collection developer container 5b do not leak. At this time, although not described in detail, the developer cartridge 5 supplies the replenishment developer from the replenishment developer accommodating portion 5b to the developer replenishment screw 4 as a replenishing port 6a.
Are similarly sealed by the shutter member 9. In this state, the developer cartridge 5 can be easily removed from the image forming apparatus main body by pulling the developer cartridge 5 toward the near side in FIG. When the developer cartridge 5 is mounted, the reverse operation may be performed.

In the single-color image forming apparatus having the above-described structure, the developer can be automatically changed gradually to achieve high maintainability, and a long-term stable image can be realized with a simple and low-cost structure. .

Embodiment 2 Next, a second embodiment of the present invention will be described with reference to FIGS. In the following description, members having the same reference numerals as those in the first embodiment with the suffixes of Y, M, C, and K are members for forming yellow, magenta, cyan, and black images, respectively. . For example, if the developing device 1 is described, the developing devices 1Y, 1M, 1C, 1
It shall refer to matters common to K.

In FIG. 5, the surface of a photosensitive belt 28 B, which is an endless belt-like photosensitive member charged by the charger 21, is exposed by the LED 22 so that the photosensitive belt 28 is exposed.
An electrostatic latent image is formed on B. The electrostatic latent image is first developed by driving the developing device 1Y to obtain a yellow toner image.

On the other hand, the recording paper 27 is conveyed from the paper supply cassette 29 in the direction of arrow A by a paper supply device (not shown), and is attracted onto the transfer drum 24 by a suction means (not shown). The toner image forming timing and the supply timing of the recording paper 27 are appropriately adjusted, and the toner image on the photosensitive belt 28B is transferred to the recording paper 27 on the transfer drum 24 by the transfer bias by the transfer charger 23. The residual toner remaining on the photosensitive belt 28B after the transfer is removed by the cleaner 26.

Next, the photosensitive belt 28B is charged again, exposed by the LED 22, and the formed electrostatic latent image is developed by driving the developing unit 1M to obtain a magenta toner image. The magenta toner image is transferred to the transfer drum 2 on which the yellow toner image is first transferred and rotates in the direction of arrow B.
4 and is transferred onto the recording paper 27 conveyed to the vicinity of the transfer charger 23 while being adsorbed on the recording paper 27.

Similarly, the latent image on the photosensitive belt 28B is developed by the developing unit 1C and the developing unit 1K to form a yellow, magenta, cyan and black toner image on the recording paper 27. The recording paper 27 onto which the toner images for the four colors have been transferred is peeled off from the transfer drum 24, conveyed in the direction of arrow C, and is pressed and heated by the fixing device 25 to obtain a permanent image.

The developing units 1 and the developer cartridges 5 for the respective colors have the same construction as in the first embodiment.

As shown in FIG. 5, in this embodiment, the developing units 1Y, 1M, 1C, 1
K are arranged in parallel in the horizontal direction. The developer cartridges 5Y, 5M, 5C, and 5K are provided with developing devices 1Y for each color.
The photosensitive belt 28B is disposed above the rotation belts 1M, 1C, and 1K in the rotation path of the photosensitive belt 28B.

FIG. 6 shows the developing device 1 and the developer cartridge 5.
FIG. 6 is a diagram viewed from the left side of FIG. As shown in FIG. 6, the supply port 6a and the supply screw 4, and the magnet 7 and the recovery port 6b are connected further on the back side than the back end surface of the photosensitive belt 28B. That is, both the replenishment developer and the recovered developer are transferred on the back side of the photosensitive belt 28B. Of course, the delivery is not limited to the inner side, and the delivery may be performed at a position that does not hinder the travel of the photosensitive belt 28B.

The method of recovering the developer and the method of controlling the amount of recovery are the same as those in the first embodiment, and a description thereof will be omitted.

As described above, also in the image forming apparatus using the photosensitive belt according to the present embodiment, the developer is gradually changed automatically to achieve high maintainability, and stable over a long period of time. An image can be realized with a simple and low-cost configuration.

Further, by incorporating the developer cartridge in the photosensitive belt, the entire image forming apparatus can be downsized.

Embodiment 3 Next, a third embodiment of the present invention will be described with reference to FIG. In the description of the present embodiment, similarly to the second embodiment, members having the same reference numerals as those of the first embodiment with the suffixes of Y, M, C, and K are yellow, magenta, cyan, and black, respectively. For example, if it is described as the developing device 1, it refers to items common to the developing devices 1Y, 1M, 1C, and 1K of each color.

As shown in FIG. 7, in the image forming apparatus of this embodiment, an image forming station Y, an image forming station M, an image forming station C, and an image forming station K for forming toner images of four colors are intermediate. Transfer belt 24
B are arranged laterally along the horizontal portion. The toner images of the respective colors are formed on the photosensitive drums 28 of the respective image forming stations in the same manner as described in the first embodiment, and the yellow, magenta, cyan and black toner images are formed in the respective image forming stations Y and M. , C, and K are sequentially transferred onto the intermediate transfer belt 24B by the transfer charger 23,
Thereafter, the toner image is collectively transferred onto the recording paper 27 by the secondary transfer charger 23S.

