JP2010217468A - Fixing device, image forming apparatus and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress sudden voltage changes, at supplying of power from a power source to a heater. <P>SOLUTION: In a fixing device fixes a toner image, transferred to a surface of recording paper, to the surface of the recording paper by applying heat thereto with the heater, the fixing device includes the power source 21 for supplying power to the heater 41, and a power storage device 22 for charging the power of the power source 21. A control section 20 starts supplying power from the power source 21 to the heater 41, and phase control is exerted, such that the angle at which a current is made to flow by each half wave of the current from the power source 21 is gradually increased, the current corresponding to the phase angle of each half wave, at which the current is not caused to flow, is charged into the power storage device 22. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a fixing device for fixing a toner image onto a recording sheet, an image forming apparatus including a facsimile device, a printer, a copying machine, and a multifunction device including the fixing device, and a program.

The image forming apparatus includes a fixing device for heating the printing paper in order to fix the toner on the printing paper, and the heater for heating the fixing device (for example, a resistance heater or a halogen heater) is suddenly fully lit. Then, a large inrush current flows through the heater and voltage fluctuation occurs at the end of the power cord. This voltage fluctuation causes flickering in the lighting in the room where the image forming apparatus is installed (this is called “flicker”). In some cases, the indoor worker may be uncomfortable.
Therefore, for example, in Europe, a regulation is provided so as to suppress voltage fluctuation in the image forming apparatus to a certain level or less.
Therefore, in order to avoid the voltage fluctuation that causes flicker as described above, the heater of the fixing device is not suddenly fully turned on, but is supplied with the heater little by little by phase control (such control). An image forming apparatus to which the method is called “soft start” is provided.

However, the soft start as described above generates a harmonic component in the power supply current due to phase control, so that the power capacitor of the power company is overheated due to the current containing the harmonic component, or the breaker is turned on. There was a risk of malfunction.
For this reason, in Japan and Europe, regulation is also made to suppress the current containing harmonic components in an apparatus including an image forming apparatus to a certain value or less.
On the other hand, due to recent demands for faster operation of image forming apparatuses and shorter start-up times, it is necessary to increase the power consumption of the heater of the fixing device. Fluctuation increases and lighting flickering worsens.

Therefore, when increasing the power of the heater, the phase of the phase control is lengthened to suppress flicker symptoms, and the soft start parameters are optimized to suppress the deterioration of harmonics caused by lengthening the phase control time. However, with the countermeasure method of adjusting the phase control parameters as described above, it is more difficult to clear the above regulations. There was a problem of becoming.
Therefore, in Patent Document 1, a heating member fed from a capacitor and a heating member fed from an AC power source are provided in the heater of the same fixing device, and the capacitor is turned on when power feeding to the heater of the fixing device is started (power feeding on). After heating the heater by power supply from the heater, the heater is continuously heated by power supply from the AC power source.
Thereby, in Patent Document 1, since the temperature of the heater has already increased at the start of power feeding from the AC power source, the inrush current from the AC power source can be reduced, and voltage fluctuation and flicker can be suppressed. Further, since it is not necessary to perform phase control, it is possible to suppress the deterioration of the harmonic current.

However, in Patent Document 1, a heating member that generates heat by power supply from an AC power source and a heating member that generates heat by power supply from a capacitor must be provided at positions that mutually affect the temperature. There has been a problem that the degree of freedom of layout becomes low.
The present invention has been made in view of the above points, and an object of the present invention is to increase the degree of freedom of layout in the apparatus while suppressing the generation of current containing harmonic components.

In order to achieve the above object, the present invention provides a fixing device for fixing a toner image transferred onto a recording paper onto the recording paper by heating with a heater, and a power source for supplying power to the heater and a power storage for charging the power of the power source. When each of the half-waves has a device, the power supply from the power source to the heater is started, and phase control is performed to gradually increase the angle of current flow for each half-wave of the current from the power source. There is provided a fixing device provided with means for charging the power storage device with a current at a phase angle portion where no current flows.
Further, it is preferable to provide means for charging the power storage device in the middle of the phase control.
Further, an energization current detection unit for detecting each energization current value to the heater and the power storage device, and a total value of the energization current values of the heater and the power storage device detected by the energization current detection unit exceeds a predetermined value. It is preferable to provide means for changing the amount of current flowing to the power storage device so that there is no such problem.

