JP2014115922A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of further reducing power consumption.SOLUTION: In an active mode (step S10:YES), when there is no occurrence of an event or execution of a task being a condition for shifting from a sleep mode to the active mode (step S12:YES), the duration time is counted by a counter T (step S14). The counter T shows a threshold for light sleep Tth1 or more (step S18:YES), and thereby, a mode is shifted to the light sleep mode (step S20). The threshold for light sleep Tth1 varies in accordance with the type of an event which is a trigger for shifting from the sleep mode to the active mode.

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus that can further reduce power consumption.

  For example, Patent Document 1 below discloses an MFP (Multi Function Peripheral) having various functions such as copying, facsimile, scanner, and printer. It also describes that a function of shifting to an energy saving mode for reducing the total power supply amount of the device is provided in order to reduce the power consumption of the MFP. In this apparatus, in the normal mode, for example, when an occurrence of an event such as a key operation or an opening / closing operation of the platen cover is detected, the apparatus shifts to a normal mode in which the total power supply amount is larger than that in the energy saving mode.

  Further, in the above device, when the transition time elapses without detecting the occurrence of an event, the transition time is shortened by shifting to the energy saving mode and satisfying the transition condition a plurality of times within a predetermined period. Has been.

JP 2010-32666 A

  In the above technique, the number of times the transition condition is established within a predetermined period is a parameter for predicting whether the user uses the MFP. However, there is a problem that the above parameters are not necessarily sufficient for predicting whether or not the user uses the MFP when returning to the energy saving mode after returning from the energy saving mode.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus that can further reduce power consumption.

  In order to achieve this object, an image forming apparatus of the present invention includes a processing unit that executes various processes, a power supply unit that supplies power to the processing unit, and a total power supply amount from the power supply unit to the processing unit. An energy saving mode to be reduced, and a power control unit that performs switching control of the normal mode in which the total power supply amount is larger than the energy saving mode, and the processing executed by the processing unit reads an original and reads an image Including at least one of a generation process for generating data and a recording process for recording an image obtained by image data on a recording medium, wherein the power control unit is a condition for shifting from the energy saving mode to the normal mode. Detection means for detecting occurrence of an event, determination means for determining whether or not it is an execution period of the at least one process by the processing unit, and the normal In the mode, the timing means for counting the duration time in which the occurrence of the event is not detected by the detection means and the status is not determined as the execution period by the determination means, and the measured duration time An energy-saving mode transition means for shifting from the normal mode to the energy-saving mode by being equal to or greater than a threshold having a finite length determined for shifting from the normal mode to the energy-saving mode; and during the energy-saving mode When an event is detected by the detection unit, a normal mode transition unit that shifts to the normal mode, a specification unit that specifies an event that has triggered the transition to the normal mode, and an event specified by the specification unit And changing means for changing the threshold according to the type.

  According to the image forming apparatus of the first aspect, it is possible to control the switching between the normal mode and the energy saving mode by including the detecting means, the determining means, the time measuring means, the energy saving mode shifting means, and the normal mode shifting means. In addition, by providing the specifying means, it is possible to appropriately predict the subsequent usage status by the user based on the event that has become the trigger for shifting to the normal mode. And by providing the change means which changes a threshold value based on this prediction, transfer to an energy saving mode can be performed more appropriately, and power consumption can be reduced further by extension.

  In the image forming apparatus according to the second aspect, attention is paid to the following points. In other words, if the event that triggered the transition to the normal mode is something other than commanding the execution of the generation process or the recording process, then various operations for performing the generation process or the recording process may be performed. On the other hand, when the generation process or the recording process is performed, the target task is completed, and therefore there is a high possibility that nothing will be performed thereafter. In view of this point, in the image forming apparatus according to claim 2, in addition to the effect of the image forming apparatus according to claim 1, the threshold value is shortened when the normal mode is entered by an execution command for generation processing or recording processing. Thus, there is an effect that the energy saving mode can make an early and appropriate transition.

  In the image forming apparatus according to claim 3, in the case of a state change in which the event that triggered the transition to the normal mode is a state change detected by the state change detection unit, the instruction information is input through the input unit. Note that it is considered unlikely that a series of processing until the user commands generation processing or recording processing is performed. Thus, in the image forming apparatus according to claim 3, the threshold value is shortened on condition that the state is changed, so that in addition to the effect of the image forming apparatus according to claim 1 or 2, the energy saving mode can There is an effect that it is possible to shift appropriately.

  5. The image forming apparatus according to claim 4, wherein an input to the input unit by the user is required afterward even if the event that has triggered the transition to the normal mode is a state change detected by the state change detection unit. In such a case, attention is paid to the possibility that the processing is continued as compared with the case where it is not. In view of this point, by setting a threshold value, the image forming apparatus according to claim 4 shifts to the energy saving mode in addition to the effect of the image forming apparatus according to any one of claims 1 to 3. There is an effect that can be performed more appropriately.

