JP2010146367A - Electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely turn off a power source of a device even when the power source of the device can not be turned off due to runaway of a controller when turning off the power source of the device after the end of the shutdown processing by the controller. <P>SOLUTION: When a main switch 41 is on, the power source from an AC power source is supplied through the main switch 41 to a power circuit 43. When the main switch 41 is turned off, a detection signal 101 is inputted to the controller 2. The controller 2 outputs a control signals 102 for turning on a switch means 42. The power source from the AC power source is supplied through the switch means 42 to the power circuit 43. The controller 2 turns off the switch means 42 after the end of the shutdown processing. When the controller 2 runs away and the switch means 42 can not be turned off, a breaker 44 is turned off. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electronic apparatus including a control unit that determines whether or not power supply is necessary when a main switch is turned off, and turns off the power supply when power supply becomes unnecessary.

  Electronic devices such as digital multifunction peripherals (MFPs) and servers / personal computers that combine functions of copy, facsimile, printer, and scanner, such as servers and personal computers, have various software backgrounds even when they are not used directly by users. Is working with. Therefore, if power is suddenly turned off as a result of accidentally turning off the power switch or unplugging the power cord, the necessary data cannot be saved to the non-volatile memory, and it can be started normally when the power is turned on next time. It may disappear.

  As an image forming apparatus capable of avoiding problems due to such sudden power off, a power supply circuit that receives AC power and supplies DC power to a load, and a main switch interposed between the power supply circuit and the AC power supply And a switch means inserted between the power supply circuit and the AC power supply to turn on / off in response to a control signal, a switch state detecting means for detecting an on / off state of a main switch, and the switch The on / off control of the means is performed by the control signal, the necessity / unnecessity of the power supply to the load by the power supply circuit is managed, and the detection signal of the switch state detecting means switches from on to off of the main switch when necessary. In addition, there is an image forming apparatus including a control unit (controller) that turns off the switch unit when power supply to a load is no longer necessary (see Patent Document 1).

However, in the case of this image forming apparatus, there is a problem in that power supply to the load by the power supply circuit is not stopped even if the user turns off the main switch when the control unit runs away and the control signal cannot be output. .
JP 2002-312075 A

  The present invention has been made to solve such problems, and its purpose is to determine whether or not power supply is necessary when the main switch is turned off, and to turn on the power supply when power supply becomes unnecessary. In an electronic device provided with a control means for turning off, it is to ensure that the power can be turned off even when an abnormality occurs in the control means.

  An electronic device according to the present invention includes a power supply circuit that receives power from an AC power supply and supplies DC power to a load, a first switch as a main switch provided in a power supply path from the AC power supply to the power supply circuit, A second switch connected in parallel to the first switch; and a control means for controlling on / off of the second switch, the control means when the first switch is turned off, In an electronic device that determines whether or not power supply to a load is necessary and controls the second switch to be turned off when it is not necessary, a power supply path from the AC power source to the power supply circuit via the second switch is forcibly Means for automatically shutting off, or a watchdog timer incorporated in the control means, and means for supplying the output to the second switch as a signal for controlling the second switch to turn off, It is characterized by having a means for forcibly turning off the second switch.

[Action]
According to the present invention, a power supply circuit that receives power from an AC power supply and supplies DC power to a load, a first switch as a main switch provided in a power supply path from the AC power supply to the power supply circuit, A second switch connected in parallel to the first switch, and a control means for controlling on / off of the second switch, and the control means has the load when the first switch is turned off. In the electronic device that determines whether or not the power supply to the power supply is necessary and controls the second switch to be turned off when it is unnecessary, when the first switch is turned off and the power supply to the load is not needed, the control means A means for forcibly cutting off the power supply path from the AC power source to the power supply circuit via the second switch when an abnormality occurs, or a watchdog timer built in the control means; Is supplied from the AC power source to the second switch as a signal for controlling the output of the second switch to turn off the second switch, or forcibly turns off the second switch. The power supply path to the power supply circuit is cut off.

  According to the present invention, when the main switch is turned off, it is determined whether or not power supply is necessary, and an abnormality occurs in the control means in the electronic device including the control means that turns off the power supply when power supply becomes unnecessary. Even if it is done, the power can be surely turned off.

