JP2004236492A - Power supply device and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply device which can cope with a rapid output variation without increasing the capacity of auxiliary power supply more than that required, and by which working electric power is leveled not to exceed the maximum electric power of an AC line that can be supplied. <P>SOLUTION: The power supply device includes power supply, a first power supply means that can not store power, a second power supply means that can store electric power, a switching means which switches whether power to a part of loads is supplied by the first power supply means or by the second power supply means, and a switching control means that controls the switching means. The control means predicts working electric power consumption, and controls the switching means so that power to a part of the loads is supplied from the second power supply means when the predicted electric power consumption exceeds the electric power of the first power supply means that can be supplied. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device and an image forming apparatus, and more particularly, to power averaging so that power consumption does not exceed power that can be supplied to a power supply line in an image forming apparatus such as a laser printer, a digital copying machine, and a multifunction peripheral. About technology.
[0002]
[Prior art]
2. Description of the Related Art In recent years, copiers, printers, facsimile machines, and multifunction machines that combine these using an electrophotographic process have become multifunctional, and accordingly, the structure has become complicated and the maximum power consumption tends to increase. On the other hand, there is a limit to the power that can be supplied from a normal power supply line, and this is a great restriction in designing equipment.
[0003]
Therefore, as one of the prior arts for leveling the load power, Patent Literature 1 described above provides a means for monitoring the power supplied from the main power supply, so that the power supplied from the main power is less than a predetermined value. Sometimes, the auxiliary power supply is charged, and when the supply power of the main power supply is larger than a predetermined value, the energy stored in the auxiliary power supply is discharged, thereby leveling the power that changes rapidly in a relatively short time. The technology is disclosed.
[0004]
[Patent Document 1]
JP-A-2002-199588
[0005]
[Problems to be solved by the invention]
However, according to Patent Literature 1, the power consumption is monitored, and when the power supplied from the main power supply exceeds a predetermined threshold, feedback control of supplying power from the auxiliary power supply is performed. If the change is more steep than expected, there is a problem that the power supply capacity of the main power supply is exceeded. Further, even if the auxiliary power supply is operated early by lowering the threshold value in order to prevent this, the capacity of the auxiliary power supply needs to be large because the time for using the auxiliary power supply is long, so that the cost is increased, and furthermore, the device is required. There is a problem that it becomes large.
[0006]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and it is possible to cope with a sudden output fluctuation without increasing the capacity of an auxiliary power supply more than necessary, and to level the power consumption by using an AC line. It is an object of the present invention to provide a power supply device and an image forming apparatus capable of not exceeding the maximum suppliable power.
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the invention according to claim 1 is a power supply device that supplies power for operating each load, wherein a first power supply unit for supplying power to each load; A second power supply means capable of storing, a switching means for switching a power supply source for some loads to the first power supply means and the second power supply means, Prediction means for predicting, and switching control means for controlling the switching means on the basis of the power consumption predicted by the prediction means, wherein the switching control means uses the power consumption predicted by the prediction means. When the power that can be supplied by the first power supply means is exceeded, the switching means is controlled such that power supply to the partial load is performed from the second power supply means.
[0008]
According to the above invention, the switching means switches the power supply source for some loads between the first power supply means and the second power supply means which is an auxiliary power supply, and the prediction means uses When the power consumption predicted by the prediction means exceeds the power that can be supplied by the first power supply means, the switching control means switches the power supply to some loads to the second power supply means. By controlling the switching means to start from the same, it is possible to respond to sudden output fluctuations without increasing the capacity of the auxiliary power supply more than necessary, and to equalize the power used and supply the maximum AC line Do not exceed power.
[0009]
The invention according to claim 2 is the invention according to claim 1, further comprising storage means for storing information on power consumption of each load, wherein the prediction means determines a load to be operated, and The power consumption is predicted based on power consumption information for each load stored in the means.
[0010]
According to the above invention, the prediction means determines the load to be operated, and predicts the power consumption based on the information on the power consumption for each load stored in the storage means. Predict power.
[0011]
According to a third aspect of the present invention, in the invention according to the second aspect, the storage unit stores information on power consumption for each operating state of each load, and the prediction unit is stored in the storage unit. The power consumption is predicted for each operation state based on the power consumption information for each operation state for each load.
