JP2004184589A - Toner carrying device and image forming apparatus provided with toner carrying device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner carrying device by which toner can be stably carried for a long distance over a long period of time and an image forming apparatus using the toner carrying device. <P>SOLUTION: In the toner carrying device carrying the toner, at least a toner mixing part, a toner separating part, a 1st carrying means and a 2nd carrying means are provided. A sealed circulating path for air, reaching the toner separating part from the toner mixing part by going through the 1st carrying means, and then, returning to the toner mixing part again through the 2nd carrying means is formed. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a toner conveying device and an electrophotographic image forming apparatus having the toner conveying device.
[0002]
[Prior art]
In a high-speed image forming apparatus or a color image forming apparatus, there is a problem that it is difficult to arrange the toner storing section near the developing device because the volume of the toner storing section for storing the toner is large. .
[0003]
As means for solving such a problem, a toner replenishment technique has been developed in which toner is transported from a toner storage section to a developing device by a toner transport method called air transport that can transport toner to a distance.
[0004]
The basic configuration of a toner replenishing device using air conveyance includes a toner mixing unit that mixes toner and air, a conveying unit that conveys a toner fluid in which air is mixed with toner in the toner mixing unit, and a conveying unit that conveys the toner fluid. This is a toner separation unit that separates toner.
[0005]
Further, the toner separating unit is provided with a filter for discharging air to the outside so as not to scatter the toner to the outside (for example, see Patent Documents 1 and 2).
[0006]
[Patent Document 1]
JP 10-97130 A
[Patent Document 2]
JP-A-10-268641
[Problems to be solved by the invention]
However, in the conventional toner conveying technology, when a mixed fluid of toner and air is conveyed from the toner storing section to the developing device by a fluid conveying means such as a pump, air is introduced from the outside in the toner mixing section, and further, in the toner separating section. After separating into toner and air, the air is discharged to the outside through a filter. Therefore, it is difficult to increase the toner transport distance because extra energy is applied to the pump to take air into the apparatus and discharge air outside the apparatus. Further, the filter is clogged by toner or the like, so that there is a problem that stable toner conveyance cannot be performed.
[0009]
SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a toner transport device capable of stably transporting toner over a long distance for a long period of time, and an image forming method using the toner transport device. It is to provide a device.
[0010]
[Means for Solving the Problems]
The object of the present invention is achieved by the following configurations.
[0011]
(1) A toner conveying device that conveys toner, including at least a toner mixing unit, a toner separating unit, a first conveying unit, and a second conveying unit, wherein the toner mixing unit introduces toner. A first toner transporting unit that mixes air into the toner introduced from the toner introducing unit to form a toner fluid, wherein the first transporting unit separates the toner fluid in the toner mixing unit from the toner mixing unit; And a toner discharge unit that separates the toner fluid transported by the first transport unit into air and toner, and further discharges the toner to the outside. The means conveys the air separated by the toner separating section from the toner separating section to the toner mixing section, reaches the toner separating section from the toner mixing section via the first conveying section, and controls the second conveying section. Through A toner conveying device, wherein a closed circulation passage for air returning to the toner mixing section is formed again.
[0012]
(2) The method according to (1), further comprising a control unit that detects a transport amount of the toner fluid of the first transport unit and controls an air transport amount of the second transport unit based on the transport amount. The toner conveying device according to claim 1.
[0013]
(3) The control means detects a transport amount of the toner fluid of the first transport means, and performs control for keeping a ratio between the transport amount and an air transport amount of the second transport means constant. (2) The toner conveying device according to (2).
[0014]
(4) The control unit detects a transport amount of the toner fluid of the first transport unit, and when the transport amount is equal to or less than a target transport amount, performs a control to increase an air transport amount of the second transport unit. (2) The toner conveying device according to (2).
[0015]
(5) The control unit detects a transport amount of the toner fluid of the first transport unit, and stops the first transport unit and the second transport unit when the transport amount is equal to or less than the target transport amount. The toner conveying device according to (2), which performs control.
[0016]
(6) There is a warning unit for giving a warning, wherein the control unit detects the transport amount of the toner fluid of the first transport unit, and when the transport amount is equal to or less than the target transport amount, issues a warning by the warning unit. The toner conveying device according to (2), wherein the toner conveying device performs control to be performed.