In addition, when the power supply from the power source to the heater is stopped by phase control that gradually decreases the angle at which the current flows for each half wave of the current from the power source, the phase angle at which no current flows in each half wave Means may be provided for charging the power storage device with the current of the portion.
Furthermore, it is preferable to provide means for stopping the charging of the power storage device when the power supply from the power source to the heater is stopped by phase control.
Further, it is preferable to provide means for preventing charging of the power storage device simultaneously with the start of the phase control.
Further, the image forming apparatus including the fixing device as described above and a computer start power supply from a power source that supplies power to a heater that fixes the toner image transferred onto the recording paper on the recording paper by heating, When phase control is performed to gradually increase the current flow angle for each half wave of the current from the power supply, the procedure for charging the power storage device with the current at the phase angle portion where no current flows in each half wave is executed. A program is also provided.

The fixing device and the image forming apparatus according to the present invention can suppress rapid voltage fluctuations when power is supplied from the power source to the heater.
In addition, the program according to the present invention can cause a computer to realize a function for suppressing a rapid voltage fluctuation during power supply from the power source to the heater.

FIG. 3 is a block diagram illustrating an internal configuration of the fixing device according to the first exemplary embodiment of the image forming apparatus illustrated in FIG. 2 and a configuration related to power supply control to the fixing device. 1 is a block diagram illustrating a functional configuration of an image forming apparatus common to Embodiments 1 to 4 of the present invention. It is a figure which shows an example of the input waveform of the power supply voltage value to a zero cross detection circuit, and the output waveform of a zero cross detection signal. It is a figure which shows the output waveform of each part when supplying electric power to the fixing heater shown in FIG.

It is a figure which shows the output waveform of each part at the time of turning off electric power feeding to the fixing heater shown in FIG. FIG. 5 is a block diagram illustrating an internal configuration of a fixing device according to a third embodiment of the image forming apparatus illustrated in FIG. 2 and a configuration of each unit related to power supply control to the fixing device. It is a figure which shows the other example of the input waveform of the power supply voltage value to a zero cross detection circuit, and the output waveform of a zero cross detection signal. It is a figure which shows an example of each waveform of a power supply voltage value, a zero cross detection signal, and a charge permission trigger signal.

FIG. 6 is a block diagram illustrating an internal configuration of a fixing device according to a fourth embodiment of the image forming apparatus illustrated in FIG. 2 and a configuration of each unit related to power supply control to the fixing device. It is a wave form diagram of the electric current value with which it uses for description of the detection process of the starting point which starts charge. It is a wave form diagram of the electric current value with which it uses for description of the abnormality detection process when starting charge.

Hereinafter, embodiments for carrying out the present invention will be specifically described with reference to the drawings.
FIG. 2 is a block diagram showing a functional configuration of the image forming apparatus common to the first to fourth embodiments of the present invention.
In this figure, illustration of each function including a power source and a power storage device which will be described later is omitted.
The image forming apparatus 1 is, for example, a multifunction machine having a facsimile function, a scanner function, a copy function, and a print function. The image forming apparatus 1 is a photoconductor 2 that is an image carrier, and optically moves on the photoconductor 2 according to an image signal. And a process unit for performing an image forming process (image forming process) including a charging charger 4, a developing device 5, a transfer charger 6, and a cleaning device 7 and a transfer process.

Further, an upper paper feed cassette 8a and a lower paper feed cassette 8b for supplying paper, a fixing device 10 for thermally fixing the toner image developed by the developing device 5 and transferred onto the paper, and fixing processing by the fixing device 10 are performed. An upper paper discharge tray 9a and a lower paper discharge tray 9b for receiving paper discharged through the paper discharge path P, and a mass feeding device 11 provided as an option are provided.
The upper sheet feeding cassette 8a, the lower sheet feeding cassette 8b, and the large amount sheet feeding device 11 are respectively provided with an upper sheet feeding roller 12, a lower sheet feeding roller 13, and a large amount sheet feeding roller 14 for sequentially feeding sheets. In addition, a registration roller pair 15 is provided in front of the photosensitive member 2 in the process unit to align the paper and the toner image on the photosensitive member 2 in the paper feeding direction (vertical registration adjustment).

