JPH0233156B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to a copying machine that requires filling with replenishment developer and has a warning means for instructing the filling of the replenishment developer.

BACKGROUND OF THE INVENTION The mainstream of copying machines currently in practical use is an electrophotographic copying machine. In these copying machines, a developer consisting of a mixture of toner and carrier is used to develop the electrostatic latent image. Replenishment developer, specifically replenishment toner, is automatically and sequentially replenished for the subsequent developer. By the way, in these copying machines, when the replenishment developer filled inside the machine is used up, the toner concentration in the developer decreases as the electrostatic latent image develops, and as a result, the image density decreases. This will have an adverse effect on the copied image, including a decrease in the quality. For this reason, these copiers issue a warning instructing the operator to refill replenishment developer when the replenishment developer filled inside the machine is used up. Generally, they have the means to do so.

The most common warning means is a warning lamp provided on the operation panel of the copying machine, and the alarm lamp is installed on the operation panel of the copying machine. Turns on only when the amount of replenishment developer remaining in the tank is small.
It's starting to look like it's being done. The relationship between changes in the toner concentration in the developer and the timing of turning on the warning lamp in an electrophotographic copying machine having such a warning means will be explained with reference to FIG. 1 as follows.

In FIG. 1, the vertical axis represents the toner concentration in the developer, the horizontal axis represents the number of copies made by the electrophotographic copying machine, and the solid line A represents the relationship between the two. First of all,
Until the replenishment developer is completely consumed,
That is, the toner concentration in the developer is maintained at a predetermined value of to until the point _p2 in FIG. 1 is reached. Then, it gradually decreases after being completely consumed. Here, the warning lamp is normally turned on before the supplied developer is completely consumed, so the time when the warning lamp is turned on is the first.
In the figure, p is represented by _one point.

As is clear from Figure 1, even though the warning lamp is turned on, the toner concentration in the developer does not _immediately decrease;
-a) copies can be made as usual; In addition, even after the replenishment developer is completely consumed, the toner concentration in the developer does not drop suddenly, and the _P4 point, that is, the value of t ₂ where the toner concentration value is below a certain tolerance. (d-
b) It is possible to make copies of multiple sheets with an image quality that is acceptable for practical use. Of course, the image quality gradually deteriorates as the toner density value deviates from the desired value of to. In a normal desktop electrophotographic copying machine, the above (d-a) value is 800 to 1000 in _A4 size.
That's about it.

For this reason, the operator must ensure that the warning lamp is turned on.
It is common practice to start the copying operation and obtain a copy without immediately filling the replenishing developer with the developer. By the way, since copiers installed in general offices are operated by many people all the time, if the warning lamp is already on,
An operator who is about to start a copying operation cannot know when the warning lamp is turned on and how much copying has been performed since then. For this reason, as a result of a large number of copies being made after the warning lamp is turned on, the toner concentration in the developer drops significantly from the to value, and even though copies with good image quality cannot be obtained, The copy operation starts without knowing the
Occasionally, problems occurred when a large number of copies with poor image quality were created.

Such a problem can also be caused by an operator who uses the copying machine later unless the operator fills the copying machine with replenishing developer at this point.

OBJECT OF THE INVENTION An object of the present invention is to provide a copying machine that can prevent the occurrence of the above-mentioned problems. That is, it is an object of the present invention to provide a copying machine that can prevent the production of copies with poor image quality as described above.

A further object of the present invention is to provide a copying machine that can accurately and accurately provide information to an operator attempting to make a copy as to whether or not a good copy image can be obtained.

SUMMARY OF THE INVENTION The present invention is a copying machine that performs dual developer shortage warnings, and includes a copy paper loading section that allows copy paper of different sizes to be loaded, and a copy paper loading section that allows loading of copy paper of different sizes. a copy paper size detection mechanism for detecting the size; a developing device for accommodating the developer to form a developed image of the developer on the copy paper; and a remaining amount for detecting the remaining amount of the developer. a detection means; a first warning prompting developer filling; a warning means for issuing a second warning different from the first warning; a first control means for controlling the warning means to issue the first warning when detecting that the copy paper size detection mechanism storage means for storing the permissible number of copies obtained by multiplying the area value corresponding to the size of the copy paper detected by a predetermined value; a counting means for counting the number of sheets; after the first warning is issued, a predetermined value is set to an area value corresponding to the size of the copy paper detected by the copy paper size detection mechanism; calculating the number of consumed copies obtained by multiplying the number of copies counted by the means, and subtracting the consumed number of copies from the allowable number of copies stored in the storage unit to set the remaining number of copies; and second control means for controlling the warning means to prohibit the first warning and issue the second warning when determining that the number of remaining copies has become 0 or less. , If the copy paper size detection mechanism detects that the copy paper size has been changed after the first warning is issued and before the second warning is issued, the copy paper size is changed. By providing a changing means for changing the number of remaining copies, which was set in the calculation means before detecting that the size of the copy paper has been changed, in accordance with the changed size of the copy paper, In order to prevent the creation of defective copies, the information regarding whether or not a good copy image can be obtained is provided accurately and accurately to the operator attempting to make copies. The main points are as follows.