  In the image forming apparatus according to claim 5, even when execution of at least one of the processes is instructed, the user is closer to the image forming apparatus through the input unit than through the communication unit. Note that there is a high possibility that the image forming apparatus will continue to be operated because of the high probability of being present. According to the threshold value setting in view of this point, according to the image forming apparatus according to claim 5, in addition to the effect of the image forming apparatus according to any one of claims 1 to 4, early and appropriately by the energy saving mode. The effect that it can transfer is produced.

  In the image forming apparatus according to the sixth aspect, attention is paid to the following points. That is, when an event is something other than commanding execution of generation processing or recording processing, it is highly likely that various operations for performing generation processing or recording processing will be performed after that. When the recording process is performed, the target task is completed, so that there is a high possibility that nothing will be performed thereafter. In view of this point, in the image forming apparatus according to claim 6, when the input to the input unit is an instruction to execute the generation process or the recording process, the threshold value is shortened as compared with the case where the input is not. In addition to the effect of the image forming apparatus described in any one of items 1 to 5, there is an effect that the energy saving mode can make an early and appropriate transition.

  In the image forming apparatus according to claim 7, when generation processing or recording processing is performed by a communication unit receiving an external command, it is likely that nothing is performed thereafter, and the normal mode To shift to the second energy saving mode. Thus, according to the image forming apparatus of the seventh aspect, in addition to the effect of the image forming apparatus of any one of the first to sixth aspects, the shift to the second energy saving mode can be performed more quickly and appropriately. It can be carried out.

  In the image forming apparatus according to claim 8, when an error occurs, it is noted that depending on the type, it is appropriate to set the normal mode for the user to deal with the error. In view of this point, by including the prohibition unit, in addition to the effect of the image forming apparatus according to any one of claims 1 to 7, it is easy for the user to cope with an error when it occurs. There is an effect that it can be.

  In the image forming apparatus according to the ninth aspect, the light amount of the backlight does not need to be increased when the image forming apparatus is not used. Accordingly, in addition to the effect of the image forming apparatus according to any one of claims 1 to 8, there is an effect that the energy saving mode can be appropriately realized.

1 is a perspective view showing an external configuration of an MFP according to an embodiment. FIG. 2 is a block diagram illustrating a configuration of an MFP. The figure which shows sleep mode. The flowchart which shows the procedure of the transition determination process to sleep mode. The flowchart which shows the process at the time of sleep mode. The flowchart which shows the procedure of a threshold value setting process. The flowchart which shows the procedure of the threshold value setting process concerning 2nd Embodiment. The flowchart which shows the procedure of the threshold value setting process concerning 3rd Embodiment.

<First Embodiment>
Hereinafter, a first embodiment according to the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing an external configuration of a multi-function peripheral device (Multi Function Peripheral: MFP 10). The MFP 10 has various functions such as a printer function, a scanner function, and a copy function.

  The MFP 10 includes a scanner 12 at the top, and a printer 14 is provided below the scanner 12. The scanner 12 reads an image from a document set at a predetermined reading position (not shown) and generates image data that can be recorded by the printer 14.

  The printer 14 is an inkjet printer that records an image on a recording sheet. The printer 14 performs color recording using four color inks of C (cyan), M (magenta), Y (yellow), and K (black).

  An ink cartridge mounting unit 18 for mounting four ink cartridges 16 is provided on the front right side of the MFP 10, and each of the ink cartridges 16 stores inks of C, M, Y, and K colors. The ink stored in each ink cartridge 16 is supplied to a recording head (not shown) via an ink tube. The ink cartridge mounting portion 18 is provided with an opening / closing lid 20. The ink cartridge 16 can be attached and detached by opening the opening / closing lid 20.

  In addition, the printer 14 performs recording by ejecting ink from the recording head while moving the carriage on which the recording head is mounted in a direction orthogonal to the conveyance direction of the recording paper. The upper part 13 of the MFP 10 including the scanner 12 can be opened upward. By opening the upper part 13, the inside of the printer 14 is exposed, and the user can access the inside of the printer 14 for maintenance. By exposing the inside of the printer 14, the user is allowed to access the carriage. Therefore, when a jam occurs due to the contact between the recording paper and the carriage, the user can remove the recording paper and eliminate the jam.

  An opening 22 is formed in the center of the front surface of the MFP 10, and a paper feed tray is disposed inside the opening 22 (note that FIG. 1 shows a state in which the paper feed tray is removed). The recording paper sent out from the paper feed tray is sent to the back side, and after an image is recorded by the recording head, it is discharged to a paper discharge tray installed above the paper feed tray.

  An operation panel 24 is attached to the upper surface on the front side of the MFP 10. The operation panel 24 is an operation unit for operating the scanner 12 and the printer 14, and is provided with operation keys 24a and an LCD 24b. Note that a touch panel is provided on the portion where the LCD 24b is formed, and this is an input unit together with the operation keys 24a.

