JPH039472B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus equipped with a dynamic display.

<Prior Art> There have been remarkable advances in electronic technology in recent years. In particular, the integration of electrical and electronic circuits has progressed, and high-performance microcomputers have appeared to control various devices. In this specification, an electronic copying apparatus using a microcomputer will be particularly described.

FIG. 1 is a sectional view of a copying apparatus to which the present invention can be applied.

The surface of the drum 11 is made of a three-layer photoreceptor using a CdS photoconductor, is rotatably supported on a shaft 12, and starts rotating in the direction of an arrow 13 in response to a copy command.

When the drum 11 rotates to the normal position, the document placed on the document table glass 14 is illuminated by an illumination lamp 16 that is integrated with the first scanning mirror 15, and the reflected light is used for the first scanning. Mirror 15 and second
It is scanned by a scanning mirror 17. First scanning mirror 1
5 and the second scanning mirror 17 move at a speed ratio of 1:1/2, so that the document is scanned while the optical path length in front of the lens 18 is always kept constant.

The above reflected light image shows the lens 18 and the third mirror 19.
After passing through the fourth mirror 20, an image is formed on the drum 11 at the exposure section 21.

After the drum 11 is charged (for example, +) by a primary charger 22, an image irradiated by an illumination lamp 16 is slit-exposed in the exposure section 21.

At the same time AC or primary and opposite polarity (e.g. -)
The static electricity of the drum 11 is removed by the static eliminator 23, and then the drum 11 is exposed to light from the entire surface exposure lamp 24.
Forms a high contrast electrostatic latent image on top. The electrostatic latent image on the photosensitive drum 11 is then visualized as a toner image by the developing device 25.

The transfer paper 27-1 or 27-2 in the cassette 26-1 or 26-2 is transferred to the paper feed roller 28.
-1 or 28-2, the rough timing is taken by the first register roller 29-1 or 29-2, and the second register roller 30
The photosensitive drum 11 is sent out in the direction of the photosensitive drum 11 with accurate timing.

Next, while the transfer paper 27 passes between the transfer charger 31 and the drum 11, the toner image on the drum 11 is transferred onto the transfer paper.

After the transfer is completed, the transfer paper is guided to the conveyor belt 32 and further to a pair of fixing rollers 33-1, 33-2, where it is fixed by pressure and heat, and then discharged onto the tray 34.

After the transfer, the surface of the drum 11 is cleaned by a cleaning device 35 composed of an elastic blade, and the process proceeds to the next cycle.

In addition, in order to control the above image forming cycle at each point in time, a drum clock pulse DCK is generated by a sensor 11b that optically detects the clock point of a clock board 11a that rotates with the rotation of the drum 11.

Next, a conventional control device using a microcomputer as a control device for the above-mentioned electronic copying apparatus will be described below.

FIG. 2 shows a control system of a conventional copying machine using a microcomputer, FIG. 3 shows a display switching subroutine, and FIG. 4 shows output timing waveforms of output terminals R1 to R4, which will be described later.
FIG. 5 shows an operating procedure when the microcomputer performs parallel operations of reading and displaying the drum clock during a copying operation, and this procedure is stored in a memory (not shown) in the microcomputer MCO.

In Figure 2, MCO is a one-chip microcomputer, KM is a key input matrix, SET1, SET2, COPY1, COPY2 are 7-segment displays consisting of light emitting diodes, liquid crystals, etc., and SET1 is a set value for the number of copies. SET2 is a display that displays the second digit of the set value for the number of copies, COPY
1 is a display that displays the first digit of a copy counter indicating how many copies have been completed at that time, and COPY2 is a display that displays the second digit of the copy counter. The R port is an output port that can be set and reset discretely.
When 1 is set, that is, a digital “1” signal is output to R1, the COPY2 indicator lights up.
Corresponding key input matrix KM key “0”
When "1", "2", and "3" are pressed, a key read signal is input to the K port, which will be described later. Which key was pressed is determined by which port of the K port the input was made to. Similarly, R2, R3, and R4 each have an indicator.
COPY1, SET2, and SET1 are displayed by lighting, and a key read signal is input to the K port, which will be described later. R5 is an output terminal which outputs a signal to turn on a jam indicator lamp when a jam occurs in the copying machine, and R6 is set after optical scanning of the original is completed and outputs an optical system backward movement signal. R7 is an output terminal that is set at the start of optical scanning of a document and outputs an optical system advance signal and an exposure lamp lighting signal, and R8 is an output terminal that outputs an optical system advance signal and an exposure lamp lighting signal. When the paper feed signal output terminal R8 is set, the paper feed solenoid is activated, the paper feed roll 28 is lowered, and paper is fed. R9 is an output terminal that is set when the power is turned on to operate the main motor and high voltage transformer. The K port is an input port that can discretely check input and reads key input. The X port is also an input port that can be used to check the input on a daily basis, and the X1 terminal receives the signal OHM when the optical system reaches the home position, and the X2 terminal receives a clock pulse synchronized with the rotation of the drum. The S port is an output terminal that outputs 4 bits in parallel.Set 1 digit, Set 2 digit, Copy 1 digit,
The 2-digit copy data is output to the display decoder DD, and the SET decoder DD converts the data to a 7-bit signal and outputs the data to the display devices SET1, SET2, COPY1,
This is what is displayed on COPY2.