[0017]
(7) The controller according to any one of (2) to (6), wherein the control unit controls the toner introduction amount of the toner introduction unit based on the toner fluid conveyance amount of the first conveyance unit. Item 10. The toner conveying device according to item 8.
[0018]
(8) An image forming apparatus comprising the toner conveying device according to any one of (1) to (7).
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows an example of an image forming apparatus having the toner conveying device of the present invention.
[0020]
In FIG. 1, the automatic document feeder 20 conveys the documents placed on the document feed tray one by one to a reading position and stacks the read documents on a document discharge tray.
[0021]
The document reading unit 21 reads a document image and generates digital image data.
The image forming unit 22 forms an image on recording paper by an electrophotographic method.
[0022]
In the image forming unit 22, a charging device 2, an exposure device 3, a developing device 4, a transfer device 5, a separation device 6, and a cleaning device 7 are arranged around the drum-shaped photoconductor 1. Below the image forming unit 22, a paper feed unit 23 having a plurality of recording paper storage units is provided, and feeds recording paper to the image forming unit 22. Reference numeral 10 denotes a manual paper feed unit. The recording paper fed from the paper feeding unit 23 or the manual paper feeding unit 10 is supplied between the photoconductor 1 and the transfer device 5 by the registration roller 11, fixed by the fixing device 8, and discharged to the paper output tray 12. Is done.
[0023]
In response to the clockwise rotation of the photoconductor 1, a toner image is formed on the photoconductor 1 by charging by the charging device 2, image exposure by the exposure device 3, and development by the developing device 4. The formed toner image is transferred to recording paper by the transfer device 5. The recording paper to which the toner image has been transferred is discharged to a discharge tray 12 after being subjected to a fixing process in the fixing device 8.
[0024]
The developing device 4 develops the electrostatic latent image on the photoconductor 1 with a two-component developer containing a toner and a carrier or a one-component developer containing no toner or a toner and an additive without a carrier. The toner consumed by the development in the developing device 4 is transported from the toner container 31 and the toner hopper 30 by the toner transport device 24 of the present invention and replenished, and the toner concentration of the developer in the developing device 4 is always maintained at a predetermined value. You.
[0025]
1 will be described in more detail with reference to FIG.
FIG. 2 is a diagram illustrating an example of the toner conveying device of the present invention.
[0026]
The toner conveying device shown in FIG. 2 includes a toner mixing chamber 35 which is a toner mixing section according to the present invention, a pump 501 which is a first conveying means according to the present invention, transport pipes 40 and 41, and a second conveying means according to the present invention. Pump 502, transport pipes 42 and 43, the toner separation chamber 60 as the toner separation unit according to the present invention, and the control unit 70 as control means according to the present invention. The toner mixing chamber 35 has a toner introduction port 34 according to the toner introduction section of the present invention, and the toner separation section has a toner discharge port 68 according to the toner discharge section of the present invention.
[0027]
As shown in FIG. 2, the toner mixing chamber 35, the pumps 501 and 502, and the toner separation chamber 60 are connected by transport pipes 40, 41, 42, and 43.
[0028]
The toner is introduced from a toner hopper 30 having a stirring member 32 and a toner sensor 33 using a piezo element into a toner mixing chamber 35 through a toner introduction port 34, mixed with air to form a toner fluid, and is pumped by an arrow X1 by a pump 501. As shown, the toner fluid is conveyed from the toner mixing chamber 35 to the pump 501 and from the pump 501 to the toner separation chamber 60 as shown by the arrow X2, and the toner is supplied to the toner separation chamber 60. As shown, air separated from the toner fluid flows from the toner separation chamber 60 to the pump 502 and from the pump 502 to the toner mixing chamber 35 as shown by an arrow X4. Then, the toner separated in the toner separation chamber 60 is supplied to the developing device 4 from the toner outlet 68.
[0029]
The toner conveying device has a sealed structure in which toner and air cannot pass except for the toner inlet 34 and the toner outlet 68. As will be described later, the toner introduction port 34 and the toner discharge port 68 also have a structure that can introduce and discharge the toner without changing the pressure of the air flow path of the apparatus.
[0030]
In the present invention, the closed-circular flow path of air refers to a flow path that does not have a path leading to the outside such that the pressure state inside the flow path of air fluctuates. The passage leading to the outside such that the internal pressure state fluctuates corresponds to, for example, a filter portion provided in an air flow passage referred to in the related art.
