JP2022069869A - Image forming apparatus - Google Patents

Abstract

To provide an image forming apparatus capable of reducing a frequency of vibrating a supply path with a vibration motor.SOLUTION: An image forming apparatus includes: a vibration device 57 for vibrating a supply path 51; first means for acquiring a toner residual amount of a toner container 27; second means 59 for detecting a toner concentration of a developing device 33; a conveyance member 55; and a control unit. The control unit executes normal supply if a toner concentration detected by the second means 59 is lower than a threshold value but not lower than a target value that is lower than the threshold value. However, if a toner concentration detected by the second means 59 is lower than the target value, and a toner residual amount acquired by the first means is larger than a residual amount for which it is determined that exchange of the toner container 27 is required, the control unit executes first forced supply during which the conveyance member 55 is driven to convey toner from the toner container 27 to the developing device 33, and during which the vibration device 57 vibrates the supply path 51 using a force stronger than at the time of normal supply.SELECTED DRAWING: Figure 2A

Description

The present invention relates to an image forming apparatus including a supply path for supplying toner from a toner container to a developing apparatus.

Toner is replenished from the toner container to the developing device If the supply path is clogged with toner or a lump of toner is formed, the concentration may be poor due to the lack of toner in the developing device, or the sensor that detects the empty state of the toner container may malfunction. Occur. Therefore, various methods for preventing toner clogging in the supply path have been proposed.

For example, in Patent Document 1, a temperature detecting means is provided in a developer storage container (toner container), and an image of vibrating the vibrating means provided in the developing agent storage container based on the temperature information detected by the temperature detecting means. The forming apparatus is described. Further, Patent Document 2 includes a powder stirring means for stirring powder in a powder / granular material container (toner container), and is used as a detection result of the powder amount detecting means for detecting the amount of powder in the powder / granular material container. Based on this, a powder replenishing device for operating the powder stirring means is described. By vibrating means or powder stirring means, the clogged toner or toner lumps are released.

Japanese Unexamined Patent Publication No. 2008-152093 Japanese Unexamined Patent Publication No. 2014-199395

However, when the toner container is vibrated or the toner in the toner container is agitated by the vibrating means or the powder stirring means as described above, the timing of executing these becomes a problem. If it is executed during the developing operation (image forming operation), it may affect the formed image. On the other hand, when the execution is performed other than during the development operation, problems such as deterioration of members and generation of noise occur, so it is preferable that the execution frequency is as low as possible.

In addition to temperature, factors such as temperature and pressure also affect the clogging of toner and the generation of lumps. Therefore, when predicting toner clogging from the detection result of the temperature detecting means as described in Patent Document 1, it may not be possible to vibrate the developer storage container at an appropriate timing. Further, in Patent Document 2, it is difficult to determine whether or not the state in which the amount of powder in the powder or granular material container is small is directly caused by the toner clogging.

Therefore, in view of the above circumstances, it is an object of the present invention to provide an image forming apparatus capable of reducing the frequency of vibrating the supply path.

The image forming apparatus according to the present invention includes a vibrating device that vibrates a supply path from a toner container to a developing device, a first means for acquiring the remaining amount of toner in the toner container, and a first means for detecting the toner concentration of the developing device. The two means, a transport member that transports toner from the toner container to the developing device via the supply path, control of driving of the vibrating device and the transport member, and from the first means and the second means. Each of the control unit includes a control unit for inputting a toner remaining amount value and a toner concentration, and the control unit has a toner concentration detected by the second means lower than a threshold value and lower than a target value lower than the threshold value. If it is not low, normal replenishment is performed in which the toner container is driven to transport toner from the toner container to the developing device, and the toner concentration detected by the second means is lower than the target value. Moreover, when the remaining amount of toner acquired by the first means is larger than the remaining amount of the toner container determined to be replaced, the transport member is driven to move from the toner container to the developing device. It is characterized in that the first forced replenishment that conveys the toner and drives the vibrating device is executed.

