JP2008268326A - Image forming apparatus and power supply control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve power supply efficiency by dynamically switching an upper limit voltage to be supplied by a power supply in accordance with an image forming state.
[Solution]
In an image forming apparatus having a power source capable of supplying different voltages, the power mode supplied to a plurality of loads used for image formation is switched from the normal mode to the power saving mode or from the power saving mode to the normal mode (S502, S504). At this time, based on the switching state of the power mode, the power supply outputs an instruction to switch the voltage to be output from the high voltage to the low voltage or from the low voltage to the high voltage (S503, S505). .
[Selection] Figure 4

Description

  The present invention relates to an image forming apparatus capable of switching a power mode.

Conventionally, an image forming apparatus such as a copying machine has a function of automatically reducing power consumption and entering a standby mode (sleep mode) when an operation is not performed for a certain period of time. In such an image forming apparatus, in the standby mode, power consumption is suppressed by turning off the power other than the function for reacting to external inputs such as a network, a telephone line, and an operation panel. The following Patent Document 1 is disclosed as an image forming apparatus having a sleep mode.
JP 2003-307980 A

  By the way, when the supply power of the power supply device provided in the image forming apparatus is large, there is a problem that the power supply efficiency is deteriorated as compared with the case where the power consumption is small as in the standby mode.

  That is, if the efficiency is increased when the power consumption in the image forming apparatus main body is small, there is a problem that the supplied power is reduced.

  In order to solve this, there is a method in which a power supply with a large supply power for normal operation and a power supply with a small supply power for standby mode are provided, and these power supplies are combined to increase power supply efficiency. However, there is a problem in that the cost increases when the image forming apparatus is provided with two power sources independently in advance.

  The present invention has been made in order to solve the above-described problems, and an object of the present invention is a mechanism capable of dynamically switching the upper limit voltage to be supplied by the power supply and improving the power supply efficiency in accordance with the image forming state. Is to provide.

  The image forming apparatus of the present invention that achieves the above object has the following configuration.

  An image forming apparatus including a power source capable of supplying different voltages, and a switching unit that switches a power mode supplied to a plurality of loads used for image formation from the normal mode to the power saving mode, or from the power saving mode to the normal mode, Power control means for outputting, to the power supply, an instruction to switch a voltage to be output from the power supply from a high voltage to a low voltage or from a low voltage to a high voltage based on the switching state of the power mode. To do.

  According to the present invention, an inexpensive image forming apparatus capable of improving power supply efficiency by dynamically switching an upper limit voltage to be supplied by a power supply according to an image forming state.

  Next, the best mode for carrying out the present invention will be described with reference to the drawings.

<Description of system configuration>
[First Embodiment]
FIG. 1 is a block diagram illustrating the configuration of an image forming apparatus according to the first embodiment of the present invention. In this embodiment, an image input / output system that performs image processing through communication between a reader unit and a printer unit is taken as an example. However, a printer device or an analog image forming device may be used.

  In FIG. 1, a reader unit (image input device) 200 optically reads a document image and converts it into image data. The reader unit 200 includes a scanner unit having a function for reading a document and a document feeding unit having a function for transporting a document sheet.

  A printer unit (image output device) 300 conveys recording paper, prints image data as a visible image thereon, and discharges the recording paper out of the device. The printer unit 300 includes a paper feed unit 360 having a plurality of types of recording paper cassettes, and a marking unit 310 having a function of transferring and fixing image data onto the recording paper. In addition, the printer unit 300 includes a paper discharge unit 370 that has a function of sorting and stapling printed recording papers and outputting them to the outside of the apparatus.

  The control device 100 is electrically connected to the reader unit 200 and the printer unit 300, and further connected to the host computer 15 and the servers 13 to 14 via the network 11.

  The marking unit 310 includes various power loads, and each power load receives a power supply from the power supply unit 400 and performs a predetermined image forming operation. Here, the power load includes a photosensitive drum, a paper feed roller, a motor for supplying driving force to a driving roller for driving a conveying belt, a heater for heating a thermal fixing unit, and the like. Of course, when an optional unit is connected, it is necessary to supply power to more loads.