[0031]
The toner conveying device of the present invention can efficiently use the energy of the first conveying unit for conveying the toner fluid by using the closed air passage as the air passage when circulating the air. Can be improved.
[0032]
The control unit 70 controls the number of rotations of each motor of the toner inlet 34, the toner outlet 68, and the pumps 501 and 502, and detects the amount of toner fluid carried by the pump 501.
[0033]
The toner mixing chamber 35 of the toner conveying device of the present invention will be further described with reference to FIG. A cylindrical toner container 31 and a toner hopper 30 are mounted in the toner mixing chamber 35, and the toner container 31 is rotated by a motor 38, so that the toner falls from the toner container 31 into the toner hopper 30 through the opening 30 a.
[0034]
The toner hopper 30 is provided with a rod-shaped stirring member 32 having a plurality of U-shaped portions. The rotation of the motor 39 a causes the stirring member 32 to rotate and fall from the toner hopper 30 to the toner introduction port 34 of the toner mixing chamber 35. The toner introduction port 34 has a rotary door-like structure, and can supply a predetermined amount of toner into the mixing chamber 35 without changing the pressure in the air flow path of the apparatus.
[0035]
As for the toner on the toner introduction port 34, the rotation of the motor 39 b causes the rotation of the toner introduction port 34 to introduce the toner into the toner mixing chamber 35. The supply amount of the toner can be controlled by the number of rotations of the motor 39b that drives the toner inlet 34.
[0036]
Since air is fed from the pump 502 into the toner mixing chamber 35 via the transport pipe 43, a toner fluid in which toner and air are mixed is formed.
[0037]
The pumps 501 and 502 of the toner conveying device of the present invention will be further described with reference to FIG.
[0038]
As the pumps 501 and 502, pumps 501 and 502 composed of a diaphragm pump are used as shown in FIG. 4, but a pump such as a screw pump disclosed in JP-A-7-219329 and JP-A-8-6368 is used. Any known pump, fan, or the like can be used. The pump 501 constitutes a first transport unit according to the present invention for transporting the toner fluid obtained by mixing the toner and the air together with the transport pipes 40 and 41 from the toner mixing chamber 35 to the toner separation chamber 60, and the pump 502 comprises the transport pipes 42 and 43. In addition, a second conveying unit according to the present invention for conveying air separated from the toner fluid in the toner separating chamber 60 from the toner separating chamber 60 to the toner mixing chamber 35 is constituted. In the illustrated example, pumps 501 and 502 having the same structure are used, but different pumps may be used.
[0039]
The pump 501 has an intake port connected to the transport pipe 40 and an exhaust port connected to the transport pipe 41. An intake port of the pump 502 is connected to the transport pipe 42, and an exhaust port is connected to the transport pipe 43. The pump chamber formed by the outer wall 50 is partitioned by an inner wall 51 into an intake chamber 50a and an exhaust chamber 50b. ) Is provided with a valve 54.
[0040]
Part of the outer shape of the pumps 501 and 502 is formed by a diaphragm 52 formed of an elastic body made of rubber, and the diaphragm 52 is driven by an eccentric rotating member 56 driven by a motor 55a (55b) to be in a state shown by a solid line. Deforms to the state shown by the dotted line.
[0041]
The eccentric rotary member 56 is rotated by the motor 55a (55b), and the rotation causes the diaphragm 52 to be deformed between a state shown by a solid line and a state shown by a dotted line, thereby changing the volume of the intake chamber 50a and increasing or decreasing the pressure in the intake chamber 50a. Let it. Due to the increase or decrease of the pressure, the valves 53 and 54 are deformed into the state shown by the solid line and the state shown by the dotted line, respectively, and transport the fluid in one direction as shown by the arrow.
[0042]
In the present invention, the effect of the present invention can be obtained by using only the transport pipes 40 and 41 without providing a power source such as the pump 502 for the second transport unit. However, in order to transport the toner for a longer distance, As will be described later, it is preferable that the second conveyance unit also conveys the toner using a power source such as a pump.
