JP2003015420A - Developing device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To save serviceman's trouble and to prolong an interval to visit to do service by a system realizing the prolongation of the life of developer and the life of a developing system and restraining toner scattering from a developing unit in a developing device in an image forming device. SOLUTION: In the two-component developing device in the image forming device, the two-component developer is automatically exchanged in a main body, and the developing device is equipped with an aperture part for relieving internal pressure in the developing unit and has an exhaust duct 108 for exhausting to the outside of the image forming device. Furthermore, the duct 108 passes through a waste developer container 72 for discharging the used developer in a two-component developer exchanging means, and the container 72 is provided with a toner filter 73.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention utilizes electrophotography or an electrostatic recording method, and is used for developing a latent image formed on an image bearing member to visualize the latent image, or a developing device for developing the latent image. And an image forming apparatus using the same.

[0002]

2. Description of the Related Art Conventionally, a method has been adopted in which a deteriorated developer which has reached the end of its durable life is replaced with a new developer by a service person at the time of regular maintenance. Therefore, the developer life is a factor that determines the service maintenance interval. Although the development of a developer that extends the durable life and a process that does not deteriorate the developer are being carried out as the target, the current life of the developer is actually 30,000 to 50,000 sheets.

Therefore, there has been proposed a device capable of suppressing the deterioration of the charging performance by supplying the developer to the developing device. As such a device, for example, in Japanese Patent Publication No. 2-21519, a developer in the developing device which has become excessive due to replenishment of new developer or carrier in the developing device is discharged to a waste developer container and collected. A so-called trickle developing type is proposed.

As an example of the developing device used therein, a developing device used in a conventional image forming apparatus is shown in FIG.

The inside of the developing container 48 is divided into a developing chamber (first chamber) 53 and a stirring chamber (second chamber) 54 by a partition wall 46 extending in a direction perpendicular to the plane of the drawing, and an upper portion of the partition wall 46. Is open. In the developing chamber 53 and the stirring chamber 54,
A two-component developer containing a non-magnetic toner and a magnetic carrier is accommodated, and the developer that has become excessive in the developing chamber 53 is collected in the stirring chamber 54 side.

In the developing chamber 53 and the agitating chamber 54, first and second agitating screws 51 and 52 are disposed as developer agitating / conveying means, respectively. The first agitating screw 51 agitates and conveys the developer in the developing chamber 53, and the second agitating screw 52 controls the developer from a toner replenishing tank (not shown) under the control of the developer concentration controller. The toner supplied to the upstream side of the stirring screw 52 and the developer already in the stirring chamber 54 are stirred and conveyed,
Make the toner density uniform. The partition wall 46 includes a developing chamber 53 and a stirring chamber 54 at the front and rear end portions in FIG.
There is provided a developer passage (not shown) that allows the developer and the developer to be communicated with each other.
It is configured to move from one passage of the partition wall 46 into the stirring chamber 54 by the conveying force of 2.

The developing chamber 53 of the developing device 49 has an opening at a portion facing the photosensitive drum 2, and the developing sleeve 43 is rotatably disposed so that the developing sleeve 43 is partially exposed at the opening. The developing sleeve 43 is made of a non-magnetic material, and rotates in the arrow direction in the drawing during the developing operation. Inside the developing sleeve 43, a magnet (magnet roller) 50 as a magnetic field generating means is fixed. The developer in the developing chamber 53 is supplied to the developing sleeve 43 by the stirring screw 51.
And is carried on the surface of the developing sleeve 43 in the state of a magnetic brush by the magnetic force of the magnet roller 50. The developer carried on the developing sleeve 43 is conveyed to the developing area facing the photosensitive drum 2 by the rotation of the developing sleeve 43. During the transportation, the developer on the developing sleeve 43 is regulated by the developer returning member 41 and the blade 42, and the amount of the developer transported to the developing area is appropriately maintained.

The developer conveyed to the developing area is used for developing the latent image formed on the photosensitive drum 2. Development efficiency,
That is, in order to improve the toner application rate to the latent image,
To the developing sleeve 43, a developing bias voltage obtained by superimposing an AC voltage on a DC voltage is applied from a power source 55.