The best mode for carrying out the present invention will be described below with reference to the drawings.
[First Embodiment]
FIG. 1 is a block diagram of an electronic apparatus according to the first embodiment of the present invention. This electronic apparatus is an image forming apparatus.

  The image forming apparatus 1 includes a controller 2 having an input port (input interface) 21 and an output port (output interface) 22, an engine 3, and a DC power supply / AC control board 4. The controller 2 controls the entire image forming apparatus 1. The engine 3 is a printer engine that prints an image on a sheet, a scanner engine that reads an image of a document, or the like. The DC power source / AC control board 4 is a board (board) on which a circuit for converting power supplied from the AC power source into DC power and supplying it to each part (here, the controller 2 and the engine 3) in the apparatus is mounted. It is.

  The DC power supply / AC control board 4 includes a main switch 41, switch means 42 including a relay driver 42a and a relay 42b, a power supply circuit 43, and a breaker 44.

  One end of the breaker 44 is connected to a power line from an AC power source, and the other end is connected to one end (input side) of the main switch 41 and one end (input side) of the relay 42b. The breaker 44 can be manually opened and closed (on / off) by the user. When the breaker 44 is closed, the AC power source and the input sides of the main switch 41 and the relay 42b are connected by a power line.

  The main switch 41 includes two open / close contacts that are opened / closed (on / off) in conjunction with a user's on / off operation, and one of them, that is, an open / close that receives AC power through the breaker 44. The fixed contact (AC power supply contact) X2 corresponding to the contact (AC switching contact) is connected to the input side of the power supply circuit 43 by the power line, and the switching contact (DC switching) connected to the other, that is, the ground (GND). The fixed contact (low voltage DC contact) X1 corresponding to the contact) is connected to the input port 21 of the controller 2 by a signal line.

  Therefore, when the main switch 41 is turned on (contacts are closed) when the breaker 44 is on (closed), power from the AC power supply is supplied to the power circuit 43 through the main switch 41. Further, the state of the low voltage fixed contact X <b> 1 (ground potential = 0) is input to the input port 21 of the controller 2. On the other hand, when the main switch 41 is turned off (contacts are opened), AC power is not supplied to the power supply circuit 43. Further, the state of the low voltage fixed contact X <b> 1 (relatively high potential) is input to the input port 21 of the controller 2. That is, the detection signal 101 of the on / off state of the main switch 41 is input to the input port 21. That is, the signal from the DC switching contact “Low” means that the main switch 41 is “on (closed)”, and “High” means that the main switch 41 is “off (open)”. It is given to port 21.

  The other end (output side) of the relay 42 b is connected to the input side of the power supply circuit 43. Therefore, when the breaker 44 is on and the relay 42b is turned on, the power from the AC power supply is supplied to the power circuit 43 through the relay 42b. On the other hand, when the relay 42b is turned off (the contact is opened), the power from the AC power source is not supplied to the power circuit 43. The relay driver 42a receives the control signal 102 supplied from the output port 22 of the controller 2 and controls the relay 42b according to the level (“High” or “Low”). Details of the control signal 102 will be described later.

  The controller 2 controls the engine 3 and monitors the state thereof to determine the necessity / unnecessity of power supply by the power supply circuit 43. If necessary, the main switch 41 is detected from the detection signal 101 output from the main switch 41 After the on / off state of 41 is detected and off is detected, the relay 42b of the switch means 42 is turned off by the control signal 102 when power supply to the engine 3 and the controller 2 becomes unnecessary.

First, the operation when the contact is closed by the user turning on the main switch 41 for the purpose of operating the image forming apparatus 1 will be described.
When the contact of the main switch 41 is closed, an AC voltage is input to the power supply circuit 43. The power supply circuit 43 converts the AC voltage into a DC voltage having a predetermined level necessary for the operations of the engine 3 and the controller 2 and supplies the converted DC voltage. As a result, the engine 3 and the controller 2 become operable, and the image forming apparatus 1 performs a predetermined operation.

  At this time, since the detection signal 101 indicating the on / off state of the main switch 41 is “Low”, the controller 2 is notified that the main switch 41 is on (closed). The controller 2 does not output the control signal 102 to the switch means 42 from the start of the DC power supply from the power supply circuit 43, and the switch means 42 maintains the off (open) state. For this reason, there is no AC power supply to the power supply circuit 43 via the switch means 42, and there is little energy loss while the main switch 41 is ON.

