JPH0243570A - Abnormality monitoring device for office equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to monitoring and controlling of office equipment such as copying machines, and particularly to monitoring and controlling when an abnormality occurs in office equipment equipped with digital control means such as a microcomputer.

[Prior Art] Many office equipment 9, such as copying machines, facsimile machines, printers, etc., are equipped with a microcomputer (hereinafter referred to as a CPU) as a control device. Especially recently, one device has three or more CPUs. It is not uncommon for some to have one.

Incidentally, in many devices of this type, various control objects are controlled based on the contents of a memory connected to a CPU. Specifically, in modern copying machines, for example, each voltage of a high voltage generation circuit that generates voltages applied to various dischargers is controlled by the pulse width of a control signal, and the control signal is transmitted to the memory. A pulse width is determined based on the stored value. In addition, in order to make it possible to change the voltage setting value, the memory that stores the setting value is a read/write memory whose memory content is made non-volatile by a battery, for example, and the memory content can be updated as necessary. There is.

[Problems to be Solved by the Invention] By the way, the contents of the read/write memory may be partially updated to erroneous values due to its own failure or the influence of external electrical noise.

This type of malfunction does not affect the CPU operating program itself, so even if it occurs, it cannot be detected by conventional runaway detection or other means.

However, if, for example, the data that determines the set voltage of the high voltage generation circuit is rewritten due to a memory error, an abnormally high voltage will be output, causing leakage or dielectric breakdown, which may lead to serious equipment failure or accidents. Conceivable.

Therefore, in boat fishing, a method is used in which an upper limit and a lower limit are set for the value of a control parameter, and if the value deviates from the limit, it is regarded as abnormal. However, with such methods, if an abnormality occurs within the set control parameter limit values,
It is not possible to detect the occurrence of an abnormality, and it is impossible to identify the cause of the deterioration in device performance (for example, copy quality) that occurs in such a case.

SUMMARY OF THE INVENTION An object of the present invention is to provide an abnormality monitoring device for office equipment that can reliably detect abnormalities in the contents of memory in a digital control device.

[Means to solve the problem] In order to achieve the above object, in the present invention.

Control means; non-volatile first storage means connected to the control means and pre-stored in at least a portion thereof with predetermined identification information; controlled by the control means based on the information stored in the first storage means; a controlled object; and at least a portion thereof.

non-volatile second storage means in which the same information as the identification information stored in the first storage means is stored in advance; and the control means is controlled by the identification information stored in the first storage means. and the identification information stored in the second storage means, and if the comparison results are different, the presence of an abnormality is identified.

[Operation] In other words, the same identification information is written in advance into two mutually independent memories, and when the identification information in these two memories is compared and a difference occurs in the comparison results, it is determined that there is an abnormality. According to this, if even one bit of incorrect information is written in the identification information of one memory,
It can be immediately detected as an abnormality.

In a preferred embodiment of the present invention described below, a plurality of C
A PU is provided, and the same identification information is written in a memory connected to each CPU, data is transmitted between the CPUs, and two sets of identification information are compared. Further, the identification information is compared immediately after the power is turned on, and if there is no abnormality, it is used as the initial value of the control parameter.

According to this, the amount of information provided for abnormality identification can be minimized, and the memory capacity required for this can be reduced.

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

[Embodiment] FIG. 2 shows one type of copying machine embodying the present invention. This will be explained with reference to FIG. Briefly speaking, this copying machine consists of a copying machine body, an ADF (automatic document feeder) 60.
Sorter 70. It is composed of a group of optional units such as an automatic double-sided processing unit 80. The paper feed system that supplies recording sheets has five stages. That is, the first paper feeding system and the second paper feeding system are provided in the main body of the copying machine, and the second paper feeding unit 170, which is the third paper feeding system, and the third paper feeding system, which includes the fourth paper feeding system and the fifth paper feeding system, 3 paper feed unit 180 is connected to the main body of the copying machine. 21, 22, 23 and 24 are the first paper feeding system, respectively;
These are cassettes provided in the second paper feeding system, the third paper feeding system, and the fourth paper feeding system, and 25 is a tray of the fifth paper feeding system.

