JP2780347B2 - Image forming device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus that forms a hard copy image using an electrophotographic process.

[Conventional technology]

2. Description of the Related Art Conventionally, an electrophotographic process has been widely used as a technique for forming a hard copy image in an image forming apparatus such as a copying machine, a facsimile, an optical printer using a laser beam, an LED array, or the like.

The electrophotographic process includes a charging process for uniformly charging the surface of a photoreceptor, an exposure process for exposing the surface of the photoreceptor in accordance with image information to partially remove a charge, thereby forming a latent image, The method includes a developing process of forming a toner image by attaching toner to a developer in an image, a transfer process of transferring the toner image to a recording sheet, and a fixing process of fixing the toner image transferred to the recording sheet.

In an image forming apparatus using an electrophotographic process, in order to obtain a hard copy image of an appropriate (ie, standard) image quality, physical properties (surface potential of a photoconductor, exposure amount, toner Density, etc.), and the operation of each mechanism is defined according to the physical property value.

However, in general, a specific physical property value gradually deviates from a predetermined value due to the frequency of use and the environment (temperature, humidity, vibration, etc.) of the installation location. That is, the image quality of the hard copy image gradually changes due to adhesion of impurities to the photoconductor, deterioration of the exposure lamp, contamination of the mirror of the optical system, aging of the circuit constant of the control circuit, and the like. It should be noted that sudden changes in image quality may occur.

For this reason, conventionally, in the image forming apparatus, for example, when the power is turned on, the set values of the respective units are automatically set so that the image formation is performed under the conditions approximating the standard electrophotographic process conditions by compensating for the variation in the physical property values. (Image adjustment).

By the way, the operation states related to the quality of the image quality of the image forming apparatus after the power is turned on are roughly classified into an image formation possible state in which image formation is possible, and an image formation impossible state in which image formation is impossible due to occurrence of a trouble (trouble). There is a state.

In the image-capable state, in the above-described image adjustment, a proper state in which the operation setting of a predetermined standard value is performed, and a standard value in a predetermined mechanism corresponding to a change in a physical property value. There is an improper state in which operation settings of different values are performed. In the case of an improper state, performance degradation often occurs in at least some of the mechanical units. In addition,
Even if it is temporarily in an inappropriate state, it may return to an appropriate state due to environmental changes such as temperature.

Troubles in an image-impossible state include shortage of consumables such as recording paper and toner or paper jam (jam).
There are minor troubles that can be dealt with by the operator as described above, and serious troubles that need to be repaired by a serviceman such as failure or damage of each part. When a minor trouble occurs, image formation can be resumed by replenishing consumables or removing jammed paper. However, when a serious trouble occurs, that is, when the operation state of the image forming apparatus is abnormal, it is impossible to form an image until measures such as component replacement are performed.

Generally, in an image forming apparatus, an operation state is identified (self-diagnosis) based on an output of a sensor provided at an appropriate position inside the apparatus, and when some trouble occurs, that is, when an image cannot be formed. Displays the trouble content and the location where the trouble occurred. This allows
The operator can take necessary actions such as contacting a service person.

On the other hand, the serviceman operates the image forming apparatus, for example, at the time of a periodic inspection, checks the image quality by looking at the hard copy image formed at that time, and performs cleaning to make the operating state appropriate if necessary. Maintenance work such as changing parts, changing set values for each mechanism by operating a DIP switch, and the like.

[Problems to be solved by the invention]

In the conventional image forming apparatus, the serviceman cannot know the operation state (condition) regarding the quality of the image quality before the inspection. That is, even if there is a difference between the image quality at the time of inspection and the appropriate image quality, it is not possible to know whether the difference has occurred suddenly or gradually, so that the cause of the image quality change (defective part) is determined. However, there is a problem that it is difficult to perform an appropriate treatment.

For this reason, when a symptomatic treatment for obtaining a hard copy image of an appropriate image quality is performed for the time being, there is a possibility that the deterioration of each part is accelerated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide an image forming apparatus capable of determining a cause of a change in image quality of a formed hard copy image and performing an appropriate measure for obtaining an appropriate image quality. I have.

Another object of the present invention is to provide an image forming apparatus capable of detecting an operation state at a location distant from an installation location and speeding up maintenance work.

[Means for solving the problem]

In order to solve the above-mentioned problem, according to the present invention, in an image forming apparatus for forming a hard copy image using an electrophotographic process, a sensor means for measuring a physical property value accompanying the electrophotographic process, and the sensor The output of the means is compared with a first threshold to determine an inoperable state and an operable state of the image forming apparatus, and in the operable state, the output is compared with a second threshold to determine the image forming apparatus. Self-diagnosis means for determining whether the operation state regarding the quality of the image quality is an appropriate state or an inappropriate state, and storage means for storing management information indicating the contents of the inappropriate state. Is configured as

The invention according to claim 2 is characterized in that, in addition to the above-described configuration, a display unit for displaying each of the management information is provided.

The third aspect of the present invention provides the configuration of the first aspect of the present invention,
A communication unit for transmitting the management information to an external management device that manages the operation state of the image forming apparatus is provided.

(Operation)

Physical property values associated with the electrophotographic process are measured by the sensor means.

The self-diagnosis unit compares the output of the sensor unit with a first threshold to determine an inoperable state and an operable state of the image forming apparatus, and in the operable state, compares the output with a second threshold. In comparison, it is determined whether the operation state of the image forming apparatus regarding the quality of the image quality is an appropriate state or an inappropriate state.

The storage unit stores management information indicating the contents of the inappropriate state.

 The display means displays each management information.

The communication unit transmits each piece of management information to an external management device that manages the operation state of the image forming apparatus.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

 FIG. 1 is a front sectional view showing a main part of the copying machine A.

In FIG. 1, a photosensitive drum 5 is rotatably arranged in a direction of an arrow Ma at a constant peripheral speed v. Around the photosensitive drum 5, a charging charger 6, an inter-image eraser 10, and a developing device 7 for an electrophotographic process. , Transfer charger 28, separation charger
29, a cleaning device 9 and a main eraser 8 are provided. A surface voltmeter 90 for measuring the surface potential of the photosensitive drum 5 is provided between the exposure position X2 and the inter-image eraser 10, and a reference voltage is provided between the separation charger 29 and the cleaning device 9. In order to measure the density of the toner image, a reflection type photo sensor 19 including a light emitting element 19a and a light receiving element 19b is provided.

The surface of the photosensitive drum 5 is uniformly charged by passing through the charging charger 6, and the optical system 20 is exposed at the exposure position X2.
Exposure. The surface charge of the photosensitive drum 5 is partially removed by the exposure, and the original D
Is formed. Surface charges other than the latent image are erased by the inter-image eraser 10.

The optical system 20 includes an exposure lamp 21 for irradiating a document D placed on the document table glass 1, mirrors 22a to 22d for guiding reflected light B from the document D to an exposure position X2, and a projection lens 23. Have been. At the time of exposure scanning of the document D, the exposure lamp 21 and the mirror 22a move at a speed v / m (m
Move at a copy magnification), and the mirrors 22b and 22c can move at a speed v / 2m.

The latent image formed on the surface of the photosensitive drum 5 is visualized as a toner image developed by the developing device 7.

