JP5335469B2 - Image forming apparatus and control method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus of which the time required for a starting process when a main power source is started and a returning process when returning from a sleep mode are shortened increasing neither the cost nor the size of the apparatus, and to provide a control method for the image forming apparatus. <P>SOLUTION: In the image forming apparatus, a controlling controller section measures the passage of time up to receiving of a communication command from an image processing controller section when the main power source is started. The controlling controller section executes the starting process of an image processing section independently prior to reception of the communication command when the communication command is not received before the passage of time exceeds the first prescribed time. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, and a facsimile machine, and a startup control method thereof.

  2. Description of the Related Art Image forming apparatuses such as printers and scanners are known that have a power saving mode (sleep mode) function for stopping functions other than some functions of the image forming apparatus for the purpose of power saving. . In such an image forming apparatus, when returning from the sleep mode to an activated state capable of executing the functions of the apparatus, it is required to reduce the time required for the return and reduce the waiting time of the user.

  In response to this request, for example, Patent Document 1 proposes a method of transmitting a sleep mode release request signal to a printer via a communication device and a signal transmission line when performing display processing of a print dialog on a display device. ing. The printer starts the sleep mode cancellation process in response to the signal, thereby reducing the time required for returning from the sleep mode.

  The problem of shortening the startup time from the stop state in the image forming apparatus as described above is not only when returning from the sleep mode, but also when starting the main power supply in the image forming apparatus in which the supply of the main power supply is stopped. This is a common issue.

  In the following, with reference to FIG. 9, a problem in the case of starting the main power supply of the image forming apparatus will be described. FIG. 9 is a timing chart showing the operation timing when the main power supply in the conventional image forming apparatus is started. In FIG. 9, in order from the top, main power state 901, image processing controller unit power state 902, image processing controller unit CPU reset release state 903, image processing controller unit CPU activation state 904, image processing A communication state 905 between the CPU of the controller unit and the CPU of the control controller unit is shown. Further, a power supply state 906 of the control controller unit, a reset release state 907 in the CPU of the control controller unit, a startup state 908 of the CPU of the control controller unit, and an engine unit state 909 are shown.

  First, with the activation of the main power supply of the image forming apparatus, power is turned on to the image processing controller unit and the control controller unit.

  Next, in each CPU, a boot program is executed after the set reset release time. Here, there is a large difference in processing time between the CPU of the image processing controller unit and the CPU of the control controller unit according to the Boot program for developing the Main program. This is because the size of the Main program mounted on both CPUs is greatly different. Usually, the image processing controller unit has a larger main program size than the control controller unit, and therefore the development time is longer.

  The CPU of the control controller unit that has completed the development of the Main program first and has shifted to an activated state capable of executing the Main program waits until it receives a communication command 910 transmitted from the CPU of the image processing controller unit.

  On the other hand, when the boot of the boot program is finished and the CPU of the image processing controller unit shifts to a start state in which the main program can be executed, the CPU of the control controller unit becomes ready for communication. Then, the CPU of the image processing controller unit transmits a communication command 910 to the CPU of the control controller unit. The CPU of the control controller unit that has received the communication command 910 performs an initialization operation that is a starting process of an image forming unit (cartridge, transfer belt, fixing device, etc.) that is an engine unit, based on the command content.

JP 2003-29954 A

  However, in the above-described conventional technology, due to the size of the program in the image processing controller unit, the time until the communication between both controller units is established increases. The control controller unit waits until a communication command is received from the image processing controller unit, and starts an initialization operation of the image forming unit based on the communication command. As a result, there is a problem that the time until the image forming unit is activated by the control controller unit increases.

  Further, when the image forming unit is initialized in the control controller unit, it is possible to reduce the waiting time of the user by determining whether to return from the sleep mode or to start from the main power supply stop state. On the other hand, when a dedicated signal line for separation is provided, there are problems such as an increase in cost due to an increase in interfaces and an increase in board size and connector size.