In the intermediate transfer member system as in this embodiment, troubles such as paper jams are less likely to occur because the mechanism for transporting the recording paper 27 is simplified, and various materials such as plain paper and OHP films can be easily applied. It has features such as support.

In the image forming apparatus of this embodiment, the developer cartridges 5 corresponding to the image forming stations Y, M, C, and K are arranged inside the intermediate transfer belt 24B. In the present embodiment, the connection between the supply port 6a and the supply screw 4 and the connection between the magnet 7 and the recovery port 6b are both on the near side of the intermediate transfer belt 24B in FIG. Therefore, the transfer of the developer between the developing device 1 and the developer cartridge 5 does not hinder the running of the intermediate transfer belt 24B.

The method of recovering the developer and the method of controlling the amount of recovery are the same as in the first embodiment, and a description thereof will be omitted.

As described above, even in the image forming apparatus of the intermediate transfer type as in this embodiment, the developer is gradually and automatically replaced to achieve high maintainability, and an image which is stable for a long time can be easily obtained. And it can be realized with a low-cost configuration.

Further, by incorporating a developer cartridge in the intermediate transfer belt, the entire image forming apparatus can be downsized.

Although the image forming apparatus of the present invention has been described with reference to the above three embodiments, the present invention is not limited to the above-described configuration, and various configurations can be adopted based on the present invention.

[0062]

As is apparent from the above description, according to the developer supply / recovery device, the developing device, and the image forming apparatus of the present invention, the developer supply / recovery device is provided in a developing container containing at least toner. A replenishing developer container for storing the replenished developer to be replenished, and a collecting port for collecting the two-component developer in the developing container; and a collecting port for storing the collected developer collected from the collecting port. A recovery developer storage unit formed integrally with the replenishment developer recovery unit, and a two-component developer in or near the recovery container attached to the recovery port and transported to the recovery port. A rotatable magnetic field generating means around an axis, and a peeling member provided to be close to or in contact with the magnetic field generating means, for peeling off the two-component developer attached to the magnetic field generating means, Arranged substantially above the developing container By being, in the configuration of a simple and low cost, to achieve high maintainability, it is possible to obtain a stable image for a long time.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of an image forming apparatus according to the present invention.

FIG. 2 is a side view illustrating an embodiment of the developer cartridge of the present invention.

FIG. 3 is a front view of the developer cartridge of FIG. 2;

FIG. 4 is a diagram for explaining a method of controlling the amount of developer in a developing container.

FIG. 5 is a schematic configuration diagram showing another embodiment of the image forming apparatus according to the present invention.

6 is a side view showing a developer cartridge mounted on the image forming apparatus of FIG.

FIG. 7 is a schematic configuration diagram showing another embodiment of the image forming apparatus according to the present invention.

[Description of Signs] 1 Developing device 2 Developing container 5 Developing cartridge (Developer replenishing and collecting container
Developer supply / collection container) 5a Supply developer container 5b Collection developer container 6a Supply port 6b Collection port 7 Magnet (magnetic field generating means) 8 Scraper (peeling member) 10 Toner density detecting device (toner density detecting means) 24 Intermediate Transfer belt (endless belt-shaped transfer member) 28 Photosensitive drum (image carrier / photoconductor) 28B Photoconductor belt (endless belt-shaped photosensitive member)

Claims (20)

