JP2000162873A - Developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device made of a simple structure, with low stress which can lope with the developer for low temp. fixing. SOLUTION: This developing device is, allowed to make the developer which is taken in the developer feeding member 3, capable of being mechanically pulled out and clouded, accompanying the rotation of the developer feeding member 3, arranged and held in contact with a part of the developer flowing path control member 7 and at the same tone to feed only the developer provided with a desired electrostatic charge quantity on the developer carrier 2 by an electric field formed between the developer carrier 2 and the developer feeding member 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as an electrophotographic apparatus and an electrostatic recording apparatus, in which an electrostatic latent image formed on an image carrier is converted into a visible image (toner image) using a developer. And a developing device used for this purpose.

[0002]

2. Description of the Related Art Conventionally, for example, in an image forming apparatus utilizing an electrophotographic system, an electrostatic latent image is formed on a photosensitive member as an image carrier, and these electrostatic latent images are developed with a developer. To form a toner image and transfer the image onto a transfer material to obtain an image.

As such a developing method, there are generally known a one-component developing method using a one-component developer consisting of toner alone and a two-component developing method using a developer consisting of magnetic particles and toner. However, since the one-component developing method has a simpler structure of the developing device and is easier to maintain than the two-component developing method, many developing devices using the one-component developing method have been proposed. ing.

As disclosed in Japanese Patent Application Laid-Open No. 58-116559, there is a non-magnetic one-component developing method using a non-magnetic one-component toner without using a magnetic toner. This development method
It is possible to obtain a color image in response to recent demands for a color image, and furthermore, a low-cost and small-sized developing device is possible and widely used.

FIG. 9 shows an example of a developing device using a conventional non-magnetic one-component developing method.

In this embodiment, the developing device includes a developing container 2 containing a developer, that is, a non-magnetic one-component toner, and a developing roller 2 serving as a developer carrying member rotatably supported by the developing container 1. Driven. A toner supply / collection roller 15 as a developer supply / collection member and a blade 14 as a developer layer thickness regulating member are in contact with the development roller 2. The blade 14 is a support member 14 made of phosphor bronze or the like.
a elastic member 1 such as urethane rubber on the side facing the developing roller
4b is adhered, and has a function of forming a thin layer of the toner on the surface of the developing roller 2 and giving a charge to the toner. Toner supply / recovery roller 15
The outer peripheral surface of a core metal 15a such as SUS is coated with an elastic member 15b such as urethane foam, thereby supplying the toner contained in the developing container 1 to the surface of the developing roller 2 and contributing to the developing process. The toner has a function of scraping the toner that has returned without being cleaned from the surface of the developing roller 2.

With this configuration, a thin layer of non-magnetic one-component toner can be easily formed on the developing roller 2, and the latent image on the latent image carrier can be developed.

[0008]

However, in the developing device using the above-described non-magnetic one-component developing method, the toner supply / recovery roller 15 is brought into contact with the developing roller 2 and is rotated.
The toner is supplied and collected by rubbing. Further, the charge is applied to the toner mainly by contact friction when the toner passes through the blade 14.

That is, in the conventional developing device, the developing container 1
Until the toner inside is subjected to the developing operation of the electrostatic latent image in the developing section, the mechanical load on the toner is extremely large, and the damage is extremely large as compared with other developing methods. I have.

Further, depending on the arrangement position and the rotation direction of the toner supply / recovery roller 15, it may not be possible to completely recover the toner that has not contributed to the development, and the toner may remain on the toner supply / recovery roller 15. was there.
The toner remaining on the toner supply / recovery roller 15 passes through the blade 14 again and is conveyed to the developing unit. However, if such a process is continuously repeated, the toner charge amount and flow In many cases, an external additive or the like that controls the properties is embedded in the toner due to mechanical friction or heat accumulation that occurs each time, resulting in a deteriorated toner that cannot obtain desired charging characteristics and fluidity.

These deteriorated toners cause a number of problems during the image forming process. For example, when the deteriorated toners contribute to the development, defective development due to the inability to obtain proper development characteristics may occur. In some cases, transfer defects such as voids may occur. Further, the developing roller 2
The supply of new toner upward is alienated, and the amount of applied toner is reduced, which may cause a density defect or the like.

