JP2000098721A - Toner supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact toner supply device constituted so that the controlled quantity of toner can be directly supplied to a developing device from a toner housing container independently arranged of the developing device as a separated body. SOLUTION: This toner supply device is provided with the toner housing container 20 in which the toner supplied to the developing device 10 and which is independently arranged of the developing device 10 as the separated body and a screw pump 41 arranged at one part of the developing device 10 so as to suck the toner housed in the container 20. Then, the toner sucked by the pump 41 is supplied to one end part side of a stirring screw 12 through a supply hole 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner replenishing device for replenishing toner stored in a toner storing member to a developing device of an image forming apparatus.

[0002]

2. Description of the Related Art In an image forming apparatus of the above-mentioned type, toner density is detected and toner is replenished so as to keep the mixing ratio of toner and carrier in a developing device constant, thereby controlling the image density. . For this reason, a toner container such as a toner bottle or a cartridge is disposed in or near the unit having the developing device, and the amount of toner consumed by the use from the toner container directly or via the toner hopper is supplied into the developing device. It is configured to be. In this case, the transfer and replenishment of the toner from the toner storage unit to the developing device is performed by a mechanical auger such as a screw or a paddle.

However, when the toner is replenished by the mechanical auger means, the toner storage unit and the toner replenishing device have to be installed at a position integral with or very close to the developing device because the screw is arranged almost linearly. Did not get. For this reason, the configuration of the toner replenishing device becomes complicated, which hinders high cost, low productivity, and machine maintainability, and it is also difficult to secure and maintain the toner quality characteristics.
In addition, there is a difficulty in the operability of the user for replacing the toner container.

Further, since the conventional toner container is made of a hard bottle such as a cartridge or a bottle, there is a great problem in disposing of the used container accompanying the replacement of the toner container. That is, the used toner storage container is collected by the manufacturer from the user, and is recycled, reused, and incinerated. However, the container is bulky and requires a high distribution cost until it is collected.

Further, when the collected toner storage container is to be reused, it is difficult to clean the container, the toner filling efficiency is also difficult, and the cost required for reusing the toner storage container is high. Was.

Incidentally, there has been conventionally proposed a toner container capable of reducing the volume of the toner container.

[0007]

However, a toner storage container whose volume can be reduced cannot maintain a stable replenishing performance when replenishing the container by using a toner replenishing device, and when the toner is transported. Even when using a container whose volume can be reduced only, there is a problem that toner is contaminated when transferring the toner, and the container has not been put to practical use.

The present invention solves the above-mentioned conventional problems,
It is an object of the present invention to provide a compact toner replenishing device that can supply a controlled amount of toner to a developing device directly from a toner storage container provided separately and independently of the developing device.

[0009]

In order to achieve the above-mentioned object, the present invention provides a developer carrying member arranged opposite to an image carrying member, and a toner having an axis parallel to the axis of the developer carrying member. In a toner replenishing device for replenishing toner to a developing device having a transporting member for transporting a developer, a toner storing member for storing toner to be replenished to the developing device and provided separately and separately from the developing device And a suction unit provided in a part of the developing device for sucking the toner stored in the toner storage member, wherein the toner sucked by the suction unit receives one end of the transport member through a supply hole. It is characterized by being supplied to the department side.

The present invention is effective when the suction means is drivingly connected to the transport means via an intermittent means for intermittently driving. Furthermore, the present invention is effective when the suction unit is driven via a driving unit independent of the conveyance unit and the driving unit.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a configuration diagram of the agent supply device according to the present invention.

In FIG. 1, the agent replenishing device of the present embodiment replenishes toner to a developing device 10, and includes a toner container 20 serving as a storing device for storing toner, and a toner stored in the toner storing device. And a powder pump means 40 as a suction means for transferring the toner to the developing device 10.

As shown in FIGS. 1 to 4, the developing device 10 has a developing sleeve 11 as a developer carrier opposed to the photoreceptor 1 as an image carrier, and an axis line with the developing sleeve 11. A first stirring screw 12 and a second stirring screw 13 are provided as parallel conveying members. The developer in the developing device 10 is circulated so as to be conveyed from left to right in FIG. 2 by the first stirring screw 12 and from right to left by the second stirring screw 13. During this circulation, the electrostatic latent image formed on the photoconductor 1 is developed with the toner of the developer transferred to the developing sleeve 11 in the middle of the transport path.