  Note that the image input / output system shown in the present embodiment includes a normal power mode for performing image formation and a power saving mode for waiting for image formation, and performs power saving control. The condition for the power mode to shift to the power saving mode varies depending on the function of the image input / output system 10 and user settings.

  The control device 100 controls the reader unit 200 to read the image data of the original, and controls the printer unit 300 to output the image data to a recording sheet to provide a copy function.

  The image input / output system 10 includes a scanner function that converts image data read from the reader unit 200 into code data and transmits the code data to the various servers 12 to 14 via the network 11. The image input / output system 10 provides a printer function that converts code data received from the host computer 15 via the network 11 into image data and outputs the image data to the printer unit 300.

  The power supply unit 400 includes a power supply circuit that receives an AC commercial power supply (AC power supply) as an input. The power supply unit 400 creates a voltage 402 that supplies a DC voltage or an AC voltage to the control device 100, the reader unit 200, and the printer unit 300. Further, the power supply unit 400 changes the voltage of the DC voltage in accordance with a control signal 401 from the control device 100 as described later.

  The OFF / ON switching circuits 410 and 420 turn OFF / ON the power supplied to the reader unit 200 and the printer unit 300 in response to a supply signal from the control device 100.

<Description of control device>
FIG. 2 is a block diagram illustrating the configuration of the control device 100 shown in FIG. In addition, the same code | symbol is attached | subjected to the same thing as FIG.

  2, the main controller 110 mainly includes a CPU 111, a memory control unit 112, a bus control unit 113, a scan I / F 114, a printer I / F 115, and a panel I / F 116. Further, the main controller 110 includes a scan image processing unit 117, a printer image processing unit 118, a compression / decompression unit 119, a wireless I / F unit 120, a serial I / F unit 121, and a port control unit 122. Reference numeral 143 denotes a connector to which a USB cable is connected.

  The CPU 110 and the memory control unit 112 control the overall operation of the control device 100, and the CPU 111 operates based on a program stored in the memory 131.

  The program stored in the memory 131 also describes an operation of interpreting PDL (page description language) code data received from the host computer 15 and developing it into raster image data. The CPU 111 interprets code data and develops raster image data by executing the program.

  The memory control unit 112 controls data transfer input / output from each I / F, and controls arbitration at the time of bus contention and DMA data transfer.

  The bus control unit 113 controls access to the boot ROM 132, the ROM 133, and the modem 134. The scan I / F 114 receives image data input from the scanner, and transfers the image data to the memory 131 and the scan image processing unit 117.

  The scan image processing unit 117 has a function of performing predetermined image processing on the image received from the scan I / F 114. Here, examples of the predetermined image processing include line pitch correction, offset correction, nonlinear correction, color space matching, MTF correction, spatial filter, and achromatic color determination.

  The printer I / F 115 creates a control signal based on the video control signal sent from the printer unit, and outputs a video signal in accordance with the control signal.

  The printer image processing unit 118 inputs raster image data from the memory 131 or the compression / decompression unit 119, and outputs halftoned image data to any of the memory 131, the compression / decompression unit 119, and the printer I / F 115. .

  Here, examples of the image processing include color space compression, background removal, log conversion, nonlinear color space conversion, random number addition, gamma conversion, error diffusion processing, and screen processing.

  The compression / decompression unit 119 compresses the raster image data stored in the memory 131 by a method such as MH / MR / MMR / JBIG / JPEG, and conversely decompresses the code data compressed and stored into raster image data. .

  The scaling / rotation unit 123 has a function of performing enlargement / reduction processing and 90 °, 180 °, and 270 ° rotation processing on the raster image data stored in the memory 131. The BootROM 132 stores a program for the CPU 111.

  The ROM 133 is used to store user mode and various setting information, and the Font ROM is also stored in the ROM 133.

  Panel I / F 116 communicates with operation panel 140. The operation panel 140 has a liquid crystal display unit and a plurality of hard keys. A signal input from the hard key is transmitted to the CPU 111 via the panel I / F 116 described above, and the operation panel 140 displays data sent from the panel I / F 116. The operation panel 140 is composed of, for example, a liquid crystal display unit, and displays functions and the like in the operation of the image forming apparatus as a user interface (UI). The operation panel 140 is also supplied with power from the power supply unit 400.

