JPH05260232A - Image forming device with uninterruptive power supply - Google Patents

Abstract

PURPOSE:To allow the image forming device provided with an uninterruptive power supply to effectively utilize power of an uninterruptible power supply so as to facilitate the post-processing on the occurrence of a power failure. CONSTITUTION:The image forming device with interruptible power supply having an interruptive power supply 91 supplying power for a prescribed time when an AC power supply 90 is interrupted is provided with an AC voltage reduction detection means detecting the drop of an AC voltage of an AC power supply 90, a momentary interruption simulation means interrupting momentarily the AC power supply 90 to measure a reset time of the image forming device, and a control means 260 controlling the start of save processing by the interruptive power supply 91 after lapse of a prescribed shorter time than a reset time detected by the momentary interruption simulation means when the drop of the AC voltage is detected by the AC voltage reduction detection means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus with an uninterruptible power supply such as a copying machine.

[0002]

2. Description of the Related Art Generally, in an image forming apparatus, for example, a copying machine, if the AC power is cut off during a copying operation, all the operations are stopped, and a transfer sheet before transfer, during transfer, or after transfer is placed in the copying machine. I will remain. Then, when the power is restored, the copying machine is initialized and the jam is detected because the transfer paper remains on the conveyance path. Therefore, the operator must perform the jam processing and reset the mode such as the number of copies.

Further, if the AC power supply is cut off while the operator is in the standby mode and the mode is being set by the operator, the mode will be reset even if the power is restored, so that the setting must be made again, which is troublesome.

Therefore, by adding an uninterruptible power supply, power is supplied only during a certain period when the power is cut off.
For example, the transfer paper in the copying machine can be ejected outside the machine by driving the transport motor, etc. Also, when the power is cut off, a certain power is sent by generating this power cutoff signal from the uninterruptible power supply. Since it is impossible to operate all the motors, fixing heaters, etc., the copying operation is stopped from that moment and the transfer paper is not fed, so that it is possible to eliminate the troublesome processing after the power is restored. is there. Such an operation is a special save process called a shutdown sequence operation.

[0005]

However, even in the case of having an uninterruptible power supply as described above, considering the power supply situation,
It often causes inconvenience.

[0006] First, in the case where the uninterruptible power supply is provided, when a voltage drop or interruption of the AC power supply is detected, power is supplied from the uninterruptible power supply to perform a special saving process called a shutdown sequence operation. Since the machine can normally operate for a while even after the AC power supply voltage has been reduced or cut off, it is not necessary to perform the shutdown sequence immediately after the AC power supply voltage reduction or cutoff is detected. .. On the contrary, the AC power supply may return to the normal state while the copier is operating normally due to the voltage drop or interruption of the AC power supply. Therefore, even in such a case, the shutdown sequence is performed. As a result, the process becomes useless and the power of the uninterruptible power supply is wasted.

In the copying machine, however, optional equipment such as an ADF (Automatic Document Feeder) and a sorter is installed for use only in the copying machine main body and for higher functionality and higher productivity. Since the normal operation time differs depending on the main body of the copying machine and the optional equipment, it is difficult to uniformly set the time from the voltage drop or interruption of the AC power supply to the start of the shutdown sequence operation.

Further, if power is supplied from the uninterruptible power supply to all the units of the copying apparatus even during standby, as in the copying operation, useless power consumption results.

Second, there is a problem of the capacity of the storage battery used as the uninterruptible power supply. That is, in the shutdown sequence, when the commercial AC power is cut off, the uninterruptible power supply discharges the transfer paper in the middle of copying, so that the jam processing after the power is restored can be eliminated. However, depending on the state of charge of the battery of the uninterruptible power supply, the shutdown sequence may not be executed normally. Possible causes of insufficient battery charge include a case where a power failure occurs again without charging the battery for a sufficient time after the previous power failure, and a case where the battery itself is deteriorated. As a result, the transfer sheet may not be ejected and the jam process may be required after the power failure is restored. In other words, the result is the same as when there is no uninterruptible power supply.

Further, even when the transfer paper is stopped in the paper transport path, there are a position where it is difficult to take out and a position where it is easy to take out later. If it is not possible to take it out,
It is easy to take out when it is in the separation conveyance section before fixing.

[0011] Here, regarding the capacity of the storage battery, there is a problem that deterioration of the battery is difficult to understand when there is no load. Generally, in a storage battery, a plurality of cells are connected in series to increase the voltage. For example, in the case of a lead storage battery, the output voltage of one cell is about 2V and the voltage during charging is 2.3V. Therefore, when a 24V battery is used as the uninterruptible power supply, the charging voltage is 27.6V. That is, when considering the state of charge of the battery with respect to the charging time, the charging voltage and the charging current are almost constant values in the latter half of charging even with a normal battery, but the charging capacity is increased thereafter. Therefore, it is difficult to predict the charge capacity from the instantaneous value of the charge voltage or charge current. On the other hand, when the battery is defective, for example, if one of the 12 cells of 24V is defective and the impedance is high, the charging current does not flow because the impedance is high, and the charging voltage does not flow because the charging current does not flow. High from the beginning. Also in this case, it is difficult to predict the charging state from the charging current and the charging voltage.

The power failure may occur not only during copying but also during standby. On the contrary, the probability of power failure is generally higher when waiting. When a power failure occurs despite being on standby, copying can be done with a copying machine having an uninterruptible power supply by pressing the copy key, and if the battery capacity is sufficient, copying can be completed normally, When the battery capacity is insufficient as described above, the transfer paper may not be normally ejected.

Thirdly, there is a problem that it is insufficient to cope with the overcurrent. That is, the copying speed of the copying machine is increasing year by year, and the capacity of the fixing heater, the light quantity of the lamp, the motor power, etc. is increasing accordingly, and the number of machines exceeding the current limiting capacity 15A of the indoor wiring is increasing. Further, in recent years, the copying machine has been in the trend of digitalization, and the current consumption of the DC power source has been increasing accordingly. This tendency is particularly remarkable in a copying machine having an image memory. here,
Among the copiers that consume the most power, there are fixing heaters, exposure lamps, and DC power supplies. Among these, the fixing heater controls the temperature by controlling the phase of the AC power source or controlling the ON / OFF of the AC power source. Therefore, the input current to the fixing heater flows in a sine wave shape or a pulsating current shape. The exposure lamp is a fluorescent lamp or a halogen lamp.In the case of a fluorescent lamp, the AC power supply is once converted into DC, and this DC output is oscillated at a high frequency for high-frequency lighting. In the case of a halogen lamp, phase control is performed. There are cases where it is lit by and cases where it is lit by direct current. In the case of a DC power supply, after rectifying AC, smooth it with a capacitor to make a primary voltage, oscillate this at high frequency, and rectify the secondary voltage by transformer coupling to obtain a stabilized DC voltage. ing. Since the DC power supply is rectified and then smoothed by a capacitor, it is called "capacitor input", and the input current is 9
It flows like a peak near 0 degree. Therefore, the power factor is poor,
It is about 55% with a general DC power supply. If the power factor is bad,
If the power factor is 55% even if the input current flows more than the power consumption and 15A flows, the power consumption is 825.
Only W. That is, the utilization efficiency of electric power with respect to the consumption current is very poor.

In order to improve the power factor, there are a method using a choke coil and a method using an active filter. The method using a choke coil is simple, but 75%
Power factor only goes up to the top. The method using the active filter can increase the power factor to 95% or more, but the number of parts is large and the cost is high. In any case, it can be said that the input current can be reduced by improving the power factor with the same power consumption.

Fourth, there is a problem of temporary increase in current. This is, for example, an inrush current (surge current). For example, in the process in which the fixing heater rises from the normal temperature state to the high temperature, a current several times as large as that in the rated state flows. When the exposure lamp is a halogen lamp, a large current flows when it is turned on. In addition, a large current also flows through the motors at the time of start-up or return, and if the motor is equipped with an image memory, the write clock becomes faster at the time of writing to the memory, so a large current temporarily flows. Such a large current, together with the poor power factor, results in operating the breaker exceeding 15 A, which is not preferable.

Fifth, there is a problem that the processing time is delayed due to the power limitation. That is, normally, the power consumption of the copying machine is determined by the rated capacity of the AC power source, and the power of each unit in the copying machine is distributed from the rated capacity of the AC power source. The electric power of the heater will also be limited. As a result of such power limitation, it takes a long time for the fixing heater to rise, and the temperature of the fixing roller decreases even if 100% of electricity is supplied to the fixing heater when continuous copying is performed. Therefore, the number of continuous copies must be limited. In other words, it does not limit the number of continuous copies, but instead slows down the copying speed.

After all, it can be said that how to effectively use the power of the uninterruptible power supply in a copying machine or the like equipped with the uninterruptible power supply.

[0018]

According to a first aspect of the present invention, in an image forming apparatus with an uninterruptible power supply having an uninterruptible power supply for supplying a predetermined time when the AC power supply is cut off, the AC voltage of the AC power supply is lowered. AC voltage drop detection means for detecting the, AC power supply is momentarily cut off, instantaneous interruption simulation means for measuring the reset time of the image forming apparatus, and when the AC voltage drop is detected by the AC voltage drop detection means The control means is provided for controlling the start of the evacuation processing by the uninterruptible power supply after a lapse of a predetermined time shorter than the reset time detected by the instantaneous interruption simulation means.

