JP2000264496A - Power controller of image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control the dehumidification corresponding to a moisture condition of the paper by applying a high voltage to the paper for controlling the power of a heat generating means on the basis of an output value by a power controller, and taking the information on paper thickness for compensating for the difference in the moisture condition to the paper thickness to correct the power control condition. SOLUTION: Whether or not a read value on high tension output voltage from a high tension output voltage detecting means 7 is within a prescribed range 1 (when the paper is not moisturized) or a specific range 2 (in a condition that the paper is noisturized), is checked. When it is within the specific range 1, a control means 1 decides that the paper is not moisturized, a switching means 4 is turned off, and the power is not supplied to a heat generating means 3. When it is within the specific range 2, the control means 1 decides that the paper is moisturized, the switching means 4 is turned on, and the power is supplied to the heat generating means 3. When a value of a paper thickness detecting means 8 lies outside of the prescribed range 1 and the specific range 2, that is taken in normal paper passing state, it is decided as being a value which cannot be, and the error processing information is output.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power control device for a heating means for dehumidifying copy paper provided in an image forming apparatus.

[0002]

2. Description of the Related Art In a conventional image forming apparatus, power control for a heat generating means provided for dehumidifying a sheet is performed so that power is applied to the heat generating means when a power switch of an apparatus main body is turned off. Control is performed such that power is applied to the heat generating means when a power plug for supplying power to the apparatus main body is connected to a power supply such as an outlet.

[0003]

In the image forming apparatus which performs the above control, in the former control, when the environment of the image forming apparatus placed in the energized state is in a high temperature and high humidity state, the sheet may absorb moisture. However, since the latter control is always energized, there is a problem from the viewpoint of energy saving.

[0004]

In order to solve the above-mentioned problems, a power control apparatus according to the present invention applies a high voltage to a sheet supplied from a sheet feeding means by a high voltage generating means. At the same time as controlling the power of the heating means in the paper feeding means in accordance with the output value obtained by the above, furthermore, taking in the paper thickness information to correct the difference of the moisture absorption condition with respect to the paper thickness, This is to solve the problem by acting to correct the control condition.

In order to solve the above-mentioned problems, a power control apparatus according to the present invention includes a sheet feeding means, a heating means provided in the sheet feeding means, a power control means for controlling the power of the heating means, High voltage generating means for generating an output voltage, constant current control means for controlling the high voltage generating means with a constant current,
An image forming operation comprising: a high voltage output voltage detecting means for detecting a high voltage output voltage of the high voltage generating means; and a sheet thickness detecting means for detecting a thickness of a sheet fed from the sheet feeding means. Therefore, a high voltage controlled by the constant current control means is applied to the paper fed from the paper feeding means, and the output of the high voltage generation means is detected by the high voltage output voltage detection means, and the high voltage is detected. When the value of the output voltage detecting means is within the predetermined range 1, the power of the heating means provided in the sheet feeding means is controlled, and the value of the high voltage output voltage detecting means is
When the predetermined range 2 or more, the control of the heating means is stopped by the power control means, and the thresholds of the range 1 and the range 2 are set based on information from the paper thickness detecting means. It is characterized by changing.

In order to solve the above-mentioned problems, a power control device according to the present invention includes a sheet feeding unit, a heating unit provided in the sheet feeding unit, and a power control unit for controlling the power of the heating unit. A high voltage generating means for generating a high voltage output current, a constant voltage control means for controlling the high voltage generating means at a constant voltage, and a high voltage output current detecting means for detecting a high voltage output current of the high voltage generating means. Paper thickness detecting means for detecting the thickness of the paper fed from the paper feeding means, and for the image forming operation, the paper fed from the paper feeding means is provided with a constant voltage control means. A high voltage controlled by a constant voltage is applied, the output of the high voltage generating means is detected by a high voltage output current detecting means, and when the value of the high voltage output current detecting means is within a predetermined range, the sheet feeding is performed. Power control of the heating means provided in the means When the value of the high voltage output voltage detecting means is within the predetermined range 2, the control of the heat generating means is stopped by the power control means and based on information from the paper thickness detecting means. In this case, the threshold values of the range 1 and the range 2 are changed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 is a block diagram showing the configuration of a power control apparatus according to the present invention. Reference numeral 1 denotes control means for controlling the image forming apparatus main body as well as the control of the present invention. In this embodiment, it is constituted by a microcomputer.