In the image forming apparatus of the present invention, in the control unit, the toner concentration detected by the second means is lower than the target value, and the remaining amount of toner acquired by the first means is the toner container. If the remaining amount is not more than the remaining amount determined to require replacement, the second forced replenishment may be performed by driving the transfer member to transfer the toner from the toner container to the developing device. ..

In the image forming apparatus of the present invention, the control unit may be characterized in that the vibration device is stopped at the time of the normal replenishment and the second forced replenishment, and the vibration device is driven at the time of the first forced replenishment.

In the image forming apparatus of the present invention, the control unit stops the vibration device at the time of the normal replenishment, drives the vibration device at the time of the second forced replenishment, and at the time of the first forced replenishment, at the time of the second forced replenishment. It may be characterized in that the vibrating device is driven so as to vibrate the supply path with a stronger force.

In the image forming apparatus of the present invention, the control unit drives the vibration device at the time of the normal replenishment and the second forced replenishment, and at the time of the first forced replenishment, from the time of the normal replenishment and the time of the second forced replenishment. It may be characterized in that the vibrating device is driven so as to vibrate the supply path with a strong force.

According to the present invention, the frequency of vibrating the supply path can be reduced by driving the vibrating device at an appropriate timing.

It is a front view which shows typically the internal structure of the image forming apparatus which concerns on one Embodiment of this invention. It is a figure which shows typically the toner replenishing apparatus of the image forming apparatus which concerns on one Embodiment of this invention. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 2A. It is a block diagram which shows the control part of the image forming apparatus which concerns on one Embodiment of this invention. It is a flowchart which shows an example of the toner forced supply operation of the image forming apparatus which concerns on one Embodiment of this invention. It is a graph which shows the result of the container remaining amount evaluation test in the conventional example. It is a graph which shows the result of the container remaining amount evaluation test in an Example. It is a graph which shows the result of the container remaining amount evaluation test in the comparative example. It is a graph which shows the driving time of the vibration motor in the image forming apparatus which concerns on one Embodiment of this invention.

Hereinafter, the image forming apparatus according to the embodiment of the present invention will be described with reference to the accompanying drawings.

The configuration of the image forming apparatus 1 will be described with reference to FIG. FIG. 1 is a front view schematically showing the internal configuration of the image forming apparatus 1. The front side of the paper surface in FIG. 1 is the front side (front side) of the image forming apparatus 1. L and R in each figure indicate the left side and the right side of the image forming apparatus 1, respectively.

The image forming apparatus 1 passes through the paper feeding unit 3, the toner image forming unit 5, the transfer unit 7, the fixing unit 9, the paper ejection unit 11, and the paper feeding unit 3 to the transfer unit 7 and the fixing unit 9. A paper transport path 13 toward the paper ejection unit 11 and a control unit 15 are provided. These are housed in the housing 17.

The paper feed unit 3 is provided at the lower part of the housing 17, and includes a paper feed cassette 19 for accommodating paper and a paper feed device 21 for feeding paper from the paper feed cassette 19 to the transport path 13.

The toner image forming unit 5 is provided above the feeding unit 3 and is arranged side by side with the exposure device 23 in four colors (Y (yellow), M (magenta), C (cyan), B ( It includes four toner image forming units 25 corresponding to the toner of black))) and four toner containers 27 containing four color toners.

Each toner image forming unit 25 includes a rotatable photoconductor drum 29, a charging device 31 which is sequentially arranged around the photoconductor drum 29 along the rotation direction of the photoconductor drum 29, a developing device 33, and a cleaning device. 35 and.

The charging device 31 charges the photoconductor drum 29 to a predetermined potential. When the charged photoconductor drum 29 is exposed by the exposure apparatus 23, an electrostatic latent image is formed on the photoconductor drum 29. The developing device 33 develops an electrostatic latent image of the photoconductor drum 29 into a toner image with a two-component developer composed of a toner and a carrier. The cleaning device 35 removes the toner remaining on the photoconductor drum 29.

Toner is replenished from the toner container 27 containing the toner of the corresponding color to the developing device 33 by the toner replenishing device 37 (see FIG. 2). The toner replenishing device 37 will be described later.