FIG. 3 shows the display switching subroutine. A detailed explanation of each step of the display switching subroutine will be omitted. Each time the display switching subroutine is used, the outputs of R1 to R4 are sequentially set, the display is dynamically lit, and a key is read into the input port K from the key input matrix KM corresponding to the R output.
Therefore, while copying is normally stopped, it is sufficient to repeat the display of the copy counter and the sensing of key inputs, so that the output timing waveforms of R1 to R4 have a constant duty ratio as shown on the left side of FIG. 4.

On the other hand, once the copy operation starts, there is no need to read the keys, but the display must be lit dynamically at all times. Additionally, drum clock pulses generated mechanically, magnetically, or optically to track the operating position of the machine.
DCK must be read through terminal X2 and the number of pulses must be counted in parallel. FIG. 5 shows a flowchart of this operation. loop
Loop a indicates a "1" level section of the waveform of the drum clock pulse DCK in FIG. 6, and loop b indicates a "0" level section of the drum clock pulse DCK waveform.

In the flowchart shown in Figure 5, in STEP _5-1 , it is determined whether " ₁ " is set at the drum clock pulse DCK input terminal
At the falling edge of the pulse DCK, proceed to STEP5-2, again judge whether 1 is set at the terminal X ₂ , _and
If = 0, the display switching subroutine is executed, and STEP 5 is executed at the rising edge of the drum clock pulse DCK.
-Proceed to 3. In STEP5-3, 1 is subtracted from the data at the memory address _A1 where the first digit of the preset number of pulses to be counted is stored, and the result is stored in the memory address _A1 . Here, the number of pulses to be counted is stored in hexadecimal notation at memory address A ₁ and memory addresses A ₂ and A ₃ to be described later. next
In STEP 5-4, it is determined whether the contents of the memory address A ₁ have become 15, and if A ₁ is not 15, then
Return to STEP 5-1. Continue counting and when A ₁ = 15, proceed to STEP 5-5 and store the memory address where the second digit of the preset number of pulses to be counted is stored.
A minus 1 from the data of ₂ and the memory address
Store in A ₂ . In STEP5-6, it is determined whether A ₂ =15, and if A ₂ =15, the process returns to STEP5-1. Below is the preset number of pulses to be counted.
The same judgment is repeated for the memory address A ₃ where the digit is stored, and the memory addresses A ₁ , A ₂ ,
Counting ends when all the data in A ₃ becomes 15,
When R6 is turned on, the optical system reverse signal is output.

Therefore, if the clock pulse DCK rises after resetting R1 and setting R2 in the display switching subroutine in loop b, after counting A ₁ =
Unless it becomes 15, go through loop 1 again
Returning to STEP5-1, the display switching subroutine is then entered to reset R2 and set R3. Since the time required for one operation command in the flowchart of a microcomputer is constant,
The duty ratio of the outputs from output terminals R1 and R2 will be wide, for example as shown on the right side of Figure 4, so the display time of COPY2 and COPY1 will also be significantly reduced and the display will flicker. It will appear.

Further, conventionally, a dedicated input structure was provided only for the stop key that can be used for input at all times, and data input keys such as a numeric keypad and the stop key were input from separate input structures, making the structure of the key input section complicated.