According to a second aspect of the present invention, in an image forming apparatus with an uninterruptible power supply having an uninterruptible power supply for supplying power for a predetermined time when the AC power supply is cut off, an AC voltage drop detecting a drop in the AC voltage of the AC power supply. A detection unit, a drop time point determination unit that determines the occurrence time point of the AC voltage drop, and a power supply from the uninterruptible power supply to all units of the image forming apparatus when the AC voltage drop occurrence point is during image formation. A supply destination switching means for supplying power from the uninterruptible power supply only to the DC power supply unit in the image forming apparatus is provided during standby.

According to a third aspect of the present invention, in an image forming apparatus with an uninterruptible power supply that has an uninterruptible power supply that supplies power for a predetermined time when the AC power supply is cut off, an AC voltage drop detecting a drop in the AC voltage of the AC power supply. A detection unit, a drop time point determination unit that determines a time point when an AC voltage drop has occurred, and an AC voltage drop that causes the image forming apparatus to supply power from the uninterruptible power supply when the AC voltage drop time point is during image formation. And a power supply switching means for turning off the power supply to the image forming apparatus when the occurrence time of the above is in standby.

According to a fourth aspect of the invention, in the third aspect of the invention, the power switch determination means for detecting the open / closed state of the power switch with respect to the AC power source when the power supply switching means turns off the power supply, and the power switch is closed. A mode storage unit is provided for storing the setting mode at that time in the image forming apparatus when the state is determined.

According to a fifth aspect of the invention, power supply means for individually supplying power to a plurality of units inside the image forming apparatus based on an AC power supply, and uninterruptible power supply for supplying a predetermined time when the AC power supply is cut off. In an image forming apparatus with an uninterruptible power supply having a power supply, a current limiting unit that limits an input current from the AC power supply to the uninterruptible power supply, a consumption current detection unit that detects a consumption current flowing to each unit, and detection. And a supply source switching means for switching power supply from the corresponding power supply means to the uninterruptible power supply for the unit whose consumed current exceeds a certain value.

In the invention according to claim 6, in the invention according to claim 5, priority is given to the switching of the power supply source to the unit based on the current consumption in each unit.

According to a seventh aspect of the present invention, in an image forming apparatus with an uninterruptible power supply having an uninterruptible power supply that supplies electric power for a predetermined time when the AC power supply is cut off, a first fixing heater and a second fixing heater are provided in a fixing roller. The first roller is provided from the time of power-on until the fixing roller rises to a predetermined temperature.
Power supply control means is provided for supplying power from the AC power supply to the fixing heater and supplying power from the uninterruptible power supply to the second fixing heater.

According to the present invention, in an image forming apparatus with an uninterruptible power supply having an uninterruptible power supply which supplies electric power for a predetermined time when the AC power supply is cut off, from when the power is turned on until the fixing roller rises to a predetermined temperature. During this period, power supply control means for supplying electric power to the fixing heater in the fixing roller from both the AC power supply and the uninterruptible power supply is provided.

According to a ninth aspect of the present invention, in an image forming apparatus with an uninterruptible power supply that has an uninterruptible power supply that supplies electric power for a predetermined time when the AC power supply is cut off, a first fixing heater and a second fixing heater are provided in a fixing roller. Power is supplied from the AC power source to only the first fixing heater until a predetermined condition is satisfied during image formation, and when the predetermined condition is satisfied, power is supplied from the AC power source to the first fixing heater. And a power supply control means for supplying power to the second fixing heater from the uninterruptible power supply.

According to a tenth aspect of the present invention, in an image forming apparatus with an uninterruptible power supply that has an uninterruptible power supply that supplies electric power for a predetermined time when the AC power supply is cut off, the image forming apparatus with the uninterruptible power supply is provided in the fixing roller until a predetermined condition is satisfied during image formation. Power supply control means is provided for supplying power to the fixing heater from only the AC power supply, and supplying power to the fixing heater from both the AC power supply and the uninterruptible power supply when a predetermined condition is satisfied.

[0028]

According to the first aspect of the present invention, the reset time at the time of the instantaneous interruption is measured by the instantaneous interruption simulation means in advance, and immediately after the AC voltage drop detecting means detects the voltage drop or interruption of the AC power supply. Does not start the evacuation process by the uninterruptible power supply, but does the evacuation process if the power supply is not restored even after the elapse of a predetermined time within the reset time, so even if the AC power supply is immediately restored There is no wasteful processing by the power supply, wasteful power consumption of the uninterruptible power supply can be prevented, and even if it takes time to restore, the evacuation processing is performed within the reset time, so transfer paper jam status The recovery of the uninterruptible power supply system is ensured without recovering as it is, and the reset time at this time is also set automatically by the instantaneous interruption simulation. Become a thing.

According to the second aspect of the present invention, even if the AC power source voltage drop occurs, if it is during image formation, power is supplied to all the units from the uninterruptible power source and the image forming operation at that time is performed. However, in standby mode, power is supplied only from the uninterruptible power supply to the DC power supply unit, so wasteful power consumption of the uninterruptible power supply is prevented and only the minimum necessary processing by the DC power supply unit is secured. it can.

According to the third aspect of the invention, even if the uninterruptible power supply is provided, if the voltage drop of the AC power supply is in standby without fear of transfer paper remaining or the like, power is supplied to the image forming apparatus. Since the power is turned off, it is possible to reliably prevent wasteful power consumption of the uninterruptible power supply.

At this time, according to the invention as set forth in claim 4, when the power supply is turned off, the open / closed state of the power switch is checked. Since it is recognized as the latter one and the setting mode is stored, there is no trouble of resetting the mode after the power is restored.

According to the fifth aspect of the invention, when the detected current consumption exceeds a certain value, the power supply to the unit is switched from the AC power supply to the uninterruptible power supply, so that an input current exceeding the rating flows. In this case, the uninterruptible power supply compensates for the excess, and it is possible to prevent the breaker from operating unnecessarily due to a temporary increase in current. At this time, the input current of the uninterruptible power supply does not flow more than the current set by the current limiting means.

In this case, according to the invention as set forth in claim 6, since the priority is given to the switching of the power supply source according to the current consumption in each unit, the uninterruptible power supply is used for the one with the largest current consumption. By substituting the power supply to the device, it is possible to more reliably compensate the operation within the rating.

According to the invention described in claims 7 and 8,
Even when the AC power supply is normal, the uninterruptible power supply is also used to supply power to the fixing heater, so that the fixing roller can be quickly raised to a predetermined temperature under conditions where power distribution is restricted. The processing speed will not be delayed.

Similarly, according to the ninth and tenth aspects of the present invention, during image formation, even if the AC power supply is normal, the uninterruptible power supply is also used for supplying power to the fixing heater under a predetermined condition. It is possible to prevent the temperature of the fixing roller from decreasing under the condition that the power distribution is restricted, and it is possible to perform the image forming process without being restricted by the processing speed being slowed.

[0036]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS. First, the configuration and operation of a digital copying machine as an image forming apparatus to which the present invention is applied will be described. FIG. 2 is a schematic diagram showing the overall configuration of the digital copying machine. When roughly classified, an automatic document feeder (ADF) 2, a sorter unit 3, a double-sided reversing unit 4, etc. are attached to the copying machine main body 1. To be done.

The copying machine main body 1 comprises a scanner section, an optical writing section, a photoconductor section, a developing section, a paper feeding section and the like. Here, the schematic configuration and operation of each unit will be described. First, the scanner unit is equipped with a light source 5 with a reflecting mirror and a first mirror 6, and a first scanner that moves at a constant speed,
Equipped with 2nd and 3rd mirrors 7 and 8, 1/2 of the 1st scanner
And a second scanner that moves following the first scanner at a speed of. The original on the contact glass 9 is optically scanned by these first and second scanners, and the reflected image is guided to the lens 11 via the color filter 10 and imaged on the one-dimensional solid-state image pickup element 12. Here, a fluorescent lamp or a halogen lamp can be used as the light source 5, but in view of wavelength stability and long life, a fluorescent lamp is generally used.
A CCD is generally used as the one-dimensional solid-state imaging device 12. Since the image signal read by the one-dimensional solid-state imaging device 12 is an analog value, it is A / D converted and various image processings (for example, binarization, multi-value conversion, gradation processing, etc.) are performed by the image processing board 13. Magnification processing, editing processing, etc.) is performed and converted into a digital signal as a set of spots.

In order to obtain color image information, here, a color filter 10 that allows only the information of the required color to pass through is arranged in the middle of the optical path guided from the document to the solid-state image pickup device 12. Therefore, the color filter 10 is switched in accordance with the scanning of the original, and the multi-transfer and double-sided copy functions are performed each time, so that various kinds of copies can be created.

Next, the optical writing section will be described. The image processing after the image processing is performed by the optical writing unit 15 in the form of a set of light points by raster scanning of laser light.
Written on 6. 3 and 4 show the optical writing unit 15
FIG. 3A is a plan view and FIG. The laser light emitted from the semiconductor laser 17 is collimated by the collimator lens 18 and is collimated by the aperture 19 into a uniform luminous flux. After that, it is incident on the polygon mirror 21 in a form compressed in the sub-scanning direction by the first cylinder lens 20. The polygon mirror 21 formed in an accurate polygonal shape is rotated in a certain direction at a constant speed by the polygon motor 22, and the laser light incident on this polygon mirror 21 is
The reflected light is deflected by the rotation of the polygon mirror 21. The deflected laser light enters the fθ lens 23, is converted so that scanning light having a constant angular velocity is scanned on the photoconductor 16 at a constant speed, and is imaged on the photoconductor 16 so as to have a minimum light spot. At this time, the light that has passed through the fθ lens 23 is outside the image area and is detected by the synchronization detecting mirror 24 by the synchronization detecting mirror 24.
Guided by the optical fiber, propagated to the sensor section by the optical fiber, and provided for synchronization detection which serves as a reference for cueing in the main scanning direction. The process of outputting the image data for one line after a lapse of a fixed time after the synchronization signal is output is similarly repeated for each line,
Two-dimensional optical writing is performed.

