Electronic device and drive control method

Abstract

To provide an electronic device and a drive control method that can restrain deterioration in convenience and restrain an excessive current from flowing when a switching element transitions from an off state to an on state.SOLUTION: An image forming device 100 includes a power cutoff circuit 63 including a switching element that transitions, in response to start of output from a first power supply unit 61, from an off-state in which a power supply path is cut off to an on-state in which the power supply path is conducted, and transitions from the on-state to the off-state in response to stop of output from the first power supply unit 61, and a control unit 7 for stopping loads 40 to be used in a job being executed when the power supply from a commercial power source 200 is stopped during execution of the job and a duration of a state in which the power supply from the commercial power source 200 has been stopped exceeds a specific time based on a combination of the loads 40 to be used in the job being executed.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an electronic device and a drive control method. [Background technology]

[0002] 2. Description of the Related Art There is known an electronic device that includes a power supply unit that outputs power in response to power supplied from a commercial power source, and a plurality of loads that are driven by the power output from the power supply unit (see, for example, Patent Document 1).

[0003] The electronic device may be provided with a switching element and a backup power supply unit. The switching element is provided in a power supply path common to the plurality of loads, and transitions from an OFF state in which the power supply path is interrupted to an ON state in which the power supply path is conductive in response to start of output from the power supply unit, and transitions from the ON state to the OFF state in response to stop of output from the power supply unit. The backup power supply unit supplies power to the load used in the job when power supply from the commercial power source is stopped during execution of the job. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-228513 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the electronic device, if the load continues to be driven even after the output of the backup power supply unit is stopped, when power supply from the commercial power source is resumed, an excessive current (load current) may flow through the switching element as the switching element transitions from the off state to the on state, causing the switching element to break down.

[0006] In response to this, it is conceivable to immediately stop the load used in the job when the power supply from the commercial power source is stopped during the execution of the job, but in this case, even if the power supply from the commercial power source is resumed before the output of the backup power source is stopped, the operation of the load is stopped and the progress of the job is delayed, which reduces user convenience.

[0007] An object of the present invention is to provide an electronic device and a drive control method that can suppress a decrease in convenience and suppress an excessive current from flowing when a switching element transitions from an off state to an on state. [Means for solving the problem]

[0008] According to one aspect of the present invention, an electronic device includes a first power supply unit, a plurality of loads, a switching element, a second power supply unit, a measurement processing unit, and a stop processing unit. The first power supply unit outputs power in response to power supply from a commercial power source. Each of the loads is driven by the power output from the first power supply unit. The switching element is provided on a power supply path common to the plurality of loads, and transitions from an off state in which the power supply path is interrupted to an on state in which the power supply path is conductive in response to start of output from the first power supply unit, and transitions from the on state to the off state in response to stop of output from the first power supply unit. When power supply from the commercial power source is stopped during execution of a job, the second power supply unit supplies power to the load used in the job. When power supply from the commercial power source is stopped during execution of the job, the measurement processing unit measures the duration of a power supply stop state in which power supply from the commercial power source is stopped. When the duration of the power supply stop state measured by the measurement processing unit exceeds a specific time based on a combination of the loads used in the job being executed, the stop processing unit stops the load used in the job being executed.

[0009] A drive control method according to another aspect of the present invention is executed by an electronic device including a first power supply unit that outputs power in response to power supply from a commercial power source, a plurality of loads driven by the power output from the first power supply unit, a switching element that is provided in a power supply path common to the plurality of loads, transitioning from an off state for interrupting the power supply path in response to start of output from the first power supply unit to an on state for conducting the power supply path, and transitioning from the on state to the off state in response to stop of output from the first power supply unit, and a second power supply unit that supplies power to the loads used in a job when power supply from the commercial power source is stopped during execution of the job, and includes a measurement step and a stop step. In the measurement step, when power supply from the commercial power source is stopped during execution of the job, a duration of a power supply stop state in which power supply from the commercial power source is stopped is measured. In the stop step, when the duration of the power supply stop state measured in the measurement step exceeds a specific time based on a combination of the loads used in the job being executed, the loads used in the job being executed are stopped. Effect of the Invention