As shown in FIG. 2, the developing device 10 is provided with a powder pump means 40 at the front end of the apparatus. The powder pump means 40 includes a suction-type uniaxial eccentric screw pump 41. The configuration of the screw pump 41 is such that the rotor 42 is formed in an eccentric screw shape with a rigid material such as a metal, and the screw is formed in a two-screw shape formed of an elastic body such as rubber, and is fixedly installed. And a holder 44 made of a resin material or the like that wraps the stator 43 and forms a powder conveyance path. In the present embodiment, the gear 16 integrally connected to the first stirring screw 12 and the drive shaft 43 of the rotor 42
The gear 45 is meshed with a gear 45 integrally connected thereto, and the gear 45 is provided with an electromagnetic clutch 46 as an intermittent means for intermittently rotating and driving the gear 16.

The single-axis eccentric screw pump 41
When the agitating screw 12 and the agitating screw 12 are connected and driven, the agitating screws 12 and 13 are driven to rotate almost constantly, so that the toner is replenished as needed, and the toner is replenished based on the concentration control of the developer. It cannot be applied to the device.

Therefore, by controlling the driving of the screw pump 41 by the electromagnetic clutch 46, the present invention can be applied to a developing device of a type in which the developer concentration in the developing device 10 is controlled to be constant. That is, the developing device 10
A known developer concentration detection and control method can be adopted. In this case, the magnetic permeability detector 18 is provided in the developing device 10, and the detector 18 detects a change in the mixing ratio of the toner and the carrier in the developing device 10. And
When the magnetic permeability detector 18 detects that the amount of toner is small, the electromagnetic clutch 46 is turned on, and the single-axis eccentric screw pump 41 is operated to supply toner. When the concentration of the developer in the developing device 10 reaches a predetermined concentration, the screw pump 41 does not operate even when the electromagnetic clutch 46 is turned off and the stirring screw 12 is rotated, and the toner is not supplied. The developing device 10 may adopt a method of detecting the reflection density of the toner image formed on the photoconductor and controlling the toner supply amount.

The screw pump 41 includes a rotor 42
A strong self-suction force is generated by the rotation of, and toner can be sucked from the toner storage container 20. The sucked-in toner is transferred into the developing device 10 by the supply hole 17 formed between the screw pump 41 and the first stirring screw 12, and during the transfer process when the two-component developing system is used. The toner replenished with the developer is mixed with the developer in the developing device 10 with stirring, so that a uniform developer concentration and an appropriate charge amount are obtained. The developing device includes a deaeration hole 14a and the deaeration hole 14a.
a is provided, and air transported together with the toner is degassed from the developing device 10.
It is configured to prevent the toner from scattering. The tube 15 connected to the suction part of the single-axis eccentric screw pump 41 is a flexible tube having a diameter of, for example, 4 to 10 mm, and is made of a rubber material having excellent toner resistance (for example, polyurethane, nitrile, EPDM, silicon, or the like). It is very effective to use one that is

FIG. 5 is a partial sectional view showing an embodiment of the agent container according to the present invention. In FIG. 5, a toner container 20 is a bag body 2 as a container body formed in a bag shape.
1, and a toner discharge unit 22 and an air supply unit 30 are provided on the top of the unit 1. A toner guide base member 23 is connected to the toner discharge section 22 of the toner storage container 21, and an air supply base member 31 is welded to the air supply section 30 by ultrasonic waves or the like.
Further, the bag body 21 is made of a resin such as polyethylene or nylon, and is made of a flexible sheet having a thickness of about 80 to 120 μm in a single-layer or multilayer structure.
The periphery of the bag body 21 is also welded by ultrasonic waves or the like to form a sealed structure. In addition, it is effective to deal with static electricity by subjecting the surface of the sheet constituting the bag body 21 to aluminum vapor deposition. Further, the toner guide base member 23 and the air supply base member 31 can also be made of a resin such as polyethylene or nylon. If the same material as the bag body 21 is used, it is convenient for recycling. A partition member 24 is provided between the toner discharge unit 22 and the air supply unit 30 at the upper part of the bag body 21. The partition member 24 extends downward from the upper part and reaches near the lower part of the bag body 21. To form two chambers. The lower end of the partition member 24 and the bag 2
An open part up to the bottom of 1 connects the two chambers.
6.

