JP2015215523A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of an image forming apparatus according to electrophotography that the image forming apparatus cannot react to a sudden requirement for suppression of power consumption because the image forming apparatus cannot either stop or resume printing halfway through the printing, or cannot reduce power consumption at real time.SOLUTION: An image forming apparatus includes communication control means for receiving a power consumption restriction requirement from a power supply control system, and power supply management means for controlling each means according to the consumable power. When the reduction of power consumption is necessary, printing is stopped by immediately stopping the power supply to a fixation heater even halfway through the printing. When the power supply to the fixation heater is immediately stopped halfway through the printing, the defectiveness of a corresponding page caused by the reduction of fixation temperature is determined. When the defectiveness is recognized, the corresponding page is discarded. When the reduction of power consumption is no longer necessary, print output is resumed from a page following a normally printed last page. In addition, the speed of printing is changed on the basis of a unit page according to the consumable power.

Description

  The present invention relates to a power consumption control method in an image forming apparatus such as a copying machine, a printer, a facsimile machine, and a multifunction machine, and a configuration and control method of a power supply system that realizes the method.

  Conventionally, electric devices used in offices and homes consume power at an arbitrary timing from an AC power line. In addition, an allowable current is set in the switchboard that supplies AC power, and when the power consumption exceeds the allowable value, the power supply is cut off by the breaker. For this reason, depending on the operation status of each electric device, a situation may occur in which the power supply is suddenly interrupted by the breaker.

  In order to solve such a problem, whether or not the power control unit permits power consumption of each electric device by transmitting and receiving power consumption information between the electric device connected to the AC power line and the power control unit Methods have been proposed for controlling. The power control unit transmits a control signal according to the setting of each electric device, determines whether each electric device can operate below the allowable power, and sets power distribution.

  For example, in a power supply system composed of a power supply unit and a power consumption unit (electrical equipment), the power supply unit and the power consumption unit communicate with each other using an identifier assigned so that each unit can be identified. Exchange power information with each other. And when the total power consumption of a power consumption unit exceeds the allowable value of the total supply power set to the power supply unit, the method of putting a power consumption unit into a low power consumption state is proposed (patent document 1). reference).

  As an example of the standard of the power management system, a control application profile in a home area called Smart Energy Profile by ZigBee (registered trademark) Alliance has been proposed. Smart Energy Profile functions include Demand Response, Load Control, Metering, Pricing, etc. When power demand is high, Demand Response can suppress the use of low-priority devices and adjust the temperature setting of the air conditioner. The company is trying to stabilize power supply and realize Home Energy Management.

JP 2007-189878

  However, it is difficult for a multi-function peripheral such as a page printer using electrophotographic technology to suddenly stop during printing or reduce power consumption in real time. In particular, the process of charging, latent image, development, transfer, and fixing cannot be interrupted in the middle of a page, so that there is a problem that it is impossible to respond to a sudden power consumption reduction request.

  In order to solve the above problems, a power consumption control method of the present invention is a power consumption control method in a power supply control system including an image forming apparatus including a power consumption control unit and a power supply control system having a power supply function. The method includes the steps of communicating between the image forming apparatus and the power supply control system to exchange power information with each other, and controlling the power consumption of the image forming apparatus. The image forming apparatus may be in a low power consumption state in accordance with power information from the power supply control system.

  In addition, the image forming apparatus is characterized by receiving a power consumption reduction request or power consumption information from the power supply control system, changing the print speed in units of pages, or interrupting and resuming printing in progress. To do.

  The image forming apparatus includes a communication control unit that receives a power consumption restriction request from the power supply control system, and includes a power supply management unit that controls a supply destination to which power is supplied according to consumable power, and executes printing. One of the features is that the print speed is changed according to the power that can be consumed.

  Further, when it is necessary to reduce the power that can be consumed, one of the features is that the power supply to the fixing heater is immediately stopped and the printing is interrupted even during the page being printed.

