JP2001209244A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To replenish a developing device using two-component developer with toner or carrier from a simplified developer supply part without retaining it halfway so as to maintain the toner concentration in the developer and the developing ability. SOLUTION: A toner hopper 200T and a carrier hopper 200C are arranged in parallel, and the carrier in the hopper 200 C is made to drop to the upstream part of a carrying screw 300A being a toner supply means, and is supplied to the developing device 14 together with the toner.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention develops a latent image on an image forming body with a two-component developer comprising a carrier and a toner to form a toner image, and includes a supply unit and a discharge unit for the carrier and the toner. The present invention relates to an image forming apparatus using a developing device.

[0002]

2. Description of the Related Art In an electrophotographic image forming apparatus,
A latent image is formed by performing image exposure on a uniformly charged image forming body, developing the latent image into a toner image, and then transferring the toner image to a transfer material such as recording paper. As the transfer material carrying the toner image passes through the fixing device, the toner is fixed on the transfer material.

In developing a latent image, a two-component developer composed of a toner and a carrier is often used because of its excellent developability. The toner and the carrier are agitated in the developing device, and the toner is electrostatically attached to the outer surface of the carrier. The toner is conveyed to the developing area and the toner is separated from the carrier under the condition that the developing bias is applied, and the toner is separated from the carrier. Electrostatically adheres to the latent image portion of. Since toner is consumed by development in the developing device, a toner concentration detecting means for detecting the amount of toner in the developer using an inductance or the like is provided in the developing device, and when the toner falls below a predetermined ratio, A toner is supplied from a toner supply unit such as a toner hopper into a developing device.

[0004] The toner in each developing unit is replenished for the shortage by the consumed new toner, but the carrier is continuously used. When the carrier is used for a long period of time, fine toner of less than 1 μm adheres to the outer periphery of each carrier, and as a result, the developing performance gradually decreases and a good toner image is obtained. Will not be. For this reason, when a predetermined number of images have been formed, good development is performed again by removing each of the developing devices arranged in the vicinity of the image forming body, replacing the internal developer, and replacing it with a new carrier. Service business was performed.

[0005] From such a situation, a new carrier is added at a fixed ratio together with the toner to be replenished and replenished, and the carrier having deteriorated developing performance is gradually replaced with a new carrier, whereby the developer is replaced as a service business. Has been proposed by Japanese Patent Publication No. 2-15991 (hereinafter referred to as "trickle development").

Further, a developing device containing a plurality of developers having different toner colors such as Y, M, C, and K is provided at a peripheral portion of the rotating image forming body, and a toner image is superposed on the image forming body. A color image forming apparatus for forming a color toner image and transferring the color toner image to a transfer material at once is provided by the present applicant. This type has a feature that the color image forming apparatus can be miniaturized by effectively arranging a charger, a developing device and a cleaner around the image forming body without providing an extra space. In such a color image forming apparatus, the consumption of the toner inside the developing unit is detected, and the toner is replenished based on the detection result.

[0007]

In the conventionally proposed trickle development, a carrier having a fixed ratio with the toner has been supplied in proportion to the toner consumption. However, in such a developer replenishing method, the frequency of use of the toner and the deterioration of the developer are inversely proportional, and the characteristics of the carrier significantly change depending on the use condition of the image forming apparatus. Differences are coming.

The present invention is directed to a developing apparatus in which good development is continuously performed without replacing the developer for a long period of time, and a color image in which a plurality of developing devices are arranged close to the periphery of an image forming body. In the image forming apparatus, each developing unit always maintains good developing conditions without requiring the operation of changing the developer, and an image forming apparatus capable of obtaining a good color image stably over a long period of time. And an image forming apparatus in which the supply path and the supply method are simplified, the carrier is mixed with the toner and supplied, and the independent supply of the carrier and the toner is performed. It is another object of the present invention to provide an image forming apparatus as described above, wherein the toner storage unit and the carrier storage unit are integrally configured to simplify the storage unit.

[0009]

An object of the present invention is to supply a toner from a toner storage unit and a carrier from a carrier storage unit to a developing device having a two-component developer composed of a toner and a carrier. 2. The image forming apparatus according to claim 1, wherein the carrier is supplied to the toner supply means from above the toner reservoir in the toner storage section. And supplying a toner from a toner storage unit and a carrier from a carrier storage unit to a developing device having a two-component developer including a toner and a carrier, and recovering the developer from the developing device. In the image forming apparatus, the toner accommodating section and the carrier accommodating section are arranged in parallel, and the carrier is supplied to toner supply means and is supplied together with the toner. It is achieved by an image forming apparatus characterized by being configured to supply to the image device (the invention of claim 3).

The above object is to supply a toner from a toner storage section and a carrier from a carrier storage section to a developing apparatus having a two-component developer composed of a toner and a carrier, and to collect the developer from the developing apparatus. In the image forming apparatus, the toner accommodating section and the carrier accommodating section are arranged in parallel and have a common supply unit to the developing device, and the supply unit can be selectively opened or closed. This is achieved by an image forming apparatus (invention of claim 6), wherein means are provided in each storage section.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An image forming apparatus according to the present invention includes a developing device using a two-component developer, and is characterized by means for supplying toner and carrier to the developing device. FIG. 1 shows an image forming process and each mechanism of a color printer which is an example of an image forming apparatus equipped with a plurality of such developing devices.
This will be described with reference to FIG. FIG. 1 is a cross-sectional view of a color printer as an example of an image forming apparatus equipped with a plurality of sets of the developing device of the present invention, and FIG. 2 is a cross-sectional view of the image forming body.

The description of the present application does not limit the technical scope of the claims and the meaning of the terms. Further, the following assertive description in the embodiment of the present invention indicates the best mode, and does not limit the meaning or technical scope of the terms of the present invention.

According to FIG. 1 or FIG. 2, a photosensitive drum 10, which is an image forming body, is provided on the outer periphery of a cylindrical base formed of a light-transmitting member such as glass or light-transmitting acrylic resin. It is formed by forming a photoconductive layer and a photoconductor layer of an organic photosensitive layer (OPC).

The photoreceptor drum 10 is rotated clockwise as indicated by an arrow in FIG. 1 in a state where the light-transmitting conductive layer is grounded by power from a driving source (not shown).