The image forming apparatus 1 executes various control processes including image reading, image printing, and fixing device control under the control of a control unit 20 of a microcomputer including a CPU, a ROM, and a RAM. A program is stored in the ROM, and various functions of the laser printer 1 are realized by the CPU executing each procedure of the program using the RAM as a work area.
Under the control of the control unit 20, data such as a character code sent from a host computer including a personal computer is converted into page-unit image data (image information) by an internal controller (not shown), and one line is obtained. Each time an image signal is output to the control unit 20 in the engine driver, the image is printed on the paper.

  That is, the photosensitive member 2 in the process unit is rotated in the direction of the arrow by a main motor (not shown), and the surface is first uniformly charged by the discharge from the charging charger 4, and then the optical scanning device 3 is used for writing. A laser beam modulated in accordance with the image signal is irradiated to form an electrostatic latent image (electrostatic image) corresponding to the written image, and toner is attached to the electrostatic latent image by the developing device 5 to form a toner image. An image forming process is performed.

On the other hand, the sheet is fed by driving any one of the upper sheet feeding cassette 8a, the lower sheet feeding cassette 8b, and the sheet feeding rollers 12 to 14 of the mass feeding apparatus 11 corresponding to the selected sheet. When the leading edge of the sheet is detected by the registration sensor 16, the leading edge of the sheet is pressed against the registration roller pair 15 based on the detection result to correct the skew of the sheet, and the feeding roller 12, 13, or 14 that is being driven temporarily Stop and wait for paper.
Then, the paper feeding roller 12, 13, or 14 that is temporarily stopped at a predetermined timing is driven and the registration roller pair 15 is driven to feed the paper to the transfer unit of the process unit. The toner image is brought into contact with the photoconductor 2 and superimposed on the toner image, and a predetermined voltage is applied to the transfer charger 6 at a predetermined timing to attract the toner to the paper side, and the toner image on the photoconductor 2 is transferred onto the paper.
The conveyance path sensor 17 is a sensor that detects the presence or absence of a sheet on a conveyance path that feeds the sheet to the transfer unit of the process unit.

The paper separated from the photosensitive member 2 is sent from the process unit to the fixing device 10, and the fixing device 10 applies a process of heating and pressurizing the paper and the toner image to melt and fix the toner image on the paper. The processed paper is discharged via the paper discharge path P to the upper paper discharge tray 9a or the lower paper discharge tray 9b.
Further, after the transfer process is completed, the residual toner is removed by the cleaning device 7, and the residual charge is erased by irradiation of a static elimination lamp (not shown) to prepare for the next image forming process.

[Example 1]
FIG. 1 is a block diagram illustrating an internal configuration of the fixing device according to the first exemplary embodiment of the image forming apparatus illustrated in FIG. 2 and a configuration related to power supply control to the fixing device.
The fixing device 10 is supplied with electric power from a power source 21. The power source 21 is, for example, a commercial power source 100V / 50Hz, 100V / 60Hz, or a commercial AC 200V / 50Hz, 200V / 60Hz. It is a power supply.
In addition, for example, 120V / 60Hz, 208V / 60Hz, 240V / 60Hz AC power supply in North America can be used.

  As described above, the control unit 20 is a microcomputer including a CPU, a ROM, and a RAM. The control unit 20 is started up when a main power supply (not shown) of the image forming apparatus 1 is turned on by the user, and power supply control of the fixing device 10 is performed. On / off switching of the fixing heater control unit 30 is controlled by turning on / off the heater trigger signal based on the zero-cross detection signal. In addition, the charging control unit 24 of the power storage device 22 is instructed to be charged by the charging permission trigger signal and the charging amount instruction signal.