  FIG. 2 shows functional blocks of the MFP 10.

  As shown in the figure, in addition to the operation panel 24, the scanner 12, and the printer 14, the MFP 10 includes a central processing unit (main CPU 30, sub CPU 32), a read-only memory (ROM 34), an occasional access memory (RAM 36), a sensor. A group 38, a power supply unit 42, and a LAN interface (LAN I / F 40) are provided. These can communicate with each other via the input / output port 44.

  The main CPU 30 executes arithmetic processing related to image formation processing displayed on the LCD 24b, image reading processing by the scanner 12, image recording processing by the printer 14, and the like. On the other hand, the sub CPU 32 performs power supply control by the power supply unit 42. The ROM 34 is a storage unit that stores programs executed by the main CPU 30 and the sub CPU 32. The RAM 36 is a storage unit that sequentially stores data when the main CPU 30 and the sub CPU 32 perform arithmetic processing.

  The sensor group 38 is various sensors that detect the state of the MFP 10. Specifically, for example, an open / close sensor that detects opening / closing of the open / close lid 20, a paper feed tray sensor that detects whether a paper feed tray is set in the opening 22, or a paper feed tray is pulled out are included. On the other hand, the LAN I / F 40 is for communicating with an external computer PC 50 via a wired LAN.

  The sub CPU 32 performs a process of reducing the power consumption inside the MFP 10 according to the usage status of the MFP 10. Specifically, an energy saving mode for reducing the total amount of power supply to the processing unit that performs various processes such as the LCD 24b, the scanner 12, the printer 14, and the main CPU 30, and a normal mode (hereinafter, referred to as a power consumption total amount higher than the energy saving mode). Switching control to “active mode” may be performed. In particular, in this embodiment, as shown in FIG. 3, two sleep modes with different total power supply amounts are provided as energy saving modes.

  That is, in the light sleep mode, the power supply amount of the main CPU 30, the scanner 12, and the printer 14 is set to a value larger than zero and is set to a sleep mode state in which the power supply amount in the active mode is limited to a small amount. Reduces the amount of light in the backlight. However, in the light sleep mode, the function of the touch panel is valid so as to respond quickly to the input operation by the user.

  On the other hand, in the deep sleep mode, the power supply to the main CPU 30, the scanner 12, and the printer 14 is turned off, and the backlight of the LCD 24b is turned off. However, also in the deep sleep mode, the function of the touch panel is valid so as to respond quickly to the input operation by the user.

  Hereinafter, power control will be described in detail with reference to FIGS.

  FIG. 4 shows the procedure for determining whether to enter the sleep mode. This processing is performed by the sub CPU 32 repeatedly executing the program stored in the ROM 34, for example, at a predetermined cycle.

  In this series of processing, the sub CPU 32 first determines in step S10 whether or not it is in the active mode. If the determination in step S10 is affirmative, the sub CPU 32 determines in step S12 whether the occurrence of an event that is a condition for shifting from the sleep mode to the active mode is detected or whether it is the task execution period. Here, the event serving as the condition mainly relates to a direct access to the MFP 10 by a user and an indirect access via the PC 50. The event types are listed in the description of FIG. On the other hand, execution of a task means execution of a generation process for reading an image by the scanner 12 and generating image data, or execution of a recording process for recording an image obtained from the image data on a recording sheet by the printer 14.

  When the sub CPU 32 makes a negative determination in step S12, in step S14, the sub CPU 32 increments a counter T1 that counts the duration of the state in which the negative determination is made in step S12. Here, the start timing of the time counting operation of the counter T1 is a timing at which the state in which an affirmative determination is made in step S12 is switched to a state in which a negative determination is made. In subsequent step S16, the sub CPU 32 determines whether or not the skip flag Fs is on. Here, the skip flag Fs is a flag instructing to shift from the active mode to the deep sleep mode without going through the light sleep mode. The skip flag Fs instructs to shift from the active mode to the deep sleep mode without going through the light sleep mode when it is on, and when it is off, the skip flag Fs goes from the active mode to the deep sleep mode through the light sleep mode. Instructed to move to.

  When making a negative determination in step S16, the sub CPU 32 determines that it should first shift to the light sleep mode as usual when shifting from the active mode to the sleep mode, and then proceeds to step S18. In step S18, the sub CPU 32 determines whether or not the counter T1 is equal to or greater than the light sleep threshold Tth1. This process is for determining whether or not the condition for shifting to the light sleep mode is satisfied. When the sub CPU 32 makes an affirmative determination in step S18, the sub CPU 32 proceeds to step S20, transitions from the active mode to the light sleep mode, and resets the counter T1.

  On the other hand, if the determination in step S16 is affirmative, the sub CPU 32 determines that the transition to the deep sleep mode should be made without going through the light sleep mode when shifting from the active mode to the sleep mode. Transition. In step S22, the sub CPU 32 determines whether or not the counter T1 is equal to or greater than the deep sleep threshold Tth2. This process is for determining whether or not the condition for shifting to the deep sleep mode is satisfied. If the sub CPU 32 makes an affirmative determination in step S22, it proceeds to step S24, transitions from the active mode to the deep sleep mode, resets the counter T1, and further turns off the skip flag Fs.