[0010] According to the present invention, it is possible to suppress a decrease in convenience and to suppress an excessive current from flowing when a switching element transitions from an OFF state to an ON state. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a cross-sectional view showing a configuration of an image forming apparatus according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a block diagram showing a system configuration of the image forming apparatus according to the embodiment of the present invention. [Diagram 3] FIG. 3 is a diagram showing a power supply path of the image forming apparatus according to the embodiment of the present invention. [Figure 4] FIG. 4 is a circuit diagram showing the configuration of the power supply cutoff circuit of the image forming apparatus according to the embodiment of the present invention. [Diagram 5]FIG. 5 is a flowchart showing an example of a connected device identification process executed in the image forming apparatus according to the embodiment of the present invention. [Figure 6] FIG. 6 is a flowchart showing an example of a drive control process executed in the image forming apparatus according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Note that the following embodiment is an example of the present invention, and is not intended to limit the technical scope of the present invention.

[0013] [Configuration of image forming apparatus 100] First, the configuration of an image forming apparatus 100 according to an embodiment of the present invention will be described with reference to Figures 1 to 4. In Figure 3, the image forming apparatus 100 is indicated by a two-dot chain line. In Figure 3, a detection signal SG11 input to the control unit 7, and a plurality of remote signals SG20 and a control signal SG31 output from the control unit 7 are indicated by dashed lines with arrows. In Figure 4, a power supply cutoff circuit 63 is indicated by a dashed line.

[0014] The image forming apparatus 100 is a multifunction machine having multiple functions such as a scanning function for reading an image of an original document, a printing function for forming an image based on image data, a fax function, and a copy function. The image forming apparatus 100 is an example of an electronic device of the present invention. The electronic device of the present invention may be an image forming apparatus such as a printer, a fax machine, or a copy machine. Furthermore, the electronic device of the present invention is not limited to an image forming apparatus.

[0015] As shown in FIGS. 1 and 2, an image forming apparatus 100 includes an ADF (Auto Document Feeder) 1, an image reading unit 2, an image forming unit 3, a sheet conveying unit 4, an operation display unit 5, a storage unit 6, and a control unit .

[0016] The ADF 1 transports documents to be read by the scanning function, and includes a document setting section, a plurality of transport rollers, a document holder, and a paper ejection section.

[0017] The image reading unit 2 realizes the scanning function. The image reading unit 2 includes a document table, a light source, a plurality of mirrors, an optical lens, and a CCD (Charge Coupled Device).

[0018] 1, the image forming unit 3 includes a photoconductor drum 11, a charging roller 12, an optical scanning device 13, a developing device 14, a toner container 15, a transfer roller 16, a cleaning device 17, a fixing device 18, and a paper discharge tray 19.

[0019] Photoconductor drum 11 is provided so as to be rotatable in the direction of the arrow shown in Fig. 1. Charging roller 12 is provided in contact with the circumferential surface of photoconductor drum 11 and charges the circumferential surface of photoconductor drum 11. Optical scanning device 13 irradiates the circumferential surface of photoconductor drum 11 charged by charging roller 12 with light based on image data. An electrostatic latent image is formed on the circumferential surface of photoconductor drum 11 by optical scanning device 13.

[0020] The developing device 14 uses toner to develop the electrostatic latent image formed on the circumferential surface of the photoreceptor drum 11. A toner container 15 supplies toner to the developing device 14. A transfer roller 16 transfers the electrostatic latent image (toner image) developed by the developing device 14 onto a sheet transported by the sheet transport unit 4. A cleaning device 17 cleans the circumferential surface of the photoreceptor drum 11 after the toner image has been transferred by the transfer roller 16.

[0021] The fixing device 18 fixes the toner image transferred onto the sheet by the transfer roller 16 onto the sheet. The sheet onto which the toner image has been fixed by the fixing device 18 is discharged onto a paper discharge tray 19.