Embodiment As an embodiment of the copying machine according to the present invention, the second to
The powder image transfer type electrophotographic copying machine will be explained with reference to FIG. Note that the copying machine according to the present invention is not limited to these types as long as it requires replenishment of developer.

First, the structure of the developing device in the above embodiment will be explained as follows with reference to FIG. In FIG. 2, the developing device De is installed facing the circumferential surface of the electrophotographic photosensitive drum 1 which is rotationally driven in the direction of arrow d, and is equipped with a copy image previously formed on the circumferential surface of the photosensitive drum 1. The electrostatic latent image corresponding to the image is developed and visualized. This developing device De is roughly divided into two parts: a developing section and a developer replenishing section, and a developing sleeve 3, a magnetic roller 4, and a bucket troller 5 are each rotatably mounted in a developing tank 2 in the developing section. The developing sleeve 3 and the magnetic roller 4 are driven to rotate in the direction of the arrow e when developing the electrostatic latent image, and transport the magnetic brush made of the developer 6 formed on the circumferential surface of the developing sleeve 3 in the opposite direction of the arrow e. The circumferential surface of the photosensitive drum 1 is rubbed with a magnetic brush. Also, bucket troller 5
is adapted to supply the developer 6 contained in the developer tank 2 onto the circumferential surface of the developing sleeve 3 by being rotationally driven in the direction of arrow f. The developer 6 is a so-called two-component magnetic developer made of a mixture of a small-diameter magnetic carrier and an insulating toner.

On the other hand, in the developer replenishment section, a replenishment developer 6' is stored in a replenishment developer storage tank 7.
This replenishment developer 6' is supplied to the developer 6 contained in the developer tank 2 by a replenishment roller 8 which is rotationally driven in the direction of arrow g at appropriate times. Therefore, the toner concentration in the developer 6 contained in the developer tank 2 is maintained at the value to. Further, a replenishment developer stirring rod 9 swinging in the direction of arrow h is provided in the tank 7 to prevent crosslinking of the replenishment developer 6' within the tank 7. Furthermore, a remaining amount detecting element 10 is attached to the side wall of the tank 7 for detecting the remaining amount of the replenishing developer 6'. This remaining amount detection element 10 has a diaphragm that vibrates in the direction of arrow i on the right end surface in the figure, that is, the surface facing the replenishment developer 6' in the tank 7, and the amplitude of the diaphragm changes depending on the magnitude of the amplitude of the diaphragm. Therefore, the remaining amount of replenishing developer 6' is detected. Specifically, when the top surface of the replenishment developer 6' stored in the tank 7 becomes below the dashed line B in the figure, a toner empty display provided in the operation panel 11 (to be described later) is displayed. Turn on the warning lamp in frame 14
let Details regarding this specific control will be described later with reference to the flowchart shown in FIG. Note that the replenishment developer 6' consists only of replenishment toner having the same composition as the toner mixed in the developer 6.

Next, with reference to FIG. 3, the flow related to the control of replenishment developer filling instructions in the above embodiment using a microcomputer will be explained item by item as follows. In the flow described below, the upper surface of the replenishment developer 6' stored in the replenishment developer storage tank 7 is indicated by the dashed-dotted line B.
The warning lamp will turn on when the following occurs, and then
When 600 A4 size sheets have been copied, the warning lamp flashes, and when 200 more sheets have been copied, the next copying operation is prohibited. The flow related to the control of replenishment developer filling instructions in the copying machine of the present invention is not limited to such a flow.

