JP2007127824A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of preventing the overflow of developer to the utmost by appropriately controlling the quantity of the developer to be replenished to a developing apparatus. <P>SOLUTION: A continuance period of a state that the residual toner quantity in the developing apparatus is below a prescribed quantity and a continuance period of a state that the quantity is equal to or exceeding the prescribed quantity are counted, and in accordance with the counted period, a replenishing mode is switched between a first replenishment mode where the quantity of toner to be replenished to the developing apparatus is set as a first replenishing quantity which is equal to or below the consumption of the developer calculated based on an output image and a second replenishment mode where the quantity is set as a second replenishing quantity larger than the first replenishing quantity. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming apparatus that performs printing using a developer, and more particularly, to a technique for controlling the amount of developer replenished to a developing device provided in the image forming apparatus.

An image forming apparatus such as a copying machine or a printer device has a developing device that develops an electrostatic latent image formed on the surface of a photoconductive drum with toner, and a toner that is supplied from a toner storage unit that stores toner to the developing device. And a replenishing device for replenishing.
In the image forming apparatus, toner is supplied from the toner reservoir to the developing device by the supply device as necessary. For example, when it is detected that the remaining amount of toner in the developing device is less than a predetermined amount, replenishment of toner by the replenishing device is started, and the remaining amount of toner in the developing device exceeds the predetermined amount. In some cases, the supply is controlled to stop when it is detected (hereinafter referred to as a conventional method). In this conventional toner replenishment control, if it is detected that the remaining amount of toner in the developing device does not reach a predetermined amount even after a predetermined time has elapsed since the start of toner replenishment, Toner empty indicating that there is no toner in the toner reservoir is displayed. As a result, the user is urged to replace the toner reservoir and replenish toner to the toner reservoir.

However, the remaining amount detection sensor for detecting the remaining amount of toner in the developing device detects the remaining amount of toner at a specific installation position in the developing device. Even if the toner is replenished, the increase in toner may not be reflected in the detection result of the remaining amount detection sensor until the toner reaches the remaining amount detection sensor. Further, since the toner conveyed by the screw or the like in the developing device tends to be unevenly distributed, there is a limit to the accuracy in detecting the remaining amount of toner by the remaining amount detection sensor. For this reason, the detection of the saturation state of the toner in the developing device by the remaining amount detection sensor is delayed, and the replenishing device replenishes toner from the toner reservoir to the developing device more than necessary. The toner may overflow.
On the other hand, Japanese Patent Application Laid-Open No. 2004-133867 deals with the print rate of the output image in order to suppress the occurrence of toner overflow caused by the replenishment device replenishing toner from the toner reservoir to the developing device more than necessary. A method of supplying a smaller amount of toner than the amount of toner consumed is disclosed. However, since the toner in the developing device will be insufficient by merely replenishing a toner smaller than the amount of toner consumed corresponding to the print rate of the output image, the toner replenishment control by the conventional method is also used.
JP 2003-195623 A

However, since the image forming apparatus disclosed in Patent Document 1 replenishes a smaller amount of toner than the amount of toner consumed corresponding to the printing rate of the output image, it is necessary to reliably perform toner replenishment control by the conventional method. In the replenishment control, there is still a possibility that toner overflow may occur.
Accordingly, the present invention has been made in view of the above circumstances, and an object thereof is to prevent the occurrence of developer overflow as much as possible by appropriately controlling the amount of developer supplied to the developing device. An object of the present invention is to provide an image forming apparatus capable of performing the above.