The developing device 7 uses a developer consisting of a mixture of a magnetic carrier and an insulating toner, and attaches the toner to a latent image (charge existing portion, that is, a non-exposed portion) passing through the developing position X3 by a known magnetic brush method. , So-called forward rotation development. Inside the developing tank 70, a developing sleeve 71 having a built-in magnetic roller 72, an ear height regulating plate 73, a bucket roller 74,
A screw roller 75 is provided, and a toner density sensor 80 is disposed below the screw roller 75.

When the bucket roller 74 rotates in the direction of arrow Mc, the developer is attracted to the outer peripheral surface of the developing sleeve 71 by the magnetic force of the magnetic roller 72, and is transported to the developing position X3 based on the rotation of the developing sleeve 71 in the direction of arrow Md. Is done. The toner concentration sensor 80 is for measuring the weight ratio T / C [wt%] of the toner to the entire developer from the magnetic permeability of the developer.

A toner tank 76 is provided at an upper portion of the developing tank 70, and a toner supply roller 77 is provided at a bottom portion thereof. When the toner supply roller 77 is driven to rotate by the supply motor 78, toner is supplied from the toner tank 76 to the screw roller 75. The replenished toner is supplied to the screw roller 75
The developer is stirred and mixed with the developer already existing inside the developing tank 70 by the rotation of the developer tank 70 and is sent to the bucket roller 74. The frictional charging occurs due to the stirring and mixing here, and the magnetic carrier and the toner are charged with polarities different from each other. The negative toner adheres to the surface of the photosensitive drum 5 by electrostatic attraction with the surface charge of the photosensitive drum 5 at the developing position X3. At this time, a developing bias VB of a predetermined voltage is applied to the developing sleeve 71 in order to prevent toner from adhering due to residual charges on the surface of the photosensitive drum 5 (charges remaining on exposed portions).

On the other hand, the paper P is conveyed by the timing roller 30 while keeping timing with the rotation of the photosensitive drum 5, and the transfer position is changed.
At X4, the sheet P toner image is transferred onto the sheet P by the transfer charger 28. The sheet P to which the toner image has been transferred is separated from the photosensitive drum 5 by the separation charger 29 and sent to a fixing device (not shown).

Thereafter, the remaining toner is removed from the surface of the photosensitive drum 5 by the cleaning device 9 and the remaining charge is removed by the main eraser 8 to prepare for the next exposure.

 FIG. 2 is an enlarged view of a part of the optical system 20.

The slider unit 24 supporting the exposure lamp 21 and the mirror 22a is provided so as to be reciprocally movable below the platen glass 1 to expose and scan the original D during the copying operation as described above. At the time of adjustment, it is placed at the adjustment position Y1 or Y2.

The adjustment position Y is provided on the lower surface of the upper cover 26 of the copying machine A.
Adjustment seals 25a and 25b are attached so as to correspond to 1, Y2. The adjustment sticker 25a has a reflectance equivalent to the background (white background) of a normal manuscript paper.
25b has a reflectance equivalent to a gray background (halftone image).

FIG. 3 is a diagram showing the configuration of the charger 6 and the output circuit 202.

The charging charger 6 includes a charge wire 61, a stabilizer 64,
This is a scorotron charger configured with a mesh grid 63.

A constant high voltage is supplied to the charge wire 61 from a high voltage transformer 62 that is turned on and off by a first CPU 201 described later. The grid 63 is installed via varistors 65a to i connected in series in the output circuit 202.
To h can be short-circuited by short-circuit switches SW1 to SW8. By turning on / off each of the short-circuit switches SW1 to SW8 by a control signal from the first CPU 201, the potential of the grid 63 is controlled. Thus, the amount of charge traveling from the charge wire 61 to the surface of the photosensitive drum 5 is controlled, and the surface potential of the photosensitive drum 5 is set.

FIG. 4 is a view showing a set level of the charger 6. In this embodiment, the rated voltage of the varistors 65a to 65h is set to 15 volts, the rated voltage of the varistor 65i is set to 790 volts,
The surface potential of the photosensitive drum 5 can be set in nine levels from 1 to 9 at a pitch of 15 volts around the standard level 5. For example, at level 5, control is performed to turn on the short-circuit switches SW1 to SW4 so that the surface potential of the photosensitive drum 5 becomes 650 volts. Note that the rated voltages of the varistors 65a to 65h may be different from each other to increase the number of levels.

In the following description, the set level of the charger 6 is referred to as “HV level”.

FIG. 5 is a block diagram of the control circuit 200 of the copying machine A.

The control circuit 200 controls the first CP for performing overall control of the copying machine A.
U201, second CPU 221 with clock function, RAM 209, 210, ROM 211
And so on. One RAM 209 is backed up by a main power supply (not shown), and is initialized when the main power supply is turned off. The other RAM 210 is backed up by a battery, and data written in the RAM 210 is retained regardless of whether the main power supply is turned on or off. 212-214 is RAM20
9, 210, and a data bus that connects each of the ROM 211 and the first CPU 201.

The first CPU 201 has an output voltage VD of the surface electrometer 90 described above,
The output voltage VT of the toner density sensor 80 and the output voltage VP of the photosensor 19 are converted into digital signals by A / D converters 205 to 207 and input, respectively, and an exposure lamp for lighting the exposure lamp 21 is provided. The first CPU 20 has a power supply 50 and a high-voltage power supply 40 for applying the developing bias VB.
Control signals are applied from 1 via D / A converters 203,204. Reference numeral 208 denotes a power supply for driving the supply motor 78, and reference numeral 216 denotes an interface for transmitting and receiving data between an operation panel 100 and the first CPU 201 described later.

An online controller 223 communicates with an external management device 227 described below.

FIG. 9 shows the surface voltage VH of the photosensitive drum 5 and the surface potential meter 90.
5 is a graph showing the relationship between the output voltages VD.

As shown in the figure, if the surface voltage VH is 70 volts, the output voltage VD is 0.35 volt, and similarly, the surface voltage VH is
At 350 volts, output voltage VD is 1.75 volts, surface voltage VH
Is 650 volts, the output voltage VD is 3.25 volts. 70, 350, and 650 volts at the surface voltage VH are standard values for each of the light potential VR, gray potential Vi, and dark potential VO in the copying machine A.

The light potential VR is a potential corresponding to a portion that has been neutralized by exposure (a portion corresponding to a white background portion of the document D), and does not become 0 volt due to residual charge even in the best state.
The light potential VR is appropriate if it is 110 volts or less, and 110
It is incorrect but not abnormal up to 150 volts beyond the bolt, and abnormal if it exceeds 150 volts. In addition,
In this embodiment, the potential of the exposed portion corresponding to the adjustment seal 25a is set to the bright potential VR.

The gray potential Vi is a potential of an exposed portion corresponding to the adjustment seal 25b, and the dark potential VO is a potential of a portion corresponding to a non-exposed portion (black portion) on the surface of the photosensitive drum 5.

These gray potential Vi, dark potential VO, and developing bias VB
Is determined based on the light potential VR. That is, the optimal values corresponding to the standard electrophotographic process conditions defined by the shape, material, and the like of the above-described photosensitive drum 5 and the developing device 7 are represented by Expressions (1) to (3).