The toner guide cap member 23 is provided with a toner discharge port 25 formed in a pipe shape, and a lid member 50 is attached to an upper portion of the toner discharge port 25.
The toner outlet is closed. Further, a screw portion 27 is formed in the toner guide base member 23, and the screw portion 2 is formed.
A cap 28 is screwed into 7. This cap 2
Reference numeral 8 denotes a seal for sealing the toner discharge port 25, which is attached at the time of shipment from a factory to prevent toner scattering and deterioration. The cap 28 is attached so as to completely cover the lid member 50. Thus, even if the user removes the cap 28 and accidentally falls down the bag 21, the cap member 50 can be used. There is no danger of toner scattering. The toner guide cap member 23
Is provided with an air discharge port 29 near the toner discharge port 25, and the air discharge port 29 is covered with a filter 39 that allows air to pass but does not allow toner to pass.

As shown in FIG. 6, the lid member 50 is formed in a cap shape with a slight step in the middle.
A protrusion 51 is formed on the head, and a toner suction port 68 described later is formed on the peripheral surface of the slightly larger diameter portion.
An opening 52 having substantially the same diameter as the opening 52 is formed.

An air inlet 32 is formed in the air supply base member 31, and the air inlet 32 is provided by a valve 33 provided at a lower portion of the air supply base member 31, that is, inside the bag body 21. It is closed. This valve 33
The air supply base member 31 is integrally attached to the base member 31 and has a spring property that is constantly urged in a direction to close the air inlet 32. Therefore, the air inlet 32 is normally closed by the valve 33, and there is no possibility that toner scatters from the air inlet 32.

Next, a description will be given of the operation of the toner container 20 constructed as described above when toner is supplied. As described above, when the toner supply is started, the toner outlet 25 is closed by the lid member 50 even if the cap 28 is removed. Therefore, in the present embodiment, an external operation member 60 for moving the lid member 50 by an external operation to connect the toner discharge port 25 to the toner suction port 68 is provided.
The external operation member 60 is screwed and attached to the screw portion 27 from which the cap 28 has been removed.

The external operation member 60 includes a holder 61 attached to the toner guide base member 23, and the holder 61.
It has a slider 62 and a chuck 64 slidably fitted therein, a compression spring 63 for urging the slider 62 downward elastic force, and a grip portion 65 provided integrally with the chuck 64. And the holder 61
Is provided with a toner suction port 68 on the side of.

As shown in FIG. 7, the toner container 20 initially has the lid member 50 closing the toner discharge port 25,
Here, when the handle 65 is pulled upward, the chuck 64 fixed integrally with the handle 65 and the chuck 64 are further fixed.
The slider 62 engaged with the slider also moves. at the same time,
When the slider 62 is pressed downward by the compression spring 63, the chuck 64 is closed, the projection 51 of the lid member 50 is grasped, and the lid member 50 is lifted. further. Handle 6
5 is pulled up and twisted 90 degrees, a locking pin 66 integrally provided with the handle 65 is locked to the upper end portion 67 of the holder 61, whereby the position shown in FIG. Is held. When the lid member 50 is lifted, the opening 52 provided in a part of the side wall coincides with the toner suction port 68, and the toner suction port 6
8 communicates with the toner outlet 25.

As described above, the cover member 50 is operated by an external operation.
Can be moved to the open position, so that toner can be prevented from being scattered at the time of toner replenishment and replacement of the toner storage container 20. Reference numeral 53 is a seal member such as an O-ring.

A connector 70 is attached to the air inlet 32 of the air supply base member 31. This connector 70
Is provided with a hollow air introduction passage 71 therein, a sealing member 72 such as an O-ring at the outer peripheral portion of the end portion, and a nozzle portion 73 inserted into the air inlet 32. A tube 34 is provided at the opposite end of the nozzle portion 73. Are connected, and air is introduced from an air pump (not shown) through the tube 34. When the nozzle portion 73 of the connector 70 is inserted into the air inlet 32, the nozzle portion 73 pushes down the valve 33 to open the valve.

The toner container 20 constructed as described above
A replenishing device that uses a sensor detects a change in the mixing ratio of toner and carrier based on a conventionally known magnetic permeability detector (not shown) provided in a part of the developing device 10, and the detected value is determined to be a certain value. When the value is equal to or less than the value, toner supply is started. At the time of toner supply, the toner storage container 20 is first supplied with air via a tube 34 from a processing pump (not shown). The air is ejected from the nozzle portion 73 into the toner container 20 through the air introduction path 71. The screw pump 41 of the toner transfer means 40 is turned on at the same time as the air pump or with a slight time lag, whereby the toner in the toner storage container 20 is transferred to the developing device 10. That is, the toner in the toner container 20 reaches the screw pump 41 via the toner outlet 25, the opening 52 of the lid member 50, the toner inlet 68 and the tube 15, and is supplied to the developing device 10. The air ejected into the toner container 20 is transferred to the screw pump 41 together with the toner, and the excess air is discharged from the air discharge port 29 through the filter 39 to the outside.