Next, an operation when the user turns off the main switch 41 and the contact is turned off (open) will be described.
When the contact of the main switch 41 is opened, the AC power supply to the power supply circuit 43 is interrupted. For this reason, the DC output voltage of the power supply circuit 43 disappears after a holding time due to the input / output capacitor capacity in the power supply circuit 43. Since the detection signal 101 indicating the on / off state of the main switch 41 becomes “High”, the controller 2 is immediately notified that the main switch 41 is in the open state. Therefore, the controller 2 is notified that the main switch 41 is OFF during the DC voltage holding time of the power supply circuit 43.

  The controller 2 switches the control signal 102 to the switch means 42 from the off instruction ("Low") to the on instruction ("High") to turn on the contact of the relay 42b and to the power supply circuit 43. AC power supply is started. For this reason, the power supply circuit 43 starts conversion from AC to DC again and starts DC power supply to the engine 3 and the controller 2 before the holding time of the DC output voltage of the power supply circuit 43 elapses. When this is completed, the termination process (shutdown process) is performed, and the control signal 102 to the switch means 42 is switched from the on instruction ("High") to the off instruction ("Low"). Therefore, the relay 42b is cut off. As a result, the AC power supply to the power supply circuit 43 through the switch means 42 is cut off, and after the DC voltage holding time of the power supply circuit 43 has elapsed, the DC output of the power supply circuit 43 disappears.

  On the other hand, when the image forming apparatus 1 is executing a job, the control signal 102 is output to the switch means 42 to turn on (close) the contact of the relay 42 b and start the AC power supply to the power supply circuit 43. Therefore, the power supply circuit 43 starts conversion from AC to DC again and starts DC power supply to the engine 3 and the controller 2 before the holding time of the DC output voltage of the power supply circuit 43 elapses. The job that was being executed can be completed without interruption.

  The controller 2 performs an end process (shutdown process) when the job is normally completed, and changes the control signal 102 to the switch means 42 from an on instruction ("High") to an off instruction ("Low"). ), The relay 42b is cut off. As a result, the AC power supply to the power supply circuit 43 through the switch means 42 is cut off, and after the DC voltage holding time of the power supply circuit 43 has elapsed, the DC output of the power supply circuit 43 disappears.

  Such power control will be described in more detail with reference to FIGS. FIG. 2 is a timing chart showing the state of each unit when the main switch 41 of the image forming apparatus 1 is turned on and then turned off during standby. FIG. 3 is a timing chart of the job after the main switch 41 of the image forming apparatus 1 is turned on. It is a timing diagram which shows the state of each part at the time of turning off during execution.

  In these drawings, A indicates the on / off state of the main switch 41. B is a detection signal 101 for the on / off state of the main switch 41, where “Low” indicates on and “High” indicates off, and C indicates the AC power supply state to the power supply circuit 43. D is a control signal 102 for turning on / off the switch means 42, where “High” indicates on and “Low” indicates off, E indicates the DC output of the power supply circuit 43, and t1 to t5 indicate timings. Show.

First, the case where the main switch 41 is turned on and then turned off during standby will be described with reference to FIG.
When the user turns on the main switch 41 at timing t1, supply of AC power to the power supply circuit 43 starts. The power supply circuit 43 starts DC output to the controller 2 and the engine 3 from the timing t2, and the controller 2 starts activation processing. At timing t3 after the start-up process is completed, the on / off detection signal 101 (B in the figure) of the main switch 41 is "Low (on)", so the control signal 102 (D in the figure) output from the controller 2 is "Low". (Off) ", and no AC power is supplied from the switch means 42 to the power supply circuit 43.

  Next, when the user turns off the main switch 41 at timing t4, the AC power supply (C in the figure) to the power supply circuit 43 is cut off. Further, in synchronization with the timing t 4 when the main switch 41 is turned off, “the detection signal 101 (B in the figure) of the on / off state of the main switch 41 is“ high (off) ”” → “control output from the controller 2. When the signal 102 (D in the figure) becomes “High (on)” and AC power is supplied from the switch means 42 to the power supply circuit 43 (C in the figure), AC to the power supply circuit 43 via the main switch 41 is performed. Although the power supply is momentarily reduced, the AC power is supplied again via the switch means 42 before the DC output holding time of the power supply circuit 43 elapses, so that the output (E in the figure) of the power supply circuit 43 drops to the engine 3 and the controller 2. Continuously supplied.

