JPS63101865A - Controller for copying machine - Google Patents

Abstract

PURPOSE:To simplify the arrangement and racking of a wire harness by constituting the titled controller so that the wire harness from a sensor and a load is connected to an I/O control circuit, and the I/O control circuit and a system circuit are connected by several lines. CONSTITUTION:A system control circuit 10 is placed under an operating board in front of a copying machine, and an I/O control circuit 30 is placed along a back plate which is opposed by placing a copying machine front opening/ closing plate and a copying processing mechanism which are facing an operator, between them. The wire harness from most of sensors and loads is connected to the circuit 30, and the circuit 30 and the circuit 10 are connected by several pieces of lines. The wire harness to each element for a copy processing and the sensor which exists therein from the circuit does not exist substantially, and it is connected to the wire harness from the circuit 30. Accordingly, the wire harness extending from the upper part of the copying machine to a copying processing element of each part in the copying machine is eliminated substantially, and the arrangement and racking of the wire harness are simplified, and also, it becomes short and the high efficiency is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electrophotographic copying machine, and in particular, to setting and turning on the operating level of each element that performs copying processing such as exposure, development, paper feeding, transfer, and fixing. /Related to a control device that performs off-sequence control.

■Prior Art The control device of a conventional copying machine includes a main control unit that determines the copying sequence, and an input/output control unit that reads input from the operation board and displays output.

An exposure scanning control unit that controls the exposure scanning optical system; and AC system elements such as the main motor, fixing heater, charger/transfer charger, and exposure lamp that receive alternating current or direct current power from an energizing circuit connected to the ACffi source. It is a combination of many units, such as an AC system control unit that controls the system, and each unit exchanges data using serial or parallel signals.

Furthermore, various electrical elements (loads) and sensors were connected to each of the main control unit, exposure scanning control unit, and AC system control unit.

It has been found that such conventional control devices have the following problems. That is, (1) Since each unit is configured on one control board, four control boards are required, resulting in a large number of parts and high cost.

(2) For communication between each control unit, there are many lines in the case of parallel communication, and communication control becomes complicated in the case of serial communication, which cannot be used in high-speed copying machines.

(3) Each control unit is connected to sensors that detect the various electrical elements (loads) it controls and their output states, so the wire harnesses are not assembled into one set as a control device, and it takes time to implement the wire harnesses. It takes.

(4) The system will not operate unless all control units are completed and fully connected as specified. In other words, it is not possible to perform a test operation (operation test) on a unit alone.

In order to eliminate these problems, the main control unit, input/output control unit, exposure scanning control unit, and AC system control unit are divided into two, and the main control unit and input/output control unit are combined into one unit (main input/output control unit), and an exposure scanning control unit and an AC system control unit as one unit (exposure scanning/A
As the C-system control unit), a control device configuration that connects the two can be considered.

However, this configuration also has the following drawbacks.

In other words, the operation section must be located at the front of the copying machine, and the mounting space for the control board containing the main input/output control unit is small.On the other hand, the main input/output control unit is equipped with all the sensors involved in the copying sequence. Since the input/output lines are connected to the copying machine and the load, a wire harness consisting of more than 100 electric wires must be connected, and most of the sensors and loads are located on the back side of the copying machine. Therefore, when configuring two units like this, a 100-pin or more connector should be installed on the main input/output control unit on the front of the copier, and 100 or more thick wire harnesses should be routed from that connector to the back of the copier. This leaves us with no choice but to adopt an extremely inefficient implementation form.

(1) Purpose It is an object of the present invention to provide a copying machine control device that simplifies the arrangement of wire harnesses, thereby simplifying the structure of a copying machine, particularly the arrangement of wire harnesses, and reducing costs.

■Structure In order to achieve the above object, in the present invention, an operation board having keys for input operation by an operator; and photoreceptor rotation synchronization pulse generation means; in response to the scanning speed target value,
The lens/mirror position target value for zooming, the lamp voltage target value, and the developing bias voltage target value are given to the second microprocessor below, and in response to the operation of the start key on the operation board, the following second microprocessor is executed in a predetermined sequence. a first microprocessor which supplies an on/off instruction signal for the means connected to the microprocessor and a start/return instruction signal for the scanning means to the second microprocessor via serial communication;
a microprocessor; a photoconductor drive energizing means for electrically energizing a photoconductor drive means for rotationally driving the photoconductor; a charge energizing means for electrically energizing a charging means for charging the surface of the photoconductor; An exposure lamp illuminates the image of the original, and an exposure mirror projects the reflected light from the original onto the surface of the photoreceptor.

Variable magnification exposure scanning means consisting of a variable magnification lens/mirror that adjusts the magnification of the image projected onto the surface of the photoreceptor, and scanning means that scans the image on the document by scanning the original and one of the exposure mirrors relative to each other. Variable magnification exposure scanning biasing means for biasing the electric element; Development biasing means for electrically biasing the developing means for visualizing the exposed surface of the photoreceptor; Transfer means for transferring the developed image on the photoreceptor onto recording paper. A transfer biasing device that electrically biases the recording paper; a paper feed biasing device that electrically biases the paper feeding device that supplies the recording paper to the transfer device; and a fixing device that heat-fixes the transferred recording paper. an exposure lamp voltage detection means; a variable magnification lens/mirror position detection means; an exposure scanning position detection means; an exposure scanning synchronization pulse generation means; a developing bias detection means; and a fixing temperature detection means; The biasing means is electrically connected, positions the variable magnification lens/mirror at a position corresponding to a target value of the variable magnification lens/mirror position, and responds to the on/off signal and the start/return signal. The exposure lamp is controlled at a constant voltage according to the lamp voltage target value and the exposure lamp voltage detection value, and the scanning speed is controlled according to the scan speed target value and the exposure scan synchronization pulse. is controlled at a constant speed,
The developing bias is controlled at a constant voltage in accordance with the developing bias voltage target value and the developing bias detected value, and the detection state of the detection means is read at a predetermined timing and the first
a second microprocessor for supplying the second microprocessor to the second microprocessor;

That is, the control device of the present invention will first be briefly described as follows.
Loads and sensors that require connection of many wire harnesses are not connected to the first microprocessor, which is the main component of the main input/output control unit and is located near the operation section on the front of the copying machine. However, since the pulse generating means that generates the photoreceptor rotation synchronizing pulse that serves as the timing reference for sequence control uses the first microprocessor to count the pulses and advance the sequence, the pulse generating means Since it can be located in close proximity to the microprocessor, it is connected to the first microprocessor. Also, A
External copy function-enhancing elements or devices such as DF that are located near the operation board, and additional elements or devices that are required within the copier body when such elements or devices are installed, Connect to the first microprocessor as needed. Other copying functional elements or devices and sensors are connected to the second microprocessor for serial transmission/reception of required data between the first and second microprocessors.

In order to cope with the increase in the amount of control tasks and the number of input/outputs that accompany the multifunctional demands of copiers, it is common to simply increase the number of microprocessors and ports, but this not only increases costs but also , communication control between microprocessors becomes complicated. In other words, it becomes extremely difficult to determine the tasks of each microprocessor, leading to bugs.

Furthermore, the time required for communication between microprocessors becomes longer, making it impossible to perform the original task.

Therefore, the best method is to process a number of tasks in parallel by multitasking, which allows one microprocessor to perform as many tasks as possible, as in the second microprocessor of the present invention described above. Also, if the main control unit, which is the brain, and the input/output control units, which are its arms and legs, are mounted on the same board, as in the past,
Unless the brain is fully developed, the limbs cannot move freely, but in the present invention, as mentioned above, this problem is solved by separating sequence control and input/output control between the first and second microprocessors. was resolved. As a result, (1) the system configuration is simple and clear, the number of parts is small, and program design becomes easy; Also,(
2) Since the first and second microprocessors can each be operated independently, debugging becomes easier and the development period is shortened.

FIG. 1 shows an outline of the configuration of the control device of the present invention.