<Objective> The object of the present invention is to provide an image forming apparatus that eliminates the above-mentioned drawbacks. More specifically, when the dynamic display is controlled by a control means using a program, the duty ratio of the dynamic display is kept approximately constant by sequentially and repeatedly outputting a scanning signal for each display digit of the dynamic display. By doing so, flickering of the display can be eliminated, and furthermore, the data input key and the stop key can be input using the same input configuration in which key input is performed using scanning signals that are sequentially and repeatedly output as described above, and the key input configuration can be simplified. Moreover, during the image formation period, key input of the data input key is disabled on the condition that image formation is in progress, and the period during which the data input key and stop key can be accepted can be changed even though the key input configuration is the same. It is an object of the present invention to provide an image forming apparatus which can perform different key inputs by using the scanning signals and which can reliably perform key input by using the above-mentioned scanning signals.

<Embodiment> The control device of the present invention will be explained below with reference to the drawings.
FIG. 7 is a control circuit diagram when the present invention is applied to an electronic copying apparatus. In Figure 7, MC1 is a one-chip microcomputer for real-time control, MC
2 is a one-chip microcomputer for sequential control, KM' is a key input matrix similar to KM in Fig. 2, DD' is a display decoder similar to Fig. 2,
COPY2', COPY1', SET2', SET1' are the same indicators as COPY2, COPY1, SET2, SET1 in Figure 2, and K11 to K14 are K1 to K in Figure 2.
Input terminals similar to 4, S11 to S14 are S in Fig. 2
1 to S4, R12 to R15 are the same output terminals as R1 to R4 in FIG. 2, and R11 is a command signal from the microcomputer MC1 to the microcomputer MC2.
When R11 is "1", it means the start of copying and connection, and when it is "0", it means to end copying and after the drum and optical system return to the home position, reset the main motor operating terminal R12, which will be described later. , and copying prohibited. X11 is the drum clock pulse DCK input terminal, X12
is an input terminal from the output terminal R25 of MC2 (described later), X13 is an input terminal from the output terminal R24 of MC2 (described later), X14 is an input terminal from R23 as well, Y11 is an input terminal from R22, and Y12 is an input terminal from R22.
Y14 is an input terminal for an external signal (hereinafter referred to as a sequence check signal) for causing the microcomputer MC1 to monitor the operation of the microcomputer MC2 (hereinafter referred to as a sequence check).
is an input terminal for an external sequence check start signal to command the start of a sequence check, X21 is an input terminal from the output terminal R11, K21 is an input terminal for the drum clock pulse DCK, and K22 is an optical system home input terminal. Position signal input terminal, K23 and K24 are cassette size detection signal input terminals, R21 is driver circuit DR1
When R21 is "1", the high voltage transformer and main motor are in the operating state;
When R21 is "0", the high voltage transformer and the main motor are in a stopped state, and the signal from R21 is connected to the input terminal Y12. R22 is a signal output terminal for activating the paper feed solenoid via the driver circuit DR2, and the signal from R22 is connected to the input terminal Y11. R23 is a signal output terminal for driving the optical system drive circuit through the driver circuit DO3 to advance the optical system and lighting the document exposure lamp, and the signal from R23 is input to the input terminal X14. R24 is a signal output terminal for driving the optical system drive circuit to advance the optical system via the driver circuit DR4, and the signal from R24 is input to the input terminal X13. R25
is an input terminal for a signal for lighting the jam indicator lamp via the driver circuit DR5, and the signal from R25 is input to the input terminal X12.

Control procedures stored in a memory (not shown) in the microcomputer MC1 are shown in FIGS. 8 to 10. The control procedure will be explained below.

