Patent Publication Number: US-2020301628-A1

Title: Image forming apparatus and power supply control method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation of application Ser. No. 16/358,833 filed on Mar. 20, 2019, the entire contents of which are incorporated herein by reference. 
    
    
     FIELD 
     Embodiments described herein relate generally to an image forming apparatus and a power supply control method. 
     BACKGROUND 
     In the related art, an image forming apparatus that has a function of a Super-Sleep mode for power saving is disclosed. This image forming apparatus has a function of automatically waking up when receiving a packet from a network in the Super-Sleep mode. This function is not valid in response to the reception of any packet but is valid only when the received packet is a packet of print data. Accordingly, in the image forming apparatus, it is necessary to determine whether or not the received packet is the packet of print data. However, in the related art, data of a packet cannot be verified until various hardware components (HWs) (memory, auxiliary storage device, application specific integrated unit (ASIC), central processing unit (CPU)) wake up. Therefore, warm-up cannot start until various kinds of HWs wake up, and the start of printing may be delayed by the time required for various HWs to wake up. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating a configuration of a power supply control system according to an embodiment; 
         FIG. 2  is a block diagram illustrating a hardware configuration of an information processing apparatus; 
         FIG. 3  is a diagram illustrating an example of data of a packet generated by the information processing apparatus; 
         FIG. 4  is a block diagram illustrating a hardware configuration of an image forming apparatus; 
         FIG. 5  is a sequence diagram illustrating a processing flow of a previous setting when the power supply control system shifts to a Sleep mode; and 
         FIG. 6  is a sequence diagram illustrating a processing flow of waking up the power supply control system from a Super-Sleep mode. 
     
    
    
     DETAILED DESCRIPTION 
     In general, according to one embodiment, an image forming apparatus includes a printer unit, a first controller, a power supply unit, and a second controller. The printer unit forms an image on a sheet. The first controller performs a control of shifting a state of the apparatus from a normal mode to a power saving mode. The power supply unit supplies power to the first controller and the printer unit during the normal mode and supplies power to the first controller and stops power supply to the printer unit during the power saving mode. The second controller performs a power supply control on the printer unit before performing a power supply control on the first controller when a packet received during the power saving mode includes specific information indicating a print job. 
     Hereinafter, the image forming apparatus and the power supply control method according to the embodiment will be described. 
       FIG. 1  is a diagram illustrating a configuration of a power supply control system  10  according to the embodiment. 
     The power supply control system  10  includes an information processing apparatus  50  and an image forming apparatus  100 . The information processing apparatus  50  and the image forming apparatus  100  are communicatively connected to each other through a network  150 . The network  150  may be a network having any configuration. Examples of the network  150  include a wireless local area network (LAN) and the Internet. 
     The information processing apparatus  50  generates a packet to be transmitted to the image forming apparatus  100  in response to an operation of a user. For example, when a print instruction is received from the user, the information processing apparatus  50  generates a packet including print data. At this time, the information processing apparatus  50  generates the packet by setting a specific character string (hereinafter, referred to as “print character string”) indicating that the packet is a print instruction to a portion close to the beginning of the packet. The portion close to the beginning of the packet refers to a portion closer to the beginning than actual data indicating a print target. The specific information indicating that the packet is the print instruction is not limited to a character string and may be information of a code. The information processing apparatus  50  is configured using an information processing apparatus such as a personal computer, a laptop computer, a tablet terminal, or a smartphone. 
     The image forming apparatus  100  is a multi-function peripheral (MFP) that can read a sheet and can form a toner image on a sheet. The sheet may be, for example, paper on which an original document, a character, an image, or the like is printed. 
     The image forming apparatus  100  has a function of a Super-Sleep mode. The Super-Sleep mode is an example of a power saving mode. The Super-Sleep mode is a mode that realizes power saving. The image forming apparatus  100  is controlled as follows in the Super-Sleep mode.