[Claims] 1. A developing container for storing a two-component developer containing a toner and a magnetic carrier for developing an electrostatic latent image formed on an image carrier, and detecting a toner concentration of the two-component developer. A developer supply / recovery device for a developing device provided with a toner concentration detecting means, wherein a replenishment developer accommodating portion accommodating at least a replenishment developer supplied to the developer container, the toner being contained in the developer container; A recovery port for recovering the component developer, a recovery developer storage unit integrally formed with the replenishment developer storage unit for storing the recovery developer recovered from the recovery port, A magnetic field generating means which is arranged near the opening, and which is rotatable about the axis for adhering the two-component developer in or near the developing container and conveying the developer to the collecting opening; Provided in Wherein the magnetic field 2 and the peeling member for peeling the component developer adhering to the generation means has a developer supply recovery device, characterized in that said disposed substantially above the developing container. 2. The method according to claim 1, wherein a recovery amount of the two-component developer adhered to the magnetic field generation unit and transported to the recovery developer storage unit is changed according to the toner density detected by the toner density detection unit. The developer supply and recovery device according to claim 1. 3. The toner concentration detecting means uses a light emitting unit and a light receiving unit disposed on the back side of a light transmissive detection window,
3. The developer replenishing and collecting apparatus according to claim 1, wherein the toner concentration is detected by detecting the amount of received light. 4. The developer supply and recovery device according to claim 1, wherein said toner concentration detecting means detects the toner concentration by detecting the magnetic permeability of a magnetic carrier in said two-component developer. . 5. The developer supply and recovery device according to claim 1, wherein a recovery amount of said two-component developer is changed by changing a rotation amount of said magnetic field generating means. 6. The developer supply and recovery device according to claim 1, wherein said peeling member is a single member or a part of said recovery port. 7. A developing container for storing a two-component developer containing a toner and a magnetic carrier for developing an electrostatic latent image formed on an image carrier, and detecting a toner concentration of the two-component developer. And a toner concentration detecting means, comprising: a developer supply / collection container disposed substantially above the development container; wherein the developer supply / collection container includes at least toner and is supplied to the developer container. A replenishment developer accommodating section for accommodating the supplied replenishment developer, and a recovery port for recovering the two-component developer in the developing container, for storing the recovered developer recovered from the recovery port. A recovery developer storage unit integrally formed with the supply developer storage unit, and a two-component developer in or near the recovery container attached to the recovery port and conveyed to the recovery port. Rotatable around axis A field generating means, provided so as to be close to or in contact with the magnetic field generating means, attached to said magnetic field generating means 2
A peeling member for peeling the component developer. 8. A recovery amount of the two-component developer adhered to the magnetic field generating means and transported to the recovered developer accommodating section is changed according to a toner density detected by the toner density detecting means. The developing device according to claim 7. 9. The image forming apparatus according to claim 1, wherein the toner density detecting unit uses a light emitting unit and a light receiving unit disposed on a back surface side of the light transmitting detection window,
9. The developing device according to claim 7, wherein the toner density is detected by detecting the amount of received light. 10. The developing device according to claim 7, wherein said toner concentration detecting means detects the toner concentration by detecting the magnetic permeability of a magnetic carrier in said two-component developer. 11. The developing device according to claim 7, wherein a recovery amount of said two-component developer is changed by changing a rotation amount of said magnetic field generating means. 12. The developing device according to claim 7, wherein the peeling member is a single member or a part of the recovery port. 13. An image carrier on which an electrostatic latent image is formed, a developing container containing a two-component developer containing a toner and a magnetic carrier for developing the electrostatic latent image, and a developing container for the two-component developer. A developing device having a toner concentration detecting means for detecting the toner concentration, comprising: a developer replenishing and collecting container disposed substantially above the developing container, wherein the developer replenishing and collecting container is at least A replenishment developer storage section containing a replenishment developer to be replenished in the developing container, including a toner, and a collecting port for collecting the two-component developer in the developing container are provided. And a two-component developer disposed in the vicinity of the recovery port and in or near the developing container, for storing the recovered developer in the developing container. Adhere to the front A rotatable magnetic field generating means about an axis for conveying the recovery port is provided in proximity to or in contact with the magnetic field generating means, attached to said magnetic field generating means 2
An image forming apparatus, comprising: a release member for releasing a component developer. 14. A recovery amount of a two-component developer adhered to said magnetic field generating means and conveyed to said recovered developer accommodating section is changed according to a toner concentration detected by said toner concentration detecting means. The image forming apparatus according to claim 13. 15. The toner density detecting means detects the toner density by detecting the amount of received light using a light emitting unit and a light receiving unit disposed on the back side of a light transmissive detection window. The image forming apparatus according to claim 13, wherein: 16. The image forming apparatus according to claim 13, wherein said toner concentration detecting means detects the toner concentration by detecting the magnetic permeability of a magnetic carrier in said two-component developer. 17. The image forming apparatus according to claim 13, wherein a recovery amount of said two-component developer is changed by changing a rotation amount of said magnetic field generating means. 18. The image forming apparatus according to claim 13, wherein the peeling member is a single member or a part of the recovery port. 19. The image bearing member is an endless belt-shaped photosensitive member rotatably provided, and includes a plurality of developing devices arranged in a substantially horizontal direction and a plurality of developing devices for collecting a two-component developer. Wherein the endless belt-shaped photoreceptor is disposed above the plurality of developing devices arranged in the substantially horizontal direction, and the plurality of developer supply and collection containers are 14. The image forming apparatus according to claim 13, wherein the image forming apparatus is disposed inside a rotation path of the endless belt-shaped photoconductor. 20. A plurality of image forming stations including at least the image carrier and the developing device; a plurality of developer supply / collection containers for collecting a two-component developer; An endless belt-shaped transfer member rotatably provided for carrying and transporting the transferred toner image, wherein the plurality of image forming stations are disposed in a substantially horizontal direction, and the endless belt-shaped transfer member is disposed above the image forming stations. 14. The image forming apparatus according to claim 13, wherein a developer supply and recovery container is disposed inside the rotation path of the endless belt-shaped transfer member.