JPH0526937A - Image recorder - Google Patents

Abstract

PURPOSE:To enable loads and sensors connected to a control portion to be self-diagnosed individually with an easy and inexpensive circuit configuration and failure analysis when an abnormality occurs to be performed readily and positively and at the same time prevent a secondary abnormality from occurring by cutting off a power supply to a device main body. CONSTITUTION:A title item is provided with a control signal output means which supplies control signals to a plurality of targets to be controlled, a means 2 for detecting an amount of current which detects the amount of current which flows to the targets to be measured in response to a change in output of a control signal, a criterion means which judges normality/abnormality of the control signal output means 1 based on the amount of current which was detected, and a power supply control means 4 which cuts off a power supply to the device according to the criterion result by the criterion means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus such as a copying machine, a printer or a facsimile, and more particularly to an image recording apparatus capable of detecting an abnormality inside the apparatus (self-diagnosis).

[0002]

2. Description of the Related Art In recent years, an image recording apparatus such as a copying machine has come to be multifunctional, and various functions such as an automatic density adjustment and an automatic paper size selection function have been realized. Is coming.

[0003]

However, with such a movement, the inside of the apparatus becomes complicated, and it becomes difficult to investigate the cause when any abnormality occurs, and a simple and reliable self-diagnosis function is required.

In particular, in an image recording apparatus such as a copying machine, a plurality of electromagnetic solenoids and electromagnetic clutches for controlling the drive section, and a plurality of photo interrupters for detecting the position of the image recording paper are used. Therefore, it is expected that the connection of these elements to the control unit and the normal operation (or abnormality) of each component can be confirmed easily.

Therefore, an object of the present invention is to realize an easy and inexpensive self-diagnosis function without drastically changing the configuration of the image recording apparatus, monitor an abnormality in the apparatus, and investigate the cause when the abnormality occurs. An object of the present invention is to provide an image recording apparatus configured so that the above can be surely performed.

[0006]

In order to achieve such an object, the present invention provides a control signal output means for supplying a control signal to a plurality of controlled objects, and a control signal output means for responding to a change in the output of the control signal. A current amount detection means for detecting the amount of current flowing through the controlled object, a determination means for determining normality / abnormality of the control signal output means based on the detected current amount, and a determination by the determination means. According to the result, the power supply control means for shutting off the power supply to the apparatus is provided.

[0007]

According to the present invention, the control signal output is changed, and a predetermined amount of current is detected in synchronization with the change in the control signal output to determine whether the control signal output system is abnormal or normal. According to the result of the determination, the power of the device is shut off.

Further, in the preferred embodiment of the present invention, for the signal input from the sensors, for example, it is detected that the logic of the input signal is inverted in synchronization with the on / off of the power source of the signal generating source. To determine whether it is abnormal or normal.

As a result, an easy and inexpensive self-diagnosis function can be realized without requiring a complicated circuit.

[0010]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 shows the basic construction of an embodiment of the present invention. In this figure, 1 and 2 are solenoids,
A control signal output means and a current amount detection means for the clutch, motor, etc. 6. Further, 3 and 4 are signal input means and power output control means for the sensors 5 respectively. Reference numeral 7 is a power cutoff means for turning off the power switch (SW) 14.

FIG. 2 is a block diagram showing the details of each means 1 to 7 shown in FIG. FIG. 2 shows the control unit 20, the sensors 5, the clutch / solenoid 6 and the like.

Q1 is a transistor for supplying electric power to the sensors 5 and corresponds to the power supply output control means 4 in FIG. Further, R2 and R3 are pull-up resistors and limiting resistors for inputting signals from the sensors 5 and correspond to the signal input means 3 in FIG.

Q2 is a transistor for turning on / off the solenoid clutch 6 and corresponds to the control signal output means 1 of FIG.

Q3 is a transistor for turning off SW14 shown in FIG. 4. When Q3 is turned on, SW14 is turned off.
Corresponds to the power cutoff means 7.

All of the above four means become input / output signals of the interface IC (shown as "I / O" in the figure) in the control section 20. R1 is a resistor for detecting the amount of current flowing into the clutch / solenoid 6 and corresponds to the current amount detecting means 2 in FIG. The analog voltage detected from both ends of the resistor R1 is amplified by the amplifier circuit 7, the output voltage is A / D converted, and recognized by the CPU (not shown) in the control unit 20 as a digital value.