  The wireless I / F 120 performs communication with a host computer and communication with various devices. The wireless I / F generally includes a wireless LAN.

  In the serial I / F 121, communication with the host computer and communication with various devices are performed via the connector 143. A USB is generally used as the serial bus. The host computer performs communication processing via a printer driver and utility.

  The wireless I / F 120 and the serial I / F 121 are used for an I / F that receives PDL data from a host computer, command communication with the display device 18, image data transfer, and the like.

  The modem 146 and the NCU 135 are connected to a public line and perform FAX communication control. The network controller 137 is connected to an external network. The network is generally Ethernet (registered trademark), and is used for receiving PDL data from a host computer, transmitting a scanner image, remote management, and the like.

  The real time clock module 136 is for updating / saving the date and time managed in the device, and is backed up by a backup battery.

<Description of power control>
FIG. 3 is a block diagram illustrating a configuration of a power control unit including the power supply unit 400 illustrated in FIG. 1 and 2 are denoted by the same reference numerals. Note that one power supply unit 400 is configured to be able to supply a high voltage or a low voltage to a load according to the state of the image forming apparatus. Therefore, the power supply unit 400 functions as a power supply unit including both a high load power source and a high efficiency power source (low load power source). The power supply state of the power supply unit 400 is switched and controlled by the power supply control unit 151 based on an image forming state shown in FIG.

  In FIG. 3, the constant voltage power supply 150 converts the DC voltage input from the power supply unit 400 into a constant voltage supplied to each unit. Here, the constant voltage power source 150 converts the voltage into a different voltage depending on each device, for example, a DC voltage such as DC 24V, DC 5V, or the like.

  Here, the power supply unit 400 switches between a high voltage required for normal operation of the reader unit 200 or the printer unit 300 and a low voltage supplied to the control device 100 when the reader unit 200 or the printer unit 300 shifts to the power saving mode state. It is a possible power supply unit.

  The OFF / ON switching circuit 153 performs OFF / ON switching control on the supply of the DC voltage input from the constant pressure power supply 150 according to the control signal 165 fed back from the main controller 110.

  The power supply control unit 151 outputs a control signal 401 to the power supply unit 400 according to the control signals 161 to 166 fed back from each device. This control signal 401 becomes an instruction signal for shifting the voltage supplied from the power supply unit 400 from the high voltage state to the low voltage state or from the low voltage to the high voltage state.

  The control signal 166 is a signal controlled from the main controller 110 and is output when the DC voltage output from the power supply unit 400 is switched from a high voltage to a low voltage.

  The control signal 165 is a control signal output from the power supply control unit 151 to the OFF / ON switching circuit 153. The power supply control unit 151 outputs a control signal 165 to the OFF / ON switching circuit 153 as a control signal that is turned on when the DC voltage output from the power supply unit 400 is high and turned off when the DC voltage is low. Thereby, it is possible to perform control to switch the DC voltage output from the power supply unit 400 from a low voltage to a high voltage.

  Here, the control signals 161 to 164 function as trigger signals fed back from each unit to the power supply control unit 151. Each of the control signals 161 to 164 triggers the power control unit 151 at a timing synchronized with a power saving return operation from the operation panel 140, reception of a FAX, reception of a network, timer / alarm interruption from the RealTime Clock, and the like.

<Description of power control flow>
FIG. 4 is a flowchart showing a power supply control procedure in the image forming apparatus showing the present embodiment. This example corresponds to a power control procedure for the power supply unit 400.

  S501 to S505 indicate each step. Each step is realized by the CPU 111 loading a control program stored in the ROM 133 into the memory 131 and executing it.

  In step S501, when power is turned on by the power switch, a high voltage is output from the power supply unit 400 to the load and device constituting the image forming apparatus. As a result, the OFF / ON switching circuit 153 (including the OFF / ON switching circuits 410 and 420) is turned on. Then, power is supplied to the reader unit 200, the control device 100, and the printer unit 300 to enter the normal operation mode.