  The present invention has been made in view of the above-described problems, and does not cause an increase in cost or an increase in the size of the apparatus. An object of the present invention is to provide an image forming apparatus and a control method therefor that reduce the time required for the return processing.

The present invention can be realized as an image forming apparatus, for example. The image forming apparatus includes a plurality of devices, a stopped state in which the main power supply is stopped, a startup state in which power is supplied from the main power source to the plurality of devices, and a part of the plurality of devices from the main power source. An image forming apparatus that is supplied with electric power and has a power saving state that consumes less power than an activated state, the image forming unit forming an image on a recording material, and an image forming unit among a plurality of devices When the image forming apparatus is activated from a stopped state or a power saving state, when the activation of the first control unit is completed, a predetermined communication command is issued. First control means for outputting and second control means for controlling the image forming unit and executing the image forming unit activation process when the image forming apparatus is activated from the stopped state or the power saving state. , Comprising a second control means, start the second control means by which power is supplied, the predetermined communication command without power supply to the second control means stops the A time measuring means for measuring an elapsed time until reception from one control means, and a predetermined communication command is sent from the first control means before the elapsed time measured by the time measuring means reaches the first predetermined time. If received, starts the startup processing of the image forming unit in response to reception of a predetermined communication command, the elapsed time without receiving a predetermined communication command from the first control means reaches a first predetermined time In this case, the start processing of the image forming unit is started when the first predetermined time is reached.

The present invention can be realized, for example, as a method for controlling an image forming apparatus. The control method includes a stop state in which the main power supply is stopped, a startup state in which power is supplied from the main power supply to a plurality of devices, and power is supplied from the main power supply to some of the plurality of devices. An image forming apparatus that selectively shifts to each state of a power saving state that consumes less power than an activated state, and further includes an image forming unit that forms an image on a recording material, and an image forming unit among a plurality of devices. A first control unit that controls devices other than the included devices, and an image forming unit that controls the image forming unit, and executes an activation process of the image forming unit when the image forming apparatus is activated from a stopped state or a power saving state. When the image forming apparatus is activated from a stopped state or a power saving state, the first control means performs predetermined communication when its activation is completed. An output step of outputting a command, the second control means, after starting the second control means by which power is supplied, a predetermined without power supply to the second control means is stopped A step of counting an elapsed time until the communication command is received from the first control means; and a second control means before the elapsed time reaches the first predetermined time. and initiating a boot process of the image forming unit in response to receiving a predetermined communication command from the second control means, the elapsed time without receiving a predetermined communication command from the first control means first And a step of starting activation processing of the image forming unit in response to reaching a predetermined time of 1.

  According to the present invention, for example, an image that shortens the time required for the start-up process when starting from the main power stop state and the return process when returning from the sleep mode without increasing the cost or enlarging the apparatus. A forming apparatus and a control method thereof can be provided.

1 is a diagram illustrating a configuration example of an image forming apparatus according to an embodiment of the present invention. 5 is a flowchart illustrating a processing procedure of the image forming apparatus according to the embodiment of the present invention. It is a timing chart which shows the operation timing in the case of starting the main power supply concerning the embodiment of the present invention. It is a timing chart which shows the operation timing when abnormality arises in the image processing controller part when starting the main power supply concerning the embodiment of the present invention. FIG. 3 is a diagram illustrating a state of each device in a sleep mode state of the image forming apparatus according to the embodiment of the present invention. It is a timing chart which shows the operation timing in the case of returning from sleep mode concerning the embodiment of the present invention. It is a figure which shows the structural example of the circuit for detecting opening and closing of a door in the sleep mode state which concerns on embodiment of this invention. It is a timing chart which shows the operation timing of the circuit for detecting opening and closing of a door in the sleep mode state concerning the embodiment of the present invention. It is a timing chart which shows the operation timing in the case of starting the conventional main power supply.