         Stops supplying power to an image reading device, the printer unit, and the like   Continues to supply power to a main memory and holds a state of the main memory   Stops power supply to an auxiliary storage device   Shifts a CPU to a Deep-Sleep mode       

     The Deep-Sleep mode is a mode in which the voltage is reduced to a minimum value required to operate the CPU. 
     When the image forming apparatus  100  operates in the Super-Sleep mode, the image forming apparatus  100  controls wake-up of the printer unit based on the character string of a specific portion included in the packet. The image forming apparatus  100  compares the character string of the specific portion to a pre-stored character string and, when the character strings match with each other, wakes up the printer unit including a fixing unit before system wake-up. The pre-stored character string includes at least the print character string. Here, “before system wake-up” represents “before all the functional units of the image forming apparatus  100  wake up from the Super-Sleep mode”. 
     For example, the pre-stored character string may be the print character string. For example, when a packet to be transmitted from the information processing apparatus  50  includes the print character string, the pre-stored character string may be the same as a character string ranging from the beginning of the packet to the print character string. This way, when the packet transmitted from the information processing apparatus  50  is the print instruction, the image forming apparatus  100  wakes up the printer unit before waking up all the operating systems (OS). 
     The image forming apparatus  100  compares the character string of the specific portion to the pre-stored character string and, when the character strings do not match with each other, does not wake up the printer unit. That is, when the packet to be transmitted from the information processing apparatus  50  does not include the print character string, the image forming apparatus  100  does not wake up the printer unit. The case where the packet does not include the print character string may be, for example, a case where the packet includes a character string indicating Hold printing to be stored in a main body or a character string indicating an input to a Box. The image forming apparatus  100  also does not wake up the printer unit when accessed to a port for setting. 
       FIG. 2  is a block diagram illustrating a hardware configuration of the information processing apparatus  50 . 
     The information processing apparatus  50  includes an operation unit  51 , a display  52 , a network interface  53 , a memory  54 , an auxiliary storage device  55 , and a CPU  56 . The respective functional units are connected to each other through a system bus  60  to be capable of data communication. 
     The operation unit  51  receives the operation of the user. The operation unit  51  outputs a signal corresponding to the operation input by the user to the CPU  56 . The operation unit  51  may be configured as a touch panel integrated with the display  52 . 
     The display  52  is an image display device such as a liquid crystal display or an organic electro luminescence (EL) display. The display  52  displays various information related to the information processing apparatus  50 . The display  52  outputs a signal corresponding to the operation input by the user to the CPU  56 . 
     The network interface  53  transmits and receives data to and from another apparatus. Here, the other apparatus is, for example, the image forming apparatus  100 . The network interface  53  operates as an input interface and receives data or an instruction transmitted from the other apparatus. The network interface  53  operates as an output interface and transmits the packet to the other apparatus. 
     The memory  54  temporarily stores data used in each of the functional units included in the information processing apparatus  50 . The memory  54  is, for example, a RAM. The memory  54  may temporarily store a packet as a transmission target. 
     The auxiliary storage device  55  is, for example, a hard disk or a solid state drive (SSD) and stores various data. The various data includes, for example, a software program and image information. The software program is, for example, a program of a software such as an OS or a printer driver. 
     The CPU  56  controls the operations of various functional units of the information processing apparatus  50 . The CPU  56  loads the software program stored in the auxiliary storage device  55  on the memory  54  and executes the software program to execute the process. For example, when the instruction input through the operation unit  51  is the print instruction, the printer driver generates a packet by setting the print character string to a portion close to the beginning of the packet. 
       FIG. 3  is a diagram illustrating an example of data of a packet  70  generated by the information processing apparatus  50 . 
     The data of the packet  70  illustrated in  FIG. 3  is data of a packet generated when the print instruction is given. When the print instruction is given, a character string “PRINTMODE=NORMAL” is set as shown in a region  71 . In the case of Hold printing, the character string shown in the region  71  becomes a character string “PRINTMODE=HOLD”. When the instruction indicating an input to the Box is given, the character string shown in the region  71  becomes a character string “PRINTMODE=BOX”. 
