JPH06214516A - Method for preventing monitor screen burning for production control display system - Google Patents

Abstract

PURPOSE:To surely prevent the burning in the screen of a CRT display device while maintaining a condition where a required display is performed on the screen of the CRT display device monitoring the display contents on a display provided on a production line. CONSTITUTION:The production control information, etc., are displayed on the display provided on the production line. The picture (monitor picture) with the same contents as the display picture on the display is displayed on the CRT display device. The monitor picture is displayed smaller than the picture of the CRT display device, and the display position is revised at every prescribed time. Thus, even when the same display is displayed on the same position on the display picture of the CRT display device, the display position is changed on the picture of the CRT display device, and the burning of the screen is prevented surely.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing image sticking on a monitor screen of a production management display system, and more specifically, a CRT display device for a display screen monitor of a display installed on a production line in a factory and displaying production management information and the like. The present invention relates to a method for preventing screen burn-in.

[0002]

2. Description of the Related Art In a production site of a factory that manufactures automobiles and machines, when an abnormality occurs in each process of a production line, the abnormality is swiftly dealt with to reduce the influence on the next process, or As a substitute when the worker temporarily leaves the place due to a toilet break or the like, a support staff stands by in addition to the worker who performs a predetermined process work.

[0003] In general, in a production site of a factory, a production control panel for informing a worker of the achievement rate of a production target and the like, and an indicator (so-called "so-called" so-called "" Andong ") is installed.
The production control panel displays the current day's production targets, current results, downtime, etc. Also, Andong is supposed to inform the support staff, etc. of the occurrence of an abnormality in each process of the production line and information on whether a substitute is needed.

On the production control panel and ANDON, the size of each display portion is formed to a certain extent so that the operator can visually recognize the display contents from a distance. Further, even in one production line, the displayed contents may be different due to the difference in the position where the production control panel and ANDON are installed. For example, the production control panel installed in the previous process displays the targets and achievements of the previous process, and the production control panel installed in the subsequent process displays the targets and achievements of the subsequent process. The display screen of each production control board can be confirmed by a monitor device provided in a control room or the like, which is remote from the production line. A CRT display device is generally used as the monitor device.

[0005]

The production management information informs the operator of the production target of the day, the current performance, the stop time, etc., and the display screen of the display shows the target, performance,
The stop time etc. is displayed. The characters such as “target” indicating the production target, “actual result” indicating the actual production result, “stop” indicating the cumulative stop time, etc. are always the same, and the numbers indicating the actual result and the stop time change. Therefore, those characters are always displayed at the same position on the display screen of the monitor CRT display device. As a result, the screen of the CRT display device may be burned in, making it difficult to see when displaying another character, or CR
There is a problem that the life of the T display device is shortened. As a screen burn-in prevention method, there is a method of displaying a screen dedicated to burn-in prevention every predetermined time. However, this method has a problem that necessary production control information and the like cannot be displayed while the screen for exclusive use for image sticking prevention is displayed.

The present invention has been made in view of the above problems, and an object thereof is to display a necessary state on a screen of a CRT display device for monitoring the display contents of a display installed in a production line. An object of the present invention is to provide a method for preventing burn-in of the monitor screen of the production control display system, which can surely prevent burn-in of the screen of the CRT display device.

[0007]

In order to achieve the above object, the invention according to claim 1 is provided with at least a display capable of displaying production control information, and a CRT display device for monitoring the display content of the display. In the production control display system, the monitor screen displayed on the screen of the CRT display device is displayed smaller than the size of the screen of the CRT display device, and the display position of the monitor screen is changed every predetermined time.

According to the second aspect of the invention, in the production control display system including at least a display capable of displaying the production control information and the CRT display device for monitoring the display contents of the display, the CRT display device is provided. The monitor screen displayed on the screen is displayed smaller than the screen size of the CRT display device, and the display position of the monitor screen is changed based on the operation information.

[0009]

[Operation] Production management information and the like are displayed on the display provided on the production line. A screen (monitor screen) having the same contents as the display screen of the display is displayed on the CRT display device. The monitor screen is displayed smaller than the screen size of the CRT display device, and the display position of the monitor screen is changed every predetermined time. Therefore, even if the same display is always made at the same position on the display screen of the display, the display position changes on the screen of the CRT display device, and the screen burn-in is prevented.