[0008] Reference numeral 2 denotes a sheet feeding means including a sheet and a sheet feeding cassette for stacking the sheet. Further, 2-A is provided between a paper feeding unit and a photosensitive drum (not shown) for forming an image.
There is a paper feed roller indicated by.

Reference numeral 3 denotes a heating means provided on the bottom plate of the paper feeding means 2 such as a cassette for dehumidifying the copy paper. In this embodiment, a panel heater is used.

Reference numeral 4 denotes switch means for supplying AC power to the heat generating means 3. In this embodiment, a triac is used.

Reference numeral 5 denotes high-voltage generating means having a high-voltage power supply. The high-voltage output is controlled by the constant-current control means 6 at a constant current. The high-voltage output is supplied to one of the sheet feeding rollers indicated by 2-A. ing. The high-voltage power supply usually includes a DC as an input, a high-voltage transformer for generating a high voltage, a diode and a capacitor for rectifying an output boosted by the transformer, and further drives an oscillator circuit for driving the transformer and a signal for the oscillator circuit. It consists of a driving driver and the like.

Reference numeral 7 denotes a high voltage output voltage detecting means, which can obtain an output proportional to the high voltage output voltage. The output of the high voltage output voltage detecting means 7 is connected to the control means 1.

Reference numeral 8 denotes a paper thickness detecting means, which is the above-described 2-A
When the paper passes through the paper feed roller, the amount of displacement of the roller position is detected based on the paper thickness and converted into an electric signal. The output of the paper thickness detection means 8 is A /
It is connected to the D conversion means 9.

Reference numeral 10 denotes a read only memory (ROM) in which a power control program described later is stored.

At the time of the image forming operation, the control means 1
A high-voltage output signal is output to the high-voltage generating means in order to apply a high voltage to the sheet feeding roller of A.

The high voltage generating means 5 is controlled by the constant current control means 6 to generate a high voltage. Also, the paper is fed from the paper feed cassette by the paper feeding means 2 at the start of the image forming operation. Also, the output of the high-pressure generating means is performed.

The voltage from the high-voltage output voltage detecting means 7 is A / D-converted in the control means 1 during the time from when the paper arrives at the drive roller of the above-mentioned 2-A until the paper passes therethrough, It becomes possible to read the value corresponding to the moisture absorption state of the paper together with the impedance of the driving roller 2-A,
By subtracting the known impedance of the driving roller 2-A from this value, only the value corresponding to the moisture absorption state of the sheet can be obtained.

In this embodiment, control is performed to obtain more accurate information by taking in the thickness information of the paper. The paper thickness detecting means 8 detects the paper thickness when the paper reaches the drive roller 2-A. The paper thickness information when the paper is passing between the time when the paper passes and the time when the paper passes is converted into an electric signal.

This paper thickness information is A / D converted by an A / D conversion means (not shown) in the control means 1 and is taken in. In the present embodiment, control is performed as follows based on a known value including the impedance of the driving roller 2-A and information from the paper thickness detecting means.

The read value of the high-voltage output voltage from the high-voltage output voltage detecting means 7 is a predetermined range 1 (a state in which the paper does not absorb moisture) or a predetermined range 2 (a state in which the paper absorbs moisture). The control unit 1 determines that the sheet is not absorbing moisture and turns off the switch unit 4 to perform control, and does not supply power to the heat generating unit 3. When the predetermined range 2 is set, the control unit 1 determines that the sheet is absorbing moisture, controls the switch unit 4 to be turned on, and controls the heating unit 3 to supply power. Perform control.

Further, when the value of the paper thickness detecting means 8 does not fall within the predetermined range 1 and the predetermined range 2, that is, it is determined that the value cannot be obtained in a normal paper passing state, and error processing information is output. .

FIG. 2 shows a flowchart of the above control.