In FIG. 1, a system control circuit board 10 is schematically a conventional main and operation control board combined into one board, but without connections to conventional loads and sensors. A first microprocessor (11: FIG. 3) is mounted on this circuit board 10.

The I10 control circuit board 30 is roughly a control circuit board that combines a conventional exposure scanning control unit, AC system control unit, and main input/output control functions.
A microprocessor (31: Fig. 4)) is installed.

In the implementation form, the system control circuit board 1O is placed below the operation board on the front of the copying machine, and the I10 control circuit board 3
0 is arranged along the front opening/closing plate of the copying machine facing the operator and the opposing rear plate with a copy processing mechanism such as a photosensitive drum placed therebetween. Wire harnesses from most sensors and loads are located at I1 on the back of the copy processing mechanism.
0 control circuit board 30, and I10 control circuit board 3o and system control circuit board 10 are connected by several lines.

With the above-described configuration, the control device of the present invention has the following effects in addition to the above-mentioned effects. That is,
System control circuit board 10 around the operation board on the top of the copying machine
There are virtually no wire harnesses to the copy processing elements and sensors therein, which are connected to a wire harness from the I10 control circuit board 30 at the back of the copying mechanism. Therefore, the wire harness from the top of the copying machine to the copying processing elements in each part of the copying machine is virtually eliminated, and the wire harness arrangement becomes simple, short, and highly efficient.
The work efficiency of assembling the control device into the copying machine has improved,
This reduces the cost of copying machines.

Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings.

FIG. 2a shows an outline of the configuration of an embodiment of the present invention in terms of functional elements, FIG. 3 shows the configuration of the system control circuit board 10 shown in FIG. 2a, and FIG. 4 shows the I10 control circuit board 30. Indicates the constituent entities of.

First, referring to FIG. 2a, an overview of the configuration of the control device will be described. The system control circuit board 10 (first microprocessor 11: FIG. 3) shown in FIG. 2a performs the following processing.

(1) Read the key power on the operation board 28 and the connection status of external additional devices for improving the copying function, and select the copy mode (manual copy, copy using ADF, 1-image composite copy, key card response copy, etc.) and the conditions ( Mode and condition control that determines the number of continuous copies, copy density, copy magnification, etc.) and outputs the mode and data contents to the display.

(2) Count the drum encoder clock (drum synchronization pulse) whose frequency is synchronized with the linear velocity of the copying process (peripheral velocity of the photoconductor drum), and perform the paper feeding and image forming sequence at the timing according to the copying mode and conditions. Sequence control that generates timing signals (on/off signals) to advance the process.

(3) Send the target value according to the above copying conditions and the above timing signal to the I10 control circuit board 30, and from the I10 control circuit board 30 state information of each element of the copying process (exposure lamp voltage, fixing temperature, bias voltage size.

Serial transfer communication to receive paper detection, etc.).

(4) External devices such as ADF (automatic document feeder), editor (image editing device), etc. to improve copying functions have input/output with additional devices, same as ECD (device for imprinting date, page, etc.) Input/output of Input/output to image density sensor (used for toner density control).

That is, the copy sequence is controlled by the system control circuit board 10, but the output data of that sequence is transmitted via the serial communication line to the I10 control circuit board 3 described below.
0 is input from each sensor and output to each load.

I10 control circuit board 30 (second microprocessor 31
: FIG. 4) performs the following processing.

(1) Constant speed control of the scanner (image scanning) drive servo motor of variable magnification exposure scanning system 31. Positioning control that controls the position (magnification setting) of the variable magnification lens and mirror drive step motor.

(2) Light amount control of exposure lamp, temperature control of fixing heater,
AC system control that performs on/off control of the main (photoreceptor) II motor.

(3) Development bias voltage control.

(4) Detection of copy paper size, original size, copy paper conveyance position, etc., paper feeding, drive of each registration conveyance means, charging, high voltage for corona generation of transfer two-separate charger? ! The I10 control controls all input/outputs other than those performed by the system control circuit board 10, such as energizing the source, developing roller, and toner replenishing means.

(5) System communication for serially communicating with the system control circuit board 10 the data input and output by the I10 control, and the status and instructions of the optical system, AC system, and bias control.

FIG. 3 shows the main elements of the system control circuit board 10. The main body is a microprocessor 11, which includes a processor 11, a ROMI 2. RAMI 3. Serial IJ communication element 14. Address latch 16 and input/output port 17 are connected. ROM12°RAM13. The serial communication element 14 and input/output ports are designated by the address decoder 15. AND gates 21 to 23 perform this.

The serial transfer line of the microprocessor 11 includes an I
The serial transfer line of the microprocessor 31 of the 10 control circuit board 30 is connected. Further, an ECD 71 and an editor 70 are connected to the microprocessor 11 via external connectors as necessary. counter(
Total number of copies cumulative counter for maintenance fee calculation)
24 and a drum encoder (drum synchronous pulse generator) 25 are fixedly connected. The eraser 29, which is used for writing additional information such as the date using the ECD 71, for erasing the mask part in image editing using the editor 70, and for erasing dark spots when reducing the size, is also connected to the microprocessor 11 via the gate 18. has been done. ADS
67 is an A/D converter capo of the processor 11.
1, and the P sensor 19 is connected to the A/D conversion port ANO of the processor 11.

Operation board 28 and display board 27 are input/output port 1
7, and a notification buzzer 26 disposed near the operation board 28 is also connected to the input/output port 17.

The ADF is connected to the serial communication element 14 via a connector as necessary, and the monitor 72 is connected to the system bus (
address bus (table data bus) and control lines.

FIG. 4 shows the main elements of the I10 control circuit board 30.

The main body is a microprocessor 31;
ROM32. Timer 33. Address decoder 34.
Address latch 35. Input/output ports 36.37 and gates 38.39 are connected.

The serial transfer line of the microprocessor 31 is connected to the serial transfer line of the microprocessor 11 of the system control circuit board 10.

Exposure scanning of the variable magnification exposure scanning system (Figures 12a to 12c) (
One of the pulses A and B generated by the scanner encoder 59 (coupled to the motor 58), which generates two sets of pulses A and B whose phases are shifted from each other in synchronization with the rotation of the scanner motor 58), is frequency-divided. A branch pulse is applied to the processor 31. This frequency-divided pulse is counted by the microprocessor 31. Pulses A and B are applied to a flip-flop 41 for detecting the rotation direction, and the flip-flop 41 provides a signal indicating the rotation direction to the processor 31. Also, a scanner home position sensor 5 detects that the scanner is in the standby position.
7 is connected to the processor 31. A lens home position sensor 53 detects that the variable magnification lens 84 for setting the copying magnification is at the position of magnification 1, and a variable magnification mirror 82 for setting the copying magnification (corresponding start position).
A variable magnification mirror home position sensor 55 is connected to the processor 31 and detects that the mirror 83 is at the start position with a magnification of 1.

a motor driver that energizes a step motor 54 for driving a variable magnification lens; a motor driver that energizes a step motor 55 that drives a variable magnification mirror to a start position corresponding to the magnification;
A motor driver that energizes the step motor (PW in 74) that feeds the recording paper that has been copied on one side for back side copying of the duplex unit 74, and a motor driver that energizes the step motor (PW in 74) that feeds the recording paper that has been copied on one side for back side copying, and - A motor driver that energizes the step motor (PW in 75) that feeds paper for double-sided copying is connected to the processor 42 via the selector 42. Note that the latter two motor drivers are connected to the selector 42 via connectors.

A lamp driver that energizes the exposure lamp 61 and a first heater driver that energizes the heater 1 of the fixing device.

A second heater driver that energizes the heater 2, a motor driver that energizes the main motor (main power source; drives photoreceptor rotation, paper feeding, conveyance system, etc.), and stably feeds the transferred paper. A fan 65 for sucking negative pressure from a suction device for sucking transferred paper, which is installed in the paper feed line from the transfer unit to the fixing device.
An AC (alternating current) driver 6 consisting of a motor driver that energizes the motor, and a zero cross detection circuit zcp that generates a pulse (zero cross pulse) at the zero cross point of the main power AC.
0 is connected to the output port of the processor 31 via an output buffer 43.

