JPH0486676A - High voltage output controller for electrostatic recorder - Google Patents

Abstract

PURPOSE:To improve the quality of a copy picture and to prevent the occurrence of an accident by providing an automatic adjusting function and constituting this controller in such a manner that an abnormality mode is outputted to an operation display part when the difference between the actual adjusted value after an automatic adjustment and the normal set-value is greater than the prescribed value. CONSTITUTION:The controller is provided with the automatic adjusting function so that the optimum high voltage is supplied to an electrifying means 11 and a developing sleeve by the use of a commanding value from a control part 100 and a copy picture with stable quality is obtained. When the difference between the altered set-value after automatic adjustment and the normal set- value is abnormally large, the abnormality code is displayed on the operation display part 104. Thus, the output current of the electrifying means, which is changed with variations in the assembly of the electrostatic recorder, etc., is automatically adjusted to the optimum current, the optimum voltage is applied, and a copy picture with excellent quality can be obtained; additionally, the occurrence of an accident can be prevented.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention is directed to high-voltage output control of an electrostatic recording device, such as an electrophotographic copying machine, which is equipped with a plurality of chargers for forming an image on an image carrier. Regarding equipment.

[Background of the invention]

In an electrostatic recording device, an image frame is formed by irradiating the peripheral edge of a rotating image carrier using a charging device such as a corona charger, an exposure device that projects a light image to form a latent image, and an LED. developing means for developing the latent image portion to form a toner image; charging means for transferring the toner image onto recording paper; and separation for separating the recording paper onto which the toner image has been transferred from the image carrier. A cleaning means for removing toner remaining on the image bearing member after transfer is provided.

The charging means, such as the charging means, the transfer means, and the separation means, use electrodes that perform high-voltage corona discharge.

This electrode and the developing sleeve of the developing means require a high-voltage power source that supplies high-voltage power.
There is a technique disclosed in Publication No. 79366 and the like.

Conventionally, the output current of the high-voltage power supply has generally been controlled to be constant regardless of the input voltage and load.

However, the optimal voltage conditions applied by the electrodes and the developing sleeve are not always constant, and the optimal conditions vary depending on the thickness of the paper, the front and back sides of the paper in the case of double-sided copying, humidity, etc.

In addition, regarding the electrodes, there are variations depending on the assembly, etc., and it is not always possible to obtain good results even if the optimal setting conditions for a standard recording device are replaced with another recording device. Since the charging potential has increased beyond the appropriate value, there have been problems in that the recording density is too high, causing background smudges, and white spots due to poor transfer separation, resulting in defective copied images.

Furthermore, if the set values changed to correct the variations are far apart from the standard set values, a defect that may lead to an accident may occur. However, there is a problem in that if this is not reported, the operator may continue to use the system without knowing it, leading to a serious accident.

[Purpose of the invention]

The present invention solves the above problems and has an automatic adjustment function to supply an optimal high voltage to the charging means and the developing sleeve to obtain stable copy image quality, and also has an automatic adjustment function that allows changes in setting values after automatic adjustment. An object of the present invention is to provide a high-voltage output control device for an electrostatic recording device that displays an abnormality code on an operation display unit when the difference is abnormally large from a standard setting value.

[Means to achieve the purpose]

The purpose is to provide a high-voltage power supply whose high-voltage output value is controlled by a command value from a control section, a means for feeding back the applied high-voltage output value to the control section, a ROM that stores standard setting values, and a ROM that stores actual adjustment values. This is a high-voltage output control device for an electrostatic recording device that is equipped with a non-volatile RAM for storage and has an automatic adjustment function, and if the actual adjustment value after automatic adjustment differs from the standard setting value by more than the specified value, an error code will be issued. This is achieved by a high-voltage output control device for an electrostatic recording device, which is configured to output the following information to an operation display section.

〔Example〕

FIG. 1 is a block diagram showing components near a photosensitive drum and connections between them and an electric circuit in an example of an electrostatic recording apparatus equipped with the apparatus of the present invention.

In the figure, reference numeral 10 denotes a photosensitive drum which is an image bearing member that rotates in the direction of the arrow (clockwise), and a charger 11 which is a charging means is attached to the peripheral edge of the drum. Static eliminator 12, developer 30, transfer device 13,
A separator 14, a cleaning device 50, etc. are provided.