The transfer unit 7 includes an intermediate transfer belt 41, four primary transfer rollers 43, and a secondary transfer roller 45. The intermediate transfer belt 41 is arranged above the four toner image forming units 25 and circulates in a predetermined direction. The four primary transfer rollers 43 are arranged in the hollow portion of the intermediate transfer belt 41 and face the photoconductor drums 29 of the four toner image forming units 25 with the intermediate transfer belt 41 interposed therebetween. Each primary transfer roller 43 transfers the toner image formed on the photoconductor drum 29 of the corresponding toner image forming unit 25 to the intermediate transfer belt 41. As a result, a full-color image is formed on the intermediate transfer belt 41. The secondary transfer roller 45 contacts the intermediate transfer belt 41 to form a transfer nip between them. The secondary transfer roller 45 transfers the full-color image of the intermediate transfer belt 41 to the paper fed to the transfer path 13 by the paper feed device 21 at the transfer nip.

The fixing portion 9 is arranged above the transfer portion 7. The fixing unit 9 fixes the full-color toner image secondarily transferred to the paper to the paper.

The paper ejection unit 11 is arranged above the fixing portion 9, and is an ejection device 47 arranged inside an ejection port formed on the upper wall of the housing 17, and an ejection tray formed on the upper surface of the housing 17. It has 49 and. The discharge device 47 discharges the paper from the transport path 13 through the discharge port. Paper discharged by the discharge device 47 is loaded on the discharge tray 49.

Next, the toner replenishing device 37 will be described with reference to FIGS. 2A and 2B. 2A is a diagram schematically showing a toner replenishing device, and FIG. 2B is a sectional view taken along line II-II of FIG. 2A.

The toner replenishment device 37 includes a replenishment path 51 to which toner is supplied from the toner container 27, a rotation mechanism 53 for rotating the toner container 27, a transfer screw 55 for transporting toner from the replenishment path 51 to the developing device 33, and a replenishment path. It includes a vibration motor 57 that vibrates 51, and a magnetic permeability sensor 59 that measures the magnetic permeability of the developer in the developing apparatus 33.

The toner container 27 has a bottle shape and has a cylindrical main body 61 and a cap 63 having a diameter smaller than that of the main body 61. The main body 61 and the cap 63 can rotate independently of each other. A spiral protrusion 61a protruding inward is formed on the inner peripheral surface of the main body 61. A discharge port 63a is formed on the side wall of the cap 63.

The toner container 27 is arranged in a sideways posture with the discharge port 63a of the cap 63 facing downward, and the cap 63 is non-rotatable and the main body 61 is rotatably supported by the toner container mounting portion.

The rotation mechanism 53 includes a drive gear 65 that engages with the main body 61 of the toner container 27, and a replenishment motor 67 that rotates the drive gear 65. When the replenishment motor 67 is driven to rotate the drive gear 65, the main body 61 of the toner container 27 rotates with respect to the cap 63, and the toner contained in the main body 61 is provided by the spiral protrusion 61a formed on the main body 61. Is transported toward the cap 63. The toner falls through the discharge port 63a of the cap 63. As described above, the spiral protrusion 61a is an example of a transport member that transports toner from the toner container 27 to the developing device 33 via the supply path 51.

The supply path 51 is arranged below the toner container 27, and has a storage portion 51a along the vertical direction, a lateral transport portion 51b having one end communicating with the lower end of the storage portion 51a and extending along the horizontal direction, and a lateral transport portion. It has a vertical transport portion 51c that communicates with the other end of the 51b and extends downward along the vertical direction. The upper end opening of the storage portion 51a is arranged below the discharge port 63a of the cap 63 of the toner container 27. The lower end opening of the vertical transport portion 51c is connected to the toner supply port of the developing device 33.

The transport screw 55 is rotatably supported by the lateral transport portion 51b of the supply path 51. The transfer screw 55 is driven by the transfer motor 69 and rotates. By the rotation of the transfer screw 55, the toner in the horizontal transfer section 51b is conveyed toward the vertical transfer section 51c. As described above, the transport screw 55 is an example of a transport member that transports toner from the toner container 27 to the developing device 33 via the supply path 51.