First, a step-by-step explanation will be given of the control procedure of the microcomputer MC1 when copying is stopped and not during a sequence check. The numbers in □ in FIGS. 8 to 10 correspond to the numbers after STEP used below. When the power is turned on, it is determined in STEP 1 whether a sequence check is being performed or not, and since a sequence check is not in progress, the process proceeds to STEP 2, where the copy 2-digit data is output to the S port, and in STEP 3, R12 is set and the copy 2-digit display is displayed. Set COPY2' to display state. In STEP 4, check Y1 whether copying is in progress or not.
It is determined whether 2 is "1" or "0". Since copying is not in progress here, proceed to STEP 5 and copy K port K1.
1, K12, K13, and K14 are read.
In STEP 6, determine whether the "1" level is set at one of the above K ports, and if the "1" level is set, determine whether the key-in has already been performed in STEP 7, and if the key-in has not already been completed. Key “0” “1” “2” from STEP8 to STEP15
Enter the data "3" into a 1-digit register (not shown). Also, if there is no key-in in STEP 6,
Proceed to STEP16, reset R2, copy 1-digit data to S port in STEP17, and reset R3.
Set in STEP 18. From STEP19 to STEP30, keys "4", "5", "6", and "7" are read in the same manner as from STEP4 to STEP15 described above.
In STEP31, reset R3, then in STEP32, output the set 2-digit data to the S port, and then in STEP33
Set R4 with . In STEP 34, determine whether copying is in progress, and since copying is not in progress, press K in STEP 35.
Read the port. In STEP36, determine whether there is a key-in or not, and if there is a key-in
In STEP 37, determine whether a key has already been pressed, and if not, determine which key was pressed. For clear key, microcomputer MC1
Set 1 digit stored in a register (not shown) of
Clear the set 2 digit, copy 1 digit, and copy 2 digit data (STEP 38, STEP 45), set R11 for the copy key (STEP 39, STEP 44),
In the case of 8 keys or 9 keys, the 1-digit set data is transferred to the 2-digit set register, and the data of 8 or 9 is transferred to the 1-digit set register (STEP 40 to 43). next
In STEP 46, reset R14, output the SET 1-digit data to the S port (STEP 47), set R15, display SET1 on the display, and read the stop key of the key input matrix KM' (STEP 49). In the case of R1
1 (STEP 50). If the stop key has not been pressed, repeat no operation (NOP) twice and then reset R15 (STEP 51).
Next, determine whether copying is in progress (STEP 52) and return to STEP 2 since copying is not in progress. Let's follow step by step the display switching while copying is stopped as described above. However, it is assumed that the key is not turned in.

STEP2→STEP3 (R12 set)→STEP4→
STEP5→STEP6→STEP16 (R12 reset)→
STEP17→STEP18 (R13 set)→STEP19→
STEP20→STEP21→STEP31 (R13 reset)
→STEP32→STEP33 (R14 set)→STEP34
→STEP35→STEP36→STEP46 (R14 reset)→STEP47→STEP48 (R15 reset)→
STEP49→STEP111→STEP112→STEP51 (R1
5 reset)→STEP52→STEP2 operations are repeated. Output terminal R12, R in such a case
The output time chart of 13, R14, and R15 is shown in FIG. As shown by the solid line in FIG. 11, the output voltages of the terminals R12, R13, and R14 are output with the same duty ratio, so the terminal R1
2. Display corresponding to R13, R14, R15
COPY2, COPY1, SET2, and SET1 light up at the same duty ratio, so the display does not flicker.

Next, the control means during the copying operation will be explained step by step. After turning on the power, STEP1
Determine whether it is a sequence check or not. Since it is not a sequence check, proceed to STEP 2 and output the copied 2-digit data to the S port. In STEP 3, output the 2-digit data to the S port.
and determine whether copying is in progress in STEP 4. Since copying is not in progress, in STEP105 and STEP106
Perform NOP and reset R12 in STEP16.
In STEP17, output the copy 1-digit data to the S port, and in STEP18, set R13. It is determined again in STEP 19 whether copying is in progress, NOP is performed in STEP 107 and 108, and R13 is reset in STEP 31. STEP32
Outputs the set 2-digit data to the S port,
Set R14 in STEP33. Determine whether copying is in progress again in STEP 34 and repeat NOP twice (STEP 109, 110), then reset R14 in STEP 46, output the set 1-digit data to the S port in STEP 47, and set R15 in STEP 48.
In STEP 49, it is determined whether the stop key has been pressed, and if the stop key has been pressed, R11 is reset (STEP 50). If the stop key is not pressed, repeat NOP twice (STEP 111, 112)
Among them, reset R15 in STEP51,
In STEP52, it is determined whether copying is in progress, and in STEP53, it is determined whether the signal at the optical system advance signal input terminal X14 has become "0". If the advance signal is "1", the process returns to STEP2. If the advance signal is “0”, copy 2-digit data and copy 1 in STEP54.
Add 1 to the copy counter data consisting of digit data and then judge whether the copy counter data and the copy data consisting of copy 2 digit and copy 1 digit data are equal (STEP 55), and if they are equal, Reset R11 to stop the copy operation. If they are not equal, return to STEP 2. Let's follow each step of the display switching during the copy operation as described above. However, it is assumed that the stop key is not pressed and that the optical system reversal signal is not required. STEP2→
STEP3 (R12 set) → STEP4 → STEP105 →
STEP106→STEP16 (Reset R12)→
STEP17 → STEP18 (Set R13) → STEP19
→STEP107→STEP108→STEP31 (Reset R13) →STEP32→STEP33 (Set R14)
→STEP34→STEP109→STEP110→STEP46(R
14) → STEP47 → STEP48 (R15
)→STEP49→STEP111→STEP112→
STEP51 (Reset R15) → STEP52 →
The operation from STEP53 to STEP2 is repeated. In such a case, the output terminals R12, R13, R14,
The output time chart of R15 is almost the same as the time chart during copy stop shown in FIG. 11, and differs only in the portion shown by the dotted line. In other words, the indicators COPY2', COPY1', SET2', SET corresponding to the terminals R12, R13, R14, R15
1' is lit at the same duty ratio, so the display does not flicker. As explained earlier, one
In the case of a system configured with a single chip microcomputer, it was difficult to keep the duty ratio constant because the display switching was done in parallel with the counting of the drum clock DCK. In the , display switching is done by one one-chip microcomputer, and the clock DCK counting is done by another microcomputer, making it possible to eliminate display flickering during copying operations.