100 is a control unit that performs copy process control and high voltage output control of the high voltage power supply unit 130; 101 is a ROM that stores a plurality of standard setting values V (N) and specified values SV according to various conditions to be described later; and 102 is an actual adjustment unit. A nonvolatile RAM that stores correction coefficients RV, etc., obtained by dividing the actual adjustment value by the standard setting value V (N), 103 is a numeric keypad, and other buttons, and it can send copy start commands, number of copies, automatic adjustment mode commands, etc. An operation section 104 inputs input to the control section 100; an operation display section 104 displays operation displays as well as the type and location of the abnormal state;
0 (130A to 130D) is a high voltage power supply section that supplies a constant current and high voltage to the electrodes of the charger IL transfer device 13, the separator 14, etc., and the developing sleeve 31 under the control of the control section 100.

Next, the basic operation of the copy process of this embodiment will be explained. A copy start command is sent from the operation unit 103 to the control unit lOO.
When the photoreceptor drum 10 is sent out, the photoreceptor drum 10 starts rotating in the direction of the arrow under the control of the control section 100.

As the photoreceptor drum 10 rotates, its circumferential surface charges the charger 11.
It is uniformly charged and passes through the static eliminator 12. Static eliminator 1
2, under the control of the control unit 100, the frame portion outside the image area is irradiated with, for example, an LED to eliminate static electricity. An image is written on the photosensitive drum 10 by projection light from a scanning optical system or an image writing device (not shown), and an electrostatic latent image corresponding to the image is formed.

There is a two-component developer in the developing device 30, which is stirred by the stirring screws 33A and 33B, and then transferred to a magnet.
7 A developing sleeve 3 that is located outside the troller 32 and rotates.
A magnetic brush of the developer is formed by adhering to the outer periphery of the developing sleeve 31, and a predetermined bias voltage supplied from the high-voltage power supply section 130D is applied to the developing sleeve 31, and development is performed in the developing area facing the photoreceptor drum 10. be exposed.

That is, the electrostatic latent image on the photoreceptor drum 10 is
0 to form a visible toner image.

Recording paper P is fed out one by one from the paper feed cassette 60 by the first paper feed roller 15. This fed-out recording paper P is sent onto the photoreceptor drum 10 via the guide path 63 by the second paper feed roller 16 which operates in synchronization with the toner image on the photoreceptor drum IO. and transfer device 13
Due to this action, the toner image on the photoreceptor drum IO is transferred onto the recording paper P, and is separated from the photoreceptor drum 10 by the separator 14. The recording paper P onto which the +toner image has been transferred is sent to a fixing device (not shown) via a conveying means 80, and is fused and fixed by a heat fixing roller and a pressure roller, and then discharged from the device. The surface of the photosensitive drum 10, which rotates with toner remaining without being transferred to the recording paper P, is exposed to the blade 5.
It is scraped off and cleaned by a cleaning device 50 equipped with a cleaning device 50, etc., and is ready for the next copying.

Next, the automatic adjustment function of the high voltage output control device of the present invention will be explained by taking as an example the high voltage output control of the high voltage supplied to the charger 11.

FIG. 2 is a block diagram showing the high voltage output control device of the present invention. In the figure, the high voltage power supply section 130 includes a DC/DC converter 131. Current detection unit 132. It consists of a converter 133, DC/DC: +7 converter 131, for example 2.2
When a command value V0(N) of V, 2 V, or 1.5 V is input, in the case of a standard device, the output current at the charger 11 is converted to a high voltage of 600 μA, 500 μA, or 300 μA, and the current is detected. Charger 11 through section 132
Supplies high voltage to the electrodes. The current detection unit 132 detects this output current, and the detected voltage is converted by the conversion unit 133 into a voltage value that corresponds inversely to the relationship between the standard setting value V (N) and the output current in the case of the standard device. , Nth feedback value V
5(N) to the control unit lOO.