[0022] The sheet transport unit 4 transports a sheet on which an image is formed by the image forming unit 3. As shown in FIG 1, the sheet transport unit 4 includes a paper feed cassette 21, a pickup roller 22, a paper feed roller 23, a plurality of first transport rollers 24, and a plurality of second transport rollers 25.

[0023] The sheet feed cassette 21 is detachably provided in the housing of the image forming apparatus 100, and stacks sheets to be supplied to the image forming unit 3. The pickup roller 22 picks up the topmost sheet from the sheet feed cassette 21 among the multiple sheets stacked in the sheet feed cassette 21.

[0024] The paper feed roller 23 transports the sheet picked up from the paper feed cassette 21 by the pickup roller 22 to a sheet supply path that leads to a position where the toner image is transferred by the transfer roller 16, via the fixing device 18, and to the paper output tray 19. A plurality of first transport rollers 24 are provided on the sheet supply path upstream of the fixing device 18 in the sheet transport direction, and transport the sheet to the fixing device 18 via the position where the toner image is transferred by the transfer roller 16. A plurality of second transport rollers 25 are provided on the sheet supply path downstream of the fixing device 18 in the sheet transport direction, and transport the sheet to the paper output tray 19.

[0025] The operation display unit 5 is a user interface of the image forming apparatus 100. The operation display unit 5 has a display unit such as a liquid crystal display that displays various information in response to control instructions from the control unit 7, and an operation unit such as operation keys or a touch panel that inputs various information to the control unit 7 in response to user operations.

[0026] The storage unit 6 is a non-volatile storage device. For example, the storage unit 6 is a non-volatile memory such as a flash memory. The storage unit 6 may be a solid state drive (SSD) or a hard disk drive (HDD).

[0027] The control unit 7 performs overall control of the image forming apparatus 100. As shown in FIG. 2, the control unit 7 includes a CPU 31, a ROM 32, and a RAM 33. The CPU 31 is a processor that executes various arithmetic processing. The ROM 32 is a non-volatile storage device in which information such as a control program for causing the CPU 31 to execute various processing is stored in advance. The RAM 33 is a volatile or non-volatile storage device used as a temporary storage memory (work area) for various processing executed by the CPU 31. The CPU 31 performs overall control of the image forming apparatus 100 by executing various control programs stored in advance in the ROM 32.

[0028] The control unit 7 may be a control unit provided separately from a main control unit that performs overall control of the image forming apparatus 100. The control unit 7 may be configured with an electronic circuit such as an application specific integrated circuit (ASIC).

[0029] 3, the image forming apparatus 100 includes a plurality of loads 40. For example, the image forming apparatus 100 includes a first load 41, a second load 42, a third load 43, a fourth load 44, and a fifth load 45.

[0030] The first load 41 is a motor that generates a rotational driving force for rotating the photoconductor drum 11.

[0031] The second load 42 is a motor that generates a rotational driving force for rotating the pressure roller included in the fixing device 18 .

[0032] The third load 43 is a motor that generates a rotational driving force for rotating the pick-up roller 22 and the paper feed roller 23 .

[0033] The fourth load 44 is a motor that generates a rotational driving force to rotate the plurality of first transport rollers 24.

[0034] The fifth load 45 is a motor that generates a rotational driving force for rotating the plurality of second transport rollers 25.

[0035] The first load 41, the second load 42, the third load 43, the fourth load 44, and the fifth load 45 are some of the multiple loads 40 provided in the image forming apparatus 100. The load 40 is not limited to a motor, and may be a solenoid, an electromagnetic clutch, a heater, or the like.

[0036] The multiple loads 40 are used in jobs executed by the image forming apparatus 100. The jobs include a print job, a copy job, a transmission job, and the like. The print job is a job for forming an image on a sheet based on image data input from an external information processing apparatus. The copy job is a job for copying an original. The transmission job is a job for scanning an original and transmitting the image read from the original to an external device.