A contact glass l on which a document is placed is provided at the top of the main body of the copying machine, and an optical scanning system 30 is provided below it. The optical scanning system 30 includes a W light lamp 31. First mirror 32. Third mirror 33° Fourth mirror 34. lens 3
5. A fifth mirror is provided with a 36° slit 37, etc. When performing document reading scanning, a first carriage equipped with an exposure lamp 31 and a first mirror 32, and a second carriage equipped with a third mirror 33 and a fourth mirror 34 are arranged so that the optical path length does not change. Mechanically scan-driven at a relative speed of 1. The lens 35 is a zoom lens, and its magnification can be changed by driving a motor.

Therefore, the light emitted from the exposure lamp 31 is transmitted to the first mirror 32.
．． Third mirror 33. Fourth mirror 34. Lens 35. Fifth
Through the mirror 36 and the slit 37, the photosensitive drum 2
imaged on top.

Around the photoreceptor drum 2, there are a main charger 3 and an eraser 4. Developing device5. Pre-transfer static elimination lamp 6, transfer charger 7, separation charger 8. It is equipped with a dangling unit 9, etc.

The image reproduction process will be briefly explained. The surface of the photosensitive drum 112 is uniformly charged to a predetermined high potential by the discharge of the main charger 3. The charge in the portion not used for image reproduction is erased by the eraser 4. When the charged surface of the photoreceptor drum 2 is irradiated with reflected light from a document, the potential of that portion changes (decreases) depending on the intensity of the irradiated light. The photosensitive drum 2 rotates in the direction shown by the arrow in the figure, and in synchronization with this, the optical scanning system 30 sequentially scans the document surface, so that the density (light reflectance) of the document image is reflected on the surface of the photosensitive drum 2 A potential distribution corresponding to the distribution, that is, an electrostatic latent image is formed.

When the portion on which the electrostatic latent image is formed passes near the developing device 5,
The toner in the developing device 5 is attracted to the surface of the photoreceptor 2 according to the potential distribution, thereby developing an electrostatic latent image, and a visible image corresponding to the electrostatic latent image is formed on the photoreceptor drum 2. Ru. On the other hand, in synchronization with the progress of the copying process, recording sheets are supplied from one of the five paper feeding systems selected. This recording sheet is fed through the registration roller 27 at a predetermined timing so as to overlap the surfaces of the photoreceptor drums 1 and 2.

Then, the transfer charger 7 transfers the visible image (toner image) on the photoreceptor drum 2 to the recording sheet side, and the separation charger 8 separates the recording sheet to which the visible image has been transferred from the photoreceptor drum 2. do. The separated recording sheet is conveyed to a fixing device 12 by a conveyor belt 11. After passing through the fixing device 12, the toner image on the recording sheet is fixed onto the recording sheet by heat within the fixing device 12. The recording sheet that has been fixed is discharged to the sorter 70 or the automatic duplex unit 80 through a predetermined paper discharge path.

FIG. 3 shows the appearance of the operation board arranged on the top surface of the main body of the copying machine shown in FIG. Referring to FIG. 3, this operation board has a large number of key switches Kl.

K2. 3. 4a, 4b, 5. 6a.

K6b, 7. 8. 9a, 9b, 9c.

KIO, Kl l, 12a, 12b, 13°KC
, KS, KI Kl and KT and a number of indicators Di, D
2. D3. D4. D5. Equipped with LED etc.

FIG. 1 schematically shows the configuration of a control system 11 of the copying machine shown in FIG. 2. As shown in FIG. Referring to FIG. 1, this control system generally consists of three units 100, 200 and 300. 100 is the main control board, 200
300 is an operation board, and 300 is an optical system control board.

Each independent microcomputer 110°210
and 310 are provided.