In the photosensitive member section, the photosensitive member 16 is
It has a photosensitive layer on the peripheral surface which is sensitive to a semiconductor laser beam having a wavelength of 780 nm, and such a photosensitive layer includes an organic photoconductor (OPC), α-Si, Se-Te, etc. Uses OPC). Generally, in the case of laser writing, a negative / positive (N / P) process of shining light on an image portion and a positive / positive (P / P / P / n) process of shining light on the background
P) There are two types of process, but here, the former N
/ P process method. Also, the charger 2
Reference numeral 8 denotes, for example, a scorotron type, which is configured such that the surface of the photoconductor 16 is uniformly negatively charged, and when the image forming portion is irradiated with laser light, the electric charge at that portion is dropped. As a result, the background portion of the surface of the photoreceptor 16 is -750 to -800V,
The image portion has a potential of about −500 V, and an electrostatic latent image is formed on the surface of the photoconductor 16. The developing device 29 applies a bias voltage of -500 to -600 V to the developing roller,
It is visualized by attaching charged toner to the latent image.
The visualized image is transferred by applying a + charge by the transfer charger 30 onto the transfer paper that is fed and conveyed in synchronization with the photoconductor 16. After the transfer, the transfer paper is subjected to AC charge removal by the separation charger 31 and separated from the photoconductor 16. After the transfer, the residual toner is scraped off and removed by the cleaning device 32 on the photoconductor 16, and the residual potential is erased by the light irradiation of the static elimination lamp 33.

Next, the paper feeding section will be described. Here, it is possible to carry out double-sided copying or re-feeding by having a plurality of paper feed cassettes 35 and passing the transfer paper once transferred through the re-feeding loop 36. When one of the plurality of paper feed cassettes 35 is selected and the start button is pressed, the paper feed roller near the selected paper feed cassette 35 rotates and paper is fed until the leading edge of the paper hits the registration roller 37. It At this time, the registration roller 37 is stopped, but rotation is started at the timing of the image position on the photoconductor 16 and the paper is fed to the photoconductor 16. After that, as described above, the transfer / separation operation is performed, and the transfer sheet after the transfer is suctioned and conveyed by the separation / conveyance unit 38. After that, the image is fixed by the heat fixing device 39, and during normal copying, it is guided to the sheet discharge port on the sorter unit 3 side by the switching claw 39. On the other hand, at the time of multiple copy, the paper discharge path to the sorter unit 3 side is closed by switching the switching claw 39, and the paper is guided to the registration roller 37 side again through the lower paper re-feeding loop 36. Further, in the case of double-sided copying, there are two kinds of cases, that is, the copying machine body 1 alone and the case where the double-sided reversing unit 4 is used. The guided paper is further guided downward by the switching claw 40, and further guided by the lower switching claw 41 onto the tray 42 below the re-feeding loop 36. Then, the sheet is fed back from the tray 42 by the roller 43 in the re-feeding loop 36 in an inverted state, fed to the registration roller 37 side and used for double-sided copying.

Next, the ADF 2 will be described. The ADF 2 automatically performs the operation of guiding the originals one by one onto the contact glass 9 and discharging the originals after copying. That is, the originals placed on the original feeding table 51 are separated and fed one by one by the feeding roller 52, and are conveyed and set to a predetermined position on the contact glass 9 by the conveying belt 53. When a predetermined number of copies (exposure) are completed, the original is again discharged onto the discharge tray 54 by the conveyor belt 53.

The sorter unit 3 selectively discharges the transfer paper discharged from the copying machine main body 1 in, for example, page order, page by page, or a preset bin 55.

Further, the double-sided reversing unit 4 will be described. As described above, in the double-sided copying using only the copying machine main body 1, only the double-sided copying can be performed for each sheet. That is, when making a double-sided copy for a plurality of sheets collectively, the double-sided reversing unit 4 is operated by the switching claw 39.
Sent to. The paper that has entered the double-sided reversing unit 4 is discharged and stacked on the double-sided tray 57 by the paper discharge roller 56. At this time, the transfer paper is aligned vertically and horizontally. The transfer sheets stacked on the double-sided tray 57 are re-fed by the re-feeding roller 58 when the back side is copied. At this time, the switching claw 41 directly guides the sheet to the refeeding loop 36.

Next, the electrical equipment control system will be described.
First, FIG. 5 shows a block diagram of the entire electrical equipment control.
The main control board 61 controls the scanner control circuit 62, the sorter control board 63, the double-sided control board 64, the paper feed control board 65, and the operation unit 66 and the application system 67. Has been done.
A power circuit 68 is connected to the main control board 61 and the like from a general commercial AC power source 90 via an uninterruptible power source 91.

The scanner control circuit 62 will now be described. As shown in FIG. 6, the ADF control plate 69 for the ADF 2, the ballast 70 for the fluorescent lamp (light source) 5, the scanner motor 71, the memory unit 72, etc. In addition, an APS solenoid, an ADF solenoid, etc. are connected. For the memory unit 72, the read signal from the CCD (solid-state image sensor) 12 is an image preprocessor (IPP) 73,
It is input via an image process unit (IPU) 74, and is also connected to an external storage device 75.

Further, as shown in FIG. 7, sensors 76 such as an inlet sensor, a bin sensor, a drive motor 77, loads 78 such as an interrupt solenoid are connected to the sorter control plate 63. The double-sided control plate 64 includes solenoids 79 such as a tray solenoid and clutches 8 such as a paper feed clutch.
0, a jogger motor 81, and sensors 82 such as paper discharge detection are connected.

Further, as shown in FIG. 8, the sheet feeding control plate 65 has solenoids 83 such as a toner replenishing solenoid, clutches 84 such as a registration clutch, and various sensors 85.
At the same time, an intake fan 86 and a conveyance fan 87 are connected.

Looking at the power supply circuit 68, FIG.
As shown in FIG. 5, electric power is supplied to the AC system load from the general commercial AC power supply 90, while a DC voltage is generated by the DC power supply 92, and the main control board 61 and the scanner control circuit 62 are generated.
Is being supplied to. Here, because of the AC system load, AC
A drive plate 93, a main motor drive plate 94, a polygon motor drive plate 95, and a high-voltage power supply 96 are prepared. A power supply monitoring unit 97 is connected to the AC power supply 90 and the uninterruptible power supply 91.

On the other hand, such an electric equipment control system will be described from another point of view. As shown in FIGS. 9 and 10, the main control board 61 as a control unit of the digital copying machine used in this embodiment has two CPUs 101 and 102, and the CPU 101 takes charge of sequence-related control. The CPU 102 is configured to take charge of operation-related control. CPUs 101 and 102 are
Connected by serial interface.

First, the sequence control side will be described with reference to FIG. The CPU 101 for sequence control is
It sets and outputs conditions related to paper transport timing, image formation, paper size detection sensor, sensor 103 for paper transport such as paper discharge detection and registration detection, double-sided reversing unit, high-voltage power supply unit, relay, solenoid, motor, etc. The driver 104, the sorter unit 3, the scanner unit 105, etc. are connected.

Regarding the sensor 103, as described above, a paper size sensor that detects the size and orientation of the paper loaded in the paper feed cassette 35 and outputs an electric signal according to the detection result, registration detection, and paper discharge detection. There are inputs from a sensor for detecting the presence or absence of supply such as oil end and toner end, and a sensor for detecting machine abnormality such as door open and fuse blown.

Regarding the double-sided reversing unit, as described above, the motor for aligning the paper width, the paper feed clutch, the solenoid for changing the transport path, the paper presence / absence detection sensor, the home position sensor of the side fence for paper width alignment,
There are sensors related to paper transport. The high-voltage power supply unit applies predetermined high-voltage power to the outputs of the charging charger, the transfer charger, the separation charger, and the developing bias electrode only by the duty obtained by the PWM control. In the PWM control, the feedback value of each high-voltage power output is converted into a digital value by A / D conversion and is controlled to be equal to the target value.

Regarding the driver relationship, as described above,
Paper feed clutch, registration clutch, counter, motor,
There are toner replenishing solenoids, power relays, fixing heaters, and the like.

Further, it is connected to the sorter unit 3 by a serial interface, and a CP for sequence is used.
The paper is conveyed at a predetermined timing according to a signal from U101, and is ejected to each bin 55.

Further, a fixing temperature, a photosensor input, a monitor input of the semiconductor laser 17, a reference voltage of the semiconductor laser 17, feedback values of output values from various high-voltage power supplies, and the like are input to the analog input of the CPU 101. An input from a thermistor provided in the fixing device 39 performs on / off control or phase control of the fixing heater so that the temperature of the fixing portion becomes constant. The photosensor input is used to control the toner density by inputting a photopattern created at a predetermined timing by a phototransistor and detecting the density of the pattern to control the on / off of the toner supply clutch. . Also,
The toner end is also detected by this density detection.

Next, the operation-related control is shown in FIG.
This will be described with reference to 0. The main CPU 102 controls a plurality of serial ports and a calendar IC, and the plurality of serial ports includes a CPU 1 for sequence control.
01, power supply monitoring unit 97, operation unit 1
06, the editor 107, the scanner control circuit 62, the application unit 67, etc. are connected.

The operation unit unit 106 has a display for displaying the operator's key input and the status of the copying machine, and informs the main CPU 102 of the key input information by serial communication. Based on this information, the main CPU 102 determines whether the indicator of the operation unit unit 106 is lit or blinks, and serially transmits to the operation unit unit 106. Operation unit 10
6 turns on, off, or blinks the display according to the information from the main CPU 102. The main CPU 102 further determines the operating conditions of the machine from the obtained information and performs sequence control at the start of copying.
The information is transmitted to 01.