  One of the features is that when the power supply to the fixing heater is stopped immediately in the middle of the page being printed, it is determined whether the corresponding page is good or bad due to a decrease in fixing temperature, and if the page is defective, the corresponding page is discarded. . One feature is that when it is no longer necessary to reduce the power that can be consumed, the print output is resumed from the next page after the last page that has been successfully printed.

  According to the present invention, it becomes possible for a multi-function peripheral such as a page printer using electrophotographic technology to reduce the printing speed during printing or to interrupt and resume printing, thereby reducing power consumption. Is possible. And it becomes possible to reduce power consumption according to the sudden power consumption control request | requirement by Smart Energy Profile etc. by it.

1 is a block diagram illustrating an electrical configuration of an image forming apparatus according to the present invention. FIG. 3 is a configuration diagram of main units of a printing process of the image forming apparatus of the present invention. FIG. 4 is a diagram illustrating steps of a printing process of the image forming apparatus of the present invention. FIG. 5 is a diagram for explaining the operation of the image forming apparatus of the present invention. 6 is a flowchart for explaining the operation of the image forming apparatus of the present invention. 6 is a flowchart for explaining the operation of the image forming apparatus of the present invention. The figure which shows the connection form with the electric equipment in the electric power supply system of this invention.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram showing an electrical configuration of an image processing apparatus 100 according to an embodiment of the present invention. In FIG. 1, a control unit 101 controls the overall operation of the image processing apparatus 100. The ROM 102 stores programs executed by the control unit 101, various data, and the like. A program executed by the control unit 101 is expanded in the RAM 103 under the control of the control unit 101. Further, the RAM 103 is also used as a work area of the control means 101, a first image memory area used for the copying function, and a second image memory area used for the facsimile function.

  The timer means 116 counts an arbitrary time with a counter and outputs a trigger to the CPU 101. The clock circuit 112 is for outputting time information, and is driven by the primary battery 114. The operation unit 105 includes various keys for the user to operate the image processing apparatus, and the display unit 104 displays various information for operating the image processing apparatus. The FAX communication means 106 performs FAX communication via an analog telephone line. Further, the FAX communication means 106 has a memory receiving function for temporarily storing the received image in the RAM 103 without directly recording it on the recording paper and recording it on the recording paper.

  Further, the FAX communication means 106 has a timer transmission function for transmitting a transmission image at a set time after temporarily storing it in the RAM 103 without transmitting the transmission image immediately. Further, even when the main body power is turned off, the secondary battery 113 holds the FAX image memory area stored in the RAM 103 for a certain period of time. The image reading unit 108 is a document reading unit that reads a document. The image processing unit 109 performs conversion processing of the read image and image data to be recorded and output.

  The image forming unit 110 is an image forming unit that records and outputs image data on recording paper. In the case of a copying operation, the image forming unit 110 records and outputs the image data read by the image reading unit 108, and in the case of a printing operation, an image transferred from a PC. Data is recorded and output. The configuration and steps of the main unit of the print process, which is a component of the image forming unit 110, will be described with reference to FIG. The network communication unit 107 is a network communication unit that receives image data from a PC for printing and transfers image data read by the image reading unit 108 to the PC.

  The network communication means is also used for a remote user interface function for operating the apparatus by making an HTTP connection with a browser from a PC. The encoding / decoding unit 111 encodes the image data read by the image reading unit 108 by a predetermined method in advance when transmitting the image data by the FAX communication unit, or pre-prints the image data received by the FAX communication unit. It has a function of decoding by a predetermined method. Further, the encoding / decoding unit 111 has a function of encoding for temporarily storing image information of a plurality of pages when performing a copying operation, and decoding when outputting a print.

  The CPU bus 120 includes a control unit 101, a ROM 102, a RAM 103, an operation unit 105, a display unit 104, a FAX communication unit 106, a network communication unit 107, an image reading unit 108, an image processing unit 109, an image forming unit 110, and an encoding complex. CPU 111 for connecting means 111. The CPU bus 120 is a general term for an address bus for transferring address signals, a control bus for transferring control signals, and a data bus for transferring various data. The USB communication unit 115 is a USB communication unit that receives image data from the PC 1011 for printing and transfers image data read by the image reading unit 108 to the PC 1011.