     The character string from the beginning of the packet  70  to the character string indicating the print mode (for example, “PRINTMODE=***”) is a target for comparison to the pre-stored character string. In  FIG. 3 , the image forming apparatus  100  compares the following character string to the pre-stored character string. 
     “%-12345X@PJL COMMENT TOSHIBA V4 Printer¥n@PJL COMMENT DSSC PRINT PRINTMODE=NORMAL” 
       FIG. 4  is a block diagram illustrating a hardware configuration of the image forming apparatus  100 . 
     The image forming apparatus  100  includes a display  110 , a control panel  120 , a printer unit  130 , a sheet accommodation unit  140 , an image reading device  200 , a network interface  310 , an auxiliary storage device  320 , a memory  330 , a CPU  340 , a microcomputer  350 , and a power supply unit  360 . The respective functional units are connected to each other through a system bus  15  to be capable of data communication. 
     The display  110  is an image display device such as a liquid crystal display or an organic EL display. The display  110  displays various information related to the image forming apparatus  100 . The display  110  outputs a signal corresponding to the operation input by the user to the CPU of the image forming apparatus  100 . The display  110  receives the operation of the user. 
     The control panel  120  includes a plurality of buttons. The control panel  120  receives the operation of the user. The control panel  120  outputs a signal corresponding to the operation input by the user to the CPU of the image forming apparatus  100 . The display  110  and the control panel  120  may be integrated into a touch panel. 
     The printer unit  130  executes an image forming process. In the image forming process, the printer unit  130  forms an image on a sheet based on image information generated by the image reading device  200  or image information received through a communication path. The printer unit  130  includes an image forming unit and a fixing unit. 
     The sheet accommodation unit  140  accommodates sheets to be used for forming image in the printer unit  130 . 
     The image reading device  200  reads an image of a reading target in the form of brightness of light. For example, the image reading device  200  reads an image that is printed on the sheet of the reading target set on an original document reading mount. The image reading device  200  records the read image information. The recorded image information may be transmitted to another information processing apparatus through the network. Based on the recorded image information, the printer unit  130  may form an image on the sheet. 
     The network interface  310  transmits and receives data to and from another apparatus. Here, the other apparatus is, for example, the information processing apparatus  50 . The network interface  310  operates as an input interface and receives data or an instruction transmitted from the other apparatus. Examples of an instruction to be transmitted from the other apparatus include a print execution instruction and an image information storage instruction. The network interface  310  operates as an output interface and transmits data to the other apparatus. 
     The auxiliary storage device  320  is, for example, a hard disk or a solid state drive (SSD) and stores various data. The various data includes, for example, a software program, digital data, a job, and a job log. The software program is, for example, a program of a software such as an OS, a device driver, or a network system manager (NSM). The NSM is a software for managing the network. 
     The memory  330  temporarily stores data used in each of the functional units included in the image forming apparatus  100 . The memory  330  is, for example, a RAM. The memory  330  may store the digital data generated by the image reading device  200 . The memory  330  may temporarily store any one of the job and the job log. 
     The CPU  340  controls the operations of various functional units of the image forming apparatus  100 . The CPU  340  loads the software program stored in the auxiliary storage device  320  on the memory  330  and executes the software program to execute the process. Here, an example of a specific process of the CPU  340  will be described. When a condition of shifting to the Super-Sleep mode is satisfied, the CPU  340  shifts the mode of the apparatus from the normal mode to the Super-Sleep mode. For example, when a predetermined time instruction is not input or when a predetermined time zone is reached, the CPU  340  determines that the condition of shifting to the Super-Sleep mode is satisfied. The CPU  340  is an aspect of the first controller. 