To achieve the above object, the present invention provides a developing means for developing an electrostatic latent image formed on a predetermined image carrier with a developer, and a first means for detecting the remaining amount of the developer in the developing means. Residual amount detecting means, developer supplying means for supplying the developer to the developing means from the developer storing portion where the developer is stored, and consumption of the developer by the developing means based on the print rate of the output image And a developer consumption amount calculating unit that calculates the amount of time, and a time during which the detection result by the first remaining amount detecting unit is less than a predetermined amount continues. And a state timing function for measuring the time during which the state exceeding the predetermined amount continues, and for the developer replenishing means, the developer consumption calculated by the developer consumption calculating means is equal to or consumed by the developer consumption calculating means. A first replenishment amount less than the amount A second replenishment amount larger than the first replenishment amount is set based on a first replenishment control function for replenishing the stage and a time measured by the state timing unit, and the developer replenishing unit And a second replenishment control function for causing the developing means to replenish a second replenishment amount, and the first replenishment control function and the second replenishment control according to the time measured by the state timing function. It is configured to switch between functions.
According to the present invention, the first replenishment control function and the second replenishment control function are switched according to the time measured by the state timing function, and the developer replenishment amount by the developer replenishing means is changed. As a result, the remaining amount of the developer in the developing means can be properly maintained to prevent the developer overflow. Specifically, by selectively performing either the first supply amount or the second supply amount, the developer in the developing unit is insufficient and the developer according to the conventional method is used. Therefore, it is possible to prevent the overflow of the developer that occurs in the developer replenishment control according to the conventional method as much as possible.

By the way, the amount of the developer replenished from the developer reservoir to the developing unit by the developer replenishing unit varies depending on the remaining amount of developer stored in the developer reservoir. Specifically, when the remaining amount of developer in the developer reservoir is small, the amount of developer replenished from the developer reservoir to the developing unit is reduced. For this reason, for example, when the developer replenishing means adjusts the developer replenishment amount in accordance with the rotation amount of a predetermined motor, the rotation amount is determined in consideration of the remaining amount of developer in the developer reservoir. If the amount is not set, an appropriate amount of developer cannot be supplied to the developing means.
Therefore, it is desirable to detect the remaining amount of the developer in the developer reservoir and set the second supply amount based on the detection result and the time measured by the state time measuring means. For example, the second supply amount may be set to increase as the remaining amount of developer in the developer storage portion decreases. As a result, even when the remaining amount of developer in the developer reservoir is small, the second replenishment amount is set to be large, so that the developer replenishment amount to the developing means is maintained appropriately. Is done.
Further, as described above, in the conventional method, when it is detected that the remaining amount of the developer in the developing unit does not reach the predetermined amount even after a predetermined time has elapsed since the start of the supply of the developer. Is determined to be in a state where there is no developer in the developer reservoir (toner empty). Therefore, when the remaining amount of the developer in the developer reservoir decreases and the amount of developer supplied to the developer by the developer replenisher decreases, the developer reservoir actually has some developer in the developer reservoir. Even when the toner remains, it is detected that the remaining amount of the developer in the developing unit is less than the predetermined amount when a predetermined time has elapsed since the start of the replenishment of the developer. It is conceivable that it is erroneously determined. Therefore, for example, there is a problem that the toner empty is displayed to the user before the developer remaining in the developer reservoir is used up.
However, as described above, if the second supply amount is set to increase as the remaining amount of developer in the developer storing portion decreases, the remaining amount of developer in the developer storing portion decreases. In this case, the toner empty is not erroneously determined, and the developer remaining in the developer reservoir can be used up.

  In addition, when the time during which the detection result by the first remaining amount detecting means timed by the state time counting function is a predetermined amount or more continues for a predetermined time or longer, the second supply control function starts. It is desirable to switch to the first supply control function. As a result, it is possible to prevent the developer from overflowing due to replenishment of more developer than necessary.