According to the second aspect of the invention, the display position of the monitor screen is changed based on the operation information. The operation information means an appropriate combination of a target achievement rate, a cumulative stop time, a predetermined time, and the like.

[0011]

【Example】

(Embodiment 1) Hereinafter, a first embodiment in which the present invention is embodied in a production management display system for an automobile assembly line will be described with reference to FIGS.
Follow the instructions below.

As shown in FIG. 1, a production management display system includes a programmable controller 1, a display control personal computer (hereinafter, referred to as a control personal computer) 2,
An operation management personal computer (hereinafter referred to as an operation management personal computer) 3 is connected via a network 4. The control personal computer 2 has a large L as a display.
An ED (light emitting diode) display 5 is connected. The operation management personal computer 3 is equipped with a CRT display device 3a for monitoring and a keyboard 3b as an input device. In addition, the assembly line is roughly divided into three processes of front rigging, suspension, and rear rigging.
The control personal computer 2 is installed for each process (Fig. 1
Then, only one is shown). Each process is composed of a plurality of smaller processes, and a process number is assigned to each process.

The programmable controller 1 is connected to equipment 6 provided in each process of the production line via a signal line, controls each equipment 6, and outputs from an abnormal signal output section provided in each process. An abnormal signal is input. The abnormality signal output section is a push button switch 7 used when an abnormality detector provided in each equipment 6 and a maintenance time indicator, or when a worker needs assistance.
Etc. is a general term for devices that output a signal indicating a state different from the normal operating state.

The programmable controller 1 digitizes (encodes) the input abnormal signal according to its type,
The data is output as a data signal on the network 4 and stored in a storage device (not shown) built in the programmable controller 1. The storage device has a capacity capable of accumulating operation history data of at least one day of the production line, and the operation history data of the production line of the day is sequentially stored. The programmable controller 1 has a built-in timer, and the time at which the abnormality of each process occurs and the time when it is resolved is stored together with the type of abnormality. The programmable controller 1 calculates the operation record and stop time of the production line on the basis of the operation history data stored in the storage device, and outputs it as a data signal of the operation record and stop time on the network 4.

As shown in FIG. 2, the LED display 5
The display unit 8 is a 16 × 16 dot matrix unit 8
a is a plurality of rows and a plurality of columns (12 rows and 12 columns in this embodiment)
It is configured by arranging in. The LEDs used in the dot matrix unit 8a include red and green L
A two color LED with an ED chip in one lamp is used. The two-color LED has a common terminal, one terminal for red lighting, and one terminal for green lighting, and has a total of three terminals. When electricity is applied between the common terminal and the lighting terminal, the corresponding color LED lights. To do. The two-color LED lights up red when only red lights up, lights up green when only green lights up, and lights up orange when both lights up.

A control circuit (not shown) is provided on the back surface of each dot matrix unit 8a. The control circuit includes a Y (row) driver that controls energization to the common terminal of the two-color LED, and an X (column) driver that controls energization to the red lighting terminal or the green lighting terminal. Then, the control circuit sets the two-color LE according to the control signal and the display data signal from the control personal computer 2.
Turn on D.

As shown in FIG. 4, the control personal computer 2 is a CP.
U (central processing unit) 9, ROM (read only memory) 10, RAM (random access memory) 11a as a storage device, non-volatile RAM 11b, display data storage RAM (hereinafter referred to as display RAM) 12, input / output port 13 , A shift register 14 and a driver 15. CPU 9, ROM 10, RAM 11a, non-volatile RAM 11b, display RAM 12, input / output port 13
The shift register 14 is connected via the address bus AB, the data bus DB and the control bus CB, and the CPU 9 and the driver 15 are connected via the control bus CB.
A control program is stored in the ROM 10. RA
The calculation result of the CPU 9 and the like are temporarily stored in M11a. Further, the nonvolatile RAM 11b stores a large number of display pattern formats for displaying on the LED display 5.