In the scanner control circuit 62, as shown in FIG. 6, scanner servo motor drive control and image processing,
Information regarding image reading is serially transmitted to the CPU 102, and an interface between the ADF control board 69 and the sequence CPU 101 is performed.

The application unit 67 is an external device (facsimile, printer, etc.) and the main CPU 10.
It is an interface between the two and exchanges preset information contents. The editor 107 is a unit for inputting editing functions, and image editing data (masking, trimming, image shift, etc.) input by the operator.
Is serially transmitted to the CPU 102. Calendar IC10
8 stores the date and time, and can be called by the CPU 102 at any time. Therefore, the power of the machine is turned on by displaying the current time on the display of the operation unit 106 and setting the on time and off time of the machine. -It is possible to control the turning off by a timer.

A signal switching gate array 109 is also provided. This signal switching gate array 109 is C
In response to a select signal from PU 102, page memory 1
The image data (DATA0 to 7) stored in 10 and various synchronization signals are output in the following three directions. First
Is output from the scanner control circuit 62 to the image control circuit 111. In this case, the image signal transferred from the scanner as 8-bit data (however, it can be 4-bit or 1-bit) is used as the laser beam scanner unit 1
This is output to the image control circuit 111 in synchronization with the synchronization signal PMSYNC from 05. The second is output from the scanner control circuit 62 to the application unit 108. In this case, the image signal transferred from the scanner as 8-bit data is transferred to the application unit 108.
Output in parallel. Application unit 108
Then, the input image data is output to an output device such as a printer connected to the outside. The third is output from the application unit 108 to the image control circuit 111. In this case, the image signal transferred from the input unit externally connected to the application unit 108 with 8-bit data (however, it can be 4 bits or 1 bit) is used as the laser beam scanner unit 10.
The signal is output to the image control circuit 111 in synchronization with the synchronization signal PMSYNC from 5. When the image signal from the outside has 4 bits or 1 bit, it is necessary to perform a process of converting it into 8-bit data.

The CPU 102 has a ROM 112.
And a RAM 113 are connected. RAM1 here
Reference numeral 13 is a non-volatile memory to which a backup battery (not shown) is connected. As a result, the data contents are not lost even when the power is turned off. Therefore, the count values of various counters such as the total copy number counter and the jam counter, the illuminance setting value of the light source 5, the setting values such as the temperature setting value of the fixing heater, etc. I can remember it. These data can be changed using a numeric keypad or the like as needed.

Next, the structure of the image scanner unit is shown in FIG.
This will be described with reference to 1. The analog image signal output from the CCD image sensor 12 is an image preprocessor IP.
The signal processing circuit 121 inside the P73 amplifies and corrects the light amount, and the A / D converter 122 converts the signal into a digital multilevel signal. This signal is subjected to correction processing by the shading correction circuit 123, and the image processing unit IPU
It is output to 74.

The IPU 74 is constructed as shown in FIG. That is, the image signal applied to the IPU 74 is emphasized in the high frequency range by the MTF correction circuit 124, and the scaling circuit 125.
Is electrically scaled (according to magnification data in the main scanning direction set by the scanner control circuit 62) by the γ conversion circuit 12
6 is applied. The γ conversion circuit 126 performs conversion processing so that the input characteristics are optimized according to the characteristics of the machine, and the image signal output from the γ conversion circuit 126 is predetermined by the switch 128 of the data depth switching mechanism 127. Is converted to the quantization level of. This data depth switching mechanism 1
Reference numeral 27 includes a 4-bit conversion circuit 129, a binarization circuit 130, a dither circuit 131, and a switch 132, and FIG.
.. are switched to three data types as shown in (c). First, the 4-bit conversion circuit 129 outputs 4-bit data as shown in FIG.
Then, the input 8-bit multivalued data is converted into binary data by a preset fixed threshold value, and 1-bit data as shown in FIG. 13C is output. The dither circuit 131 produces an area gradation with 1-bit data as shown in FIG. The switch 128 selects one of these three data types and outputs it as DATA0-7.

The scanner control circuit 62 follows the instructions from the CPU 102 to stabilize the ballast 70 and the timing control circuit 13.
3. It controls the magnification changing circuit 125 and the scanner drive motor 71 in the IPU 74. The ballast 70 is the scanner control circuit 6
According to the instruction from 2, the light source 5 is turned on / off and the light amount is controlled. The rotary encoder 13 is attached to the drive shaft of the motor 71.
4 are connected, and the position sensor 135 detects the reference position of the sub-scanning drive mechanism.

The timing control circuit 133 outputs each signal according to the instruction from the scanner control circuit 62. That is,
When reading is started, a transfer signal for transferring one line of data to the shift register and a shift clock pulse for outputting the data in the shift register bit by bit are given to the CCD 12. The pixel synchronization clock pulse CLK, the main scanning synchronization pulse LSYNC, and the main scanning effective period signal LGATE are output to the image reproduction system control unit. This pixel synchronization clock pulse CLK is a signal almost the same as the shift clock pulse given to the CCD 12,
The main scanning synchronization pulse LSYNC is used for the image writing unit 15
Main scanning synchronization signal PMSYNC output from the beam sensor of
Although the signal is almost the same as that of the pixel synchronization clock pulse C
It is output in synchronization with LK. Further, the main scanning effective period signal LGATE is a signal which becomes H level at the timing when the output data DATA0 to DATA7 are regarded as effective data. Incidentally, in this embodiment, the CCD 12 outputs 4800 bits of effective data per line.

When the scanner control circuit 62 receives a reading start instruction from the CPU 102, the light source 5 is turned on, the scanner drive motor 71 is started to be driven, the timing control circuit 133 is controlled, and the reading by the CCD 12 is started. Further, the sub-scanning effective period FGATE is set to the H level. This signal FGATE becomes L level when the time required to scan the maximum reading length (in this example, the dimension in the longitudinal direction of A3 size) in the sub-scanning direction after being set to H level.

By the way, the memory system 14 of the present embodiment.
1 will be described with reference to FIG. The image signal from the CCD 12 is output as 8-bit data through the IPP 73 having the functions of shading correction, black level correction, and light amount correction. This data is the multiplexer (MUX) 1
Selected in 42, it has a spatial frequency high-frequency emphasis function (MTF correction function), a speed conversion function (variable magnification function), a γ conversion function, and a data depth conversion function (8 bit / 4 bit / 1 bit conversion function). It is processed by the IPU 74 and output to the printer section PR through the multiplexer 143.

In the case of a system having a frame memory for image data, as shown in FIG. 15, the image data from the IPU 74 is temporarily stored in the memory device (MEM) 144.
In the memory device 144, and when necessary, it is taken out of the memory device 144 and output to the printer PR. Also, I
It is also common to output the image data from the PU 74 to the printer PR and at the same time store the image data in the memory device 144 and copy the second and subsequent sheets with the image data from the memory device 144.

In this respect, in the present embodiment, the data flow as shown in FIG. 16 is arranged so that both the data processed by the IPU 74 and the raw data can be taken into the memory device 144. Has been done. That is, FIG.
The data flow can be changed by switching the three multiplexers 142, 145, 143 shown in FIG. For example, a single scanner scan can be used to print multiple IPs.
When outputting a copy in which the parameters of U74 are changed, the multiplexer 142 is set to A when scanning the scanner.
Side, multiplexer 145 to B side, multiplexer 14
3 is set to the A side and the first sheet is output. At this time, the raw data is stored in the memory device 144 through the multiplexer 145. For the second and subsequent sheets, the multiplexer 142 is set to the B side, the data from the memory device 144 is input to the IPU 74, and the multiplexer 143 is output to the printer PR. At this time, the parameters of the IPU 74 are changed every time one copy is made. It can be achieved by such a procedure.

When holding compact data such as 1-bit data, the multiplexer 145 is set to A
The output of the IPU 74 is taken into the memory device 144. In this case, the printer PR switches to the binary data (1 bit) mode and performs the copy operation.

Signals EXTIN and EXT shown in FIG.
UT is an image data input / output signal from the external storage device 75.

By the way, as the memory device 144, for example, one having a structure as shown in FIG. 17 is used. That is, the compressor (COMP) 146 and the expander (EX
P) 147 and before and after the memory unit 148,
In addition to actual data, compressed data can be stored. In this configuration, the compressor 146 must operate at scanner speed and the decompressor 147 must operate at printer speed. Actual data in memory unit 14
8 to store the data in the multiplexers 149 and 15
0 is set to the A side, and when compressed data is used, it is set to the B side.

Here, the memory unit 148 is constructed, for example, as shown in FIG. That is, FIG.
The data width converters 155, 156 are provided at the input and output of the memory block 157 in order to handle the three image data types shown in (a) to (c) and code data which is compressed data. Further, the direct memory controllers (DMC) 158 and 159 write data into or read data from a predetermined address of the memory block 157 according to the number of packed data and the memory data width.

The data type of the image data shown in FIG. 19 will be described. Normally, the speed of image data from the scanner or to the printer is constant regardless of 8-bit data, 4-bit data or 1-bit data. That is, the period of 1 pixel is fixed in the device.
In the device of this embodiment, 1-bit data, 4-bit data, 8-bit data and M
It is defined by SB justification. The blocks for packing and unpacking this data to the data width (16 bits) of the memory block 157 are the data width converters 155 and 156. By packing, the memory block 157 can be used according to the data depth.
44 can be effectively used.