[0037] 3, the image forming apparatus 100 includes a driving unit 50 provided corresponding to each of the loads 40. Each of the driving units 50 transitions between a driving state in which the load 40 is driven and a non-driving state in which the load 40 is not driven.

[0038] For example, the image forming apparatus 100 includes a first drive section 51, a second drive section 52, a third drive section 53, a fourth drive section 54, and a fifth drive section 55.

[0039] The first driving unit 51 is provided corresponding to the first load 41. The first driving unit 51 makes a state transition from the non-driving state to the driving state in response to an input of a first remote signal SG21 (see FIG. 3) output from the control unit 7. When the first driving unit 51 is in the driving state, it supplies power output from a power supply unit 61 (see FIG. 3) to the first load 41. Also, the first driving unit 51 makes a state transition from the driving state to the non-driving state in response to the control unit 7 stopping the output of the first remote signal SG21. When the first driving unit 51 is in the non-driving state, it stops the supply of power output from the power supply unit 61 to the first load 41.

[0040] The second driving unit 52 is provided corresponding to the second load 42. The second driving unit 52 makes a state transition from the non-driving state to the driving state in response to an input of a second remote signal SG22 (see FIG. 3) output from the control unit 7. The second driving unit 52 also makes a state transition from the driving state to the non-driving state in response to the control unit 7 stopping the output of the second remote signal SG22.

[0041] The third drive unit 53 is provided corresponding to the third load 43. The third drive unit 53 makes a state transition from the non-drive state to the drive state in response to an input of a third remote signal SG23 (see FIG. 3) output from the control unit 7. The third drive unit 53 also makes a state transition from the drive state to the non-drive state in response to the control unit 7 stopping the output of the third remote signal SG23.

[0042] The fourth drive unit 54 is provided corresponding to the fourth load 44. The fourth drive unit 54 makes a state transition from the non-drive state to the drive state in response to an input of a fourth remote signal SG24 (see FIG. 3) output from the control unit 7. The fourth drive unit 54 also makes a state transition from the drive state to the non-drive state in response to the control unit 7 stopping the output of the fourth remote signal SG24.

[0043] The fifth drive unit 55 is provided corresponding to the fifth load 45. The fifth drive unit 55 makes a state transition from the non-drive state to the drive state in response to an input of a fifth remote signal SG25 (see FIG. 3) output from the control unit 7. The fifth drive unit 55 also makes a state transition from the drive state to the non-drive state in response to the control unit 7 stopping the output of the fifth remote signal SG25.

[0044] The control unit 7 can individually switch the state of each of the driving units 50. Specifically, the control unit 7 can individually switch the state of each of the driving units 50 by individually controlling the output of a plurality of remote signals SG20 (see FIG. 3) corresponding to the plurality of driving units 50.

[0045] As shown in FIG. 3, the image forming apparatus 100 further includes a power supply unit 61, a zero-cross detection unit 62, a power cutoff circuit 63, a backup power supply unit 64, and a diode 65.

[0046] Power supply unit 61 outputs power in response to power supply from commercial power supply 200 (see FIG. 3). Specifically, power supply unit 61 is an AC-DC converter that converts an AC voltage output from commercial power supply 200 into a DC voltage of a predetermined voltage value and outputs the DC voltage. Power supply unit 61 is an example of a first power supply unit of the present invention.

[0047] Each of the loads 40 is driven by power output from a power supply unit 61 .

[0048] The zero-cross detector 62 is an electric circuit capable of detecting a zero-cross point of the AC voltage output from the commercial power supply 200. When the zero-cross detector 62 detects the zero-cross point, it outputs a detection signal SG11 indicating the detection of the zero-cross point. The detection signal SG11 output from the zero-cross detector 62 is input to the controller 7.

[0049] The power supply cutoff circuit 63 is provided in a power supply path common to the multiple loads 40 between the power supply unit 61 and the multiple loads 40. The power supply cutoff circuit 63 switches the power supply path between conduction and cutoff depending on whether or not a control signal SG31 output from the control unit 7 is input.