By ejecting air from the air supply base member 31 as described above, the toner layer in the toner container 20 is diffused, and the fluidization of the toner is promoted.
Therefore, electrophotographic toner with very poor fluidity,
By being fluidized by air, the occurrence of a crosslinking phenomenon is prevented, and the movement of the toner becomes more reliable. Further, since toner aggregation does not occur, the physical properties of the toner are always stable, and high-quality development quality can be obtained.

Further, in the present embodiment, the partition member 24 is provided on the bag 21, and the space of the meat portion of the bag 21 is divided into the air discharge side and the air discharge side, so that it is clearly shown in FIG. In addition, the air and the toner can be smoothly moved in the direction of the arrow by the discharge pressure of the air and the suction pressure of the screw pump 41.

Further, since the bag body 21 is flexible, the volume of the bag body 21 is reduced as the suction of the toner progresses. The toner in the bag body 21 is transported closer to the toner outlet 25 because the air outlet 29 is provided in the vicinity of the toner outlet 25. The suction efficiency of the pump 41 is increased, and the stored toner can be discharged without remaining in the bag. Furthermore, since the toner in the bag 21 is not subjected to mechanical stress and is fluidized by air, the toner physical properties can be stabilized and maintained without occurrence of toner blocking or the like.

As described above, the bag-shaped toner storage member 20
The stable toner transfer can be achieved regardless of the amount of stored toner. Further, restrictions on the mounting direction of the bag-shaped toner storage member 20 (vertical placement, stacking, oblique placement, etc.) are reduced, and the toner supply operation of the user can be performed without restricting the location of the toner supply device in the image forming apparatus. The effects such as being simple can be achieved.

Further, the toner discharge port 25 has a role of a suction port for sucking the toner stored in the bag body 21, but can also function as a filling port for filling the toner in a factory. Similarly, filling of the toner from the air supply base member 31 is also possible. Further, in order to increase the toner filling efficiency, it is possible to use one of the ports for venting air at the time of filling the toner.

Further, when the toner container 20 collected from the user is to be reused, it is necessary to clean the inside of the toner container 20 before the toner refilling step. Cleaning can be easily performed by supplying cleaning air from one of the outlet 25 and the air inlet 32 of the air supply base member 31 and removing the air from the other port. Therefore, there is an advantage that the toner storage container 20 can be reused at low cost.

When the external operation member is removed from the toner container 20, the above operation steps are performed in reverse. That is, when the handle 65 is twisted by 90 degrees, the compression spring 63
The slider 61, the handle 65, and the chuck 64 move, and return to the state of FIG.

In the above-described toner replenishment control, it is also possible to detect the density of a toner image formed on a conventionally known photosensitive drum in place of the magnetic permeability detector. FIG. 9 shows a modification of FIG. 8. In this example, the external operation member 60 is not used, and the toner guide base member 2 is not used.
A toner discharge connector 80 is attached to the holder 3 instead of the holder 61. The connector 80 has substantially the same configuration as the connector 70. The connector 80 includes a hollow toner passage 81 inside, a seal member 82 such as an O-ring at the outer peripheral portion of the end portion, and a nozzle portion 83 inserted into the toner discharge port 25. I have it. Further, the toner guide base member 23 is provided with a valve 84 for closing the toner discharge port 25 inside the bag body 21.

The tube 1 is connected to the toner discharging connector 80.
5 is connected, the valve 84 is opened by inserting the nozzle portion 83 into the toner discharge port 25, and toner can be supplied.

According to this method, there is an advantage that the configuration is simple and the cost can be reduced.
FIG. 10 shows a modified example of the toner container, in which the toner container 20 of the present example is formed in an elongated rectangular shape, a toner discharge portion 22 is provided at one end in the longitudinal direction, and air supply is provided at the other end. A unit 30 is provided. The toner discharge unit 22 and the air supply unit 30 use a base member, a connector, and the like configured in the same manner as in the example of FIG. 9, and the same members are denoted by the same reference numerals.

This method is very effective in a case where the installation place of the toner container 20 is very narrow and it has to be installed in an elongated place. According to the present invention, since the toner storage container 20 is provided with the repeatedly usable valves 33 and 83 and the lid member 50 for sealing the container, not only when the toner storage container 20 is replaced, Even if the toner container 20 is detached and attached before the toner is used, no toner scattering occurs. Further, the toner storage container 20 in use can be used again as it is. Further, the used toner storage container 20 has a very small hard base, so that the container can be arbitrarily rounded or folded, which is extremely efficient in terms of collection and transportation, and can be realized at low distribution cost. .