According to the present invention, the first replenishment control function and the second replenishment control function are switched according to the time measured by the state timing function, and the developer replenishment amount by the developer replenishing means is changed. As a result, the remaining amount of the developer in the developing means can be properly maintained to prevent the developer overflow. Specifically, by selectively performing either the first supply amount or the second supply amount, the developer in the developing unit is insufficient and the developer according to the conventional method is used. Since it is possible to prevent the shift to the replenishment control as much as possible, it is possible to prevent the overflow of the developer that occurs in the developer replenishment control according to the conventional method as much as possible.
Further, by detecting the remaining amount of the developer in the developer reservoir, and setting the second supply amount based on the detection result and the time measured by the state timing unit, the developer to the developing unit is set. It becomes possible to maintain the replenishment amount appropriately. Further, it is possible to prevent erroneous determination of toner empty when the remaining amount of the developer in the developer storage portion is reduced.
In addition, when the time during which the detection result by the first remaining amount detecting means timed by the state time measuring function is a predetermined amount or more continues for a predetermined time or longer, the second supply control function starts. By switching to the first replenishment control function, it is possible to prevent the developer from being replenished in the developing means and overflowing the developer.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings so that the present invention can be understood. The following embodiment is an example embodying the present invention, and does not limit the technical scope of the present invention.
FIG. 1 is a block diagram showing a schematic configuration of a printer X according to an embodiment of the present invention, FIG. 2 is a schematic cross-sectional view showing a peripheral configuration of a developing device 42 provided in the printer X, and FIG. FIG. 4 is a flowchart for explaining an example of the procedure of toner replenishment processing executed in the printer X. FIG.
First, a schematic configuration of the printer X according to the embodiment of the present invention will be described with reference to the block diagram of FIG. The printer X is merely an example of an image forming apparatus according to the present invention, and the present invention can be applied to an image forming apparatus such as a copying machine, a facsimile machine, or a multifunction machine thereof.
As shown in FIG. 1, the printer X comprises a CPU, a peripheral device such as a ROM and a RAM, and performs overall control of the printer X by executing processing according to a predetermined program stored in the ROM. Control unit 1, operation display unit 2 such as a liquid crystal display and a touch panel for performing display and input operations of various information in the printer X, a storage unit 3 for storing image data and the like, and a paper feed (not shown) An image forming unit 4 that executes an image forming process for forming an image on a sheet replenished from a cassette, and a communication processing unit 5 for performing communication with an external information processing apparatus Y via the LAN 10 are schematically provided. It is configured.
In the printer X, each component is controlled by the control unit 1, so that the communication processing unit 5 receives the image data from the information processing apparatus Y and stores it in the storage unit 3. Thus, print output by the image forming unit 4 is executed.

Next, a schematic configuration of the image forming unit 4 will be described with reference to FIG.
As shown in FIG. 2, the image forming unit 4 includes a photosensitive drum 41 (an example of a predetermined image carrier) on which an electrostatic latent image is formed on a surface by a charging device and an exposure device (not shown), and the photosensitive device. A developing device 42 (an example of developing means) that visualizes (develops) an electrostatic latent image formed on the surface of the body drum 41 with toner, which is a one-component developer, and replenishes the developing device 42 And a toner container 43 (an example of a developer storage unit) in which toner for storing is stored. The developer may be a two-component developer.

As shown in FIGS. 2 and 3, the developing device 42 rotates while being in contact with the photosensitive drum 41 to supply toner to the photosensitive drum 41, and replenished from the toner container 43. A toner replenishing port 52 for receiving the toner to be supplied, conveying rollers 53 and 54 made of a screw or the like for conveying the toner replenished from the toner replenishing port 52 in the direction of arrow R shown in FIG. And a photoelectric remaining amount detection sensor 55 (an example of a first remaining amount detecting unit) that detects the remaining amount of toner in the apparatus 42. The remaining amount of toner in the developing device 42 detected by the remaining amount detection sensor 55 is input to the control unit 1.
As shown in FIG. 2, the toner container 43 is rotationally driven by a drive motor (not shown) and drops the toner contained in the toner container 43 toward the toner supply port 52 of the developing device 42 to supply the toner container 43. A replenishing roller 61 (an example of a developer replenishing unit), a stirring roller 62 that stirs the toner stored in the toner container 43 and scrapes the toner toward the replenishing roller 61, and the toner in the toner container 43. A photoelectric remaining amount detecting sensor 63 (an example of second remaining amount detecting means) that detects the remaining amount. The remaining amount of toner in the toner container 43 detected by the remaining amount detection sensor 63 is input to the control unit 1.