  Further, at the timing t4 when the main switch 41 is turned off, the controller 2 checks the operation state of itself and the engine 3, and the result is a standby state, so the shutdown process is immediately started. When the shutdown process is completed, the control signal 102 (D in the figure) is set to “Low (off)” to cut off the AC power supply (C in the figure) from the switch means 42 to the power supply circuit 43. As a result, the DC output of the power circuit 43 to the engine 3 and the controller 2 is also turned off, and the power is turned off.

  Next, the state of each unit when the main switch 41 is turned on and then turned off during job execution will be described with reference to FIG. Here, the state of each part from turning on the main switch 41 to turning it off is the same as in FIG.

  The controller 2 checks the operating state of itself and the engine 3 at the timing t4 when the main switch 41 is turned off. As a result, if it is confirmed that the job is being executed, the job is continued and the shutdown process is started after the job ends. To do. The subsequent processing is the same as in FIG.

  Next, the operation in the case where the controller 2 runs away after the user turns off the main switch 41, the power is not cut off, and the power is forcibly turned off by the breaker 44 will be described with reference to the timing chart of FIG. To do. Here, the process is the same as in FIG. 2 until the user turns off the main switch 41 and the controller 2 starts the shutdown process.

  As shown in FIGS. 2 and 3, the AC power supply from the switch means 42 to the power supply circuit 43 is cut off by originally setting the control signal 102 (D in the drawing) to “Low (off)” after the shutdown process is completed. However, if the controller 2 goes out of control after the start of the shutdown process, the control signal 102 does not become “Low (off)”, so that the AC power supply from the switch means 42 to the power supply circuit 43 cannot be cut off and the power supply cannot be turned off. End up.

  Therefore, in the present embodiment, when the user turns off the breaker 44, the AC input to the switch means 42 is cut off, whereby the AC power supply from the switch means 42 to the power supply circuit 43 is cut off. As a result, the DC output (E in the figure) from the power circuit 43 to the engine 3 and the controller 2 is also turned off, and the power is turned off.

  As described above, according to the image forming apparatus of the first embodiment of the present invention, even if the controller 2 runs away and the power of the apparatus cannot be turned off under the control of the controller 2, the breaker 44 forcibly turns off the power. Even when the controller 2 goes out of control, the power can be surely turned off.

[Second Embodiment]
FIG. 5 is a block diagram of an image forming apparatus according to the second embodiment of the present invention. In this figure, the same reference numerals as those in FIG. 1 are assigned to the same or corresponding parts as in FIG. 1 (first embodiment).

  The image forming apparatus according to the present embodiment removes the breaker 44 from the image forming apparatus (FIG. 1) according to the first embodiment, and a watch dog timer 23 is provided in the controller 2. Is connected to the signal line of the control signal 102 from the output port 22 by a wired OR.

  FIG. 6 is a timing chart showing the states of the respective parts when the main switch 41 of the image forming apparatus 1 of the present embodiment is turned on, turned off during standby, and the controller 2 runs away after the shutdown process is started. In this figure, the process is the same as in FIG. 2 until the user turns off the main switch 41 and the controller 2 starts the shutdown process.

  As described above with reference to FIG. 4, if the controller 2 runs away after the start of the shutdown process, the control signal 102 does not become “Low (off)”, so that the AC power supply from the switch means 42 to the power supply circuit 43 cannot be cut off. The power will not turn off. In the present embodiment, when the controller 2 runs away, the watchdog timer 23 is not set, so that its output (G in FIG. 6) becomes “Low” and is supplied to the relay 42a. As a result, since the relay 42b is cut off, the AC power supply to the power supply circuit 43 through the switch means 42 is cut off, and the DC output (E in the figure) from the power supply circuit 43 to the engine 3 and the controller 2 is turned off. The device is turned off.

  Thus, according to the image forming apparatus of the second embodiment of the present invention, even if the controller 2 runs away and the switch means 42 cannot be turned off by the control signal 102 from the controller 2, the output of the watch dog timer 23 is output. Therefore, the power can be surely turned off even if the controller 2 goes out of control without increasing the hardware cost.

[Third Embodiment]
FIG. 7 is a block diagram of an image forming apparatus according to the third embodiment of the present invention. In this figure, the same reference numerals as those in FIG.