(a) When the top surface of the replenishment developer 6' stored in the replenishment developer storage tank 7 is above the dashed-dotted line B; When the power is turned on, various processes related to the copying operation are performed in the step. The processing related to this copying operation includes turning on and off each image forming element after the print button 17 provided in the operation panel 11 is pressed. Then, following the step, it is determined in a step whether or not copying of one sheet has been completed. Here, if it is determined that copying of one sheet has been completed, the copy completion flag is set in step
When Fc is set to "1", the program then moves to the step. On the other hand, if the completion of the copying is not determined, the flag
Fc is not set and moves directly from step to step. Specifically, the above-described determination is made based on whether or not the copy paper is discharged outside the machine, and in the embodiment described above, a copy paper conveyance path near the copy paper ejection port is provided for this purpose. A paper passage detection mechanism is used. By the way, in the step, the presence or absence of the replenishment developer 6' in the replenishment developer storage tank 7, specifically, the remaining amount detection element 10 detects the upper surface of the replenishment developer 6' stored in the tank 7. It is determined whether or not the dashed line B is above the dashed line B.
In the case of (a) above, it is determined that replenishment developer 6' is present,
Move on to the next step. Then, in step it is determined whether the toner empty flag Fc has already been set. Setting of the toner embodiment flag Fc is done in the steps described below.
In case (a), the flag Fc has not been set yet, and the process moves from step to step. As a result, the copy completion flag is set in the step.
Fc is reset, and then various processes other than those related to the copying operation in the copying machine are performed in the step, and the process returns to the step again. The processing includes turning on and off the heat source of the heat fixing device. Note that the flow between steps ~ and ~ is also common to cases (b) to (e) described later, so the explanation thereof will be omitted in cases (b) to (e) described later.

(b) When the top surface of the replenishment developer 6' stored in the replenishment developer storage tank 7 is below the dashed dot line B; this point is represented by point P ₁ in Figure 1, and this point Thereafter, everything is transferred from step to step. Then, in step it is determined whether the warning flag Fw has already been set. The warning flag Fw is set in the step described below.
In the case (b) above, the warning flag Fw has not yet been set, and the process is shifted from step to step. Also, in this step, it is determined whether the toner empty flag Fc has already been set. By the way, the flag Fe is set in the step described below, but in the case of (b), the flag Fe is not set yet, and the process moves from step to step through steps ~. be done. In the above step, the warning lamp in the toner empty display frame 14 provided in the copying machine operation panel 11 is turned on.
is turned on to prompt the operator to fill the replenishment developer storage tank 7 with the replenishment developer 6', and at the same time, in the step, the flag Fe is set to "1", and furthermore, in the step, the counter is A predetermined allowable number of copies is set. Here, the allowable number of copies set on the counter differs depending on the size of copy paper loaded in the copying machine. For example, if A4 size copy paper is loaded, The copy paper size detection mechanism installed in the copy paper size detection mechanism detects this and sets the number of copies to 600. Incidentally, in the case of A3 size, B4 size, and B5 size, it is 300, 400, and 800, respectively.
The number of sheets is set. Note that the number of these sheets is inversely proportional to the area ratio of each size, and when all the above numbers are copied, the total copy area is equal to each other. On the other hand, following the above steps,
In the step, it is determined whether the contents of the counter have been decremented to "0" or not, but since the number of sheets has just been set in the step, the process moves from step to step and repeats the next cycle. Therefore, it is returned to the step via the step.

From the next cycle onwards, since the toner empty flag Fe has already been set to "1", the process moves from step 1 to step 2 through steps 〓〓 to 〓〓.
Steps 〓〓 to 〓〓 are steps for changing the contents of the counter in accordance with the change in the size of the copy paper, and decrementing the contents of the counter by "1" when one sheet of copying is completed. Specifically, in step <<>, it is determined whether or not the size of the copy paper has been changed. Here, if a change in the size of the copy paper is not determined, the contents of the counter are not changed and the process directly moves from step <<> to step <<>. On the other hand, if the detection mechanism detects a change in the size of the copy paper, and as a result it is determined that the size of the copy paper has been changed, the content of the counter is changed based on the following formula in step, After that, move on to step 〓〓.

Contents of the counter after change=Contents of counter before change・S/S' However, if the contents of the counter after change are decimals, the decimal part is rounded down and only the integer part is set in the counter.