     When a specific character string indicating the print job is described in the packet received in the Super-Sleep mode, the microcomputer  350  performs a power supply control on the printer unit  130 . The microcomputer  350  includes a memory or an auxiliary storage device. The auxiliary storage device of the microcomputer  350  stores a firmware software program of a network interface card (NIC) or a character string as a target for comparison. The microcomputer  350  loads the firmware software program stored in the auxiliary storage device on the memory and executes the software program to execute the process. The microcomputer  350  uses less power than the CPU  340 . The microcomputer  350  is an aspect of the second controller. 
     Here, an example of a specific process of the microcomputer  350  will be described. The microcomputer  350  compares the character string of the specific portion to the pre-stored character string and, when the character strings match with each other, performs the power supply control on the printer unit  130 . More specifically, the microcomputer  350  wakes up the printer unit  130  before the system wake-up by performing the power supply control on the printer unit  130  before performing the power supply control on the CPU  340 . 
     The power supply unit  360  is connected to a commercial power supply and supplies power from the commercial power supply to each of the functional units. For example, the power supply unit  360  supplies power to each of the functional units in the normal mode. The power supply unit  360  supplies a minimum necessary amount of power for operation to the CPU  340  in the Super-Sleep mode. The power supply unit  360  stops the power supply to the printer unit  130 , the image reading device  200 , and the auxiliary storage device  320  in the Super-Sleep mode. Here, the reason why the minimum necessary amount of power for operation is supplied to the CPU  340  is that an amount of power for operating the CPU  340  in the Deep-Sleep mode is required. The power supply unit  360  supplies power according to the control of the CPU  340 . Regardless of any mode, the power supply unit  360  supplies power to the memory  330 , the microcomputer  350 , and the network interface  310 . 
       FIG. 5  is a sequence diagram illustrating a processing flow of a previous setting when the power supply control system  10  is shifted to the Sleep mode. The process illustrated in  FIG. 5  is executed when the condition of shifting to the Super-Sleep mode is satisfied. 
     The NSM that is operating on the CPU  340  checks a setting of a main body (ACT  101 ). Specifically, when a user authentication setting is ON as a setting of the apparatus, the NSM checks, for example, a setting in which the printer unit  130  does not wake up before the system wake-up. Next, after the setting check, the NSM generates a setting notification including the result of the setting check and a wake-up condition for waking up the apparatus from the Super-Sleep mode (ACT  102 ). 
     The wake-up condition is that the packet is received from a printer port. The wake-up condition may be set in advance and stored in the auxiliary storage device  320 . For example, the result of the setting check is information indicating whether the power supply to the printer unit  130  before the system wake-up is valid or invalid. The NSM outputs the generated setting notification to the device driver (ACT  103 ). 
     The device driver acquires the setting notification output from the NSM. The device driver stores the result of the setting check and the wake-up condition included in the acquired setting notification (ACT  104 ). Next, the device driver notifies the wake-up condition to the microcomputer  350  (ACT  105 ). The microcomputer  350  stores the wake-up condition output from the device driver in the memory (ACT  106 ). 
     Next, the image forming apparatus  100  shifts to the Super-Sleep mode (ACT  107 ). Specifically, first, the CPU  340  controls the power supply unit  360  to stop power supply to the printer unit  130 , the image reading device  200 , and the auxiliary storage device  320 . Next, the CPU  340  controls the power supply unit  360  such that the amount of power supplied to the apparatus is an amount only enough for operating the apparatus in the Deep-Sleep mode. 
       FIG. 6  is a sequence diagram illustrating a processing flow of waking up the power supply control system  10  from the Super-Sleep mode. It is assumed that the image forming apparatus  100  is in the Super-Sleep mode when the process of  FIG. 6  starts. 
     When an instruction is received from the user (ACT  201 ), the operation unit  51  of the information processing apparatus  50  outputs the received instruction to the CPU  56 . The CPU  56  analyzes the instruction input through the operation unit  51 . Specifically, the CPU  56  analyzes whether the input instruction is the print instruction or another instruction. Here, it is assumed that the input instruction is the print instruction. 