  The power supply unit 130 supplies the power supplied from the commercial AC power supply line 1120 to each unit in the apparatus. The power supply circuit unit 1301 converts the power supply voltage required by each unit in the apparatus and supplies DC power to the electronic circuit unit or supplies high voltage power to the high voltage circuit unit and the heater unit.

  The communication control unit 1302 transmits / receives power information to / from the power supply control system (HEMS) 1400 and transmits the power information to the power supply management unit 1303. The communication data on the commercial AC power line 1120 is relayed between the control means 101 and the power supply control system (HEMS) 1400 when performing communication between the units. Input / output of signals to / from the power supply line 1120 is performed. The communication data from the control unit 101 is modulated and output to the commercial AC power line 1120 by the communication control unit 1302, and conversely, the signal from the commercial AC power line 1120 is demodulated and taken into the control unit 101 as communication data. Process so that you can.

  The power supply management unit 1303 transmits information to the control unit 101 according to consumable power information obtained from the communication control unit 1302, and controls the power supply to be supplied according to the operation of the apparatus.

  A power supply control system (HEMS) 1400 is provided in a switchboard that supplies power supplied from a commercial AC power supply line 1120 to each electrical device. It has demand response and load control support functions, control of each electric device that consumes power, setting of operation level such as temperature setting and emergency signal, transmission and reception of information such as operation setting, etc., in addition, metering support, It also has functions such as charge support.

  FIG. 2A is a configuration diagram of main units of a print process, which is a component of the image forming unit 110 of the image forming apparatus of the present invention. The laser beam from the laser unit 208 is scanned on the photosensitive drum by the scanning mirror 209 (this is called exposure). At this time, since the photosensitive drum 202 is already uniformly charged by the primary charging roller 201, an electrostatic latent image is formed on the photosensitive drum 202 by exposure. This electrostatic latent image becomes a visible image by the developing device 203 and is transferred onto paper by the next transfer charging roller 204. The paper to which the visible image is transferred is separated from the photosensitive drum 202 and sent to the fixing device 206 to fix the image.

  On the other hand, the photosensitive drum 202 after image transfer is cleaned by the drum cleaning unit 207 to prepare for the next print. The photosensitive drum 202 is the most important element in the electrophotographic process, and a semiconductor that changes its electrical characteristics by light irradiation is applied around an aluminum cylinder to form a drum shape. At present, OPC (Organic Photo Conductor) is used as a photoconductor for most LBPs, and A-Si (amorphous silicon) photoconductor drums are used for some large LBPs. The photosensitive layer generates positive and negative charges when exposed to light, and transports one charge to the drum surface to erase the charge on the drum surface. The polarity of charging is reversed between OPC and A-Si. Such a process of printing using the characteristics of the photosensitive drum is called an electrophotographic process.

  FIG. 2B is a diagram for explaining the steps of the printing process, which is a component of the image forming unit 110 of the image forming apparatus of the present invention.

S21 is a primary charging step:
A negative charge is placed on the surface of the photosensitive drum 202 from the primary charging roller 201 to uniformly charge the drum surface. When a DC voltage (DC bias) and an AC (AC bias) voltage are applied to the primary charging roller, the electric charge moves toward the photosensitive drum due to a potential difference between the roller and the photosensitive drum, and the photosensitive drum is charged. In addition to the DC bias, an AC bias is superimposed on the primary charging roller in order to keep the surface potential charged on the surface of the photosensitive drum uniform.

S22 is an exposure step:
The exposure neutralizes the charge on the photosensitive drum 202 to form an electrostatic latent image. A region irradiated with laser light is called a bright portion, and a region not irradiated with light is called a dark portion. In the bright portion, positive and negative charges are generated by exposure to neutralize the bright portion. This causes a difference in surface potential between the dark part and the bright part. The dark part potential at this time is called VD (dark part potential), and the bright part potential is called VL (bright part potential).

S23 is a development step:
The electrostatic latent image formed on the photosensitive drum 202 by the exposure step becomes a visible image by the developer (toner) at this step.