To explain further, the magnet roller 50 in the developing sleeve 43 has a five-pole structure, and the magnetic force of the conveying magnetic pole (pumping pole) S2 causes the stirring screw 5 to move.
The developer supplied by No. 1 is constrained on the surface of the developing sleeve 43, held and carried, and conveyed to the developer reservoir 45 by the rotation of the developing sleeve 43. The amount of the developer is regulated by the developer return member 41, and a magnetic pole for conveyance (cut pole) N2 having a magnetic flux density higher than a certain level necessary for stable restraint.
Thus, the developer is sufficiently restrained on the surface of the developing sleeve 43 to form a magnetic brush. Next, by cutting the magnetic brush with the blade 42, the developer amount is further regulated to an appropriate amount, and the developer is conveyed to the magnetic pole S for conveyance.
At 1, the sheet is conveyed toward the developing area.

Next, in the developing area, a DC voltage and / or an alternating voltage obtained by superimposing an AC voltage thereon is applied as a developing bias from the bias power source 55 to the developing sleeve 43 while the magnetic brush of the developer is formed by the developing pole N1. Then, the toner in the magnetic brush is transferred onto the photosensitive drum 2, and the toner is attached to the latent image on the photosensitive drum 2 to develop it.
The latent image is visualized as a toner image.

The developer not consumed for the development is taken into the developing container 48 at the taking-in section A by the rotation of the developing sleeve 43 and is collected. In the take-in portion A, the conveyed developer tries to enter into the developing container through the gap between the developer sleeve 43 and the developing container 48 (taking-in portion 100) together with air, but at this time, the internal pressure in the developing container rises. As a result, the air that was about to be transported together with the developer in the intake section 100 does not enter the developing container,
Blow out. The toner released from the carrier scatters with the blowing air. If the developer is scattered outside the developing container, it may stain the inside of the copying machine or stain the optical sensor or the like, which may cause a malfunction.

As a method of reducing the scattering at the intake portion, an electrode member 60 is provided in the intake portion A of the developing container surrounding the outside of the developing sleeve 43, and a voltage having the same polarity as the toner is applied to release the toner. A conventional method is to draw the non-magnetic toner to the developing sleeve 43 side, attach it to the magnetic carrier there, and take it into the developing container. However, as the image forming speed has become faster in recent years, the developing sleeve has become faster in rotation speed,
Since the internal pressure in the developing container 43 is more likely to rise, the conventional method as described above cannot sufficiently suppress the scattering. Further, in order to obtain a high-definition image, it has been attempted to reduce the particle size of the toner, but many small particle size toners have a small binding force to the carrier, and it is difficult to suppress the scattering. .

Therefore, in order to further reduce the scattering, there is a method of suppressing the scattering by providing a pressure relief hole in the developing device and closing the pressure relief hole in the filter that allows the passage of air. It is disclosed in Japanese Patent No. 39861. this is,
By allowing the air to pass through the mesh through which the toner does not pass, the internal pressure inside the developing device is prevented from rising and the toner does not leak.

[0014]

However, if a filter is simply provided, it is good at the initial stage, but if it is used for a long period of time, the filter will be clogged with toner and air will not be able to pass through, so pressure release is not possible. Since there was a problem that it disappeared and the effect disappeared, it took time and labor for a service person or the like to replace the filter. In particular, when there are a plurality of developing devices, it is necessary to perform maintenance for each developing device.

In view of the above technical problems, the present invention has an object of simplifying maintenance and reducing the number of passages by a service person by connecting a filter to a waste developer container.

[0016]

The structure of the present invention will be further described. A developing container containing a two-component developer composed of toner particles and magnetic particles and a two-component developer contained in the developer container are agitated. And a rotatably provided developer carrier for carrying and carrying the developer carried by the carrying means in the developing area.
An image forming apparatus for automatically exchanging component developers in a main body, comprising a developing device provided in the developing container and having an opening for releasing pressure in a developing device, and sucking air in the vicinity of the opening. However, the exhaust duct has a duct for exhausting to the outside of the image forming apparatus, and the exhaust duct passes through a waste developer container for storing the spent developer in the two-component developer automatic exchanging means, and the waste developer container has a toner filter. Is configured to have.

Further, when the suction method is used to release the pressure of the developing device, in order to prevent the toner from leaking out of the main body machine, the opening is closed by a magnet arranged in the developer positive opening. A magnetic brush is preferably formed to seal leakage of developer through the opening. More preferably, these openings are provided near the developer transport means. Further, the image forming apparatus has a structure in which air is easily evacuated at the opening and a seal for leaking a small amount of toner is provided, a toner filter is provided at the exhaust port of the duct, and air is exhausted through the filter. good.