The original size sensor 68 is connected to the A/D conversion input ports AN5 and ANA of the processor 31, and the bias voltage detection signal line of the developing bias circuit BIAS of the developing device 51 is connected to the A/D conversion input port N2. The temperature detection signal line indicating the fixing temperature around the heater 1 of the fixing device is connected to the A/D conversion input port ANI, and the lamp voltage detection signal line of the lamp driver of the AC driver 60 is connected to the A/D conversion input port ANI. Conversion conversion input boatro No.
It is continued.

The input/output boat 35 temporarily stops the paper fed out from the cassette just before the transfer position, and supplies the paper between the transfer charger and the photoconductor drum in synchronization with the movement of the toner image on the photoconductor drum. A clutch driver that energizes the registration roller clutch that connects the registration roller to the power transmission system of the main motor 64, a detection potential signal line of the latent image potential detection circuit of the development unit 51, and a detection potential signal line of the development unit 51.
A clutch driver that energizes the developing roller clutch that connects the developing roller to the power transmission system of the main motor 64, and a clutch driver that energizes the clutch of the stirring roller that controls the toner charging potential.

Static elimination LED that erases the outside of the image exposure area on the photoconductor
A solenoid driver that energizes a solenoid 52 for inserting and removing a red erase filter 50, a paper feed clutch that feeds recording paper from a cassette to a registration roller, and a driver that energizes a solenoid are connected. The input/output boat 36 has a paper feed scan output end PO and a paper feed scan input end Pi, P4. During P5, there are also paper sensors placed in the paper feed section (cassette mounting section) for detecting paper size and presence, and paper sensors placed between the paper feed section and the paper ejection section for detecting paper movement timing and jam detection. The paper sensor 45 is
Connected in a matrix configuration.

The input/output boat 37 includes a main charger, a high voltage circuit that energizes a grid 66 that switches the corona voltage applied to the surface of the photoreceptor.

A high voltage generation circuit 49 that energizes the transfer/separation charger and the static elimination charger at high pressure and the output selection signal A line of the data selector 42 are connected, and the double-sided unit 74 and the synthesis unit 75 are connected via connectors. A key card read/write device 76° sorter 73 is connected. The processor 31 provides a forward/reverse instruction signal to a motor driver that energizes the scanner motor 58 via a gate 38, and also provides a developing bias circuit BIAS via a gate 39.
gives an on/off signal to the A monitor 77 is connected to the pass line and control signal line of the microprocessor 31 via a connector.

Next, the microprocessor 1 of the system control circuit board lO
1 and the microprocessor 31 of the I10 control circuit board 30 for exchanging data will be described.

FIG. 5 shows the circuit board 30 from the processor 11 of the circuit board
3 shows data to be sent to the processor 31.

6, from the processor 31 of the circuit board 30 to the circuit board 10
The data transmitted to the processor 11 is shown in FIG.

Transmission data is 14 bytes each (1 frame 1
4 bytes; since the synchronization character is 1 byte,
If this is included, one frame is 15 bytes), and 1 frame division for transmission and reception, and 1 indicating the beginning of one frame.
Since the byte synchronization character data is OF F +1, each of the other 14 bytes of data is 0F.
F) It is set so that it does not become l.

The communication data shown in FIGS. 5 and 6 will now be explained. In both FIGS. 5 and 6, the horizontal axis represents bits in one byte, and the vertical axis represents bytes.

First, communication data sent from processor 11 to processor 31 will be explained. In FIG. 5, the O-th byte is a synchronization character, which is data for byte synchronization between the transmitting side and the receiving side.

The first byte contains 4-bit development bias level and 3-bit exposure level data, the development bias voltage has 16 levels, the exposure brightness has 8 levels, and indicates the development bias voltage and the brightness of the exposure lamp. It is something to do.

The second byte is a signal in which the 0th bit instructs the main motor 64 to be turned on or off, and the 1st bit to instruct the fan motor 65 to be turned on or off. The second and third bits are signals that instruct the scanner to start and return, and the fourth to seventh bits
The bit is a signal that instructs on/off the clutch solenoid that connects the paper feed roller to the main power system.

The 0th and 1st bits of the third byte are connected to the registration roller clutch for aligning the leading edge of the image on the copy paper and the drum, and the intermediate clutch for transporting the copy paper from the duplex 1 composition unit 74-75 to the registration roller. The second to sixth bits, which are signals for instructing on/off, are signals for instructing to turn on/off the developing roller, etc. of the developing device.

The 0th to 4th bits of the fourth byte are the main charger energizing circuit of the high voltage generator 49 and the transfer charger energizing circuit 2.
This is a signal that instructs on/off to the component transfer charger energizing circuit 9, the separate charger energizing circuit, and the component separation charger energizing circuit, and the 5th bit turns on/off the charge removal LED 50.
Signal indicating off.

The 6th and 7th bits are on/off instruction signals for the grid 66 which switches the corona voltage of the main charger.

The 0th, 1st, and 4th to 6th bits of the fifth byte are on/off instruction signals to the composite copy unit 75. The third bit is a signal to cut the red component of exposure, that is, a red erase solenoid on/off instruction signal. be.

The 0th to 2nd bits of the 6th byte are the duplex copy unit 7.
The fifth and sixth bits are signals for instructing alignment of copy sheets in the combining and duplexing units 75 and 74, and the seventh bit is a count-up instruction signal for the key card.

The 0th to 2nd bits of the 8th byte are energizing signals to the sorter 73.

The 9th byte is key card data.

Bits φ to 3 of the 10th byte are vertical magnification adjustment data, that is, scanner speed adjustment data, and fourth to seventh bits 4 to 7 are horizontal magnification adjustment data, that is, lens and mirror position adjustment data.

The 0th to 3rd bits of the 11th byte are lead edge (image leading edge) adjustment data, and the 4th to 6th bits are signals for testing the scanner and lamp bias independently.

The 12th to 14th bytes are each setting data of the exposure lamp voltage median value, fixing heater temperature, and development bias voltage median value.

As described above, the microprocessor 11 of the system control circuit board 1O sends on/off instruction signals for each load, commands and data for variable magnification exposure scanning system control, and commands for AC system control to the microprocessor 31 of the I10 control circuit board 30. and data, and development bias control data are sent.

Next, communication data sent from processor 31 to processor 11 will be explained. In FIG. 6, the Oth byte is a synchronization character.

The 0th and 1st bits of the first byte are the scanner's home information signal and the highest digit If! (Limit position II) This is a signal representing a detection signal, and the 3rd to 6th bits indicate a signal indicating the fixing glue load (the temperature that allows fixing has been reached), a signal indicating overheating, and a disconnection of the thermistor for detecting the fixing temperature. It's a signal. The 6th and 8th bits are signals indicating the status of the exposure lamp 61 (on or off) and the exposure lamp abnormality (leaving it on).

The first and second bits of the second byte are signals for testing the scanner and exposure lamp independently (this signal is also shown in Figure 5, but is intended to allow testing from either processor 11 or processor 31). ) and the second
7 bits are detection signals of the latent image potential sensor and toner potential sensor of the developing section.

The 0th and 1st bits of the third byte are door opening/closing signals for the copying machine main body, and the 2nd to 4th bits are copy paper detection signals for the registration roller section, fixing section, and paper ejecting section.

The 0th to 3rd bits of the fourth byte are the signals from the sensor of the combining unit 75, and the 3rd to 7th bits are the signals from the sensor of the duplex unit 74.

The 0th to 3rd bits of the 5th byte are the sensor signals of the sorter 73, and the 4th bit is the key card insertion detection signal.

The 0th to 4th bits of the 6th byte are the -th paper feed section (cassette)
The 6th bit is a manual paper detection signal, and the 7th bit is a toner overflow detection signal.

The seventh to ninth bytes are a paper size detection signal and a paper presence/absence detection signal for the second to fourth paper feed sections.