[0012]
According to the above invention, the prediction unit predicts the power consumption for each operation state based on the power consumption information for each operation state for each load stored in the storage unit, so that the start time is determined. At all times, the power consumption information stored in the storage unit is switched to predict the power consumption, and more accurate power consumption prediction is performed in consideration of short-term fluctuations in power consumption.
[0013]
According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the part of the load exceeds a power that can be supplied by the first power supply means. It is an operating load.
[0014]
According to the above invention, when the predicted power consumption exceeds the power that can be supplied by the first power supply means, the load for supplying power from the second power supply means is changed to the load of the first power supply means. By using a load that operates when the power that can be supplied is exceeded, the power used is leveled by an auxiliary power supply having a small capacity so as not to exceed the maximum suppliable power of the AC line.
[0015]
According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, when the load exceeds a power that can be supplied by the first power supply means, It is a load that operates intermittently.
[0016]
According to the above invention, when the predicted power consumption exceeds the power that can be supplied by the first power supply means, the load for supplying power from the second power supply means is changed to the load of the first power supply means. By setting the load to operate intermittently when the power that can be supplied is exceeded, the second power supply means is charged little by little during the intermittent operation, thereby further reducing the capacity of the auxiliary power supply.
[0017]
According to a sixth aspect of the present invention, in the invention of the fifth aspect, there is provided a correction means for correcting the information on the power consumption of each load stored in the storage means.
[0018]
According to the above invention, the correction unit corrects the information on the power consumption of each load stored in the storage unit, thereby making a more accurate prediction of the power consumption in consideration of the fluctuation of the power consumption.
[0019]
The invention according to claim 7 is the invention according to claim 6, wherein the correction unit includes a measurement unit that measures a load current of the load, and the correction unit is configured to perform a measurement based on a measurement result of the measurement unit. The power consumption information of each load stored in the storage unit is corrected.
[0020]
According to the invention, the measuring unit measures the load current of the load, and the correcting unit corrects the information of the power consumption of each load stored in the storage unit based on the measurement result of the measuring unit. More accurate power consumption prediction is performed in consideration of long-term fluctuations in power consumption.
[0021]
The invention according to claim 8 is the invention according to any one of claims 1 to 7, wherein the second power supply means is an electric double layer capacitor.
[0022]
According to the above invention, the use of the electric double layer capacitor as the second power supply means makes it possible to prolong the service life of the auxiliary power supply and rapidly charge the auxiliary power supply.
[0023]
According to a ninth aspect of the present invention, there is provided a power supply device according to any one of the first to eighth aspects.
[0024]
According to the invention, by applying the power supply device according to any one of claims 1 to 8 to an image forming apparatus, power consumption does not exceed power that can be supplied to a power supply line in the image forming apparatus. To do.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of a power supply device and an image forming apparatus according to the present invention will be described in detail in the order of (Embodiment 1) and (Embodiment 2) with reference to the drawings.
[0026]
(Embodiment 1)
FIG. 1 is a perspective view showing the appearance of a digital copying machine which is an example of an image forming apparatus according to one embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a digital copying machine. The digital copying machine 1 includes a main body 10, a large-volume paper supply device (hereinafter abbreviated as LCT) 11, and a finisher 12 for performing sorting, punching, stapling, and the like. In addition, an automatic document feeder (hereinafter abbreviated as ADF) 13 for placing and reading a document on the upper portion of the main body 10 and a reading mode, setting of a copy magnification, setting of a paper feed stage, The finisher 12 includes an operation unit 14 for performing post-processing settings, displaying to an operator, and the like.
[0027]
Further, the lower side of the main body 10 and the LCT 11 have paper feed units 15 and 16, and the finisher 12 has a paper discharge unit 17. The inside of the digital copying machine 1 incorporates well-known mechanisms and control devices of the digital copying machine, such as an exposure optical system, a paper feeding and conveying system, a developing system, a fixing system, and a paper discharging system. Has been realized. That is, by placing the original on the installation surface of the ADF 13 and pressing the copy start key on the operation unit 14, the original is supplied onto a contact glass (not shown) below the ADF 13, and the original is illuminated by an illumination system (not shown). Read by the imaging optical system. Then, after performing various corrections and processing on the read image data, the writing system irradiates a beam with a laser diode based on the image data to form an electrostatic latent image on a photosensitive member (not shown). Thereafter, through a so-called electrophotographic process, a copy image is formed on a sheet fed from the sheet feeding unit 15 or 16 instructed by the operation unit 14, and post-processing such as sorting, punching, and stapling is performed by the finisher 12. Then, the paper is discharged to the paper discharge unit 17.