In the present invention, the exposure beam for image exposure is:
The photoconductor layer of the photoconductor drum 10, which is the image forming point, only needs to have an exposure light amount of a wavelength that can provide an appropriate contrast with respect to the light attenuation characteristic (photocarrier generation) of the photoconductor layer. . Therefore, the light transmittance of the light-transmitting substrate of the photosensitive drum in the present embodiment does not need to be 100%, and may have a characteristic of absorbing a certain amount of light when transmitting the exposure beam. . The point is that any suitable contrast can be provided. As a material of the light-transmitting substrate, an acrylic resin, particularly one obtained by polymerizing a methyl methacrylate monomer, is preferably used because of its excellent light-transmitting properties, strength, accuracy, surface properties, etc. Various translucent resins such as acryl, fluorine, polyester, polycarbonate, polyethylene terephthalate and the like used for the above can be used. Further, as long as it has a light-transmitting property with respect to the exposure light, it may be colored. As the light-transmitting conductive layer, indium tin oxide (I
TO), tin oxide, lead oxide, indium oxide, copper iodide, or a metal thin film of Au, Ag, Ni, Al, or the like that maintains light transmissivity. Reactive deposition method, various sputtering methods, various CV
D method, dip coating method, spray coating method and the like can be used.
Various organic photosensitive layers (OPC) can be used as the photoconductor layer.

The organic photosensitive layer serving as the photosensitive layer of the photoconductor layer includes a charge generation layer (CGL) mainly composed of a charge generation substance (CGM) and a charge transport layer (CTM) mainly composed of a charge transport substance (CTM). And CTL). An organic photosensitive layer having a two-layer structure has high durability as an organic photosensitive layer due to its thick CTL and is suitable for the present invention.
The organic photosensitive layer may have a single layer structure containing a charge generation material (CGM) and a charge transport material (CTM) in one layer. ,
Usually, a binder resin is contained.

A scorotron charger 11 as a charging unit described below, and an exposure optical system 1 as an image writing unit will be described.
2. The developing device 14 as a developing unit is prepared for an image forming process for each color of yellow (Y), magenta (M), cyan (C), and black (K), respectively. Are arranged in the order of Y, M, C, and K with respect to the rotation direction of the photosensitive drum 10 indicated by the arrow in FIG.

Scorotron charger 11 as charging means
Is mounted so as to face and be close to the photosensitive drum 10 in a direction perpendicular to the moving direction of the photosensitive drum 10 as an image forming body (the direction perpendicular to the plane of FIG. 1). A control grid (no symbol) maintained at a predetermined potential with respect to the body layer;
As a, for example, a sawtooth electrode is used, and a charging action (in this embodiment, negative charging) is performed by corona discharge having the same polarity as that of the toner, thereby giving a uniform potential to the photosensitive drum 10. As the corona discharge electrode 11a, a wire electrode or a needle electrode may be used.

The exposure optical system 12 for each color is a linear exposure element (LED) in which a plurality of LEDs (light emitting diodes) as light emitting elements of image exposure light are arranged in an array parallel to the axis of the photosensitive drum 10. (Not shown) and a selfoc lens (not shown) as an equal-magnification imaging element are configured as an exposure unit attached to a holder. Cylindrical holding member 2
At 0, the exposure optical system 12 for each color is attached and housed inside the base of the photosensitive drum 10. In addition, as the exposure element, a linear element in which a plurality of light emitting elements such as FL (phosphor emission), EL (electroluminescence), and PL (plasma discharge) are arranged in an array is used.

An exposure optical system 12 as an image writing means for each color sets an exposure position on the photosensitive drum 10 between the scorotron charger 11 and the developing unit 14 with respect to the developing unit 14. It is arranged inside the photoconductor drum 10 in a state provided on the upstream side in the rotation direction of the drum 10.

The exposure optical system 12 performs image processing based on image data of each color sent from a separate computer (not shown) and stored in a memory, and then forms an image on the uniformly charged photosensitive drum 10. Exposure is performed to form a latent image on the photosensitive drum 10. The emission wavelength of the light-emitting element used in this embodiment is usually 6 for the toners of Y, M, and C, which have high translucency.
The wavelength in the range of 80 to 900 nm is good, but the wavelength may be shorter than this, since the color toner does not have sufficient translucency since image exposure is performed from the back surface.

The developing device 14 as a developing means for each color contains a two-component developer of yellow (Y), magenta (M), cyan (C) or black (K) therein, as will be described later. , Respectively, for example, a thickness of 0.5 to 1 mm,
A developing sleeve 141 as a developer carrier made of a cylindrical non-magnetic stainless steel or aluminum material having an outer diameter of 15 to 25 mm is provided.

In the developing area, the developing sleeve 141 is kept out of contact with the photosensitive drum 10 with a predetermined gap, for example, 100 to 1000 μm, by abutting rollers (not shown). At the closest position, it rotates in the forward direction. At the time of development, an AC voltage AC is superimposed on a DC voltage of the same polarity as toner (minus polarity in this embodiment) or a DC voltage with respect to the developing sleeve 141 during development. By applying the developing bias voltage, non-contact reversal development is performed on the exposed portion of the photosensitive drum 10. At this time, the precision of the development interval needs to be about 20 μm or less in order to prevent image unevenness.

As described above, the developing device 14 transfers the electrostatic latent image formed on the photosensitive drum 10 formed by the charging by the scorotron charger 11 and the image exposure by the exposure optical system 12 in a non-contact state. Reversal development is performed with toner having the same polarity as the charge polarity of No. 10 (in the present embodiment, the photosensitive drum is negatively charged, and the toner has negative polarity).

As shown in FIG. 2, the photosensitive drum 10 and the holding member 20 are located at the rear and front ends of the apparatus.
Flange members 10A and 10B, which are support members for rotatably supporting the photosensitive drum 10, respectively, and a holding member 20
Are integrally formed with the flanges 120A and 120B for supporting by pressing means or means such as screws. The photosensitive drum 10 has a flange member 10 as a support member.
A and the flange member 10B are shafts 12 which are fixed members integrally formed with the flange 120A of the holding member 20.
1 and the flange 120B are rotatably supported via bearings B1 and B2, respectively.

The shaft 121 has a shaft portion 121A for holding the photoreceptor drum 10, and a support shaft 130 as a holding means for the shaft 121 having an engagement hole 130A is provided on the rear device board 70. I have. Engagement hole 130
A is fitted with a linear bearing B4, and the support shaft 130 is fixed to the rear device substrate 70 by screws or the like with the receiving member 130a interposed therebetween. The support shaft 130 is located at the center of the gear G2 that meshes with the drive gear G1, and rotatably supports a conductive member 131 that integrates the gear G2 via a bearing B3. On the other hand, the device substrate 70 on the front side of the device
An opening 70 </ b> A that allows the photosensitive drum 10 that integrates the exposure optical system 12 fixed to the holding member 20 to be inserted and removed is opened.