  An embodiment of the present invention is shown below. The embodiments described below will help to understand various concepts such as the superordinate concept, intermediate concept and subordinate concept of the present invention. Further, the technical scope of the present invention is determined by the scope of the claims, and is not limited by the following embodiments.

<Overall configuration of image forming apparatus>
Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 8. FIG. 1 is a diagram illustrating an example of a block configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 5 is a diagram illustrating the state of each device in the image forming apparatus in the power saving mode (sleep mode). In FIG. 5, the power supply start / stop (ON / OFF) state in each device is shown. The image forming apparatus includes two controller units, a control controller unit 100 and an image processing controller unit 150.

  The control controller unit 100 controls an image forming unit (engine unit) that performs image forming processing on a recording material, such as a paper transport unit, a fixing device, a cartridge, a transfer belt, a high-pressure unit 113, and a laser unit 117.

  A CPU 101 is a CPU that performs image formation control, and sequentially reads and executes a program from a read-only memory (hereinafter referred to as ROM) 103 that stores a control procedure (control program) of the apparatus main body. The CPU 101 and each load are connected by an address bus and a data bus.

  A random access memory (hereinafter referred to as RAM) 104 is used as a storage for input data, a working storage area, or the like. The nonvolatile RAM 120 is used as a storage area for parameters relating to image forming operations.

  The I / O interface 106 is connected to loads such as motors 107, clutches 108, solenoids 109, paper detection sensors 110, toner sensors 111, switches 112, a high voltage unit 113, and a heater 116. The motors 107 drive the paper feed system, the transport system, and the optical system. The paper detection sensors 110 detect the conveyed paper. The toner sensor 111 detects the remaining amount of toner in a developing device (not shown). The switches 112 detect the home position and the like of each load. The high voltage unit 113 outputs a high voltage to a primary charger, a developing device, a pre-transfer charger, a transfer charger, and a separation charger (not shown) according to instructions from the CPU. The heater 116 is formed of a ceramic substrate or the like, and an AC voltage is supplied by an on / off signal.

  In the controller 100 described above, when the image forming apparatus is in the sleep mode, as shown in FIG. 5, the power of all devices is stopped in the same manner as the supply of power from the main power supply is stopped. It becomes. Note that the shaded portion has stopped functioning.

  Next, the image processing controller unit 150 will be described. The image processing controller unit 150 performs image processing on image signals from the reading processing unit 170 and externally connected devices such as a PC, and creates data to be written in the laser unit 117. The image processing controller unit 150 can also store image data that has undergone image processing on an externally connected device such as a PC or a storage medium such as a USB memory connected to the operation unit 181.

  The CPU 151 mounted on the image processing controller unit 150 sequentially reads and executes the program from the ROM 153 storing the image processing control procedure (image processing control program). The RAM 154 is a main storage device used as a storage area for input data, a work storage area, or the like.

  The recording processing IC 157 performs image processing on image signals from the reading processing unit 170 and externally connected devices such as a PC, and generates PWM data to be written in the laser unit 117. Further, the recording processing IC 157 performs control to turn on the laser mounted on the laser unit 117 according to the image data via the image signal line. Laser light output from the laser unit 117 irradiates and exposes a photosensitive drum (not shown). The laser light is detected in the non-image area by the BD sensor 114 as a light receiving sensor, and an output signal (BD signal) is input to the scanner control IC 121. The scanner control IC 121 controls rotation of a polygon motor (not shown) mounted on the laser unit 117 and outputs an image synchronization signal to the image processing controller unit 150 using the BD signal.

  The nonvolatile RAM 161 is used as a storage area for parameters related to image processing.

  The I / O interface 156 is mounted on the reading processing unit 170, and is connected to motors 173, solenoids 174, sensors 175, and the like.

  The reading processing IC 160 performs processing of image data from the reading sensor 172 mounted on the reading processing unit 170 and driving of the reading sensor 172 via the reading control IC 171.

  The image processing RAM 159 is used as a storage area for temporarily storing data when image processing is performed on data received by the reading processing IC 160 or data from an externally connected device such as a PC.