[0028]
The digital copying machine 1 also has a printer function, and can receive image data from a host computer (not shown) via a network (not shown) and perform image formation similarly. Further, the digital copying machine 1 has a scanner function, and can transmit read and digitized image data to a host computer (not shown) via a network (not shown). In addition, these functions can perform parallel / reserved operations, read the original for the next copy operation during the copy operation, expand the print data during the copy operation, and perform the print operation after the copy is completed. Also, it is configured such that a document can be read using a scanner function during a printing operation.
[0029]
FIG. 2 is a diagram showing an example of a power supply device of the digital copying machine of FIG. The power supply device shown in FIG. 1 includes an AC line 21 for supplying AC power, an AC / DC converter 22 for generating +38, +24 V, and +5 V DC power based on the AC power, and an electric double layer capacitor 24. Circuit 23, an electric double-layer capacitor 24 as an auxiliary power supply, a step-up / down converter 25 for adjusting the output voltage level of the electric double-layer capacitor 24, and an AC / DC power supply source to the + 24V system load 28b. A switching circuit 26 for switching between the converter 22 and the electric double layer capacitor 24, a + 24V system load 28a, 28b, a +38 system load 28c, a + 5V system load 28d, and a control unit 30 for controlling operations of the digital copying machine and the power supply device. And
[0030]
2, an AC power supplied from an AC line 21 is converted into a DC power by an AC / DC converter 22, and a part of the power is directly supplied as power to the + 38V, + 24V, and + 5V system loads 28c, 28a, 28b, and 28d. I do. Further, + 38V can be used for charging the electric double layer capacitor 24 as an auxiliary power supply via the charging circuit 23.
[0031]
As the auxiliary power source, other than the electric double layer capacitor can be used. In this embodiment, an electric double layer capacitor which can be charged and discharged in a short time and has a long life is used. Since the terminal voltage of the electric double-layer capacitor 24 decreases as the electric double-layer capacitor 24 discharges, the step-up / step-down converter 25 is arranged at the subsequent stage of the electric double-layer capacitor 24 so that the output voltage becomes constant. In the present embodiment, since the voltage is supplied to the + 24V system load 28b, the step-up / step-down converter 25 is configured to be able to output + 24V when the input voltage is in the range of + 38V to + 10V.
[0032]
The switching circuit 26 accumulates the +24 V power generated by the AC / DC converter 22 based on the AC power supplied from the AC line 21 and the electric double layer capacitor 24 according to the control signal input from the control unit 30. The energy is switched to a + 24V power supply generated through the buck-boost converter 25 from the energy and supplied to the + 24V system load 28b.
[0033]
The control unit 30 controls the entire digital copying machine 1, and operates the loads 28a to 28d sequentially according to each operation mode. The control unit 30 also controls charging / discharging of the electric double layer capacitor 24. As described later, the control unit 30 uses the power supplied from the AC line 21 to supply power to all loads according to the predicted power consumption. If it is determined that the supply is possible, the switching circuit 26 is switched so as to supply the +24 V power generated by the AC / DC converter 22 to the +24 V system load 28b, and the charging circuit 23 is controlled for a margin. To charge the electric double layer capacitor 24. On the other hand, when the control unit 30 determines that the power supplied from the AC line 21 is not enough to supply power to all loads, the control unit 30 converts the energy stored in the electric double-layer capacitor 24 into the buck-boost converter 25. The switching circuit 26 is switched so as to supply the + 24V power generated through the power supply to the + 24V system load 28b.
[0034]
FIG. 3 is a block diagram illustrating a configuration of the control unit 30 of FIG. 2 and a peripheral device related to control of image data by the control unit 30. In the figure, a control unit 30 includes a CPU 31 for controlling a digital copying machine and a power supply device in accordance with a program and data stored in a ROM 32 and a program and data stored in a nonvolatile RAM 34, and a program for operating the CPU 31. ROM 32 to be stored, RAM 33 used as a work memory of CPU 31, adjustment values such as control and timing, and power consumption data for each operation state (data of power consumption at peak (startup), A non-volatile RAM 34 for storing a power consumption table storing average power consumption data (at a steady state), and an I / O for controlling the loads 28a to 28d based on the input of each sensor 47 of the digital copying machine 1. An O control unit 35 is provided.