The 10th byte is abnormal state data of the variable magnification exposure scanning system.

The 11th to 14th bytes are exposure lamp voltage detection data, fixing temperature detection data, bias voltage detection data, and document size detection data.

As described above, from the microprocessor 31 of the I10 control circuit board 30 to the microprocessor 11 of the system control circuit board 10, detection signals (on/off) and detection amount data from each sensor, variable magnification exposure scanning system, and AC system are transmitted. status (on/off) signals and output status data are sent.

An outline of the control operation of the microprocessor 31 of the I10 control circuit board 30 will be explained based on the circuit diagram of FIG. 4 and the general flowchart of the main routine of FIG. 7a.

First, when the power is turned on, a reset signal is output from the microprocessor 11 of the system control circuit board 10 to the terminal RESET of the microprocessor 31, and the processor 31 is activated. Then, the processor 31 performs the following initial settings (step 1 in FIG. 7a; hereinafter, the word "step" will be omitted in parentheses).

- Specify input/output for all ports, and set an off signal to the port specified as output.

■ Clear internal RAM (processor 1 used in this example)
1.31 has 256 bytes of built-in RAM).

■Specify the serial communication mode (asynchronous method).

Enable receive interrupts. As a result, when the microcomputer 11 receives a transmission, it executes a reception interrupt (described later) in FIG. 7b.

(2) Set the interval timer 33 for controlling the variable magnification exposure scanning system (20K) 12), details of which will be described later.

(2) Scanner homing flag and lens homing flag set (moves the scanner and lens to the forming position when the power is turned on. Sets a flag indicating the start of this. Details will be described later.

Next, check whether the frequency of the AC power supply has been detected 2.
), if the frequency has not been detected, the frequency detection routine (
3) Haejanbu. Here, at the first call (when proceeding to frequency detection (3) for the first time), the internal timer is set to 0.
．． Set 5 seconds and start the internal timer.

When proceeding to frequency detection (3) from the second time onwards, the frequency counter (FRQCNT) is incremented each time a lock loss pulse appears, that is, each time a zero cross of the alternating current is detected. That is, a zero-crossing pulse is input to the INT1 terminal, and when the zero-crossing pulse occurs, the interrupt flag F1 is set to 1, and Fl is checked to determine a zero-crossing. When Fl exists, that is, once a zero cross is detected, zero cross interrupts and timer interrupts are masked. Therefore, frequency detection (3) → optical system control (13) → I10 control (14) is performed for 0.5 seconds.
When 0.5 seconds have elapsed, a timer flag FTI indicating this is set, and if this flag is present, the count value of the frequency counter (FRQ) is set in frequency detection (3).
CNT) x y') L/, (FRQCNT)
> 55 (71 hours 60H2, (FRQCNT)≦55
When the frequency is 50Hz, it is determined that the frequency is 50Hz, and the determination data is set. This is the content of frequency detection (3).

After frequency detection (2) is completed, lamp control (5) → heater control (8) → bias control (11) → optical system control (1)
3) → I10 control (14) loop.

Note that a zero-cross interrupt (
Interrupt processing in response to zero cross pulse of AC power supply: 7th
Figure c) is allowed.

During this series of repetitions, if the lamp flag is set, lamp control (5: setting of target value of lamp voltage and updating of phase angle timer) is performed, and then the lamp plug is reset. The lamp flag is set when the lamp voltage is read from the ANo terminal.

If the heater flag is set, one control of the fixing heater (setting a target value of the heater temperature and updating the heater duty) is performed, and then the heater is reset. The heater flag is set every 1 sec.

Similarly, if the bias flag is set, bias control is performed (bias duty is updated when the bias voltage is on), and then the bias flag is reset. The bias flag is set when the bias voltage is read from the AN2 terminal.

I10 control (14) reads input signals such as sensors and signals (data) received from the system controller.
The output of the clutch, etc. is turned on/off based on the

When the time set in the phase angle timer (TMO) in the zero-crossing interrupt routine (FIG. 7C) arrives, a timer interrupt is generated and a jump is made to the timer interrupt routine (FIG. 7D).

FIG. 4c shows a flowchart of a real reception interrupt executed by the microprocessor 31 in response to a transmission from the microprocessor 11. In this embodiment, in the serial reception interrupt, the processor 31
11. That is,
When there is a transmission from the processor 11 to the processor 31, the processor 31 reads the transmission data due to a reception interrupt, and then the processor 31 transmits the monitored data to the processor 11.

To explain this reception interrupt (Figure 7b), when the processor 31 receives a transmission from the processor 11 and proceeds to the reception interrupt in response, it first checks to see if there is a reception error (15). In this case, check whether the data is a synchronization character (OFFH) (16), reset the reception address counter to 0 only if it is a synchronization character (17), then store the received data in memory (18), and then If the data is for a variable magnification exposure/scanning system (19), the received data is processed (20); if it is for a system other than the optical system, this is done in the main routine. Further, in the case of an error (15), the above processing is not performed.

When the reception is completed, the reception address counter is incremented (21), and if it exceeds (count value 15 in this case), the counter is reset (set to 0) and the process moves to the transmission routine (24 to 30).

In the transmission routine (24 to 30), data at the address indicated by the transmission address counter is transmitted (24.25),
Then increment the sending address counter (2
6) If the count exceeds (15 in this case), the counter is reset (30).

If the transmission counter is greater than 1 and there is variable magnification exposure scanning data to be transmitted next, the transmission address counter is reset (29.30), which means that variable magnification exposure scanning data is sent with priority. It is for this purpose. Thereafter, the watchdog timer is processed (31, 32) and the process returns.

Watchdog timer 1 (31) is used to detect abnormalities in the pulses generated by the encoder 59, and is normally reset by an interrupt from the encoder pulse. Therefore, if the encoder pulse does not come in, the timer count overflows, indicating an abnormality. In step 31, a watchdog timer l is set.

The watchdog timer 2 (32) is for detecting an abnormality in the exposure lamp 61, and normally controls the exposure lamp 61 on and off, but is a timer that treats it as an abnormality if it does not turn off after a certain period of time. Yes, step 32
Now set watchdog timer 2.

Every time the AC power passes the zero cross point, the AC driver 6
0 zero cross detection circuit ZCP generates a zero cross pulse, which is sent to the interrupt terminal IN of the microprocessor 31.
It is input to Tl. In the processor 31, a zero-crossing interrupt occurs at the rising edge of the zero-crossing pulse, and the process jumps to the zero-crossing interrupt routine shown in FIG. 7c. Note that the frequency detection (3) of the main flow shown in Fig. 7a
), zero-cross interrupts are enabled.

To explain the contents of the zero-cross interrupt processing with reference to FIG. 7c, first, the drive signal (
Turn off the exposure lamp on/off signal, heater on/off signal, and main motor on/off signal (33: This is the zero-crossing point of the AC power supply) 0 Next, read the data (original size) of AN4 to AN7 (34: respectively l/2
If it is higher than AVref, it is 1.1/2, if it is less than AVref, it is O.) After storing it in the internal RAM, change the A/D conversion mode to A N □ = 3 (35: that is, the current start A/D conversion from AN, ~3).

Next, it is checked whether the exposure lamp start signal is on or off (36).This signal is sent to the processor 1 after about 0.3 seconds in response to the copy start key being pressed.
1 as an exposure start-on signal (data), and this is sent continuously until the scanner returns. Then, when the scanner returns, an exposure start-off signal (data) is sent. When the exposure start signal is off, the off-time phase angle timer data 117 is set in the phase angle timer (TMO) (37). The phase angle timer starts from 0 and is incremented every 38.4 μsec, and A timer interrupt occurs when the value becomes equal to the set value. That is, if the phase angle timer is started from the zero cross point, 117X38.
A timer interrupt occurs after 4μ5ec=4.5+5sec. When the exposure start signal is on, the phase angle timer (TMO) is set to the lamp control routine (Figure 10a; described later).
The phase angle timer (PllANGL) obtained in step 38 is set.