The holding member 20 inserts the shaft portion 121A of the shaft 121 into the linear bearing B4 provided on the support shaft 130 with respect to the device board 70 on the rear side, and
A of the engagement pin 121 of the support shaft 130
By engaging the V-shaped groove formed in 30B and restricting the angular position of the exposure optical system 12, the exposure optical system 12 is attached to the device board 70. The front cover 120D is mounted at a predetermined position by fixing the front cover 120D with the screw 52 while pressing the front cover 120D in the axial direction with the buffer material K interposed therebetween.

The coupling 10C, which is an engagement member attached to the side surface of the flange member 10A, which is a support member for supporting the photoreceptor drum 10, and the driving member, which is a coupling member attached to the side surface of the conductive member 131 that integrates the gear G2. The flange member 10 is formed by the pin 131A and the set screw 51.
A coupling portion between the gear A and the gear G2 is formed, and when the photosensitive drum 10 having the holding member 20 integrated therewith is mounted, the coupling 10C attached to the side surface of the flange member 10A.
Is fitted into a drive pin 131A attached to the side surface of the conductive member 131 having the gear G2, and after engagement, the conductive member 131 having the gear G2 and the photosensitive drum 10 having the flange member 10A are aligned at the center and the outer peripheral surface. In the state
The drive pin 131A and the coupling 10C are fixed from the side of the photosensitive drum 10 using the set screw 51, and the flange member 10A and the gear G2 are connected and fixed.

When the image forming body drive motor (not shown) is started by the start of image formation, the rotational power of the drive gear G1 is transmitted to the photosensitive drum 10 via the coupling portion by the gear G2, and the photosensitive drum 10 is moved to the position shown in FIG. , And at the same time, application of a potential to the photosensitive drum 10 is started by the charging action of the Y scorotron charger 11.
After a potential is applied to the photosensitive drum 10, exposure by the first color signal, that is, an electric signal corresponding to Y image data is started in the Y exposure optical system 12, and the surface of the photosensitive drum 10 is rotated by the rotational scanning. An electrostatic latent image corresponding to the yellow (Y) image of the original image is formed on the photosensitive layer. This latent image is reversely developed in a non-contact state by the Y developing device 14, and a yellow (Y) toner image is formed on the photosensitive drum 10.

Next, the photoreceptor drum 10 places an M scorotron charger 11 on the yellow (Y) toner image.
A potential is applied by the charging action of the M exposure optical system 12
Exposure is performed using an electric signal corresponding to the second color signal of m, i.e., magenta (M) image data.
Yellow (Y) by non-contact reversal development
A toner image of magenta (M) is formed on the toner image of FIG.

By the same process, the cyan (C) toner image corresponding to the third color signal is further processed by the C scorotron charger 11, the exposure optical system 12 and the developing device 14, and the K scorotron charger 11. , Exposure optical system 1
A black (K) toner image corresponding to the fourth color signal is sequentially superimposed and formed by the second and developing units 14, and a color toner image is formed on the peripheral surface within one rotation of the photosensitive drum 10. You.

As described above, in this embodiment, Y, M,
The exposure of the organic photosensitive layer of the photoconductor drum 10 by the C and K exposure optical systems 12 is performed through a transparent substrate from the inside of the photoconductor drum 10. Therefore, the exposure of the image corresponding to the second, third, and fourth color signals can form an electrostatic latent image without being shielded by the previously formed toner image, which is preferable. Photoconductor drum 1
0 may be exposed from outside.

On the other hand, the recording paper P as a transfer material is sent out from a paper feed cassette 15 as a transfer material storage means by a feed roller (no code), fed by a feed roller (no code), and is fed by a timing roller. It is conveyed to 16.

The recording paper P is synchronized with the color toner image carried on the photosensitive drum 10 by the driving of the timing roller 16, and the recording paper P is charged by the paper charger 1 as paper charging means.
Due to the electrification of 50, the toner is attracted to the conveyor belt 14a and fed to the transfer area. The recording paper P, which is closely transported by the transport belt 14a, is moved around the photosensitive drum 10 by a transfer unit 14c as a transfer unit to which a voltage having a polarity opposite to that of the toner (positive polarity in the present embodiment) is applied in a transfer area. The color toner images on the surface are collectively transferred to the recording paper P.

The recording paper P on which the color toner image has been transferred is
The paper is discharged by a paper separation AC neutralizer 14h as a transfer material separating unit, separated from the transport belt 14a, and transported to the fixing device 17.

The fixing device 17 includes a heat ray fixing roller 17a as an upper roll-shaped heat ray fixing rotating member (upper fixing member) for fixing a color toner image, and a pressure rubber roller 47a as a lower fixing member. Is composed of
Inside the heat ray fixing roller 17a, a halogen lamp 171g that emits heat rays such as infrared rays or far infrared rays including visible light depending on a light source is provided as a heat ray irradiation unit.

Heat ray fixing roller 17a and pressure rubber roller 4
The recording paper P is sandwiched by a nip portion N formed between the recording paper P and the color toner image on the recording paper P by applying heat and pressure. Is discharged to the tray at the top of the device.

The toner remaining on the peripheral surface of the photosensitive drum 10 after the transfer is transferred to a cleaning blade 19 provided in a cleaning device 19 as an image forming body cleaning means.
Cleaning is performed by a. The photosensitive drum 10 from which the residual toner has been removed is uniformly charged by the scorotron charger 11, and enters the next image forming cycle.

Next, an embodiment of the developing device of the present invention used in the above-described image forming apparatus will be described with reference to FIG. FIG. 3 is an enlarged sectional view of the developing device of the present invention.
The arrows in FIG. 3 indicate the rotation direction of each roller, and the double arrows indicate the direction in which the developer is conveyed.

According to FIG. 3, the developing units 14 for each of the colors Y, M, C, and K are provided with the respective developing sleeves 141.
Are arranged clockwise in the order of Y, M, C and K, facing the photosensitive surface of the photosensitive drum 10 having an outer diameter of 100 mm, for example.

The developing device 14, which is a developing device for each color, contains the above-described two-component developers of yellow (Y), magenta (M), cyan (C) and black (K), respectively.
The developing sleeve 141 rotates in the opposite direction (clockwise direction in FIG. 3) to the rotational direction (clockwise direction in FIG. 3) of the photosensitive drum 10 at the developing position while maintaining a predetermined gap with respect to the peripheral surface of the photosensitive drum 10. It has.