Some of the display pattern formats whose main purpose is to display production control information like the conventional production control panel correspond to a display screen as shown in FIG. 5, for example. In this display pattern, the production control information is displayed in the top 10 lines of the 12 lines of the dot matrix unit 8a, and the message is displayed in the bottom 2 lines. In the production control information, all the kanji display parts are fixed display data, and all the numeric display parts are variable display data. Also, the display portion of the message is variable display data.
In this display pattern, a “target” indicating a production target, a “actual result” indicating a production result, a “stop” indicating a cumulative stop time, an “overtime work” indicating a planned overtime time, and their numerical values are displayed large. This display pattern is used when there is no abnormality in the production line, and the current time is displayed on the message display section when there is no particular message to be displayed. Kanji is displayed in green and numbers are displayed in orange. However, the number indicating the cumulative stop time is displayed in orange if the cumulative stop time is within the allowable stop time, but is displayed in red if it exceeds the allowable stop time. Further, the display color of the message is set appropriately.

Further, as a means for displaying ANDON information when an abnormality occurs in the production line, there is a display pattern format corresponding to a display screen as shown in FIG. 6, for example. In this display pattern, production control information is displayed in the upper half of the LED display 5, and ANDON information and messages are displayed in the lower half. The Chinese character portion of the production control information becomes the fixed display data, and the numerical display portion of the production control information and the ANDON information and message display portion become the variable display data. The production management information displays targets, achievements, and stoppages, and overtime is omitted. As the stop time, the cumulative stop time and the stop time due to the abnormal stop at this time are switched and displayed every predetermined time (for example, 30 seconds). When the cumulative stop time is displayed, today's display is also displayed after the stop character.

The display of the ANDON information is performed by displaying the process numbers in which the abnormal signal is output in the order of occurrence of the abnormalities. When the process is not stopped and the supporter is simply called, a black number is displayed with an orange background and a black number is displayed with a red background when the process is stopped. The message display section displays "equipment abnormality" and the type of abnormality.

When it is necessary to display many kinds of messages, another basic display pattern is used in which the size of the characters representing the production control information is reduced and the area of the message display portion is increased. When the number of characters in one message is too large to fit in one line, scrolling display (flowing character display) is performed in which displayed characters move in sequence to new characters.

The CPU 9 is the programmable controller 1
Alternatively, the output signal from the operation management personal computer 3 is input through the input / output port 13. Then, the signal data is stored in the RAM 11a, and an appropriate display pattern format corresponding to the signal is stored in the nonvolatile RAM 11a.
The display pattern is stored in the display RAM 12 by selecting from a number of display pattern formats stored in b.
Further, the display data in the display RAM 12 is rewritten based on the signal data. In the display RAM 12, a storage area having an address corresponding to the arrangement of each two-color LED forming the LED display 5 is separately provided for red display data and green display data.

When displaying on the LED display 5,
The CPU 9 sends the display data stored in the display RAM 12 to the shift register 14 in a predetermined order. The shift register 14 converts the 16-bit parallel data from the display RAM 12 into serial data. The driver 15 outputs the display data signal and the control signal to the LED display 5. The display data is transferred in parallel with respect to the display data corresponding to the 12 rows of dot matrix units 8a forming the LED display 5. The display data corresponding to the uppermost (first stage) two-color LED of the dot matrix unit 8a in each row is transferred in units of 16 bits, and the display data for one stage is transferred first. 1 step (1
When the display data of 6 × 12 = 192 bits) is transferred, the display data of the next stage is sequentially transferred. Then, when the transfer of the display data of the 16th stage is completed, the transfer of the display data from the 1st stage is repeated again. The transfer of data for 16 stages is repeated at a cycle of about 1/100 second.

That is, of the 16 stages of the two-color LEDs forming the dot matrix unit 8a of each row, only one stage is turned on at one time. This operation is almost 1/1
Since it is repeated at a cycle of 00 seconds, even if only one stage is lit at one time, when a person looks at the image, afterimages cause 2
You are seeing the same screen as the screen where the color LEDs are lit at the same time.

As shown in FIG. 3, the operation management personal computer 3 includes a CPU 16, a ROM 17, a RAM 18a and a non-volatile RA.
M18b, display RAM (video RAM) 19, input / output port 20, timer 21, input / output port 22 for CRT
Etc., and signals are transmitted and received via the bus line BL. A display pattern format similar to that stored in the nonvolatile RAM 11b of the control personal computer 2 is stored in the nonvolatile RAM 18b. RAM
The calculation result of the CPU 16 and the like are temporarily stored in 18a. The display RAM 19 has a storage area for three screens of the LED display 5. Then, the operation management personal computer 3 causes the CRT display device 3a to display the same display as that of each LED display 5 based on the output signal from the programmable controller 1.