  The image forming apparatus according to the present embodiment removes the breaker 44 from the image forming apparatus according to the first embodiment (FIG. 1) and forcibly manually inputs the relay driver 42a on the DC power supply / AC control board 4. The auxiliary switch 45 that can be grounded is connected to the signal line of the control signal 102 on the DC / AC control board 4 by wired OR.

  FIG. 8 is a timing chart showing the state of each part when the main switch 41 of the image forming apparatus 1 of the present embodiment is turned on, turned off during standby, and the controller 2 runs away after the shutdown process is started. In this figure, the process is the same as in FIG. 2 until the user turns off the main switch 41 and the controller 2 starts the shutdown process.

  As described above, when the controller 2 goes out of control after the start of the shutdown process, the control signal 102 does not become “Low (off)”, so that the AC power supply from the switch means 42 to the power supply circuit 43 cannot be cut off and the power supply is not turned off. Become. In this embodiment, by turning on the auxiliary switch 45, the input signal level of the relay driver 42a is set to "Low", the relay 42b is cut off, and the AC power supply to the power supply circuit 43 via the switch means 42 is cut off. As a result, the DC output from the power supply circuit 43 to the engine 3 and the controller 2 is also turned off, and the apparatus is turned off.

  Thus, according to the image forming apparatus of the third embodiment of the present invention, even if the controller 2 runs away and the switch means 42 cannot be turned off by the control signal 102 from the controller 2, the auxiliary switch 45 forces Therefore, even if the controller 2 goes out of control without significant cost increase, the power can be surely turned off.

[Fourth Embodiment]
FIG. 9 is a block diagram of an image forming apparatus according to the fourth embodiment of the present invention. In this figure, the same reference numerals as in FIG. 7 are assigned to the same or corresponding parts as in FIG. 7 (third embodiment).

  The image forming apparatus according to the present embodiment has an operation panel 5 connected to the controller 2 of the image forming apparatus according to the third embodiment. The operation panel 5 is used for notifying the user of the state of the apparatus and for inputting the setting of the apparatus by the user.

  In the image forming apparatus of the present embodiment, the state of each unit from when the user turns on the main switch 41 to when it is turned off is the same as that of the third embodiment (FIG. 8). The state after the main switch 41 is turned off differs in that processing for the operation panel 5 is added.

FIG. 10 is a flowchart of the operation in the image forming apparatus according to the present embodiment from when the main switch 41 is turned off until the apparatus is turned off.
When the main switch 41 is turned off (step S1), the detection signal 101 indicating the on / off state of the main switch 41 is turned off "High" (step S2), and the control signal 102 for controlling the on / off of the switch means 42 is generated. It is turned on “High” (step S3).

  When AC power supply from the switch means 42 to the power supply circuit 43 is started, even if AC power supply to the power supply circuit 43 via the main switch 41 is momentarily dropped, the switch means before the DC output holding time of the power supply circuit 43 elapses. Since AC power supply starts again via 42, DC power supply continues to the engine 3 and the controller 2 without dropping, so that the power supply continuation state is displayed on the operation panel 5 (step S4).

  Next, the presence / absence of a job is determined (step S5). If there is a job, the shutdown process is started immediately after the end of the job, and if there is no job (step S6).

  Next, it is determined whether or not the shutdown process has been completed (step S7), and the control signal 102 is turned off "Low" after completion (step S8). As a result, the AC power supply from the switch means 42 to the power supply circuit 43 is cut off, so that the DC output from the power supply circuit 43 to the engine 3 and the controller 2 is also turned off, and the apparatus is turned off (step S9).

  According to the fourth embodiment of the present invention, even if the user does not check the state of the main switch 41, the user can see the display on the operation panel 5 and the main switch 41 is turned off to see whether it is in a normal state. It is possible to determine whether the power supply is continued thereafter.

[Fifth Embodiment]
The block diagram of the image forming apparatus of the fifth embodiment of the present invention is the same as that of the fourth embodiment (FIG. 9). In the present embodiment, when the main switch 41 is turned off by the user, whether the power supply continuation state is maintained after displaying that the power supply continuation state is displayed on the operation panel 5, or whether the process proceeds to the shutdown process The point which performs the process according to a user's selection instruction | command is a difference from 4th Embodiment.