VB = VR + 150 (1) Vi = VB + 130 (2) VO = VB + 430 (3) FIG. 10 is a diagram showing the set level of the developing bias VB.

As shown in equation (1), the difference between the developing bias VB and the light potential VR is optimally 150 volts. When the voltage is lower than 150 volts, toner adhesion to exposed portions (portions having residual charges), that is, background contamination occurs, and when the voltage is higher than 150 volts, magnetic carriers adhere.

Therefore, in the present embodiment, in order to cope with fluctuations in the light potential VR, nine levels of developing biases VB are provided at a pitch of 10 volts around a level 5 having a standard developing bias VB (220 = 70 + 150 volts) as a target value. Can be set. In the following description, the set level of the developing bias VB is referred to as “VB level”.

FIG. 6 is a graph showing the relationship between the toner weight ratio T / C and the output voltage VT of the toner density sensor 80.

The value of the toner weight ratio T / C specified as the standard electrophotographic process conditions (standard value) is 5 [wt%], and the output voltage VT of the toner density sensor 80 at this time is 2.85 volts. When performing the copying operation using the standard value as the set value of the toner weight ratio T / C, the first CPU 201 compares the output voltage VT with 2.85 volts as the reference potential. When the value of the output voltage VT is larger than `` 2.85 '', that is, when the toner weight ratio T / C is lower than the standard value, the first CPU 201 turns on the power supply 208 of the supply motor 78 to perform toner supply,
Make the toner weight ratio T / C close to the standard value.

The control for maintaining the toner weight ratio T / C at the set value is performed at any time during the copying operation.
The set value of T / C is changed based on a self-diagnosis in an image adjustment process described later.

FIG. 7 is a diagram showing the relationship between the set level of the toner weight ratio T / C and the dark potential VO and the gray potential Vi. In this embodiment,
The set value of the toner weight ratio T / C can be set in four stages of levels 1 to 4. In the following description, the toner weight ratio
The T / C setting level is called "T / C level".

Generally, as the value of the toner weight ratio T / C increases, the developing efficiency increases. Therefore, even when the potential difference between the photosensitive drum 5 and the developing sleeve 71 is reduced, the toner weight ratio T / C is increased. By doing so, it is possible to obtain a hard copy image having an appropriate density. Therefore, in the image adjustment processing described later, when the output adjustment of the charger 6 reaches the limit at the standard toner weight ratio T / C, that is, at the T / C level “1”, the T / C level is changed. You. However, if the toner weight ratio T / C exceeds 8 [wt%], excessive driving torque is applied to bucket rollers and the like,
Further, since an adverse effect such as overflow of the toner from the developing tank 70 occurs, the upper limit of the toner weight ratio T / C is set to 8 [wt%].

 FIG. 11 is a diagram showing a setting level of the exposure amount.

The exposure amount is set by controlling the lighting power supplied from the exposure lamp power supply 50 to the exposure lamp 21. In the copying machine A, nine levels can be set in a range of 1.6 to 2.4 [Lux · sec] centering on level 5 having a target value of 2.00 [Lux · sec]. In the following, the set level of the exposure amount is referred to as “EXP level”.

FIG. 8 is a graph showing the relationship between the output voltage VP of the photosensor 19 and the estimated density ID.

This graph corresponds to the relationship between the density of the toner image on the photosensitive drum 5 and the actually measured density of the hard copy image obtained by transferring and fixing the toner image on the paper P. For example, if the value of the output voltage VP is “2.5”, it can be estimated that the density of the formed hard copy image is 1.0 “Macbeth”. The graph data GD is stored in the ROM 211 in advance.

The first CPU 201 refers to the data in the ROM 211 and calculates the estimated density ID of the hard copy image formed in the copying operation based on the output voltage VP of the photo sensor 19. That is,
Based on the density of the toner image (reflectance of the toner image), which is one of the physical property values associated with the electrophotographic process, the density of the hard copy image that is visually observed by the operator is estimated.

FIG. 12 is a plan view showing an example of the operation panel 100 of the copying machine A.

The operation panel 100 is divided into an operation unit 219a for setting copying conditions such as the number of copies and density, and a display operation unit 219b related to displaying the status of each unit.

The operation unit 219a has a print key 101 for starting a copying operation, and a 7-segment L for displaying the number of copies and the like.
ED102, numeric keypad 10 corresponding to numerical values of 1,2,… 9,0 respectively
4 to 113, a clear / stop key 103 for canceling the setting of copy conditions, up and down keys 114 and 115 for changing and setting the copy image density stepwise, a density display section 116 for displaying the copy image density, and the like. Are located.

The display operation unit 219b includes a message display unit 117 including a liquid crystal display and serviceman keys 118 to 124.
Is arranged.

As will be described later, the serviceman keys 118 to 124
It is mainly used for maintenance by a service person such as a display operation of management information stored in the M210 and a data processing operation. Note that the serviceman keys 118 to 124 may be covered by a cover or provided in the main body so that normal operation cannot be performed.

FIG. 13 is a block diagram showing a schematic configuration of the management network system 500.

The management network system 500 connects five identical copying machines A, A,...
0, and three of the five are installed in the building B1 in which the extension network is configured by the automatic exchange 225a and the internal lines 229a to 229c, and the other two are respectively It is installed in buildings B2 and B3 and is connected to telephone line 230 via automatic exchanges 225a and 225c.

In each of the copying machines A, A,..., The communication processing by the first CPU 201 is executed at appropriate times, and management information indicating the respective operating states is transmitted to the service station SS. Service station
In the SS, the sent management information is input to the management device 227 via the automatic exchange 226. Serviceman is management device 2
By displaying or printing the management information of each copying machine A, A... Inputted to 27, the operating state of each copying machine A, A. Thus, it is possible to determine whether maintenance is necessary for each of the copying machines A, A,... At a location different from the installation location of each of the copying machines A, A,.

Next, the operation of the copier A will be described with reference to the flowcharts of FIGS.

FIG. 14 is a main flowchart schematically showing the operation of the first CPU 201.

When the power is turned on and the program starts, first, in step # 1, initialization of each unit is performed.
In step 2, an internal timer for setting the length of one routine of the first CPU 201 is set.

In step # 3, an input process of receiving signals from the operation keys of the operation panel 100, sensors and switches of each unit is performed.

Subsequently, image adjustment processing (step # 4), warning display /
Copy prohibition processing (step # 5), data writing processing (step # 6), data display processing (step # 7),
After sequentially executing the data transmission process (step # 8),
In step # 9, a copying operation is performed.

In the next step # 10, communication processing with the second CPU 221 is performed.

After executing these processes, in step # 11, the internal timer is waited for, and the process returns to step # 2. As a result, while the length of one routine is kept constant and the power is turned on, the processing of steps # 2 to # 11 is repeated.

FIGS. 15 (a) to (d) are flowcharts of the image adjustment processing in step # 4 described above.

In this routine, the operation state of the copying machine A is
Setting processing for image adjustment (state “1” to state) in which settings are made for each device around the photosensitive drum 5 based on a self-diagnosis that determines whether the state is an improper state or an abnormal state “15”) and a state storage process (state “16” to state “22”) for storing state data indicating the state of each unit obtained by the self-diagnosis.

In this routine, first, the state is checked in step # 101, and the following processing is executed according to the state.

In the state "1", the current T / C level is read from the RAM 209 in step # 111.