The microcomputer 210 of the operation board 200 has one display control circuit 230. Key switch matrix 240.
Lamp control circuit 250. It is connected to the heater control circuit 260, etc., and controls the display of the display unit 220 (indicators DI, D2', D3, D4, and D5 shown in FIG. 3), scans and reads the status of various key switches, and controls the exposure lamp. 3I, the temperature control of the heater provided in the fixing device 12, etc.

Microcomputer 310 of optical system control board 300
is RAM (read/write memory) 320. Motor control circuits 330, 340. It is connected to a driver 360, etc., and performs reciprocating scanning drive control of the optical scanning system 30, copy image magnification control, image erasure control, etc. Ml is an electric motor that drives the optical scanning system 30, and M2 is an electric motor that adjusts the magnification of the lens 35 of the optical system.

A battery is connected to the power supply circuit of the RAM 320, and the RAM 320 is configured to supply a storage content retention current and maintain the storage content even when the power to the copying machine is turned off.

The control elements of the copying machine other than those mentioned above, such as the main motor, paper feeding mechanism, conveyance mechanism, paper ejection mechanism, various image reproduction process elements, fans, various optional units, etc., are controlled by the microcomputer 110 of the main control board 100. Ru. Signals from the sensor group 130 provided in each part of the copying machine are applied to the microcomputer 110 via a signal processing circuit 180, respectively. Solenoid, clutch.

Loads such as fans are connected to the microcomputer 110 via a driver 190. The high voltage power supply unit 120 includes a main charger 3°, a transfer charger 7,
It is connected to the bias electrodes of the separation charger 8 and the developing device 5, and supplies a predetermined high voltage or current necessary for the image reproduction process to these electrodes at a predetermined timing.

In this embodiment, the high voltage power supply unit 120 adjusts the voltage or current value by pulse width control (PWM), and the signal that determines this pulse width is generated by the programmable timer (8251) 160.

A RAM (read/write memory) 150 equipped with a battery backup circuit is connected to the microcomputer 110 . This RAM 150 stores information on set values, such as numerical values that determine various voltages and currents generated by the high-voltage power supply unit 120, numerical values that set the light intensity of the exposure lamp, and numerical values that correspond to the set temperature of the fixing heater. .

Note that the same information stored in the RAM 1 50 is also stored in advance in the RAM 320 of the optical system control board. Of course, RAM 150 and RAM 32
Since 0 is writable, the microcomputers 110 and 310 can rewrite the information, respectively.

In addition, the microcomputer 110 of the main control board
is connected to the microcomputer 210 of the operation board and the microcomputer 310 of the optical system control board via a serial communication line so that information can be transmitted to each other.
′ connected with them.

That is, the serial signal transmitting boat TxD of the microcomputer 110 is connected to the serial signal receiving boat RxD of the microcomputer 310 via the gated buffer G1b and the buffer G3c, and the serial signal receiving boat RxD of the microcomputer 310 is connected via the gated buffer O1e and the buffer G2c. Serial signal receiving port R of the microcomputer 210
xD, and also microcomputer 1
The serial signal reception board hRxD of 10 is connected to the serial signal transmission board TxD of the microcomputer 310 via a gated buffer Glc and a buffer G3b, and is also connected to the microcomputer 210 via a gated buffer Glf and a buffer G2b. It is connected to serial signal transmission port TxD.

The output port SEL of the microcomputer 110 is connected to the gate terminals of the buffers yG1b, GLc, Gle, and Glf, and when SEL is at a high level I, the gates of the buffers Glb and G1c open and
When the gate of buffer f is closed and SEL is at a low level L, the gates of buffers Glb and Glc are closed and the gates of Ole and Glf are opened. That is, when SEL is H, communication between microcomputers 110 and 310 is enabled, and when SEL is L, communication between microcomputers 110 and 210 is enabled.

The main control board 100 includes a controller)-IC (7) that generates a reset signal when the device power is turned on and off.
705) 195 is provided. Reset ICI
No. 48 (RES ET ) outputted by the microcomputer 95 is applied to each reset terminal of the three microcomputers 110, 210, and 310. Therefore.

The microcomputers 110, 210, and 310 always perform a reset operation when the power is turned on/off.