As described above, the developing container has the opening for releasing the internal pressure in the developing device, and the image forming apparatus is provided with the duct for exhausting the air in the vicinity of the opening to the outside of the image forming apparatus. In addition, the internal pressure inside the developer container is less likely to increase, scattering can be reduced, and maintenance is facilitated by providing a toner filter on the waste developer container along the return path leading to the exhaust duct. Even if the amount of toner becomes a little large, the maintenance interval can be extended by collecting the toner in the container. In particular, in an image forming apparatus having a plurality of developing devices, instead of performing maintenance on all the developing devices,
All that is required is maintenance of the waste developer container.

Furthermore, if a suction fan is provided, not only does the internal pressure in the developing container become high, but also by making the inside of the developing device a negative pressure, the scattering can be further reduced. This is because the negative pressure in the developing container increases the flow of air in the intake part in the direction of being taken into the developing container together with the developer, and the toner that is likely to scatter is also sucked into the developing container and becomes a developer. This is because when they are mixed, they adhere to the carrier again.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a developing device according to the present invention will be described below with reference to the accompanying drawings. In addition,
This developing device is used, for example, in an image forming device as described below, but is not necessarily limited to this form.

(First Embodiment) FIG. 1 shows a full-color copying machine according to the first embodiment of the present invention.

In FIG. 1, each YMCK station forms a yellow, magenta, cyan, and black image of a full-color image. In the following description, for example, if there is a primary charger 21, the primary chargers 21Y, 21M, 21C and 2 in each YMCK station will be described.
Refers to 1K. Image formation is performed in each station as follows. First, a photosensitive drum 4 as an image carrier is rotatably provided, the photosensitive drum 4 is uniformly charged by a primary charger 21, and then an information signal is exposed by a light emitting element 22 such as a laser to be statically charged. An electrostatic latent image is formed and visualized by the developing device 9. Next, the visible image is transferred by the transfer charger 23 onto the transfer paper (not shown) carried by the transfer paper carrying sheet 27.

At each station, a yellow toner image, a magenta toner image, a cyan toner image, and a black toner image are sequentially transferred and superposed on the transfer paper. The transfer paper on which the toner images of the four colors are laminated is mixed and fixed by heat and pressure by the fixing device 25, and is discharged outside the device as a full-color image. Further, the transfer residual toner on the photosensitive drum 4 is removed by the cleaning device 26.

On the other hand, in FIG. 1, reference numeral 26 denotes a magnetic brush roller device which is rotatably supported by the rotating mechanism (not shown) with respect to the photosensitive drum 2 as an image carrier. A cleaning device using this magnetic brush roller device 26 is arranged such that the magnetic brush roller device 26 is located downstream of a cleaning blade 27 for scraping residual toner, as shown in the schematic sectional view of FIG. 2 has an opening on the side opposite to 2, and a magnet roller 31 is disposed in this opening. The magnet roller 31 is surrounded by a non-magnetic material such as aluminum, stainless steel or titanium steel. A sleeve 32 is formed, and magnetic particles 33, which are carriers, are held on the surface of the sleeve 27 to form ears.

The magnetic brush roller device 26 rotates in the forward direction with respect to the rotation direction of the photosensitive drum 2, and the magnetic particles 33
When the ears are formed on the surface of the photosensitive drum 2 as the image carrier, a bias voltage is applied to the ears by a bias applying unit (not shown), and the corona product adhered to the surface of the photosensitive drum 2. And talc are removed.

As the photosensitive layer on the surface of the photosensitive drum as the image carrier, α-Se, CdS, ZnO ₂ , OPC, α-
Although various known materials such as Si can be used, they are particularly effective when the present invention is applied to an OPC photoreceptor having low mechanical strength. Although not shown in the present embodiment, a DC bias of AC superposition is applied between the sleeve 32 of the magnetic brush roller device 26 and the photosensitive drum 2.

By applying an AC bias by the bias applying means for the magnetic brush roller device 26,
In the gap between the surface of the photosensitive drum 2 and the surface of the developer carrying member such as a sleeve carrying the developer of the developing device, the reciprocating motion of the developer occurs, and compared with the case where the developer is just in contact and running.
The electric field increases the force with which the developer strikes the surface of the photosensitive drum.

