JP3452108B2 - Developer supply device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a facsimile, a printer, etc.
The present invention relates to a developing device that develops a latent image formed on a latent image carrier using a two-component developer including a carrier and a toner.

[0002]

2. Description of the Related Art Conventionally, as a method of developing an electrostatic latent image using toner, a two-component developer composed of a toner and magnetic particles, represented by a magnetic brush developing method (see, for example, US Pat. No. 2,870,403). A two-component developing method and a one-component developing method using (hereinafter referred to as a developer) are known.

As a developing device adopting the above-mentioned two-component developing method, there is known a developing device provided with a developer agitating and conveying member for agitating and conveying a developer for uniformizing toner concentration and controlling toner charging. There is. According to this developing device, when the developer is replaced, the developer agitating / conveying member can be driven to collect the used developer at a predetermined collecting position.

In the two-component developing method, the toner is held on the surface of the magnetic particles by the electrostatic force generated by the friction between the relatively large magnetic particles and the minute toner.
When the developer carrying member carrying the developer and the latent image carrying member having the electrostatic latent image formed on the surface thereof are opposed to each other, the electric field formed by the electrostatic latent image causes the toner to move toward the electrostatic latent image with respect to the toner. The attraction force overcomes the binding force between the toner and the magnetic particles, and the toner is attracted and attached onto the electrostatic latent image to visualize the electrostatic latent image. This developer is repeatedly used while replenishing the toner consumed by the development. Therefore,
In this two-component developing method, it is necessary to keep the mixing ratio (toner concentration) of magnetic particles and toner constant in order to obtain a stable image density. For this reason, it is necessary to install a toner replenishing mechanism, a toner concentration sensor, etc., which makes the developing device large and its operating mechanism complicated.

Therefore, from the viewpoint of downsizing and cost reduction of the developing device, the amount of developer to be accommodated is set small, and a complicated toner concentration control mechanism is provided by the developer stirring / conveying member and the toner concentration sensor. Instead, a developing device that controls the toner density and the toner charge amount has been proposed. For example, in Japanese Examined Patent Publication No. 5-67233, a magnetic particle layer is formed on a developer carrier in a container, and a toner supply unit in the container accommodates toner so as to come into contact with the magnetic particle layer. The toner particles are taken into the magnetic particle layer at the toner supply unit by the movement of the magnetic particles in the magnetic particle layer in accordance with the rotation of the developer carrier, and the developer in which the toner and the magnetic particles are mixed is moved in the rotational direction of the developer carrier. The toner is circulated in a developer circulation region formed on the upstream side of the developer regulating member to charge the toner, and the developer regulating member regulates the layer thickness to convey the toner to the developing region. According to this
It is possible to provide a small-sized and inexpensive developing device that can sufficiently charge toner without stabilizing the developer agitating / conveying member and a complicated toner concentration control mechanism and can generally stabilize the toner concentration.

Among the developing devices adopting the above-mentioned conventional two-component developing method, a developing device which does not use a developer stirring / conveying member, a toner concentration control mechanism, or the like, depends on the start of use of a new product or the life of the developer. In order to be able to convey the new developer to the development area evenly after the replacement of the developer, it is necessary to set the developer as uniformly as possible to the part corresponding to the development area when replacing the developer. Was complicated.

For example, in the developing device disclosed in Japanese Patent Laid-Open No. 63-4282, in order to set the developer uniformly in the axial direction of the developing sleeve, the developing device is started at a position where the magnetic force of the magnet built in the developing sleeve does not reach. Provide a developer storage room,
The start developer is stored in this storage chamber in advance and sealed with a seal member, and when the developing unit is mounted on the main body of the copying machine, the developing sleeve is manually rolled in the rotation direction or rocked in the sleeve axial direction. The developer is sent to a region where it can be carried by the developing sleeve by peeling off the seal member after the above. Further, in the developing device disclosed in JP-A-3-158871, a conductive coil is provided in the developer accommodating portion, and the magnetic field is intermittently changed to make the developer balance uniform.
Further, in the developing device of Japanese Patent Application No. 7-119340 proposed by the present applicant, the developer accommodating chamber is configured to be detachable from the main body of the developing device, and before the developer accommodating chamber is attached to the developing main body. In advance, the developer balance in the storage chamber is made uniform.