In this embodiment, the microcomputer 110°210
and 310, 7811G manufactured by NEC Corporation is used. FIG. 4 shows an outline of the internal configuration of this microcomputer. Referring to FIG. 4, this microcomputer includes an oscillation circuit OSC, a serial I10 circuit Bl, an interrupt control circuit B2. Timer circuit B3. Timer/
Event counter circuit B4. A/D conversion circuit B5. Register B6. EPROM memory B7. It consists of a RAM memory B8 and various control blocks necessary for other processing.

The serial I10 circuit B1 has a serial data input terminal R.
A transmitting section includes three terminals: xD, serial data output terminal TxD, and serial clock input/output terminal SCK, as well as an 8-bit serial register, a buffer register, and a transmission/reception control circuit (not shown).

It consists of a receiving section and a mode register that specifies the operating mode. Note that the terminals RxD, TxD, and SCK are shared by the boats Pct, PCO, and PC2, respectively.

The transmitting buffer register generates an interrupt request INTST when internal data becomes empty, and the receiving buffer register generates an interrupt request signal INTSR when the internal data is fully stored.

The three microcomputers 110°210. in FIG.
The outline of the data transmission procedure performed between 310 and 310 is shown in
As shown in the figure. This will be explained with reference to FIG. In this embodiment, the microcomputer of the main control board 100 first initiates data transmission processing for the entire system, and then data transmission is repeated between the system microcomputers in a chain.

In other words, the microcomputer 110 first
If you set EL to high level ■] and send data,
The data is received by the microcomputer 310 of the optical system control board 300.
When 0 receives the data, it executes the interrupt processing described below in response to the interrupt request signal INTSR generated internally, processes the received data, and sends its own internal data to the main control board. The data is transmitted to the microcomputer 110 of. Upon receiving this data, the main control board microcomputer 110.

In response to the interrupt request signal INTSR, it executes an interrupt process to be described later, processes the received data, outputs L to the output port SEL, and then sends its own internal data to the microcomputer 210 of the operation board. Send to. When the microcomputer 210 receives the data, it executes an interrupt process to be described later in response to the 1 interrupt request signal INTSn, processes the received data, and
It sends its own internal data to the main control board's microcomputer 110.

By repeating the above operations, the main control board 10
0. Transmission and reception of data is repeatedly executed in order between the optical system control board 300 and the operation board 200.

The transmitted data is used to manage the control of the entire system, but is also used to detect data abnormalities in the memory.

The operation of the microcomputer on each control board will be explained below. 6a, 6b and 6c schematically show the operation of the microcomputer 110 of the main control board.

First, with reference to FIG. 6a, the microcomputer 110
Explain the operation. In step 1, initialization is performed. That is, the contents of the internal RAM of the microcomputer 110 are cleared, various modes are initialized, output ports are reset, and timers and interrupts are set. In addition, in order to start the communication operation, via the serial 110 circuit Bl,
One byte of data is sent to the microcomputer 310 of the optical system control board. Note that since data for storage is always stored in the RAM 150 connected to the microcomputer 110, it is not cleared.

In step l, when the microcomputer 110 transmits data and the microcomputer 310 of the optical system control board receives it, a reception interrupt request is generated to the microcomputer 310. Although not shown, when a reception interrupt request occurs, the microcomputer 310 processes one byte of received data and transmits its internal data one byte at a time to the microcomputer 110 on the main control board. The data transmitted by the microcomputer 310 usually includes information indicating the energizing state of the electric motors M1 and M2 and the position of the carriage of the optical scanning system.

When the data transmitted by the microcomputer 310 of the optical system control board is received by the main control board 100,
A reception interrupt request is generated in the microcomputer 110, and in response, the microcomputer 110
Execute the reception interrupt processing shown in the figure.

Referring to FIG. 6b, in step 21, the received data is processed and stored in the read/write memory B8 inside the microcomputer, and in step 22, the main control board 1
Send internal data of 00 to other control boards.