The CRT display device 3a is a 14-inch CRT.
The display screen of the LED display 5 is formed in a size having the number of pixels capable of displaying three at a time. That is, the number of pixels of the LED display 5 is 1
The number of pixels of a CRT display device is approximately 640 × 400 on a 14-inch screen, while the pixel size is 92 × 192. Therefore, a 14-inch CRT display device can display three display screens of the LED display 5 at one time.

The operation management personal computer 3 can access the programmable controller 1 or the control personal computer 2 via the network 4. Then, the RAM 1 in the control personal computer 2 according to the signal from the operation management personal computer 3
The data in 1a, the non-volatile RAM 11b and the display RAM 12 can be rewritten. Rewriting of the data in the display RAM 12 is normally the target numerical value and the message on the message display unit today. When rewriting, operate the operation management PC 3 and the operator
LED display 5 on the display screen of RT display device 3a
A display screen desired to be displayed is created and the display data is output to the control personal computer 2 via the network 4.

Next, the operation of the production management display system configured as described above will be described. The system is powered on prior to the production line operation. Control PC 2 is R
Operates according to the control program stored in the OM10,
When the power is turned on, the initialization process is first performed. Next, the display pattern format in which the production control information is displayed in large size is selected, and the data is stored in the display RAM 12. Then, the display data stored in the display RAM 12 is sequentially output to the LED display 5 as a display data signal together with the control signal. The display data signal and the control signal are received by the receiver (not shown) of the LED display 5 and sent to the control circuit of the dot matrix unit 8a via the buffer and the decoder.

Then, a standard screen as shown in FIG. 5 is displayed on the LED display 5. However, at this time, the numerical value indicating the production management information, which is the variable display portion, is not displayed. Further, the message display section displays time. Next, the display data signal of the target number of today, which is one of the variable display data, is input from the operation management personal computer 3 to the control personal computer 2, and the display RAM 1 is based on the display data signal.
The data in the two corresponding areas is rewritten. Therefore,
After that, the display data output to the LED display 5 includes effective variable display data indicating the target number for today, and the numerical value is displayed on the LED display 5.

When the operation of the production line is started next, the programmable controller 1 inputs signals from the equipment 6 and the push button switch 7 of each process. Then, the operation status of the production line is judged according to the presence / absence of an abnormal signal, the abnormal signal is converted into data (encoded) according to its type, and the data is stored in the built-in storage device as operation history data. . The programmable controller 1 converts all the input abnormality signals into data and stores it in the storage device as operation history data. That is, the operation history data of the production line of the day is sequentially stored in the storage device. Further, the programmable controller 1 outputs the data-generated abnormal data as a data signal on the network 4.

The programmable controller 1 calculates the operation record and stop time of the production line on the basis of the operation history data stored in the storage device, and outputs it on the network 4 as a data signal of the operation record and stop time. The control personal computer 2 inputs the data signal and outputs the signal data to the R
The variable display data corresponding to the operation results and the stop time of the display RAM 12 is rewritten based on the data stored in the AM 11a. Then, the value is displayed on the LED display 5. That is, when there is no abnormality in the production line, the LED display 5 displays the standard screen as shown in FIG. 5 in which the production management information is largely displayed.

The overtime hours are manually input to the control personal computer 2, the display data corresponding to the overtime hours display portion of the display RAM 12 is rewritten based on the data, and the overtime hours are displayed on the LED display 5. However,
The operation management personal computer 3 accesses the programmable controller 1, and the production target and programmable controller 1
The overtime hours may be calculated from the operation history data and the like accumulated in the storage device, and a data signal for displaying the overtime hours may be output.

When the abnormal signal data output from the programmable controller 1 is input to the control personal computer 2, L
As the display pattern format to be displayed on the ED display 5, for example, a display pattern format corresponding to the abnormal display screen as shown in FIG. 6 is selected. Next, after storing the data in the display RAM 12, the variable display data corresponding to the ANDON information display section and the message display section are rewritten based on the abnormal signal data. After that, the display data of the display RAM 12 is displayed in the same manner as described above by the LED.
It is output to the display 5, and the LED display 5 displays an abnormality display screen as shown in FIG. When the abnormality in the production line is resolved, the LED display 5
The screen of etc. returns to the standard screen again.