[0035]
The power consumption table stored in the non-volatile memory 34 stores information on power consumption for each load as to how much power is consumed at peak and average when each load is operated. The power consumption table contains power consumption data for each operation state for each load at startup, copy mode operation, scanner mode operation, printer mode operation, energy saving mode, low power consumption mode. Data of power consumption in various operation states such as time may be stored.
[0036]
On the other hand, as for the image data, when the original is supplied onto the contact glass by the ADF 13 in FIG. 1, the image data is read by the reading unit 45. The read image data is subjected to MTF correction, scaling processing, image quality correction, and the like by the image processing unit 42 in accordance with the mode set in the operation unit 14 in FIG. 1, and then the image RAM 43 and the HDD 44 are controlled. And stored in the HDD 44 via the HDD controller 41.
[0037]
Here, the reason why images are stored in both the image RAM 43 and the HDD 44 is that the image RAM 43 has a capacity of only about five A4 documents, but since the number of documents is not known at the start of copying, a plurality of copies are sorted. If the number of originals exceeds five when making a copy, the sort operation is realized by copying the image data from the HDD 44 to the image RAM 43 and performing the copy operation when performing the copy operation for the second copy and thereafter. It is also used for a recovery operation when a paper jam occurs. Then, writing is performed by the writing section 46 in accordance with the timing of the sheet fed from the sheet feeding section 15 or 16. Since these components are well-known techniques and are not special features in the present invention, detailed description thereof will be omitted.
[0038]
Next, prediction of power consumption by the control unit 30 in FIG. 3 will be described. As described above, the power consumption table of the nonvolatile RAM 34 stores information on how much power is consumed in peak and average when operated for each load. Since the operation of each of the loads 28a to 28d is controlled in accordance with the operation mode according to the program stored in the power supply circuit, the operation is performed at a short time after switching the power supply by controlling the switching circuit 26 in FIG. It is possible to predict the load that is occurring.
[0039]
Therefore, the control unit 30 predicts the operation of the load at a predetermined cycle, and refers to the power consumption table to estimate the power consumption of the device by adding the power consumption of each load predicted to be operating. I do. For a load such as a motor, a large current flows at the time of startup and power consumption increases. Therefore, several periods at the beginning of operation are calculated using peak power, and thereafter, the average power is used to calculate the accuracy of power consumption prediction accuracy. Can be improved.
[0040]
Next, control of charging and discharging of the electric double layer capacitor 34 as an auxiliary power supply by the control unit 30 of FIG. 3 will be described with reference to FIG. FIG. 4 shows an operation flow of control of charging and discharging of the electric double layer capacitor 34 as an auxiliary power supply by the control unit 30 of FIG.
[0041]
First, the power consumption after a predetermined time is predicted by the above-described method (step S101). Then, it is determined whether the predicted power consumption can be supplied only by the AC power supplied from the AC line 21 in FIG. 2 (step S102). If the power supply is broken ("YES" in step S102), the power available for charging is calculated (step S103), and the power supply to the + 24V load 28b in FIG. 2 is performed by the switching circuit 26 in FIG. As the + 24V power generated by the AC / DC converter 22 in FIG. 2 based on the AC power supplied from the AC line 21, the charging circuit 23 in FIG. The electric double layer capacitor 24 is charged (step S104).
[0042]
On the other hand, when it is determined that the power consumption predicted in step S101 cannot be supplied only by the AC power supplied from the AC line 21 (“NO” in step S102), the charging of the electric double layer capacitor 24 by the charging circuit 23 is performed. And the switching circuit 26 switches the power supply to the +24 V system load 28b from the energy stored in the electric double layer capacitor 24 to the +24 V power generated through the step-up / step-down converter 25 in FIG. 2 (step S105).
[0043]
Next, the actual operation of the digital copying machine will be described with reference to FIGS. FIG. 5 is a characteristic diagram showing changes in power consumption in various operations of the digital copying machine, and FIG. 6 is a characteristic diagram showing changes in power consumption in the copy mode.