Next, whether the T / C level is "1",
It is checked whether or not the standard T / C level is set (step # 112). If yes, the state is set to "2" in step # 113. If no in step # 112, in step # 114, the T / C level is set to "1", and then step # 113 is executed.

In state "2", in step # 121, the charging charger 6 is turned on to rotate the photosensitive drum 5, and the HV
The levels are sequentially changed to measure the dark potential VO at each of the HV levels “1” to “9”.

In step # 122, the HV level at which the measured value in step # 121, that is, the value of the output voltage VD of the surface electrometer 90 becomes the value closest to 3.25 volts corresponding to the standard value (650 volts) of the dark potential VO Select “x1” (any of HV levels “1” to “9”). Then, the state is set to "3" (step # 123).

In the state “3”, the output voltage at the HV level “x1” selected in the previous state “2” in step # 131
Check if the VD value "VDx1" is greater than or equal to 2.0 volts. That is, it is checked whether or not the dark potential VO is equal to or higher than the lower limit (400 volts) that enables the copying operation.
If yes in step # 131, the HV level "x1" is set as the provisional HV level in step # 132.

If NO in step # 131, a serious trouble (trouble) such as disconnection of the charge wire 61 of the charger 6 has occurred, and it is impossible to execute the copying operation.
That is, the operation state of the copying machine A is abnormal. In this case, the state is set to "21" (step # 13).
Four).

In the state "4", the slider unit 24 of the optical system 20 is stopped at the above-described adjustment position Y1 (step # 14).
1) The state is set to "5" (step # 142).

In state "5", first, step # 151
Then, the EXP level is sequentially changed to irradiate the adjustment seal 25a to measure the light potential VR at each EXP level “1” to “9”.

Next, in step # 152, the value of the output voltage VD of the surface voltmeter 90, which is the measured value in step # 151, is a value closest to 0.35 volt corresponding to the standard value of the light potential VR (70 volts). EXP level "x2". Then, the state is set to "6" (step # 153).

In state "6", in step # 161, it is checked whether the value "VDx2" of the output voltage VD at the EXP level "x2" is 0.75 volt or less. That is, it is checked whether or not the light potential VR is equal to or lower than the upper limit (150 volts) at which the copying operation is possible.

If no in step # 161, a trouble such as a failure of the exposure lamp 21 has occurred, and the copying operation is impossible. That is, the operation state of the copying machine A is abnormal. In this case, the process proceeds to step # 166, where the state is set to "22".

If yes in step # 161, in step # 162,
The EXP level “x2” is set as the temporary EXP level.

In a succeeding step # 163, it is determined whether or not the actually measured value "VDx2" is equal to or less than 0.55 volt.

If “YES” in the step # 163, the developing bias VB satisfying the above-described expression (1) can be set, and a copy image with appropriate image quality can be formed. The operation state of the copying machine A is an appropriate state. In this case, the state is set to "7" in step # 164.

If no in step # 163, the copying operation can be executed, but it is impossible to set the developing bias VB that satisfies the formula (1) even if the adjustment limit VB level "9" is selected. Therefore, the image quality of the copied image may be inappropriate. Therefore, the operation state of the copying machine A becomes an inappropriate state. In this case, the state is set to "18" (step # 165).

In state "7", a developing bias VB, which is one of the electrophotographic process conditions, is determined.

That is, the light potential VR corresponding to the above-described actually measured value “VDx2”
Is calculated, and the target value of the developing bias VB is set to “VRx2”.
Select the VB level “x3” closest to “x2 + 150” volts (step # 171) and set the VB level “x3” as the VB level
Is set (step # 172). For example, the measured value "VDx
If "2" is 0.35 volts, the value "VRx2" of the light potential VR corresponding to this is 70 volts of the optimum value (see FIG. 9), and the VB level "220 (70 + 150) volts as the target value" 5 "(see FIG. 10) is set. Then, in step # 173, the state is set to "8".

In state "8", first, in step # 181
Then, the value "VBx3" of the developing bias VB at the VB level "x3" is substituted into Expression (3) to calculate the calculated value "VDx4" of the output voltage VD corresponding to the target value "VOx4" of the dark potential VO. .

Next, in step # 182, the value "VBx3" is substituted into the equation (2) to calculate the calculated value "VDx6" of the output voltage VD corresponding to the target value "Vix6" of the gray potential Vi. And step #
At 183, the state is set to “9”.

In the state “9”, the HV level “x5” whose measured value (the value of the output voltage VD) in the step # 121 of the state “2” is closest to the calculated value “VDx4” is selected (step # 191). The state is set to "10" (step # 192).

In state "10", first in step # 201,
It is confirmed whether or not the actual dark potential VO is a value within an appropriate range determined according to the target value obtained by calculation. That is,
Actual measured value of output voltage VD corresponding to HV level "x5""VDx5"
It is checked whether or not the relationship between the calculated value and the calculated value “VDx4” satisfies the following expression (4).

VDx5 ≧ VDx4−0.25 [V] (4) The difference of 0.25 volts in the output voltage VD is the surface potential.
When converted to VH, the difference is 50 volts.

If yes in step # 201, since the dark potential VO is appropriate, the HV level “x5” is set as the HV level (step # 202), and the state is set to “11” (step # 2)
03).

If the answer is no in step # 201, the state is set to "14" in step # 204. In this case, the dark potential VO is lower than an appropriate value, and the operation state is an inappropriate state. If a copying operation is performed in this inappropriate state, a faint image is formed with little toner adhesion.

In state "11", the slider unit 24 is stopped at the adjustment position Y2 (step # 211), and the state is set to "1".
2 "(step # 212).

In state "12", first, step # 221
Then, the EXP level is sequentially changed to irradiate the adjustment seal 25b, and the gray potential Vi at each EXP level “1” to “9” is obtained.
Measurement.

Next, the output voltage V which is the measurement value in the previous step # 221
E where the value of D is the closest to the above calculated value "VDx6"
The XP level “x7” is selected (step # 221), and the EXP level “x7” is set as the EXP level (step # 222).
Then, in step # 223, the state is set to "13".

In the state “13”, in step # 231, it is checked whether or not the actual gray potential Vi is a value (Vix6 ± 10 volts) within an appropriate range determined according to the target value “Vix6” calculated. That is, the relationship between the measured value “VDx7” and the calculated value “VDx6” of the output voltage VD corresponding to the EXP level “x7” is
It is checked whether the following expression (5) is satisfied.

VDx6−0.05 ≦ VDx7 ≦ VDx6 + 0.05 [V] (5) If yes in step # 231, the gray potential VO is appropriate, and the flow advances to step # 232 to set the state to “16”.

If NO in step # 231, the gray potential VO is inappropriate, and the state is set to "17" in step # 233.

State “14” is executed when it is determined in the above state “10” that the dark potential VO is inappropriate.
In step # 241, charger flag F _CH showing the cleaning status of the charge wire 61 checks whether or not "0".

If yes in step # 241, charge wire 61
Is not cleaned, and the cause of the improper dark potential VO is considered to be contamination of the charge wire 61. Therefore, in step # 242, cleaning of the charge wire 61 is executed. Then, in step # 243, the charger flag F _{CH is set} to “1”.
And the state is set to “2” in step # 244. Therefore, if yes in step # 241,
With the dirt on the charge wire 61 removed, the processes after the state “2” are executed again.