SEQ1 is an interrupt sequence and enters this sequence at regular intervals. In STEP 1, a high-voltage output composed of the high-voltage output generating means 5 and the constant current control means 6 is applied to the drive roller 2-A while the paper is fed from the paper feeding means 2.

In STEP 2, the voltage generated during this time is A / D converted from the voltage value of the high voltage output voltage detecting means 7 and the value is read.

In STEP 3, A / D conversion is performed inside the control means 1 from the output voltage value of the paper thickness detecting means 8 and the value is read.

In STEP 4, it is checked whether the value of the paper thickness detecting means exceeds a predetermined value or not, and in STEP 5, the value of the paper thickness detecting means exceeds a predetermined value. In the case (in the case of thick paper), the set values of the range 1 and the range 2 of the high-voltage output voltage are set as A1 and B1.

In STEP 6, when the value of the above-mentioned paper thickness detecting means does not exceed a predetermined value (in the case of normal paper thickness and thin paper), each set value of the high voltage output voltage range 1 and range 2 is changed to A2 and B2. Set as

At STEP 7, it is determined whether the value of the high-voltage output voltage detecting means is within a plurality of predetermined ranges, and at STEPs 8 to 10, various ranges 1, 2, 1 and other than range 2 are determined. Condition processing is performed under each of the above conditions.

In STEP 8, the predetermined range 1 is set. In this case, it is determined that the sheet is not absorbing moisture, and the switch unit 4 is turned off to stop the power supply to the heating unit of the sheet cassette.

In STEP 9, the predetermined range 2 is set. In this case, it is determined that the sheet has absorbed moisture, and the switch means 4 is turned on to supply power to the heat generating means of the sheet cassette.

In STEP 10, when the value does not fall within the predetermined range 1 and the predetermined range 2, that is, it is determined that the value cannot be obtained in a normal sheet passing state, and error processing information is output.

After performing the above control, the process exits from this control and continues with other controls.

Therefore, as described above, the control means 1 controls the heat generating means provided in the sheet feeding means according to the sheet moisture absorbing condition, thereby controlling the dehumidification of the sheet.

(Second Embodiment) In the first embodiment, the high voltage generating means having the constant current control means is used. However, this can be constituted by the constant voltage generating means.

FIG. 3 is a block diagram of a second embodiment according to the present invention.

The basic configuration is the same as that of FIG.

Reference numeral 5 denotes high voltage generating means. The high voltage output is controlled by the constant voltage control means 6 at a constant voltage, and the high voltage output is supplied to one of the sheet feeding rollers indicated by 2-A.

Reference numeral 7 'denotes a high-voltage output current detecting means which can obtain an output proportional to the high-voltage output current. The output of the high-voltage output current detecting means 7 is connected to the control means 1.

During the time from when the paper arrives at the drive roller of 2-A to when the paper passes, the high-voltage output current detecting means 7 '
A / D conversion of the voltage from the control unit 1 inside the control unit 1 makes it possible to read a value corresponding to the moisture absorption state of the sheet together with the impedance of the driving roller 2-A. By subtracting the impedance of -A, only the value corresponding to the moisture absorption state of the paper can be obtained.

FIG. 4 shows a flowchart of this embodiment.

SEQ1 is an interrupt sequence and enters this sequence at regular intervals. In STEP 1, a high-voltage output composed of the high-voltage output generating means 5 and the constant voltage control means 6 is applied to the drive roller 2-A while the paper is fed from the paper feeding means 2.

In STEP 2, the voltage generated during this period is A / D converted from the voltage value of the high voltage output current detecting means 7 and the value is read.

In STEP 3, A / D conversion is performed in the control means 1 from the output voltage value of the paper thickness detecting means 8 and the value is read.

In STEP 4, it is checked whether the value of the paper thickness detecting means exceeds a predetermined value or not. In STEP 5, the value of the paper thickness detecting means exceeds a predetermined value. In the case (in the case of thick paper), the set values of the range 1 and the range 2 of the high-voltage output current are set as A1 and B1.