[0044]
FIG. 5A shows how the power consumption changes when the copy mode is executed. In the period (1), the heater is turned on according to the temperature in order to maintain the temperature of the fixing unit. The power consumption is not constant because / OFF is repeated. The period of (2) is a period in which a document is set on the ADF 13 in FIG. 1 and a copy operation is started, a document is read, and a printing operation is performed. The period of (3) is a period in which the reading of the original is completed and only the printing operation is performed, and the period of (4) is a state in which the printing operation is completed and the operation returns to the standby state again.
[0045]
FIG. 5B shows how the power consumption changes in the print mode, and FIG. 5C shows how the power consumption changes in the scanner mode.
[0046]
Even in the copy mode, the load and operation timing vary depending on the tray from which the paper is fed, whether it is two-sided copy or one-sided copy, and whether or not there is post-processing such as punching, sorting, and stapling. Power consumption and power fluctuation patterns change. As a result, as indicated by the hatched portions in FIG. 6, the maximum power that can be supplied from the AC line 21 in FIG. However, the period during which the power consumption increases and exceeds the maximum power that can be supplied from the AC line 21 is usually a short period, and in the present invention, the timing at which this period occurs is predicted in advance, By switching the power supply of some of the loads 28b to the auxiliary power, the maximum power that can be supplied to the AC line 21 is not exceeded.
[0047]
In addition, since switching is performed in anticipation, it is not feedback-type control that switches between the main power supply and the auxiliary power supply by detecting power consumption. Therefore, there is no need to consider delays. There is no need to have a margin as described above, and the time for using the auxiliary power supply can be shortened. For this reason, the capacity of the auxiliary power supply can be reduced.
[0048]
At this time, the +24 V load 28b supplied from the electric double layer capacitor 24 serving as the auxiliary power supply operates when the maximum power that can be supplied from the AC line 21 is exceeded (needs to be operated), in particular, , A load for performing an intermittent operation (for example, a fixing device or the like). With this configuration, the capacity of the auxiliary power supply can be further reduced by charging the battery in small increments between intermittent operations by taking advantage of the characteristics of the electric double layer capacitor that can be rapidly charged and discharged. Then, the load can be leveled so as not to exceed the maximum power that can be supplied from the AC line 21 with a small capacity auxiliary power supply.
[0049]
As described above, according to the power supply device of the first embodiment, the AC / DC converter 22 that generates +38 V, +24 V, and +5 V system voltages based on the AC power supplied from the AC line 21, and the auxiliary power supply And a switching circuit 30 for switching the source of power supply to the + 24V system load 28b to the AC / DC converter 22 or the electric double layer capacitor 24. The power consumption of each load (+24 V load 28 a, 28 b, +38 V load 28 c, +5 V load 28 d) stored in the performance RAM 34 is used to predict the power consumption of the load to be operated, and the predicted usage When the power consumption exceeds the power that can be supplied by the AC / DC converter 22, the power supply to the + 24V load 28b is performed by the electric double layer converter. Since the switching circuit 30 is controlled so as to perform the operation from the sensor 24, it is possible to cope with a sudden output fluctuation without increasing the capacity of the auxiliary power supply more than necessary, and to level the power consumption by using the AC power. It is possible not to exceed the maximum suppliable power of the line.
[0050]
(Embodiment 2)
A digital copying machine according to a second embodiment will be described with reference to FIGS. The digital copier according to the first embodiment has fixed power consumption information in a power consumption table for estimating power consumption, whereas the digital copier according to the second embodiment has a power consumption table. By correcting the power consumption information over time, it is possible to accurately predict the power consumption even when the power consumption of the load changes due to aging or the like. The digital copying machine according to the second embodiment has substantially the same configuration as the digital copying machine according to the first embodiment, and therefore, only different portions will be described here.
[0051]
FIG. 7 is a diagram illustrating an example of a power supply device of the digital copying machine according to the second embodiment, and FIG. 8 is a block diagram illustrating a control unit 30 of FIG. 7 and a configuration of a peripheral device related to control of image data by the control unit 30. FIG. 7 and 8, parts having the same functions as those in FIGS. 2 and 3 are denoted by the same reference numerals, and description of common parts is omitted.
[0052]
The power supply device shown in FIG. 7 is different from the power supply device of FIG. 2 in that load current measuring circuits 50a to 50c for measuring the load current of each load are provided on the + 38V and + 24V power supply lines. The load current measuring circuits 50a to 50c output analog output voltages according to the input load current. The control unit 30 shown in FIG. 8 is different from the control unit 30 shown in FIG. 3 in that an A / D converter 51 for digitally converting analog output voltages output from the load current measurement circuits 50a to 50c is provided. .