[0043]
With reference to FIG. 5, the toner separating chamber 60 of the toner conveying device of the present invention will be further described. The toner separating chamber 60 has an outer wall 61 forming the outer diameter of the toner separating chamber 60, inner walls 64 and 65 separating the inside of the toner separating section 60 into an introduction chamber 60A, an exhaust chamber, and an auxiliary inner wall 66. The exhaust chamber includes an exhaust part 60B.
[0044]
An air inlet 62 is provided in the introduction chamber 60A, and an air outlet 63 is provided in the exhaust part 60B. The auxiliary inner wall 66 guides the fall of the toner and suppresses the rise of the toner. A stirring member 67 having wings and a toner discharge port 68 are provided below the toner separation chamber 60. The toner discharge port 68 is for discharging the separated toner to the outside of the toner separation chamber 60, and is usually supplied to the developing device 4 in the image forming apparatus. The toner outlet 68 has a rotating door-like structure like the toner inlet 34, and supplies a predetermined toner from the toner separating unit 60 to the developing device 4 without changing the pressure in the air flow path of the device. be able to.
[0045]
The toner accumulated on the toner discharge port 68 is rotated by the rotation of a motor (not shown) so that the toner discharge port 68 rotates and the toner is discharged out of the toner separation chamber 60. The toner discharge amount can be controlled by the rotation speed of a motor (not shown) that drives the toner discharge port 68.
[0046]
The toner fluid in which the toner and the air are mixed is introduced into the introduction chamber 60A from the air introduction port 62 as shown by an arrow W1, and the toner falls as shown by W2. Although the introduction chamber 60A is filled with the toner fluid, it is partially raised as shown by an arrow W3 and conveyed to the exhaust part 60B under the pressure of the fluid conveyance force by the pump 502. Due to the specific gravity of the toner and the action of the auxiliary inner wall 66, the toner concentration in the mixed fluid that rises in the direction shown by the arrow W3 decreases, and the mixed fluid becomes a toner fluid consisting essentially of air. The toner fluid sent into the exhaust part 60B is further separated into toner and air, and the separated toner falls from the toner passage 63 as indicated by an arrow W4, and the separated air is transported as indicated by an arrow W5. Reflux by 42.
[0047]
As shown in the drawing, the vertical portion 65A of the inner wall 65 and the vertical portion 64A of the inner wall 64 form a communication passage for meandering the toner fluid. Due to such a meandering communication path, the toner content in the circulating air has a low value. The vertical portions 65A and 64A are cylindrical, and have a configuration in which the cylinder of the vertical portion 64A is disposed within the cylinder of the vertical portion 65A.
[0048]
2 to 5 operate as follows under the control of the control unit 70.
[0049]
The amount of toner in the toner hopper 30 is detected by a toner sensor 33 using a piezo element, and when the toner level falls below the level detected by the toner sensor 33, a motor 38 operates to transfer the toner from the toner container 31 to the toner hopper 30. Replenish.
[0050]
In order to transport the toner to the developing device 4, the motor 39a shown in FIG. 3 is operated to drive the stirring member 32 to stir the toner in the toner hopper 30, and to drive the motor 39b of the toner introduction port 34 to drive the toner. Is introduced into the toner mixing chamber 35.
[0051]
Furthermore, the motors 55a and 55b rotate and the pumps 501 and 502 operate according to the supply signal. By the operation of the pumps 501 and 502, an airflow is generated in the mixing chamber 35 to mix the toner and the air, and the toner fluid is transported to the toner separation chamber 60 via the transport pipes 40 and 41 by the transport force of the pump 501.
[0052]
The toner separated in the toner separation chamber 60 is supplied to the developing device 4 from the toner outlet 68. The separated air flows back to the mixing chamber 35 via the transport pipes 42 and 43 by the transport force of the pump 502.
[0053]
Further, the motor of the toner outlet 68 rotates, and the toner is supplied to the developing device 4.
[0054]
The control of each motor based on the supply signal is performed by the control unit 70.
According to the toner transport device of the present invention, for example, by the above-described device configuration, the toner and air are mixed in the toner mixing unit to form a toner fluid, and the toner fluid is transported to the toner separating unit by the first transport unit. The toner separation unit separates the toner fluid into toner and air, supplies the toner to a developing device, etc., conveys the air to the toner mixing unit, and uses the air again for mixing with the toner. The channel is a closed ring channel.