Next, a description of the developing container 4 of this embodiment will be given with reference to FIG.
Will be explained.

In the figure, the developing device 4 arranged to face the photosensitive drum 2 includes a developing container 48, a developing sleeve 43 as a developer conveying means, and a developer returning member 41 for regulating a developer collecting portion 45. , And a blade 42 as a developer height controlling member. The inside of the developing device 4 has a developing chamber (first chamber) 5 by a partition wall 46 extending in the vertical direction.
3 and the stirring chamber (second chamber) 54, and the upper portion of the partition wall 46 is open.

The developing chamber 53 and the agitating chamber 54 contain a two-component developer containing a non-magnetic toner and a magnetic carrier, and the excess developer in the developing chamber 53 is collected on the agitating chamber 54 side. .

The developing device is provided with an opening 101, and in this embodiment, the developing device 4 is provided with a developing container 4 through the opening 101.
A ventilation path 107 through which the depressurized air passes from the developing container opening 101 to the developing device upper opening 106 along the wall of FIG.
Are formed.

Further, in the developing device of FIG. 4 of the present embodiment, the pressure releasing opening 101 and the developing container opening 101 from the opening along the wall of the developing container 8 to the developing device upper opening 10 are provided.
Up to 6, a ventilation path 107 through which the depressurized air passes is formed, and on the other hand, the image forming apparatus of this embodiment is also provided with an exhaust duct 108 for guiding the air in the vicinity of the upper opening 106 of the developing device to the outside of the machine. Has been. Further, the upper opening 1 of the developing device
06 and the exhaust duct 108 of the main body are tightly fitted to each other so that there is no leakage in the main body.

Next, the operation of the developing device will be described. The developing device 4 imparts tribo by agitating the two-component developer 32 with the screws A and B, and the developer is conveyed to the developing sleeve 33 which is a developing carrier. After that, it is pumped up to the developing sleeve by the N3 pole shown in FIG.
The N1 pole conveys the toner to the developing main pole S1. In the developing section, the bias applying means 34 is used to
Development is promoted by applying a DC bias of AC superposition between the photosensitive drum 2 and the photosensitive drum 2. The carrier is preferably magnetic particles. The magnetic particles have a particle size of 30 to 100.
μm, preferably 40 to 80 μm, and an electric resistance value of 1
A resin-coated magnetic carrier in which ferrite particles (maximum magnetization 60 emu / g) are resin-coated so as to have a resistance of 0 ⁷ Ωcm or more, preferably 10 ⁸ Ωcm or more, more preferably 10 ⁹ to 10 ¹⁴ Ωcm is preferably used.

The measurement of the resistance value of magnetic particles (for example, resin-coated ferrite particles) was carried out with a measuring electrode area of 4 cm ² .
Using a sandwich type cell with an interelectrode gap of 0.4 cm, a voltage of 1 kg was applied to one of the electrodes and an applied voltage E (V / cm) was applied between the two electrodes to generate magnetic particles from the current flowing in the circuit. Is a value obtained by measuring the resistance value of. Further, in the present invention, the toner having an average particle diameter of 7.5 μm is used, but the toner preferably has an average particle diameter of 6 to 9 μm.

After that, the developer is stripped off at the repelling pole between N2 and N3, and again stirred by the screw and pumped up. It is considered that by repeating this stirring operation, the toner and the external additive adhere to the surface of the magnetic carrier to reduce the tribo imparting ability.

Therefore, the life of the magnetic carrier of the two-component developer is usually 50,000 sheets / 500 g, because the tribo-imparting ability is lowered along with the durability. Therefore, 1000 g of developer is required to double the maintenance interval, for example. Therefore, in the first embodiment, as shown in FIG. 3, a cartridge-type replaceable member (hereinafter referred to as a carrier box) 71 in which only the magnetic carrier 500g is stored in advance is provided above the developing device 4.

Next, the automatic developer replacement sequence will be described with reference to the timing chart shown in FIG.

In this embodiment, the number of copy processes is defined. This value counts how many copies have been made up to the present after replenishing the magnetic carrier from the carrier box. In this embodiment, the number is 1000.