The transmission destination is alternately switched between the optical system control board and the operation board. That is, by switching the state of the output port SEL, when data is received from the optical system control board 300 in step 21, the data is transmitted to the operation board 200 in step 22, and the data is transmitted to the operation board 200 in step 21.
When data from 00 is received, the data is transmitted to the optical system control board 300 in step 22.

Although not shown, when the microcomputer 210 on the operation board receives data from the microcomputer 110, it executes interrupt processing in response to a reception interrupt request generated internally, and processes the received 1-byte data. At the same time, it sequentially transmits its internal data, ie, key manual information, exposure lamp status, fixing heater temperature, etc., one byte at a time to the microcomputer 110 of the main control board.

Therefore, as shown in FIG.
0, optical system control board 300, and main control board 1
00 and the operation board 200.

Data transmission and reception are performed alternately.

The data that the microcomputer 110 of the main control board sends to the operation board 200 includes the light intensity setting value of the exposure lamp, the setting temperature of the fixing heater, etc., but these data are stored in the RAM 150 of the main control board. is included, and the microcomputer 110 is R
AM 150 and send what is obtained.

Referring again to Figure 6a. Normally, RAM 320 of the optical system control board includes RAM 15 of the main control board.
0 (part of the setting value storage area) is stored, and in this state, the flag F set assigned to the remaining portion of the RAM 150 is set to 1.

In step 2, the state of this flag F set is identified, and if it is 1, proceed to step 3.

In step 3, a comparison information sending command is output to the optical system control board 300. Upon receiving this command, the microcomputer 310 of the optical system control board
320 and sequentially transmits the data to the main control board 100.

In step 5, the microcomputer 110 waits until it receives all the data in the RAM 320 output from the optical system control board 300. The received data is stored on the internal memory (B8) by the interrupt processing shown in FIG. 6b.

In step 6, each of the data on RAM 320 stored on the internal memory of microcomputer 110 is compared with the data on RAM 150, respectively. In this device, the addresses of each of RAM 150 and RAM 320 are as follows, except for a part (area for flags, etc.).
Since the same data are stored in advance and compared in °C, the comparison results in step 6 usually match completely.

However, for example, some memory cells in the RAM 150 may be defective, or the battery backup circuit may be malfunctioning.

Due to the influence of electrical noise, etc., the stored data may become RA.
There are cases where the value differs from M320 (in the case of abnormality occurrence). In this case, if even one bit changes, a difference will be detected in the comparison process of step 6, so it will be regarded as an abnormality, and the process will proceed to the abnormality processing routine shown in FIG. 6c.

Referring to FIG. 6C, in this abnormality processing, the software reset signal 5RES is first set to O. This signal 5RES is applied to the reset terminal of the microcomputer 310 via the OR gate G3a, and is also applied to the microcomputer 2 via the OR gate G2a.
Since it is applied to the reset terminal of 10, thereby,
Microcomputers 210 and 310 are held in a reset state. In the next step 32, all loads connected to the output of the microcomputer 110 are set to OFF.

Returning again to FIG. 6a, the explanation will be continued.

In step 7, the data in RAM 150 and the data in RAM 320 are
If the data is the same, it is normal, and the process then passes through step 8 and executes the main processing routine in step 9. That is, it performs various operations required for copy processing in the same way as a general copying machine.

For example, the voltages applied to the various corona dischargers (3, 7, 8) and the developing bias electrode are controlled on/off at predetermined timings that are synchronized with the progress of the copying process. That is, the microcomputer 110 applies an on/off control signal to the high voltage power supply unit 120 via the buffer 170 to control on/off of voltage application.

The value of the voltage applied to each corona discharger is stored in RAM 1
It is included in the setting data group stored in 50. This is executed by setting the setting data of each voltage in the timer 160. That is, the timer 160 generates pulse signals with widths corresponding to each setting data, and the output voltage of the high voltage power supply unit 120 is adjusted according to the pulse widths of these pulse signals.