FIG. 3 shows the structure of the main body of the copying machine having a self-diagnosis function. In the figure, 13 is the copying machine main body, and 14
Is its power switch, 15 is a document table on which the document 6 is placed, 16
Is an image forming section, which is mainly composed of the photosensitive drum 17, and has a charger 18, a cleaner 19, an erase lamp 20, and the like. Numerals 21 and 22 are developing units containing red and black toners, and developing rollers 21a and 22a are provided respectively.

Reference numeral 23 is a paper feed unit for feeding the transfer papers SH ₁ and SH ₂ into the main body 13, and is composed of detachable cassettes 24 and 25 and their paper feed rollers 26 and 27. Reference numeral 28 denotes an optical system for exposing and scanning the original 6 by the exposure lamp 29 to form an image on the photosensitive drum 17, and has a lens system including a condenser lens 30.

31 is an optical motor for moving the optical system 28, 32
Is a fixing device having a fixing roller 33, 34 and 35 are heaters, 36 is a paper discharge tray, and 37 is an optical stand on which the condenser lens 30 is placed.

In addition, other 38 is a paper feed roller, 39 is a charger, 40 is a separation charger, 41 is a discharge roller, and 42 is a photosensitive drum.
Main motors for driving 17, 43 and 44 are pressurizing solenoids of the developing devices 21 and 22, and S _{1 to} S ₁₅ are optical sensors provided in the above parts. It is configured to output.

FIG. 4 is a control block diagram of the copying machine. In FIG. 4, reference numeral 45 is a control unit including a light emission changing unit and a document size detecting unit.

Although not shown, the control unit 45 is composed of a CPU and a ROM storing data for control, and controls the entire apparatus. In the figure, 46 is an AC power supply, 47 is a control unit 45.
DC power supply (DCP) to be supplied to the, etc., S is each sensor shown in FIG. 3, 48 is an operation unit, 49 is an AC driver that is an AC load control unit, and controls the AC load 50 such as lamps and heaters. To do.

Reference numeral 51 is a motor control section for controlling the optical motor 31 and the main motor 42, and 43 is a high voltage generator (HVT) which supplies high voltage to the charging devices 18, 39, 40 and the developing devices 21, 22. Reference numeral 53 is a load such as a solenoid, a clutch, and a fan.

Next, the operation of the above copying machine will be described.

When the power switch 14 is turned on, the heaters 34 and 35 in the fixing device 32 first generate heat and wait for the fixing roller 33 to reach a predetermined temperature at which fixing is possible. When the fixing roller 33 reaches a predetermined temperature, the main motor 42 is energized for a certain period of time to drive the photosensitive drum 17, the fixing device 32, etc., and the roller 33 in the fixing device 32 is driven.
To a uniform temperature.

After that, the main motor 42 is stopped and the apparatus stands by in the copy-enabled state. Here, the main motor 42 drives the photosensitive drum 17, the fixing device 32, the developing devices 21 and 22, and various transfer paper conveying rollers. Then, when a copy command is input from the operation unit 48, the copy operation starts.

In response to the copy command, the main motor 42 is rotated to rotate the photosensitive drum 17 in the arrow direction, and
A high voltage is supplied to the primary charger 18 from a high voltage generator 52, and a uniform charge is provided on the photosensitive drum 17. Next, the exposure lamp 6
Is turned on, the optical motor 31 is driven, and the document 6 placed on the document table 15 is exposed and scanned in the direction of the arrow and projected onto the photosensitive drum 17. As a result, an electrostatic latent image of the original 6 is formed on the photosensitive drum 17.

Then, this latent image is developed by the developing device 21 or 22, and is transferred by the transfer charging device 39 to the transfer paper SH ₁ or
It is transferred to SH ₂ and separated from the photosensitive drum 17 at the separation charger 40.

Next, after the residual toner remaining on the photosensitive drum 17 is collected by the cleaner 19 and uniformly erased by the erase lamp 20, the copy cycle is repeated again.

At this time, the first developing device 21 and the second developing device 22
One of them is brought into contact with the photosensitive drum 17 in response to a selection command from the operation section 48. For example, the first developing device 21 is charged with red toner to be a red developing device, and the second developing device 22 is A black developing device is prepared by inserting black toner.