In the printer X configured in this way, an amount of toner corresponding to the print rate of the output image printed out by the image forming unit 4 is consumed in the developing device 42. The toner consumption corresponding to the printing rate of the output image is calculated by the control unit 1 based on the printing rate of the output digital image every time the image forming process is executed. Here, the control unit 1 when executing such calculation processing corresponds to the developer consumption calculating means.
In the printer X, when the cumulative amount of toner consumption reaches a predetermined consumption amount (hereinafter referred to as “replenishment consumption amount”), and the remaining amount of toner in the developing device 42 is less than the predetermined amount. The controller 1 controls the driving of the replenishing roller 61 to replenish toner in the developing device 42.

Here, the amount of toner supplied from the toner container 43 to the developing device 42 is adjusted by the rotation amount of the supply roller 61. In the following description, the replenishment roller 61 rotating for 2 seconds and stopping for 1.5 seconds is referred to as one toner replenishment. In the present embodiment, the toner replenishment process (see the flowchart of FIG. 4), which will be described later, is performed in step S2 by one replenishment of toner that is executed when sufficient toner remains in the toner container 43. It is assumed that an amount of toner equivalent to the predetermined replenishment consumption amount serving as a determination index is replenished. Note that a smaller amount of toner than the replenishment consumption may be replenished.
Conventionally, the amount of toner to be replenished is set to be equal to or smaller than the predetermined replenishment consumption amount, and the toner will surely run out, so toner overflow may occur. Therefore, it has been necessary to execute toner replenishment control by a conventional method.
However, in the printer X, a first replenishment consumption amount equal to or less than the predetermined replenishment consumption amount in a later-described toner replenishment process (see the flowchart of FIG. 4) executed by the control unit 1. The first replenishment mode for replenishing a replenishment amount of toner and the second replenishment mode for replenishing a second replenishment amount of toner that is greater than the first consumption amount are appropriately switched and executed. Since the toner in the developing device 42 is maintained at an appropriate amount, the necessity of executing toner replenishment control according to the conventional method is significantly reduced.

Hereinafter, an example of the procedure of toner replenishment processing executed by the control unit 1 in the printer X will be described with reference to the flowchart of FIG. In the figure, S1, S2,... Represent processing procedure (step) numbers.
The toner replenishment process is started by the control unit 1 when the printer X is turned on, for example, and is ended when the power is turned off. The parameters calculated or set in the toner replenishment process are stored or read by the control unit 1 in the RAM of the control unit 1 or the storage unit 3.
First, in step S1, the control unit 1 calculates the cumulative amount of toner consumption at that time and the average value of the printing rate calculated based on the printing rate of the output image printed by the printer X. Is done. Note that the toner consumption amount is calculated based on the printing rate of the output digital image each time the image forming process is performed by the control unit 1 as described above.
The process of step S1 is repeatedly executed until the control unit 1 determines that the cumulative amount of toner consumption is equal to or greater than the predetermined supply consumption in the subsequent step S2. If it is determined in step S2 that the cumulative amount of toner consumption is greater than or equal to the predetermined supply consumption, the process proceeds to step S3.

In step S3, the controller 1 determines whether or not the toner replenishment operation frequency n is less than 6. Here, the number n of toner replenishment operations is a factor that determines the amount of toner replenished from the toner container 43 to the developing device 42 in step S9, which will be described later, such as S4, S132, S133, which will be described later. As described above, when sufficient toner remains in the toner container 43 as described above, an amount equivalent to the predetermined replenishment consumption amount is replenished by one replenishment operation. The initial value of the toner replenishment operation count n is set to 0.
If it is determined that the toner replenishment operation number n is less than 6 (Yes in S4), the process proceeds to step S4, and the control unit 1 sets the toner replenishment operation number n to 1. It is set to increase (n = n + 1) times, and the process proceeds to step S5. That is, since it is determined in step S2 that the cumulative amount of toner consumption is larger than the predetermined replenishment consumption amount and at least the predetermined replenishment consumption amount of toner needs to be replenished, the amount of toner to be replenished Is increased by the predetermined replenishment consumption.
On the other hand, when it is determined that the toner replenishment operation number n is not less than 6 (No in S4), the process proceeds to step S31, and the control unit 1 sets the toner replenishment operation number n to 6 times. And the process proceeds to step S5. Thus, in the toner replenishment process, the toner replenishment operation frequency n is controlled to be 6 times the upper limit.