  The LAN controller 158 controls communication with an external connection device such as a PC connected via a LAN cable.

  The CPU 151 controls the operation unit 181 that is a user interface for the user to operate the image forming apparatus, the NCU 185 that controls the FAX, and the door sensors 191 that detect the open / closed state of the door (door) of the image forming apparatus. Is also going.

  In the image processing controller 150 described above, as shown in FIG. 5, when the image forming apparatus is in the sleep mode, only the LAN controller 158, some switches of the operation unit 181, the door sensors 191, and the RAM 154 are included. Power is on. As described above, in the image forming apparatus in the sleep mode, only some functions are in the power saving state in the activated state, and other functions are in the stopped state.

  At this time, the RAM 154 is in a self-refresh mode and operates in a low power mode that holds only current data. The image forming apparatus in the sleep mode can release the sleep mode and start the return processing from the sleep mode by receiving a communication command from the LAN cable or a signal from the switch of the operation unit 181. is there.

  The CPU 101 and the CPU 151 are connected to each other by asynchronous communication or clock synchronous serial communication via a communication line. Through the communication between the CPU 101 and the CPU 151, the timing of outputting image data to the image forming unit of the image forming apparatus, the start and end of the image forming apparatus, and the transition control to the sleep mode are performed.

  In addition, the CPU 151 transmits a communication command to the CPU 101 during the startup process after the main power supply is stopped and the return process from the sleep mode. This command notifies whether the image forming apparatus has been started from the stop state or the power saving state. The CPU 101 performs activation control of the image forming unit based on the communication command. The CPU 151 corresponds to the first control unit, and the CPU 101 corresponds to the second control unit.

<Procedure for Starting Processing of Image Forming Apparatus>
FIG. 2 is a flowchart showing the procedure of the startup process by the CPU 101 according to the embodiment of the present invention. Note that the image forming apparatus is in a state in which the supply of power from the main power supply is stopped or in the sleep mode.

  The control controller unit 100 and the image processing controller unit 150 are activated when the main power source of the image forming apparatus is activated or when the return processing from the sleep mode is started. Here, the CPU 101 completes activation before the CPU 151. This is because the size of the program to be activated in the CPU 101 is smaller than the size of the program to be activated in the CPU 151. Further, the return time of the CPU 151 when returning from the power saving state is shorter than the return time of the CPU 151 when the image forming apparatus returns from the stopped state. The reason for this is as follows. During the power saving state, the RAM 154 is in the self-refresh mode, and the program of the CPU 151 is held in an expanded state, so that the recovery time is short. On the other hand, when returning from the stopped state, the program compressed by the ROM 153 is decompressed and expanded on the RAM 154 and then the CPU 151 starts to start the program.

  When activated, the CPU 101 starts a counter for measuring the elapsed time until the communication command transmitted from the CPU 151 is received in step S201. Note that the measurement of the elapsed time by the counter corresponds to the processing by the time measuring means. The CPU 101 also has a function as a time measuring means. In step S202, the CPU 101 stands by until a communication command transmitted from the CPU 151 is received.

  Here, when the CPU 101 receives the communication command before the count value of the counter reaches the first predetermined time, the CPU 101 determines to return from the sleep mode, and proceeds to step S203. In step S203 and subsequent steps, a return process from the sleep mode (hereinafter referred to as “sleep return process”) is executed. Note that the first predetermined time will be described later with reference to FIGS. 3 and 4.

  On the other hand, if the communication command is not received in step S208 and the count value of the counter reaches the first predetermined time, the CPU 101 determines that the main power supply of the image forming apparatus has been activated, and proceeds to step S209. In step S209 and subsequent steps, a start-up process (hereinafter referred to as “power-on process”) from a state where the main power supply is stopped is executed.

  The above determination processing corresponds to the processing by the first determination unit that determines whether or not the elapsed time based on the counter has exceeded the first predetermined time. The CPU 101 also has a function of first determination means. The counter is cleared when a communication command is received.