The compressor 146 shown in FIG.
Instead of using the decompressor 147 and the expander 147, the pixel process unit (PPU) 161 may be arranged outside the memory unit 148 as shown in FIG. The PPU 161 is a unit that expresses a logical operation (for example, AND, OR, EXOR, NOT) between image data, and has a function of calculating memory output data and input data and outputting the same to the printer PR, and memory output and input data. (For example, scanner data) is calculated and stored again in the memory unit 148. Switching between the output printer PR and the memory unit 148 is performed by the multiplexers 162 and 163. This function is generally used for image synthesis, and is used, for example, to place overlay data in a memory unit and overlay the scanner data.

Next, an example of a configuration for storing image data using the external storage device 75 will be described with reference to FIG. First, copy the image data to floppy disk 16
When the data is stored in 5, the data is output from the EXTOUT to the floppy disk controller (FDC) 168 controlled by the file controller 167 through the interface 166,
The floppy disk 165 on the floppy disk drive (FDD) 169 is stored. Under the control of the file controller 167, a hard disk controller (HDC) 170, a hard disk drive (HDD)
There is also 171, and reading / writing on the hard disk is also possible. Specifically, the normally used format data and overlay data are stored in the HDD 171 side so that they can be used as needed.

FIG. 22 shows a configuration capable of 100% recovery even when the processing speeds of compression and decompression are not in time. The memory unit 148 stores data and image data that are compressed at the same time as the scanner scan. The incoming data is stored in different memory areas, but the compressed data is directly input to the decompressor 147 and decompressed. All data for one page is in memory unit 14
If the processing time of the compressor 146 and the decompressor 147 ends normally by the time of entering 8, the compressed data memory area remains and the raw data area is canceled. If the error detection circuit 151 has the compressor 146 or the decompressor 1
When the error signal from 47 is detected, the compressed data area is immediately canceled and the raw data is adopted.

The memory management unit (MMU) 175 is a unit for controlling the memory unit 148 so that two input data and one output data can be simultaneously input / output to / from the memory unit 148. By verifying compression and decompression in real time, high speed and reliability and effective utilization of memory area are ensured. In this embodiment,
In such a configuration, the memory management unit 175 allows dynamic allocation of the memory area, but two memory units for raw data and compressed data may be provided.

In any case, the configuration shown in FIG. 22 must be compatible with the number of stored pages and the printing speed such that a plurality of pages are stored and output to the printer in real time as in electronic sorting. Suitable for various applications.

Next, a power supply monitoring operation using the uninterruptible power supply 91 will be described. First, the power supply monitoring unit 9
7, an AC voltage drop detection circuit (AC voltage drop detection means) 200 as shown in FIG. 23 is provided.
That is, a full-wave rectification circuit 201 including four diodes is connected to the AC power supply 90, and an analog comparator 204 is connected to the rectification output terminal thereof via voltage dividing resistors 202 and 203. This comparator 204
A variable resistor 205 for setting the reference voltage Vref is connected to the reference input terminal of the. Comparator 204
A re-trigger type monostable multivibrator 206 that outputs an AC voltage drop detection signal is connected to the output side of the.
Here, the monostable multivibrator 206 has a variable resistor 207 and a capacitor 208 for setting the detection time.
Are connected.

In such a configuration, when the voltage V ₀ of the AC power source 90 drops for one cycle as shown in FIG. 24 (a), the waveform rectified by the full-wave rectifier circuit 201 is shown in FIG. 24 (b). The voltage V ₁ shown in FIG. The output voltage V ₂ of the comparator 204 having such a rectified voltage V ₁ as a positive input has a pulse waveform as shown in FIG.
The output is not output in the portion where the voltage drops below the reference voltage Vref. The re-trigger type monostable multivibrator 206 that receives such a voltage V ₂ is re-triggered in the portion where the output of the comparator 204 is continuously output when the AC voltage V ₀ is equal to or higher than the set value, so that the output V ₃ is at the H level. However, if the output V ₂ of the comparator 204 is dropped for a predetermined time t or longer due to a voltage drop, the monostable multivibrator 206 is not retriggered and an L level output is output as an AC voltage drop detection signal. Here, the variable resistor 205 can set the lowering level to be detected by the ratio to the peak value of the sine wave. The output time of the monostable multivibrator 206 is determined by the variable resistor 207. If it is set too long, it will not be detected even if the voltage drops for a short time, but if it is set too short, it will be possible to detect even the voltage drop for a short time. The shortest is a half cycle. The output V ₃ (AC voltage drop detection signal) from the monostable multivibrator 206 is input to the external interrupt terminal of the CPU in the uninterruptible power supply 91 as described later.

Such an AC voltage drop detecting circuit 200
Has a feature that a decrease in the AC voltage V ₀ can be promptly detected, a decrease level to be detected can be set, and a decrease duration time to be detected can be set.

Sequence control at the time of power interruption using the uninterruptible power supply 91 will be described with reference to the timing chart of FIG. First, when the commercial power supply 90 is cut off due to a power failure or the like, the uninterruptible power supply 91 detects it by the power supply monitoring circuit 97, and supplies the power in place of the commercial power supply 90 by the storage battery and the DC / AC converter. at the same time,
A power cutoff signal is generated and the CPU in the uninterruptible power supply 91 is notified of this. The CPU controls each element to execute a special sequence called "shutdown sequence" in response to the power-off signal. When the shutdown sequence ends, the end signal is output to the uninterruptible power supply 91.
To notify. The uninterruptible power supply 91 that has received the end signal stops the power supply, and the entire system is turned off at this point.

The shutdown sequence will be described here. At the time of executing this special sequence activated by the power cutoff signal, the commercial power supply 90 is cut off and power is supplied from the storage battery of the uninterruptible power supply 91. The purpose of performing such a special sequence is to reduce power consumption and extend the power supply time by the storage battery. Complete the discharge so that the transfer paper is not left in the machine during copying. The photoconductor 1 is designed so as not to adversely affect the photoconductor 16.
Complete the initialization of 6. When the power supply is restarted, various information is saved in the non-volatile memory 113 so that the previous job can be easily continued. Notify users that commercial power has been cut off. When necessary processing is completed, stop power supply from the storage battery to prevent deterioration due to over-discharge of the storage battery. Is.

Each item will be described below. First,
The reduction of power consumption will be described. Generally, in the copying machine as in this embodiment, the largest power consumption element is the fixing heater in the fixing device 39. Specifically, since the toner on the transfer paper is heated and pressure-fixed, the temperature is 1
The temperature is controlled to about 80 ° C. As the fixing heater, a halogen heater of about 800 W is used. Further, since the fixing heater has a relatively large heat capacity, the fixing temperature can be maintained for several copies even after the power supply is stopped. Further, there is a temperature range in which the fixing property cannot be guaranteed but paper can be passed without damaging the fixing roller (see FIG. 26). By utilizing such characteristics, it is possible to discharge the transfer paper inside the machine without energizing the fixing heater and to reduce power consumption. Therefore, in the shutdown sequence, the fixing heater is turned off.

Next, the remaining paper discharge will be described.
One of the major reasons for mounting the uninterruptible power supply 91 is to prevent transfer paper from being left inside the machine when a power failure occurs. That is, removing the residual paper in the machine is the same as the processing of the jammed paper, even though it is caused by the power failure, and is one of the most unpleasant operations for the user. Therefore, in the shutdown sequence, the operation of the elements involved in the conveyance / discharge is continued until the discharge of the transfer paper inside the machine is completed. More specifically, when the shutdown process is started, the states of the transfer paper inside the machine are as follows: a state before the image is not yet transferred, a state during the image transfer, and a state after the image transfer is completed. There can be If it is limited to discharging, it is sufficient to turn off all process means to reduce power consumption and distribute all the power to discharging operation, but discharging the transfer paper in a state where the image is interrupted in the middle As a result, the user may feel uncomfortable and may misunderstand that an abnormal image is generated. Therefore, here, considering the reduction of power consumption, image guarantee is also made, and if the image transfer is completed, it can be fixed without any problem, so it is a normal copy. Although it is made into a copy, fixed, and ejected, if the image has not yet been placed, it is not copied and a blank sheet is ejected as an invalid copy.

The initialization of the photoreceptor will be described. As described above, the transfer paper is discharged so that it does not remain in the machine, but if the photoconductor 16 is also left without performing the predetermined sequence, it may cause fluctuations in characteristics and poor cleaning. . Therefore, even if the transfer paper does not remain in the machine, the photoconductor 16 is always initialized, and the elements required for the initialization are driven. In particular,
The charged portion on the photoconductor 16 is discharged by the discharge lamp 33, and the remaining toner portion is cleaned and removed by the cleaning device 32. Furthermore, N / P
Due to the process, a reverse bias (+) is applied to the developing bias in the non-charged portion so as to prevent toner adhesion.

The power failure notification to the user will be described. Since the shutdown process is a special operation, the repeat copy is interrupted without accepting the user's operation, but if no display is made at this time, the user may feel anxiety / distrust. However, the display consumes a lot of power, so I want to turn it off if possible.
Also, considering the operation at the time of power failure, it is not preferable to add a lot of display to the image. Therefore, here, during the shutdown process, a specific display, for example, only the power failure display 202 shown in the operation unit 201 of FIG. 27 is lit and all other lights are turned off.

Further, the prevention of over-discharge will be described. Continuing the normal power supply by the uninterruptible power supply 91 after the shutdown ends leads to early consumption of the storage battery and deterioration due to over-discharge. Therefore, here, an end signal is sent to the uninterruptible power supply 91 at the end of the shutdown process, and the power supply is stopped except for the power failure display section 254 and the FAX receiving section. As a result, the use of the storage battery is suppressed to a necessary minimum, and deterioration due to overdischarge is prevented.