  On the other hand, if the sub CPU 32 makes a positive determination in step S12, the sub CPU 32 resets the counter T1 in step S26.

  The sub CPU 32 once ends the series of processes when the processes of steps S20, S24, and S26 are completed or when a negative determination is made in step S10.

  FIG. 5 shows a procedure of processing executed in the sleep mode. This processing is performed by the sub CPU 32 repeatedly executing the program stored in the ROM 34, for example, at a predetermined cycle.

  In this series of processing, the sub CPU 32 first determines in step S30 whether the MFP 10 is in the sleep mode. If the determination in step S30 is affirmative, the sub CPU 32 determines in step S32 whether or not an event serving as a condition for shifting to the normal mode has occurred. When the sub CPU 32 makes an affirmative determination in step S32, the sub CPU 32 proceeds to step S34 and transitions from the sleep mode to the active mode.

  On the other hand, if the sub CPU 32 makes a negative determination in step S32, it determines in step S36 whether or not the MFP 10 is in the light sleep mode. If the sub CPU 32 determines that the light sleep mode is set, the sub CPU 32 increments a counter T2 for measuring the time during which the light sleep mode is continued in step S38. The start timing of the time counting operation of the counter T2 is a switching timing from a state in which an affirmative determination is made in step S32 to a state in which an affirmative determination is made in step S36. In subsequent step 40, the sub CPU 32 determines whether or not the counter T2 is equal to or greater than the deep sleep threshold Tth2. This process is for determining whether or not the transition condition from the light sleep mode to the deep sleep mode is satisfied. If the sub CPU 32 makes a positive determination in step S40, in step S42, the state of the MFP 10 is shifted from the light sleep mode to the deep sleep mode, and the counter T2 is reset.

  The sub CPU 32 once ends the series of processes when the processes of steps S34 and S42 are completed or when a negative determination is made in steps S30, S36, and S40.

  FIG. 6 shows a procedure of processing for setting the light sleep threshold Tth1 and the deep sleep threshold Tth2 according to the present embodiment. This processing is performed by the sub CPU 32 repeatedly executing the program stored in the ROM 34, for example, at a predetermined cycle.

  In this series of processing, the sub CPU 32 first determines in step S50 whether or not it is the timing when the light sleep mode or the deep sleep mode is shifted to the active mode. If the determination in step 50 is affirmative, the sub CPU 32 determines in step S52 whether or not the event that triggered the transition to the active mode is an execution command for the generation process or recording process output by the PC 50. To do. This process is for determining whether or not the user is likely to use the MFP 10 after the transition to the normal mode. That is, in the case of an execution command from the PC 50, there is a high possibility that the user is not in a position where the user can touch the MFP 10. For this reason, there is a high possibility that an input operation to the MFP 10 via the operation panel 24 is not performed after the generation process or the recording process corresponding to the execution command is completed.

  When making a positive determination in step S52, the sub CPU 32 turns on the skip flag Fs in step S54, and proceeds to step S56. In step S56, the sub CPU 32 sets the light sleep threshold Tth1 and the deep sleep threshold Tth2 to “5 s”, which is the shortest time in the present embodiment. This is because it is considered that the transition to the sleep mode at an early stage after the completion of the generation process and the recording process is effective in reducing the power consumption without causing a decrease in the operability of the MFP 10. It is a thing. In other words, after the generation process and the recording process are completed, when no event occurs for “5 s”, the MFP 10 is placed in the sleep mode, and a situation that causes a decrease in user operability immediately occurs. It can be predicted that there will be no. Incidentally, when the sub CPU 32 makes an affirmative determination in step S52, the sub CPU 32 turns on the skip flag Fs in step S54, so there is no meaning in setting the light sleep threshold Tth1 in step S56. This is meaningful when the process proceeds to step S56 due to another determination result.

  If the sub CPU 32 makes a negative determination in step S52, the sub CPU 32 proceeds to step S58. In step S <b> 58, the sub CPU 32 determines whether or not an execution key for instructing execution of the generation process or the recording process is turned on on the operation panel 24 of the MFP 10. This process is for determining whether or not the user is likely to use the MFP 10 after shifting to the normal mode. That is, when the execution key is turned on, processing desired by the user is performed, so that the purpose of the user using the MFP 10 is achieved. For this reason, after the generation process and the recording process corresponding to the operation of the execution key are completed, the operation panel 24 is again set in the MFP 10 as compared with the case where the operation panel 24 is operated for recording settings such as the recording resolution and the number of recordings. There is a high possibility that no input operation will be performed.