S...Area value corresponding to the size of the copy paper before the change S'...Area value corresponding to the size of the copy paper after the change The above area value is stored in advance in the RAM of the microcomputer. ,
A4A5, B4, B5, B6... are 16, 8, 4, respectively.
Corresponding values are 12, 6, 3, etc. Further, in step <<>, it is determined whether the copy completion flag Fc has already been set, that is, whether one copy has already been completed. And 1
If it is determined that copying of the first sheet has been completed, the content of the counter is decremented by 1 in step 〓〓, and the process moves to step 〓〓, whereas if it is not determined that copying is complete, step 〓〓 is Go directly to the step without going through the process. Here, after the permissible number of copies is set as described above in the step, the content of the counter is "0" until the copying of 600 A4 size sheets is completed.
Until then, the process moves directly from step to step, repeating the same flow each time.

(c) After the warning lamp is turned on, print it to A4 size.
When 600 copies have been made; this point is represented by ₃ points in Figure 1, and the toner concentration in the developer has reached a certain tolerance value _t2 or higher.
Although the value of t ₁ is such that copying can be performed with an image quality that is acceptable for practical use, the image is in a state of gradual deterioration as copying continues. At this point, it is determined in step that the contents of the counter have become "0", and the process moves from step to step. Then, in the step, the warning lamp that has already been turned on is turned on and off, to further urge the operator to fill the replenishment developer storage tank 7 with the replenishment developer 6' in a manner different from the case (b) above. At the same time, it makes people realize that it is difficult to obtain good copies.
And furthermore, a warning flag is set in the step.
At the same time as Fw is set to "1", the limit number of copies is set for the counter in step. The limit number of copies set here is 1/3 of the above-mentioned allowable number of copies, and if _A4 size copy paper is loaded, 200 copies are set. The specific method for setting the number of sheets is substantially the same as the method for setting the number of sheets in the step described above. On the other hand, following the above step, it is determined in the step whether the contents of the counter have been decremented to "0", but since this is immediately after the number of sheets has been set in the step, there is a transition from step to step. It is then returned through the steps to repeat the next cycle.

From the next cycle onward, since the warning flag Fw has already been set to "1", the process moves from step to step . These steps correspond to the steps 〓〓〓 to 〓〓, respectively, and are the same, so the explanation thereof will be omitted.
Note that after the limit number of copies is set as described above in the step, the content of the counter will not become "0" until the copying of 200 A4 size sheets is completed; You move directly from step to step, repeating the same flow each time.

(d) After the warning lamp flashes, 200 copies of A4 size paper are made; This point is represented by point P ₄ in Figure 1, and the image quality is no longer suitable for practical use. Copying can only be done in this way. At this point, it is determined in step that the contents of the counter have become "0", and the process moves from step to step. Then, in step, the start of the next copying operation is prohibited. That is, even if the print button 17 is pressed, the copying operation will not be started.

The specific process for prohibiting the start of the copying operation is to set a copy prohibition flag in the step described above, and when this flag is set, to prohibit the start of the copying operation, each image forming element after the print button 17 is pressed in the step. on-off
It is also possible to perform processing that jumps over control-related flows. In this case, it is only necessary to reset the copy prohibition flag in step 〓〓, which will be described later, and it is more efficient to skip over the flow related to steps 〓〓〓 when the copy flag is set. It is true.

(E) When the replenishment developer 6' is filled into the replenishment developer storage tank 7 after the start of the copying operation is prohibited, or when it is filled after the warning lamp is turned on; The replenishment developer 6' is filled. When this happens, the remaining amount detecting element 10 detects this, and the process moves from step to step. At this point, it is determined whether or not the toner empty flag Fe has already been set, but since the flag Fe was set to "1" in the step before the replenishment developer 6' was filled. From the step, the process goes through steps 〓〓〓 to 〓〓. In the step 〓〓, the warning lamp is turned off, and in the step 〓〓, the flag Fe and the warning flag Fw are turned off.
is reset, and furthermore, in step 〓〓, if copy prohibition processing has been performed by the step, it is canceled. Then, from step to step, back to step,
In the next cycle, the same flow as in case (a) above will be repeated.