[0050] As shown in FIG. 4, the power supply cutoff circuit 63 includes a field effect transistor (FET) 71, a first resistor 72, a second resistor 73, a transistor 74, a third resistor 75, and a fourth resistor .

[0051] The FET 71 is a P-channel type MOSFET (Metal Oxide Semiconductor Field Effect Transistor). As shown in Fig. 4, the source terminal of the FET 71 is connected to the power supply unit 61. The source terminal of the FET 71 is connected to the gate terminal of the FET 71 via a first resistor 72. The gate terminal of the FET 71 is connected to the collector terminal of a transistor 74 via a second resistor 73. The drain terminal of the FET 71 is connected to a plurality of loads 40 via a plurality of driving units 50 (see Fig. 3).

[0052] The transistor 74 is an NPN type transistor. As shown in Fig. 4, the base terminal of the transistor 74 is connected to the control unit 7 via a third resistor 75. The base terminal of the transistor 74 is connected to the emitter terminal of the transistor 74 via a fourth resistor 76. The emitter terminal of the transistor 74 is connected to ground.

[0053] In the power supply cutoff circuit 63, when the control signal SG31 is input from the control unit 7, the transistor 74 transitions from an off state to an on state. As a result, the power supply unit 61 is connected to the ground via the first resistor 72 and the second resistor 73. Therefore, a potential difference occurs between the source terminal and the gate terminal of the FET 71, and the FET 71 switches from an off state to an on state.

[0054] In addition, in the power supply cutoff circuit 63, when the input of the control signal SG31 from the control unit 7 is stopped, the transistor 74 transitions from the on state to the off state. This causes the potential difference between the source terminal and the gate terminal of the FET 71 to disappear, and the FET 71 switches from the on state to the off state.

[0055] That is, the control unit 7 can arbitrarily switch the power supply path between conduction and interruption during power supply from the commercial power source 200. For example, when the operation mode of the image forming apparatus 100 transitions from a normal mode to a power saving mode in which power consumption is reduced compared to the normal mode, the control unit 7 stops input of the control signal SG31 to interrupt the power supply path. Also, when the operation mode of the image forming apparatus 100 transitions from the power saving mode to the normal mode, the control unit 7 resumes input of the control signal SG31 to make the power supply path conductive.

[0056] FET 71 is provided in the power supply path. When a control signal SG31 is input to a power supply cutoff circuit 63, FET 71 transitions from an ON state, which causes the current path to be conductive, to an OFF state, which causes the current path to be cut off, in response to a stop in output of the power supply unit 61 due to a power outage or the like. Also, when a control signal SG31 is input to the power supply cutoff circuit 63, FET 71 transitions from an OFF state to an ON state in response to start (restart) of output of the power supply unit 61 due to an end of a power outage or the like. FET 71 is an example of a switching element of the present invention.

[0057] The backup power supply unit 64 supplies power to the load 40 used in the job when power supply from the commercial power source 200 is stopped during execution of the job. Specifically, the backup power supply unit 64 is a storage battery. The backup power supply unit 64 is charged in advance in preparation for a stop of output from the power supply unit 61 due to a power outage or the like. The backup power supply unit 64 is an example of a second power supply unit of the present invention.

[0058] The diode 65 is provided between the plurality of loads 40 side of the power supply interruption circuit 63 in the power supply path and the backup power supply unit 64. Specifically, the anode terminal of the diode 65 is connected to the backup power supply unit 64. Moreover, the cathode terminal of the diode 65 is connected to the plurality of loads 40 side of the power supply interruption circuit 63 in the power supply path.

[0059] Backup power supply unit 64 outputs power at a lower voltage than power supply unit 61. As a result, while power supply unit 61 is receiving power from commercial power supply 200 and outputting power, the power output by backup power supply unit 64 is limited. Furthermore, when power supply unit 61 stops outputting power due to a stop in power supply from commercial power supply 200, the power output limit by backup power supply unit 64 is lifted.