The ROM 101 stores a standard setting value V (N) corresponding to the desired output current of the high voltage power supply section 130, for example, 2-2V for output current 600μu, 2.2V for output current 600μA, 2.
A plurality of standard setting values V (N) such as OV, 1.5V for 300 μA, and a specified value SV which is a value that defines the permissible range of the difference from 1 of the correction coefficient RV.
(for example, li)% (0, 1) is stored.

Next, high voltage output control in high voltage automatic adjustment mode (power supply section 13
0 automatic adjustment of the output current) will be explained based on the flowchart of FIG.

First, in step 1, the operation unit 103 uses, for example, a numeric keypad to input a signal for automatic adjustment mode input, which is unknown to general operators, and a standard setting value V suitable for the usage condition of the device.
Emit a signal specifying (N).

Then, the control section 100 enters the automatic adjustment mode of the high voltage power supply section 130, and the specified standard setting value V (N) is called from the ROM 1O1 to the control section 100.

Next, in step 2, the control unit 100 stores the ROM 101
The specified standard setting value V (N) (for example, 2V) is called and sent to the DC/DC converter 131 of the high voltage power supply unit 130 as the primary command value V 0 (1).

The high voltage electrode section 130 receives the primary command value VO (1) as described above.
(2V) is converted into a high voltage and output to the charger 11. Then, as described above, the converter 133 sends the primary feedback value vs(1) according to the output current to the controller 100.

Next, in step 3, the control section 100 controls the high voltage power supply section 1.
The primary feedback value VS (1) from 30 is stored in non-volatile RAM 1.
02 (simply referred to as RAM in FIG. 3).

Next, in step 4, the primary feedback values V 5 (1) and 1
The next command value vo(1) is compared.

If the primary feedback value VS(1) is equal to the primary command value V0(1), it indicates that the output current of the high voltage power supply section 130 has reached the desired value, and in step 5, the primary command value is VS(1) is divided by the standard setting value V (N), and the quotient l is stored in the nonvolatile RAM 102 as a correction coefficient RV.

If the primary feedback value V 5 (1) is not equal to the primary command value V 0 (1) in step 4, the process moves to step 6 and the primary feedback value V 5 (1) is not equal to the primary command value V 5 (1). Value■0
(1) If the additional voltage Δ (for example, 0.IV
) is added to the primary command value V 0 (1), and when it is large, the additional voltage Δ is subtracted, for example, 2. IV or 1.9V is output to the high voltage power supply section 130 as the secondary command value V 0 (2). As a result, the primary feedback value V 5 is higher than that of the high voltage power supply section 130.
The secondary feedback value V 5 (2) different from (1) is the controller 10
0, the control unit 100 clears the non-volatile RAM 102 and sets the secondary feedback value v5 in step 7.
(2) is stored.

Next, in step 8, the secondary feedback values V 5 (2) and 1
Compare with the next command value V 0 (1).

If the two are equal, the process moves to step 9; if the two are not equal, the process moves to step 12.

In step 9, the non-volatile RAM 102 is cleared and the value obtained by dividing the secondary command value vO(2) (=VO(1)±Δ) by the standard setting value V(N) is stored as the correction coefficient RV. . (1.05 or 0.95 in the above example) Next, in step 10, the absolute value of the correction coefficient RV minus 1 and the absolute value of the specified value S (in the above example 0 .05). The absolute value of the correction coefficient RV minus 1 (0.1 in the above example)
) is less than the specified value Sv, the high voltage automatic adjustment ends.

However, the absolute value obtained by subtracting 1 from the correction coefficient RV is the specified value S.
When the voltage exceeds V, in step 11 the operation display section 1
A code indicating an abnormality is displayed at 04 and the process ends.

If in step 8 the secondary feedback value V 5 (2) is not equal to the primary command value v o (1), in step 12 the secondary feedback value V 5 (2) is not equal to the primary command value V 0 (
Depending on whether it is smaller or larger than 1), the value obtained by adding or subtracting twice the additional voltage Δ to the primary command value VO (1) is set as the tertiary command value VO (
3) is output to the high voltage section 130. (2.2V or 1.8V in the above example) As a result, the high voltage power supply unit 130 outputs a secondary feedback value V 5 (2) and a tertiary feedback value V
5(3) is fed back, and in step 13, the non-volatile RAM 102 is cleared and the high voltage power supply section 130 is cleared.
Store the next feedback value v5(3).