  Next, in S502, the CPU 111 monitors power saving mode transition conditions. Here, the power saving transition condition includes conditions such that there is no operation instruction from the operation panel 140 for a certain period of time, a print job such as PDL or FAX is not received, and data transfer is not performed on the network. It is done. Note that the power saving transition condition may include a configuration in which different conditions are set according to the function usage environment of the user and the immediately preceding image forming operation.

  If the CPU 111 determines in S502 that the conditions for shifting to the power saving mode are satisfied, the power control unit 151 outputs an instruction to switch to a lower voltage from the power control unit 151 in S503. As a result, the power supply unit 400 is shifted from the normal power mode to the power saving mode. In the power saving mode, the OFF / ON switching circuit 153 is turned off. As a result, as shown in FIG. 1, the power supply to the reader unit 200 and the printer unit 300 is restricted, thereby entering the power saving mode. However, as shown in FIG. 1, power supply to the control device 100 is not stopped even during the power saving mode.

  In step S504, the CPU 111 monitors whether a trigger signal for shifting from the power saving mode to the normal operation mode is input. Here, the trigger signal includes a control signal 161, a return instruction from the operation panel 140, reception of the control signal 162, FAX, a control signal 163, a return instruction from the network, a control signal 164, a timer / alarm interrupt from the RealTimeClock, etc. is there. The trigger signal may be generated by detecting that a communication cable is connected to the connector 143, for example.

  In step S504, when the power supply control unit 151 detects that any of the trigger signals is input, the power supply control unit 151 issues an instruction (control signal 401 shown in FIG. 3) to switch the output voltage to a higher voltage. . Next, the OFF / ON switching circuit 153 is turned on to shift from the power saving mode to the normal operation mode, and the process returns to S502.

  Accordingly, it is possible to increase the voltage to cope with a high load when the power consumption in the normal operation mode is large, and to improve the efficiency by reducing the voltage when the power consumption in the power saving mode is small.

  Therefore, the image input / output system 10 does not need to have a high load power source and a high efficiency power source in advance, and the cost of the power supply unit can be reduced.

  According to the present embodiment, when the power mode of the image input / output system 10 changes in accordance with the image forming state, the upper limit voltage to be supplied by the power supply is dynamically switched in accordance with the change to improve the power supply efficiency. Can do.

[Second Embodiment]
In the above embodiment, the case where both the OFF / ON switching circuits 410 and 420 are simultaneously supplied when the voltage is supplied from the power supply unit 400 has been described. However, in S504 shown in FIG. 4, it may be controlled to maintain the power saving state by supplying a voltage only to the OFF / ON switching circuit 410 according to the factor to shift to the normal mode.

  That is, the power saving state is maintained as in the case of receiving a job that does not need to drive the printer unit 300, transmitting a document from the reader unit 200, or simply storing a scanned document in the memory device. This is because there is a case where it is possible.

[Third Embodiment]
Also, when a communication cable is connected to the connector 143 and a job processing request is received from the host computer, the voltage supply state may be controlled by determining the attribute of the job processing request as in the second embodiment. . In other words, the power saving may be controlled to maintain the state by turning on both of the OFF / ON switching circuits 410 and 420 at the same time or turning on only one of them.

  In particular, when the request from the host computer 15 is not always a print job, it is important to determine the attribute of the factor for shifting to the normal mode in S504 of FIG.

[Fourth Embodiment]
The configuration of a data processing program that can be read by the image forming apparatus according to the present invention will be described below with reference to the memory map shown in FIG.

  FIG. 5 is a diagram illustrating a memory map of a storage medium that stores various data processing programs readable by the image forming apparatus according to the present invention.

  Although not particularly illustrated, information for managing a program group stored in the storage medium, for example, version information, creator, etc. is also stored, and information depending on the OS on the program reading side, for example, a program is identified and displayed. Icons may also be stored.

  Further, data depending on various programs is also managed in the directory. In addition, a program for installing various programs in the computer, and a program for decompressing when the program to be installed is compressed may be stored.