[0060] In the image forming apparatus 100, if the load 40 continues to be driven even after the power supply from the commercial power source 200 is stopped and the output from the backup power source unit 64 is stopped, when the power supply from the commercial power source 200 is resumed, an excessive current (load current) may flow through the FET 71 as the FET 71 transitions from the OFF state to the ON state, causing the FET 71 to break down.

[0061] In response to this, it is conceivable to immediately stop the load 40 used in the job when the power supply from the commercial power source 200 is stopped during the execution of the job. However, in this case, even if the power supply from the commercial power source 200 is resumed before the output of the backup power source unit 64 is stopped, the operation of the load 40 is stopped and the progress of the job is delayed, which reduces user convenience.

[0062] In contrast, in the image forming apparatus 100 according to an embodiment of the present invention, as described below, it is possible to suppress a decrease in convenience and to suppress the flow of excessive current when the FET 71 transitions from the off state to the on state.

[0063] [Configuration of control unit 7] Next, the configuration of the control unit 7 will be described in more detail with reference to FIG.

[0064] As shown in FIG. 2, the control unit 7 includes a measurement processing unit 81 and a stop processing unit .

[0065] Specifically, a drive control program for causing the CPU 31 to function as each of the above-mentioned processing units is stored in advance in the ROM 32 of the control unit 7. The CPU 31 executes the drive control program stored in the ROM 32 to function as each of the above-mentioned processing units.

[0066] The drive control program may be recorded on a computer-readable recording medium such as a CD, a DVD, or a flash memory, and may be read from the recording medium and stored in a storage device such as the storage unit 6. Some or all of the processing units included in the control unit 7 may be configured with electronic circuits. The drive control program may be a program for causing a plurality of processors to function as each processing unit included in the control unit 7.

[0067] When the power supply from the commercial power source 200 is stopped during the execution of the job, the measurement processing unit 81 measures the duration of the power supply stop state in which the power supply from the commercial power source 200 is stopped.

[0068] Specifically, the measurement processing unit 81 determines whether or not the power supply from the commercial power source 200 has stopped, based on the output state of the detection signal SG11 by the zero-cross detection unit 62. For example, when the next detection signal SG11 is not output even after a predetermined time has elapsed since the zero-cross detection unit 62 output the previous detection signal SG11, the measurement processing unit 81 determines that the power supply from the commercial power source 200 has stopped.

[0069] The stop processing unit 82 stops the load 40 used in the job being executed when the duration of the power supply stop state measured by the measurement processing unit 81 exceeds a specific time based on a combination of loads 40 used in the job being executed.

[0070] For example, in the image forming apparatus 100, first table data indicating the correspondence between the combination of the loads 40 used in the job to be executed and the specific time is stored in advance in the storage unit 6. Here, the specific time corresponding to the combination of the loads 40 is set based on the output duration of the backup power supply unit 64 (the time until the output stops) when the combination of the loads 40 is driven by the power output from the backup power supply unit 64.

[0071] For example, when the image forming apparatus 100 is powered on, the stop processing unit 82 identifies an optional device connected to the image forming apparatus 100. For example, the ADF 1 is an optional device. The optional devices also include an additional paper feed unit and the like.

[0072] In addition, when the job is executed, the stop processing unit 82 identifies one or more loads 40 to be used in the job to be executed, based on the content of the job to be executed and the optional equipment identified when the image forming apparatus 100 is powered on.

[0073] Then, the stop processing unit 82 sets the specified time based on the result of identifying one or more loads 40 used in the job to be executed and the first table data.

[0074] When the duration of the power supply stop state measured by the measurement processing unit 81 exceeds the specific time, the stop processing unit 82 stops the load 40 by stopping the output of the remote signal SG20 to the drive unit 50 corresponding to the load 40 used in the job being executed.