If no in step # 241, charge wire 6 is already
This is a case where an appropriate dark potential VO cannot be obtained despite the cleaning of 1. In this case, step # 245
And the state is set to “15”.

In state "15", first, step # 251
Then, it is checked whether or not the number of changes n of the T / C level is “3”.

If no in step # 251, the process proceeds to step # 252 to increase the T / C level by one level. That is, the setting of the T / C level is changed so that the toner weight ratio T / C increases. For example, the current setting is T / C level "1"
If so, change to T / C level “2”. Next, in step # 253, the number of changes n is set to a value obtained by adding 1 to the current value,
At step # 254, the state is set to "8".

Therefore, if no in step # 251, the seventh
As shown in the figure, the dark potential V corresponding to the new T / C level
The target values of O and the gray potential Vi are calculated, and the HV level and EX are set so that an appropriate image is obtained based on the target values.
P level setting is performed.

If yes at step # 251, T / C level as T / C
This is the case where the C level “4” is set, and since the T / C level has already reached the adjustment limit, the T / C level is not changed, and the state is set to “19” in step # 255.

In state "16", it is checked in step # 261 whether the number of changes n is "0". If yes in step # 261, standard T / C as T / C level
Since level “1” has been set, step # 262
The state data C _OK indicating that the T / C level is appropriate is stored. The storage in this routine is performed by storing data in the RAM 209.

If no at step # 261, at step # 264
State data _{CT / C} indicating that the T / C level is inappropriate is stored. After execution of step # 262 or step # 264, the state is set to "20" in step # 263.

In state "17", it is checked in step # 271 whether the number of changes n is "0", and if yes, state data C _Vi indicating that the gray potential Vi is inappropriate is stored. (Step # 272), and if no, the state data C _Vi and the state data _{CT / C} are stored (step # 272).
273). After execution of step # 272 or step # 273,
Go to step # 263 described above.

In state "18", state data _CVR indicating that the light potential VR is inappropriate is stored (step # 275),
Go to step # 263 described above.

In state "19", state data _CVO indicating that the dark potential VO is inappropriate is stored (step # 276).
Go to step # 263 described above.

In the state “20”, a process for estimating the density of the hard copy image under the electrophotographic process conditions set as described above is executed.

That is, in step # 281, the toner image formed by turning off the exposure lamp 21 (toner image corresponding to black), and the toner image formed by turning on the exposure lamp 21 at the adjustment position Y1 (toner image corresponding to white) , And exposure lamp at adjustment position Y2
The photosensor 19 is used to measure the densities of three types of toner images formed by turning on the light source 21 (toner image corresponding to gray).

Next, in step # 282, based on the output voltage VP of the photosensor 19 and the graph data GD1 stored in the ROM 211, a calculation is performed to obtain an estimated density ID of the hard copy image, and black, white, and gray The estimated density data ID _O , ID _R , and ID _i are calculated for each of the three types of hard copy images.

Thereafter, in step # 283, the image adjustment end flag FC for indicating that the setting for each device around the photosensitive drum 5 has been completed is set to "1".

In state "21", in step # 291, based on the self-diagnosis in state "3" described above, state data _CCH indicating that charging charger 6 is in an abnormal state is stored. Then, in step # 292, the image adjustment end flag F
Set C to "1".

In the state "22", based on the self-diagnosis in the state "6", state data C _EXP indicating that the exposure lamp 21 is in an abnormal state is stored (step # 293).
Go to step # 292 described above.

FIG. 16 is a flowchart of the warning display / copy prohibition process in step # 5 of FIG.

Also in this routine, first, the state is checked in step # 301, and the following processing is executed according to the state.

In state "31", in step # 311 the signal S
Check for the input of 1. The signal S1 is
When the up key 114 or the down key 115 of 00 is pressed, it is input to the first CPU 201 via the interface 216. If no in step # 311, in step # 315,
The state is "32".

If the answer is YES in step # 311, the operator has set the density which is one element of the image quality. In this case, it is considered that the operator pays particular attention to the image quality. For this reason, when the operation state of the copying machine A is improper, it is necessary to inform the operator before the start of the copying operation that it is difficult to form a copied image of the desired image quality.

Therefore, in steps # 312 to # 314, it is checked whether or not the state data C _Vi , C _VR , and C _VO are respectively stored, that is, whether or not each data is in the RAM 209.
If the determination in any of Steps # 312 to # 314 is YES, the operation state of the copying machine A is improper. In this case, the process proceeds to step # 316.

At step # 316, a warning is displayed on the message display section 117 of the operation panel 100 indicating that the operation state of the copying machine A is improper.

FIGS. 22 (a) to (k) show examples of the display screen of the message display unit 117. FIG.

FIG. 22 (a) shows the display screen when it is determined to be Yes in step # 312, and the message "C _Vi " indicating an improper part is displayed together with the message Z1 in the improper state. ing. If it is determined that the answer is yes also in steps # 313 and 314, the characters " _CVR " and " _CVO " are additionally displayed.

In the state "32", first, step # 321
Then, it is checked whether or not the state data _CCH has been stored.
A warning display of an abnormal state shown in FIG. In this case, the message " _ZCH " indicating the trouble location (abnormal location) is displayed together with the message Z2 in the abnormal state.

Next, in step # 323, a copy prohibition process for prohibiting the start of the copy operation is executed. That is, control is performed to prohibit the input of each of the keys 101, 103 to 115 of the operation panel 100 and to turn off the power of each unit except for a device related to data processing.

Thereafter, in step # 324, the state is updated to "33".

In the state "33", first, step # 331
Then, it is checked whether or not the state data C _EXP is stored.
A warning display of the abnormal state shown in FIG. In this case, the character "C _EXP " indicating the trouble part is displayed. At this time, if the warning display of “C _CH ” has already been made in step # 322, the character display of “C _EXP ” is displayed below “C _CH ”.

In step # 333, the same copy prohibition process as in step # 323 is performed, and in step # 334, the state is returned to "31".

FIGS. 17 (a) to (c) are flowcharts of the data writing process in step # 6 of FIG.

At step # 401, the state is checked, and the following processing is executed according to the state.

In state "41", first, in step # 411
Then, it is determined whether or not a write end flag FRAM indicating the end of this routine is “0”. If no in step # 411, that is, if the write end flag FRAM is "1", the process immediately returns to the main routine. By executing the step # 411, the subsequent processes are executed only once after the above-described image adjustment process.

If yes in step # 411, then in step # 412,
It is checked whether or not the image adjustment end flag FC is “0”.

If no in step # 412, that is, if the image adjustment end flag FC is "1", the image adjustment end flag FC is set to "0" in step # 413, and the process proceeds to step # 414.

In step # 414, date / time data TD indicating time information such as date and day of the week is read from the second CPU 221. afterwards,
The write end flag FRAM is set to "1" (step # 41)
5) The state is set to "42" (step # 416).

In state "42", in step # 421, the RAM 20
It is checked whether or not the state data C _Vi is stored in 9.

If yes in step # 421, then in step # 422,
As described later, the RAM 210 responds to the improper gray potential Vi.
Count data k1 indicating the number of times the date / time data TD has been written to
Read from RAM 210.