The developing device 14, which is a developing device for each color, is configured as follows. In the developing device 14, reference numeral 140 denotes a developing device housing which is a developer accommodating portion for accommodating a two-component developer composed of toner and carrier; 142, a magnet roll which is a magnetic field generating means having fixed magnetic poles;
Reference numeral 143 denotes a developing sleeve which is a developer conveying body having a magnet roll 142 therein; 143, a layer thickness regulating member which is a layer thickness regulating means made of a magnetic material which regulates a developer layer thickness on the developing sleeve 141 to a predetermined amount; Is a developer receiving member made of a non-magnetic material; 148 is a developer removing plate having a magnet plate 148a on the back;
147 is a pair of stirring screws.

Developing sleeve 141 as a developer conveying member
Is, for example, an outer shape of 8 mm to 60 mm using a stainless steel material.
The rotation of the photosensitive drum 10 with a predetermined gap kept between the peripheral surface of the photosensitive drum 10 and the abutting rollers (not shown) provided at both ends of the developing sleeve 141. It is rotated in the opposite direction (clockwise rotation in FIG. 3) (clockwise rotation in FIG. 3). When the outer diameter is 8 mm or less, the magnetic poles N1, S1, N2, S2 required for image formation.
If the magnet roll 142 having at least five magnetic poles made of N3 cannot be formed, and the outer diameter of the developing sleeve 141 exceeds 60 mm, the developing device 1
4 increases in size. In particular, in a color printer having a plurality of sets of developing units 14 (see FIG. 1), the volume occupied by the developing device is increased, and the outer diameter of the photosensitive drum 10 is increased, or the size of the photosensitive drum 10 is increased. The forming apparatus becomes large.

The magnet roll 142 is included in the developing sleeve 141 and has a plurality of magnetic poles N1, N2, N3, S
1, S2 are alternately arranged, and are fixed concentrically with the developing sleeve 141, and apply a magnetic force to the peripheral surface of the non-magnetic sleeve.

A layer thickness regulating member 143 serving as a layer thickness regulating means.
Is made of, for example, a rod-shaped or plate-shaped magnetic stainless steel material which faces the magnetic pole N3 of the magnet roll 142 and is disposed at a predetermined gap from the developing sleeve 141.
The layer thickness of the two-component developer on the peripheral surface of 41 is regulated.

The receiving member 144 is made of a non-magnetic member using a resin member such as an ABS resin.
41 is disposed at a predetermined gap from the developing sleeve 141 on the downstream side in the rotation direction of the roller 41 and is adjacent to the end surface of the layer thickness regulating member 143, and is integrally formed by being fixed to the layer thickness regulating member 143 with an adhesive, for example. Further, the toner is prevented from spilling from the developer layer regulated by the layer thickness regulating member 143, and the developer layer of the two-component developer is stably kept on the peripheral surface of the developing sleeve 141. The receiving member 144 is the developing device housing 14.
0 and may be provided adjacent to the end face of the layer thickness regulating member 143.

The developer removing plate 148 is provided so as to face the magnetic pole N2 of the magnet roll 142.
The developer on the developing sleeve 141 is peeled off by the action of the repulsive magnetic field 3 and the magnet plate 148a provided on the back surface of the removing plate 148.

The transport supply roller 145 transports the developer peeled off by the removing plate 148 to the stirring screw 146, and supplies the developer stirred by the stirring screw 146 to the layer thickness regulating member 143. Reference numeral 145A is a blade provided on the transport / supply roller 145 for transporting the developer.

The agitating screws 146 and 147 rotate at a constant speed in directions opposite to each other, agitate and mix the toner and the magnetic carrier in the developing unit 14, and form a two-component developer containing a predetermined toner component uniformly. And

The toner and the carrier replenished into the developing device housing 140 from a toner replenishing port, which will be described later, which is opened on the top plate 140A above the developing device housing 140 above the stirring screw 147, move at a constant speed in directions opposite to each other. The rotating stirring screws 146 and 147 agitate and mix with the developer contained in the developing device housing 140 to form a developer having a uniform toner concentration, and the developer is rotated by the transporting supply roller 145 to control the layer thickness regulating member 143. Is transported to a predetermined thickness by the layer thickness regulating member 143, and the developer layer of the two-component developer is stably supplied onto the outer peripheral surface of the developing sleeve 141 by the receiving member 144. The developer that has developed the latent image on the photoreceptor drum 10 includes the repelling magnetic fields of the magnetic poles N2 and N3 and the magnet plate 14 provided on the back of the removing plate 148.
8a is peeled off by the action of
Is transported to the stirring screw 146 again. The electrostatic latent image on the photoconductor drum 10 has a direct current (DC) bias E1.
The reverse development is performed in a non-contact state by a non-contact development method by applying a developing bias voltage on which an alternating current (AC) bias AC1 is superimposed as necessary.

The developing device used in the image forming apparatus according to the present embodiment has an excellent feature that a non-contact developing method can easily perform development with a high image density without fog. To develop a clear image, it is desirable to use a two-component developer having the following particle diameter.

Conventionally, a two-component developer composed of a non-magnetic toner having an average particle diameter of tens of μm and a magnetic carrier having an average particle diameter of tens to hundreds of μm has been used in the developing device. However, as the developer used in the present invention, the transfer of the toner can be effectively controlled by the oscillating electric field. Therefore, the toner having an average particle diameter of 1 to 20 μm, preferably 4 to 10 μm, and the average particle diameter of 10 to 60 μm, More preferably, 20-50μ
m two-component developer is used.

The developing device 14 is supplied with the toner T and the carrier C. The supply of the toner T is performed by the toner concentration detection sensor 149 by the developing device housing 140.
When it is detected that the toner density in the inside has fallen below a predetermined toner density, the supply of the toner T is performed. Meanwhile, carrier C
In the case of (2), replenishment of a new carrier C is performed at appropriate times based on the integrated amount of the number of copies. The supplied toner is
The carrier C to be supplied from the hopper 200T, which is a supply unit of the toner T, and the hopper 200C, which is a supply unit of the carrier C, are supplied into the developing device 14 through the supply developer conveyance path 300. Replenishment developer transport path 3
A transport screw 300 </ b> A is provided inside 00, and the transport of the toner T or the carrier C is performed.

FIG. 4 shows the top plate 14 of the developing device 14 shown in FIG.
It is a top view which shows the conveyance screw part from which 0A was removed.

The agitating screws 146 and 147 provided as a pair of circulating means are meshed with gears G146 and G147 provided at their respective shaft ends, and are driven and rotated in opposite directions at a constant speed.