The driving and control of the toner replenishing device are as follows.
A drive motor and an air pump are driven and controlled by a power outlet (not shown), a power supply, a switch (not shown), and a control circuit. These may use a conventionally well-known technique.

By the way, it is known that the toner used in an electrophotographic image forming apparatus has extremely poor fluidity and is difficult to transfer. Originally, when transferring the toner, it is not desirable to apply a large mechanical stress to the toner. When an abnormal stress is applied to the toner, blocking (aggregation due to thermal fusion), crushing, etc. of the toner may occur, causing not only deterioration of the toner characteristics and inability to transfer, but also transfer members (coils, screws, pipes, etc.), driving This causes damage to the members. Therefore, when transferring the toner, it is important to devise as little abnormal mechanical stress as possible to the toner.

In the conventional toner replenishing apparatus, since the transfer is performed by the auger and the pipe as described above, if the mechanical stress due to the auger and the mechanical stress due to the friction generated between the auger and the pipe are very large. I had no choice. In this case, the longer the transfer distance and the more the transfer direction is displaced, the worse. In addition, the torque required for driving the auger becomes very large, so that the cost of the driving member and the power consumption cannot be ignored.

For these reasons, when it is desired to increase the transfer distance or to change the transfer direction, it is necessary to perform multistage transfer using a plurality of augers and pipes. This has resulted in further deterioration of toner characteristics, an increase in the number of parts, an increase in cost, a decrease in reliability, a reduction in maintenance and productivity of the apparatus, an increase in the installation volume of the toner supply apparatus, and a decrease in operability. .

The present toner replenishing device only needs to connect a flexible toner transfer pipe to the developing device 10 of the image forming apparatus, and there is no scattering of toner. Also, since there is no restriction on the installation position and location of the toner supply device with respect to the developing device,
The toner storage section can be provided in a place where the operability at the time of replacement of the toner storage (supply) container by the user is most easily performed.

FIG. 11 is an explanatory view showing still another embodiment of the present invention. In this embodiment, the screw pump 41 is driven by a dedicated motor 47. That is, the developing device 10 is driven by a driving source different from the stirring screws 12 and 13. Even in this case, the amount of toner based on the developer density control can be supplied to the developing device 10.

[0045]

According to the structure of the first aspect, the agent can be reliably transferred from the container storing the toner and the developer without being scattered, and the exchange of the toner and the developer is easy without being restricted by the shape of the container. Can be done.

According to the second and third aspects, it is possible to replenish the developing device with a toner amount according to the toner density control.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram for explaining a configuration of the present invention.

FIG. 2 is an explanatory sectional view showing a toner receiving portion of the developing device.

FIG. 3 is an explanatory plan view showing a toner receiving portion of the developing device.

FIG. 4 is an explanatory side view showing a toner receiving portion of the developing device.

FIG. 5 is a sectional view of the toner container according to the present invention.

FIG. 6 is a perspective view of a cap and a lid member.

FIG. 7A is an enlarged sectional view showing a state where a lid member of the toner container according to the present invention is closed, and FIG. 7B is a plan view thereof.

FIG. 8A is an enlarged sectional view showing a state where a lid member of the toner container according to the present invention is opened, and FIG. 8B is a plan view thereof.

FIG. 9 is an explanatory sectional view showing a modification of the present invention.

FIG. 10 is an explanatory sectional view showing another modification of the present invention.

FIG. 11 is an explanatory cross-sectional view of a developing device showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Photoconductor drum 10 Developing device 11 Developing sleeve 12, 13 Stirring screw 20 Toner storage container 21 Bag 22 Toner discharge part 25 Toner discharge port 30 Air supply part 33, 83 Valve 40 Toner transfer means 46 Electromagnetic clutch 47 Drive motor

Claims (3)

[Claims] 1. A developing device comprising: a developer carrier opposed to an image carrier; and a toner having an axis parallel to an axis of the developer carrier or a transport member for transporting the developer. A toner storage member that stores toner to be supplied to the developing device, is provided separately and separately from the developing device, and the developing device sucks the toner stored in the toner storage member. And a suction unit provided in a part of the apparatus, wherein the toner sucked by the suction unit is supplied to one end side of the conveying member through a supply hole. 2. The toner replenishing apparatus according to claim 1, wherein said suction means is drivingly connected via intermittent means for intermittently driving said developing device. 3. The toner replenishing apparatus according to claim 1, wherein the suction unit is driven via a driving unit independent of the driving of the developing device.