(Sleep recovery process procedure)
In step S203, the CPU 101 determines whether opening / closing of the door of the image forming apparatus is detected. If the opening / closing of the door is detected, the process proceeds to a first sleep return process in step S204, and if not detected, the process proceeds to a second sleep return process in step S206. In the first sleep return processing, initialization (initialization) operations of the cartridge, the transfer belt, the fixing device, and the like are performed. This is because, when opening / closing of the door is detected, replacement of the cartridge, the transfer belt, the fixing device, and the like is assumed. On the other hand, in the second sleep recovery process, only the operation of applying the nip pressure of the fixing device is performed. This is because when the opening / closing of the door is not detected, it is assumed that the image forming apparatus holds the state before transition to the sleep mode. For this reason, the second sleep recovery process has a shorter processing time than the first sleep recovery process.

  In step S <b> 205, the CPU 101 determines whether or not the first sleep recovery process has been completed. When the first sleep recovery process is completed, the image forming apparatus shifts to a standby state. Similarly, in step S207, the CPU 101 determines whether or not the second sleep recovery process is completed, and ends the process when completed. When the second sleep recovery process is completed, the image forming apparatus shifts to a standby state. The first sleep return process and the second sleep return process described above correspond to the first return process and the second return process executed by the activation control unit. The CPU 101 also corresponds to a start control unit that executes the first return process and the second return process.

(Power ON procedure)
In step S209, the CPU 101 starts an initialization operation of the cartridge, the transfer belt, the fixing device, and the like as a power ON process. At the same time, the CPU 101 stands by until a communication command is received from the CPU 151 in step S210. At this time, if the CPU 101 receives a communication command before the activated counter reaches a second predetermined time longer than the first predetermined time, the CPU 101 continues the power ON process. Note that the second predetermined time will be described later with reference to FIGS. 3 and 4. In step S <b> 211, the CPU 105 determines whether or not the power ON process has been completed, and ends the process when completed. Thereafter, the image forming apparatus shifts to a standby state.

  On the other hand, in step S212, when the CPU 101 does not receive the communication command and the counter reaches the second predetermined time, the CPU 101 determines that an abnormality has occurred in the image processing controller unit 150, and stops the power ON process.

  The above processing corresponds to the processing by the activation control means. Further, the comparison process between the counter and the second predetermined time in steps S210 and S212 corresponds to the determination process by the second determination unit.

<Timing chart when starting from the main power stop state>
3 and 4 are timing charts showing the operation timing when the main power supply is activated in the image forming apparatus according to the embodiment of the present invention. FIG. 3 shows a case where the image processing controller unit 150 is normally activated. FIG. 4 shows a case where an abnormality has occurred in the image processing controller unit 150.

3, in order from the top, the main power state 301 of the image forming apparatus, the power state 30 2 of the image processing controller 150, the reset release state 30 3 of the CPU 151, the startup state 30 4 of the CPU 151, the CPU 151 and the CPU 101, communication state 30 5 is shown. Furthermore, a power supply state 306 of the control controller unit 100, a reset release state 307 of the CPU 101, a startup state 308 of the CPU 101, a startup counter state 309, an engine unit state 310, and an error counter state 311 are shown. Also, 401 to 411 in FIG. 4 correspond to 301 to 311 in FIG.

  As shown in FIGS. 3 and 4, first, the image processing controller unit 150 and the control controller unit 100 are powered on as the main power source of the image forming apparatus is activated.

  Next, the CPU 151 and the CPU 101 execute a boot program after a reset release time set for each. Note that the Boot program is a program for developing a Main program necessary for the operation of the CPUs 101 and 151 and making it executable. Here, there is a great difference in the processing time of the Boot program between the CPU 151 and the CPU 101. This is because the size of the Main program mounted on both CPUs is greatly different. Normally, the main program of the image processing controller unit 150 is larger in size than the main program of the control controller unit 100, so that the development time becomes longer. In general, only the program necessary for developing the Main program is implemented as a Boot program.