First, when image formation is started, the number of copies taken this time is added to the number of copy processes described above. Since 1 copy is considered here, 1 is added. Next, the required toner amount is measured and replenished on the photosensitive drum during development. At this time, it is determined whether or not the number of copy processes exceeds 1000, and if the conditions are not satisfied, the image formation is ended in the normal sequence. However, if the conditions are satisfied, 10 g of the magnetic carrier is replenished from the carrier box into the developing device after the development on the photosensitive drum, and the magnetic carrier is replenished, so that the copy processing number is reset to zero.

However, since the amount of the developer in the developing device increases by 10 g in this state, the developer is filled in the developing device and the developer overflows if this control is repeated. Therefore, after the above-mentioned sequence is activated and the carrier is replenished, the fog removing potential (= charging potential-developing DC bias potential) is lowered by 200 V with respect to the normal set value. That is, in the image forming apparatus, the fog-removing potential is normally −100V, whereas the charging potential or the developing DC bias potential is changed to −300V. Then, the magnetic carrier and the reverse toner, which are positive components on the developing sleeve, are developed and adhere to the photosensitive drum.

In this embodiment, in order to deposit 10 g of the magnetic carrier on the photosensitive drum, the fog removing potential is set to -30.
It was set to 0 V and required for 10 seconds. After that, the magnetic carrier attached on the photosensitive drum is sent to the cleaner by the rotation of the photosensitive drum. It is collected by a magnetic brush provided in the cleaner. After the magnetic carrier is recovered, it can be reused by acting as a magnetic brush cleaner.

However, if it is left as it is, the magnetic carrier is gradually accumulated in the mag roller. Therefore, as shown in FIG. 2, a member 30 for regulating the amount of magnetic carriers of the magnetic brush formed on the mag roller is provided. With this configuration, more magnetic carrier than necessary is conveyed from the cleaner to the waste developer recovery container 72 (not shown).

On the other hand, the waste developer container 72 is provided with the toner filter 73 and the partition wall 74, and by opening the partition wall 74, the toner dropped on the 74 is collected in the waste developer container 72.

By doing so, when the waste developer container 72 is replaced or collected, the toner filter can be replaced all at once, and when the toner is accumulated on the toner filter so as to be clogged, the toner is self-weighted. Since it falls on the partition wall, the toner filter replacement timing can be extended. Further, even in the case of a plurality of developing devices, only one filter is required, and the developing device does not require maintenance of the developing device such as agent replacement and handling of scattering.

(Second Embodiment) The developing container 4 of this embodiment will be described with reference to FIG. The developing device of this embodiment (FIG. 6) has an opening for depressurizing and a developing container 8 through the opening.
An air passage 107 through which the depressurized air passes is formed from the developing container opening 101 to the developing device upper opening 106 along the wall of the developing device, and the developing device upper opening 106 is also formed in the image forming apparatus of this embodiment. An exhaust duct 108 for guiding the air in the vicinity to the outside of the machine is provided, and a ventilation fan 109 for sucking the air in the vicinity of the upper opening 106 of the developing device and discharging it to the outside of the machine is provided at an exhaust port 110 of the duct 108. Although not provided in the filter in the opening of the developing device (FIG. 6), the magnet 103 is provided around the opening 101.
1 is arranged so as to surround 1. Part of the developer is attracted to and retained by the magnet while the developer is conveyed from the replenishment port side (front side) to the back side, so that the opening of the developer is closed (magnetic brush). 102) is formed.

In FIG. 3, on the side wall surface of the agitation chamber 14, a pressure release opening 101 having a diameter of 5 mm is provided at a position where the developer comes into contact when the upper surface of the developer corrugates when being conveyed by the agitation screw 12. Are arranged, and a brush of the developer (magnetic brush 102) is formed so as to close the opening to prevent the developer and the toner from leaking.

When a new developing device is used, the developing device is put in the developing device, and then the developing device is tilted so that the developing material is attached to the magnet 103 so that the magnetic brush 102 completely closes the opening. It is preferable to use it later.

As described above, in the structure in which the opening is sealed by the magnetic brush 102 formed of the developer, since the air near the developing device upper opening 106 is sucked by the blower fan 109, the air pressure near the developing device upper opening 106 is increased. Becomes low and air escapes from the gap of the magnetic brush, so that the air in the developing container is drawn out from the developing container opening 101. Therefore, the internal pressure in the developing device does not rise, and the scattering of the intake portion hardly occurs.