The above is an explanation of the flow related to the control of the replenishment developer filling instruction in the embodiment. In addition, in the above flow, if the power of the copying machine is turned off,
The contents of the counter and the status of each flag are saved in a memory backed up by a battery. Next, referring to FIG. 4, the structure of the operation panel in the above embodiment will be explained as follows. In Figure 4, operation panel 1
1, a plurality of display frames 12 to 15 including a toner empty display frame 14, and a digital display number display lamp 16 are provided. Further, on the left side of the print button 17 in the operation panel 11, a check button 18 and a continuous copy number setting button 19 are provided. The number display lamp 16 normally displays the set number of continuous copies, but in the embodiment, when the check button 18 is turned on, the toner empty flag Fe or warning flag Fw is turned on. Only when the counter has already been set, the contents of the counter are displayed, and the operator is informed of the number of copies remaining within the allowable number of copies or the number of copies remaining according to the size of the copy paper. It's starting to look like this. Therefore, after the warning lamp is turned on, the operator can know in detail to what extent copies can be made with good image quality from the remaining number of allowed copies by turning on the check button 18. This is the translation. By the way, check button 1
Even if you do not turn on 8, you can tell from the lighting status of the warning lamp whether good copying is possible or not.
This makes it possible to prevent the creation of copies with poor image quality.

The above is an explanation of the embodiment of the copying machine according to the present invention, but this embodiment can be modified in various ways. For example, regarding the remaining amount detection means for detecting the remaining amount of replenishment developer, instead of directly detecting the remaining amount of replenishment developer 6' in the replenishment developer storage tank 7,
Conversely, it may be detected that the replenishment developer 6' is completely consumed and the remaining amount is zero based on a decrease in the toner concentration in the developer in the developer tank 2. Furthermore, regarding the changing means for changing the mode of replenishment developer filling instruction by the warning means, instead of changing the warning lamp from a constantly lit state to a blinking state, warning lamps of different colors are sequentially turned on. The color tone may be changed. in particular,
As the amount of copies stored in the storage means increases, the color tone of the warning lamp may be changed from green to yellow, or further from yellow to red. Alternatively, the blinking interval of the warning lamp may be gradually shortened as the amount of copies stored in the storage means increases. In the above embodiment, in order to display the remaining number of allowed copies or limited number of copies, the storage means stores the copy amount in the form of subtraction, but it is not possible to add the number of copies. In addition, it is not necessary to store the copy amount in two stages such as the permissible number of copies and the limit number of copies.

Effects of the Invention In the copying machine according to the present invention, if the size of copy paper to be used is changed after the first warning regarding developer shortage is issued, a second warning is issued in response. Since it has a changing means for changing the number of remaining copies that can be made, information on whether or not a good copy image can be obtained is provided accurately and accurately to the operator attempting to make a copy. can do. Furthermore, as a result, it is possible to prevent the creation of copies with poor image quality.

[Brief explanation of drawings]

FIG. 1 is a diagram schematically showing the relationship between the toner concentration in the developer and the number of copies after an instruction is given to add replenishment toner in an electrophotographic copying machine, and FIG. Drawings showing the structure of the developing device in the embodiment of the copying machine, FIG. 3 is a flowchart regarding control of replenishment developer filling instructions in the embodiment, and FIG. 4 shows the main structure of the operation panel in the embodiment. FIG. De...Developing device, 6...Developer, 6'...Replenishment developer, 10...Remaining amount detection element, 11...Operation panel, 14...Toner empty display frame.

Claims (1)

[Scope of Claims] 1. A copy paper loading section that allows copy paper of different sizes to be loaded; a copy paper size detection mechanism for detecting the size of the copy paper loaded in the copy paper loading section; a developing device for accommodating the developer to form a developed image of the developer; a remaining amount detection means for detecting the remaining amount of the developer; a first warning prompting the filling of the developer; , a warning means for issuing a second warning in a manner different from the first warning, and when the warning means detects that the remaining amount of developer has become less than a certain value, the warning means issues the first warning. a first control means for controlling the warning means to issue a warning; and an area value corresponding to the size of copy paper detected by the copy paper size detection mechanism when the first warning is issued. a storage means for storing the permissible number of copies obtained by multiplying by a predetermined value; a counting means for counting the number of copies made after the first warning is issued; After the warning is issued, the area value corresponding to the size of the copy paper detected by the copy paper size detection mechanism is multiplied by a predetermined value and the number of copies counted by the counting means. calculation means for calculating the number of copies consumed and subtracting the number of copies consumed from the number of allowable copies stored in the storage unit to set the number of remaining copies; and a second control means for controlling the warning means to prohibit the first warning and issue the second warning after the first warning is issued. and before the second warning is issued, when the copy paper size detection mechanism detects that the size of the copy paper has been changed, before the change in the size of the copy paper is detected. A copying machine characterized by comprising: a changing means for changing the number of remaining copies set in the calculating means in accordance with the changed size of the copy paper.