Between the stirring screws 146 and 147, partition plates 182 and 183 are installed in series in the axial direction, and the two-component developer D conveyed by the propulsive force of the stirring screw.
Is transported along the partition plate in the direction indicated by the arrow, and is circulated and transported in the developing device 14 through the openings 182A and 182B at the end portions of the partition plate.

In the top plate 140A, a supply port H (T · T) of the developer conveying path 300 that merges and conveys the toner T and the carrier C onto the surface located at the upstream end of the stirring screw 147 and conveys the toner. C) is open. With this arrangement, the newly supplied toner T or carrier C is sufficiently stirred in the circulating conveyance process by the stirring screws 146 and 147, and the supplied toner T is also charged by the stirring, and is transferred to the developing sleeve 141. And supplied.

The amount of toner T supplied from the hopper 200T is similar to the amount of toner T consumed by the development, but the amount of the carrier C supplied from the hopper 200C is not consumed. The amount of the developer inside increases. Correspondingly, the discharge port H (D) for discharging the excessively high level of the two-component developer D in the vicinity of the interface corresponding to the prescribed amount of the two-component developer D in the developing device housing 140 is provided. Is provided. The discharge port H (D) is a supply port H (TC) at the end face of the stirring screw 146 on the downstream side of the conveyance.
And a water wheel-shaped impeller 400A that rotates and scoops up the two-component developer D near the interface and sends it into the discharge port H (D) at the opening end face of the discharge port H (D).
Is provided. In the circulating transport path formed by the stirring screws 146 and 147, the positional relationship between the discharge port and the supply port is such that the discharge port H (D) is located at the upstream portion, and then the supply port H between the toner T and the carrier C. (TC) is located, and the newly supplied toner T and carrier C are not immediately discharged from the discharge port H (D). At the discharge port H (D), the impeller 400A rotates so as to be picked up near the interface of the two-component developer D and fed toward the opening, and floats on the interface together with the developer slightly deteriorated in the development. The dust such as paper dust that exists in the form of dust is provided by providing the discharge port H (D) near the interface and at the end face in the circulation path where dust easily collects.
Debris will be removed very efficiently.

Each of the image forming apparatuses of the present invention has a developing device 1
4 is supplied independently of the carrier C and the toner T, but the carrier path is shared and the carrier C is also supplied with the toner T.
Is also supplied to the developing device 14 through the same developer conveying path 300. The present invention rationalizes and simplifies the method of supplying the carrier C and the toner T, and supplies the toner T to the developer conveying path 300.
And the carrier C is supplied to the developing device 14 without stagnation.

(Embodiment 1) In the image forming apparatus of the present embodiment, a carrier C from a hopper 200C serving as a carrier storage unit receives a carrier screw 300A serving as toner supply means from a toner reservoir of a hopper 200T serving as a toner storage unit.
And the hopper 200T is provided with a stirring means, and the carrier C supplied by stirring by the stirring means moves downward due to its large mass and is supplied preferentially to the toner supply means. It has become. 5A and 5B show a cross section of the developer supply section 200 (A) of the present embodiment, where FIG. 5A is a side cross section, FIG. 5B is an AA cross section, and FIG.
It shows a cross section.

As shown in the figure, a conveying screw 300A as toner supply means is provided at the lower end of the hopper 200T which is a storage section for the toner T, and the toner T inside the hopper 200T is rotated by the rotation of the conveying screw 300A.
Is transported to the developer transport path 300.

In this embodiment, a hopper 200C for accommodating the carrier C is provided inside the hopper 200T. The supply roller 201 is provided at the lower end of the hopper 200C.
C, and a fixed amount of the carrier C is supplied onto the toner T in the hopper 200T for each rotation of the supply roller 201C. A toner agitating roller 201T is provided between the hopper 200C and the transport screw 300A, and the carrier C becomes the toner T by the rotation of the agitating roller 201T.
Although the carrier C has a larger mass than the toner T, the carrier C drops in the toner T during the stirring process, reaches the transport screw 300A quickly, and enters the developer transport path 300. Is conveyed.

When the toner concentration detecting sensor 149 detects that the toner concentration in the developing device housing 140 has become lower than a predetermined toner concentration, the control unit rotates the transport screw 300A to transfer the toner T in the hopper 200T to the developing device. Supply into housing 140. On the other hand, a predetermined amount of the carrier C is supplied based on the integrated amount of the number of prints and the like. For example, supply roller 20 for every 100 prints
1C is controlled so as to rotate at a preset predetermined number of revolutions or a predetermined time, and a preset supply amount of the carrier C is discharged into the hopper 200T. Hopper 200T
The carrier C supplied into the developing device housing 140 is rapidly mixed and dropped in the toner T by the rotation of the stirring roller 201T, and is supplied into the developing device housing 140 together with the toner T in a carrier C rich state by the rotating transport screw 300A. Done.

By performing the above-described control, the supplied toner T and carrier C are supplied without staying in the developer transport path 300, and 50,000 prints are performed without replacing the developer by a service person. As described above, an image forming apparatus capable of continuously obtaining a good developed image is provided.

Note that the plural sets of developing devices 14 shown in FIG.
Is provided with the developer supply section 200 (A) for each developing device, but the hopper 200T
6 are stored in the hoppers 200T of the respective developer supply units 200 (A). However, since the carrier C is common, color toners of Y, M, C, and K are stored. As shown in a perspective view of the developer supply unit 200 (B), a hopper 200T as a plurality of toner storage units
And a hopper 200C, which is a common carrier accommodating portion, are integrally provided, and a plurality of developing devices of a color printer are provided with toner T.
And the carrier C are supplied respectively, so that the supply means is simplified.

(Embodiment 2) In the image forming apparatus of this embodiment, a hopper 200T as a toner storage and a hopper 200C as a carrier storage are arranged in parallel, and the carrier C from the hopper 200C supplies toner. The toner is supplied to the developing device 14 together with the toner T by supplying the toner to the transport screw 300A. FIG. 7 shows a cross section of the developer supply section 200 (E) of the present embodiment,
(A) shows a side section, and (b) shows an EE section.

As shown in the figure, a transport screw 300A as a toner supply means is provided at the lower end of the hopper 200T for storing the toner T.
The toner T inside the hopper 200T is transported to the developer transport path 300 by the rotation of 0A.