  The power storage device 22 includes therein a power storage unit 23 including a lithium ion capacitor, an electric double layer capacitor, a secondary battery, and a USP, and a charge control unit 24, and the charge control unit 24 is charged from the control unit 20. When the permission trigger signal is turned on, the charging process to the power storage unit 23 is started. Further, the charge amount is a value based on a charge amount instruction signal from a separate control unit 20. For example, the charge control unit 24 has a power control element such as an FET or IGBT, and performs high frequency switching of the FET or IGBT when a charge permission trigger signal is turned on. The duty ON width of the high frequency switching is based on the magnitude of the charge amount instruction signal.

The fixing device 10 includes a fixing heater control unit 30, a zero cross detection circuit 34, and a fixing heater 40.
The fixing heater 40 is a heater that heats to fix the toner image transferred to the recording paper. Inside the fixing heater 40, a heater 41 that generates heat by the power via the main triac 31 of the fixing heater control unit 30. Is built-in. The heater 41 is, for example, a heater including a halogen heater and a resistance heater. In the case of the halogen heater, the heater 41 is a heater having a relatively large capacity of 200 W to 1000 W.

The fixing heater control unit 30 includes a main triac 31 that controls power supply to the heater 41, a phototriac 32 that functions as a trigger element for starting and stopping power supply to the main triac 31, and a transistor 33.
The zero cross detection circuit 34 detects the zero cross point of the voltage of the power source 21 and outputs a zero cross detection signal based on the detection result to the control unit 20.
As shown in FIG. 3, a zero-cross detection signal having a predetermined width around the true zero-cross point (the phase of the sine wave is 0 ° or 180 °) of the input of the power supply voltage is output to the control unit 20.
Normally, when the phase control of the fixing heater 40 is performed, the control unit 20 turns the heater trigger signal on or off based on the zero cross detection signal.
The phototriac 32 is a non-zero cross switching type, and thereby, it is possible to control the energization on of the heater 41 at an arbitrary phase angle of the power source 21. The arbitrary phase angle is determined by an instruction of a heater trigger signal from the control unit 20.

When the heater trigger signal input via the transistor 33 is turned on, the phototriac 32 is turned on. When a voltage higher than a specified voltage is applied to the gate terminal of the main triac 31, the main triac 31 is turned on and the power source 21 Is supplied to the fixing heater 40 via the fixing heater control unit 30.
On the other hand, when the heater trigger signal input through the transistor 33 is turned off, the photo triac 32 is turned off, and when the gate terminal of the main triac 31 becomes a specified voltage or less, the power supply to the fixing heater 40 is cut off. The
Due to this characteristic, the timing at which the main triac 31 is turned off is around the zero cross point of the absolute value of the voltage of the power source 21. There are two types of photo triacs 32, one that turns on at zero cross and the other that turns on other than zero cross, but there is no problem in using either type of photo triac.

In the first embodiment, when the phase control of the heater 41 is performed, the current of the power source 21 in the phase angle portion where the current is not supplied to the heater 41 is supplied to the power storage device 22, which is another load, to the heater 41. The power supply harmonic current caused by the current has been improved.
FIG. 4 is a diagram illustrating an output waveform of each part when power supply to the fixing heater is turned on.
As shown in FIG. 4 (e), in the half wave of the power supply current value, the power supply current value (hatched in the figure) of the phase angle portion where the current to the heater 41 (filled part in the figure) does not flow is applied. Is used for charging current to the power storage device.
When detecting the zero cross signal, the control unit 20 turns on the charge permission trigger signal. Thereby, the charging control unit 24 starts the charging process from the AC power source 21 to the power storage unit 23. The charge amount is an amount based on the charge amount instruction signal of the control unit 20.
Thereafter, the control unit turns off the charge permission trigger signal before turning on the heater trigger signal, and turns on the charge permission trigger signal again with the next zero cross signal.
Here, when the energization ON width of the first current to the heater 41 is greater than a certain value, a large current flows through the heater 41 from the first energization.
Therefore, as shown in FIG. 4E, the current-on width of the first current to the heater 41 is made sufficiently small so as not to greatly exceed the rating of the image forming apparatus, and the peak of the current to the heater 41 is reached. Is small, control is performed so that the charging current flows to the power storage device 22 from the first energization of the heater 41 (period indicated by (1) in the figure).