Next, the phase angle timer is started from 0 (39). Enable timer interrupts.

Next, check the fixing heater on counter (FUCNT) L (40), and if (FUCNT) is not O, then (FUCNT) is checked.
LICNT) is decremented (41), and the fixing heater on/off signal is turned on (42). This is FBI
Output from the terminal. Here, (FUCNT) is calculated based on the fixing heater temperature in a fixing heater control routine (FIG. 8, described later).

Next, it is checked whether the main motor on/off signal is on or off (43). This signal is immediately sent from the processor 11 as a main motor on signal (data) when the copy start key is pressed, continues to be sent until the copy is completed, and is changed to a main motor off signal (data) after the copy is completed. It is something that is sent to you. If the main motor signal is on, the main motor drive signal is turned on (44), which is output from the PB4 terminal.

Finally, check the fixing heater control counter (HTCNT).45) If (HTCNT) is not 0, then (HTCNT)
CNT) is decremented (46). (HTCNT
) is 0, a heater flag is set (47). (H.E.
TCNT) is a 1 sec counter, so 1 sec
The heater flag is set every c. Therefore, heater control (FIG. 8) is performed every 1 sec.

Once the effective value (RMS) of the lamp voltage is determined, a phase angle timer (PHANGL) is calculated. However, this applies only when the exposure lamp pro N mode is used. Now, to update the phase angle timer, turn on the exposure lamp and then update the target value (SFTRMS).
) is reached using the formula below.

(PHANGL) = (PHANGL) - (DIF
F) When the target value is reached, calculate it using the formula below.

(PHANGL) = (PI(ANGL) −((S
ETRMS) - (RMS)) Finally, check the lamp lighting. That is, when the lamp is lit, a lamp ON signal (data) is set to be sent to the system controller, and the watchdog is activated. If the lamp is off, reset the lamp ON signal (data) and stop the watchdog timer. The watchdog timer will be explained in the reception interrupt routine, but if the lamp remains on for 20 SEC or more, the I10 controller forcibly outputs "'HI" from PBφ and turns it off.

Next, in the zero-crossing interrupt routine, the phase angle timer (TMO)
), a timer interrupt occurs, and
Jump to the timer interrupt routine (Figure 7d).

To explain the contents of the timer interrupt routine with reference to Fig. 7d, first, the timer is stopped (48), and then it is checked whether the exposure lamp is on mode or off mode (49).If it is on mode, the lamp drive Turn on the signal (50: Output from PBo terminal).

The waveform of the lamp drive signal is shown at C in FIG. 10b.

Next, the analog data of AN, ~3 (A Na is unused) is read and stored in the internal RAM (51). In other words, the analog data of AN (the squared integrated value of the lamp voltage) is read and stored in the internal RAM. The register (SU
MLMP) and set the lamp flag (5
2), then AN, analog data (fixing heater temperature)
Read, invert and store in (FUTEMP) (
53). Here, what is reversed is that when the temperature increases, AN
This is because the analog data of l becomes smaller (the relationship between detected temperature and detected voltage is a negative characteristic). Finally, read the AN2 analog data (bias voltage) (BIAS)
(54) and set the bias flag (54).
6).

When the reading of the above analog data is completed, the A/D conversion mode is changed to AN a~7 (56).

That is, A/D conversion of AN4 to AN7 is started from this point.

The aforementioned zero-cross interrupt (Figure 7c) and timer interrupt (Figure 7d) are always activated in synchronization with the zero-cross pulse of the AC power supply after the AC power supply is turned on and the detection of the power supply frequency is completed until the power supply is turned off. Occur. Note that when interrupts are accepted, all interrupts become disabled, so when zero-crossing interrupts and timer interrupts return,
Also, set it to a permitted state (only those that are unmasked).

Next, fixing heater temperature control (8) will be explained. If the heater flag is set (7 in Figure 7a), the heater control (
Execute 8).

FIG. 8 shows a flowchart of heater control (8).

The details of the heater control (8) will be explained with reference to FIG. The value (13th byte in Figure 5) is assigned to the register (SETFUS
). However, in preheating mode, it is lO
Store the value minus .

Next, the on-duty (FUCTC) of the fixing heater is calculated from the following formula (58).

(Team) = KP ((FTNI) - (FTNO)) + KI
((SETFUS)-(FTN 0))(FLICYC
) = (FUCYC) + (EM) Here, KP and KI are constants determined by the characteristics of the fixing heater, and (FT
NO) is the current fixing heater temperature, and (FTNI) is the previous fixing heater temperature (1 sec ago). Also, (F
UCTC) is 0 to 100/120 (50H2/60H2
) D control (58).

The value controlled above is also stored in (FυCNT), but in the exposure lamp lighting mode, the heater temperature is (SETFU
If it is greater than or equal to (SETFUS), set it to 0, and if it is less than (SETFUS), set it to 100/120 (50) 12/60H2) (58).

This process is performed at the start of exposure and remains fixed until the exposure lamp is turned off.

Next, check the fusing heater temperature as shown below (5
9).

■Overheating (when the heater temperature exceeds 225°C).

■Thermistor disconnection (heater temperature is O”C for 10 seconds or more)
or higher).

■Pre-reload [Heater temperature (SETFUS) -15
reached].

■Reload [Heater temperature reached (SETFUS) -5].

If each of the above ■ to ■ corresponds to the above, transmitting a signal (data) indicating the corresponding contents to the processor 11 (59);
Finally, 100/
Set 120 (50H2/601iZ) (60)
.

Next, bias voltage control (11) will be explained. 9th
The figure shows a flowchart of bias control. In the main flow shown in FIG. 7a, the presence or absence of a bias flag is checked (10), and if the bias flag is set, bias control (11) is executed.

Bias control (11) will be explained with reference to FIG. 9. First, the target value is determined by the bias level (bits 0 to 3 of the first byte in FIG. 5) sent from the microprocessor 11 side. settings 61-63), then A/
The duty of PVM (pulse width modulation; pulse width control of pulse energization) is controlled by PI calculation so that the voltage level reaches the target value from the current bias voltage value input to the D input (AN2). (6
4), if the bias level data is 0, (61)
, the bias trigger is turned off (65), the PWM timer is set to the minimum value (here, 1), and (66) the process returns.

Further, the target value of each bias level can be changed by the developing bias voltage setting value (14th byte in FIG. 5) also sent from the microprocessor 11.

Next, lamp control (5) will be explained.

FIG. 10a shows a flowchart of lamp control (5).

In the main flow shown in FIG. 7a, the presence or absence of a lamp flag is checked (4), and if the lamp flag is set, a lamp control (8) routine is executed.

The lamp control (8) will be explained with reference to FIG. 10a.
First, the lamp voltage setting value (the 12th byte in FIG. 5: 5TVLT) and the exposure level (the 4th to 6th bits of the 1st byte in FIG. 5:
N0TCH) to lamp voltage target value (SETRMS)
is obtained using the following formula (67).

(SETRMS) = 10/7 X (STVLT)
+ 4

If the AC power supply is 50) + 2: (DIFF) = 1/18 ((SETRMS) -9
1) +4 When the AC power supply is 60H2: (DIFF) = 2/45 ((SETRMS) -
91) + 4 and the initial value of the phase angle timer 220/
180 (50H2/60)IZ) is set to (PHANGL) (69). Next, the effective value (RMS) of the lamp voltage
) is calculated from the following formula (70).

(RMS) = 121 x (SUMLMP) where,
(SUMLMP) is the ai point of F in FIG. 10b, i=1.
2, 3. ..., which is the value of 2 of the exposure lamp voltage.
Corresponds to the multiplication value. That is, in each cycle of the AC power supply, a phase-controlled voltage D (signal D in FIG. 10b: voltage during a phase interval determined by phase control) is applied to the exposure lamp 61, and the lamp voltage is rectified by E( The signal E) shown in FIG. 10b is input to the terminal AN through the square integration circuit (70), and this input voltage is F shown in FIG. 10b. Once the effective value (RMS) of the lamp voltage is determined, the setting value (time from zero cross point to on start point) of the phase angle timer (PHANGL) is calculated (71). However, this only applies when the exposure lamp is on mode. Now, regarding the update of the phase angle timer (71), the following formula is used from when the exposure lamp is turned on until the target value (SFTRM illusion) is reached.