S24 is a transfer step:
In this step, the toner on the photosensitive drum 202 is transferred to paper. Here, transfer on the OPC photosensitive drum will be described. When positive charging is performed from the back side of the print paper, the positive charge reaches the surface of the print paper. At this time, if the potential of the print paper is higher than the potential of the place where the toner is attached (bright portion potential), the toner is negatively charged and is attracted to the print paper for transfer.

S25 is a separation step:
In this step, the print paper to which the toner has been transferred is separated from the photosensitive drum 202.

S26 is a fixing step:
The toner transferred to the printing paper is subjected to heat and pressure by the fixing device 206 in this step, so that the toner is fixed on the paper.

S27 is a drum cleaning step:
In the transfer step, most of the toner on the photosensitive drum 202 is transferred to the paper, but a small amount of toner may remain on the photosensitive drum without being transferred. In this step, the remaining toner is collected by the drum cleaning unit 207, and the surface of the photosensitive drum is physically cleaned.

  As described in S21 to S27, the page printer based on the electrophotographic technology cannot change the speed in the middle of the page, and cannot interrupt or resume printing.

  FIG. 3 is a diagram for explaining the print interruption operation and resumption operation of the image forming apparatus of the present invention.

  Next, the operation of the apparatus according to the present invention will be described with reference to the operation explanatory diagram of FIG. 3 and the block diagram of FIG. FIG. 3 shows an example in which the power supply to the fixing heater is stopped immediately upon receiving a power reduction request in the middle of the second page when printing five pages in one print job. The second page is fixed by residual heat, printed, and interrupted. After the third page, printing is suspended until the power that can be consumed is restored. If the print output for the second page is valid, printing is resumed from the third page after the power is restored. If the print output of the second page is invalid, after power is restored, printing is resumed from the second page.

  FIG. 4 is a flowchart showing an operation when there is no power reduction request during printing in the printing operation of the image forming apparatus according to the present embodiment. Note that the operations shown in the flowcharts of FIGS. 4 and 5 are realized by the control unit 101 executing each main program developed in the RAM 103. Further, some of the steps shown in the flowchart are realized by the communication control unit 1302 and the power supply management unit 1303 executing under the control of the control unit 101. Also, some of the steps shown in the flowchart are realized by the communication control unit 1302 and the power supply management unit 1303 independently executing regardless of the control unit 101.

  First, in step S <b> 401, the image forming apparatus receives a print job from the PC 1011 via the network communication unit 107 or the USB communication unit 115. In step S <b> 402, the power that can be consumed by the image forming apparatus is confirmed with the power supply control system 1400 via the communication control unit 1302. The power supply control system 1400 compares the power consumption of the entire power supply destination with the upper limit of consumable power, and notifies the image forming apparatus of the power that can be consumed by the image forming apparatus. Although an example in which communication is performed by power line communication (PLC) is described here, communication may be performed by wireless communication (Zigbee) or the like.

  In step S <b> 403, the image forming apparatus determines the print speed according to the consumable power permitted from the power supply control system 1400. If there is sufficient power that can be consumed, the normal print speed in S404 is selected. If the available power is insufficient to print at the normal print speed, the low-speed print operation in S405 is selected. If the available power is insufficient for printing at a low print speed, the print waiting operation in S406 is selected. Here, among the power consumed by each means during electrophotographic printing, the power consumed by the fixing heater of the fixing unit 206 is particularly large in the S26 fixing step, and the power consumption of the fixing heater can be reduced by slowing the printing speed. It becomes possible.

  If the normal print speed in S404 or the low-speed print operation in S405 is selected, the printout is performed and the operation ends. When the print waiting operation in S406 is selected, the process returns to S402, confirms again the power that can be consumed by the image forming apparatus with the power supply control system 1400, and waits until the power consumption that can be printed is permitted. When the printable power consumption is permitted, the image forming apparatus determines the print speed according to the power that can be consumed in S403, and thereafter performs the same operation.