Furthermore, in the embodiment, the control signals output from the output terminals R21 to R25 of the microcomputer MC2 are supplied to external loads via the driver circuits DR1 to DR5, and the signals are sent to the X13 of the microcomputer MC1 via the driver circuits. ,X14,Y11,
It has been entered in Y12. By monitoring the movement of this input signal, it is possible to check the system related to the microcomputer MC2.
However, since it is not necessary to perform the sequence check all the time, it is performed only when an external person such as a service person wishes to do so. A sequence check signal is applied to input terminal Y13, and a sequence check is started when a sequence check start signal is input to input terminal Y14.

Also, during the sequence check, the key is not read and the display is not lit, and only if a malfunction is discovered.
The display COPY1' that originally displays the number of copies,
For the convenience of service personnel, etc., the failure load number on COPY 2' is displayed on the displays STE1' and SET2', which normally display the number of sheets set, with the timing of the failure being numbered.

Also, measure the time of one pulse of the drum clock pulse DCK to determine drum eccentricity or pulse DCK.
It is now possible to detect and display any abnormalities.

The operation during sequence check will be explained. Figure 10 shows the microcontroller during sequence check.
A control procedure stored in a memory (not shown) in MC1 is shown, and FIG. 12 shows a timing chart of microcomputer MC2. In the following, it is assumed that the number of drum clock pulses corresponds to the drum rotation angle. After inputting the sequence check signal to Y13 and turning on the power, the process advances from STEP1 to STEP57. In STEP57, the process waits until the sequence check start signal is input, and when the start signal is input, the process advances to STEP58, where R11 is set and a copy start signal is transmitted to the microcomputer MC2. Next, the rise of the drum clock DCK read terminal X11 is detected (STEP59 to STEP60). In STEP61 and 62, in order to measure the time when the drum clock is at the "1" level, the microcomputer counts the number of times the loop passes through the loop formed in STEP61 and 62.
The number of passes is stored in a memory 1 (not shown) in the MC 1. When the drum clock starts up, STEP 63
The process proceeds to step 1, and compares the number of passes stored in the memory 1 with a set number of times indicating the "1" level time of a standard drum clock, and if the number of passes is less than the set number of times, that is, the drum clock If the frequency is abnormal, proceed to STEP77.
In STEP77, COPY “a” into the 2-digit register,
“2” to COPY1-digit register, “0” to SET1
Place in digit and 2-digit registers. after that
In STEP78, reset R11 to cancel the copy operation, and in STEP79 to STEP90, output terminal R1
2, R13, R14, and R15 are set and reset in sequence, and the display shows “〓”, “2”, “0”, and “0”.
The display in SET2', SET1', COPY2', and COPY1' is repeated. That is, it is possible to notify a service person or the like that the drum clock frequency is abnormal.

In addition, although only an abnormality in the drum clock frequency was detected here, even if there is no abnormality in the control signals output from the microcomputer MC2, such as the paper feed solenoid signal or the optical system advance signal, which will be described later, the paper feed solenoid or the optical system itself will operate. If there is an abnormality in the paper feed solenoid or optical system drive unit, the abnormal condition can be displayed on the display in the same way as in the case of an abnormality in the drum clock frequency. It is. That is, the copying apparatus of this embodiment has a control section for checking the operating status of each part of the copying apparatus.