Pressurization (contact) and release of these developing devices 21, 22 to and from the drum 17 are performed by respective solenoids 43 and 44. When the solenoid 43 is turned on, the red developing device 21 is released from the drum 17. When the solenoid 44 is turned on, the black developing device 22 is pressed against the drum 17. And each developing device 2
A black toner sensor S15 and a color toner sensor S6 are arranged in the insides of 1,22, respectively, and a developing bias voltage is applied from a high voltage generator 52 to the developing rollers 21a, 22a of the developing units 21,22. ..

Further, the optical system 28 is reciprocally controlled by rotating the main motor 42 forward and backward through the motor controller 51 according to a command from the controller 45. And the sensor
S1 is provided as a home position sensor of the optical system 28 and stops at this position during standby.

The sensor S2 is an image sensor corresponding to the leading edge position of the original image and is used for the timing of copy sequence control. The sensor S3 is a limiter position (reverse position) detection sensor at the time of maximum scanning. The optical system 28 is a control unit.
In response to a command from 45, it reciprocates with a scan length according to the cassette size and copy magnification.

Next, the operation of the operation unit 48 will be described.

FIG. 5 is an external view of the operation panel 100 of the operation unit 48. In the figure, 101 is a power switch for controlling energization to the copying machine main body, 102 is a zoom key for designating a magnification at an arbitrary magnification, for example, in 1% increments, 103 is a reduction key for instructing a standard reduction magnification, and 104 is a 1: 1 copy. A selection key, 105 is a magnification key for instructing standard magnification, 106 is a cassette selection key, and 107 is a copy density adjustment key.

Reference numeral 108 denotes a density correction key for changing the copy density designated by the copy density adjustment key 107. In this embodiment, the copy density is adjusted by controlling the lighting voltage of the exposure lamp 29 by the copy density adjustment key 107. The copy density is changed by changing the developing bias with the copy density correction key 108.

A clear / stop key 109 operates as a copy stop key during execution of the copy operation. 110 is a copy key, 111 is a residual heat key, 112 is a key for returning to the standard mode, 113 is a color selection key, and the keys 113 are used to switch the developing devices 21 and 22.

An asterisk key 114 is used to input the length of the original 6 and a desired length after copying, and a numerical key is used to select the magnification, and the number of copies is input by this key 115.

Reference numeral 116 is an AE key for designating an automatic density adjustment mode, 117 is a key for designating an automatic paper selection mode for selecting an optimum transfer paper according to a document size and a copy magnification, and 118 is a document size and a designated transfer. Key that specifies the automatic magnification selection mode that selects the optimum magnification according to the paper size,
Reference numeral 119 is a key for recalling the magnification set in the memory, 120 is a key for registering the magnification in the memory, 121 is a warning display indicating that there is no toner, no control counter, and a jam has occurred, 122 is an asterisk key, and 114 is magnification calculation. The LED that lights up when the operation is performed, and 123 is the LED that displays the specified standard magnification mode, which is specified by the keys 103 and 105.

Reference numeral 124 is an LED that indicates what cassette is used for copying, and 125 is an LED that displays the installed cassette. For example, A3 is installed in the upper row, A4 is installed in the lower row, and the lower row is selected. LED for cassette display is A
3, A4 lights up, and LED124 lights up A4. 127 is an LED that indicates which of the manual feed, upper row, and lower row is selected. 128 is an LED that lights when there is no paper in the cassette or no cassette is installed.
9 is an LED for displaying the number of copies, 130 is an LED for indicating the automatic density adjustment mode, 131 is an LED for density display, 132 is an LED for standby display, which lights in green when copying is possible and red when copying is not possible. ..

133 is an LE that displays the color of the designated developing device
D and 134 are indicators showing the automatic paper-sheet selection mode, and 135 is an LED showing the automatic magnification selection mode.

The toner-free display device 121a indicates whether or not there is toner in the developing device designated by the selection key 113 for switching the developing device. That is, when there is no black toner, it is turned on only when the black developing device 22 is selected, and is turned off when the color developing device 21 is selected. Conversely, the same applies when there is no color toner.

The operation of the self-diagnosis function described above is performed not only every time the power of the copying machine main body is turned on, but also on the operation panel 100. Code numbers are determined in advance for each of the solenoids, clutches 53, and sensors S, and a single item can be diagnosed on the operation panel 100. Further, on the operation panel 100, it is possible to automatically perform self-diagnosis for all of the solenoids / clutches 53 and the sensors S.

FIG. 6 is a flow chart showing an outline of the self-diagnosis operation for the clutch solenoids 53. First, in step 150, all of the clutch solenoids are turned off, and in step 151, the amount of current flowing out from the control unit 45 via R1 in FIG. 2 is measured, and the measured value is held as Iref.