When the deteriorated toner is fused to the nip portion of the blade 14 or the surface of the developing roller 2, a coating failure such as a streak occurs, and a charge is applied to the toner newly supplied onto the developing roller 2. Inhibits. For this reason, the uncharged toner is conveyed to the development area, and image formation defects such as fog and unevenness may occur.

Further, according to the developing device, not only the load on the toner is large, but also the load on the developing device itself.

Further, when a sponge-type roller as described above is used as the toner supply / recovery roller 15, if the rubbing of the developing roller 2 takes a long time, the toner supply / recovery roller 15 itself wears, is damaged, and the toner is removed. Clogging and the like, the role of the toner supply and collection roller 15 becomes insufficient, and good toner supply may not be performed.

As described above, the contact one-component developing device using the non-magnetic one-component toner can form a good toner image with a simple structure, but the load on the toner and the developing device is large, The long-term durability and stability are remarkably poor as compared with the magnetic one-component developing device and the two-component developing device.

Therefore, it is mainly used as a cartridge type developing device that replaces the entire developing device at the time of toner replenishment, and is often adopted in a developing device of a type that replenishes a developer such as a copying machine. Not.

In recent years, development of a toner capable of fixing at a lower temperature has been desired due to reduction in power consumption.
A low-stress development process corresponding to these low-temperature fixing toners is expected.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a developing device having a low stress and a simple structure capable of coping with a low temperature fixing developer.

Another object of the present invention is to realize a low-stress coat in which the load applied to the developer used, in particular, the load applied during charging and supply to the developer carrier is remarkably reduced, and a developer replenishing type is provided. An object of the present invention is to provide a non-magnetic one-component contact developing device which can be used for a long time as the developing device.

[0020]

The above object is achieved by a developing apparatus according to the present invention. In summary, the present invention relates to a developing device for developing an electrostatic latent image on an image carrier with a developer, a developing container having a developer accommodating portion for accommodating the developer, and a rotatable container. A rotatable developer carrier that carries the developer and carries the developer,
A power supply for applying a voltage to the developer carrier, and a developer upstream side of a developing unit where the developer carrier and the image carrier are opposed to each other with respect to a rotation direction of the developer carrier, and A developer supply member rotatably arranged in a non-contact manner, and a developer supply member upstream of a position where the developer carrier and the developer supply member face each other with respect to a rotation direction of the developer supply member and the developer supply member; A developer flow path control member disposed so that a part thereof contacts the member, a power supply for applying a voltage to the developer supply member, and an upstream side of the developing unit with respect to a rotation direction of the developer carrier. A developer layer thickness regulating member disposed downstream of the developer flow path control member; and a developer downstream of a developing unit where the developer carrier and the image carrier are opposed to each other. Recovery of developer installed in non-contact with carrier And a developer stripping member for collecting a developer from the developer collecting member into the developer accommodating portion, and a developer residue collected from the developer carrier by the developer collecting member. The developer is peeled off from the developer collecting member by the developing stripping member,
The developing device is collected in the developer accommodating section.

According to one embodiment of the present invention, the developer peeling member is disposed such that the tip thereof is in contact with the developer collecting member, and the developer remaining member is directly transferred from the developer collecting member to the developer accommodating portion. A developer scraping member for scraping off the developer.

According to another embodiment of the present invention, there is further provided a partition member for preventing the undeveloped developer scraped off by the developer stripping member from being directly supplied to the developer supply member. It is provided in the developer accommodating section.

According to another embodiment of the present invention, the developer supply member is a roller-shaped toner supply brush, and the developer flow path control member is a thin metal plate, one end of which is connected to the toner supply brush. In contact. Further, the developer collecting member is a metal roller and is grounded, and the developer peeling member has a rubber elastic body whose tip abuts on the roller surface. Further, the surface of the metal roller is subjected to surface processing using a fluororesin.

According to the present invention, the developer is preferably a non-magnetic one-component toner.

According to another aspect of the present invention, a developer carrier that carries a developer and conveys the developer to a development area facing the image carrier, and a first housing that stores the developer to be supplied to the developer carrier. A storage part, a second storage part for storing the developer to be supplied to the first storage part, and a supply part which is provided in the first storage part and supplies the developer to the developer carrier in a non-contact state. A developing device having a member, a stirring member provided in the second storage portion for stirring the developer, and a peeling unit for peeling the developer passing through the developing region from the developer carrier in a non-contact state. The developing device is provided, wherein the developer peeled from the developer carrier by the peeling means is guided to the second storage section.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a developing device according to the present invention will be described in more detail with reference to the drawings.