Next, the screen display on the CRT display device 3a will be described. As shown in FIG. 7, on the CRT display device 3a, three monitor screens V1, V2, V3 having the same display contents as the screens displayed on the respective LED displays 5 are arranged side by side in the same size. The status is displayed. And
At the upper part of each screen V1, V2, V3, characters representing the corresponding process such as "front rigging" are displayed. Three screens V1, V2, V3
Are always displayed side by side, but they are not always displayed at the same position, but are initially displayed at the top of the screen of the CRT display device 3a as shown in FIG. Then, the display position is changed downward at regular intervals, and when the display position reaches the lowermost portion, the display position is changed again to the uppermost portion, and then the display position is sequentially changed downward again.

The CPU 16 of the operation management personal computer 3 operates according to the flowchart of FIG. 8 to change the display positions (drawing positions) of the screens V1, V2 and V3. That is, CPU1
Reference numeral 6 reads the time stored in the RAM 18a based on the signal of the timer 21 and determines whether it is the display position change time. If the time is not the display position change time, screen V1,
The display position of V2, V3 is not changed, and each screen V1, V2, V3
Is displayed in the same position as before. If the time is the display position change time, the CPU 16 determines each screen V corresponding to the time.
Set the display position of 1, V2, V3. Then, thereafter, the respective screens V1, V2, V3 are displayed at the set positions until the next display position change time comes. It is not necessary to change the display position of each screen V1, V2, V3 frequently, and each screen V1, V2, V3
May be moved from the top to the bottom of the screen of the CRT display device 3a several times a day.

When there is no abnormality in each process, the LED display 5 displays a standard screen as shown in FIG.
On this display screen, the Kanji for goals, achievements, stoppages, overtime, etc. and the figures for today's goals, which are displayed outside the message display, do not change. Therefore, unless the display positions of the monitor screens V1, V2, V3 displayed on the CRT display device 3a change, the same characters are displayed at the same position on the CRT display device 3a for a long time, and the screen burn-in occurs. Occurs. However, as described above, each screen V for monitor is displayed on the CRT display device 3a.
Since the display positions of 1, V2 and V3 are changed every predetermined time,
Even if the display content does not change, screen burn can be reliably prevented. As a result, the life of the CRT display device 3a is extended, and it is possible to avoid the situation where the display is difficult to see when the display pattern format of the screen is changed.

(Second Embodiment) Next, a second embodiment will be described with reference to FIG. In this embodiment, the method of changing the display position of each of the monitor screens V1, V2, V3 displayed on the CRT display device 3a is different from that of the previous embodiment. In the above-described embodiment, the only criterion for changing the display position is the time, and each screen V1, V2, V3
Are always displayed in a row. However, in this embodiment, not only the time but also the target achievement rate and the cumulative stop time are taken into consideration in the criterion for changing the display position, and each screen V1, V2,
The point that V3 is not always displayed in one horizontal row is greatly different from the above embodiment.

At the start of operation of the production line, each screen V1,
V2 and V3 are displayed in a state of being aligned in one horizontal line at approximately the center of the CRT display device 3a. Then, the CPU 16 of the operation management personal computer 3 operates according to the flowchart of FIG.
The display positions (drawing positions) of the screens V1, V2, V3 are changed.
That is, the CPU 16 determines the R based on the signal of the timer 21.
The time stored in the AM 18a is read to determine whether it is the display position change time. If the time is not the display position change time, the display positions of the screens V1, V2, V3 are not changed,
Each screen V1, V2, V3 is displayed at the same position as before. If the time is the display position change time, the CPU 16 calculates the target achievement rate and confirms the cumulative stop time up to the time for each of the "front outfitting", "foot suspension", and "rear outfitting" steps. Next, the display position of each screen V1, V2, V3 is set according to the target achievement rate of each process and the cumulative stop time. In principle, the display position is changed to the upper side, and the movement amount is set based on the predetermined target achievement rate. If the target achievement rate is 100%, the movement amount is set to a predetermined reference amount, and if the target achievement rate is other than 100%, the movement amount is increased or decreased from the reference amount according to the ratio. Further, when the cumulative stop time is equal to or longer than the predetermined time, the movement amount of the display position is negative, that is, the display position of the screen is changed to the lower side. After completing the setting of the display position of each screen V1, V2, V3, the CPU 16
Display 2, V3 at the set position. Therefore, similarly to the above-described embodiment, the image sticking on the screen of the CRT display device 3a is surely prevented.