In the present embodiment, a hopper 200C for accommodating the carrier C is provided in parallel with the hopper 200T. A screw 20 is provided at the lower end of the hopper 200C.
2C, the carrier C in the hopper 200C is discharged into the hopper 200T by the rotation of the screw 202C. The discharge position of this carrier C is
Since the toner T is located at the most upstream position in the transport direction of the toner T due to the rotation of the transport screw 300A just above 00A,
The carrier C discharged from the hopper 200C is transported together with the toner T by the transport screw 300A to the developer transport path 30.
In this case, the carrier C is preferentially conveyed.

When the toner density detecting sensor 149 detects that the toner density in the developing device housing 140 has fallen below a predetermined toner density, the control unit rotates the transport screw 300A to transfer the toner T in the hopper 200T to the developing device. Supply into housing 140. On the other hand, a predetermined amount of the carrier C is supplied based on the integrated amount of the number of prints and the like. For example, screw 20 for every 100 prints
2C is controlled to rotate at a preset predetermined number of revolutions or a predetermined time, and a preset supply amount of the carrier C is discharged into the hopper 200T. Hopper 200T
The carrier C supplied to the inside is rotated by a transport screw 3
00A is supplied together with the toner T into the developing device housing 140 in a carrier C rich state.

By performing the above-described control, the supplied toner T and carrier C are supplied without staying in the developer conveying path 300, and 50,000 prints can be performed without replacing the developer by a service person. As described above, an image forming apparatus capable of continuously obtaining a good developed image is provided.

The plural sets of developing devices 14 shown in FIG.
Is provided with the developer supply section 200 (E) for each developing device, but the hopper 200T
The toner T in each of the four color toners of Y, M, C, and K is 200T of the developer supply unit 200 (E).
Since the carrier C is common, a plurality of hoppers 200T and a common hopper 200C are integrally provided as shown in a perspective view of the developer supply unit 200 (F) in FIG. A configuration in which the toner T and the carrier C are respectively supplied to a plurality of developing devices of a color printer is also performed, so that the supply unit is simplified.

(Embodiment 3) In the image forming apparatus of this embodiment, a hopper 200T as a toner storage and a hopper 200C as a carrier storage are arranged in parallel, and a common supply means to the developing device 14 is provided. The supply means is provided with an opening / closing means capable of selectively opening one of the hoppers 200T and 200C, and the carrier C discharged by the opening operation is mixed with the toner T. It is configured to be sent to the supply means. FIG. 9 shows the developer supply section 200 (G) of the present embodiment, and (a)
2 is a perspective view, and FIG. 2B is a cross-sectional view of a shutter portion as an opening / closing means.

As shown in the figure, a hopper 200T for storing adjacent toner T and a hopper 20T for storing carrier C
A common conveying screw 300A is provided at the lower end of 0C, and the lower end of the hopper 200T or the hopper 200C is opened by turning the shutter 300B, which is an opening / closing member, to the right or left, and the conveying screw 300A The toner T or the carrier C discharged by the opening operation by the rotation is supplied to the developing device 14 through the developer conveying path 300.

In the image forming apparatus of the present embodiment, a small amount of the carrier C is supplied simultaneously when supplying the toner T, and a small amount of the toner T is supplied simultaneously when supplying the carrier C. Control as shown in the block diagram of FIG. 10 is performed by turning the shutter 300B right and left. It is desirable that a small amount of toner T is mixed in the hopper 200C in addition to the carrier C.

When the toner density detecting sensor 149 detects that the toner density in the developing device housing 140 has fallen below a predetermined toner density, the control unit operates the shutter 300.
Opening and closing of shutter by reciprocation of B and conveying screw 300
A rotates, and the toner T is supplied together with the carrier C into the developing device housing 140 in a toner T rich state. On the other hand, a predetermined amount of the carrier C is supplied based on the integrated amount of the number of prints and the like. For example, every 100 prints, the control unit opens and closes the shutter by reciprocating the shutter 300B and rotates the transport screw 300A. A predetermined amount of the carrier C is supplied together with the toner T into the developing device housing 140 in a carrier C rich state. .

By performing the above-described control, the supplied toner T and carrier C are supplied without staying in the developer conveying path 300, and 50,000 prints are performed without replacing the developer by a service person. As described above, an image forming apparatus capable of continuously obtaining a good developed image is provided.

Although the developer supply section described in the first to third embodiments has an excellent effect when applied to the developing device of the color printer shown in FIG. 1, the tandem type color image forming apparatus shown in FIG. A similar effect can be obtained even if the present invention is applied to the developing device 14 described above. Therefore, such a tandem type color image forming apparatus will be described. The same reference numerals are used for members having the same functions as those in FIG. 1.

The color image forming apparatus shown in FIG. 11 is a tandem type color image forming apparatus in which a plurality of image forming bodies are arranged in parallel, and the configuration and function are as follows. At the periphery of the transfer belt 14a, which is an intermediate transfer member, four sets of process units 100 including yellow (Y), magenta (M), cyan (C), and black (K) are provided. The single-color Y, M, C, K toner images formed by the transfer belt 14a
The transferred color toner images are transferred in a lump on a recording sheet as a transfer material, fixed, and discharged outside the apparatus.

Reference numeral 10 denotes a photosensitive drum as an image forming body for each color, 11 a scorotron charger as charging means for each color, 12 an exposure optical system as image writing means for each color, and 1
Reference numeral 4 denotes a developing device for each color, and reference numeral 190 denotes a cleaning device that is a cleaning unit for the photosensitive drum 10 for each color.

The photosensitive drum 10 as an image forming body for each color
Is formed by forming an organic photoreceptor layer (OPC) having an overcoat layer (protective layer) on the outer periphery of a cylindrical metal substrate formed of, for example, an aluminum material on the outer periphery of the metal substrate. As will be described later, the transfer belt 14a in the contact state is driven to rotate by receiving the driving force from the transfer belt 14a, and the photosensitive drum 10 of each color is rotated in the direction indicated by the arrow in the figure while being grounded. Rotated.

The organic photoreceptor layer is composed of a charge generation material (CGM)
And a charge transport layer (CTL) containing a charge transport material (CTM) as a main component. The organic photoreceptor layer comprises a charge generation material (CGM) and a charge transport material (C
(TM) in a single layer, and the photosensitive layer having the single-layer structure or the two-layer structure usually contains a binder resin.

The scorotron charger 11, which is a charging means for each color, has the same polarity as the toner (toner at the time of development) used by the control grid and the corona discharge electrode maintained at a predetermined potential. The charging action (minus charging in the present embodiment) is performed by the corona discharge of (negative polarity), and a uniform potential is applied to the photosensitive drum 10. As the corona discharge electrode of the scorotron charger 11, a saw-tooth electrode or a needle electrode can also be used.