Embodiment 1 FIG. 1 shows a first embodiment of the developing device of the present invention. In the present embodiment, the developing device includes the developing container 1 and the developing container 1
As shown in FIG. 2, a region A as a developer accommodating portion accommodating a developer, that is, a non-magnetic one-component toner, a region B as a developer supplying portion, and a region as a developer collecting portion as shown in FIG. It is constituted by a region C.

A developing roller 2 as a developer carrying member is rotatably carried in the developing container 1, and an image carrying member on which an electrostatic latent image is formed, for example, a drum-shaped electrophotographic photosensitive member, that is, a photosensitive member. A developing unit that faces the drum 100 and forms an electrostatic latent image on the photosensitive drum 100 as a visible image (toner image) is formed. The developing roller 2 also faces a roller-shaped toner supply brush 3 as a developer supply member that supplies toner to the development roller 2, and forms a developer supply section B. The developing roller 2 and the toner supply brush 3 are driven to rotate in the direction of the arrow.

A developing bias power supply 4 is connected to the developing roller 2, and a desired developing bias voltage in which an AC voltage is superimposed on a DC voltage is applied. In the present embodiment, the core metal 5 of the toner supply brush 3 is connected to the developing bias power supply 4 via a DC power supply 6, and a desired electric field is formed between the core and the developing roller 2.

Although the developing roller 2 is a metal roller in the present embodiment, the material is not limited to a metal roller. For example, the developing roller 2 is brought into contact with the photosensitive drum 100 to perform development. When using the contact development method of performing
An elastic developing roller having a single layer or a plurality of elastic layers on a cored bar may be used. In this case, as the material of the elastic layer, a general rubber material such as silicone rubber, NBR rubber, EPDM rubber, urethane rubber or the like can be used, and furthermore, the surface of the elastic layer is dispersed with carbon or the like in a resin such as nylon. It is also possible to use a resin coated with the conductive resin film. The rubber hardness of the elastic layer, including the surface conductive film,
It is suitably measured at 20 to 70 degrees using a JIS A rubber hardness meter. The surface roughness of the elastic layer is desirably 1 to 20 μm in Rz value in consideration of toner transportability, and is appropriately set in accordance with the particle size and shape of the toner to be used. You. The volume resistance of the elastic developing roller is 10 ³ to 10 ⁹ Ω including the conductive resin film.
-It is desirable to set to about cm.

The toner supply brush 3 for supplying the non-magnetic one-component toner in the developing container 1 to the developing roller 2 has a distance S ₁ from the developing roller 2 of about 100 μm to ₁ mm. It is installed to be rotatable in the same direction as the direction (in the opposite direction at the closest part).

Although the fibers constituting the toner supply brush 3 may be only conductive fibers, in the present embodiment, as shown in FIG. 5, the conductive fibers 3a having low-resistance electrical characteristics are used.
(10 ² to 10 ⁸ Ω · cm) and high-resistance insulating fiber 3
b (10 ⁸ to 10 ¹⁵ Ω · cm) A fur brush is used in which a brush member in which two kinds of hair are mixed is wound around a metal core such as SUS.

Further, in this embodiment, since the non-magnetic one-component toner having a negative charge polarity is used as the developer, the insulating fiber 3b constituting the toner supply brush 3 has a positive charge characteristic. Is desirable. Therefore, in this embodiment, the insulating fiber made of nylon (10 ⁸ to 10 ¹⁵ Ω ·
cm) was used. Needless to say, the insulating fiber is not limited to nylon, and an appropriate insulating fiber may be selected according to the characteristics of the toner. In the case of this embodiment, a material such as rayon may be used.

On the other hand, the first condition is that the conductive fiber 3a satisfies the above-mentioned volume resistance value. However, most of the conductive fiber 3a is obtained by dispersing a conductive resin such as carbon into insulating fiber and spinning. In many cases, the dispersion method is different among fiber manufacturers, and the conductive resin is not always exposed on the entire yarn surface. That is, as can be understood from the cross section of the conductive fiber 3a shown in FIG. 6, since the insulating portion E exists on the surface of the conductive fiber 3a in addition to the conductive portion D, the contact between the toner and the insulating portion E can be prevented. In consideration of this, it is desirable to select a material having a positive charge characteristic for the toner as a basic constituent material of the conductive fiber 3a. Therefore, in the present embodiment, the nylon-based conductive fiber 3a was used.