Further, in this embodiment, the display position of each screen V1, V2, V3 is changed in consideration of the target achievement rate of each process and the cumulative stop time, so that the administrator can use the CRT display device 3a.
The rough operating condition of each process can be judged by the position of each screen V1, V2, V3 displayed on the screen.

The present invention is not limited to the above-mentioned embodiment. For example, as a method for setting the timing of changing the display position of each screen V1, V2, V3, instead of the structure for reading the time, the previous display The time elapsed from the position change timing may be counted by the timer 21 and the display position may be changed after a predetermined time has elapsed. Further, in the first embodiment, the display position is changed so as to move each screen V1, V2, V3 from the bottom to the top, or instead of gradually moving the display position, the upper, center, and lower three screens are displayed. You may move to a position in order.

Further, in the above embodiment, the display screens of the three LED displays 5 are simultaneously displayed on the CRT display device 3a, but the LED display 5 installed on the production line is also shown.
If there are two or one, the corresponding number of monitor screens will be two or one.

The number of dot matrix units 8a constituting the LED display 5 may be other than 12 rows and 12 columns, or 16 dot matrix units 8a may be provided.
Other than the x16 dot matrix may be used. Further, LEDs other than the two-color LEDs of red and green may be used, or the display may be replaced by an LED display and a display of another system such as a plasma display or a liquid crystal display may be used. or,
Even if display data for displaying the same screen as the LED display 5 on the CRT display device 3a is transferred from the display RAM 12 of the control personal computer 2 to the operation management personal computer 3 and the operation management personal computer 3 uses the display data. Good. Further, only the production control information or the production control information and a message may be displayed on the LED display 5 and an ANDON may be provided separately, or an operation control personal computer may be provided in a control office in a building different from the production line.

[0043]

As described above in detail, according to the present invention, even if the same display is always made at the same position on the display screen of the display for displaying the production control information, it is displayed on the screen of the CRT display device for monitoring the display content of the display. Since the display position changes, CR is performed while maintaining the necessary display.
It is possible to reliably prevent burn-in of the screen of the T display device.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a production management display system according to a first embodiment of the present invention.

FIG. 2 is a schematic front view of an LED display.

FIG. 3 is a block circuit diagram showing a configuration of an operation management personal computer.

FIG. 4 is a block circuit diagram showing a configuration of a control personal computer.

FIG. 5 is a schematic diagram showing an example of a standard screen displayed on an LED display.

FIG. 6 is a schematic diagram showing an example of an abnormality display screen displayed on an LED display.

FIG. 7 is a schematic diagram showing a state in which a monitor screen is displayed on a CRT display device.

FIG. 8 is a flowchart showing the operation of the CPU of the operation management personal computer when setting the monitor screen display position.

FIG. 9 is a flowchart showing the operation of the CPU of the operation management personal computer when setting the monitor screen display position in the second embodiment.

[Explanation of symbols]

1 ... programmable controller, 2 ... control personal computer,
3 ... Operation management personal computer, 3a ... CRT display device, 5 ... LED display as display, 6 ... Equipment, 8
a ... Dot matrix unit, V1, V2, V3 ... Monitor screen.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Noritsugu Ishida 2-chome, Toyota-cho, Kariya city, Aichi Prefecture Toyota Industries Corp.

Claims (2)

[Claims] 1. A production control display system including at least a display capable of displaying production control information and a CRT display device for monitoring the display contents of the display, wherein a monitor screen displayed on the screen of the CRT display device is displayed by CRT. A method for preventing image sticking on a monitor screen of a production control display system, in which the size of the screen of the device is displayed smaller and the display position of the monitor screen is changed every predetermined time. 2. A production control display system including at least a display capable of displaying production control information and a CRT display device for monitoring the display contents of the display, wherein a monitor screen displayed on the screen of the CRT display device is displayed by CRT. A method for preventing image sticking on the monitor screen of the production control display system, which is displayed smaller than the screen size of the device and the display position of the monitor screen is changed based on the operation information.