[0008]

As described above, in the conventional developing device, since it is necessary to set the developer uniformly in the axial direction of the developing sleeve, the operability at the time of mounting the main body is reduced. It was bad, and there was room for improvement in terms of productivity and maintainability. Further, in the one in which the mechanism for uniformly setting the developer is provided in the developing device, there are problems that the structure is complicated, the cost becomes high, and the device becomes large.

The present invention has been made in view of the above problems, and a first object is to apply to a developing device which does not require a complicated toner density control mechanism and the like, and to simplify the structure of the developing device. An object of the present invention is to provide a developer supply device that achieves cost reduction and space saving, and that improves productivity, maintainability, and user operability.

A second object of the present invention is to provide a developer supply device which prevents the developer from overflowing from the longitudinal end of the developer carrying member.

A third object of the present invention is to provide a developer supply device capable of suppressing fluctuations in the supply amount of the developer.

A fourth object is to provide a developer supplying device capable of stably and more uniformly setting the developer on the developer carrying member.

[0013]

In order to achieve the above-mentioned object, the invention of claim 1 has a developer carrier carrying a developer comprising toner and magnetic particles on its surface, and a developer carrier contained therein. Magnetic field generating means, a developer regulating member that regulates the amount of the developer carried on the developer carrying member, and a developer retaining portion of a predetermined volume in which the developer regulated by the developer regulating member retains. , to a developing device including a toner accommodating portion having a toner supply opening adjacent the upstream of the developer conveyance direction on the developer carrier to the developer residence portion, opposite to the developer carrying member, a developing A developer supplying device for supplying a developer from outside the device prior to shipment of the developing device, the developer storing means storing the developer, and a slit along the longitudinal direction of the developer carrying member. And the agent supply port configured to be openable and closable. And it is characterized in that the developer stored in the developer storage unit and is supplied to the surface of the developer carrier from the agent supply opening.

According to a second aspect of the present invention, in the first aspect of the invention, the width in the longitudinal direction of the agent supply port is set so as not to exceed the carrying width of the developer on the developer carrying member. To do.

According to a third aspect of the present invention, in the first or second aspect of the invention, the agent supply port is provided with a guide means for guiding the developer in the agent supply direction by surface movement. .

According to a fourth aspect of the present invention, in the first or second aspect of the invention, when the developer is supplied to the surface of the developer carrying member, the developer supply port faces the developer carrying member, and The feature is that they are arranged close to each other.

According to a fifth aspect of the present invention, in the third aspect, a magnetic field generating means is provided inside the guide means, and the magnetic field generating means is provided while the developer is guided in the developer supply direction by the guide means. It is characterized in that the developer is captured by the magnetic force of.

According to a sixth aspect of the invention, in the fifth aspect of the invention, after the developer is discharged from the developer supply port, the developer is captured by the magnetic force of the magnetic field generating means included in the developer carrier. It is characterized by doing so.

According to the first aspect of the present invention, the developer stored in the developer storing means is supplied to the surface of the developer carrier through the slit-shaped agent supply port,
The developer can be uniformly set on the image carrier with the required amount.

According to the second aspect of the present invention, the width in the longitudinal direction of the agent supply port does not exceed the carrying width of the developer on the developer carrier, so that the developer supplied on the developer carrier is It is set within the carrying width.

According to the third aspect of the invention, the developer is forcibly conveyed toward the agent supply port as the surface of the guide means moves.

According to the fourth aspect of the invention, at the time of supplying the developer, the developer which has passed through the developer supply port which is arranged facing and close to the developer carrying member is formed in a slit shape. It is supplied to the developer carrying member without retaining while maintaining the distribution of the developer when passing through the mouth.

According to the invention of claim 5, the developer is captured by the magnetic force of the magnetic field generating means contained in the guide means,
It is forcibly conveyed toward the agent supply port with the movement of the surface of the guide means.