On the other hand, in the first and second energizations to the heater 41 (periods indicated by (1) and (2) in the figure), current flows only to the heater 41, and from the third time the current peak to the heater 41 slightly decreases. You may control to supply a charging current to the electrical storage apparatus 22 by the 7th energization (period shown by 1-7 in the figure).
In the example shown in FIG. 4, the charging current is controlled to gradually increase. However, the charging current may be initially reduced and controlled to gradually increase from the third time to the seventh time.
That is, if the charging current is large from the beginning, flicker may deteriorate. Therefore, as shown in FIG. 4 (f), the charging amount instruction signal is initially indicated with a small charging amount, and the charging amount is gradually increased. By instructing to increase the flicker, flicker can be improved.
Further, the charge amount instruction signal may be an analog signal, but a PWM signal may be used.

When the control shown in FIG. 4 is performed, the energization on width from the first to the seventh energization of the heater 41, the charging current start point (the third energization of the heater 41) and the end point (the heater) (7th energization to the power supply 41), and the on width of the charge and the charge amount in the third to seventh energization of the heater 41 are stored in advance in a storage area (not shown) in the control unit 20. Good.
As for such information, it is preferable to obtain parameters that satisfy both flicker and power supply harmonic current standards by repeating experiments as usual.
In addition, a dead time provided so that charging on and heater energization on are not turned on at the same time is written in advance in the memory of the storage area in the control unit 20, and the control unit 20 turns off the charging permission trigger signal and simultaneously sets a timer. Control is made so that the heater trigger signal is turned on after a lapse of several tens of μs.
In this way, it is possible to avoid the charging permission trigger signal and the heater trigger signal from being turned on simultaneously.

In this way, when phase control is performed to gradually increase the angle at which the current flows for each half wave of the current from the power supply, the current at the phase angle portion where no current flows in the half wave of each current is stored in the power storage device. By charging the battery, it is possible to increase the degree of freedom of layout in the apparatus while suppressing generation of current including power supply harmonics.
In the above-described control process, the case where the heater energization cycle is 7 times during the phase control is shown. However, the number may be increased more than 7 times, or conversely, the present invention can be applied even if the number is reduced. .

[Example 2]
In the second embodiment, when the phase control of the heater 41 is stopped, the current of the power source 21 at the phase angle portion where no current is passed to the heater 41 is caused to flow to the power storage device 22 that is another load. The power harmonic current due to the current to has been improved.
FIG. 5 is a diagram illustrating an output waveform of each unit when power supply to the fixing heater is turned off.
As shown in FIG. 5E, when the phase control of the heater 41 is stopped, in the half wave of the power supply current value, the phase angle portion where the current to the heater 41 (filled portion in the figure) is not flowing. The power supply current value (the hatched portion in the figure) is used as the charging current for the power storage device.
Control is performed so that the charging current flows from the first stop start indicated by 1 in the figure and gradually decreases from the first to the seventh. Further, at the sixth and seventh times when the ON width of energization to the heater 41 becomes a certain value or less, as shown in FIG. 5D, the charging permission trigger signal is turned off to stop the charging current from flowing. .
There are two reasons why the charging current does not flow at the sixth and seventh times.
The first is that the power supply current value for the sixth and seventh times must be sufficiently small to prevent flicker. The second is that it is possible to pass a sufficiently small charging current for the sixth and seventh times. However, the charging current is too small, and there is almost no effect of suppressing power source harmonics caused by the sixth and seventh heater currents.
In the above-described control process, when a sufficiently small charging current is supplied at the sixth and seventh times, there is no problem even if the charging current is supplied at the sixth and seventh times.