Further, if there is an instruction to update (reset) the control parameters from the operation board 200 or the like, for example, the instruction is executed. That is,
After step 8, proceed to step 10 to clear the setting data set flag F set, and proceed to step 11. In step 11, various corona radiation Updates settings such as the voltage applied to electrical appliances, exposure lamp light intensity, and heater temperature. In other words, RAM150
The contents of those setting value memories assigned to respective predetermined addresses above are updated.

When this memory content is updated, main control board 1
00's RAM 150.

This will no longer match the data stored in the RAM 320 on the optical system control board. However, when the power is turned on again in this state, the flag F is set in step 2.

is cleared to 0, so step 4 is executed.

In step 4, the microcomputer 110
Sequentially reading out the data stored on the M150,
These data are sent to the optical system control board 300 along with a predetermined memory update command.

The data thus transmitted is written by the microcomputer 310 of the optical system control board into the RAM 320 on the optical system control board as update data.

Also, when this data is transmitted, the microcomputer 310 on the receiving side returns predetermined data to the main control board 100, but upon receiving the returned data, the microcomputer 110 as shown in FIG. Executes reception interrupt processing.

In that case, since the flag F set is cleared to 0, the process proceeds to step 24 after step 23 .

In the process of step 24, it is checked whether all the setting value data on the RAM 150 has been transmitted to the optical system control board 300. When all the transmissions are completed, step 25 is executed and the flag F set is set to 1.

When the flag F set becomes 1, the process of FIG. 6a proceeds to step 3-5-6, and as described above, the RA
The data of M150 and the data of RAM320 are compared.

[Effects] As described above, according to the present invention, if even a single bit error occurs in the data stored in the read/write memory, it is immediately detected as an abnormality, so the occurrence of an abnormality can be quickly and reliably known. It is possible to prevent abnormal operation of the device before it occurs.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an electrical component of the copying machine shown in FIG. 2. FIG. FIG. 2 is a front view showing the structure of a mechanical section of a copying machine of one type that implements the present invention. FIG. 3 is a plan view showing the appearance of an operation board provided in the copying machine shown in FIG. 2. FIG. FIG. 4 is a block diagram showing the internal configuration of each microcomputer shown in FIG. 1. FIG. 5 is a flowchart showing the procedure of data transmission between the plurality of control boards shown in FIG. 6a, 6b, and 6c are flowcharts outlining the operation of the microcomputer 110 of FIG. 1. FIG. 1: Contact glass 2: Photosensitive drum 4: Eraser 30: Optical scanning system 100: Main control board 110, 210, 310: Microcomputer (control means) 120: High voltage power supply unit 120, 250, 260: (Controlled object) 150 :R
AM (first storage means) 195: Reset IC 200: Operation board 220: Display unit 230: Display control circuit 240: Key switch matrix 250: Lamp control circuit 260: Heater control circuit 300: Optical system control board 320: RAM 2 storage means) 330.340: Motor control circuit Bl Nijirial I10 circuit B3: Timer circuit procedure correction heat (method) % formula % 1. Incident display 2. Name of the invention 3. Address related to the row incident to be corrected Name: 1986 Patent Application No. 193694 Abnormality Monitoring Device for Office Equipment

Claims (3)

[Claims] (1) Control means; Non-volatile first storage means connected to the control means and pre-stored in at least a portion thereof with predetermined identification information; The control based on the information stored in the first storage means. a controlled object controlled by the means; and a non-volatile second storage means in which at least a portion thereof stores in advance the same information as the identification information stored in the first storage means; , comparing the identification information stored in the first storage means with the identification information stored in the second storage means, and identifying the presence of an abnormality if the comparison result is different; abnormality monitoring of office equipment; Device. (2) The abnormality monitoring device for office equipment according to claim 1, wherein the control means controls the control target based on the value of identification information stored in the first storage means. . (3) Immediately after the power is turned on, the control means compares the identification information stored in the first storage means and the identification information stored in the second storage means, and if the comparison results are different; An abnormality monitoring device for office equipment according to claim 1, wherein the abnormality monitoring device for office equipment identifies whether there is an abnormality in the object, and sets the identification information as an initial value of a control parameter for the controlled object when there is no abnormality.