If there is no abnormality in the drum clock frequency,
Proceed to STEP 64 after STEP 63. After the drum clock has been counted 274 times in STEP 64, that is, the drum has rotated 274 degrees, it is determined in STEP 65 whether "1" is set at the paper feed solenoid signal input terminal Y11.
That is, it is determined whether or not a paper feed signal is output at the paper feed start time T2. If "1" is not set at the terminal Y11, in STEP 68, "0" is put into the set 2-digit register, and "3" is put into the set 1-digit register. STEP 69 copies “b” into a 2-digit register, copies “2” into a 1-digit register, and then
Proceed to STEP78, reset terminal R11 to stop the copy operation, and repeat the operation of displaying "b", "2", "0", "2" on the display in a loop consisting of STEP79 and STEP90. . That is, "b",
"2", "0", and "2" indicate that the paper feed solenoid signal is abnormal at the time of starting paper feeding.

If there is no abnormality in the paper feed solenoid signal when paper feeding starts, proceed to STEP 66 and set the drum clock DCK.
54, and again it is determined whether "1" is set at the terminal Y11. In other words, it is determined whether or not the paper feed solenoid signal is output at the paper feeding end point T3. If "1" is set in Y11 at this point, in STEP76, set "0" to the 2-digit register and "4" to the 1-digit register, then proceed to STEP69 and set "b" as described above. Copy 2
Copy “2” to the digit register, put it into the 1 digit register, stop the copy operation in STEP 78, and execute STEP 79.
~ In STEP90, the operation of displaying "b", "2", "0", and "4" on the display is repeated. That is, "b",
"2", "0", and "4" indicate that the paper feed solenoid signal is abnormal at the end of paper feeding.

Next, if there is no abnormality in the paper feed solenoid signal,
After proceeding to STEP 71 and counting the drum clock DCK to 91, it is determined in STEP 72 whether "1" is set at the optical system advance signal input signal X terminal 14 or not. That is, it is checked whether the optical system advance signal is being output at the optical system advance start time T4. If "1" is not set at the terminal X14 at this point,
Set “0” to the 2-digit register in STEP73,
Put “5” in the SET 1-digit register and STEP74
Copy "b" into the 2-digit register and copy "3" into the 1-digit register. Then the above
Perform STEP78 to STEP90, and display “b” on the display.
Displays “3”, “0”, and “5”. That is, "b",
"3", "0", and "5" indicate that the optical system advance signal is abnormal at the time when the optical system advances.

If there is no abnormality in the optical system advance signal at the optical system advance start time T4, proceed to STEP 75 and judge whether the level of the sequence check start signal is "1", and if it is "1", continue the sequence check. , in the case of "0", reset terminal R11 to prevent the next copying operation, proceed to STEP 91, count the number of drum clocks to 200, that is, after the drum has rotated 200 degrees, and then proceed to STEP 92. It is determined whether "1" is set at the forward signal input terminal X14. In other words,
At time T5, the voltage level of the optical system advance signal is “0”
Determine whether it is. If "1" is set at the terminal
Copy “b” to the 2-digit register and copy “3” to the 1-digit register in STEP 74, then write “b”, “3”, “0” on the display in STEP 78 to STEP 90. ”, “6” are displayed. That is, "b", "3", "0", and "6" indicate that the optical system advance signal is abnormal at the time of optical system reversal.

If there is no abnormality in the optical system forward signal, it is determined whether "1" is set at the optical system backward signal input terminal X13 at the same time. That is, at time T5, it is determined whether the voltage level of the optical system backward movement signal has reached the "1" level (STEP 94). Said terminal X1
If “1” is not set in 3, set “6” to the 2-digit register and set it to “0” in STEP95.
Copy “b” to the 2-digit register and copy “4” to the 1-digit register in STEP 96. After that, in STEP 78, reset R11 to complete the copy operation, and then in STEP 79~
In STEP90, “b”, “4”, “0”,
Perform the operation to display “6”. In other words, “b”,
"4", "0", and "6" indicate that the optical system backward movement signal is abnormal at the time when the optical system is reversed.