According to the invention of claim 6, the developer supplied onto the developer carrier is captured by the magnetic force of the magnetic field generating means contained in the developer carrier, and is carried on the surface of the developer carrier. To be done.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which the present invention is applied to a developing device used in an electrophotographic copying machine (hereinafter referred to as a copying machine) which is an image forming apparatus will be described below.
FIG. 1 is a partial cross-sectional view showing a schematic configuration of a developing device and a developer supplying hopper according to the embodiment, and shows a state in which the developing device is on a production line (the same applies to subsequent drawings). . In the developing device 100, a support case 10 having an opening 10a formed toward a photoconductor drum (not shown) serving as an image carrier, a part of which is exposed from the opening 10a,
A developing sleeve 5 as a developer carrying member carrying a developer 2 composed of magnetic particles (hereinafter referred to as carrier) and toner on its surface, and magnetic poles (P1 to P4) fixedly arranged inside the developing sleeve 5 as magnetic field generating means. A magnet roller 6, a doctor 7 as a developer regulating member for regulating the amount of developer carried on the surface of the developing sleeve 5, and a space for accommodating the developer staying above the developing sleeve 5. It is provided with a sheet 8 to be formed, a toner hopper 11 as a toner storage portion, and the like. In FIG. 1, the magnetic force lines of the magnetic poles (P1 to P4) of the magnet roller 6 and their directions are shown. In this embodiment, P1 and P3 are the N pole and P
2, P4 is the south pole.

A part of the histograph 8 extends along the developing sleeve 5 with the developing sleeve 5 at a predetermined interval, and a projection 9 as a predoctor is formed at the end thereof. Then, when the developing sleeve 5 is rotationally driven in the direction of the arrow between the region surrounded by the doctor 7 and the protrusion 9 and the developing sleeve 5, the developing sleeve 5 is supplied to a developing position at a portion facing a photosensitive drum (not shown). A developer retaining portion A is formed in which the developer whose progress is blocked by the doctor 7 is retained. Further, the toner hopper 11 has a toner replenishing port 11a adjacent to the upstream side of the developer retaining portion A in the developer conveying direction and facing the surface of the developing sleeve 5, and a space adjacent to the toner replenishing port 11a is provided. A toner agitator 12 is provided for sending toner (not shown) to the toner supply port 11a while stirring.

The operation of controlling the toner density in the developing device 100 having the above structure will be described below. When the developing device 100 is set in the main body of the copying machine, the toner agitator 12 causes the toner supply port 1
The toner (not shown) supplied to the developing sleeve 5 via 1a is taken into the carrier of the developer existing only in the developer retaining portion A. The developer carried on the developing sleeve 5 is conveyed as the sleeve 5 rotates in the direction of the arrow, and is regulated by the doctor 7 to form a thin layer. The thinned developer is conveyed to a developing area that faces a photoconductor drum (not shown) that is arranged to face the developing sleeve 5. Then, in this developing area, toner is supplied to the electrostatic latent image formed on the photoconductor drum (not shown) to form a visible image. At this time, the developer not involved in the visualization of the image is conveyed along with the rotation of the developing sleeve 5, and after taking in new toner supplied from the toner agitator 12 and supplied from the toner supply port 11a, Return to the developer retention section A.

On the other hand, a part of the developer, which is not supplied to the developing area and is blocked by the doctor 7, goes toward the toner replenishing port 11a of the toner hopper 11 by the internal pressure and gravity of the developer itself in the developer retaining portion A. To move. Then, the developer that has moved to the vicinity of the toner supply port 11a is conveyed so as to circulate to the doctor 7 side as the developing sleeve 5 rotates.

When the toner is successively taken into the toner hopper 11 as the developer circulates, the toner concentration in the developer retaining portion A rises and the bulk of the developer increases, so that the developer on the developing sleeve 5 increases. The developer that accompanies the sleeve swells so as to block the toner supply port 11a. In this way, as the toner supply port 11a becomes narrower, the amount of toner taken into the carrier decreases, and finally the toner supply port 11a is blocked by the swollen developer and the toner cannot be taken in.
The toner concentration in the developer is always kept below a certain concentration.