Example 3
FIG. 6 is a block diagram showing the internal configuration of the fixing device according to the third embodiment of the image forming apparatus shown in FIG. 2 and the configuration relating to the power supply control to the fixing device. The same parts as in FIG. Reference numerals are assigned and explanations thereof are omitted.
The third embodiment is different from the above in that an AC voltage detection circuit 35 is provided instead of the zero cross detection circuit 34 in the first and second embodiments.
In the zero cross detection circuit, the output of the zero cross detection signal with respect to the power supply voltage as shown in FIG. 7A is obtained, but the zero cross detection is performed for the zero cross point of the true power supply voltage (point indicated by arrow A in the figure). The fall of the signal is accelerated from about 500 μs to about 1 ms.
If an inaccurate zero cross detection circuit is used, the fall may be about 2 ms earlier than the true zero cross point.

Therefore, when charging of the power storage device is started by using the falling edge of the zero-cross detection signal as shown in FIG. 8B as a trigger, the case where a zero-cross detection circuit of about 500 μs to 1 ms or less accurate is used. The charging start point for the power storage device becomes earlier for about 2 ms, and this prevents flicker and harmonics from being accurately suppressed.
Therefore, it is preferable to use an AC voltage detection circuit 35 that can detect a true zero cross point with high accuracy.
As shown in the diagram of FIG. 6, the AC voltage detection circuit performs full-wave rectification (no problem with half-wave rectification) when a sine wave power supply voltage is input, and as shown in the output in the diagram. Output an AC voltage value with a simple waveform.
The control unit 20 samples the output waveform, for example, every 50 μs, and detects the AC voltage value. As for the AC voltage value, a low voltage value is detected when the wave is low, and a high voltage is detected when the wave is high.

The control unit 20 accurately detects the true zero cross point based on this characteristic and sampling every 50 μs, determines the charge start point for the power storage device 22, and outputs a charge permission trigger signal.
For example, when the AC voltage value is detected every 50 μs in a memory not shown in the figure of the control unit 20 and the AC voltage value becomes the lowest numerical value twice consecutively or when a predetermined value or less is detected. A program for determining a true zero cross point may be incorporated and executed.
The reason for the two consecutive times is to prevent erroneous detection of noise as a true zero cross.
In this way, flicker and harmonics can be controlled with higher accuracy than in the first and second embodiments.

Example 4
FIG. 9 is a block diagram illustrating an internal configuration of the fixing device according to the fourth exemplary embodiment of the image forming apparatus illustrated in FIG. 2 and a configuration of each unit related to power supply control to the fixing device. Reference numerals are assigned and explanations thereof are omitted.
In the fourth embodiment, in the configuration of the third embodiment, an energization current detection circuit 25 that performs full-wave rectification of the input of the energization current and outputs a voltage proportional to the input is newly provided. The function of the control unit 20 is slightly different.
When the peak value of the energization current is a predetermined current value or more, the predetermined current or more may be cut off and may not be transmitted to the output side, but there is no particular problem in practice.

The energization current detection circuit 25 monitors the energization current from the power source 21 to the fixing device 10 and notifies the control unit 20 of the energization current value.
The control unit 20 performs the following two functions based on the energization current value notified from the energization current detection circuit 25.
One is to monitor the current to the heater 41 during the phase control when the heater 41 is turned on from the unlit state, and start charging the power storage device 22 when the peak of the current falls below a predetermined value. Detect the starting point.
The other is whether the energization current obtained by adding the current of the heater 41 and the charging current to the power storage device 22 does not exceed a threshold value stored in a storage area (not shown) in the control unit 20 in advance. Determine whether.

Next, a start point detection process for causing the power storage device to start charging will be described.
FIG. 10 is a waveform diagram of current values for explaining the start point detection process for starting charging.
The control unit 20 sets a threshold value of the current peak of the heater 41 that starts charging in advance.
After the start of phase control of energization to the heater 41, for example, the energization current value is sampled every 50 μs, and the energization current value to the heater 41 is less than or equal to the heater current threshold in half-wave cycle units of the power source 21 ( Look for the time point indicated by the broken line in the figure.
Then, from the point indicated by arrow B in the figure, charging of the power storage device 22 is started from the next half-wave cycle in which it is detected that the current value is equal to or less than the threshold value of the heater current in half-wave cycles.
By controlling in this way, it is possible to prevent an excessive current from flowing by adding a charging current to the heater current.