  FIG. 5 is a flowchart showing an operation when a power reduction request is received from the power supply control system 1400 during printing in the printing operation of the image forming apparatus according to the present embodiment. FIG. 5 is a flow branched from printing at normal speed in S <b> 404 of FIG. 4.

  The power supply control system 1400 manages the power consumption of the entire power supply destination, and transmits a power reduction request to the image forming apparatus that is one of the power supply destinations according to the situation.

  When the image forming apparatus receives a power reduction request in step S502 during printing, the image forming apparatus recognizes power that can be consumed by the image forming apparatus in step S503.

  In step S <b> 504, the image forming apparatus determines an operation and a printing speed according to the power that can be consumed. If there is enough power available, printing at the normal printing speed in S505 is continued. If the available power is insufficient to print at the normal print speed, the power of the fixing heater is immediately halved even in the middle of the page in S506. By halving the power of the fixing heater, the power consumption of the entire image forming apparatus can be reduced to some extent. Further, since the fixing heater has a heat capacity, it can be fixed with residual heat to some extent.

  Here, the description will be made assuming that the page can be fixed normally if it is in the middle of one page. In step S509, the page being printed is output in a state where the power of the fixing heater is halved. In step S510, the print speed is changed to half, and the remaining pages are continuously printed out. When the print speed is halved, the control of each step S21 to S27 of the print process described in FIG. 2b is changed and the speed cannot be changed from the middle of the page. Therefore, the speed is changed from the next page. It is. When all pages are printed out in step S511, the process ends.

  Next, in S504, when the image forming apparatus determines the operation according to the power that can be consumed, if the power that can be consumed is not enough even if the print speed is halved, even in the middle of the page in S507, immediately. Turn off the fixing heater power. The power consumption of the entire image forming apparatus can be considerably reduced by turning off the power of the fixing heater. Further, since the fixing heater has a heat capacity, it can be fixed with residual heat to some extent. In step S521, the page in the middle of printing is output with the power of the fixing heater turned off.

  Next, in S522, it is determined whether or not the last page printed out is not defective in fixing. Fixing from the middle of the page is performed with residual heat while the power of the fixing heater is turned off, but whether the fixing is normal or abnormal varies depending on the situation. For example, if the black ratio of the image on the recording paper is high, more heat is required for melting. In addition, if the ambient temperature of the fixing heater is low, the temperature is rapidly lowered. The ambient temperature of the fixing heater is also affected by the air temperature and the continuous state of the printing operation until immediately before.

  The determination of whether or not the fixing is defective can be alternatively determined based on the control history of the fixing heater. Since the temperature of the fixing heater is controlled so as to be kept constant, it can be said from the history of applied power that if the applied power and the frequency of application are high, the temperature drop when the application to the heater is stopped is rapid. . Therefore, by creating a matrix table with these conditions as elements in advance, it is possible to determine whether or not the last page printed out in S522 has a fixing failure. If it is determined that the fixing is normal, the last output page is treated as a normal page in S523. In step S524, the process shifts to the standby mode, and print output for the next page and thereafter is interrupted.

  If it is determined in S522 that the fixing is defective, the last page output is discarded as a defective page in S532. In step S524, the process shifts to the standby mode, and print output for the next page and thereafter is interrupted. If the image forming apparatus includes a paper discharge sorter, the paper discharge destination may be changed depending on whether the page output in S523 is treated as a normal page or the page output in S532 is discarded as a defective page. It is done. If the image forming apparatus has a stamp function, the stamp is not pressed when the page output in S523 is treated as a normal page.

  When discarding the page output in S532 as a defective page, it may be possible to notify the user by pressing a stamp indicating invalidity or discard. In step S525, the power supply control system 1400 confirms power that can be consumed by the image forming apparatus, and waits until power consumption that can be printed is permitted. When the printable power consumption is permitted, if the page that was output last in S523 has not been discarded, the print output from the next page of the interrupted page is resumed in S526. In S525, the printable power consumption is permitted. If the last output page is discarded in S532, the print output is restarted from the reprint of the discarded page in S534. Then, the process returns to S504, the operation and the print speed are selected in accordance with the power that can be consumed, and the same operation is performed thereafter.