[0055]
With such a configuration, the toner transport device of the present invention requires energy required to introduce air into the transport device when transporting the toner fluid and energy required to discharge air from the filter, as in the related art. Since the transfer of toner is not performed, the toner transfer efficiency of the first transfer unit is improved, and the toner can be transferred over a long distance. Further, the toner transport device of the present invention does not use a filter in the conventional toner transport, so that clogging of the filter does not occur and stable toner transport is possible.
[0056]
The control of the control unit 70 of the toner conveying device of the present invention will be described with reference to the block diagrams and flowcharts of FIGS.
[0057]
As shown in FIG. 6, the control unit 70 controls the motor 39b to operate at a set rotation number based on the transport signal so as to introduce the toner into the toner mixing chamber 35. Further, the control unit 70 controls the motor 55 a of the pump 501 to operate at the set number of revolutions to transport the toner fluid from the toner mixing chamber 35, and further controls the pump to transport air from the toner separation chamber 60. Control for operating the motor 55b of 502 at the set number of rotations is performed.
[0058]
The control unit 70 also actually detects the rotation speed of the motor 55b of the pump 501. This is because the rotation speed of the motor 55a of the pump 501 that actually conveys the toner fluid tends to be lower than the set rotation speed of the motor due to the load of the toner fluid. Since the load due to the toner fluid always fluctuates even in environmental conditions (temperature, humidity, etc.), it is accurate to detect the load each time.
[0059]
Next, a description will be given with reference to the flowchart of FIG.
The control unit 70 first activates the motor 39b of the toner inlet 34, the motor 55a of the pump 501, and the motor 55b of the pump 502 to start the transfer of the toner fluid (S-1).
[0060]
The controller 70 detects the actual amount of toner fluid conveyed by the pump 501 by detecting the number of rotations of the motor 55a of the pump 501 (S-2).
[0061]
The control unit 70 controls the rotation speed of the motor 55b of the pump 502 based on the detected transport amount of the toner fluid by the pump 501 (S-3).
[0062]
This control is for minimizing the difference between the pressure states of the toner mixing chamber 35 and the toner separation chamber 60 during toner conveyance, whereby the toner fluid can be stably conveyed.
[0063]
In this case, it is more preferable that the control unit 70 controls the rotation speed of the motor of the pump 502 so that the ratio of the detected transport amount of the toner fluid to the transport amount of the air of the second transport unit is constant. This eliminates the difference between the pressure states of the toner mixing chamber 35 and the toner separation chamber 60 during toner conveyance, and allows the toner fluid to be more stably conveyed.
[0064]
Further, the controller 70 determines whether or not the transport amount of the toner fluid has reached the target transport amount (S-4).
[0065]
The target transport amount is a predetermined amount of the toner fluid transported by the first transport unit, and is usually set at a value based on a required minimum amount of toner transported per unit time.
[0066]
If the transport amount of the toner fluid has not reached the target transport amount, control is performed to increase the rotation speed of the motor 55b of the pump 502 (S-5).
[0067]
As a result, the pressure of the toner mixing chamber 35 becomes higher than the pressure of the toner separation chamber 60, so that the toner fluid is pushed from the toner mixing chamber 35 to the pump 501 by a pressure difference. Therefore, the toner fluid is easily transported to the toner separation chamber 60, and the transport efficiency of the toner fluid by the pump 501 can be further improved.
[0068]
This control is very effective when the number of revolutions of the motor 55a of the pump 501 reaches the upper limit and the number of revolutions cannot be further increased. The source is used to transport toner fluid.
[0069]
The controller 70 detects the transport amount of the toner fluid by detecting the rotation speed of the motor 55a of the pump 501 again (S-6), and determines whether the transport amount of the toner fluid has reached the target transport amount. Is determined (S-7).
[0070]
When the toner transport amount has reached the target transport amount, the control unit 70 performs control to fix the rotation speed of the motor 55a of the pump 501 and the motor 55b of the pump 502 (S-9). If the toner transport amount has not reached the target transport amount, control is performed to stop the motor 39b of the inlet 34, the motor 55a of the pump 501, and the motor 55b of the pump 502, or a warning unit (not shown) A warning is issued to the user by a lamp or the like (S-8). If the toner transport amount has not reached the target transport amount, S-4 to S-6 are repeated again to further increase the number of rotations of the motor of the pump 502 to reach the target transport amount. Such control may be performed.