As described above, the developing device 10 having the above structure
At 0, the toner supply is suppressed due to an increase in the bulk of the developer (increases as the toner concentration increases), and as a result, the toner concentration of the developer conveyed to the developing area is self-controlled. Whether the developer can be uniformly set in the axial direction of the developing sleeve 5 when the developing device is shipped from the factory and actually attached to the copying machine main body depends on whether the toner density after that is set. Determine uniformity and toner density control level. In the conventional developing device, various contrivances have been made in order to set the developer uniformly in the axial direction of the developing sleeve, but as described above, there are problems in each. Therefore, in the present embodiment, in order to set the developer uniformly, a developer supply hopper described later is provided on the production line, and the developer is supplied from the hopper to the development sleeve 5, so that the development sleeve 5 The necessary amount of developer is preliminarily carried on the top. Hereinafter, the first to sixth embodiments will be described.

[First Embodiment] The configuration of the first embodiment will be described with reference to FIG. In FIG. 1, a developer supply hopper 1 for supplying the developer to the developing sleeve 5 is arranged above the opening 10 a of the support case 10. The developer supply hopper 1 includes a hopper body 1a as a developer storage unit that stores the developer 2, and a developer supply port 4 that can be opened and closed. A shutter unit 3 for allowing or limiting the passage of the developer 2 from the supply port 4 is disposed near the agent supply port 4. This shutter unit 3
It is configured to operate in the direction of the arrow in the figure, and in the figure, the solid line indicates the open position and the broken line indicates the closed position. The operation of the shutter section 3 is controlled by a drive mechanism (not shown).

The agent supply port 4 is formed in a slit shape along the longitudinal direction of the developing sleeve 5, as shown in FIG. 2 corresponding to the plan view of the main part of FIG. The width of the slit in the longitudinal direction is set to be equal to the carrying width of the developer on the developing sleeve 5. Further, the width in the direction orthogonal to the longitudinal direction (short side direction) is configured to be uniform along the longitudinal direction. In the figure, reference numeral 14 is a side seal for regulating the carrying width of the developer on the developing sleeve 5.

The amount of the developer 2 supplied from the agent supply port 4 can be controlled by the supply time when the flow rate per unit time is constant. Further, when the flow rate is not constant, it is possible to integrate and manage the measured values by a flow meter (not shown) installed inside. However, the supply amount of the developer may be managed by another method. For example,
As shown in FIG. 1, when the level sensor 13 is provided on the side surface of the hopper body 1a, the level sensor 13 can be obtained by subtracting the amount set in the hopper. For example, a prescribed amount of developer is set in the hopper, and the amount of consumption when the powder surface of the developer is detected by the level sensor 13 is measured. Then, after the supply of the developer set to the prescribed amount is started, the supply of the developer is stopped when the powder surface of the developer is detected by the level sensor 13, so that the developing sleeve 5 is developed by the consumption amount. The agent can be supplied. As the level sensor 13, for example, an optical sensor or a piezoelectric sensor can be used.

According to the developer supplying hopper 1 and the developing device 100 configured as described above, while the developing sleeve 5 is rotationally driven in the arrow direction, the developer 2 is supplied from the developer supplying port 4 of the developer supplying hopper 1. Is supplied, the developer 2 is captured by the magnetic force generated by the magnet roller 6 contained in the developing sleeve 5, and is set on the surface of the developing sleeve 5. Here, since the developer supply port 4 of the developer supply hopper 1 is formed in a slit shape along the longitudinal direction of the developing sleeve 5, the developer 2 supplied from the developer supply port 4 is
The developing sleeve 5 is set uniformly along the longitudinal direction. Moreover, since the supply amount of the developer 2 can be controlled by opening and closing the shutter portion, it is possible to set the necessary amount on the developing sleeve 5. (Hereafter, margin)