(PHANGL) = (PHANGL) - (DIFF)
When the target value is reached, it is calculated using the formula below.

(P)IANGL) = (P)IANGL) −((
SETRMS) - (RMS)) Finally, the lamp lighting is checked (72), i.e. the lamp on/off signal sent to the processor 11 if the lamp 61 is lit (
data) and start watchdog timer 2. If the lamp is off, the lamp on/off signal (data) sent to the processor 11 is reset to off) and the watchdog timer 2 is stopped. Watchdog timer 2 is as described in the reception interrupt routine shown in FIG. 7b. Adding an explanation here,
If the lamp 61 remains on for 20 seconds or more, the microprocessor 31 forcibly outputs "HI" from the output port PBo to turn it off (72).

Next, control of the variable magnification exposure scanning system by the microprocessor 31 will be explained. Therefore, first I will explain the premise.

An outline of the configuration of the variable magnification exposure scanning system is shown in FIG. 12a, and FIG. 12b shows the variable magnification lens positioning drive system.

Further, the exposure scanning system and the mirror positioning drive system for variable magnification are shown in FIG. 12c.

Exposure scanning control is performed using an exposure lamp 61 and mirrors 81 to 8.
3 relative to the document on the contact glass plate 78.
control).

That is, the scanning is performed by a scanner power system using the scanner motor 58 as a power source, which is independent of the main power system of the copying machine.

When the power is turned on to the microprocessor 31, the optical fiber 79° exposure lamp 61 is connected to the first document density sensor 67.
Then, the first scanner that drives the carriage on which the first mirror 81 is mounted, the second scanner that drives the carriage on which the second and third mirrors 82 and 83 are mounted, and the variable magnification lens 84 system are placed at the home position (the first scanner is The second scanner is set at the start standby position, the second scanner is set at the 1x start position, and the lens system is set at the 1x position. The microprocessor 31 is
After completing this home position setting, processor 1
Send the [Scanner Home] signal to 1.

The processor 31 receives "magnification data" from the processor 11.
(7th byte in Figure 5), the second scanner (82°83) and the lens system 8 are placed in the position corresponding to the magnification data.
4 and upon completion sends a "scanner home" signal to processor 11.

When the processor 11 receives a copy start input using the start key on the operation board 28 and sends a "scanner start" signal to the processor 31, the processor 31 sends the first scanner (61, 83) 120/variable magnification [■m
/sec]. The second scanner (82, 83) scans at half the linear velocity in conjunction with the first scanner.

The microprocessor 31 measures the scanning distance of the first scanner from the scanning home position sensor (57) using a signal from a rotary encoder 59 coupled to a scanner driving DC motor 58, and determines the lead edge position (scanning start position of the original). ), it sends a "lead edge" signal to processor 11. The processor 11 counts the pulses of the drum encoder 25 starting from the point in time when it receives this lead edge signal, and controls sequences such as registration start, erase off, and bias switching. In other words, at the required timing,
On/off signals and setting data for the copy processing element are created and sent to the processor 31.

While the scanner is being scan-driven for exposure scanning as described above, when a "scanner return" signal (instruction to return the scanner to the home position) is transmitted from the processor 11, the processor 31 moves the scanner at that point. Stop and immediately return. From the processor 11 [
If the scanner reaches the maximum scan position before the ``scanner return'' signal is sent, processor 31 causes the scanner to return drive at that point and sends a ``scanner max'' signal to processor 11.

The processor 11 determines the rear end erase timing based on this timing.

Lens system driving (magnification setting) is performed by a lens driving stepping motor 54. That is, the lens 84 is moved to a position corresponding to the specified magnification, and the second scanner (
82, 83) to set the start position. The magnification is set by changing the distance between the document, the lens, and the drum, and the second scanner is positioned at a position corresponding to the magnification.

In this case, the microprocessor 31 calculates the target position of the lens 84 based on the "magnification data" transmitted from the microprocessor 11, selects lens drive (A-selector 42 of the output port PO of the input/output port), A rectangular wave with a phase shift of π/2 is output to the output port PA to the selector 42, ~3, and the position of the variable magnification lens 84 is controlled in the bidirectional (forward/reverse: enlargement/reduction) direction.

The positioning of the lens 84 corresponding to the specified magnification is performed by the stepping motor 5 after the lens home position sensor 53, which is set at the same magnification position, detects the same magnification position.
The energization of the motor 54 is stopped when the number of energizing pulses 4 reaches a value corresponding to the specified magnification.

The driving speed of the stepping motor 54 is determined by the processor 31.
The speed is controlled to 1 sopps by an internal timer interrupt.

FIG. 12b shows a drive system for the lens 84.

The second scanner (mirror 82, 83) system is different from the original (78) and photoreceptor drum 87 during reduction and enlargement, compared to the same magnification.
In order to increase the distance between the lenses, the stepping motor 56 is used to perform position control in the same manner as the lens 84. The control method is to output a rectangular wave to PA, 7, as in the lens 84 system. In this case as well, the same magnification position is set as the second scanner home position 55.

Further, the driving of the two stepping motors 54 and 56 is started at the same time and is controlled until each movement is completed.

The first scanner (61, 83) and the second scanner (82)
, 83) is shown in FIG. 12c.

A servo motor 58 is used as the scanner motor to control the speed when changing the magnification.

Scanner drive control is performed by transmitting pulse signals from a rotary encoder 59 attached to a scanner motor 58 to a processor 3.
PWM control that counts with the internal counter 1, calculates the scanner speed, performs PI (proportional integral) calculation based on the difference from the target value, and controls the ON time of the H-type transistor array (motor driver) using the programmable timer 33. The calculations from speed calculation to PWM output described above are shown in block form in FIG. 12d.

Detection of scanner movement direction, i.e. scanner motor 58
To detect the rotation direction, a flip-flop 41 detects the phase difference between outputs A and B of a rotary encoder 59 directly connected to the motor 58, and the processor 1 determines this based on the level of the input port PC3. Further, other optical control human output signals and port assignments are shown in FIG. 12e.

Scanner speed calculation and scanner position detection are performed in response to the arrival of encoder pulse A as is at interrupt input terminal CI. Exposure scanning position detection is performed for scanner address processing such as lead edge timing signals based on the number of interrupts, and scanner speed calculation is performed by adjusting the interval of encoder (5o) interrupts to the clock 012 (1) inside the processor 31. , 2μ5ec) with an ECNT (timer event counter).

The speed of the first scanner is expressed by the following equation. However, the number of pulses generated by the encoder 59 for one rotation of the motor 58 is 400 pulses.

Further, when the scanner returns, the frequency divider 40 is turned on by the output of the output port PC4, and speed 9 position control is performed by interrupting the encoder pulse whose frequency is divided by 1/4.

The optical system control in step 13 of the main routine shown in FIG. 7a includes the optical system control main routine shown in FIG. 11a, the timer interrupt for variable magnification lens/mirror position control shown in FIG. This is performed using the encoder 59 pulse interrupt for exposure scan control shown in FIG.

Exposure scanning is started by the optical system control (13), and while the scanner motor 58 is being driven, an encoder interrupt (Fig. 11c) occurs, and with this encoder interrupt (Fig. 1ie), a calculation request is set (153), After passing through this encoder interrupt, the 11th
Returning to the main routine in figure a, the process proceeds to steps 73 to 76, where the speed data stored in step 153 (
Perform speed calculation (74) from ECPT), calculate the difference with the target speed that matches the magnification ratio, and perform PI (proportional integral) calculation (75).
) to output PWM (76). Note that the calculation request flag is set to the encoder interrupt (Figure 1ie) as described above.
It is set during (153), and reset after the scanner speed calculation is completed (76).