In step S5, the control unit 1 determines whether or not the remaining amount of toner in the developing device 42 detected by the remaining amount detection sensor 55 is less than a predetermined amount.
If it is determined in step S5 that the remaining amount of toner is not less than a predetermined amount (No in S5), the process proceeds to step S51, where the remaining amount of toner is greater than or equal to the predetermined amount. The control unit 1 starts measuring the time (hereinafter referred to as “satisfaction time”) in which a certain state (hereinafter referred to as “satisfaction state”) continues. Here, the control unit 1 when executing the time measuring process corresponds to the state time measuring means.
In the following step S52, it is determined whether or not the toner remaining amount detected by the remaining amount detection sensor 55 is in the sufficient state where the remaining amount of the toner is equal to or greater than the predetermined amount, that is, whether or not the sufficient state is continued. The processing is repeatedly executed until it is determined by the control unit 1 that the satisfaction time is 60 seconds or more in the next step S53. Here, if it is determined in step S53 that the sufficient time is 60 seconds or more (Yes in S53), it is determined that sufficient toner remains in the developing device 42, and the control unit 1 resets the number n of toner supply operations to 0 (S54), and the process proceeds to step S134. That is, even if the toner replenishment operation count n is 2 or more and the toner replenishment amount in step S9 described later is set to the second replenishment amount, the sufficient state is maintained for a predetermined time (here 60 seconds). In the case of the above, the toner replenishment operation count n is reset and the toner replenishment amount in step S9 to be described later is switched to the first replenishment amount. It is prevented that the toner is replenished and the toner overflows.
On the other hand, if it is determined in step S52 that the state is not the sufficient state (No in S52), the detection result of the remaining amount detection sensor 55 is in an unstable state where the detection result is fluid, that is, the toner in the developing device 42. Since there is a certain amount of toner that is not sufficient but can be said to be insufficient, there is no need to replenish the toner, so the process moves to step S134. In step S134, the cumulative amount of toner consumption calculated in step S1 and the average value of the printing rate are reset to 0, and the process returns to step S1. That is, when the shortage state is resolved, the normal initial state is restored.
As described above, while it is determined in step S5 that there is no shortage of toner in the developing device 42, the toner replenishing operation is not performed, and the number n of toner replenishing operations is changed according to the full time. After that, the process returns to step S1.

On the other hand, if it is determined in step S5 that the toner remaining in the developing device 42 has decreased and the remaining amount of toner detected by the remaining amount detection sensor 55 is less than a predetermined amount (Yes in S5), The process proceeds to step S6, and the control unit 1 starts measuring the time (hereinafter referred to as “insufficient time”) in which the state of less than the predetermined amount (hereinafter referred to as “insufficient state”) continues. Here, the control unit 1 when executing the time measuring process corresponds to the state time measuring means.
In the following step S7, it is determined whether or not the toner remaining amount detected by the remaining amount detection sensor 55 is in the shortage state where the remaining amount is less than the predetermined amount, that is, whether or not the shortage state is continued. Determined by part 1. The process of step S7 is repeatedly executed until the control unit 1 determines that the shortage time is 20 seconds or longer in the next step S8.
Here, before it is determined in step S8 that the shortage time is 20 seconds or more, if it is determined in step S7 that it is not currently in the shortage state (No side in S7), the remaining amount detection sensor 55 will be described. The detection result is fluid and unstable, that is, there is a certain amount of toner remaining in the developing device 42 that is not sufficient, but cannot be said to be insufficient. Since there is no need to replenish, the process proceeds to step S134.
On the other hand, if it is determined in step S8 that the shortage time is 20 seconds or longer (Yes in S8), it is determined that toner needs to be replenished, and the process proceeds to step S9.