Exposure optical system 1 as image writing means for each color
2 indicates that the exposure position on the photosensitive drum 10 is the photosensitive drum 1 with respect to the scorotron charger 11 for each color described above.
It is arranged around the photosensitive drum 10 so as to be located on the downstream side in the rotation direction of 0. The exposure optical system 12 performs image exposure on the photosensitive layer of the photosensitive drum 10 in accordance with image data of each color read by a separate image reading device and stored in a memory, and forms an electrostatic latent image on the photosensitive drum 10 for each color. Form an image.

The developing device 14, which is a developing means for each color,
As described with reference to FIG. 3, a predetermined gap is maintained with respect to the peripheral surface of the photoconductor drum 10, and the photoconductor drum 10 rotates in a forward direction with respect to the rotation direction of the photoconductor drum 10. It has a cylindrical developing sleeve 141 made of a non-magnetic stainless steel or aluminum material of 25 mm, and has yellow (Y), magenta (M), cyan (C) and black (K) inside according to the developing color of each color. Of a two-component developer. The developing device 14 is arranged at a predetermined gap from the photosensitive drum 10 by an abutting roller (not shown).
It is kept in a non-contact state with a gap of 500 μm, and by applying a developing bias in which a DC voltage and an AC voltage are superimposed on the developing sleeve 141, the developer carried on the peripheral surface is brought into a standing state to make contact development. The photosensitive drum 1
A toner image is formed on 0.

For the developing device 14 as a developing means, conventionally, a two-component developer composed of a non-magnetic toner having an average particle diameter of tens of μm and a magnetic carrier having an average particle diameter of tens to hundreds of μm is used. I have. However, when the developer is used for non-contact development, the transfer of the toner can be effectively controlled by the oscillating electric field. Therefore, the toner having an average particle diameter of 1 to 20 μm, preferably 4 to 10 μm and the average particle diameter of 10 to 10 μm are used. A two-component developer comprising a carrier of 60 μm, more preferably 20 to 50 μm is used.

The photosensitive drum 10 uniformly charged by the scorotron charger 11 is subjected to image exposure by the exposure optical system 12 to form an electrostatic latent image, and is developed by the developing device 14 to form a toner image. It is formed. This toner image is transferred onto a transfer belt 14a described later at a transfer position. Cleaning device 1 that electrostatically collects transfer residual toner remaining on the drum after transfer is completed.
90 cleans.

Process unit 1 for four colors of Y, M, C and K
The transfer belt 14a in which 00 is opposed in parallel is an endless belt having a volume resistivity of 10 ¹² to 10 ¹⁵ Ω · cm. A conductive material is dispersed in an engineering plastic such as a 0.1 to 1.0 mm thick semiconductive film substrate, and a fluorine coating having a thickness of 5 to 50 μm is preferably performed as a toner filming prevention layer, This is a seamless belt having a two-layer structure. Transfer belt 1
In addition to the above, a base material 4a having a thickness of 0.5 to 2.0 in which a conductive material is dispersed in silicon rubber or urethane rubber or the like is used.
mm semi-conductive rubber belts can also be used. The transfer belt 14a includes a driving roller 14d, a driven roller 14
e, tension roller 14k and backup roller 1
At the time of image formation, the drive roller 14d is rotated by a drive motor (not shown), and is exposed by a pressing elastic plate 14b disposed upstream of a transfer position for each color. The transfer belt 14a is pressed against the body drum 10, and the transfer belt 14a is rotated in the direction shown by the arrow in the figure. At this time, the photosensitive drum 10 is driven to rotate by receiving the driving force of the transfer belt 14a following the movement of the transfer belt 14a.

The primary transfer unit 14c as a transfer unit for each color
Is preferably constituted by a corona discharger, is provided opposite to the photosensitive drum 10 for each color with the transfer belt 14a interposed therebetween, and the transfer belt 14a and the photosensitive drum 1 for each color are provided.
A transfer area (no sign) is formed for each color between 0 and 0. A DC voltage having a polarity opposite to that of the toner (positive polarity in the present embodiment) is applied to the primary transfer device 14c for each color, and a transfer electric field is formed in the transfer area. The toner image is transferred onto the transfer belt 14a.

The static eliminator 14m, which is a static eliminator for each color,
Preferably, the primary transfer unit 1 is constituted by a corona discharger.
The transfer belt 14a charged by 4c is neutralized.

Pressing elastic plate 1 serving as a pressing means of the transfer belt
4b is formed by a rubber blade of urethane or the like, is disposed upstream of the transfer position for each color, presses the transfer belt 14a against the photosensitive drum 10 at the time of image formation, and follows the movement of the transfer belt 14a to move the photosensitive belt. The body drum 10 is rotated.

The image forming unit 1 of black (K) is started by starting a photoconductor drive motor (not shown) by starting image recording.
The photoconductor drum 10 is rotated in the direction indicated by the arrow in the figure, and at the same time, the application of a potential to the K photoconductor drum 10 is started by the charging action of the K scorotron charger 11.

After a potential is applied to the K photosensitive drum 10, image writing is started by the K exposure optical system 12 using a first color signal, that is, an electrical signal corresponding to K image data, and the K photosensitive drum 10 is exposed. K of the original image on the surface of the body drum 10
An electrostatic latent image corresponding to the image is formed.

The latent image is subjected to reversal development in a contact state by the K developing device 14, and a black (K) toner image is formed in accordance with the rotation of the K photosensitive drum 10.

The K toner image formed on the K photoreceptor drum 10 as the image forming body by the above-described image forming process is transferred to the K transfer area (no symbol) in the K transfer area (no symbol). The transfer belt 1 is moved by the primary transfer device 14c.
4a.

Next, the transfer belt 14a is synchronized with the C toner image, and the cyan (C) image forming unit 10
By 0, a potential is applied by the charging action of the C scorotron charger 11, and the C exposure optical system 12 performs image writing with a second color signal, that is, an electric signal corresponding to C image data, and develops C. By the reversal development of the contact by the device 14, the C toner image on the C photosensitive drum 10 is transferred by the C primary transfer device 14c, which is the first transfer means, in the C transfer area (no reference numeral). A C toner image is formed on top of the K toner image.