Since the fibers 3 used in the present embodiment need elasticity for forming the toner into a cloud,
Both the conductive fiber 3a and the insulating fiber 3b have a fineness of 1
The densities were set to about 10 to 10 denier / filament, and when they were mixed, the planting density was 1 to 200,000 filaments / (inch) ² and the pile length was 1 to 10 mm.

The developing device further includes a developer flow path control member 7 for clouding the toner from the toner supply brush 4 and tapping the toner toward the developing roller 2. The developer flow path control member 7 is arranged so that a part thereof is in contact with the toner supply brush 3. In this embodiment, for example, the developer flow path control member 7 has a thickness of 100 μm.
It is made of a thin metal plate of about m to 1 mm. In this embodiment, as shown in FIG. 1, a straight thin plate is used, but the shape is not limited to this, and it can be formed into a desired shape depending on the direction of clouding the toner.

In consideration of charging of the toner interposed on the contact surface between the developer flow path control member 7 and the toner supply brush 3, the developer flow path control member 7 applies the toner to the contact surface with the brush. On the other hand, a resin having a high charge applicability, for example, a resin in which carbon is dispersed in nylon may be laminated. By adopting such a configuration, the charging of the toner is more stabilized.

According to the present embodiment, the developing device has the developer layer thickness regulating member 8 which contacts the developing roller 2 and regulates the layer thickness of the toner applied to the developing roller 2. In the present embodiment, the developer layer thickness regulating member 8 has a metal thin plate 8a having a thickness of about 0.1 mm and a JIS A rubber hardness meter laminated at the tip of the thin plate 8a having a thickness of 50 to 70 degrees. An elastic body 8b made of a rubber material such as urethane or silicon.

When the above-mentioned elastic developing roller is used as the developing roller 2, the developer layer thickness regulating member 8 is set to 0.1.
It is desirable to use a thin metal plate 8a having a thickness of about mm. Further, it is bent in a direction opposite to the elastic developing roller at a position of about 2 mm from the front end, and the bent portion comes into contact with the elastic developing roller at a linear pressure of about 20 g / cm.

The undeveloped developer on the developing roller 2 that has not contributed to the development, that is, the undeveloped toner is collected by a toner collecting member C as a developer collecting member disposed adjacent to the developing roller 2. The collecting roller 9 electrically peels off the surface of the developing roller, returns the developing roller 1 to the inside of the developing container 1, and thereafter,
It is again provided to the developing section for performing the developing step.

In this embodiment, the toner collection roller 9 is rotatable in a direction opposite to the rotation direction of the development roller 2 (the same direction at the closest part) when the distance S _{2 from the} development roller 1 is about 100 μm to 1 mm. It is installed in. In this embodiment, a cylindrical metal member having a mirror-finished surface is used as the toner collecting roller 9 and is electrically grounded. However, in consideration of the releasability of the toner to be collected, the surface of the roller is made of Teflon. Surface treatment using a fluorine-based resin such as For example,
The roller surface formed by quenching nickel, chrome, etc. on the roller surface and dissolving the fluororesin into cracks on the plating surface formed at that time enhances the toner releasability, while the fluororesin Due to the electric field concentration effect of the (insulating portion) and the plating (conductive portion), the undeveloped toner is more easily collected.

The toner collected by the toner collecting roller 9 is separated from the surface of the toner collecting roller 9 and the developer storing section A
Developer stripping member (scraper) 10 to return to
Is arranged. In this embodiment, the scraper 10 is 1 mm
A thin metal plate 10a having a thickness of about
An elastic body 10b, which is a rubber material such as urethane or silicon, having a JIS A rubber hardness tester of 50 to 70 degrees laminated on Oa. The elastic body 10 b is arranged such that the front end (edge) contacts the surface of the toner collecting roller 9, and is configured to mechanically scrape the toner from the toner collecting roller 9. Further, the scraped toner is supplied to the stirring member 1.
1 falls into the developer accommodating section A in which the stirring member 1 is disposed.
1 supplies the toner to the toner supply brush 3.