In step S9, the replenishment roller 61 is controlled by the control unit 1 so that toner replenishment is performed n times. At this time, if the number n of toner replenishment operations is 1, as described above, the first replenishment amount of toner equivalent to the replenishment consumption amount is replenished to the developing device 42 (first replenishment amount). mode).
On the other hand, if the toner replenishment operation count n is increased to 2 or more in step S4 or S132 or S133 described later, the second replenishment amount larger than the replenishment consumption amount as described above. Toner is supplied to the developing device 42 (second supply mode). Here, when the first supply mode is executed, the control unit 1 sets the second supply amount in the first supply control means and the toner supply process, and executes the second supply mode. The control unit 1 is equivalent to a second supply control means.

When the toner is replenished in step S9, in step S10, time T1 and time T2 are set by the control unit 1 based on the average value of the printing rate calculated in step S1. The time T1 and the time T2 are times used as determination indexes in later-described step S12 and step S14, and are set according to the average value of the printing rate as shown in Table 1 below, for example. Specifically, when the average value of the printing rate is 6%, the time T1 is set to 100 seconds and the time T2 is set to 300 seconds.

  In step S11, it is determined by the control unit 1 whether or not the present shortage state is present, that is, whether or not the shortage state is continuing. In the next step S12, the shortage time is T1 seconds. It is repeatedly executed until it is determined by the control unit 1 as described above. Here, before it is determined in step S12 that the shortage time is equal to or longer than T1 seconds, if it is determined in step S11 that the shortage state is not currently present (No side in S11), it is sufficient in the developing device 42. Therefore, the process proceeds to step S111, and the controller 1 resets the toner replenishment operation count n to 0, and the process proceeds to step S134.

On the other hand, if it is determined that the shortage time has continued for T1 seconds or longer (Yes in S11), it is considered that the toner is not sufficiently left in the developing device 42 even after the toner supply in Step S9. Therefore, the process proceeds to step S13 in order to increase the toner supply amount.
In step S13, it is determined by the control unit 1 whether or not the present shortage state is present, that is, whether or not the shortage state is continuing. In the next step S14, the shortage time is T2 seconds or more. The process is repeatedly executed until it is determined by the control unit 1 to be present. If it is determined that the shortage time continues for T2 seconds or longer (Yes in S13), the process proceeds to the toner empty process in step S15.
In the toner empty process in step S15, the replenishment roller 61 is controlled by the controller 1, and toner replenishment from the toner container 43 to the developing device 42 is continuously executed for a predetermined time. Thereafter, when the result of detection of the remaining amount of toner by the remaining amount detection sensor 55 exceeds a predetermined amount before the predetermined time elapses, the process returns to step S1 via step S134. If the predetermined amount is not reached even after a predetermined time has elapsed, the operation display unit 2 displays that the toner is empty, and the toner supply process ends.

On the other hand, if it is determined in step S13 that the shortage time is not more than T2 seconds before it is determined in step S14 that the shortage state is not in the shortage state (No side of S13), the process proceeds to step S131.
In step S131, the control unit 1 determines whether or not a predetermined amount or more of toner remains in the toner container 43 based on the detection result of the remaining amount detection sensor 63. Here, when it is determined that a predetermined amount or more of toner remains in the toner container 43 (Yes in S131), it is possible to supply the predetermined supply amount by a single toner supply operation. Therefore, the process proceeds to step S132, and the control unit 1 sets the toner replenishment operation count n so that it is increased by 2 (n = n + 2).
However, if it is determined that the remaining amount of toner in the toner container 43 is less than the predetermined amount (No in S131), the replenishment amount by one toner replenishment operation is reduced and the amount corresponding to the predetermined replenishment consumption amount. Since it is considered that toner replenishment is not possible, the process proceeds to step S133, and the control unit 1 sets the number n of toner replenishment operations to increase four times (n = n + 4).
Thus, in the toner replenishment process, the toner replenishment operation frequency n is set based on the detection result of the remaining amount detection sensor 63. Specifically, when the amount of toner remaining in the toner container 43 is less than a predetermined amount (No side in S131), if the toner remains sufficiently in the toner container 43 (S131). The toner replenishment operation frequency n is set to be larger than (Yes side) (S133). Therefore, it is possible to prevent erroneous determination of toner empty due to a decrease in the toner replenishment amount per one time from the toner container 43 to the developing device 42 by reducing the remaining amount of toner in the toner container 43. be able to.