The above contents are shown in the timing chart of FIG. 28, the copy control flowchart of FIG. 29, and the shutdown process general flowchart of FIG.

In such a presupposed configuration / operation,
In this embodiment, the uninterruptible power supply 91 is improved and devised as shown in FIG. 1 so that useless shutdown sequence operation is not performed. Here, option 1 (for example, A
It is assumed that the system configuration includes the DF2) and the option 2 (for example, the sorter 3). In the uninterruptible power supply 91, a CPU 260 and a storage battery 261 which function as a momentary interruption simulation means and a control means are installed.
For the CPU 260, the copying machine body 1, the ADF 2,
An interrupt terminal INT1 for taking in a reset signal from each of the sorters 3 via the AND gate 262 is provided. Further, an interrupt terminal INT0 for taking in a signal from the power supply monitoring unit 97 including the AC voltage drop detection circuit 200 is also provided. Further, the uninterruptible power supply 91 is provided with a switch 263 for switching under control of the CPU 260 whether to supply power from the AC power supply 90 to the load or to supply power from the uninterruptible power supply 91, that is, the storage battery 261 to the load.

In such a configuration, for example, ADF2
When the main body 1 of the copying machine is installed with the sorter 3 and the sorter 3 installed and the instantaneous interruption simulation mode is selected and designated, the CPU 2
Under the control of 60, the instantaneous interruption simulation mode process is performed. This process is a process for measuring the reset time in order to obtain the time from the voltage drop or interruption of the AC power supply 90 to the start of the shutdown sequence operation. First, the mode setting is notified from the main CPU 102 to the CPU 260 in the uninterruptible power supply 91 through the operation unit 201, and the CPU 260 is notified by the switch 263.
Are both open (contacts a and b are open),
The power supply to the load is momentarily cut off, and the CPU 260
Start the internal timer. Then, it waits until a reset signal is input to the external interrupt terminal INT1. When any one of the copying machine main body 1, the ADF 2 and the sorter 3 goes down, the interrupt terminal INT1 is interrupted. Therefore, by measuring the reset time until this interrupt occurs, the time until the system goes down due to a power failure can be known.

When the measurement of the reset time is completed, the CPU 260 in the uninterruptible power supply 91 closes the contact a side of the switch 263 to allow the AC power supply 90 to supply power to the load as usual, and to measure the main CPU 102 side. Notify the end of the mode (instantaneous interruption simulation mode). The CPU 260 also stores a time obtained by subtracting a predetermined time from the measured reset time in a non-volatile RAM (not shown) as the time from the voltage drop or interruption of the AC power supply 90 to the start of the shutdown sequence operation.

Therefore, the processing when the voltage drop or interruption of the AC power supply 90 occurs during the copy operation, for example, will be described. When such a voltage drop or interruption is detected by the power supply monitoring unit 97, the signal indicates the external interrupt terminal INT of the CPU 260 in the uninterruptible power supply 91.
Input to 0. In response to this, the CPU 260 immediately informs the main CPU 102 side that the power supply is abnormal, but does not immediately execute the shutdown sequence. That is, if the AC power supply 90 does not recover after waiting for the time stored in the non-volatile RAM, the CPU 260 can determine this by checking the level of the external interrupt terminal INT0, and if it is at L level, it is abnormal. It remains as it is, and if it is at the H level, it returns to the normal state.), The contact a side of the switch 263 is opened and the contact b side is closed to supply power from the storage battery 261 to the load, and the main CPU 102 To the start of the shutdown sequence. This allows the main CPU
102 executes the shutdown sequence as described above.

In other words, if it is in the standby mode, only the current mode is saved. However, if the copy operation is in progress, the remaining modes are saved after the currently executed process is completed. Then, the CPU 260 is notified that the evacuation process is completed, and the power failure is displayed.
After that, the CPU 260 switches the switch 26 after a predetermined time elapses.
The contact b side of No. 3 is opened and the contact a side is closed to wait for the AC power supply 90 to return. In addition, when the power supply abnormality does not occur during the standby, the loads other than the DC power supply are turned off to perform the shutdown sequence operation (this is the main CPU.
102 by issuing an off instruction to another load).

As described above, according to the present embodiment, the power supply operation by the uninterruptible power supply 91 is not started immediately even if the power supply voltage drops or is interrupted, and the reset time obtained by the instantaneous interruption simulation is referred to. Since the shutdown sequence operation is started only when the power supply does not return after a predetermined time elapses, the shutdown sequence operation is not performed even when the power supply recovers quickly and the unnecessary power of the storage battery 261 is consumed. It can prevent consumption. Further, such a time setting is automatically measured at the stage when the system is installed by the instantaneous interruption simulation process, so that the setting is not troublesome and accurate.

Next, an embodiment of the invention described in claim 2 will be described with reference to FIG. The same parts as those shown in the above-mentioned embodiments are designated by the same reference numerals, and the description thereof is omitted (the same applies to the following embodiments). In this embodiment, each load 1, 2, 3
Regarding the DC power supply unit part and the other part, when the AC voltage drop circuit 200 detects a voltage drop or the like and executes the shutdown sequence, the detection time point of the voltage drop or the like is a copy operation or a standby state. The target load is switched depending on whether or not. For this reason, switches 264a, 264b, 264c serving as supply destination switching means are provided on the power input sides of the loads 1, 2, 3 and are configured to be switched and controlled by the CPU 260.

That is, when a drop in the power supply voltage or the like is detected during the copy operation, each switch 264a, 264b, 2
Although the contact a side of 64c is kept closed, power is supplied from the uninterruptible power supply 91 to all of the loads 1, 2, and 3 (DC power supply unit and other loads) to execute the shuttown sequence. When a drop in the power supply voltage or the like is detected during standby, each switch 264a, 264b, 264
The contact b side of c is closed, and each load 1,
The shutdown sequence for supplying electric power only to the DC power supply units in 2 and 3 is executed. That is, since the transfer paper remains and the like does not occur in the copying machine main body 1 in the standby state, it is not necessary to operate the paper discharge system or the like (there is no need to perform the jam processing later), and thus the shutdown sequence processing is performed. As a result, power need only be supplied to the DC power supply unit, and useless power consumption of the uninterruptible power supply 91 is prevented.

Further, an embodiment of the invention described in claims 3 and 4 will be described with reference to FIGS. 32 and 33. In this example,
Even if a power failure or the like occurs, if it is on standby, the uninterruptible power supply 91 does not supply the power, and the power supply to the load is completely turned off. For this reason, a relay contact 266 as a power supply switching means controlled to be opened and closed by the CPU 260 in the uninterruptible power supply 91 is provided on the power supply line between the uninterruptible power supply 91 and the load, here the copying machine main body 1. Therefore, power is not supplied from the uninterruptible power supply 91 during standby without concern about transfer paper remaining, and wasteful power consumption is prevented.

If the relay contact 266 is immediately opened to turn off the power supply here, even if the operator sets the mode immediately before the power failure, the mode will disappear and the power must be reset after the power is restored. I have to. In particular, when the power failure is restored in a short time, or in the case of an instantaneous power failure that the user does not notice, if the setting mode is erased, it gives a feeling of malfunction.
In this respect, in the present embodiment, the opening of the relay contact 266 is controlled through the delay means 267, so that the relay contact 266 is not immediately turned off even when a power failure occurs, and when the power supply is quickly restored due to an instantaneous power failure or the like. The setting mode will be maintained.

By the way, regarding the maintenance of the setting mode,
It may be desired to be maintained not only in the case of such a momentary power failure but also during a longer power failure. To this end, the power switch 268 that normally terminates the copy operation.
It is only necessary to distinguish between the power-off by turning off the power and the forced power-off due to a power failure or the like, and at the time of the forced power-off, the mode set at that time may be stored in the non-volatile memory (mode storage means). Therefore, in this embodiment, the power switch 26
8 is provided with the power switch determination means 269 for detecting the open / closed state, and when a voltage drop is detected by the AC voltage drop detection circuit 200 with the power switch 268 closed, under the control of the CPU 260, the current time is detected. The setting mode is stored in the nonvolatile memory, and the setting mode is reproduced as it is after the power is restored.

A modification is shown in FIGS. 34 and 35. In this modification, when a power failure is detected by the AC voltage drop detection circuit 200, the operation unit 10 is detected by this detection signal.
The copy key on 6 is controlled not to be accepted. According to this, although the copy key is not accepted, the power is supplied from the uninterruptible power supply 91, so that the set mode is maintained. Further, since a new copy operation is prohibited, useless power consumption of the uninterruptible power supply 91 (discharge of the storage battery 261) is also prevented.

Further, an embodiment of the invention described in claims 5 and 6 will be described with reference to FIG. In this embodiment, by using the uninterruptible power supply 91, the breaker is prevented from dropping due to a temporary increase in current. First, when there are a unit 1 (for example, a copying machine main body 1), a unit 2 (for example, ADF 2), and a unit 3 (for example, a sorter 3) as loads using an AC power supply as a power source, each of these units 1, 2, 3 Current detection means (consumption current detection means) 27 for individually detecting the current (consumption current) flowing with respect to
0, 271, 272 are provided. The detection results of the current detecting means 270, 271, 272 are taken into the control circuit 273. Further, on the input side of the uninterruptible power supply 91, current limiting means 274 for limiting the input current from the AC power supply 90 to the uninterruptible power supply 91 is provided. Furthermore, the AC power supply 90, the uninterruptible power supply 91, and each unit 1, 2, 3 (current detection means 270, 271, 27)
2), switches 275, 276, 277 are provided as a source switching means for switching between the AC power source 90 and the uninterruptible power source 91 as a power source. These switches 275, 276, 277 are switched and controlled by the control circuit 273.