  FIG. 11 is a flowchart of operations in the image forming apparatus according to the present exemplary embodiment from when the main switch 41 is turned off until the apparatus is turned off. In this figure, the same or corresponding steps as those in FIG. 10 (fourth embodiment) are denoted by the same reference numerals as those in FIG.

  As shown in FIG. 11, the process from turning off the main switch 41 (step S1) to determining the presence or absence of a job (step S5) is the same as in the fourth embodiment. When it is determined in step S5 that there is no job (S5: No), that is, when the apparatus is on standby when the user turns off the main switch 41, or when the user turns off the main switch 41, the job is If there is, when it is completed, a selection screen for “continue power supply” or “shutdown” is displayed on the operation panel 5 (step S10), and the user selects a process on the operation panel 5 (step S11). .

  When the user selects “continue power supply” (step S12: No), power supply is continued until the user selects “shutdown” on the selection screen of the operation panel 5. When “Shutdown” is selected (step S12: Yes), the processing is the same as in the fourth embodiment.

  According to the fifth embodiment of the present invention, after the main switch 41 is turned off, the power supply continuation state can be maintained even after necessary processing is completed, and the power can be turned off at a desired timing.

[Sixth Embodiment]
The block diagram of the image forming apparatus of the sixth embodiment of the present invention is the same as that of the fourth embodiment (FIG. 9). In the image forming apparatus of the present embodiment, the operation flow from when the main switch 41 is turned off until the apparatus is turned off is almost the same as that of the fifth embodiment (FIG. 11). It is different from the fifth embodiment in that a buzzer on the operation panel 5 is sounded when the power supply continuation state is displayed.

  FIG. 12 is a flowchart of an operation in the image forming apparatus according to the present embodiment from when the main switch 41 is turned off until the apparatus is turned off. In this figure, the same or corresponding steps as those in FIG. 11 (fifth embodiment) are denoted by the same reference numerals as those in FIG.

  As shown in FIG. 12, the process from turning off the main switch 41 (step S1) to displaying on the operation panel 5 that the power supply is being continued (step S4) is the same as in the fifth embodiment. In the present embodiment, when step S4 is executed and the power supply continuation state is displayed on the operation panel 5, a process of sounding a buzzer on the operation panel 5 is added in the next step S13. The subsequent processing is the same as in the fifth embodiment.

  According to the sixth embodiment of the present invention, for example, when the device administrator is at a location slightly away from the device, it can be sure that a third party has intentionally or mistakenly turned off the main switch 41. it can.

[Seventh Embodiment]
The block diagram of the image forming apparatus of the seventh embodiment of the present invention is the same as that of the fourth embodiment (FIG. 9). In the image forming apparatus of the present embodiment, the operation flow from when the main switch 41 is turned off until the apparatus is turned off is almost the same as that of the sixth embodiment (FIG. 12), and the user can operate the image forming apparatus. The difference from the sixth embodiment is that the buzzer on the operation panel 5 is stopped when “continue power supply” is selected on the panel 5.

  FIG. 13 is a flowchart of the operation in the image forming apparatus according to the present embodiment from when the main switch 41 is turned off until the apparatus is turned off. In this figure, the same or corresponding steps as those in FIG. 12 (sixth embodiment) are denoted by the same reference numerals as those in FIG.

  As shown in FIG. 13, the process from turning off the main switch 41 (step S1) to determining whether the user has selected the shutdown process on the operation panel 5 (step S12) is the same as in the sixth embodiment. In this embodiment, when it is determined that “continue power supply” is selected (S12: No), the buzzer is stopped (step S14), and power is supplied until “shutdown” is selected on the selection screen of the operation panel 5. continue. Since the subsequent processing when shutdown is selected is the same as that of the sixth embodiment, description thereof is omitted.

  According to the seventh embodiment of the present invention, when the user selects the “continue power supply state” process, the buzzer sound is eliminated, so that the user can use the device with peace of mind even in a quiet environment such as an office.