As described above, according to the present embodiment, the edge position of the scraper 10 is set such that most of the toner scraped off from the toner collecting roller 9 is surely returned to the developer accommodating section A.

The toner used in this embodiment is a non-magnetic one-component toner having a weight-average diameter of 5 μm or more, a colorant mixed and dispersed in a thermoplastic resin, and pulverized. Used resins such as polystyrene and polyester containing a negative charge control agent.

According to the present embodiment, an OPC photosensitive member is used for the photosensitive drum 100, the photosensitive drum 100 is uniformly charged with a negative polarity by a primary charger, and then imagewise exposed by an exposure unit. Then, an electrostatic latent image was formed on the photosensitive drum 100, and the electrostatic latent image was reversely developed to obtain a toner image. That is, the electrostatic latent image on the photosensitive drum 100 is
By applying a developing bias voltage, which is a superimposed voltage of a negative direct current (DC) voltage and an alternating current (AC) voltage, to the developing roller 2, reversal development was performed with a negative non-magnetic one-component toner.

The operation of the developing device of the present invention will be described. The toner in the developer accommodating portion A of the developing container 1 is sent to the toner supply brush 3 by the stirring member 11, and comes into contact with the mixed fibers of the toner supply brush 3. To be negatively charged.

At this time, as shown in FIG.
Is carried between the fibers of the toner supply brush 3 and on the surface thereof by an adhesive force such as a mirror force, and is conveyed toward the developer flow path control member 7 with the rotation of the toner supply brush 3. Toner T conveyed to a contact portion with developer flow path control member 7
7 is charged more stably by coming into contact with the developer flow path control member 7 and, after passing through the toner supply brush 3, is repelled in the rotation direction of the brush 3 by the elastic force of the fiber. As shown in the figure, the arrow X
Fly in the direction of. Further, an electric field formed between the toner supply brush 3 and the developing roller 2 by a developing bias voltage applied to the developing roller 2 by the power supply 4 and a voltage applied to the toner supply brush 3 by the power supply 6
The toner T is attracted and carried on the surface of the developing roller 2 in the direction of arrow Y.

For example, as shown in FIG. 8, when the DC component of the developing bias voltage is set to Vdc = −350 V, the power supply 6 superimposes a DC voltage of about ΔV = −750 V on this developing bias voltage. Is applied to the toner supply brush 3, the negatively charged toner T flies from the toner supply brush 3 to the developing roller 2 by the action of the electric field due to the difference between the DC voltages.

The configuration in which the toner supply brush 3 is brought into contact with the developer flow path control means 7 to strike out the toner T in the brush can prevent clogging of uncharged toner and the like remaining between the brush fibers.

The toner supplied on the developing roller 2 in this manner is carried on the developing roller 2 by a mirror image, and is then conveyed to a blade 8a which is a developer layer thickness regulating member 8, and the blade 8a From 8a, the toner layer is made thinner and further triboelectric charge is applied. By this step, a thin and dense toner layer having a uniform charge amount distribution is formed.

According to the developing device of the present invention, as described above, the charged toner is once clouded, and the toner is supplied onto the developing roller 2 in a non-contact manner by the electric field coating, whereby the mechanical stress on the toner is reduced. In addition, since only a sufficiently charged toner is supplied to the developing roller 2, the distribution of the charge amount in the toner layer is very small, and the sharpness is achieved. Image can be obtained.

On the other hand, the toner that has not returned to the developing container 1 while being carried on the developing roller 2 without contributing to the development in the developing section is formed at the closest portion between the toner collecting roller 9 and the developing roller 2. The toner collecting roller 9 is electrostatically charged by the applied electric field.
Supported and collected on the surface. The collected toner is conveyed into the developing container with the rotation of the toner collecting roller 9, and is scraped off by the scraper 10 into the developer accommodating portion A.

By using the cylindrical toner collecting roller 9 and the scraper 10 as described above, the surface of the toner collecting roller 9 is always a fresh electrode surface with respect to the developing roller 2. And the developing roller 2. In this way, the undeveloped toner is completely removed from the developing roller 2, and the
By making the toner circulation path such that the toner is reliably collected, the toner is not subjected to a continuous load and is prevented from generating heat, so that the promotion of toner deterioration can be minimized. As a result, the life of the toner is remarkably extended, and a good image can be formed over a long period of time.