  If the sub CPU 32 makes a positive determination in step S58, the sub CPU 32 proceeds to step S56. In contrast, if the sub CPU 32 makes a negative determination in step S58, the sub CPU 32 proceeds to step S60. In step S60, the sub CPU 32 receives an input signal indicating that a change in state of the MFP 10 has been detected in addition to the operation of the operation panel 24 from the sensor group 38 shown in FIG. It is determined whether an input signal to that effect has been obtained. The input signal here is, for example, a signal indicating that when the paper feed tray is pulled out or set in the opening 22, or a signal indicating that when the opening / closing lid 20 is opened or closed. In addition, for example, when the carriage is displaced from the stop position by an external force such as a user, there is a signal indicating the fact.

  When making a positive determination in step 60, the sub CPU 32 determines whether or not the input signal from the sensor group 38 indicates a fatal error in step S62. Here, the fatal error is an error that becomes an obstacle to realizing the function of the MFP 10, and includes, for example, a case where the carriage is displaced from a correct position by an external force. This is the case, for example, when the user forcibly displaces the carriage from the correct stop position in the state in which the MFP 13 is shifted from the sleep mode to the active mode and then in the state in which the upper portion 13 of the MFP 10 is opened by the user. Etc.

  When determining that a fatal error has occurred in step S62, the sub CPU 32 prohibits the transition to the sleep mode in step S70. This is for displaying a screen that prompts the user to eliminate the error. Note that the prohibition of the transition to the sleep mode is canceled after the error is resolved.

  On the other hand, when making a negative determination in step S62, the sub CPU 32 determines in step S64 whether or not the input signal in step S60 should be accompanied by a user input operation thereafter. Here, what should be accompanied by the user's input operation is, for example, a case where a paper feed tray is set in the opening 22. In this case, the MFP 10 prompts the user to input characteristics such as the size and type of the newly set recording paper by displaying on the LCD 24b. On the other hand, the case where no input operation is performed is, for example, a case where the opening / closing lid 20 is closed.

  If the sub CPU 32 makes a positive determination in step S64 or makes a negative determination in step S60, the sub CPU 32 proceeds to step S68. In step S68, the sub CPU 32 sets the light sleep threshold Tth1 and the deep sleep threshold Tth2 to “15 s”, which is the longest time in the present embodiment. If the sub CPU 32 makes an affirmative determination in step S64, then the user should perform further input operations, and the setting for avoiding a situation in which the operability is impaired by shifting to the sleep mode. It is. If the sub CPU 32 makes a negative determination in step S60, for example, it is an input operation on the operation panel 24 other than the execution key, such as recording settings such as recording resolution and the number of recordings, and so on, there is a probability that the user will continue to input operations. This is a setting for avoiding a situation in which operability is impaired by shifting to the sleep mode.

  In contrast, if the negative determination is made in step S64, the sub CPU 32 sets the light sleep threshold Tth1 and the deep sleep threshold Tth2 to “10 s” in step S66. This is because the probability that the operability is impaired by shifting to the sleep mode is lower than when the sub CPU 32 makes a negative determination in step S60 or makes a positive determination in step S64. .

  On the other hand, if a negative determination is made in step S50, the sub CPU 32 detects the occurrence of an event that is in the active mode and the condition for shifting from the sleep mode to the active mode in step S72, or executes the task. Determine if it is a period. In the active mode, the sub CPU 32 determines in step S74 whether or not the event whose occurrence has been detected is an execution command for the generation process or the recording process by the PC 50. If the determination in step S74 is affirmative, the sub CPU 32 turns on the skip flag Fs in step S78. On the other hand, if the sub CPU 32 makes a negative determination in step S74, it determines whether or not the execution key has been operated in step S76. When the sub CPU 32 makes an affirmative determination in step S76 or when the process of step S78 is completed, the sub CPU 32 proceeds to step S56. That is, even in the active mode, when an affirmative determination is made in step S74 or an affirmative determination is made in step S76, the event that makes the transition from the sleep mode to the active mode is an event that has resulted in an affirmative determination. For the same reason, the light sleep mode threshold Tth1 and the deep sleep mode threshold Tth2 are shortened.

  On the other hand, if the negative determination is made in step S76, the sub CPU 32 sets the light sleep mode threshold Tth1 and the deep sleep mode threshold Tth2 to “15 s” in step S79. In this case, even if the light sleep mode threshold value Tth1 and the deep sleep mode threshold value Tth2 are shortened by the processing in steps S56 and S66, this is different from the situation assumed when shortened. This is because it is considered to have happened.

  The sub CPU 32 once ends the series of processes when the processes of steps S56, S66, S68, S70, and S79 are completed or when a negative determination is made in step S72.

  According to the embodiment described above, the following effects can be obtained.

  (1) The light sleep threshold Tth1 and the deep sleep threshold Tth2 are changed in accordance with the type of event that is a trigger for transition from the sleep mode to the active mode. As a result, it is possible to favorably predict the subsequent usage status by the user, so that it is possible to further reduce power consumption while avoiding a situation in which the operability of the MFP 10 is lowered by the user.