[0075] The specific time may be set based on a combination of loads 40 used in the job and the voltage of commercial power source 200. For example, instead of the first table data, second table data indicating a correspondence relationship between the specific time and a combination of one or more loads 40 and the voltage of commercial power source 200 used in the job to be executed may be stored in storage unit 6. In this case, image forming apparatus 100 may include a peak value detection unit capable of detecting a peak value of the output voltage of commercial power source 200.

[0076] [Connected device identification process] An example of the procedure of the connected device identification process executed by the control unit 7 in the image forming apparatus 100 will be described below with reference to Fig. 5. Here, steps S11, S12, etc. indicate the numbers of the process steps (steps) executed by the control unit 7.

[0077] When the image forming apparatus 100 is powered on, the control unit 7 executes the connected device identification process.

[0078] <Step S11> First, in step S11, the control unit 7 determines whether the optional device is connected to the image forming apparatus 100 or not.

[0079] Here, when the control unit 7 determines that the optional device is connected to the image forming apparatus 100 (Yes side of S11), the control unit 7 shifts the process to step S12. On the other hand, when the optional device is not connected to the image forming apparatus 100 (No side of S11), the control unit 7 ends the connected device identification process.

[0080] <Step S12> In step S12, the control unit 7 identifies the optional device connected to the image forming apparatus 100. Here, the process of step S12 is executed by the stop processing unit 82 of the control unit 7.

[0081] Specifically, the control unit 7 communicates with the optional device connected to the image forming apparatus 100 to obtain the identification information of the optional device from the optional device.

[0082] [Drive control processing] Next, with reference to FIG. 6, a drive control method of the present invention will be described along with an example of a procedure of a drive control process executed by the control unit 7 in the image forming apparatus 100.

[0083] When the job is executed, the control unit 7 executes the drive control process in parallel with the job.

[0084] <Step S21> First, in step S21, the control unit 7 sets the specific time. Here, the process of step S21 is executed by the stop processing unit 82 of the control unit 7.

[0085] Specifically, the control unit 7 identifies one or more loads 40 used in the job to be executed, based on the content of the job to be executed and the optional device identified when the image forming apparatus 100 is powered on. Then, the control unit 7 sets the specified time based on the result of identifying the one or more loads 40 used in the job to be executed and the first table data.

[0086] <Step S22> In step S22, the control unit 7 determines whether or not the job being executed has been completed.

[0087] Here, if the control unit 7 determines that the job has ended (Yes in S22), it ends the drive control process. If the job has not ended (No in S22), the control unit 7 shifts the process to step S23.

[0088] <Step S23> In step S23, the control unit 7 determines whether or not the power supply from the commercial power source 200 has stopped.

[0089] Specifically, when the next detection signal SG11 is not output even after a predetermined time has elapsed since the zero-cross detection unit 62 output the previous detection signal SG11, the control unit 7 determines that power supply from the commercial power source 200 has stopped.

[0090] Here, when the control unit 7 determines that the power supply from the commercial power source 200 has stopped (Yes side of S23), it shifts the process to step S24. On the other hand, when the power supply from the commercial power source 200 has not stopped (No side of S23), the control unit 7 shifts the process to step S22.

[0091] <Step S24> In step S24, the control unit 7 starts measuring the duration of the power supply stop state. Here, the processes of steps S23 and S24 are an example of a measurement step of the present invention, and are executed by the measurement processing unit 81 of the control unit 7.

[0092] <Step S25> In step S25, the control unit 7 determines whether or not the duration of the power supply stop state has exceeded the specific time set in the process of step S21.

[0093] Here, when the control unit 7 determines that the duration of the power supply stop state has exceeded the specific time (Yes side of S25), it shifts the process to step S26. On the other hand, when the power supply from the commercial power source 200 is resumed before the duration of the power supply stop state has exceeded the specific time (No side of S25), the control unit 7 stops measuring the duration of the power supply stop state and shifts the process to step S22.

[0094] <Step S26> In step S26, the control unit 7 stops the load 40 used in the job being executed. Here, the process of step S26 is an example of a stop step of the present invention, and is executed by the stop processing unit 82 of the control unit 7.