In STEP 6, when the value of the above-mentioned paper thickness detecting means does not exceed a predetermined value (in the case of normal paper thickness and thin paper), each set value of the high voltage output current range 1 and range 2 is set to A2.
And B2.

In STEP 7, it is determined whether the value of the high-voltage output current detecting means is within a plurality of predetermined ranges, and in STEPs 8 to 10, various ranges 1, 2, and 3.
Condition processing is performed under each condition other than the range 1 and the range 2.

In STEP 8, the predetermined range 1 is set. In this case, it is determined that the sheet is not absorbing moisture, and the switch unit 4 is turned off to stop the power supply to the heating unit of the sheet cassette.

In STEP 9, the predetermined range 2 is set. In this case, it is determined that the sheet has absorbed moisture, and the switch unit 4 is turned on to supply power to the heating unit of the sheet cassette.

In STEP 10, when the values do not fall within the predetermined range 1 and the predetermined range 2, that is, it is determined that the value cannot be obtained in a normal sheet passing state, and error processing information is output.

After performing the above control, the process exits from this control and continues with other controls.

Therefore, as described above, the control means 1 controls the heat generating means provided in the paper feeding means according to the paper moisture absorbing condition, thereby enabling the control of the dehumidification of the paper.

[0052]

As described above in detail, by executing the dehumidification control in accordance with the moisture absorption state of the paper, the image formation conditions can be stabilized and the dehumidification effect can be obtained with minimum power.

[Brief description of the drawings]

FIG. 1 is a block configuration diagram of a power control device according to a first embodiment of the present invention.

FIG. 2 is a flowchart of a first embodiment of the present invention.

FIG. 3 is a block diagram of a second embodiment of the present invention.

FIG. 4 is a flowchart of a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Control means 2 Paper supply means 3 Heat generation means 4 Switching means 5 High voltage generation means 6 Constant current control means 7 High voltage output voltage detection means 8 Paper thickness detection means 9 AD conversion means

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3F048 AA01 AB01 BA06 BB05 BC00 CA02 EA01 3F343 FA02 FB01 JD34 KB20 MA27 MB19

Claims (2)

[Claims] 1. A sheet feeding unit, a heating unit provided in the sheet feeding unit, a power control unit for controlling power of the heating unit, a high voltage generating unit for generating a high voltage output voltage, and the high voltage generating unit. A constant current control unit for controlling a constant current; a high voltage output voltage detecting unit for detecting a high voltage output voltage of the high voltage generating unit; and a high voltage output voltage detecting unit for detecting a thickness of a sheet fed from the sheet feeding unit. Having a sheet thickness detecting means, for image forming operation, applying a high voltage controlled by the constant current control means to the paper fed from the paper feeding means,
The output of the high voltage generating means is detected by a high voltage output voltage detecting means, and when the value of the high voltage output voltage detecting means is within a predetermined range 1, the power control of the heat generating means provided in the sheet feeding means is performed. When the value of the high-voltage output voltage detecting means is equal to or more than the predetermined range 2, the control of the heat generating means is stopped by the power control means and based on information from the paper thickness detecting means. A power control device for the image forming apparatus, wherein the threshold values of the range 1 and the range 2 are changed. 2. A paper supply means, a heating means provided in the paper supply means, a power control means for controlling power of the heat generation means, a high voltage generation means for generating a high voltage output current, and the high voltage generation means Constant voltage control means for performing constant voltage control on
An image forming operation comprising: a high voltage output current detecting means for detecting a high voltage output current of the high voltage generating means; and a sheet thickness detecting means for detecting a thickness of a sheet fed from the sheet feeding means. For this, the high voltage controlled by the constant voltage control means is applied to the paper fed from the paper supply means, and the output of the high voltage generation means is detected by the high voltage output current detection means, When the value of the high voltage output current detecting means is within a predetermined range, the power of the heat generating means provided in the sheet feeding means is controlled, and the value of the high voltage output voltage detecting means is
In the case of the predetermined range 2, the control of the heating means is stopped by the power control means, and the threshold values of the range 1 and the range 2 are changed based on information from the paper thickness detecting means. A power control device for an image forming apparatus.