  (2) When the event type that triggers the transition from the sleep mode to the active mode is a generation process or recording process execution command, the light sleep threshold Tth1 and the deep sleep threshold Tth2 are set to the minimum values. As a result, it is possible to further reduce power consumption while avoiding a situation where the operability of the MFP 10 is lowered by the user.

  (3) The sensor group 38 detects that the type of event that has triggered the transition from the sleep mode to the active mode has changed the state of the MFP 10 for the part other than the input unit (operation panel 24); When this is not a fatal error and should not be accompanied by a user input operation, the light sleep threshold Tth1 and the deep sleep threshold Tth2 are shortened as compared to the case where it should be accompanied. As a result, it is possible to further reduce power consumption while avoiding a situation where the operability of the MFP 10 is lowered by the user.

  (4) When the event type that triggered the transition from the sleep mode to the active mode is an execution command for the generation process or the recording process by the PC 50, the light sleep mode is skipped when shifting from the active mode to the sleep mode. And moved to deep sleep mode. As a result, it is possible to further reduce power consumption while avoiding a situation where the operability of the MFP 10 is lowered by the user.

  (5) When the event type that triggered the transition from the sleep mode to the active mode is a fatal error, the user copes with the error by prohibiting the transition to the sleep mode. It can be made easy.

  (6) The light sleep threshold value Tth1 and the deep sleep threshold value Tth2 are set to the minimum values even when the execution command is for the generation process or the recording process in the active mode. In other words, when an event occurs in the active mode, the generation process and the recording process are performed while the light sleep threshold Tth1 and the deep sleep threshold Tth2 are returned to the reference value (here, “15s”) in principle. Exceptionally, the write sleep threshold value Tth1 and the deep sleep threshold value Tth2 were shortened. As a result, it is possible to further reduce power consumption while avoiding a situation where the operability of the MFP 10 is lowered by the user.

<Second Embodiment>
Hereinafter, the second embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  FIG. 7 shows a procedure of setting processing of the light sleep threshold Tth1 and the deep sleep threshold Tth2 according to the present embodiment. This processing is performed by the sub CPU 32 repeatedly executing the program stored in the ROM 34, for example, at a predetermined cycle. In FIG. 7, the same steps as those shown in FIG. 6 are given the same step numbers for the sake of convenience.

  As shown in the figure, in the present embodiment, the sub CPU 32 sets the light sleep threshold Tth1 and the deep sleep threshold Tth2 to different values. Specifically, the sub CPU 32 sets the light sleep threshold Tth1 to a value smaller than the deep sleep threshold Tth2. This is a setting for demonstrating the effect of reducing power consumption by quickly shifting to a mode for reducing power. Moreover, since the light sleep mode has higher responsiveness to the user's operation compared to the deep sleep mode, the operability does not deteriorate as much as when the conditions for shifting to the deep sleep mode are relaxed.

  Specifically, in step S56a, the sub CPU 32 sets the light sleep threshold Tth1 to “4s” and sets the deep sleep threshold Tth2 to “6s”. In step S66a, the sub CPU 32 sets the light sleep threshold Tth1 to “9s” and sets the deep sleep threshold Tth2 to “11s”. Further, in step S68a, the sub CPU 32 sets the light sleep threshold Tth1 to “14s” and sets the deep sleep threshold Tth2 to “16s”.

  According to this embodiment described above, in addition to the effects (1) to (6) of the first embodiment, the following effects can be obtained.

  (7) By making the light sleep threshold Tth1 and the deep sleep threshold Tth2 different, it is possible to improve the degree of freedom in designing the transition condition to each mode.

  (8) The light sleep threshold Tth1 is set to a value smaller than the deep sleep threshold Tth2. Thereby, the effect of reducing power consumption can be enhanced by quickly shifting to a mode for reducing power.

<Third Embodiment>
Hereinafter, the third embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  FIG. 8 shows a procedure for setting the light sleep threshold Tth1 and the deep sleep threshold Tth2 according to this embodiment. This processing is performed by the sub CPU 32 repeatedly executing the program stored in the ROM 34, for example, at a predetermined cycle. In FIG. 8, the same steps as those shown in FIG. 6 are given the same step numbers for the sake of convenience.

  As shown in the drawing, in the present embodiment, the light sleep threshold Tth1 and the deep sleep threshold Tth2 are generated when the execution of the generation process or the recording process is instructed by the PC 50, rather than when the execution key is operated. Set to a smaller value. That is, if the sub CPU 32 makes an affirmative determination in step S52 or step S74, the deep sleep threshold Tth2 is set to “4 s” in step S80. As described above, when the execution of the generation process or the recording process is instructed by the PC 50, it is highly likely that the user is not within reach of the MFP 10, and moreover than when the execution key is operated, This is a setting in view of the low possibility that the user will continue to operate.

  According to the present embodiment described above, the following effects can be obtained in addition to the effects according to the effects (1) to (6) of the first embodiment.