As described above, since the developer is already uniformly set on the developing sleeve 5 when the developing device is shipped, a mechanism for uniformly setting the developer in the axial direction of the developing sleeve 5 is provided. Since it is not necessary to provide it in the developing device, the structure of the developing device can be simplified, the cost can be reduced, and the space can be saved. Further, when the developing device is attached to the main body of the copying machine, it is not necessary to send the developer to an area where it can be conveyed by the developing sleeve, and before the toner hopper is attached to the developing main body, the developer in the hopper is beforehand Since it is not necessary to make the balance uniform, it is possible to improve productivity, maintainability, and user operability. Furthermore, since the width of the slit in the longitudinal direction is set to be equal to the carrying width of the developer on the developing sleeve 5, the developer may be excessively supplied to the end portion of the sleeve 5 in the longitudinal direction. , And is set within the carrying width on the sleeve. Therefore, the uniformity of the developer in the longitudinal direction of the developing sleeve 5 can be maintained, and the developer can be prevented from overflowing without being carried at the end portion in the longitudinal direction of the developing sleeve 5.

[Second Embodiment] FIG. 3 is a partial sectional view showing a schematic structure of a developing device and a developer supplying hopper according to a second embodiment. However, the configuration of the developing device 100 is the same as that in FIG. In the second embodiment, the developer supply hopper 110 is arranged at the position of the developer supply hopper 1 shown in FIG. The developer supplying hopper 110 is a hopper body 110 as a developer storing means for storing the developer 2.
a, an agent supply port 114 configured to be openable and closable, and an agent supply roller 115 as guide means for guiding the developer 2 in the agent supply direction by rotation.

In the vicinity of the agent supply port 114, the supply port 11
A shutter portion 113 for allowing or restricting the passage of the developer 2 from the nozzle 4 is provided. This shutter unit 113
Is configured to operate in the direction of the arrow in the figure,
In the figure, the solid line indicates the open position and the broken line indicates the closed position. The operation of the shutter section 113 is controlled by a drive mechanism (not shown). Also, the agent supply port 114
Is formed in a slit shape along the longitudinal direction of the developing sleeve 5, as in the first embodiment. Further, the agent supply roller 115 is composed of a roller member having a length similar to that of the developing sleeve 5, and is rotationally driven in the arrow direction at a constant speed by a drive mechanism (not shown). The agent supply roller 115 is preferably made of a non-magnetic member, but at least the surface may be made of a non-magnetic member. However, the material of the roller is not limited to the non-magnetic member.

According to the developer supply hopper 110 having the above-described structure, the developer 2 is forcibly conveyed toward the agent supply port 114 as the agent supply roller 115 rotates, so that the developer flows. Even when the property is poor, fluctuations in the agent supply amount in the width direction or changes over time (hereinafter simply referred to as fluctuations) are suppressed, and the agent supply amount per unit time can be made stable and uniform. . In this way, the supply amount of the developer per unit time can be made stable and uniform, so that the agent supply amount control accuracy can be further improved as compared with the configuration of the first embodiment.

In the second embodiment, the agent supply roller 11 is used as a guide means for guiding the developer 2 in the agent supply direction.
Although the example in which No. 5 is provided has been shown, any member other than the roller may be used as long as the developer can be guided in the agent supply direction by surface movement. For example, a belt member which is stretched between a plurality of rollers and whose surface moves endlessly may be used.

[Third Embodiment] FIG. 4 is a partial sectional view showing a schematic structure of a developing device and a developer supplying hopper according to the third embodiment. However, the configuration of the developing device 100 is the same as that in FIG. In the third embodiment, the developer supply hopper 120 is arranged at the position of the developer supply hopper 1 shown in FIG. The developer supplying hopper 120 is a hopper body 120 as a developer storing means for storing the developer 2.
a and an agent supply port 124 configured to be openable and closable.

In the vicinity of the agent supply port 124, the supply port 12
A shutter portion 123 for allowing or restricting the passage of the developer 2 from the sheet 4 is provided. This shutter section 123
Is configured to operate in the direction of the arrow in the figure,
In the figure, the solid line indicates the open position and the broken line indicates the closed position. The operation of the shutter section 123 is controlled by a drive mechanism (not shown). Further, the agent supply port 124 is formed in a slit shape along the longitudinal direction of the developing sleeve 5 as in the first embodiment. In particular, this third embodiment
In the above configuration, the direction of the agent supply port 124 faces the developing sleeve 5 and is arranged close to it.