If the optical system reverse signal is not abnormal at the time of optical system reversal, after counting the drum clock 120 times in STEP97,
In STEP98, the voltage level of the terminal X13 is determined again. In other words, at the time chart in Figure 11
At _T6 , it is determined whether the voltage level of the optical system backward movement signal has reached the "0" level. Said terminal X1
If the "1" level has reached 3, set "0" to the 2-digit register in STEP99, put "7" in the 1-digit register, and copy "b" to the 2-digit register in STEP96. Copy “4” into the 1st digit. In STEP 78, R11 is reset to bring the copy operation to an end, and in STEP 79 to STEP 90, the indicators "b", "4", "0", and "7" are displayed. That is, "b", "4", "0", and "7" indicate an abnormality in the optical system backward movement signal at the end of the optical system reciprocating movement.

If there is no abnormality in the optical system reverse signal,
In STEP100, it is determined whether the voltage level of the sequence check start signal is "1", and if the start signal is "1", STEP65
Return to , repeat the copy operation, and perform a sequence check.

If the voltage level of the start signal is "0", the process advances to STEP101. In STEP 101, after counting 290 drum clocks, that is, at time _T7 in the time chart of FIG. 12, it is determined whether "1" is set at the main motor/high voltage transformer operating signal input terminal Y12. That is, at time _T7 in the time chart of FIG. 12, it is determined whether the main motor and high voltage transformer operating signals have already stopped. If “1” is on terminal Y12,
In STEP103, put “0” into the set 2-digit register, in STEP104 put “1” in the set 1-digit register, in STEP104 put “b” in the copy 2-digit register, and copy “1” into the 1-digit register. put it in the register. Thereafter, in STEP78, R11 is reset to bring the copy operation to an end, and in STEP79 to STEP90, "b", "1", "0", and "1" are displayed on the display. That is, "b", "1', "0", and "1" indicate an abnormality in the main motor and high voltage transformer operating signal at the time of copy completion. If "0" is set in Y12 Since everything is normal, the process returns to STEP 57 and waits for the start signal to be input again.

<Effects> As described above, according to the present invention, even when using a dynamic display device controlled by a program control means, it is possible to keep the display duty ratio approximately constant, and it is possible to eliminate display flickering. In addition, the stop key and data input key can be input from the same input configuration, simplifying the key input configuration. Moreover, during the image formation period, key input from the data input key is disabled on the condition that image formation is in progress, so the periods during which the data input key and stop key can be accepted are different even though the key input configuration is the same. can do. Furthermore, since the same scanning signal is used for key input scanning and dynamic display, key input can also be executed reliably.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of an electronic copying apparatus to which the present invention can be applied, FIG. 2 is a conventional control circuit diagram, FIG. 3 is a diagram showing a display switching subroutine, and FIG. 4 is a control system of FIG. A diagram showing the output time chart of each part of
5 is a diagram showing a part of a flowchart for operating the control circuit of FIG. 2, FIG. 6 is a drum clock pulse waveform diagram, FIG. 7 is a control circuit diagram of an embodiment of the present invention, and FIG. 10 to 10 show control flowcharts of this embodiment, FIG. 11 shows display output time charts during copy stop and copy operation, and FIG. 12 shows various parts of the microcomputer MC2 in FIG. 7. FIG. 3 is a diagram showing an output time chart. In the figure, 11 is a drum, 11a is a clock board, 11b is a sensor, MC0, MC2, MC2 are one-chip micro computers, KM,
KM' is the key input matrix, DD, DD' are the display decoders, SET1, SET1', SET2, SET2',
COPY1, COPY1', COPY2, COPY2' is 7
The segment indicators, DCK, each indicate a drum clock pulse.

Claims (1)

[Scope of Claims] 1. An image forming means comprising a plurality of processing means for executing image formation; a multi-digit dynamic display means capable of dynamically displaying data related to image formation by the image forming means; a plurality of keys including a data input key for inputting data and a stop key for stopping the image forming operation; a memory storing a program for controlling the display of the display means and key inputs of the plurality of keys; and a dynamic display. The control means includes a plurality of output terminals for outputting sequential scanning signals in order to sequentially scan each display digit of the display means and to sequentially scan the plurality of keys. sequentially and repeatedly outputting the scanning signal to each display digit of the display means from an output terminal of the display means to make the duty ratio of the dynamic display approximately constant regardless of the image forming period or the non-image forming period; Using the scanning signals that are repeatedly output sequentially, key input is enabled at all times regardless of the image forming period or non-image forming period. Disable that key input on the condition that
On the other hand, the image forming apparatus is characterized in that key input to the stop key is always enabled.