In such a structure, basically, electric power is supplied from the AC power source 90 to each unit 1, 2, 3. At this time, the current consumption consumed by each of the units 1, 2, 3 is detected by the current detection means 270, 271, 272, taken into the control circuit 273, and the total sum of the detected current consumption is checked. When this total exceeds a certain value, the control circuit 273 switches the switches 275, 276, 2
77 is switched to control the power supply source to any of the units 1, 2 and 3 from the AC power supply 90 side to the uninterruptible power supply 91.
Switch to the side. Here, the uninterruptible power supply 91 is charged in a state where the input current is limited through the current limiting means 274, and any one of the units 1, 2 and 3 is used as a load by switching any one of the switches 275, 276 and 277. When connected, the storage battery 261 discharges and supplies power to the connected load. Here, the input current of the uninterruptible power supply 91 is limited by the current limiting means 274, and a value higher than the set current does not flow. That is, according to the present embodiment, when an input current exceeding the rating flows, the uninterruptible power supply 91 compensates for the excess, so that the breaker can be prevented from operating immediately, and is suitable for a temporary increase in current. Can be dealt with.

In this way, the switches 275, 276, 27
When switching the power supply source by switching 7, switching may be prioritized according to the power consumption of the units 1, 2, 3. For example, regarding the units 1, 2, and 3, when the power consumption is in the order of unit 1> unit 2> unit 3, when a temporary increase in current is detected in the unit 1, 2 is operated by the uninterruptible power supply 91, and when a temporary current increase is detected in the unit 2, the unit 1
May be operated by the uninterruptible power supply 91. By giving such a priority order, it is possible to surely prevent the rating from being exceeded by burdening the uninterruptible power supply 91 with a larger load.

FIG. 37 shows a modification. In this variation,
The power supply to the units 1, 2 and 3 is always performed from the AC power supply 90 through the uninterruptible power supply 91, and the current detection means 278 for detecting the current consumption of the entire units 1, 2 and 3 is provided. Uninterruptible power supply 9
A switch 279 for connecting and disconnecting the connection with the AC power source 90 is provided on the input side of 1.

In such a configuration, normally, the power from the AC power source 90 is supplied to each unit 1, 2, 3 through the uninterruptible power source 91, and the total current consumption at that time is detected by the current detecting means 278. . When this detected current exceeds a certain value, the control circuit 273 opens the switch 279 and disconnects the uninterruptible power supply 91 from the AC power supply 90. That is, when the load is large and the input current is likely to exceed the rated current of 15 A, the uninterruptible power supply 91 is disconnected from the AC power supply 90 to operate only by the uninterruptible power supply 91, so that the breaker does not break and the predetermined breakage occurs. The operation can be continued.

Another modification will be described with reference to FIG. In this modification, the unit 28 using the DC power source 280 as a power source
In consideration of the case where the load is 1, 282, 283, the current detecting means 284, 28 for detecting the consumption current of each of the units 281, 282, 283 is considered on the input side.
5,286 are provided. Further, a current limiting unit 287 is provided at the subsequent stage of the DC power source 280. on the other hand,
A DC power supply 289 with a battery 288 is provided in parallel with the DC power supply 280, and charging current limiting means 290 is provided on the input side thereof. Furthermore, each unit 281,
The DC power supply 280 is used as the power supply source for 282 and 283.
There are provided switches 291, 292, 293 for switching by the control circuit 273 whether to use only the DC power supply 280 or both the DC power supply 280 and the DC power supply 289 with a battery.

In such a configuration, the switches 291, 292, 293 are normally off and the unit 28
Electric power is supplied from the DC power supply 280 to the 1, 282 and 283. The current consumption at this time is the current detecting means 28.
4,285,286. When the total sum of the detected current consumption exceeds a certain value, the control circuit 2
Reference numeral 73 closes the switch 291, 292 or 293 to the corresponding unit 281, 282 or 283, and supplies the power to the unit to both the DC power source 280 and the DC power source 289 with a battery. That is, the DC power supply 28
When the output current from 0 is limited by the current limiting means 287 and is insufficient, the shortage is compensated for by the DC power source 289 with battery. At this time, the charging current limiting means 290 limits the charging current of the battery-equipped DC power supply 289. In this way, when the load becomes large and the input current is about to exceed the rated current of 15 A, the breaker is prevented from being cut off by supplying the insufficient electric power from the DC power supply 289 with a battery. Even in this case, since the charging current limiting means 290 is provided for the DC power source 289 with a battery, the total input current does not exceed 15A.

In this modification also, the switch 2
It is also possible to give priority to the switching of 91, 292, and 293.

Next, an embodiment of the invention described in claims 7 and 9 will be described with reference to FIG. In this embodiment, the power of the uninterruptible power supply 91 is used to heat the fixing heater. First, in this embodiment, the fixing heater is divided into the first fixing heater 294a and the second fixing heater 294b. Here, a switch 295 for switching the power supply from the AC power supply 90 and the power supply from the uninterruptible power supply 91 to the first fixing heater 294a is provided. Further, a switch 296 for connecting / disconnecting the uninterruptible power supply 91 to the second fixing heater 294b is provided.
These switches 295 and 296 are controlled by the main control board 61 which functions as a power supply control means.

In such a structure, when the power is turned on, the switch 295 is closed on the terminal a side and the first fixing heater 2
AC power is supplied to 94a from the AC power supply 90, and the switch 296 is closed to cause the second fixing heater 294b.
Is supplied from the uninterruptible power supply 91. When the temperature of the fixing roller reaches a certain temperature, the switch 296 is opened, and the AC power source 90 for the first fixing heater 294a is opened.
Only the power supply by That is, uninterruptible power supply 9
Unnecessary power consumption of 1 is prevented. Thus, when the fixing heaters 294a and 294b rise, the AC power source 9
Since both 0 and the uninterruptible power supply 91 are used, the rise time is short and the useless waiting time can be shortened under the condition that the power distribution is restricted. In particular, since the two fixing heaters are configured, the AC power supply 90 and the uninterruptible power supply 91 may be separately supplied with power, and the circuit configuration is simplified.

By the way, during the copying operation after the fixing heater is activated, basically, the first fixing heater 294a is basically operated.
The fixing temperature is controlled only by energizing the. Then,
If a predetermined condition is satisfied even during copying, the switch 296 is closed and the second fixing heater 294b is also energized. Here, the predetermined condition is, for example, a case where the temperature of the fixing roller drops below a predetermined temperature due to continuous copying, and the fixing temperature is maintained by energizing the second fixing heater 294b by the uninterruptible power supply 91. . Therefore, even during continuous copying, it is possible to prevent the temperature of the fixing roller from decreasing and it is not necessary to take a countermeasure such as slowing down the copying speed.

Further, an embodiment of the invention described in claims 8 and 10 will be described with reference to FIG. This embodiment is basically the same as the above embodiment, but one fixing heater 294 is used and they are combined by the combining circuit 297 (AC power supply 90+
The power from the uninterruptible power supply 91) or the power from only the AC power supply 90 is applied to the fixing heater 294.
A switch 298 for this purpose is provided before the fixing heater 294.

In such a structure, the switch 298 is activated until the fixing roller reaches a constant temperature when the power is turned on.
Is switched to the terminal b side, and the electric power obtained by combining the AC power supply 90 and the uninterruptible power supply 91 by the combining circuit 297 is applied to the fixing heater 294, so that the fixing roller is quickly raised to a predetermined temperature. When the temperature reaches the predetermined temperature, the switch 298 is switched to the terminal a side, and the fixing heater 294 is energized only by the AC power source 90.

This state is basically maintained even during the copying operation. However, as in the case described above, if a predetermined condition is reached such that the temperature of the fixing roller drops below a predetermined temperature due to continuous copying, for example. , The switch 298 is switched to the terminal b side again, and the combined electric power is supplied,
The temperature of the fixing roller is maintained and returned to the predetermined fixing temperature, and the switch 298 is switched to the terminal a side.

In the case of this embodiment, although the synthesizing circuit 297 is required, only one fixing heater 294 is required.

[0119]

Since the present invention is constituted as described above, according to the invention of claim 1, the reset time at the time of instantaneous interruption is measured in advance by the instantaneous interruption simulation means, and the AC voltage drop detecting means. Even if a voltage drop or interruption of the AC power supply is detected by, the evacuation process by the uninterruptible power supply is not started immediately, but the evacuation process is performed only when the power supply is not restored even after the elapse of a predetermined time within the reset time. Therefore, even if the AC power supply is immediately restored, wasteful processing by the uninterruptible power supply is not performed, and wasteful power consumption of the uninterruptible power supply can be prevented, and even if it takes time to restore. Because the evacuation process is performed within the reset time, the recovery of the uninterruptible power supply system is secured without recovering the transfer paper jam state etc., and the reset time at this time can also be set. Because according to the cross-sectional simulation can be automatically to assume precise.

According to the second aspect of the present invention, even if the voltage of the AC power supply drops, if the image is being formed, the uninterruptible power supply supplies power to all the units to perform the image forming operation at that time. However, in the standby mode, power is supplied only from the uninterruptible power supply to the DC power supply unit, so wasteful power consumption of the uninterruptible power supply is prevented and the minimum necessary processing by the DC power supply unit is performed. Only can be secured.

According to the third aspect of the present invention, even if an uninterruptible power supply is provided, power is supplied to the image forming apparatus as long as the occurrence of a voltage drop in the AC power supply is in standby without fear of transfer paper remaining or the like. Since it is turned off, it is possible to surely prevent wasteful power consumption of the uninterruptible power supply.