According to the developer supply hopper 120 configured as described above, the developer 2 that has passed through the developer supply port 124
Is immediately captured by the magnetic force generated by the magnet roller 6 included in the developing sleeve 5, so that the developer 2 maintains the developer distribution when passing through the slit-shaped agent supply port 124, It will be set on the sleeve surface without staying on the developing sleeve 5. According to this, it is possible to set the developer on the developing sleeve 5 more stably and more uniformly than in the configuration of the first embodiment. Further, since the developer can be prevented from spilling outside or scattering to the surroundings when the developer is supplied, it is possible to improve the agent supply amount control accuracy. Moreover, in the case where dust-proof means such as suction is provided to collect the developer not set on the developing sleeve 5, the dust-proof means can be simplified, so that the dust-proof means can be used on the production line. Maintenance is also easy.

FIG. 5 is a partial cross-sectional view showing another structural example of the third embodiment. In this example, the developer supplying hopper 12
2 is arranged directly above the developing sleeve 5, and the direction of the agent supply port 125 faces the developing sleeve 5 and is arranged close to it. A shutter portion 126 for allowing or limiting passage of the developer 2 from the supply port 125 is arranged near the agent supply port 125. Shutter section 1
26 is configured to operate in the direction of the arrow in the figure, and in the figure, the solid line indicates the open position and the broken line indicates the closed position. The operation of the shutter section 126 is controlled by a drive mechanism (not shown).

Also in the developer supplying hopper 122 having the above-described structure, as in the structure shown in FIG. 3, the developer 2 that has passed through the developer supplying port 125 is the magnet roller contained in the developing sleeve 5. Since the developer 2 is immediately captured by the magnetic force generated in 6, the developer 2 is retained on the developing sleeve 5 while retaining the developer distribution when passing through the slit-shaped agent supply port 124. It will be set on the sleeve surface.

[Fourth Embodiment] FIG. 6 is a partial cross-sectional view showing a schematic structure of a developing device and a developer supplying hopper according to a fourth embodiment. However, the configuration of the developing device 100 is the same as that in FIG. The developer supplying hopper 130 of the fourth embodiment
Is a hopper body 130a as a developer storing means for storing the developer 2, and a developer supply port 134 configured to be openable and closable.
And a developer supply roller 135 as guide means for guiding the developer 2 in the developer supply direction by rotation.

In the vicinity of the agent supply port 134, the supply port 13
A shutter portion 133 is provided to allow or limit the passage of the developer 2 from the roller 4. This shutter unit 133
Is configured to operate in the direction of the arrow in the figure,
In the figure, the solid line indicates the open position and the broken line indicates the closed position. The operation of the shutter section 133 is controlled by a drive mechanism (not shown). In addition, the agent supply port 134
Is formed in a slit shape along the longitudinal direction of the developing sleeve 5, as in the first embodiment.

The agent supplying roller 135 is the developing sleeve 5.
And a magnet 137 as a magnetic field generating means is fixedly arranged at a position shown in the drawing. Agent supply roller 13
Reference numeral 5 is rotationally driven at a constant speed in the arrow direction by a drive mechanism (not shown). Magnet 13 fixedly arranged in the roller
The magnetic force of No. 7 acts uniformly in the longitudinal direction of the agent supply roller 135 and in the same direction. Also, the magnet 13
The magnetic force of 7 acts on the vicinity of the agent supply port 134 through the surface of the roller, and the direction of the magnetic force of the developer 2 is the roller 13 for supplying the agent.
5 It is oriented in the direction of capturing on the surface. In FIG. 6, the magnetic poles (P1 to P4) of the magnet roller 6 and the magnetic force lines of the magnet 137 and their directions are shown. Here, the magnetic pole of the magnet 137 has an S pole on the surface side of the agent supply roller 135 and an N pole on the center side.