     In this case, the CPU  56  generates a packet including the print character string (ACT  202 ). At this time, the printer driver of the CPU  56  generates the packet by setting the print character string to a portion close to the beginning of the packet. Here, it is assumed that the printer driver generates the packet  70  illustrated in  FIG. 3 . The printer driver transmits the packet to the image forming apparatus  100  through the network interface  53  (ACT  203 ). 
     The network interface  310  of the image forming apparatus  100  receives the packet transmitted from the information processing apparatus  50 . The network interface  310  outputs the received packet to the microcomputer  350  (ACT  204 ). The microcomputer  350  determines whether the stored wake-up condition is satisfied based on the packet output from the network interface  310  (ACT  205 ). Specifically, when the packet is received from the printer port (for example, Port  9100 ), the microcomputer  350  determines that the wake-up condition is satisfied. On the other hand, when the packet is received from a port other than the printer port (for example, Port  9100 ), the microcomputer  350  determines that the wake-up condition is not satisfied. When the wake-up condition is satisfied, the microcomputer  350  checks the content of the packet. On the other hand, when the wake-up condition is not satisfied, the microcomputer  350  deletes or temporarily stores the packet. Here, it is assumed that the wake-up condition is satisfied. 
     Since the wake-up condition is satisfied, the microcomputer  350  subsequently extracts a character string from the beginning to a character string indicating the print mode from the character string included in the packet. In this case, the microcomputer  350  extracts the following character string. 
     “%-12345X@PJL COMMENT TOSHIBA V4 Printer¥n@PJL COMMENT DSSC PRINT PRINTMODE=NORMAL” 
     Next, the microcomputer  350  acquires a character string as a target for comparison that is stored in the auxiliary storage device included in the microcomputer  350 . Here, the character string as a target for comparison is as follows. 
     “%-12345X@PJL COMMENT TOSHIBA V4 Printer¥n@PJL COMMENT DSSC PRINT PRINTMODE=NORMAL” 
     Next, the microcomputer  350  compares the character string extracted from the packet to the character string as the target for comparison. In the above example, the character strings match with each other. In this case, the microcomputer  350  outputs a wake-up instruction as an interrupt instruction to the device driver of the CPU  340  (ACT  206 ). As a result, the device driver wakes up from the Deep-Sleep mode (ACT  207 ). At this time, only the minimum necessary amount of power is supplied to the CPU  340 , and the NSM or the OS does not wake up. The power supply from the power supply unit  360  to the printer unit  130 , the image reading device  200 , and the auxiliary storage device  320  is stopped. 
     The device driver checks the setting notified at the setting notification (ACT  208 ). At this time, when the wake-up of the printer unit  130  before the system wake-up is invalid, the device driver wakes up the system before waking up the printer unit  130 . Specifically, first, the device driver starts power supply from the power supply unit  360  to the image reading device  200 , the auxiliary storage device  320 , and the CPU  340 . Next, the device driver wakes up the OS and wakes up various HW such as ASIC or the auxiliary storage device  320 . Next, the device driver wakes up the printer unit  130  by starting power supply from the power supply unit  360  to the printer unit  130 . 
     On the other hand, when the wake-up of the printer unit  130  before the system wake-up is valid, the device driver wakes up the printer unit  130  before the system wake-up. Specifically, the device driver sets a B-Power port for restarting power supply to the fixing unit of the printer unit  130  to ON (ACT  209 ). As a result, the device driver supplies power from the power supply unit  360  to the printer unit  130 . That is, power is supplied to the fixing unit of the printer unit  130  (ACT  210 ). In the process of  FIG. 6 , it is assumed that the wake-up of the printer unit  130  before the system wake-up is set to be valid in ACT  208 . 