  (9) The light sleep threshold Tth1 and the deep sleep threshold Tth2 are set to smaller values when the generation process or the recording process is instructed by the PC 50 than when the execution key is operated. Thereby, the reduction effect of power consumption can be heightened, avoiding the fall of operativity by a user.

<Other embodiments>
As described above, the present invention has been described based on the embodiments, but the present invention is not limited to the above-described embodiments, and various modifications can be easily made without departing from the spirit of the present invention. Can be inferred. Examples of modifications are listed below.

  In the above-described embodiment, an example in which the processing illustrated in FIGS. 4 to 8 is executed by the sub CPU 32 has been described. However, these processing are not limited to the sub CPU 32, and for example, the main CPU 30, an ASIC, and a dedicated logic circuit. These processes may be executed by the cooperation of the sub CPU 32, the main CPU 30, the ASIC, and other logic integrated circuits.

  The technique for reducing the total power supply compared to the normal mode (active mode) is not limited to that illustrated in FIG. For example, at least one of the scanner 12 and the printer 14 may be turned off in the first energy saving mode (light sleep mode). Further, for example, the display on the LCD 24b may be stopped.

  The method for reducing the total power supply amount as compared with the first energy saving mode is not limited to the method illustrated in FIG. For example, touch panel input may be disabled in the second energy saving mode (deep sleep mode). For example, at least one of the scanner 12 and the printer 14 may be in a sleep mode.

  The energy saving mode is not limited to one having the two energy saving modes of the light sleep mode and the deep sleep mode, and may have only one sleep mode, for example. In addition, for example, a mode in which the total power supply amount is smaller than that in the deep sleep mode, or a mode in which the total power supply amount is smaller than that in the light sleep mode and the total power supply amount is greater than that in the deep sleep mode. The power saving in the energy saving mode may be performed in multiple stages.

  In the above embodiment, when the event that triggered the transition from the sleep mode to the active mode is an execution command from the PC 50, the light sleep mode is skipped when the transition from the active mode to the sleep mode is performed, and the transition to the deep sleep mode is performed. However, it is not limited to this. For example, even when an event that triggers the transition from the sleep mode to the active mode is issued by an operation on the operation panel 24 of the MFP 10, the light sleep mode is skipped when the transition from the active mode to the sleep mode is performed. You may transfer to sleep mode.

  However, even when both the light sleep mode and the deep sleep mode are provided, it is not essential to provide the light sleep mode skip processing.

  As a changing means, the light sleep threshold Tth1 and the deep sleep threshold Tth2 are set to the same value, or the light sleep threshold Tth1 and the deep sleep threshold regardless of the type of event that has triggered the transition to the active mode. The setting is not limited to one of making the threshold value Tth2 different. For example, the light sleep threshold Tth1 may be set to a value smaller than the deep sleep threshold Tth2 only when the execution key is turned on. Also, for example, the deep sleep threshold Tth2 is a fixed value that does not depend on the type of event that triggered the transition to the active mode, and can be changed according to the type of event only in the light sleep mode. Good.

  It is not essential that the light sleep threshold Tth1 be equal to or less than the deep sleep threshold Tth2. Further, the magnitudes of the light sleep threshold Tth1 and the deep sleep threshold Tth2 are not limited to those exemplified in the above embodiment.

  Communication with the PC 50 is not limited to means for performing wired communication (LAN I / F 40). For example, a transmission / reception apparatus for performing wireless communication may be used. In this case, the external device may be a multi-function portable terminal, a computer equipped with a function for communicating with the MFP 10 via a wireless LAN, or the like. Note that this does not mean that wireless communication uses radio waves, and may use infrared rays, for example.

  The fatal error is not limited to those exemplified in the above embodiment. Further, the prohibition means is not limited to the one that prohibits the transition to the energy saving mode, only for fatal errors. However, it is not essential to provide a prohibition means.

“About changing thresholds according to events that occur in active mode”
In the embodiment described above, the light sleep threshold Tth1 and the deep sleep threshold Tth2 are changed to the maximum values except for the execution command, but the present invention is not limited to this. For example, in the case of a state change detected by the sensor group 38 (limited to an event corresponding to the transition condition to the normal mode), the sub CPU 32 may set the same value as the processing in step S66. When an event that becomes a condition for shifting to the normal mode occurs in the active mode, the sub CPU 32 may change the light sleep threshold value Tth1 and the deep sleep threshold value Tth2 to a uniform maximum value. Furthermore, both the light sleep threshold value Tth1 and the deep sleep threshold value Tth2 are not limited to the maximum values by the sub CPU 32. For example, only the light sleep threshold value Tth1 may be changed to the maximum value by the sub CPU 32.

  The printer 14 is not limited to an ink jet type, and may be a laser printer, for example.

  The scanner 12 is not limited to the flat bed type.