  The development of the Main program is completed first, and the CPU 101 that has shifted to the activated state waits until a communication command transmitted from the CPU 151 is received. When the control controller unit 100 shifts to the activated state, the CPU 101 activates a counter for measuring the elapsed time from the time when the transition to the activated state is completed. The counter is used for determining the activation state of the CPU 151 and determining whether an abnormality (error) has occurred in the image processing controller unit 150. In the following, for convenience of explanation, a case where separate counters such as a start counter and an error counter are used for both determinations is shown, but only one counter may be used as shown in FIG.

  When the CPU 101 does not receive the communication command and the activation counter reaches the first predetermined time, the CPU 101 determines that the activation process is performed when the main power source is activated. The determination is based on the fact that there is a difference in the timing at which the communication command is received by the CPU 101 between when returning from the sleep mode and when the main power supply is activated, and that each timing is substantially constant. .

  Here, in the startup process when the main power supply is started, the time required for developing the Main program in the image processing controller unit 150 is substantially constant. This is because the required time is defined by the size of the program. For the same reason, when returning from the sleep mode, the time required to make the Main program executable is substantially constant. Further, the time required for returning from the sleep mode is shorter than the time required for starting the main power supply. Therefore, the first predetermined time is set between the reception timing in the return processing from the sleep mode and the reception timing in the startup processing when starting the main power supply. Thus, when the CPU 101 does not receive the communication command and the first predetermined time has elapsed, the CPU 151 determines that the startup process for starting the main power supply is performed instead of the return process from the sleep mode. Is possible.

  If the CPU 101 determines that the main power supply is activated, the CPU 101 executes the above-described power-on process prior to receiving the communication command from the CPU 151.

  When the main program is activated in the CPU 151 after the power-on process by the CPU 101 is started, the CPU 151 and the CPU 101 can communicate with each other. Then, the CPU 151 transmits a communication command 312 to the CPU 101 as shown in FIG. The CPU 101 that has received the communication command 312 determines that the image processing controller unit 150 is normal, and continues the power ON process of the image forming unit.

  On the other hand, as illustrated in FIG. 4, the CPU 101 determines that an abnormality has occurred in the image processing controller unit 150 when the communication command is not received at a timing that should be received and the counter reaches the second predetermined time. This is because a communication command cannot be transmitted to the CPU 101 when the CPU 151 cannot start the Main program for some reason. In this case, the CPU 101 clears the error counter in the second predetermined time, and stops the power ON process of the image forming unit.

  The second predetermined time is set based on the timing at which the CPU 101 receives the communication command 312 from the CPU 151 when the main power supply is activated. As described above, the time required for development of the Main program in the CPU 151 is substantially constant due to the size of the program. For this reason, when the CPU 151 normally shifts to the activated state, the CPU 101 receives the communication command 312 at substantially constant timing. Therefore, if the second predetermined time is set to a time exceeding the reception timing, the CPU 101 can determine an abnormality in the CPU 151 based on whether or not a communication command is received.

  The first predetermined time and the second predetermined time can be set in advance based on the version of the Main program.

<Timing chart when returning from sleep mode>
FIG. 6 is a timing chart showing the operation timing when the image forming apparatus according to the embodiment of the present invention returns from the sleep mode. Note that reference numerals 601 to 611 in FIG. 6 correspond to 301 to 311 in FIG. 3.

  First, as the image forming apparatus starts the return processing from the sleep mode, the CPU 151 and the CPU 101 are powered on.

  Next, the CPU 101 and the CPU 151 execute the boot program after the reset release time set for each.

  During the sleep mode, the RAM 154 of the image processing controller unit 150 is in the self-refresh mode and holds data. Therefore, the CPU 151 can start the Main program immediately. After starting, the CPU 151 transmits a communication command 612 to the CPU 101. The communication command 612 includes information indicating the open / closed state of the door of the image forming apparatus. A method of detecting the door open / close state during the sleep mode will be described later.