As shown in FIG. 2B, the vibration motor 57 is attached to the outer surface of the lateral transport portion 51b of the supply path 51. By vibrating the vibration motor 57, the lateral transport portion 51b vibrates, and the fluidity of the toner contained in the lateral transport portion 51b is enhanced. As a result, when the toner is clogged or lumped in the lateral transport portion 51b, the clogged toner or the lump of toner can be unpacked. As described above, the vibration motor 57 is an example of a vibration device that applies a vibration force to the supply path 51.

In this embodiment, for the sake of clarity, a case where one vibration motor 57 is attached to one toner replenishing device 37 will be described as shown in FIG. 2A. In a full-color image forming apparatus as in the present embodiment, for example, a horizontal transport path of a supply path of two adjacent toner supply devices is connected by a sheet metal member, a vibration motor is attached to the sheet metal member, and two vibrations are further formed. The motor may be electrically connected. In this case, by driving the vibration motor, it is possible to simultaneously vibrate the lateral transport paths of the replenishment paths of the four toner replenishment devices via the sheet metal member.

The magnetic permeability sensor 59 is arranged in the developer accommodating portion of the developing apparatus 33, and measures the toner / carrier abundance ratio (T / C) in the developer accommodating portion. The magnetic permeability sensor 59 is an example of a second means for detecting the toner concentration of the developing device 33.

Next, the control unit 15 will be described with reference to the block diagram of FIG.

The control unit 15 is electrically connected to the replenishment motor 67, the transfer motor 69, and the vibration motor 57 to control the drive and stop of these motors. Further, the control unit 15 is electrically connected to the magnetic permeability sensor 59, and the detection result of the magnetic permeability sensor 59 is input. The control unit 15 calculates the toner / carrier abundance ratio (T / C) of the developer accommodating unit of the developing device 33 from the detection result.

Further, the control unit 15 is provided with a toner remaining amount prediction unit 71 of the toner container 27. The toner remaining amount prediction unit 71 counts the number of dots per page of the output image and predicts the toner consumption. Then, the predicted toner consumption is subtracted from the toner filling amount of the toner container 27 to calculate the toner remaining amount Mt. The toner remaining amount prediction unit 71 is an example of the first means for acquiring the toner remaining amount of the toner container 27.

Further, the control unit 15 stores a target value Vtaget of the toner / carrier abundance ratio (T / C) of the developer accommodating unit of the developing device 33. The target value Vtaget is a value lower than the threshold value Vth of the toner / carrier abundance ratio of the developing device 33. Further, the control unit 15 stores the remaining amount of toner when it is determined that the toner container 27 needs to be replaced as the toner reference amount Mrow.

An example of the toner replenishment operation in the image forming apparatus 1 having the above configuration will be described with reference to the flowchart of FIG.

When the printing operation is started in step S1, the control unit 15 acquires the output value Vt of the magnetic permeability sensor 59 in step S2. After that, in step S3, the control unit 15 determines whether or not the output value Vt of the magnetic permeability sensor 59 is lower than the threshold value Vth. If the output value Vt is lower than the threshold value Vth, the control unit 15 determines that the toner replenishment operation is necessary, and proceeds to step S4. On the other hand, when the output value Vt of the magnetic permeability sensor 59 is not lower than the threshold value Vth, the control unit 15 repeats the above determination until the output value Vt of the magnetic permeability sensor 59 becomes lower than the threshold value Vth.

In step S4, the control unit 15 determines whether the output value Vt is lower than the target value Vtaget. If it is determined that the output value Vt is not lower than the target value Vtaget, the control unit 15 proceeds to step S5 and executes a normal replenishment operation.

In step S5, the control unit 15 drives the replenishment motor 67 to rotate the main body 61 of the toner container 27 to transfer the toner from the toner container 27 to the replenishment path 51 while continuing the printing operation, and the transfer motor 69. To rotate the transfer screw 55 to transfer toner from the supply path 51 to the developing device 33. In this way, the normal replenishment operation is executed in parallel with the printing operation. Further, the vibration motor 57 is stopped during normal replenishment.