By the same process, the image is synchronized with the K and C superposed toner images, and is formed by the third color signal formed on the M photosensitive drum 10 by the magenta (M) image forming unit 100. M corresponding to M image data
Is the first in the M transfer area (no sign).
The M primary transfer unit 14c, which is a transfer unit, forms an M toner image on top of the K and C toner images, and further synchronizes with the K, C, and M superposed toner images. Taken, yellow (Y) image forming unit 100
The Y toner image formed on the Y photosensitive drum 10 corresponding to the Y image data based on the fourth color signal by
In the Y transfer area (no symbol), the Y primary transfer unit 14c, which is the first transfer unit, forms the Y toner image on the K, C, and M toner images in a superimposed manner. A superposed color toner image of K, C, M and Y is formed on the transfer belt 14a.

The transfer residual toner remaining on the peripheral surface of the photosensitive drum 10 for each color after the transfer is cleaned by a cleaning device 190 which is a means for cleaning the image forming body for each color.

In synchronization with the formation of the superimposed color toner image on the transfer belt 14a, the recording paper P is transferred from the paper supply cassette 15 as the transfer material storage means via the timing roller 16 as the transfer material supply means to the second transfer. The transfer belt 14 is conveyed to a transfer area (no symbol) of a secondary transfer device 14g, which is a unit, and is applied with a DC voltage having a polarity opposite to that of the toner (positive polarity in the present embodiment).
The superimposed color toner images on a are collectively transferred onto the recording paper P.

The recording paper P on which the color toner image has been transferred is
The charge is removed by a charge removing electrode 16b, which is a separating means formed of a sawtooth electrode plate, conveyed to the fixing device 17, and heat and pressure are applied between the fixing roller 17a and the pressure roller 17b, so that the recording paper P After the toner image is fixed,
It is discharged to a tray outside the device.

The transfer residual toner remaining on the peripheral surface of the transfer belt 14a after the transfer is cleaned by a cleaning device 190a which is a transfer belt cleaning means provided opposite to the driven roller 14e with the transfer belt 14a interposed therebetween. .

The developing device 14, which is a developing means for each color,
The above-described two-component developers of yellow (Y), magenta (M), cyan (C), and black (K) are accommodated respectively, and each is kept at a predetermined gap with respect to the peripheral surface of the photosensitive drum 10 and developed. The developing sleeve 141 rotates in the rotation direction of the photosensitive drum 10 at the position.

The developing device 14, which is a developing means for each color,
The configuration is the same as that described with reference to FIG. 3, and the developer supply units 200 (A),
00 (B), 200 (E), 200 (F), 200
By controlling the toner T and the carrier C to be supplied into the developing device housing 140 through any one of (G) and the developer transport path 300, the supplied toner T and the carrier C are transferred to the developer transporter 300. An image forming apparatus is provided which is supplied without staying in the path 300 and continuously obtains a good developed image for 50,000 prints or more without replacing the developer by a service person.

[0103]

According to the image forming apparatus of the present invention in which the carrier and the toner are independently supplied to the developing device, the supply route and the supplying method of the developer are simplified, and the two-component developer in the developing device is new. With the toner level and capacity level always maintained properly while the carrier is being replenished, a developing device that can continuously exhibit high developing performance is realized. An image forming apparatus has been provided in which a high-quality image can be obtained for a long time without requiring replacement.

[Brief description of the drawings]

FIG. 1 is a cross-sectional configuration diagram of an image forming apparatus including a developing device of the present invention.

FIG. 2 is a cross-sectional configuration diagram of an image forming body.

FIG. 3 is an enlarged sectional view of the developing device.

FIG. 4 is a sectional view of a main part of the developing device.

FIG. 5 is a cross-sectional view of a developer supply unit (Embodiment 1).

FIG. 6 is a perspective view of a developer supply unit (Embodiment 1).

FIG. 7 is a cross-sectional view of a developer supply unit (Embodiment 2).

FIG. 8 is a perspective view of a developer supply unit (Embodiment 2).

FIG. 9 is a perspective view and a sectional view of a main part of a developer supply unit (Embodiment 3).

FIG. 10 is a block diagram of developer supply (Embodiment 3).

FIG. 11 is a cross-sectional configuration diagram of a color image forming apparatus including the developing device of the present invention.

[Explanation of symbols]

Reference Signs List 10 photoconductor drum 11 scorotron charger 12 exposure optical system 14 developing device (apparatus) 15 paper feed cassette 17 fixing device 140 developing device housing 141 developing sleeve 142 magnet roll 145 transport / supply roller 146,147 stirring screw 149 toner density detection sensor T Toner C carrier 200 (A), 200 (B), 200 (E), 200
(F), 200 (G) developer supply section 200T (toner) hopper 200C (carrier) hopper 300 (supply) developer transport path 300A transport screw

Continued on the front page F term (reference) 2H030 BB23 BB38 2H077 AA12 AA15 AA18 AA25 AA39 AB02 AB18 AC02 AC04 AC16 AD06 AD13 AD32 AD36 BA07 CA02 DA10 DA22 DA35 DB01 EA03 EA16 GA13 GA17

Claims (8)

[Claims] A developing device having a two-component developer including a toner and a carrier is supplied with toner from a toner storing portion and a carrier from a carrier storing portion, and the developer is collected from the developing device. The image forming apparatus according to claim 1, wherein the carrier is supplied to the toner supply means from above the toner reservoir in the toner storage section. 2. The image forming apparatus according to claim 1, wherein the toner storage unit has a stirring unit, and the supplied carrier is moved downward by stirring. 3. A developing device having a two-component developer composed of a toner and a carrier is supplied with a toner from a toner storing portion and a carrier from a carrier storing portion, and the developer is collected from the developing device. The image forming apparatus according to claim 1, wherein the toner accommodating section and the carrier accommodating section are arranged in parallel, and the carrier is supplied to a toner supply unit and supplied to the developing device together with the toner. Forming equipment. 4. The image forming apparatus according to claim 3, wherein the carrier accommodating section is arranged upstream of the toner supply unit. 5. The image forming apparatus according to claim 1, wherein the storage section includes a plurality of toner storage sections and a common carrier storage section, and supplies the toner to a plurality of developing devices provided in the image forming apparatus.
5. The image forming apparatus according to claim 4. 6. A developing device having a two-component developer composed of a toner and a carrier is supplied with toner from a toner storing portion and carrier from a carrier storing portion, and the developer is collected from the developing device. In the image forming apparatus, the toner accommodating section and the carrier accommodating section are arranged in parallel and have a common supply unit to the developing device. An image forming apparatus provided in a storage unit. 7. The image forming apparatus according to claim 6, wherein the carrier is mixed with the toner and sent to the supply unit. 8. The image forming apparatus according to claim 6, wherein the carrier accommodated in the carrier accommodating portion is mixed with a toner.