  DESCRIPTION OF SYMBOLS 10 ... MFP (one embodiment of image forming apparatus), 24 ... Operation panel (one embodiment of input unit), 32 ... Sub CPU (one embodiment of power control unit), 40 ... LAN I / F 40 (of communication unit) One embodiment), 42... Power supply unit, S12... One embodiment of detection means and determination means, S34... One embodiment of normal mode shifting means, S14. Embodiment, S24 ... one embodiment of the second energy saving mode transition means, S52, S58, S60, S64 ... one embodiment of the specifying means, S56, S66, S56a, S66a, S80 ... one embodiment of the changing means, S60 ... One embodiment of state change detection means, S70... One embodiment of prohibition means.

Claims (9)

A processing unit for executing various processes;
A power supply unit for supplying power to the processing unit;
An image forming apparatus comprising: an energy saving mode for reducing a total power supply amount from the power supply unit to the processing unit; and a power control unit that performs switching control of a normal mode in which the total power supply amount is larger than the energy saving mode,
The processing executed by the processing unit includes at least one of generation processing for reading an original to generate image data and recording processing for recording an image obtained from the image data on a recording medium,
The power control unit
Detection means for detecting occurrence of an event as a condition for shifting from the energy saving mode to the normal mode;
Determination means for determining whether or not it is an execution period of the at least one process by the processing unit;
In the normal mode, a timing unit that counts a duration time during which the occurrence of the event is not detected by the detection unit and the determination unit does not determine the execution period;
Energy saving mode transition means for shifting from the normal mode to the energy saving mode when the measured duration is equal to or greater than a threshold having a finite length determined for shifting from the normal mode to the energy saving mode. When,
When an event is detected by the detection means during the energy saving mode, normal mode transition means for shifting to the normal mode;
A specifying means for specifying an event that is a trigger to shift to the normal mode;
Changing means for changing the threshold according to the type of event specified by the specifying means;
An image forming apparatus comprising:   The image forming apparatus according to claim 1, wherein the changing unit shortens the threshold when the event specified by the specifying unit is an instruction to execute the at least one process. An input unit for inputting instruction information by the user is provided,
The power control unit includes a state detection unit that detects a change in the state of the image forming apparatus separately from the input of the input unit,
The event to be detected by the detection unit includes a state change detected by the state detection unit,
The image forming apparatus according to claim 1, wherein the changing unit shortens the threshold value on condition that the event specified by the specifying unit is the state change. An input unit for inputting instruction information by the user is provided,
The power control unit includes a state detection unit that detects a change in the state of the image forming apparatus separately from the input of the input unit,
The changing means may be configured such that when the event specified by the specifying means is the state change and input of instruction information to the input unit is required in accordance with the state change, the specified event is changed to the state change. The threshold value is shortened as compared with a case where instruction information to the input unit is not necessary in accordance with the state change. Image forming apparatus. An input unit for inputting user instruction information;
A communication unit that receives instruction information from an external device via a network,
The event to be detected by the detection means includes input of instruction information related to execution of the at least one process to the input unit and reception of instruction information related to execution of the at least one process by the communication unit. ,
When the event specified by the specifying unit is reception of instruction information related to execution of the at least one process by the communication unit, the changing unit is configured to input the instruction information related to execution of the at least one process. 5. The image forming apparatus according to claim 1, wherein the threshold value is shortened as compared with a case where the input is input. An input unit for inputting instruction information by the user is provided,
The event to be detected by the detection means includes an input to the input unit,
The changing unit is configured such that when the event specified by the specifying unit is an input to the input unit and the input instruction information is execution of the at least one process, the specified event is 6. The threshold value according to claim 1, wherein the threshold value is shortened as compared with a case where the input instruction information is not an execution of the at least one process. 2. The image forming apparatus according to item 1. A communication unit that receives instruction information from an external device via a network;
The event to be detected by the detection means includes reception by the communication unit of instruction information regarding execution of the at least one process,
The energy saving mode includes a first energy saving mode and a second energy saving mode in which the total amount of supplied power is smaller than that of the first energy saving mode,
The energy saving mode transition means is configured to shift to the second energy saving mode after shifting from the normal mode to the first energy saving mode,
When the event specified by the specifying means is reception by the communication unit of instruction information related to the execution of the at least one process, the transition processing to the energy saving mode by the energy saving mode shifting means is performed from the normal mode to the first mode. 7. The apparatus according to claim 1, further comprising a second energy saving mode transition unit that changes to the transition from the normal mode to the second energy saving mode instead of shifting to the energy saving mode. 8. Image forming apparatus.   8. The apparatus according to claim 1, further comprising a prohibiting unit that prohibits the energy-saving mode transition unit from shifting to the energy-saving mode on condition that the event identified by the identifying unit is an error. The image forming apparatus described in 1. The processing executed by the processing unit includes display processing of a liquid crystal display device,
9. The image forming apparatus according to claim 1, wherein the energy saving mode is to reduce a light amount of a backlight of the liquid crystal display device as compared with the normal mode.

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