On the other hand, if it is determined in step S4 that the output value Vt is lower than the target value Vtaget, the control unit 15 determines that the forced toner supply operation is necessary and proceeds to step S6. The forced replenishment operation is an operation of stopping the printing operation (in the case of continuous printing, stopping continuous printing) and replenishing the toner. During the forced replenishment operation, even if the next print command is input, the next print command is not executed until the forced replenishment operation is completed.

In step S6, the control unit 15 acquires the toner remaining amount Mt predicted by the toner remaining amount prediction unit 71, and proceeds to step S7. In step S7, the control unit 15 determines whether or not the predicted toner remaining amount Mt is larger than the toner reference amount Mlow (for example, 15 g). If it is determined that the toner remaining amount Mt is larger than the toner reference amount Mlow, the process proceeds to step S8.

In step S8, the control unit 15 stops the printing operation (in the case of continuous printing, stops continuous printing), drives the replenishment motor 67 to rotate the main body 61 of the toner container 27, and from the toner container 27. The toner is conveyed to the supply path 51, and the transfer motor 69 is driven to rotate the transfer screw 55 to transfer the toner from the supply path 51 to the developing device 33. Further, the vibration motor 57 is driven to vibrate the supply path 51. The above replenishment operation is referred to as the first compulsory replenishment.

In the state of step S8, the output value Vt of the magnetic permeability sensor 59 is lower than the target value Vtaget, and the toner is not sufficiently replenished to the developing device 33 even though the normal replenishment operation is performed. It is shown that. On the other hand, the state of step S8 also indicates that the toner remaining amount Mt of the toner container 27 is larger than the toner reference amount Mlow, and the toner container 27 is not empty. That is, it indicates that the toner container 27 is not empty and the toner amount of the developing device 33 is small even though the toner can be replenished by the normal replenishment operation, and the detection result of the magnetic permeability sensor 59 and the toner residue are shown. It can be said that the prediction result of the quantity prediction unit 71 is inconsistent. It is presumed that this is because toner is not sufficiently supplied from the supply path 51 to the developing device 33 due to toner clogging or formation of toner lumps in the supply path 51.

Therefore, in this case, the vibration motor 57 is driven to vibrate the lateral transport portion 51b of the supply path 51 to release the clogged toner or the toner lump. As a result, the toner supplied to the supply path 51 (including the dissolved toner) can be reliably transported to the developing device 33 by the transport screw 55. The vibration motor 57 vibrates for a predetermined time.

On the other hand, if it is determined in step S7 that the remaining amount of toner Mt is not larger than the toner reference amount Mlow, the process proceeds to step S9.

In step S9, the control unit 15 stops the printing operation (stops continuous printing in the case of continuous printing), drives the replenishment motor 67 to rotate the main body 61 of the toner container 27, and causes the toner container 27. Toner is transferred from the supply path 51 to the supply path 51, and the transfer motor 69 is driven to rotate the transfer screw 55 to transfer the toner from the supply path 51 to the developing device 33. In this case, the vibration motor 57 is not operated. The above replenishment operation is referred to as the second compulsory replenishment.

Step S9 indicates a state in which the output value Vt is lower than the target value Vtaget, in other words, the T / C of the developing device 33 is low, so that the replenishment motor 67 and the transfer motor 69 are driven from the toner container 27. Toner is forcibly transferred to the developing device 33. Further, the remaining amount of toner Mt of the toner container 27 is not larger than the reference amount of toner Mlow, indicating that the toner container 27 is almost empty. That is, since the toner container 27 is almost empty, the amount of toner supplied to the developing device 33 is small, which is a natural result. This indicates that the toner is reliably replenished from the toner container 27 to the developing device 33 in the normal replenishment operation, and it is predicted that no toner clogging has occurred in the replenishment path 51, so that the vibration motor 57 is driven. You don't have to let it.

After that, the process proceeds to step S10 to drive the replenishment motor 67 and the transfer motor 69 for a predetermined time, and then the process proceeds to step S11 to stop the replenishment motor 67 and the transfer motor 69.