According to the developer supplying hopper 130 configured as described above, the developer 2 is captured on the roller surface by the magnetic force acting on the surface of the agent supplying roller 135.
Since the roller 135 is forcibly conveyed toward the agent supply port 114 as the roller 135 rotates, fluctuations in the developer supply amount are suppressed even when the developer has poor fluidity, and the amount per unit time is reduced. The agent supply amount can be made stable and uniform.
Particularly, since a powder pressure of a predetermined level or more is applied to the developer conveyed on the roller by the magnetic force toward the roller surface, the developer is more reliably captured on the roller surface. Therefore, as compared with the case where the developer is conveyed by the rotation of the roller as in the third embodiment, the fluctuation of the supply amount of the developer is more effectively suppressed, and the accuracy of the developer supply amount control is further improved. It is also possible to control the amount of supply of the agent easily.

Further, in the configuration of the fourth embodiment, since the magnetic force of the agent supply roller 135 mainly acts in the vicinity of the agent supply port 125, the developer after being discharged from the agent supply port 125 is developed. It will be captured by the magnetic force of the sleeve 5. Therefore, it is possible to suppress the fluctuation of the developer supply amount caused by the developer carried on the developing sleeve 5 being taken into the developer supplying roller 135 again or spilling from the developing sleeve 5.

In each of the above embodiments, since the magnet roller 6 fixedly arranged inside the developing sleeve 5 is composed of magnetic poles (P1 to P4), the magnetic force direction between the poles is toward the developing sleeve 5 side. However, by properly adjusting the magnetic force of the agent supply roller 135, the above-mentioned problem can be prevented.

[Fifth Embodiment] Next, as a fifth embodiment,
An embodiment will be described in which, when the developing device 100 is returned to the manufacturer for reasons such as the life of the developer, the developer is recovered using the developer supplying hopper. Figure 7
FIG. 13 is a partial cross-sectional view showing a schematic configuration of a developing device and a developer supply hopper according to a fifth embodiment. FIG. 7 shows an example in which the device configuration of the fourth embodiment shown in FIG. 6 is used for collecting the developer, and the same parts as those in FIG. 6 are denoted by the same reference numerals.

In the fifth embodiment, in order to collect the developer carried on the developing sleeve 5, the developing sleeve 5
An agent scraper 138 is disposed between the roller and the agent supply roller 135. Further, the direction of the S pole of the magnet 137 contained in the agent supply roller 135 is changed to the developing sleeve 5 side so that the magnetic force acts on the developing sleeve 5 side. Further, the shutter section 133 is opened.

In the above-described structure, when the developing sleeve 5 is rotationally driven in the direction of the arrow and the agent supply roller 135 is rotated in the opposite direction (the direction of the arrow in the drawing) to the direction during the supply, the developing sleeve 5 is rotated. The developer on the surface is scraped off by the agent scraper 138 as the sleeve rotates,
Collected on the agent supply roller 135 side. Then, the collected developer is captured on the surface of the roller by the magnetic force of the agent supply roller 135, and is stored in the hopper main body 130a as the roller rotates. Even if the S pole of the magnet 137 has the same orientation as in FIG. 6, it is possible to obtain substantially the same action.

According to the configuration of FIG. 7, the developer can be supplied and recovered by commonly using the main parts of the same developer supply hopper, so that the cost on the production line is included. It is possible to reduce the total cost and save space.

Incidentally, the developer can be collected by the constitution of other embodiments. For example, the developer can be stored in the hopper main body 110a by providing the agent scraper 138 in the configuration of FIG. 3 and rotating the agent supply roller 135 in the opposite direction to the direction at the time of supply. Also, FIG.
In the above configuration, the developer can be collected even if the direction of the magnetic force of the magnet 137 contained in the agent supply roller 135 remains as shown in FIG.

[0056]

According to the invention of claims 1 to 6, since the developer can be uniformly set in a required amount along the longitudinal direction of the developer carrying member, the developer can be set uniformly. It is no longer necessary to install the mechanism of
It is possible to achieve simplification of the structure of the developing device, cost reduction, and space saving. Further, when the developing device is mounted on the main body of the copying machine, it is possible to save the trouble of sending the developer to the developer carrier and making the developer balance uniform, so that the productivity and the maintainability of the developing device can be improved. User operability can be improved.