At this time, according to the invention described in claim 4, when the power supply is turned off, the open / closed state of the power switch is checked. Since it is recognized as the latter one and the setting mode is memorized, there is no trouble of resetting the mode after the power is restored.

According to the invention described in claim 5, when the detected current consumption exceeds a certain value, the power supply to the unit is switched from the AC power supply to the uninterruptible power supply. When the current flows, the uninterruptible power supply compensates for the excess, and it is possible to prevent the breaker from operating unnecessarily due to a temporary increase in current.At this time, the input current of the uninterruptible power supply is set by the current limiting means. It does not flow more than the current.

In this case, according to the invention as set forth in claim 6, since the priority of switching the power supply destination is given according to the current consumption in each unit, the uninterruptible power supply is supplied to the one with the largest current consumption. By substituting the power supply to the device, it is possible to more reliably compensate the operation within the rating.

Further, according to the invention described in claims 7 and 8,
Even when the AC power supply is normal, the uninterruptible power supply is also used to supply power to the fixing heater, so that the fixing roller can be quickly raised to a predetermined temperature under conditions where power distribution is restricted. The processing speed will not be delayed.

Similarly, according to the ninth and tenth aspects of the present invention, during image formation, even if the AC power supply is normal, the uninterruptible power supply is also used to supply power to the fixing heater under a predetermined condition. It is possible to prevent the temperature of the fixing roller from lowering under the condition that the power distribution is restricted, and it is possible to perform the image forming process without being restricted by slowing down the processing speed.

[Brief description of drawings]

FIG. 1 is a block diagram of a power supply section showing an embodiment of the invention described in claim 1.

FIG. 2 is a schematic configuration diagram of the entire digital copying machine.

FIG. 3 is a plan view showing a writing system configuration.

FIG. 4 is a front view thereof.

FIG. 5 is a schematic block diagram showing an entire electrical equipment control system.

FIG. 6 is a block diagram mainly showing the vicinity of a scanner control system.

FIG. 7 is a block diagram mainly showing a sorter and a double-sided control system.

FIG. 8 is a block diagram mainly showing a paper feed control system.

FIG. 9 is a block diagram mainly showing a sequence control system.

FIG. 10 is a block diagram mainly showing a main control system.

FIG. 11 is a block diagram showing a processing circuit in the scanner.

FIG. 12 is a block diagram showing an IPU configuration.

FIG. 13 is a schematic diagram showing an IPU output data format.

FIG. 14 is a block diagram showing a memory system.

FIG. 15 is a block diagram showing an example of its general configuration.

FIG. 16 is a block diagram showing a configuration example of the embodiment system.

FIG. 17 is a block diagram illustrating a memory device.

FIG. 18 is a block diagram showing a configuration example of the memory unit.

FIG. 19 is a schematic diagram showing a data configuration example.

FIG. 20 is a block diagram showing a modified example of the memory device.

FIG. 21 is a block diagram illustrating a configuration example of an external storage device.

FIG. 22 is a block diagram showing another modification of the memory device.

FIG. 23 is a circuit diagram showing an AC voltage drop detection circuit.

FIG. 24 is a timing chart showing an example of a signal waveform of each part of the AC power supply drop detection circuit.

FIG. 25 is a timing chart showing a process when power is cut off.

FIG. 26 is a characteristic diagram showing a temperature characteristic of a fixing unit when power is turned off.

FIG. 27 is a plan view showing a configuration example of an operation unit.

FIG. 28 is a timing chart showing a copy process involving a shutdown process.

FIG. 29 is a general flowchart showing copy control.

FIG. 30 is a general flow chart illustrating a shutdown process.

FIG. 31 is a block diagram of a power supply section showing an embodiment of the invention described in claim 2;

FIG. 32 is a block diagram of a power supply section showing an embodiment of the present invention according to claims 3 and 4.

FIG. 33 is a flowchart showing the processing.

FIG. 34 is a block diagram showing a modified example.

FIG. 35 is a flowchart showing the processing.

FIG. 36 is a schematic block diagram showing an embodiment of the invention described in claims 5 and 6.

FIG. 37 is a schematic block diagram showing a modified example.

FIG. 38 is a schematic block diagram showing another modified example.

FIG. 39 is a block diagram of a power supply section showing an embodiment of the inventions set forth in claims 7 and 9.

FIG. 40 is a block diagram of a power supply section showing an embodiment of the invention described in claims 8 and 10.

[Explanation of symbols]

 1, 2 and 3 units 61 power supply control means 90 AC power supply 91 uninterruptible power supply 200 AC voltage drop detection means 260 instantaneous interruption simulation means & control means 264 supply destination switching means 266 power supply switching means 268 power supply switch 269 power supply switch judging means 274 Current limiting unit 270-274 Consumption current detection unit 275-277 Supply source switching unit 294 Fixing heater 294a First fixing heater 294b Second fixing heater

Claims (10)

[Claims] 1. An image forming apparatus with an uninterruptible power supply, which has an uninterruptible power supply that supplies power for a predetermined time when the AC power supply is cut off, and an AC voltage drop detecting means for detecting a drop in the AC voltage of the AC power supply, and the AC. From the reset time detected by the instantaneous interruption simulation means when the AC voltage drop is detected by the AC voltage drop detection means, and the instantaneous disconnection simulation means for measuring the reset time of the image forming apparatus by instantaneously disconnecting the power supply. An image forming apparatus with an uninterruptible power supply, comprising: a control unit that controls the start of the evacuation process by the uninterruptible power supply after a lapse of a predetermined short time. 2. An image forming apparatus with an uninterruptible power supply, which has an uninterruptible power supply for supplying power for a predetermined time when the AC power supply is cut off, and an AC voltage drop detecting means for detecting a drop in the AC voltage of the AC power supply, and an AC voltage When the AC voltage drop occurs during the image formation, the uninterruptible power supply supplies power to all units of the image forming apparatus and the image formation occurs when the AC voltage drop occurs during the image formation. An image forming apparatus with an uninterruptible power supply, characterized in that supply destination switching means for supplying power from an uninterruptible power supply only to a DC power supply unit in the apparatus. 3. An image forming apparatus with an uninterruptible power supply, which has an uninterruptible power supply for supplying power for a predetermined time when the AC power supply is cut off, and AC voltage drop detecting means for detecting a drop in the AC voltage of the AC power supply, and an AC voltage. When the AC voltage drop occurs during the image formation, the time point of the AC voltage drop is determined, and when the AC voltage drop occurs during the image formation, the image forming apparatus is supplied with power from the uninterruptible power supply and the AC voltage drop occurs at the standby time. An image forming apparatus with an uninterruptible power supply, which is provided with a power supply switching means for turning off the power supply to the image forming apparatus at the time of. 4. A power switch determination means for detecting an open / closed state of a power switch with respect to an AC power source when power supply by the power supply switching means is turned off, and a current setting in the image forming apparatus when the power switch is determined to be closed. 4. The image forming apparatus with an uninterruptible power supply according to claim 3, further comprising a mode storing means for storing the mode. 5. An uninterruptible power supply having power supply means for individually supplying power to a plurality of units inside the image forming apparatus based on an AC power supply, and an uninterruptible power supply for supplying power for a predetermined time when the AC power supply is cut off. In the attached image forming apparatus,
Current limiting means for limiting an input current from the AC power source to the uninterruptible power supply, current consumption detecting means for detecting a current consumption flowing to each unit, and a unit for which the detected current consumption exceeds a certain value. An image forming apparatus with an uninterruptible power supply, comprising: a supply source switching means for switching power supply from the corresponding power supply means to the uninterruptible power supply. 6. The image forming apparatus with an uninterruptible power supply according to claim 5, wherein priority is given to the switching of the power supply source to the unit based on the current consumption in each unit. 7. An image forming apparatus with an uninterruptible power supply, which has an uninterruptible power supply for supplying power for a predetermined time when the AC power supply is cut off, is provided with a first fixing heater and a second fixing heater in a fixing roller, and when the power is turned on. Power supply control means for supplying electric power from the AC power supply to the first fixing heater and supplying electric power from the uninterruptible power supply to the second fixing heater until the fixing roller reaches a predetermined temperature. An image forming apparatus with an uninterruptible power supply, which is provided with. 8. An image forming apparatus with an uninterruptible power supply, which has an uninterruptible power supply for supplying power for a predetermined time when AC power is shut off, wherein the fixing roller is provided from the time of power-on until the temperature of the fixing roller rises to a predetermined temperature. An image forming apparatus with an uninterruptible power supply, comprising power supply control means for supplying electric power to both of the AC power supply and the uninterruptible power supply to a fixing heater therein. 9. An image forming apparatus with an uninterruptible power supply, which has an uninterruptible power supply for supplying power for a predetermined time when AC power is cut off, is provided with a first fixing heater and a second fixing heater in a fixing roller, and an image is being formed. Until a predetermined condition is satisfied, power is supplied from the AC power supply only to the first fixing heater, and when a predetermined condition is satisfied, power is supplied from the AC power supply to the first fixing heater. An image forming apparatus with an uninterruptible power supply, comprising power supply control means for supplying electric power to the fixing heater from the uninterruptible power supply. 10. An image forming apparatus with an uninterruptible power supply, which has an uninterruptible power supply for supplying power for a predetermined time when AC power is cut off, wherein the fixing heater in the fixing roller is used until a predetermined condition is satisfied during image formation. An uninterruptible power supply is provided which supplies power only from an AC power supply, and supplies power to the fixing heater from both the AC power supply and the uninterruptible power supply when a predetermined condition is satisfied. Image forming apparatus with power supply.