  If the power that can be consumed in S504 is not sufficient even if the fixing heater power is turned off, the power of the fixing heater is immediately turned off even in the middle of the page in S508. In step S521, a page in the middle of printing is output. In step S532, the last output page is discarded as a defective page. In step S533, the process shifts to the sleep mode, and print output for the next page and thereafter is interrupted. The power consumption of the entire image forming apparatus can be considerably reduced by turning off the power of the fixing heater and shifting the control means to the sleep mode.

  In the sleep mode, the process waits until receiving a notification permitting printable power consumption from the power supply control system 1400. When a notification of permitting printable power consumption is received in S525, print output is restarted from reprinting of the discarded page in S534. Then, the process returns to S504, the operation and the print speed are selected in accordance with the power that can be consumed, and the same operation is performed thereafter.

  FIG. 6 is a diagram illustrating a configuration example of a power supply system in which a switchboard as a power supply unit and an AC line as a power line are connected to an outlet as a power supply unit.

  In FIG. 6, 140 is a switchboard, 1400 is a power supply control system, and 1120 is an AC line. A printer, multifunction peripherals 1 to 3 as well as a PC, an air conditioner, a TV, and a refrigerator are connected via an outlet terminal portion.

101 control means, 110 image forming means, 130 power supply unit,
1301 power supply circuit unit, 1302 communication control unit, 1303 power supply management unit,
1400 Power Supply Control System (HEMS)

Claims (5)

A power consumption control method in a power supply control system comprising an image forming apparatus (100) having a power consumption control function and a power supply control system (1400) having a power supply function, the image forming apparatus and the power It is characterized by having a step of communicating between supply control systems to exchange power information with each other, and a step of controlling power consumption of the image forming apparatus. The image forming apparatus may be in a low power consumption state in accordance with power information from the power supply control system.
For this purpose, the image forming apparatus includes a communication control means (1302) for transmitting and receiving a power consumption restriction request and power consumption information from the power supply control system.
In accordance with the power that can be consumed by the image forming apparatus, the operation of each unit is controlled, and a power supply management unit (1303) that controls the power supplied to each unit is provided.
When printing is performed, one of the features is that the printing speed is changed in units of pages in accordance with the power that can be consumed.
Further, when it is necessary to reduce the power that can be consumed, one of the features is that the power supply to the fixing heater (206) is immediately stopped and printing is interrupted even during the printing page. .
One of the characteristics is that when the power supply to the fixing heater is stopped immediately in the middle of the page being printed, it is determined whether the page is good or bad due to a decrease in the fixing temperature, and if the page is defective, the page is discarded. When it is no longer necessary to reduce power consumption, one of the features is that print output is resumed from the next page after the last page that has been successfully printed, and a power consumption control method in the image forming apparatus, Supply system configuration and control method. When printing is paused during printing, pages that have been printed normally are ejected to the specified sorter, and pages that cannot be printed normally are sorted to another sorter to discard them. The power consumption control method for an image forming apparatus according to claim 1, and the configuration and control method of a power supply system, wherein pages that could not be printed are not sandwiched. When pausing in the middle of printing, the page that is expected to be able to print normally is printed without adding an image, and the page that is expected to be unable to print normally is a bad page so that it can be distinguished. 2. The method of controlling power consumption in an image forming apparatus according to claim 1, and the configuration and control method of a power supply system, wherein an image to be notified is added and printed out. Since the power that the image forming apparatus is allowed to consume is insufficient, the fuser heater power is cut off, and when the controller operates without shutting down, the user is notified of the situation. The power consumption control method for an image forming apparatus according to claim 1, and the configuration and control method of a power supply system. If the image forming device shifts to the sleep mode due to insufficient power allowed to be consumed, the user is informed that the shortage of power allowed to be consumed has been resolved and the device has shifted to the normal operation mode. The power consumption control method in the image forming apparatus according to claim 1, and the configuration and control method of a power supply system, wherein the notification is performed.