[0095] Specifically, the control unit 7 stops the output of the remote signal SG20 to the driving unit 50 corresponding to the load 40 used in the job being executed, thereby stopping the load 40.

[0096] <Step S27> In step S27, the control unit 7 determines whether the FET 71 has transitioned to the on state.

[0097] Specifically, the control unit 7 determines that the FET 71 has transitioned to the on state when a predetermined time has elapsed since the power supply from the commercial power source 200 was resumed.

[0098] Here, if the control unit 7 determines that the FET 71 has transitioned to the on state (Yes side of S27), it shifts the process to step S28. On the other hand, if the FET 71 has not transitioned to the on state (No side of S27), the control unit 7 waits for the transition of the FET 71 to the on state in step S27.

[0099] <Step S28> In step S28, the control unit 7 restarts the driving of the load 40 that was stopped in the process of step S26.

[0100] In this way, in the image forming apparatus 100, when the duration of the power supply stop state exceeds the specific time based on the combination of the loads 40 used in the job being executed, the loads 40 used in the job being executed are stopped. This makes it possible to continue driving the loads 40 when the power supply from the commercial power source 200 is resumed before the output of the backup power source unit 64 is stopped, and to stop driving the loads 40 when the power supply from the commercial power source 200 is not resumed before the output of the backup power source unit 64 is stopped. This makes it possible to suppress a decrease in convenience and to suppress an excessive current from flowing when the FET 71 transitions from an off state to an on state. [Explanation of symbols]

[0101] 1 ADF 2 Image reading section 3. Image forming section 4 Sheet transport section 5 Operation display section 6 Memory section 7 Control section 40 Load 50 Drive unit 61 Power supply section 62 Zero cross detection section 63 Power supply cutoff circuit 64 Backup power supply unit 71 FET 81 Measurement processing section 82 Stop processing section 100 Image forming device 200 Commercial power supply

Claims

1. a first power supply unit that outputs power in response to power supply from a commercial power source; a plurality of loads driven by power output from the first power supply unit; a switching element that is provided in a power supply path common to the plurality of loads, transitioning from an off state in which the power supply path is interrupted to an on state in which the power supply path is conductive in response to start of output of the first power supply unit, and transitioning from the on state to the off state in response to stop of output of the first power supply unit; a second power supply unit that supplies power to the load used in a job when power supply from the commercial power supply is stopped during execution of the job; a measurement processing unit that measures a duration of a power supply interruption state in which the power supply from the commercial power supply is interrupted when the power supply from the commercial power supply is interrupted during the execution of the job; a stop processing unit that stops the loads used in the job being executed when a duration of the power supply stop state measured by the measurement processing unit exceeds a specific time based on a combination of the loads used in the job being executed; An electronic device comprising:

2. the specific time is set based on a combination of the loads used in the job and a voltage of the commercial power supply; 2. The electronic device according to claim 1.

3. The image reading unit reads an image of a document, and / or the image forming unit forms an image based on image data.

3. The electronic device according to claim 1 or 2.

4. a first power supply unit that outputs power in response to power supply from a commercial power source; a plurality of loads that are driven by the power output from the first power supply unit; a switching element that is provided in a power supply path common to the plurality of loads, the switching element transitioning from an off state that interrupts the power supply path to an on state that conducts the power supply path in response to start of output from the first power supply unit, and transitioning from the on state to the off state in response to stop of output from the first power supply unit; and a second power supply unit that, when power supply from the commercial power source is stopped during execution of a job, supplies power to the loads used in the job, a measuring step of measuring a duration of a power supply interruption state in which the power supply from the commercial power source is interrupted when the power supply from the commercial power source is interrupted during the execution of the job; a stop step of stopping the loads used in the job being executed when the duration of the power supply stop state measured by the measurement step exceeds a specific time based on a combination of the loads used in the job being executed; A drive control method comprising:

Images