If an abnormality occurs in the optical system (motor, encoder, home position sensor), execute the abnormality processing (off setting and transmission near 8 to the processor 11), set the abnormality flag (79), and then change the magnification. Normal control of the exposure scanning system is not included.

The main routine (11th
In Fig. a), the process branches in steps 81 to 94, respectively.

The scanner return routine (85)
1 or when the scanner reaches its maximum address (limit position), this routine (85) sets the target speed at return and sets the encoder division by 174. Start speed control by

When you proceed to this scanner return, (SCTST
) is set to 9 (SCAN9), and steps 162 and 163 are executed at the encoder interrupt.

The scanner homing routine (87) starts when the power is initially turned on, and rotates the scanner motor (58) in the normal direction (11th c.
155 in the figure. After 156:5CAN1), start the reverse and encoder interrupt (157 to 159 in Figure 11c)
: Controlled by 5CAN2), the scanner is initially placed in the fixed position (scanner home position).
to stop. In addition, if the home position is not detected, reverse rotation control (steps 157 to 159: 5
CAN2) only.

The Lens and Mirror Homing Routine (89) follows Scanner Homing (87) at power-up or
Activated when "magnification data" is received, the scanner target speed is calculated according to the specified magnification, and the stepping motors 54 and 56 for driving the variable magnification lens and mirror are started. , control is performed until the movement is completed.

When the power is on, the magnification is set to the same magnification data, and both the variable power lens and mirror are set to the home position.

The scanner start routine (91) is activated upon reception of a "start" request from the microprocessor 11,
The forward rotation of the scanner motor 58 is started. In addition, the scanner status is set to 3 (SCAN3), and the scanner speed is controlled and the scanner position information is detected (160,
161).

The scanner free run routine (93)
The scanner starts when it receives the "scanner test mode" from 1, calculates the target speed of the scanner according to the magnification data instructed by the processor 11, and starts forward rotation of the scanner motor. After that, encoder interrupt (Figure 11c: INT
20H) No5 CAN II free run routine (166
) to repeat the start/return using the optical system alone.

The internal timer interrupt (Figure 11b: lNT18) 1) is
When the power is turned on and when a magnification change request is made from the processor 11, that is, when the "magnification data" is other than 100, the mask is canceled in the lens/mirror homing process (89), and 15
Start an event timer of 0PPS (6,6m5ec/pu1g). Every time this timer times out, it is determined whether the stepping motor energizing pulse number count value has reached the number corresponding to the variable magnification data from the processor 11 (no completion of magnification position driving). Then, the event timer is restarted by incrementing the count by one and energizing the stepping motor by one unit pulse.

In other words, 1. The amount of movement of the lens 84 and mirrors 82, 83 from the home position is determined by the stepping motor 54,
Tracking is performed by counting 56 energizing pulses, and control is terminated when the count value reaches a value corresponding to the specified magnification.

The encoder interrupt (Fig. 11c) is divided by the mask every time during scanner homing (87), forward rotation and reverse rotation of the scanner, and performs scanner speed control and scanner address (exposure scanning position) detection, and the latter is used for document scanning. When the starting point and the limit position are reached, the processor 11
Send the "read edge timing" and "maximum scanner address" to

Encoder interrupt (pulse A of encoder 59 changes from 1 to 0)
) occurs, the watchdog timer 1 is reset. This is a time interval setting for abnormality detection when an encoder pulse does not occur due to an abnormality in the motor 58 or encoder 59 within a certain period of time. It is. That is, if an encoder interrupt does not occur within the time set by the watchdog timer 1, it is determined that the motor 58 and/or the encoder 59, or the mechanical system (scanning system) connected thereto, is abnormal.

Since the number of encoder pulses from the home position is used as the scanner address, each encoder interrupt counts up (increments) by 1 for forward rotation and counts down (decrements) by 1 for reverse rotation. During scanner speed control, at startup (scanner start and return start), the time from the timer start timing to the first encoder interrupt is undefined (speed is low at drive start-up)
Therefore, storage and calculation requests for speed (ECPI) are not performed. Therefore, the FIR5T flag is reset at the start of scanner start and return start. Thereafter, in the second and subsequent encoder pulse interrupts, time data (ECPT) of the interrupt intervals are stored and a calculation request is generated to perform PI sub-control.

According to the request from the microprocessor 11 and the scanner mode setting (SCTST) in the microprocessor 31, the scanner homing forward/reverse rotation, scanner start (scanning), scanner return, home position, and free run are controlled as described above. .

The microprocessor 11 of the system control circuit board 10 includes:
Immediately after initialization after turning on the power, when there is a key shake on the operation board 28 and the copying conditions are set or changed, or when there is a start input, the timing to switch the on/off state of each load, and the load state. Alternatively, at the timing of referring to the sensor detection state, the transmission data shown in FIG. 5 is set and transmitted to the microprocessor 31 of the I10 control circuit board 30. When this transmission occurs, the processor 31 reads the transmission data at the reception interrupt shown in FIG. 7b, and subsequently transmits the data shown in FIG. 6 to the processor 11.

(Effects) As described above, the control device of the present invention is electrically connected to the operation board 28 having keys for input operation by the operator and the photoreceptor rotation synchronization pulse generation means 25,
8, the second microprocessor 31 inputs a scanning speed target value, a variable lens/mirror position target value, a lamp voltage target value, and a developing bias voltage target value.
and in response to the operation of the start key on the operation board 28, serially communicates a load on/off instruction signal and a scanning means start/return instruction signal connected to the second microprocessor 31 in a predetermined sequence. photoreceptor drive energizing means 60 for electrically energizing the first microprocessor 11 and the photoreceptor drive means 64 for rotationally driving the photoreceptor 87; charge energizing means 49 that electrically energizes the charging means for charging; an exposure lamp 61 that illuminates the image of the original on the original table 78; [Exposure mirrors 81, 82, 83, 85 degrees that project the reflected light from the document onto the surface of the photoreceptor; Variable magnification lens 84 and mirror 8 that adjust the magnification of the image projected onto the surface of the photoreceptor.
variable magnification exposure scanning energizing means for energizing each electric element of the variable magnification exposure scanning means, which is comprised of scanning means 58 for scanning an image on the document by relatively scanning one of the document and the exposure mirror 81; ; development biasing means 51 that electrically biases the developing device that visualizes the exposed surface of the photoconductor 87 ; transfer biasing unit 4 that electrically biases the transfer device that transfers the developed image of the photoconductor 87 onto recording paper;
9; Paper feeding biasing means 47 that electrically biases the paper feeding unit that supplies the recording paper to the transfer unit; and Fixing biasing unit 60 that electrically biases the fixing unit that heat-fixes the transferred recording paper; Also, exposure lamp voltage detection means 60; variable magnification lens;
Mirror position detection means 53, 55: electrically connected to exposure scanning position detection means 57; exposure scanning synchronization pulse generation means 59; development bias detection means 51; and fixing temperature detection means 60; The zoom lens/mirror is positioned at a position corresponding to a position target value, and in response to the on/off signal and start/return signal, the biasing means is instructed to turn on/off at a specified timing. , the exposure lamp is controlled at a constant voltage in accordance with the lamp voltage target value and the exposure lamp voltage detection value, the scanning speed is controlled at a constant speed in accordance with the scanning speed target value and the exposure scan synchronization pulse, and the developing bias voltage target value and a second microprocessor 31 that controls the developing bias at a constant voltage in accordance with the detected developing bias value, reads the detection state of the detection means at a predetermined timing, and supplies the detected state to the first microprocessor through serial communication; It consists of .

Conventionally, the number of microprocessors and ports has been simply increased in order to cope with the increase in the amount of control tasks and the number of input/outputs associated with the multifunctional demands of copiers, but this increases costs. Not only that, but communication control between microprocessors becomes complicated. In other words, it becomes extremely difficult to determine the tasks of each microprocessor, leading to bugs.