If the toner concentration of the developing device 33 does not increase even after the forced replenishment operation is executed, the control unit 15 determines that the toner container 27 needs to be replaced, and displays the operation panel (not shown) or the like. Display a message. As described above, the forced replenishment operation is also a means for determining whether or not the toner container 27 needs to be replaced. If the accuracy of the toner remaining amount Mt predicted by the toner remaining amount prediction unit 71 is sufficiently high, the determination by the forced replenishment operation is not necessary, but the toner remaining amount Mt predicted by the toner remaining amount prediction unit 71 is Since it varies to some extent depending on the type of printed matter (characters, graphics) and the installation environment of the image forming apparatus 1, it is preferable to determine whether or not the toner container 27 needs to be replaced in accordance with the forced replenishment operation.

As is clear from the above description, according to the image forming apparatus 1 of the present embodiment, when the toner container 27 is not empty but the toner is not replenished from the toner container 27 to the developing apparatus 33, the replenishment path is used. Since it is determined that toner clogging has occurred in 51, the accuracy of determining toner clogging can be improved. Then, only in this case, the replenishment operation is executed and the vibration motor 57 is driven. As a result, the frequency with which the supply path 51 is vibrated by the vibration motor 57 can be reduced as much as possible.

Further, the forced replenishment is divided into the first forced replenishment and the second compulsory operation by using the remaining amount of toner Mt, and at the time of the second forced replenishment, only the toner is replenished and the vibration motor 57 is not vibrated. The frequency of vibrating the supply path 51 can be further reduced.

Further, since the control unit 15 stops the vibration motor 57 during normal replenishment and during the second forced replenishment and drives the vibration motor 57 only during the first forced replenishment, the frequency of vibrating the supply path 51 with the vibration motor 57. Can be further reduced.

If the environment is such that the toner tends to aggregate or the toner tends to aggregate, the control unit 15 stops the vibration motor 57 during normal replenishment and the vibration motor 57 during the second forced replenishment. May be driven, and the vibration motor 57 may be driven so as to vibrate the supply path 51 with a stronger force at the time of the first forced replenishment than at the time of the second forced replenishment. Alternatively, the control unit 15 drives the vibration motor 57 during the normal replenishment and the second forced replenishment, and vibrates the replenishment path 51 at the time of the first forced replenishment with a stronger force than at the time of the normal replenishment and the second forced replenishment. The vibration motor 57 may be driven as described above. Even in such a case, the frequency of vibrating the supply path 51 with the vibration motor 57 can be reduced.

The method (first means) for acquiring the remaining amount of toner in the toner container 27 is not limited to the above embodiment, and for example, the remaining amount of toner may be acquired from the number of rotations of the toner container 27. Further, the method (second means) of detecting the presence or absence of toner supply from the toner container 27 to the developing device 33 is not limited to the above embodiment, and for example, the reflection concentration of the developing agent carried on the magnet roller of the developing device 33. The toner concentration of the developer of the developing device 33 may be obtained from the above, and the presence or absence of toner supply may be detected. However, the method described in the above embodiment is general and is preferable in terms of cost.

Further, when the supply paths 51 of the four toner replenishment devices 37 are vibrated at the same time, when the clogging of the toner or the generation of the toner lump is detected in any of the toner replenishment devices 37, all the toner replenishment devices 37 The supply path 51 is vibrated.

Next, the test results of evaluating the remaining amount of toner in the toner container 27 when the toner forced replenishment operation of the present embodiment is performed will be described with reference to the graphs of FIGS. 5A to 5C. In nine toner containers, the remaining amount of toner at the time of toner container replacement (when it was determined that the toner container was empty) when the toner forced replenishment operation was performed by a predetermined experimental machine was evaluated. An example in which the forced replenishment operation of the present embodiment is performed, an example in which the replenishment path 51 is not vibrated during the forced replenishment operation, and a comparative example in which the replenishment path 51 is vibrated by the vibration motor 57 in all the forced replenishment operations. And. The vertical axis of each graph shows the frequency (number of toner containers (lines)), and the horizontal axis shows the remaining amount of containers (g). 5A shows a conventional example, FIG. 5B shows an embodiment, and FIG. 5C shows a comparative example.