  The CPU 101 that has received the communication command 612 clears the activation counter and the error counter, and performs the above-described first sleep return process or second sleep return process according to the command.

<Detection of door opening / closing in image forming apparatus in sleep mode>
FIG. 7 is a diagram illustrating a circuit for detecting opening / closing of the door of the image forming apparatus during the sleep mode. FIG. 8 is a timing chart showing circuit operation timing for detecting door opening / closing of the image forming apparatus during the sleep mode.

  As shown in FIG. 7, a circuit for detecting opening and closing of a door is configured using a DK flip-flop, and is mounted on an image processing board. The DR_SNS_IN signal is an input signal of a door detection sensor that detects opening and closing of the door of the image forming apparatus. A signal indicating ‘H’ is output when the door is closed, and ‘L’ is output when the door is open. As a power source for this circuit, a 3.3V power source that is ON even during the sleep mode is used. The DRSNS_SET signal is a control signal for operating this circuit, and the DR_SNS_OUT signal is a signal for detecting whether the door of the image forming apparatus has been opened or closed.

  As shown in FIG. 8, by setting the DRSNS_SET signal 801 to ‘L’, the DK flip-flop is preset, and the DR_SNS_OUT signal 804 becomes ‘H’. Note that the initial value of the DR_SNS_OUT signal 804 is ‘L’, but it may be ‘H’ or ‘L’.

  Next, when the DRSNS_SET signal 801 is set to “H”, a circuit for detecting door opening / closing is activated. As shown in the state 803 of the door of the image forming apparatus, when the door is opened in this state, the DR_SNS_IN signal 802 changes from 'H' to 'L'. Therefore, since a signal is input to CLK of the DK flip-flop, the DR_SNS_OUT signal 804 outputs ‘L’ and holds ‘L’. In order to set this output to ‘H’, it is necessary to set the DRSNS_SET signal 801 to ‘H’. Therefore, it is possible to detect whether or not the door opening / closing operation has been performed during the sleep mode.

  Note that the circuit of FIG. 7 is an example of a latch circuit, but other circuits may be used in the present invention.

  As described above, when the main power supply is activated, the image forming apparatus according to the present embodiment measures the elapsed time until the communication command is received from the image processing controller unit in the control controller unit. When the communication controller is not received before the elapsed time exceeds the first predetermined time, the control controller unit independently starts the activation processing of the image processing unit prior to reception of the communication command. As a result, the control controller unit can start its own startup process without waiting for the completion of the startup process of the image processing controller unit, so that the time required for the startup process can be shortened.

  Further, since the control controller unit can uniquely determine the activation state of the image processing controller unit, the image processing controller unit can return to the control controller unit from the sleep mode or the main power supply can be activated. There is no need to provide a dedicated line for notifying whether or not there is. As a result, it is possible to avoid an increase in cost due to an increase in interfaces and an increase in board size and connector size.

  Furthermore, the image forming apparatus according to the present embodiment detects the opening / closing of the door of the image forming apparatus in the sleep mode, and based on the result, the control controller unit changes the sleep return process to return from the sleep mode. Can be shortened.

100: Control controller unit 150: Image processing controller unit 101, 151: CPU
103, 153: ROM
104, 154: RAM
106, 156: I / O interface 117: Laser unit 121: Scanner control IC
157: Recording processing IC
158: LAN controller 159: Image processing RAM
160: Reading processing IC
170: Reading processing unit 181: Operation unit 185: NCU
191: Door sensors

Claims (8)