Furthermore, the time required for communication between microprocessors becomes longer, making it impossible to perform the original task.

The control device of the present invention is constructed as described above so that the second microprocessor 31 performs as many tasks as possible, so it is better than the conventional construction. Furthermore, if the main control unit, which is a brain, and the input/output control units, which are its arms and legs, are mounted on the same board as in the past, the arms and legs cannot move freely until the brain is completed, but in the present invention, As described above, this problem has been solved by separating sequence control and input/output control between the first microprocessor 11 and the second microprocessor 31. As a result, (1) the system configuration is simple and clear, the number of parts is small, and program design becomes easy; Furthermore, (2) since the first and second microprocessors 11 and 31 can each be operated independently, debugging is facilitated and the development period is shortened. Further, according to the present invention, there is substantially no wiring harness from the system control circuit board 10 equipped with the first microprocessor 11 around the operation board on the top surface of the copying machine to each copy processing element and the sensors therein. These are connected to a wire harness from the I10 control circuit board 3o on which the second microprocessor 31 is mounted, at the back of the copying mechanism. Therefore, there is virtually no wire harness from the top of the copying machine to the copying processing elements in each part of the copying machine, and the wire harness arrangement is simplified, shortened and highly efficient, and the work efficiency of assembling the control device into the copying machine is high. This reduces the cost of copying machines.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an outline of the configuration of the present invention. FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention in functional block form. FIG. 3 shows a system control circuit board 1 according to an embodiment of the present invention.
FIG. 4 is a block diagram showing the actual electrical elements on the I10 control circuit board 30. FIG. FIG. 5 is a plan view showing the contents of one frame of data transmitted from the microprocessor 11 on the system control circuit board 10 to the microprocessor 31 on the I10 control circuit board 30, and FIG. FIG. 3 is a plan view showing the contents of one frame of data transmitted from the microprocessor 31 to the microprocessor 11 on the system control circuit board 1O. FIG. 7a is a flowchart showing an overview of the control operation of the microprocessor 31, and FIG. 7b is a flowchart showing an overview of the control operation of the microprocessor 1.
7c is a flowchart showing the microprocessor 31's interrupt processing operation in response to a zero-crossing pulse; FIG. 7d is a flowchart showing the microprocessor 31's interrupt processing operation in response to a zero-crossing pulse. , is a flowchart showing an internal timer interrupt processing operation. 8 is a flowchart showing an overview of the heater control operation of the microprocessor 31, FIG. 9 is a flowchart showing the developing bias control operation of the microprocessor 31, and FIG. 10a is a flowchart showing the exposure lamp energization control operation of the microprocessor 31. The flowchart shown in FIG. 10b is a time chart showing the relationship between the AC power supply voltage, its zero-cross pulse, and the lamp applied voltage brought about by the exposure lamp energization control operation of the microprocessor 31. FIG. 11a is a flowchart showing the control operation of the variable magnification exposure scanning system by the microprocessor 31, FIG. 11b is a flowchart showing timer interrupt control executed in this control operation, and FIG. 1IE is a flowchart showing the encoder executed in this control operation. 3 is a flowchart showing a pulse response interrupt processing operation. FIG. 12a is a side view schematically showing the mechanical structure of the variable magnification exposure scanning system, FIG. 12b is a perspective view schematically showing the mechanical structure of the variable magnification lens drive system of the variable magnification exposure scanning system, and FIG. 12c is a schematic diagram showing the mechanical structure of the variable magnification exposure scanning system. A perspective view showing an overview of the mechanical structure of the scanning system of the variable magnification exposure scanning system;
FIG. 12d is a block diagram showing the details of scanning speed control of the microprocessor 31 in functional blocks, and FIG. 12e is a block diagram showing the details of scanning speed control of the microprocessor 31.
7 is a time chart showing the waveforms of the encoder output of the variable magnification exposure scanning system, the energizing signals of the variable magnification lens drive motor and the variable magnification mirror drive motor, and the home position detection signal. 10 System control circuit board 11: Microprocessor (first microprocessor) 12: ROM l3: RAM
14 Near real communication unit 15 Near address decoder 16: Address latch 17: I/O port 18
: Gate 19: Toner concentration sensor 20
: Power-on reset circuit 21: AND gate 22, 23: NAND gate 24: Counter 25 Nidram encoder 26: Buzzer 27: Display 28: Operation board 29: Eraser 30: Input/output control circuit 31: Microprocessor (second microprocessor) ) 32: ROM 33: Timer 34 Near address decoder 35 Near address latch 3
6.37: Input/output port 38, 39: Gate 40:
Frequency divider 41: Flip-flop for direction determination 42: Data selector 43: Puffer amplifier 44: Power-on reset circuit 45: Paper feed sensor 46: Paper feed clutch 47
: Registration roller clutch 48 : Paper sensor 49 : Charger voltage circuit 50 : Static elimination LED 51 : T! A image device 52: Red erase solenoid 53: Lenses H, P,
Sensor 54: Lens drive motor 55: Mirror H,
P, sensor 56: Mirror drive motor 57: Scanner H, P, sensor 58: Scanner drive motor 59:
Scanner encoder 60: AC driver 61
: Exposure lamp 62. 63: Fixing heater 64: Main motor 65: Fan motor 66: Corona voltage control grid 167: Original density sensor 68: J
i'! Document size sensor 69: auto feeder 7
0: Editor 71: Information addition device i! 72
:Test monitor 73:Sorter 74:Double-sided processing unit 75:Composition processing unit 76:Key card unit 77:Test monitor 78:
Contact glass plate 79: Optical fiber 80
: Reflector plate 81 to 83. 85: Mirror (82, 83: Variable magnification mirror) 84: Variable magnification lens 86: Dust-proof glass 87: Photosensitive drum 88: Lens housing 89: Wire 90: Boule 91: Gear

Claims (1)

[Scope of Claims] It is electrically connected to an operation board having keys for input operation by an operator; and a photoreceptor rotation synchronization pulse generating means; The lens/mirror position target value for zooming, the lamp voltage target value, and the developing bias voltage target value are given to the second microprocessor below, and in response to the operation of the start key on the operation board, the following second microprocessor is executed in a predetermined sequence. applying an on/off instruction signal of the means connected to the second microprocessor and a start/return instruction signal of the scanning means to the second microprocessor through serial communication;
a first microprocessor; a photoreceptor driving and energizing means for electrically energizing a photoreceptor driving means for rotationally driving the photoreceptor; a charging energizing means for electrically energizing a charging means for charging the surface of the photoreceptor; an exposure lamp that illuminates the image of the original on the original table; an exposure mirror that projects the reflected light from the original onto the surface of the photoreceptor; a variable magnification lens/mirror that adjusts the magnification of the image projected onto the surface of the photoreceptor; and the original and exposure mirror. Variable magnification exposure scanning energizing means that energizes each electric element of the variable magnification exposure scanning means, which is a scanning means that scans the image on the document by relatively scanning one side of the image; Development energizing means that electrically energizes the developing means that transfers the developed image on the photoreceptor onto recording paper; A paper feed biasing device that biases; and a fixing bias device that electrically biases a fixing device that heat-fixes the transferred recording paper; and an exposure lamp voltage detection device; and a variable magnification lens/mirror position detection device. ; Exposure scanning position detection means; Exposure scanning synchronization pulse generation means; Development bias detection means; and Fixing temperature detection means; position the lenses and mirrors for
In response to the on/off signal and start/return signal, the energizing means is turned on/off at a specified timing.
The exposure lamp is controlled at a constant voltage in response to the lamp voltage target value and the exposure lamp voltage detection value, the scanning speed is controlled at a constant speed in response to the scanning speed target value and the exposure scan synchronization pulse, and the developing bias is A second microprocessor controls the developing bias at a constant voltage in accordance with the voltage target value and the detected developing bias value, reads the detection state of the detection means at a predetermined timing, and supplies the detection state to the first microprocessor through serial communication. A control device for a copying machine consisting of a processor.