Embodiment 2 FIG. 3 shows a developing device according to a second embodiment of the present invention. In the developing device described in the first embodiment, the scraper 10 serving as a toner stripping member is configured to collect the undeveloped toner collected on the toner collecting roller 9 into the developer accommodating portion A, whereby the toner is removed. Although the configuration is such that the load is not continuously received, in the present embodiment, as shown in FIG. 3, a partition member 12 as a partition is further provided between the developer accommodating portion A and the developer supply portion B. Thus, it is possible to more reliably collect the developer in the developer storage section A.

FIG. 4 shows a schematic configuration of the partition member 12. According to the present embodiment, the partition member 12 is provided with an opening 12a for supplying the developer at a lower portion thereof,
The tip 12b is about 10 to 500 μm with the developing roller 2.
They are installed with an interval S ₃ of m.

The toner in the developer accommodating section A is
1, an opening 1 provided below the partition member 12
2a, the developer is supplied to the developer supply section B.
The size of 2a is appropriately set in accordance with a desired toner feed amount.

Also in this embodiment, the toner supplied to the developer supply member, that is, the toner supply brush 3,
In the same manner as in the first embodiment, the toner is supplied to the developing unit that performs the developing process. In this embodiment, however, the undeveloped toner on the developing roller 2 is collected by the toner collecting roller 9 and the collected toner is collected. Is further scraped off by the scraper 10. At this time, in this embodiment, since the partition member 12 is provided, the scraped toner does not scatter to the developer supply unit B side. Therefore, it is possible to more reliably return the undeveloped toner to the storage section.

In the partition member 12, of the toner formed into a cloud in the developer supply unit B, the toner that does not have a desired charge passes through the gap between the developing roller 2 and the toner collecting roller 9 and scatters. It is also effective against phenomena.

[0059]

As described above, the developing device according to the present invention has a developer accommodating portion for accommodating a developer in a developing device for developing an electrostatic latent image on an image carrier with a developer. A developing container, a rotatable developer carrier rotatably supported by the developing container, and carrying and transporting the developer; a power supply for applying a voltage to the developer carrier; and rotation of the developer carrier. A developer supply member disposed rotatably upstream of the developing unit where the developer carrier and the image carrier are opposed to each other in the direction and rotatably in non-contact with the developer carrier; and rotation of the developer supply member. and placed developer flow path control member so that the part and the developer supplying member upstream of the opposing position of the developer carrying member and the developer supplying member contacts to the direction, the developer supplying member and the developing a power source for applying a voltage to the agent passage control member, the developer carrying A developer layer thickness regulating member disposed upstream of the developing section and downstream of the developer flow path control member with respect to the rotation direction of the developing section; and a developing section in which the developer carrier and the image carrier are opposed to each other. A developer collection member provided on the downstream side and in non-contact with the developer carrier, and a developer stripping member for collecting the developer from the developer collection member into the developer storage unit; The developer remaining developer recovered from the developer carrier by the developer recovery member is peeled off from the developer recovery member by the development peeling member, and is recovered in the developer accommodating portion. With the rotation of the developer supply member which is arranged in contact with a part of the control member, the developer taken in the developer supply member is mechanically ejected to form a cloud, and at the same time, the developer carrier and the developer supply The electricity formed between members Accordingly, it is possible to provide only the desired charge amount of the developer which has on the developer carrying member. Therefore, according to the present invention, (1) the conventional contact supply, that is, the contact between the toner supply roller and the developer carrier and the supply by rubbing can be avoided, and the stress at the time of the developer supply is remarkably reduced. It becomes possible to reduce. (2) In addition, since a developer having an appropriate charge amount is selectively supplied from the clouded developer, not only is it difficult to supply an uncharged or reversal developer, but also the regulation of the developer layer thickness is consequently restricted. The charge applied to the developer by the member is reduced. That is, the contact pressure of the developer layer thickness regulating member can be reduced, and the load on the developer can be further reduced. (3) Further, the developer returned without contributing to the developing process is electrostatically peeled off by a developer collecting member arranged in non-contact with the developer carrying member, and further, from the developer collecting member. The developer is reliably returned to the developer accommodating portion by the developer stripping member. By adopting a configuration having a developer circulation path in the developing device in this way, the developer that did not contribute to development is
Since the developer does not repeatedly pass through the nip portion of the developer layer thickness regulating member, a continuous load is not applied to the developer, and embedding of an external additive or the like due to heat storage or the like can be significantly suppressed. That is, the developer is configured to radiate heat generated by the pressure applied to the nip portion of the developer layer thickness regulating member during the circulation. (4) From the above, the developing device of the present invention can significantly reduce the load of the developer in the developing process for a long period of time and can form high-quality images without fog or the like.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of a developing device of the present invention.