A plurality of devices, a stopped state in which a main power supply is stopped; a startup state in which power is supplied from the main power supply to the plurality of devices; and power from the main power supply to some of the plurality of devices. And an image forming apparatus having a power saving state with less power consumption than the activated state,
An image forming unit for forming an image on a recording material;
Of the plurality of devices, a first control unit that controls devices other than devices included in the image forming unit, wherein the image forming apparatus is activated from the stopped state or the power saving state. The first control means for outputting a predetermined communication command upon completion of activation of the first control means;
A second control unit that controls the image forming unit, and executes a startup process of the image forming unit when the image forming apparatus starts up from the stopped state or the power saving state.
The second control means includes
The predetermined communication command is received from the first control means without stopping the supply of power to the second control means after the second control means is activated by supplying power. Equipped with a time measuring means to measure the elapsed time until
When the predetermined communication command is received from the first control means before the elapsed time counted by the time measuring means reaches the first predetermined time, the reception of the predetermined communication command is performed. When the elapsed time reaches the first predetermined time without receiving the predetermined communication command from the first control unit, the image forming unit start process is started. An image forming apparatus, wherein start-up processing of the image forming unit is started in response to reaching time. The first predetermined time is
The image formation is longer than the time required for the second control means to receive the predetermined communication command from the first control means after the image forming apparatus starts to start from the power saving state. The time is determined to be shorter than the time required for the second control means to receive the predetermined communication command from the first control means after the apparatus starts activation from the stopped state. The image forming apparatus according to claim 1.   The time required from the start of the image forming apparatus starting from the stopped state to the completion of the starting of the first control unit is longer than the time required for the image forming apparatus to start from the stopped state. The image forming apparatus according to claim 1, wherein the time when the forming apparatus starts from the power saving state is shorter. The image forming apparatus further comprises detection means for detecting opening and closing of the door,
The second control means includes
When starting the image forming unit at the reception timing of the predetermined communication command, if the opening / closing of the door is detected by the detection means before the reception timing, the first processing is performed as the start processing. If the opening / closing of the door is not detected by the detection means before the reception timing, a second return process having a shorter processing time than the first return process is performed as the start-up process. The image forming apparatus according to claim 1, wherein: The second control means includes
After the start processing of the image forming unit is started in response to reaching the first predetermined time, before the elapsed time reaches a second predetermined time longer than the first predetermined time, When the predetermined communication command is received from the first control means, the image forming unit activation process is continued,
After starting the image forming unit activation process in response to reaching the first predetermined time, the elapsed time does not receive the predetermined communication command from the first control unit. 5. The image forming apparatus according to claim 1, wherein when the predetermined time is reached, start-up processing of the image forming unit is stopped. 6. The second predetermined time is a time required for the second control unit to receive the predetermined communication command from the first control unit after the image forming apparatus starts to start from the stopped state. The image forming apparatus according to claim 5, wherein the image forming apparatus is set to a longer time. The first control unit and the second control unit include an image signal line for the first control unit to output image data to the second control unit, and the first control unit 7. The image forming apparatus according to claim 1, wherein the image forming apparatus is connected to a second control unit by a communication line for outputting the predetermined communication command. A stopped state in which the main power supply is stopped, a start-up state in which power is supplied from the main power supply to a plurality of devices, power is supplied from the main power supply to some devices of the plurality of devices, An image forming apparatus that selectively shifts to a power saving state that consumes less power than a startup state, and
An image forming unit for forming an image on a recording material;
A first control means for controlling a device other than the devices included in the image forming unit among the plurality of devices;
An image forming apparatus comprising: a second control unit that controls the image forming unit and that executes a start process of the image forming unit when the image forming apparatus starts up from the stopped state or the power saving state. In the control method of
When the image forming apparatus is activated from the stopped state or the power saving state, the first control unit outputs a predetermined communication command when the activation of the first control unit is completed;
Wherein said second control means, after starting said second control means by which power is supplied, the predetermined communication command without the supply of power to the second control means is stopped Measuring the elapsed time until reception from the first control means ;
The second control unit receives the predetermined communication command from the first control unit before the measured elapsed time reaches the first predetermined time. A step for starting the boot process;
The second control unit performs the activation processing of the image forming unit in response to the elapsed time reaching the first predetermined time without receiving the predetermined communication command from the first control unit. The steps to begin,
A control method for an image forming apparatus.

Images