[0071]
Further, the control unit 70 controls the number of rotations of the motor 39b of the toner introduction port 34 to control the amount of toner supplied to the toner mixing chamber 35 based on the amount of toner fluid transported by the pump 501. Accordingly, the toner used as the toner fluid at the time of toner conveyance can be set to an appropriate amount, so that more stable toner conveyance becomes possible.
[0072]
Further, the control unit 70 controls the number of rotations of a motor (not shown) of the toner discharge port 68 based on the amount of toner fluid transported by the pump 501 to control the amount of toner discharged from the toner separation chamber 60.
[0073]
Further, it is preferable that the toner mixing chamber 35 and the toner separation chamber 60 have a toner detecting unit such as a toner sensor 33 using a piezo element, for example. When the toner amount detecting means detects that a predetermined amount or more of toner has accumulated in the motor 39b, the motor 39b, the motor 55a, and the motor 55b are controlled to be stopped, or a warning means (buzzer, lamp, or the like) (not shown) is used. It is preferable to perform control to give a warning to the user.
[0074]
【The invention's effect】
According to the present invention, it is possible to provide a toner conveying device capable of stably transporting toner over a long distance for a long period of time and an image forming apparatus using the toner conveying device.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an example of an image forming apparatus having a toner conveying device according to the present invention.
FIG. 2 is a diagram illustrating an example of a toner conveying device according to the present invention.
FIG. 3 is a diagram illustrating an example of a toner conveying device according to the present invention.
FIG. 4 is a diagram illustrating an example of a toner conveying device according to the present invention.
FIG. 5 is a diagram for explaining an example of the toner conveying device of the present invention.
FIG. 6 is a block diagram illustrating an example of control of the toner conveying device of the present invention.
FIG. 7 is a flowchart illustrating an example of control of the toner conveying device of the present invention.
[Explanation of symbols]
30 toner hopper 31 toner container 34 toner inlet 35 toner mixing chamber 40, 41, 42, 43 transport tube 60 toner separation chamber 68 toner outlet 501, 502 pump

Claims (8)

A toner transport device that transports toner,
Having at least a toner mixing unit, a toner separation unit, a first transport unit, and a second transport unit;
The toner mixing section has a toner introduction section for introducing toner, and mixes air with the toner introduced from the toner introduction section to form a toner fluid,
The first transporting unit transports the toner fluid of the toner mixing unit from the toner mixing unit to the toner separation unit,
The toner separation unit has a toner discharge unit that separates the toner fluid transported by the first transport unit into air and toner, and further discharges the toner to the outside,
The second conveying unit conveys the air separated by the toner separating unit from the toner separating unit to the toner mixing unit,
A toner circulation path is formed, in which a closed air flow path from the toner mixing section to the toner separation section via the first conveyance section, returns to the toner mixing section via the second conveyance section, and is formed again. apparatus. 2. The toner according to claim 1, further comprising a control unit configured to detect a transport amount of the toner fluid of the first transport unit and control a transport amount of the air of the second transport unit based on the transport amount. 3. Transport device. The control unit detects a transport amount of the toner fluid of the first transport unit, and performs control for keeping a ratio of the transport amount and an air transport amount of the second transport unit constant. Item 3. The toner conveying device according to Item 2. The control unit detects a transport amount of the toner fluid of the first transport unit, and performs control to increase an air transport amount of the second transport unit when the transport amount is equal to or less than a target transport amount. The toner conveying device according to claim 2, wherein: The control unit detects a transport amount of the toner fluid of the first transport unit, and when the transport amount is equal to or less than a target transport amount, performs control to stop the first transport unit and the second transport unit. 3. The toner conveying device according to claim 2, wherein: It has a warning means for giving a warning,
3. The control unit according to claim 2, wherein the control unit detects a transport amount of the toner fluid of the first transport unit, and performs a warning by the warning unit when the transport amount is equal to or less than a target transport amount. 4. The toner conveying device according to claim 1. The toner according to any one of claims 2 to 6, wherein the control unit controls the toner introduction amount of the toner introduction unit based on a toner fluid conveyance amount of the first conveyance unit. Transport device. An image forming apparatus comprising the toner conveying device according to claim 1.

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