[0053]
With reference to FIGS. 7 and 8, correction of information on power consumption stored in the power consumption table by control unit 30 will be described. Since the power consumption of each of the loads 28a to 28d changes according to the state of each of the loads 28a to 28d, the power consumption increases and decreases over time and over time as the load increases and decreases due to wear and the like. To correct this, as shown in FIG. 7, load current measuring circuits 48a to 48c are provided on the + 38V and + 24V power supply lines, and the control unit 30 converts the analog output voltage into digital data by the A / D converter 51. The power consumption information in the power consumption table of the nonvolatile RAM 24 is rewritten based on the converted digital data. Then, the control unit 30 uses the rewritten power consumption information in the power consumption table for estimating the power consumption. This makes it possible to improve the accuracy of predicting the power consumption in consideration of long-term fluctuations in power consumption.
[0054]
As the load current measuring circuits 50a to 50c, for example, current-voltage conversion resistors inserted in series into + 38V and + 24V lines can be used. For example, assuming that the resistance value of the current-voltage conversion resistor is 0.5Ω, the load initially flows at about 1 A at a certain load, but after a certain period, the load changes and the current flows at 1.1 A. I do. At this time, the voltage between both ends of the current-voltage conversion resistor changes from 0.5 V to 0.55 V. Therefore, the A / D converter 51 sets 12 bits between 0 and 5 V (0 value to 4095 value). When A / D conversion is performed, digital data changes from 409 values to 450 values. Since the load current and the power consumption at the load have linearity, the power consumption is calculated based on this digital data and the value is stored in the power consumption table to correct long-term changes in power consumption. It is possible to do.
[0055]
The control of charging / discharging of the electric double layer capacitor 34 and the operation of the digital copying machine are the same as those in the first embodiment (FIGS. 4 to 6), and thus the description thereof is omitted.
[0056]
As described above, according to the second embodiment, the load current measuring circuits 48a to 48c are provided on the + 38V and + 24V power supply lines, and the control unit 30 uses the A / D converter 51 to convert the analog output voltage into digital data. Since the power consumption information in the power consumption table of the nonvolatile RAM 24 is corrected based on the converted digital data, it is possible to more accurately predict the power consumption in use in consideration of the fluctuation of the power consumption. It becomes possible.
[0057]
The present invention is not limited to the above-described embodiment, and can be appropriately modified without changing the gist of the invention.
[0058]
【The invention's effect】
As described above, according to the power supply device according to claim 1, in the power supply device that supplies power for operating each load, the first power supply unit for supplying power to each load, Power supply means capable of storing power, switching means for switching a power supply source for some loads to the first power supply means and the second power supply means, and power consumption. Prediction means, and switching control means for controlling the switching means based on the power consumption predicted by the prediction means, wherein the switching control means uses the power consumption predicted by the prediction means. When the power exceeds the power that can be supplied by the first power supply unit, the switching unit is controlled so that power supply to the partial load is performed from the second power supply unit. Auxiliary power capacity is required. Without increasing the capacity to above, the sudden output change can correspond, and the power used can not exceed the maximum available power of the AC line and leveling.
[0059]
According to the power supply device of the second aspect, the power supply device of the first aspect further includes a storage unit that stores information on power consumption for each load, and the prediction unit determines a load to be operated. Since the power consumption is predicted based on the power consumption information for each load stored in the storage unit, the power consumption can be predicted by a simple method.
[0060]
According to the power supply device of the third aspect, in the power supply device of the second aspect, the storage unit stores information on power consumption for each operation state of each load, and the prediction unit stores the power consumption information. Based on the power consumption information for each operation state for each load stored in the means, the power consumption is predicted for each operation state. It is possible to predict the used power consumption by switching the information of the consumed power, and to more accurately predict the used power consumption in consideration of the short-term fluctuation of the power consumption.
[0061]
Further, according to the power supply device according to claim 4, in the power supply device according to any one of claims 1 to 3, the part of the load is a power that can be supplied by the first power supply unit. Since the load operates when the power exceeds the maximum, it is possible to equalize the power used by the auxiliary power supply having a small capacity so as not to exceed the maximum suppliable power of the AC line.