As described above, the printer X measures the time during which the shortage state or the full state continues, and according to the shortage time or the full time, the number of toner replenishments performed in step S9, that is, the toner supply The replenishment amount is adjusted. Specifically, as described above, the control unit 1 replenishes the first replenishment amount (supplementation of the number of toner replenishment operations once) or the second replenishment time according to the shortage time or the full time. The amount of replenishment (replenishment of toner replenishment operation twice or more) is switched. Here, the control unit 1 when executing such switching processing corresponds to control switching means.
As described above, in the printer X, not only the first replenishment amount of toner that is equal to or less than the consumption amount corresponding to the printing rate calculated based on the output image, but also the first replenishment amount. Since the toner supply of the second supply amount that is larger than the supply amount is performed as necessary, the toner in the developing device 42 is remarkably insufficient, and the process proceeds to the toner supply control by the conventional method (step S15). The frequency is reduced, and the overflow of the developer generated by the toner replenishment control according to the conventional method is prevented as much as possible.

Finally, specific progress examples of processing executed in the toner replenishment processing will be described for each case.
(1) When sufficient toner remains in the developing device 42.
When the cumulative amount of toner consumption calculated in step S1 is equal to or greater than the predetermined supply consumption (Yes side of S2), the toner supply whose initial value is 0 is passed through steps S3 and S4. The number of operations n is set to one. Here, since the toner remains sufficiently in the developing device 42, it is determined in the subsequent step S5 that the remaining amount of toner in the developing device 42 is equal to or greater than a predetermined amount, and in step S51. Timing of the full time is started. If it is determined in step S53 that the state determined to be in the satisfied state in step S52 has continued for 60 seconds or longer, the process proceeds to step S54, and the toner replenishment operation count n is reset to zero. Then, the process returns to step S1 via step S134. As a result, the image forming operation is repeatedly executed, and the toner gradually decreases.
(2) A case where toner remains in the developing device 42, but is not in a state sufficient to maintain the full state for 60 seconds or more.
Until step S52, the process proceeds in the same manner as in (1). However, since the amount of toner in the developing device 42 is smaller than that in (1), the satisfaction state is determined in step S52 due to uneven distribution or slight movement of toner. It may be judged that it is not. That is, the state is more unstable than (1). If it is determined that the condition is not satisfied, the process returns to step S1 without going through step S54. Accordingly, while this state continues, the toner replenishment operation number n is not reset, and therefore the toner replenishment operation number n is accumulated in step S4. Therefore, after that, the remaining amount of toner in the developing device 42 decreases, and it is determined that the remaining amount of toner is less than the predetermined amount in step S5 (Yes side of S5). If it is determined that the duration of the shortage state started in step S6 has elapsed for 20 seconds or longer (Yes in S7), the process proceeds to step S9 and toner supply is started. Here, the amount of toner replenished varies depending on the number n of toner replenishment operations. For example, when the state in which the steps S1, S2, S3, S4, S5, S6, S7, S134, and S1 are executed continues, the toner replenishment operation count n is gradually increased. The toner replenishment amount in S9 is larger than the predetermined replenishment consumption amount (second replenishment mode). However, as described above, when the toner replenishment operation number n becomes 6 or more at this time, the process proceeds to No in step S3, and the toner replenishment operation number n is set to 6. That is, the toner replenishment operation number n is accumulated up to 6 times.
Further, when the state shifts from the state (1) to the Yes side in Step S5, the toner replenishment operation count n is reset without being accumulated, so that the toner replenishment amount in Step S9 is the predetermined amount. It becomes an amount equivalent to the replenishment consumption amount (first replenishment mode).
As described above, when the toner is replenished in the developing device 42, after the times T1 and T2 are set in step S10, the processing branches depending on how long the shortage continues. Here, since the toner in the developing device 42 is not in a very shortage state, it is considered that the shortage state is resolved in less than the time T1 after the replenishment of toner (No side of S11). In this case, the process returns to step S1 after the toner replenishment operation count n is reset via step S111. That is, since the toner full state has been reached, the state is the same as the process (1), and the number n of toner replenishment operations is reset as in step S54.
(3) The toner in the developing device 42 is extremely short.
In this case, the process proceeds up to step S12 as in (2), but since the duration of the shortage continues for the time T1 or more, the process proceeds from step S12 to step S13. Here, if the shortage state is such that the shortage state is eliminated within the time T2, the process proceeds to step S131, and the toner replenishing operation is performed according to the remaining amount of toner in the toner container 43. After the number of times n is increased and set, the process returns to step S1 via step S134. Accordingly, in this state, the amount of replenishment when toner is replenished in step S9 increases, so that the shortage of toner in the developing device 42 can be resolved. If the shortage state continues even after the time T2 has elapsed, the process proceeds to step S15 and the toner empty process is executed.