Next, “1” is added to the value of the read count data k1 to obtain new count data k1 (step # 423), and the new count data k1 is written to the RAM 210.

Subsequently, in step # 425, the date and time data TD read out in step # 424 described above is associated with the state data C _{Vi in} R
Write to AM210, state # 43 in step # 426
Update to

In the states "43" to "47", the same processing as in the state "42" is performed corresponding to the respective state data C _{T / C} , C _VR , C _VO , C _CH , and C _EXP .

That is, the state data C _{T / C} , C _VR , C _VO ,
Checking whether C _CH and C _EXP are stored (Steps # 431, 441,
451,461,471), reading of the count data k2 to 6 (steps # 432,442,452,462,472), updating of the count data k2 to 6 (steps # 433,443,453,463,473), and count data k2 to
6 (steps # 434, 444, 454, 464, 474) and date / time data TD (steps # 435, 445, 455, 465, 47).
5) Update state (steps # 436,446,456,466,47)
6) is executed.

In the state “48”, the processing number data N indicating the number of times the image adjustment processing has been executed is read from the RAM 210 (step # 481), and “1” is added to the processing number data N to update the value (step # 482). ), The updated number-of-times-of-processing data N is written into the RAM 210 (step # 483), and the state is set to "49" (step # 484).

In the state “49”, the state data C _OK , C _Vi , C _{T / C} , C _VR ,
It is checked whether or not each of the C _VOs is stored in the RAM 209. If no state data is stored, the state is set to "50" in step # 496.

If the answer is YES in any of steps # 491 to # 495, the management data CD1 for confirming the aging of the operation state of the copying machine A is written in the RAM 210 in step # 497.

The management data CD1 includes date and time data TD, state data determined to be YES in steps # 491 to # 495, and three types of surface potentials VH (dark potential VO, gray potential Vi, the final measure of bright potential VR), each set level (VB, T / C, HV , EXP), and the estimated density data ID _O, I
D _i and ID _R.

In the state "50", it is checked whether or not the state data _CCH is stored (step # 501). If yes, the management data CD2 is written in the RAM 210 (step # 502), and the state is set to "51". (Step # 50
3).

The management data CD2 includes date and time data TD, state data C _CH , the final measured value of the dark potential VO measured after the end of the image adjustment processing, and the HV level.

In the state “51”, the state data C _{EXP is} stored in the RAM _209.
Is checked (step # 51).
1) If yes, write the management data CD3 into the RAM 210 (step # 512) and set the state to "52" (step # 513).

The management data CD3 includes date and time data TD, status data C _EXP ,
It consists of the final measured values of the dark potential VO and the light potential VR measured after the end of the image adjustment processing, the HV level and the EXP level.

As described above, the management data CD1 to CD3 have the minimum information that enables identification of the cause of the operation state of the copying machine A being in an improper state. The content item differs depending on whether the content is inappropriate. This makes it possible to reduce the capacity of the RAM 210, simplify the display described later, and increase the efficiency of data transmission to the management device 227.

In the state “52” to the state “54”, processes related to periodic data erasure or data initialization for improving the use efficiency of the memory of the RAM 210 are executed.

In state "52", first, step # 521
Then, the management data CD1 to CD3 written in the past are read from the RAM 210.

Next, in step # 522, the read management data CD1
It is determined whether .about.3 are written on a specific day of the week, for example, Monday (hereinafter, referred to as "Monday").

If yes in step # 522, then in step # 525,
It is determined whether it is within the past two months. If yes in step # 525, the data is not erased.
In step # 526, the state is updated.

If no in step # 522, it is determined in step # 523 whether the current time is within the past week. If yes in step # 523, proceed to step # 526.

If no in step # 523 or step # 525,
At step # 524, unnecessary management data CD1 to CD3 are deleted.

As a result, only the daily items within the past one week and every Monday within the past two months are continuously stored in the RAM 210.

In the state “53”, first, the date / time data TD written in association with each state data in the above-mentioned states “42” to “47” is read from the RAM 210.

Next, in step # 532, it is determined whether the date is within the past year. If yes in step # 532,
Without erasing the data, the state is updated in step # 534.

If no in step # 532, the unnecessary date and time data TD is deleted in step # 533.

As a result, only the date / time data TD within the past year is continuously stored in the RAM 210.

In state “54”, in step # 541, the signal S
Check if 2 has been entered.

The signal S2 is input to the first CPU 201 when the serviceman key 118 is pressed and when the initialization control signal S2 is applied to the copying machine A from the management device 227.

If no in step # 541, the state is returned to "41" in step # 543.

If No in step # 541, initialization is performed to set the values of the number-of-times data k1 to 6 and the number-of-times-of-processing data N to "0" in step # 542, and the process proceeds to step # 543.

FIGS. 18 (a) to 18 (d) are flowcharts of the data display process in step # 7 of FIG.

First, in step # 601, a state check is performed, and the following processing is executed according to the state.

In the state "61", in a step # 611, it is checked whether or not the processing flag FS3 indicating the execution progress of this routine is "0".

If no in step # 611, the process proceeds to step # 616 to update the state to "62". If yes, the process proceeds to step # 612.

At step # 612, the presence or absence of the input of the signal S3 is checked. Signal S3 is input to first CPU 201 when serviceman key 119 is pressed. If yes in step # 612, proceed to step # 613; if no, proceed to step # 616.

In step # 613, the data of the current day (the execution date of this routine) in the management data CD1 to CD3 is read from the RAM 210, and the data is displayed on the message display unit 117.

FIGS. 22 (d) and (g) show screens displayed based on the management data CD1 corresponding to the proper state and the inappropriate state, respectively. FIGS. 22 (e) and (f) show the management data CD2 and 13 shows a screen displayed based on CD3. In these figures, 301 is the date, 302 is the character corresponding to the status data, 303 to 305 are the final measured values, 306 to 309 are the set level values, and 310 is the estimated density value.

Next, in step # 614, an identification symbol 300, for example, a black triangle as shown in FIGS. 22 (e) to (g) is displayed near the display character corresponding to the incorrect item on the display screen. .
This makes it possible to easily confirm whether each item is appropriate or inappropriate.

 At step # 615, the processing flag FS3 is set to "1".

In the states “62” to “68”, the value of the processing flag FS3 and the presence / absence of the input of the signal S3 are checked as in the state “62”. Also, the management data CD1 ~
Among the three, the previous day, the day before, the day before, the day before, the day before,..., The day before 6 days and the day before 7 days are read and displayed, respectively.

That is, every time the serviceman presses the serviceman key 119, the displayed management data CD1 to CD3 is further changed to that of one day before. Further, when the key 119 is pressed while the one before seven days is displayed, the one on the day is displayed again.

In the state “69”, in step # 651, the signal S
Check the input of 4.

The signal S4 is input when the serviceman keys 118, 120 to 124 other than the clear / stop key 103 or the key 119 are pressed.

If “YES” in the step # 651, the process flag FS3 is returned to “0” in a step # 652.

Thus, for example, the display of the management data CD1 to CD3 can be stopped by pressing the clear / stop key 103. When the clear / stop key 103 is pressed and then the service key 119 is pressed, even if the message 2-7 days ago is displayed, the message can be immediately changed to the current day.