  The functions shown in FIG. 4 in this embodiment may be performed by the host computer by a program installed from the outside. In this case, the present invention is applied even when an information group including a program is supplied to the output device from a storage medium such as a CD-ROM, a flash memory, or an FD, or from an external storage medium via a network. Is.

  As described above, the storage medium storing the software program code for realizing the functions of the above-described embodiments is supplied to the system or apparatus. It goes without saying that the object of the present invention can also be achieved by the computer (or CPU or MPU) of the system or apparatus reading and executing the program code stored in the storage medium.

  In this case, the program code itself read from the storage medium realizes the novel function of the present invention, and the storage medium storing the program code constitutes the present invention.

  Therefore, as long as it has the function of the program, the form of the program such as an object code, a program executed by an interpreter, or script data supplied to the OS is not limited.

  As a storage medium for supplying the program, for example, a flexible disk, hard disk, optical disk, magneto-optical disk, MO, CD-ROM, CD-R, CD-RW, magnetic tape, nonvolatile memory card, ROM, DVD, etc. Can be used.

  In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention.

  As another program supply method, a browser on a client computer is used to connect to an Internet home page. Then, the computer program itself of the present invention or a compressed file including an automatic installation function can be downloaded from the homepage by downloading it to a recording medium such as a hard disk. It can also be realized by dividing the program code constituting the program of the present invention into a plurality of files and downloading each file from a different homepage. That is, a WWW server, an ftp server, and the like that allow a plurality of users to download a program file for realizing the functional processing of the present invention on a computer are also included in the claims of the present invention.

  In addition, the program of the present invention is encrypted, stored in a storage medium such as a CD-ROM, distributed to users, and key information for decryption is downloaded from a homepage via the Internet to users who have cleared predetermined conditions. Let It is also possible to execute the encrypted program by using the key information and install the program on a computer.

  In addition, the functions of the above-described embodiments are not only realized by executing the program code read by the computer. For example, based on an instruction of the program code, an OS (operating system) running on the computer performs part or all of the actual processing. Needless to say, the process includes the case where the functions of the above-described embodiments are realized.

  Further, the program code read from the storage medium is written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer. After that, based on the instruction of the program code, the CPU of the function expansion board or function expansion unit performs part or all of the actual processing, and the function of the above-described embodiment is realized by the processing. Needless to say.

  The present invention is not limited to the above embodiments, and various modifications (including organic combinations of the embodiments) are possible based on the spirit of the present invention, and these are excluded from the scope of the present invention. is not.

  While various examples and embodiments of the present invention have been shown and described, the spirit and scope of the present invention are not limited to the specific descriptions in the present specification by those skilled in the art.

1 is a block diagram illustrating a configuration of an image forming apparatus according to a first embodiment of the present invention. It is a block diagram explaining the structure of the control apparatus shown in FIG. It is a block diagram explaining the structure of the power supply control part containing the power supply part shown in FIG. 6 is a flowchart illustrating a power control procedure in the image forming apparatus according to the present exemplary embodiment. It is a figure explaining the memory map of the storage medium which stores the various data processing program which can be read with the image forming apparatus which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image input / output system 100 Control apparatus 151 Power supply control part 200 Reader part 300 Printer part 400 Power supply part

Claims (3)

An image forming apparatus including a power source capable of supplying different voltages,
Switching means for switching the power mode supplied to a plurality of loads for image formation from the normal mode to the power saving mode, or from the power saving mode to the normal mode;
Based on the switching state of the power mode, power supply control means for outputting an instruction to switch the voltage to be output from the power supply from a high voltage to a low voltage, or from a low voltage to a high voltage, to the power supply,
An image forming apparatus comprising:   2. The image forming apparatus according to claim 1, wherein the plurality of loads include a reader unit that reads a document and a printer unit that outputs image data to a recording medium. A power supply control method for an image forming apparatus including a power supply capable of supplying different voltages,
A switching step of switching the power mode supplied to a plurality of loads used for image formation from the normal mode to the power saving mode, or from the power saving mode to the normal mode;
A power supply control step of outputting an instruction to the power supply to switch the voltage to be output from the high voltage from a high voltage to a low voltage or from a low voltage to a high voltage based on the switching state of the power mode;
A power supply control method characterized by comprising:

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