     The device driver sets the B-Power port to ON and then gives a wake-up instruction to each of the functions (ACT  211 ). Specifically, first, the device driver starts power supply from the power supply unit  360  to the image reading device  200 , the auxiliary storage device  320 , and the CPU  340 . Next, the device driver wakes up the OS and wakes up various HW such as ASIC or the auxiliary storage device  320 . As a result, the CPU  340  shifts the mode of the apparatus from the Super-Sleep mode to the normal mode. Next, the printer unit  130  prints print data. 
     With the power supply control system  10  having the above-described configuration, the time until printing can be reduced when compared to the related art. Specifically, only when a specific event occurs, the image forming apparatus  100  sets the timing of power supply to the fixing unit of the printer unit  130  before the system wake-up. As a result, power is supplied to the fixing unit of the printer unit  130  even while the system is waking up. Accordingly, a lamp included in the fixing unit can be rapidly heated. Therefore, the time until printing can be reduced. 
     More specifically, in the image forming apparatus  100 , the microcomputer  350  determines the specific character string included in the packet. When the predetermined character string matches with the specific character string included in the packet, the image forming apparatus  100  restarts power supply to the printer unit  130  before the system wake-up. Accordingly, it is not necessary to analyze detailed data in the packet unlike the related art. Therefore, the type of the packet can be discriminated with a simple method. 
     Hereinafter, a modification example of the power supply control system  10  will be described. 
     The microcomputer  350  may be incorporated into the network interface  310 . 
     The printer driver of the information processing apparatus  50  may generate the packet by setting a character string indicating the wake-up of the printer unit  130  instead of or in addition to the print character string. In this configuration, when the packet includes the character string indicating the wake-up of the printer unit  130 , the microcomputer  350  performs the power supply control on the printer unit  130 . 
     The printer driver of the information processing apparatus  50  may generate the packet by setting a character string indicating a user name instead of or in addition to the print character string. In this configuration, the microcomputer  350  compares the character string of the specific portion to the pre-stored character string and, when the character strings match with each other, gives the notification to the device driver. At this time, the notification output from the microcomputer  350  includes the character string described in the packet. The device driver extracts the character string indicating the user name from the character string included in the notification output from the microcomputer  350 . Next, the device driver compares the extracted character string to a character string described in a list in which a pre-stored character string indicating a user name is described. When the extracted character string matches with the character string described in the list, the device driver supplies power from the power supply unit  360  to the printer unit  130 . 
     The image forming apparatus  100  according to at least one of the above-described embodiments includes the printer unit  130 , the CPU  340 , the power supply unit  360 , and the microcomputer  350 . The printer unit  130  forms an image on a sheet. The CPU  340  performs a control of shifting a state of the apparatus from a normal mode to a power saving mode. The power supply unit  360  supplies power to the CPU  340  and the printer unit  130  in the normal mode and supplies power to the CPU  340  and stops power supply to the printer unit  130  in the power saving mode. When the print character string is described in the packet received in the power saving mode, the microcomputer  350  performs the power supply control on the printer unit  130  before performing the power saving mode on the CPU  340 . As a result, the time until printing can be reduced. 
     Some functions of the image forming apparatus  100  in the embodiment may be realized by a computer. In this case, a program for realizing this function is recorded in a computer-readable recording medium. The function may be realized by causing a computer system to read the program recorded in the recording medium and to execute the read program. The definition of “computer system” described herein includes an operating system and a hardware such as a peripheral. The definition of “computer-readable recording medium” includes a portable medium and a storage device. The portable medium is, for example, a flexible disk, a magneto-optic disk, a ROM, or a CD-ROM. The storage device is, for example, a hard disk built into a computer system. The “computer-readable recording medium” dynamically stores a program for a short period of time such as a communication line while a program is being transmitted through a communication line. The communication line is, for example, a network such as the Internet or a telephone line. The “computer-readable recording medium” may be a volatile memory in a computer system that functions as a server or a client. The volatile memory stores a program for a certain period of time. The program may realize a part of the above-described function. The program may realize the above-described function in combination of a program that is recorded in advance in a computer system. 
     While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.