Next, in step 14, the tertiary feedback value V 5 (3) and the primary command value V 0 (1) are compared.

When the two are equal, in step 15, the non-volatile RAM 102 is cleared and the tertiary command value V 0 (3
) divided by the primary command value V 0 (1) is the correction coefficient RV
Store as . (1.1 or 0.9 in the above example) Next, in step 16, the absolute value of the correction coefficient RV minus 1 (0.1 in the above example) and the specified value S absolute value (0.1 in the above example)
). If the absolute value of the correction coefficient RV minus 1 is equal to or less than the specified value sv, the high voltage automatic adjustment ends.

However, when the absolute value of the value obtained by subtracting 1 from the correction coefficient RV exceeds the specified value Sv, the process moves to step 17, an abnormality code is displayed on the operation display section 104, and the process ends.

In step 14, if the tertiary feedback value v 5 (3) is not equal to the primary command value V 0 (1), the high voltage power supply unit 1
The feedback value V 5 (N) from 30 is the primary command value V 0 (1
) is repeated until they are equal, and when they are equal, the feedback value V5(N) is set as the primary command value
The value divided by the standard setting value V (N), which is equal to 0 (1), is stored after clearing the non-volatile RAM 102 as a correction coefficient RV, and the absolute value of the number obtained by subtracting 1 from the correction coefficient RV is less than or equal to the specified value SV. If so, the high pressure automatic adjustment ends.

However, the absolute value obtained by subtracting 1 from the correction coefficient RV is the specified value S.
When the value exceeds v, an abnormal hood is displayed on the operation display section 104 and the process ends.

In the copying operation of the device in which the high voltage output automatic adjustment has been completed as described above, the control unit 100 performs Ro M 10
Call the standard setting value V(N) specified from 1,
This is multiplied by the correction coefficient RV called out from the non-volatile RAM 102, and the command value V0(N) is set as the command value V0(N).
30, the output current from the high voltage power supply section 130 is maintained at a standard and appropriate value.

According to the above method, the standard setting value V ( N) is also specified, the non-volatile RAM 102
Since the device-specific error is corrected by the correction coefficient RV called by The current will be at an appropriate value.

Additionally, if the absolute value of the difference between the correction coefficient RV and 1 exceeds the specified value S■, an abnormality code will be displayed on the operation display section 104, so checking the equipment will prevent accidents from occurring. It can be prevented.

〔Effect of the invention〕

As explained above, according to the high-voltage output control device for an electrostatic recording device of the present invention, the output current of the charging means, which fluctuates due to variations in the assembly of the electrostatic recording device, etc., can be automatically corrected to the optimum state. This makes it possible to apply the optimum applied voltage and obtain a copy image of excellent quality.In addition, if the increase/decrease in the set value changed for the correction becomes larger than the specified value, an abnormality will be displayed on the operation display. Since the code is displayed, it is possible to provide an excellent high-voltage output control device for an electrostatic recording device that can prevent accidents from occurring.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the components near the photoreceptor drum of an example of an electrostatic recording device equipped with the device of the present invention and their connections with electric circuits, and FIG. 2 is a block diagram showing the high-voltage output control device of the present invention. FIG. 3 is a flowchart showing high voltage output control of the apparatus of the present invention. lO...Photosensitive drum 11...Charger 13...
- Transfer device 14...Separator 30...Developer 100...Control section 102...Nonvolatile RAM 103...Operation section 130...High voltage power supply section 132...Current detection section

Claims (1)

[Scope of Claims] A high-voltage power supply whose high-voltage output value is controlled by a command value from a control unit, means for feeding back the applied high-voltage output value to the control unit, a ROM storing standard setting values, and an actual adjustment unit. A high-voltage output control device for an electrostatic recording device that is equipped with a non-volatile RAM for storing values and has an automatic adjustment function, and if the actual adjusted value after automatic adjustment differs from the standard setting value by more than the specified value, 1. A high-voltage output control device for an electrostatic recording device, characterized in that it is configured to output an abnormality code to an operation display section.