FIG. 11 is a waveform diagram of current values for explaining the abnormality detection process when charging is started.
The control unit 20 detects the energization current value in units of 50 μs for each half wave cycle in which the charging current flows to the power storage device 22, and substitutes the detected energization current value into a predetermined calculation formula, thereby The effective current value of is obtained.
By monitoring whether the effective current value does not exceed a predetermined threshold value stored in advance, an abnormality detection process for the sum of the charging current to the power storage device 22 and the current to the heater 41 is performed. Can do.
When the effective current value exceeds a predetermined threshold value, the control unit 20 stops energization without passing the current to the heater 41 and the charging current to the power storage device 22 in the next half-wave cycle, and an error is detected in the image forming apparatus. It communicates to the system management department and performs abnormality processing.
By monitoring the energization current in this manner, the safety and reliability of the image forming apparatus can be improved.

FIG. 9 shows a configuration in which the energization current detection circuit 25 is placed in front of the heater 41 and the power storage device 22. However, if the current-carrying current detection circuit 25 is placed in front of all loads of the image forming apparatus including the power source 21, the image is displayed. The energization current of the entire forming apparatus can be detected.
By using the AC voltage detection circuit in combination, the power consumption of the image forming apparatus can be calculated in real time.

  The image forming apparatus, the fixing apparatus, and the program according to the present invention can be applied to an image processing apparatus including a facsimile machine, a printer, a copying machine, and a multifunction machine.

1: Image forming device 2: Photoconductor 3: Optical scanning device 4: Charge charger 5: Developing device 6: Transfer charger 7: Cleaning device 8a: Upper paper feed cassette 8b: Lower paper feed cassette 9a: Upper paper discharge tray 9b: Lower discharge tray 10: Fixing device 11: Mass feeding device 12-14: Feed roller 15: Registration roller pair 16: Registration sensor 17: Conveyance path sensor 20: Control unit 21: Power supply 22: Power storage device 23: Power storage unit 24: Charging control unit 25: Energizing current detection circuit 30: Fixing heater control unit 31: Main triac 32: Photo triac 33: Transistor 34: Zero cross detection circuit 35: AC voltage detection circuit 40: Fixing heater 41: Heater P: Paper discharge Road

JP 2004-240386 A

Claims (8)

In a fixing device for fixing a toner image transferred on a recording paper onto the recording paper by heating with a heater,
A power source for supplying power to the heater and a power storage device for charging the power of the power source;
A phase in which no current flows in each half wave when the power supply from the power source to the heater is started and phase control is performed to gradually increase the angle at which the current flows every half wave of the current from the power source. A fixing device comprising means for charging a current of a corner portion to the power storage device.   The fixing device according to claim 1, further comprising means for charging the power storage device in the middle of the phase control. Energization current detection means for detecting each energization current value to the heater and the power storage device;
A means is provided for changing the amount of current supplied to the power storage device so that the total value of the current values of the heater and the power storage device detected by the power supply current detection means does not exceed a predetermined value. The fixing device according to claim 1 or 2.   When the power supply from the power source to the heater is stopped by phase control that gradually reduces the angle at which the current flows for each half wave of the current from the power source, the phase angle portion that does not flow current in each half wave The fixing device according to any one of claims 1 to 3, further comprising means for charging the power storage device with a current.   5. The fixing device according to claim 4, further comprising means for stopping charging of the power storage device halfway when power supply from the power source to the heater is stopped by phase control.   6. The fixing device according to claim 1, further comprising means for preventing charging of the power storage device simultaneously with the start of the phase control.   An image forming apparatus comprising the fixing device according to claim 1.   The computer starts power supply from a power supply that supplies power to a heater that fixes the toner image transferred onto the recording paper on the recording paper by heating, and gradually increases the angle at which the current flows every half wave of the current from the power supply. A program for executing a procedure for charging a power storage device with a current at a phase angle portion in which no current flows in each half wave when phase control for increasing is performed.

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