When the remaining amount of the container is large, it means that all the toner supplied from the toner container 27 to the supply path 51 is not surely supplied to the developing device 33 in the normal replenishment operation. Indicates that there is a high possibility that toner clogging or toner lumps have occurred. Generally, the remaining amount of the container is preferably 15 g or less.

In the conventional example shown in FIG. 5A, the remaining amount of the two toner containers is 21 g or more, and it can be seen that the toner clogging and the toner lumps generated in the supply path 51 have not been eliminated.

In the embodiment shown in FIG. 5B, the remaining amount of the container is 15 g or less in all the toner containers, and by driving the vibration motor 57, the toner clogging and the toner lumps generated in the supply path 51 are eliminated. You can see that it is.

Also in the comparison shown in FIG. 5C, the remaining amount of the container is 15 g or less in all the toner containers, and by driving the vibration motor 57, the toner clogging and the toner lump generated in the supply path 51 are eliminated. You can see that it is.

Next, with reference to the graph of FIG. 6, the drive time of the vibration motor 57 in each example during the toner replenishment operation will be described. The vertical axis of the graph shows the total vibration time (sec).

In the case of the example, the total vibration time is as short as about 1/6 of the comparative example. That is, it is shown that even if the vibration time is short as in the embodiment, it is possible to reduce the remaining amount of toner by vibrating only when necessary.

The description of the above embodiment shows one aspect of the image forming apparatus according to the present invention, and the technical scope of the present invention is not limited to the above embodiment.

1 Image forming device 15 Control unit 27 Toner container 33 Developing device 51 Supply path 55 Conveying screw (conveying member)
57 Vibration motor (vibration device)
59 Permeability sensor (second means)
61a Protrusion (conveying member)
71 Toner remaining amount prediction unit (first means)

Claims (5)

A vibrating device that vibrates the supply path from the toner container to the developing device,
The first means for acquiring the remaining amount of toner in the toner container and
A second means for detecting the toner concentration of the developing device and
A transport member that transports toner from the toner container to the developing device via the supply path, and
It is provided with a control unit that controls the drive of the vibrating device and the transport member, and inputs the toner remaining amount value and the toner concentration from the first means and the second means, respectively.
The control unit
When the toner concentration detected by the second means is lower than the threshold value and not lower than the target value lower than the threshold value, the transfer member is driven to transfer the toner from the toner container to the developing device. Perform normal replenishment,
The toner concentration detected by the second means is lower than the target value, and the remaining amount of toner acquired by the first means is larger than the remaining amount determined to require replacement of the toner container. In the case of an image forming apparatus, the image forming apparatus is characterized in that the transport member is driven to transport toner from the toner container to the developing device and the first forced replenishment for driving the vibration device is executed. The control unit determines that the toner concentration detected by the second means is lower than the target value and the remaining amount of toner acquired by the first means requires replacement of the toner container. The image forming apparatus according to claim 1, wherein when the amount is not more than the remaining amount, the second forced replenishment for driving the transfer member to transfer toner from the toner container to the developing device is executed. .. The image forming apparatus according to claim 2, wherein the control unit stops the vibration device at the time of the normal replenishment and the second forced replenishment, and drives the vibration device at the time of the first forced replenishment. The control unit stops the vibration device at the time of the normal replenishment, drives the vibration device at the time of the second forced replenishment, and at the time of the first forced replenishment, the replenishment path with a stronger force than at the time of the second forced replenishment. The image forming apparatus according to claim 2, wherein the vibrating device is driven so as to vibrate. The control unit drives the vibration device at the time of the normal replenishment and the second forced replenishment, and at the time of the first forced replenishment, the replenishment path is operated with a stronger force than at the time of the normal replenishment and the second forced replenishment. The image forming apparatus according to claim 2, wherein the vibrating device is driven so as to vibrate.

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