In particular, according to the second aspect of the invention, the developer supplied onto the developer carrying member can be set within the carrying width of the developer carrying member. It is possible to prevent the developer from overflowing at the end portions of.

In particular, according to the third aspect of the invention, the developer is forcibly conveyed toward the agent supply port along with the surface movement of the guide means, so that even if the fluidity of the developer is poor, Fluctuations in the supply amount can be suppressed, and the supply amount of the agent can be made stable and uniform.

In particular, according to the invention of claim 4, the developer is supplied to the developer carrier without remaining while maintaining the distribution of the developer when passing through the slit-shaped agent supply port. Thus, the setting of the developer on the developer carrier can be performed stably and uniformly.

In particular, according to the invention of claim 5, the developer is forcibly conveyed toward the agent supply port as the surface of the guide means moves while being caught by the magnetic force generated by the guide means. Even when the fluidity is poor, the fluctuation of the developer supply amount is suppressed, and the developer supply amount can be made stable and uniform.

In particular, according to the invention of claim 6, since the developer discharged from the developer supply port is captured by the magnetic force of the developer carrier, the developer carried on the developer carrier is guided again. Fluctuations in the supply amount of the developer due to being taken in by the toner or spilled from the developing carrier can be suppressed.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view illustrating a schematic configuration of a developer supply hopper of a developing device according to a first embodiment.

FIG. 2 is a plan view of an essential part of FIG.

FIG. 3 is a partial cross-sectional view showing a schematic configuration of a developing device and a developer supply hopper according to a second embodiment.

FIG. 4 is a partial cross-sectional view showing a schematic configuration of a developing device and a developer supply hopper according to a third embodiment.

FIG. 5 is a partial cross-sectional view showing another configuration example of the third embodiment.

FIG. 6 is a partial cross-sectional view showing a schematic configuration of a developing device and a developer supply hopper according to a fourth embodiment.

FIG. 7 is a partial cross-sectional view showing a schematic configuration of a developing device and a developer supply hopper according to a fifth embodiment.

[Explanation of symbols]

1 Developer supply hopper 2 developer 3 Shutter section 4 agent supply port 5 Development sleeve 6 magnet roller 7 Doctor 8 Hisashi 10 Support case 100 developing device

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Claims (6)

(57) [Claims] 1. A developer carrying member carrying on its surface a developer comprising toner and magnetic particles, a magnetic field generating means contained in the developer carrying member, and an amount of the developer carried on the developer carrying member. For controlling the developer, a developer retaining portion of a predetermined volume in which the developer regulated by the developer regulating member retains, and a developer retaining portion in the developer conveying direction on the developer carrier. A developer supply device that supplies the developer from outside the development device to the development device , which is adjacent to the upstream side and has a toner storage portion having a toner supply port facing the developer carrier , prior to shipment of the development device. The developer storage means includes a developer storage means for storing a developer, and a slit-shaped developer supply port along the longitudinal direction of the developer carrier, which is configured to be openable and closable. The developer stored in the A developer supply device characterized in that the developer is supplied onto the surface of an image carrier. 2. The developer supply device according to claim 1, wherein the width of the developer supply port in the longitudinal direction is a length that does not exceed the carrying width of the developer on the developer carrying member. Agent supply device. 3. The developer supply device according to claim 1, wherein the developer supply port is provided with guide means for guiding the developer in a developer supply direction by surface movement. 4. The developer supply device according to claim 1, wherein the developer supply port faces and approaches the developer carrier when supplying the developer to the surface of the developer carrier. A developer supply device characterized in that the developer supply device is arranged. 5. The developer supply device according to claim 3, wherein a magnetic field generating means is provided inside said guiding means, and the magnetic force of said magnetic field generating means is maintained while the developing means is guided by said guiding means. The developer supply device is characterized in that the developer is captured by. 6. The developer supply device according to claim 5, wherein after the developer is discharged from the developer supply port, the developer is captured by the magnetic force of the magnetic field generating means included in the developer carrier. A developer supply device characterized in that