In the state “70”, it is checked in a step # 661 whether or not the processing flag FS5 is “0”.

If no in step # 661, the process proceeds to step # 666 to update the state to "71". If yes, the process proceeds to step # 662.

At step # 662, the presence or absence of the input of the signal S5 is checked. The signal S5 is input when the serviceman key 120 is pressed. If yes in step # 662, proceed to step # 663; if no, step # 666 above
Move to

In step # 663, the data of Monday one week ago among the management data CD1 to CD3 is read from the RAM 210 and displayed on the message display unit 117.

Next, in step # 664, the above-described identification symbol 300 is displayed near a display character corresponding to an incorrect item on the display screen.

At step # 665, the processing flag FS5 is updated to "1".

In the states “71” to “78”, similarly to the state “70”, the value of the processing flag FS5 and the presence or absence of the input of the signal S5 are checked. Also, the management data CD1 ~
Among the three items, one week ago, two weeks ago... Eight weeks ago, each Monday is read out and displayed, and an improper item is given an identification symbol 300.

That is, every time the serviceman presses the serviceman key 120, the displayed management data CD1 to CD3 are further replaced with the management data CD1 for one week ago. Further, when the key 120 is further pressed while the one eight weeks ago is displayed, Monday one week ago is displayed again.

In the state “79”, in step # 691, the signal S
Check the input of 6.

The signal S6 is input when the clear / stop key 103 or any of the serviceman keys 118, 119, 121 to 124 other than the key 120 is pressed. If "YES" in the step # 691, the process flag FS5 is returned to "0" in a step # 692. Thus, for example, the display of the management data CD1 to CD3 can be stopped by pressing the clear / stop key 103.

In state “80”, in step # 701, the signal S
Check the input of 7. Signal S7 is input when serviceman key 121 is pressed. Step # 7
If NO in 01, the process proceeds to step # 703 to update the state, and if yes, the process proceeds to step # 702.

In step # 702, the number-of-times data k1 to k6 and the number-of-times-of-processing data N are read from the RAM 210, and the read data is displayed on the message display unit 117.

FIG. 22 (h) shows a display screen in the process of step # 702. In the figure, reference numerals 313 to 319 denote numbers indicating the values of the number-of-times data k1 to k6 and the number-of-times-of-processing data N, respectively. Reference numeral 311 denotes the date on which the counting of these data k1 to N was started after the data k1 to N were initialized.

In the state “81”, in step # 711, the signal S
Check the input of 8. Signal S8 is input when serviceman key 122 is pressed. Step # 7
If no in step 11, the process proceeds to step # 713 to update the state. If yes, the process proceeds to step # 712.

In step # 712, the state data C _Vi , C _{T / C} , C _VR , C _VO , C _CH , C _EXP corresponding to the improper state and the abnormal state and the dates in which these are stored are arranged and displayed in order of date. FIG. 22 (i) shows a display screen in the process of step # 712, where 400 in FIG. 22 is the date (month and day) when each state data was stored.
It is.

In the state “82”, in step # 721, the signal S
Check if 9 is entered. Signal S9 is input when serviceman key 123 is pressed. Step # 7
If NO in step 21, the process proceeds to step # 723 to update the state. If yes, the process proceeds to step # 722.
In step # 722, the processing flag FS9 is set to "1".

In the state “83”, it is checked in a step # 731 whether or not the processing flag FS9 is “0”. If “YES”, the process proceeds to a step # 759 to update the state.

If No in step # 731, that is, if the service person key 123 is pressed, the presence or absence of the input of the signals S21 to S28 is sequentially checked in steps # 732 to # 739. The signals S21 to S28 and a signal S29 described later are
Input is performed in response to the operations 4 to 112.

If the answer is YES in Steps # 732 to # 739, the process proceeds to Steps # 751 to # 758, respectively.

In steps # 751 to # 758, the past 1
Dark potential VO, gray potential Vi, light potential VR, VB every day of the week
The level, the T / C level, the HV level, the EXP level, and the estimated concentration ID are graphed (schematically) in time series and displayed on the message display unit 117. As a result, the service person can confirm the change in the operating state in the past week for each item of the self-diagnosis.

FIG. 22 (j) shows the display screen at step # 751. In the figure, 320 is a horizontal line indicating the optimum value of the dark potential VO, 321 and 322 are horizontal lines indicating the upper limit value and the lower limit value of the appropriate range, 323 to 329 are vertical lines indicating the day (today, the previous day ... 6 days ago), 330 to 336 are plots showing the value of the dark potential VO on each day. In the example of FIG. 22 (j), the value of the dark potential VO was the optimal value six days ago, but gradually decreased thereafter, and has fallen below the lower limit today. For this reason, the identification symbol 300 is displayed above the vertical line 323.

If all are negative in steps # 732 to # 739, it is checked in step # 740 whether the signal S29 has been input. The signal S29 is input when the serviceman keys 118 to 122, 124 except the clear / stop key 103 and the key 123 are pressed.

If yes in step # 740, then in step # 741,
The processing flag FS9 is reset to "0", and the routine goes to Step # 759.

In state “84”, in step # 761, the signal S
Check for the presence of 10 inputs. Signal S10 is input when serviceman key 124 is pressed. If no in step # 761, the process returns to the main routine.

If yes in step # 761, then in step # 762,
The processing flag FS10 is set to “1”, and in step # 763, the state is updated to “85”.

In the state "85", in a step # 771, it is checked whether or not the processing flag FS10 is "0". If yes, the process proceeds to a step # 799 to change the state to "61".
Return to

If the determination in step # 771 is NO, that is, if the service key 124 is pressed, the signals S21 to S28 are determined in steps # 772 to # 779 similarly to the state "83".
Are checked sequentially.

If the answer is yes in steps # 772 to # 779, the process proceeds to steps # 791 to # 798, respectively.

In steps # 791 to # 798, the past 2
Dark potential VO, gray potential Vi, light potential VR, VB level, T / C level, HV level, EXP level,
And the estimated concentration ID are graphed in time series and displayed on the message display unit 117. As a result, the service person can check the change in the operating state in the past two months (8 weeks) for each self-diagnosis item.

FIG. 22 (k) shows the display screen at step # 791. In the same figure, 320 to 322 indicate horizontal lines similar to those in FIG. 22 (j), 342 to 349 indicate vertical lines indicating the week (this week, last week, two weeks before ...), and 359 to 366 indicate the value of the dark potential VO of each week. It is a plot.

If all are NO in steps # 772 to # 779, it is checked in step # 780 whether or not the signal S30 has been input. If yes, in step # 781, the processing flag FS1
“0” is reset to “0”, and the routine goes to the above-mentioned step # 799.
The signal S30 is transmitted to the clear stop key 103 and the key 12
This signal is input when any of the serviceman keys 118 to 123 except 5 is pressed.

FIG. 19 is a flowchart of the data transmission process in step # 8 of FIG.

In this routine, corresponding management information is sent to the management device 227 at a predetermined time for each self-diagnosis item according to the necessity of management of the operation state of the copying machine A.

First, in step # 901, a state check is performed, and the following processing is executed according to the state.

In the state “91”, first, in steps # 911 to # 913, signals S11 to S913 are used to confirm whether it is time to transmit data (day of the week, time).
Are checked sequentially. The signals S11 and S12 are input from the second CPU 221 at a predetermined time as described later, and the signal S13 is input when a control signal instructing data transmission is added from the management device 227.