Further, since the filter as in the previous embodiment is not used, there is no problem such as filter damage or clogging.

Since the opening is provided in the vicinity of the developer conveying means, the magnetic brush 102 is sometimes moved when the flow of the developer conveyed by the stirring means comes into contact with or hits the magnetic brush 102, Toner attached to the magnetic brush does not increase excessively during long-term use. That is,
Toner excessively adhered to the magnetic brush has a weak adhesive force. Therefore, when the magnetic brush moves, the toner falls and is mixed again with the developer conveyed by the stirring means. Further, the carrier forming the magnetic brush also partly replaces the carried developer when it comes into contact with the carried developer. Therefore, it becomes possible to prevent the internal pressure in the developing device from rising for a longer period of time, and to prevent the scattering.

Furthermore, to prevent the toner from leaking out of the machine,
A toner filter 74 is prepared in the air passage.

Further, the waste developer container 72 is provided with the toner filter 73 and the partition 74, and when the suction duct is not sucking, the toner dropped on the 74 by opening the partition 74 is collected in the waste developer container 72. To be configured.

By doing so, when the waste developer container 72 is replaced or collected, the toner filter can be replaced all at once, and when the toner is accumulated on the toner filter so as to be clogged, the toner is self-weighted. Since it falls on the partition wall, the toner filter replacement timing can be extended.

Also, in the case of a plurality of developing devices, only one filter is required, and the developing device does not require maintenance of the developing device such as agent replacement and handling of scattering.

(Third Embodiment) In the previous embodiment, when the magnetic brush is formed so that the density of the magnetic brush is high, a large amount of toner leaks from the opening through the gap of the magnetic brush. The example developing device (FIG. 7) uses a magnet 112 so that the density of the magnetic brush 111 becomes sparse to some extent.
Was placed. In such a configuration, the opening 101
Since the air is good, the air is more sucked from the opening 101, and the inside of the developing device has a negative pressure. If a negative pressure is reached, as described in the previous embodiment, the scattering of the intake portion can be further reduced.

When the magnetic brush 111 is made sparse, the toner easily leaks from the opening 101. However, in the image forming apparatus of this configuration, even if some toner leaks from the opening 101, the suction port of the duct is not formed. It does not pollute the inside of the aircraft because it is pulled into. Further, since a dustproof filter (not shown) is arranged at the discharge port 110 and the air is exhausted to the outside of the image forming apparatus through the filter, the toner does not scatter to the outside of the apparatus.

That is, by making the inside of the developing device a negative pressure,
The scattering inside the machine can be further reduced, and the leakage of toner from the opening is prevented from being discharged to the outside of the machine by the filter of the discharge port.The shape of the opening and the magnet attached to the opening are The shape is not limited to the illustrated shape, and various shapes can be used by the designer as desired. Also, a method of forming a magnetic brush by arranging a magnet and a magnetic member along the peripheral surface of the opening may be used.
By doing so, it is easy to form a magnetic brush most suitable for the shape and size of the opening. The magnetic member is preferably made of a ferromagnetic material such as an iron plate, a nickel plate, a cobalt plate, or a plate made of an alloy thereof.

By doing so, when the waste developer container 72 is replaced or collected, the toner filter can be replaced all at once, and when the toner is accumulated on the toner filter so as to be clogged, the toner is self-weighted. Since it falls on the partition wall, the toner filter replacement timing can be extended. Further, even in the case of a plurality of developing devices, only one filter is required, and the developing device does not require maintenance of the developing device such as agent replacement and handling of scattering.

[0059]

As described above, the developer container for accommodating the two-component developer composed of toner particles and magnetic particles, and the developer conveying for agitating the two-component developer contained in the developer container. And an rotatably provided developer carrier for carrying and carrying the developer carried by the carrying means in the developing area, and performing the automatic exchange of the two-component developer in the main body. In the developing container, provided with a developing device having an opening for releasing the pressure in the developing device, and an exhaust duct for exhausting the air in the developing device from the opening to the outside of the image forming apparatus, This exhaust duct passes through the waste developer container that stores the spent developer in the two-component developer automatic exchange means, and the waste developer container has a toner filter, thereby extending the life of the developer and the longevity of the developing system. To achieve reduction, and it is possible to suppress toner scattering from the developing device.