1 is a block diagram showing a schematic configuration of a printer according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing a peripheral configuration of a developing device provided in the printer according to the embodiment of the present invention. FIG. 3 is a schematic view of the inside of the developing device provided in the printer according to the embodiment of the present invention as viewed from above. 6 is a flowchart for explaining an example of a procedure of toner supply processing executed in the printer according to the embodiment of the invention.

Explanation of symbols

X: Printer (an example of an image forming apparatus)
Y ... Information processing device 1 ... Control unit 2 ... Operation display unit 3 ... Storage unit 4 ... Image forming unit 5 ... Communication processing unit 10 ... LAN
41... Photoconductor drum 42... Developing device (an example of developing means)
43. Toner container (an example of a developer reservoir)
51: Developing roller 52 ... Toner replenishment port 53, 54 ... Conveying roller 55 ... Remaining amount detecting sensor (an example of first remaining amount detecting means)
61 ... Supply roller (an example of developer supply means)
62 ... Stirring roller 63 ... Remaining amount detection sensor (an example of second remaining amount detecting means)
S1, S2,... Processing procedure (step) number

Claims (3)

Developing means for developing an electrostatic latent image formed on a predetermined image carrier with a developer, first remaining amount detecting means for detecting the remaining amount of the developer in the developing means, and storing the developer Developer replenishing means for replenishing the developer to the developing means from the developer storage section, developer consumption calculating means for calculating the amount of developer consumed by the developing means based on the print rate of the output image; , An image forming apparatus comprising:
A state timing unit that counts a time during which a state where the detection result by the first remaining amount detection unit is less than a predetermined amount continues and / or a time during which the state equal to or greater than the predetermined amount continues;
First replenishment that causes the developer to replenish a first replenishment amount that is equal to or less than the developer consumption calculated by the developer consumption amount calculating unit with respect to the developer replenishing unit. Control means;
A second replenishment amount that is larger than the first replenishment amount is set based on the time measured by the state timing unit, and the developer replenishment unit is made to replenish the second replenishment amount to the developing unit. Second supply control means;
Control switching means for switching between the first replenishment control means and the second replenishment control means in accordance with the time measured by the state timing means;
An image forming apparatus comprising: A second remaining amount detecting means for detecting the remaining amount of the developer in the developer storing section;
2. The image formation according to claim 1, wherein the second supply control unit sets the second supply amount based on a time measured by the state timing unit and a detection result by the second remaining amount detection unit. apparatus.   When the time for which the state where the detection result by the first remaining amount detecting means timed by the state time measuring means is a predetermined amount or more continues for a predetermined time or longer is the control switching means, The image forming apparatus according to claim 1, wherein the image forming apparatus is switched from a replenishment control unit to the first replenishment control unit.

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