If the answer is yes in step # 911, the process proceeds to step # 915. If the answer is no in step # 911 and the answer is yes in step # 912, the process proceeds to step # 914.

If no in step # 913, that is, signals S11 to S13
If none of the above is input, step # 920
Move to and update the state.

In steps # 914 to # 918, the diagnostic results of each item of the self-diagnosis are checked. That is, status data C _OK , C _Vi , C _{T / C} ,
It is determined whether or not C _VR and C _VO are stored. If yes in any of steps # 914 to # 918,
Proceed to step # 919, and if no, move to step # 920.

In step # 919, the management data CD1 is transmitted to the management device 227 via the online controller 223.

In other words, by executing this state “91”, if there is an inappropriate item, the management information is sent to the management device 227 every day at 10:00 am regardless of the day of the week.
If there is no inappropriate item, the management information is sent at 10:00 am on every Monday and Thursday.

In the state "92", it is checked in step # 921 whether or not the state data _CCH is stored, and if no, the state is updated (step # 923).
Return to the main routine. If “YES” in the step # 921, the management data CD2 is transmitted to the management device 227 in a step # 923.

In the state "23", it is checked in step # 931 whether or not the state data C _EXP is stored, and if no, the state is updated (step # 933).
Return to the main routine. If “YES” in the step # 931, the management data CD3 is transmitted to the management device 227 in a step # 923.

That is, the state “92” and the state “93” are processes for coping with the abnormal state, and in the abnormal state,
Regardless of the date and time and the presence or absence of an instruction from the management device 227, data indicating the content of the abnormal state is transmitted to the management device 227. This allows for quick maintenance work,
Downtime (failure time) of the copying machine A is reduced.

FIG. 20 is a main flowchart schematically showing the operation of the second CPU 221.

When the program starts, initialization of each part (Step # 51), setting of internal timer (Step # 52),
Input processing (step # 53), timing processing (step # 5)
4), and then, in step # 55, the first
The communication processing with the CPU 201 is executed. After executing these processes, in step # 56, the internal timer is waited for, and the process returns to step # 52. The second CPU 221 is backed up by a battery, and the clock function is maintained even when the main body power is turned off.

FIG. 21 is a flowchart of a communication process with the first CPU 201 in the above-described step # 55.

In this routine, first, the state is checked in step # 61, and the following processing is executed according to the state.

In the state "101", the date and time data TD indicating the current date, day of the week, and time are transmitted in step # 62, and the state is set to "102" in step # 63.

In the state "102", in step # 71, it is checked whether or not the current time is, for example, 10:00 am (AM10: 00). If no, the state is changed to "101" in step # 76. return.

If yes in step # 71, that is, if it is 10:00 am, it is determined in next step # 72 whether or not it is Monday. If it is not Monday, it is determined in next step # 73 whether it is Thursday. According to these determinations, if the current day is Monday or Thursday, the state is set to “104”.
(Step # 75), and in the case of another day, the state is set to "103" (step # 74).

In state “103”, in step # 81, the first CP
The signal S11 is transmitted to U201. That is, the signal S11 is transmitted today on a day other than Monday and Thursday. After execution of step # 81, step # 82
Then, the state is returned to “101”.

In state “104”, the first CP
The signal S12 is transmitted to U201. That is, the signal S12 is transmitted today on Monday or Thursday. After execution of step # 91, the state is returned to "101" in step # 92.

In the above embodiment, the predetermined management information is stored in the management device 22.
The time of transmission to 7 can be arbitrarily selected according to the actual situation of management.

In the above-described embodiment, the management information generated every day is stored in the fixed RAM 210. However, the management information is stored using a storage medium detachable from the copying machine A, for example, an IC card. It may be. In this case, it is possible to analyze the condition of the copying machine A using a dedicated data processing device carried by a service person for maintenance.

〔The invention's effect〕

According to the first aspect of the present invention, it is possible to determine the cause of the change in the image quality of the formed hard copy image and take an appropriate measure to obtain the appropriate image quality. In addition, by storing management information indicating the contents of the improper state, the service technician can know that the apparatus is operable but is in an improper operation state at the time of periodic inspection or the like. By taking appropriate measures, it is possible to prevent a problem that the image forming apparatus suddenly shuts down during use by a user.

According to the second aspect of the present invention, in addition to the above-described effects, there is no need to separately prepare a dedicated management information reading device, and not only a service person but also a user can easily change the condition of the image forming apparatus as necessary. You can check.

According to the invention of claim 3, in addition to the effect of the invention of claim 1, it is possible to detect the condition of the image forming apparatus at a location away from the installation location, and to speed up maintenance work.

[Brief description of the drawings]

FIG. 1 is a sectional front view showing a main part of a copying machine, FIG. 2 is an enlarged view of a part of an optical system, FIG. 3 is a view showing a configuration of a charging charger and an output circuit, and FIG. FIG. 5 is a block diagram of a control circuit of a copying machine, FIG. 6 is a graph showing a relationship between a toner weight ratio and an output voltage of a toner density sensor, and FIG. FIG. 8 is a graph showing the relationship between the set level and the dark potential and the gray potential. FIG. 8 is a graph showing the relationship between the output voltage of the photosensor and the estimated density. FIG. 9 is a graph showing the relationship between the surface potential of the photosensitive drum and the output voltage of the surface voltmeter. FIG. 10 is a graph showing the relationship between the developing bias, FIG. 11 is a diagram showing the setting level of the exposure amount, FIG. 12 is a plan view showing an example of the operation panel of the copying machine, and FIG. Is a block diagram showing the schematic configuration of the management network system. Figure flowchart FIG. 14-FIG. 21 showing the operation of the copier, showing the 22 (a) ~ (k) is a diagram showing an example of a display screen of the message display section. 90 surface electrometer (sensor means), 117 message display section (display means), 201 first CPU (self-diagnosis means), 210 RAM (storage means), 223 online controller (communication means) ), 227: management device, A: copying machine (image forming device), CD1 to 3: management data (management information).

Continuation of the front page (56) References JP-A-1-92765 (JP, A) JP-A-62-90668 (JP, A) JP-A-62-115473 (JP, A) JP-A-59-81656 (JP, A) , A) Japanese Utility Model 60-169643 (JP, U) Japanese Utility Model 63-20156 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03G 21/00 370-540 B41J 29 / 38 H04N 1/00 106

Claims (3)

(57) [Claims] 1. An image forming apparatus for forming a hard copy image by using an electrophotographic process, wherein a sensor means for measuring a physical property value associated with the electrophotographic process, and an output of the sensor means is compared with a first threshold value. And determining whether the image forming apparatus is inoperable and operable, and comparing the output with the second threshold value in the operable state to determine whether the image forming apparatus has an appropriate image quality. An image forming apparatus comprising: a self-diagnosis unit that determines whether the state is incorrect or an improper state; and a storage unit that stores management information indicating the contents of the improper state. 2. The image forming apparatus according to claim 1, further comprising display means for displaying each of the management information. 3. The image forming apparatus according to claim 1, further comprising communication means for transmitting the management information to an external management apparatus for managing the operation state of the image forming apparatus.