At step 152, an initial value "0" is set to the variable N corresponding to each clutch solenoid, and at step 153 the load (clutch solenoid) corresponding to N is set.
Turn on the 53 output port.

At step 154, the amount of current in the ON state is measured, and at step 155, the difference from the previously measured Iref is calculated, and the result is the current value corresponding to the load 53 corresponding to the predetermined N. If it is Ip (N) or more, the process proceeds to step 156, and the variable N is incremented by +1 to measure the next load 53.
To do.

If the current value is less than or equal to Ip (N), step 157
Then, it is determined that the load 53 is abnormal, and the automatic diagnosis flow is stopped.

In step 158, it is confirmed whether or not the self-diagnosis is completed for all, and if it is not completed, the process returns to step 153 and the following flow is repeated.

FIG. 7 is a flow chart showing an outline of the self-diagnosis operation for the sensors S. First, step 16
At 0, the initial value 0 is set to the variable N corresponding to each of the sensors S, and at step 161, the transistor Q1 that supplies power to the sensors S from the control unit 45 is turned off.

In step 162, when the input from the sensor corresponding to N is at the "H" level, the process proceeds to step 163, and the variable N is incremented by 1 to perform the measurement corresponding to the next sensor. If it is not at "H" level, step 16
Proceed to 9 to stop the automatic diagnosis flow as a sensor error.

At step 164, it is confirmed whether or not the operations after step 162 have been completed for all the sensors, and if not completed, the process returns to step 162, and if completed, the process proceeds to step 165 and the variable N Is set to the initial value "0" (step 165), and the transistor Q1 is turned on (step
166), and confirm that the inputs from all the sensors are at the "L" level (steps 167 to 170).

When an abnormality is detected, the above-mentioned code number is displayed by blinking on the magnification display section 136 on the operation panel 100 for a certain period of time, and then the power cut-off means 7 shown in FIG.
SW14 is turned off, and power supply to the main body of the copying machine is cut off.

Further, during the copying operation, the control unit 45
Thus, the clutch, solenoid, fan, etc. are controlled according to the copy sequence, and at the same time, the amount of current flowing through the resistor R1 in FIG. 2 is monitored to confirm that the clutch, solenoid, fan is operating.

Next, another embodiment will be described.

In the above-described embodiment, the current detecting resistor R1 is used for measuring the current of the output port check. However, as another method, a Hall element is used to detect the current based on the Hall voltage or DC. It is also possible to detect the current by integrating the PWM signal that controls the output of the power supply.

The self-diagnosis based on the input / output port check is performed every time the power of the apparatus is turned on in the above-described embodiment. However, the self-diagnosis is automatically performed at a certain fixed time interval (for each time or the number of copies). It is also possible to carry out by key input from the department.

Furthermore, when the input signals from the sensors change depending on the state of the controllable load (clutch, solenoid, motor, etc.), those loads are controlled during the automatic diagnosis of the sensors to make a determination. You may go.

[0058]

As described above, according to the present invention,
With an easy and inexpensive circuit configuration, it becomes possible to individually diagnose the loads and sensors connected to the control unit.
When an abnormality occurs, the failure analysis can be surely performed at an early stage, and the secondary abnormality can be prevented by cutting off the power supply to the apparatus main body.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of an embodiment of the present invention having a self-diagnosis function.

FIG. 2 is a block diagram showing FIG. 1 more specifically.

FIG. 3 is a configuration diagram of a copying machine main body equipped with a self-diagnosis function.

FIG. 4 is a block diagram showing an electrical configuration of FIG.

FIG. 5 is an external view of an operation panel.

FIG. 6 is a flowchart showing a self-diagnosis operation.

FIG. 7 is a flowchart showing a self-diagnosis operation.

[Explanation of symbols]

 1 control signal output means 2 current amount detection means 3 signal input means 4 power supply output control means 7 power supply cutoff means 13 copying machine main body 14 power supply switch 45 control section 48 operation section 100 operation panel

Claims (1)

Claim: What is claimed is: 1. A control signal output means for supplying a control signal to a plurality of controlled objects, and an amount of current flowing through the controlled objects in response to a change in the output of the control signal. A current amount detecting means for detecting a current level, a determining means for determining normality / abnormality of the control signal output means based on the detected current amount, and a power source for shutting off power to the device based on the determination result of the determining means. An image recording apparatus comprising: a control unit.