1 is a block diagram of an image forming apparatus according to a first embodiment of the present invention. FIG. 3 is a timing diagram illustrating the state of each unit when the main switch is turned on and then turned off during standby in the image forming apparatus according to the first exemplary embodiment of the present invention. FIG. 4 is a timing diagram illustrating the state of each unit when the main switch is turned on and then turned off during job execution in the image forming apparatus according to the first exemplary embodiment of the present invention. In the image forming apparatus according to the first embodiment of the present invention, a timing chart showing an operation in a case where the controller runs out of control after the user turns off the main switch, the power is not turned off, and the power is forcibly turned off by the breaker. It is. It is a block diagram of the image forming apparatus of the 2nd Embodiment of this invention. FIG. 10 is a timing diagram illustrating the state of each unit when the main switch is turned on and then turned off during standby in the image forming apparatus according to the second embodiment of the present invention, and the controller runs out of control after the start of the shutdown process. It is a block diagram of the image forming apparatus of the 3rd Embodiment of this invention. FIG. 10 is a timing diagram illustrating the state of each unit when the main switch is turned on and then turned off during standby in the image forming apparatus according to the third exemplary embodiment of the present invention, and the controller runs out of control after starting the shutdown process. It is a block diagram of the image forming apparatus of the 4th Embodiment of this invention. FIG. 10 is a flowchart of an operation in the image forming apparatus according to the fourth exemplary embodiment of the present invention from when the main switch is turned off until the apparatus is turned off. FIG. 10 is a flowchart of an operation in the image forming apparatus according to the fifth exemplary embodiment of the present invention from when the main switch is turned off until the apparatus is turned off. FIG. 10 is a flowchart of an operation from the time when a main switch is turned off until the power of the apparatus is turned off in an image forming apparatus according to a sixth embodiment of the present invention. FIG. 10 is a flowchart of an operation in an image forming apparatus according to a seventh embodiment of the present invention from when a main switch is turned off until the apparatus is turned off.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 2 ... Controller, 3 ... Engine, 4 ... DC power supply / AC control board, 5 ... Operation panel, 22 ... Watchdog timer, 41 ... Main switch, 42 ... switch means, 43 ... power supply circuit, 44 ... breaker, 45 ... auxiliary switch, 101 ... detection signal of main switch on / off state, 102 ... switch Means on / off control signal.

Claims (9)

A power supply circuit that receives power from an AC power supply and supplies DC power to a load, a first switch as a main switch provided in a power supply path from the AC power supply to the power supply circuit, and a parallel connection to the first switch And a control means for controlling on / off of the second switch. The control means determines whether or not power supply to the load is required when the first switch is turned off. In an electronic device that controls whether the second switch is turned off when unnecessary,
An electronic apparatus comprising: means for forcibly blocking a power supply path from the AC power source to the power supply circuit via the second switch. The electronic device according to claim 1,
The electronic device is characterized in that the means for forcibly blocking is a manually operable switch connected between the AC power source and the second switch. The electronic device according to claim 2,
The electronic device is characterized in that the manually operable switch is a breaker. A power supply circuit that receives power from an AC power supply and supplies DC power to a load, a first switch as a main switch provided in a power supply path from the AC power supply to the power supply circuit, and a parallel connection to the first switch And a control means for controlling on / off of the second switch. The control means determines whether or not power supply to the load is required when the first switch is turned off. In an electronic device that controls whether the second switch is turned off when unnecessary,
An electronic apparatus comprising: a watchdog timer incorporated in the control means; and means for supplying the output to the second switch as a signal for controlling the second switch to be turned off. A power supply circuit that receives power from an AC power supply and supplies DC power to a load, a first switch as a main switch provided in a power supply path from the AC power supply to the power supply circuit, and a parallel connection to the first switch And a control means for controlling on / off of the second switch. The control means determines whether or not power supply to the load is required when the first switch is turned off. In an electronic device that controls whether the second switch is turned off when unnecessary,
An electronic apparatus comprising means for forcibly turning off the second switch. The electronic device according to claim 5,
The means for forcibly turning off is a manually operable switch and means for supplying the output of the switch to the second switch as a signal for controlling the second switch to turn off. machine. In the electronic device according to any one of claims 1 to 6,
An operation panel; and display information creation means for creating information to be displayed on the operation panel. The display information creation means is configured such that the first switch is off and the second switch is on. An electronic device characterized in that information indicating that the power supply is in a continuous state is created. The electronic device according to claim 7,
An electronic apparatus comprising: means for outputting a sound for notifying that the power supply is in a continuous state when the first switch is off and the second switch is on. The electronic device according to claim 7,
The display information creating means creates information for allowing a user to select maintenance of a power supply continuation state or power supply stop.

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