[0062]
Further, according to the power supply device according to claim 5, in the power supply device according to any one of claims 1 to 4, the part of the load is a power that can be supplied by the first power supply unit. Is exceeded, the load is determined to be an intermittent operation, so that the second power supply means can be charged little by little during the intermittent operation, and the capacity of the auxiliary power supply can be further reduced.
[0063]
According to the power supply device of the sixth aspect, the power supply device of the fifth aspect further includes a correction unit that corrects information on power consumption of each load stored in the storage unit. It is possible to more accurately predict the power consumption in use in consideration of the fluctuation of the power consumption.
[0064]
According to the power supply device according to claim 7, in the power supply device according to claim 6, the correction unit includes a measurement unit that measures a load current of a load, and the correction unit determines a measurement result of the measurement unit. , The power consumption information of each load stored in the storage means is corrected, so that more accurate power consumption prediction can be performed in consideration of long-term fluctuations in power consumption. .
[0065]
Further, according to the power supply device of claim 8, in the invention according to any one of claims 1 to 7, the second power supply means is an electric double layer capacitor. The service life of the auxiliary power supply can be prolonged and quick charging can be performed.
[0066]
Further, according to the image forming apparatus of the ninth aspect, since the power supply device according to any one of the first to eighth aspects is provided, power that can be supplied from the power supply line in the image forming apparatus is consumed. It is possible not to exceed the power.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an external appearance of a digital copying machine as an example of an image forming apparatus according to a first embodiment.
FIG. 2 is a block diagram showing a configuration of the power supply device of FIG.
3 is a block diagram illustrating a configuration of a control unit of FIG. 2 and peripheral devices related to control of image data by the control unit.
FIG. 4 is a flowchart showing a control operation of charging / discharging an auxiliary power supply by a control unit.
FIG. 5 is a characteristic diagram showing a change in power consumption in various operations.
FIG. 6 is a characteristic diagram showing a change in power consumption in a copy mode according to the present invention.
FIG. 7 is a block diagram illustrating a configuration of a power supply device according to a second embodiment;
8 is a block diagram illustrating a configuration of a control unit of FIG. 7 and a peripheral device related to control of image data by the control unit.
[Explanation of symbols]
1 Digital copier
10 body
11 LCT
12 Finisher
13 ADF
14 Operation unit
15, 16 Paper feed unit
17 paper output unit,
21 AC line
22 AC / DC Converter
23 charging circuit
24 Electric Double Layer Capacitor
25 Step-up / step-down converter
26 switching circuit,
28a-d load
30 control unit
50a-c load current measurement circuit
51 A / D converter

Claims (9)

In a power supply device that supplies power for operating each load,
First power supply means for supplying power to each load;
Second power supply means capable of storing power,
Switching means for switching a power supply source for some loads to the first power supply means and the second power supply means;
Prediction means for predicting power consumption,
A switching control unit that controls the switching unit based on the power consumption predicted by the prediction unit;
With
The switching control unit, when the power consumption predicted by the prediction unit exceeds the power that can be supplied by the first power supply unit, switches the power supply to the partial load to the second power supply unit. A power supply device for controlling the switching means so as to perform the switching from the start. Further, a storage unit that stores information on power consumption for each load is provided,
The power supply device according to claim 1, wherein the prediction unit determines a load to be operated, and predicts the power consumption based on power consumption information for each load stored in the storage unit. The storage unit stores information on power consumption for each operation state for each load,
The apparatus according to claim 2, wherein the prediction unit predicts the power consumption for each operation state based on information on power consumption for each operation state for each load stored in the storage unit. Power supply. The power supply device according to any one of claims 1 to 3, wherein the partial load is a load that operates when the power exceeds the power that can be supplied by the first power supply unit. . The power supply according to any one of claims 1 to 4, wherein the part of the load is a load that operates intermittently when the power that can be supplied by the first power supply unit is exceeded. apparatus. The power supply device according to claim 5, further comprising a correction unit configured to correct the information on the power consumption of each load stored in the storage unit. The correcting means includes a measuring means for measuring a load current of the load,
The power supply device according to claim 6, wherein the correction unit corrects the information on the power consumption of each load stored in the storage unit based on a measurement result of the measurement unit. The power supply device according to any one of claims 1 to 7, wherein the second power supply unit is an electric double layer capacitor. An image forming apparatus comprising the power supply device according to claim 1.

Images