FIG. 2 is a schematic configuration diagram of a developing device of the present invention.

FIG. 3 is a cross-sectional view showing a second embodiment of the developing device of the present invention.

FIG. 4 is a schematic perspective view of a partition member.

FIG. 5 is a partially enlarged perspective view of a roller-shaped toner supply brush.

FIG. 6 is a cross-sectional view of one embodiment of a fiber constituting a brush.

FIG. 7 is a diagram illustrating a toner supply method in the developing device of the present invention.

FIG. 8 is a diagram illustrating a bias configuration according to an embodiment during toner supply.

FIG. 9 is a sectional view of a conventional developing device.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 development container 2 developer carrier (development roller) 3 developer supply member (toner supply brush) 4 development bias power supply 5 toner supply brush core 6 toner supply brush power supply 7 developer flow path control member 8 developer layer thickness Control member (blade) 9 Developer collecting member (toner collecting roller) 10 Developer stripping member (scraper) 11 Stirring member 12 Partition member 100 Image carrier (photosensitive drum)

Claims (9)

[Claims] 1. A developing device for developing an electrostatic latent image on an image carrier with a developer, a developing container having a developer accommodating portion for accommodating the developer, and rotatably carried by the developing container. A rotatable developer carrier that carries and conveys the developer, a power supply that applies a voltage to the developer carrier, and a developer carrier that rotates with respect to a rotation direction of the developer carrier. A developer supply member disposed rotatably upstream of a developing unit facing the image carrier and in a non-contact manner with respect to the developer carrier; and the developer with respect to a rotation direction of the developer supply member. A developer flow path control member disposed upstream of a position where the carrier and the developer supply member face each other and a part of the developer supply member is in contact with the developer supply member; and applying a voltage to the developer supply member. Power supply, and a method of rotating the developer carrying member. A developer layer thickness regulating member disposed upstream of the developing unit and downstream of the developer flow path control member, and a developing unit in which the developer carrier and the image carrier are opposed to each other. A developer collection member provided on the downstream side and in non-contact with the developer carrying member, and a developer stripping member for collecting a developer from the developer collection member into the developer accommodating portion, Having the developer recovery member recovered from the developer carrier by the developer recovery member, peeling off the developer recovery member from the developer recovery member by the development stripping member, and recovering the developer in the developer storage unit. Characteristic developing device. 2. The developer peeling member is disposed such that the tip thereof is in contact with the developer collecting member, and scrapes off the residual developer from the developer collecting member directly into the developer accommodating portion. The developing device according to claim 1, wherein: 3. A developer storage unit further comprising a partition member for preventing the undeveloped developer scraped off by the developer stripping member from being directly supplied to the developer supply member. 3. The developing device according to claim 1, wherein: 4. The developer supply member is a roller-shaped toner supply brush, and the developer flow path control member is a thin metal plate, one end of which is in contact with the toner supply brush. The developing device according to claim 1, 2 or 3, wherein 5. The developer recovery member is a metal roller, and the developer stripping member has a rubber elastic body whose tip abuts on the roller surface. The developing device according to any one of the above items. 6. The developing device according to claim 5, wherein said metal roller is grounded. 7. The developing device according to claim 5, wherein the surface of the metal roller is subjected to surface processing using a fluorine-based resin. 8. The developing device according to claim 1, wherein the developer is a non-magnetic one-component toner. 9. A developer carrier for carrying a developer and transporting the developer to a development area facing the image carrier, a first accommodating portion for accommodating a developer to be supplied to the developer carrier, A second storage unit that stores the developer to be supplied to the storage unit;
A supply member that is provided in the storage section and supplies the developer to the developer carrier in a non-contact state; a stirring member that is provided in the second storage section and stirs the developer; And a peeling means for peeling the passed developer from the developer carrier in a non-contact state. The developer peeled from the developer carrier by the peeling means is guided to the second storage section. A developing device.