[Brief description of drawings]

FIG. 1 is an image forming apparatus of the present invention.

FIG. 2 Cleaning device of the present invention

FIG. 3 is a developing device of the present invention.

FIG. 4 is a developing device according to the first embodiment.

FIG. 5 is a sequence diagram of automatic developer exchange according to the present invention.

FIG. 6 is a developing device according to a second embodiment.

FIG. 7 is a developing device according to a third embodiment.

[Explanation of symbols]

2 photosensitive drum 4 Developing device 9 Development device 21 Primary charger 22 Light emitting element 23 Transfer charger 25 Fixing device 26 Cleaning device 27 Transfer sheet transport sheet

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tomoyuki Sakamaki             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Jun Mochizuki             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Motohide Shiozawa             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F-term (reference) 2H027 DA45 DE07 DE09 EA06 EC06                       ED10 HB02 HB07 HB12 HB13                 2H077 AA02 AB02 AC02 AC16 AD06                       AD13 AD32 AD36 CA01 CA15                       CA16 CA19 DA12 DA22 DA47                       DA87 DB01 EA03 EA16 GA04                       GA13

Claims (13)

[Claims] 1. A developer container for containing a two-component developer composed of toner particles and magnetic particles, and a developer transport means for transporting the two-component developer contained in the developer container while stirring.
In the image forming apparatus, which has a rotatably provided developer carrying member for carrying and carrying the developer carried by the carrying means in a developing region, wherein the two-component developer is automatically exchanged in the main body. This developing duct has a developing device provided in the developing container and having an opening for releasing the pressure in the developing device, and an exhaust duct for exhausting the air in the developing device to the outside of the image forming apparatus through the opening. The image forming apparatus is characterized in that it passes through a waste developer container for storing the used agent in the two-component developer automatic changing means and has a toner filter in the waste developer container. 2. The image forming apparatus according to claim 1, wherein the developing device has a ventilation path from the opening to a vicinity of an exhaust port of the duct of the image forming apparatus in the apparatus. 3. A developer container containing a two-component developer composed of toner particles and magnetic particles, and a developer transport means for transporting the two-component developer contained in the developer container while stirring.
In the image forming apparatus, which has a rotatably provided developer carrying member for carrying and carrying the developer carried by the carrying means in a developing region, wherein the two-component developer is automatically exchanged in the main body. The developing device is provided in the developing container and has an opening for releasing the pressure in the developing device, and has an exhaust duct for sucking air near the opening and exhausting it to the outside of the image forming apparatus. An image forming apparatus, wherein the duct passes through a waste developer container for storing the used developer in the two-component developer automatic changing means, and the waste developer container has a toner filter. 4. The image forming apparatus according to claim 3, wherein the developing device has a ventilation path from the opening to a vicinity of an exhaust port of the duct of the image forming apparatus in the apparatus. 5. The developing device according to claim 3, wherein a filter is provided at the opening of the developing container so as to close the opening, and leakage of the developer from the opening is sealed. . 6. A developing device in which a filter is provided in the opening of the developing container so as to close the opening, and leakage of the developer from the opening is sealed is used. The image forming apparatus according to item 1. 7. A magnetic brush is formed so as to close the opening by a magnet or a magnet and a magnetic member arranged in the vicinity of the opening, and leakage of the developer from the opening is sealed. Item 5. The developing device according to Item 3 or 4. 8. A magnet or a magnet and a magnetic member arranged in the vicinity of the opening forms a magnetic brush so as to close the opening, thereby sealing the leakage of the developer from the opening. The image forming apparatus according to Item 3 or 4. 9. The image according to claim 3, wherein a toner filter is provided in the exhaust duct, and a developing device for exhausting the toner to the outside of the machine through the filter is used. Forming equipment. 10. A developing device in which an opening for releasing the internal pressure in the developing device is provided in the vicinity of the developer transporting means of a developing container is used.
The image forming apparatus according to item. 11. The image forming apparatus according to claim 1, wherein the two-component developer that is automatically exchanged is a magnetic carrier and a toner. 12. The image according to claim 11, wherein the two-component developer to be exchanged is prepared in a cartridge arranged above the developing means and is replenished in the developing machine at a constant interval. Forming equipment. 13. The image forming apparatus according to claim 12, wherein the replenishment interval is determined by the number of durable sheets.