JP2010093900A - Power supply control device, and electronic apparatus with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and reliably prevent overvoltage from being applied to a power supply even when high-voltage power deviating from apparatus specifications is supplied to an image forming apparatus. <P>SOLUTION: A PLC unit (power supply control device) 7 provided in an image forming apparatus 1 includes: a PLC communication-power supply control unit 42 that communicates with other equipment through a power line 34; and a sub-power switch 43 that is placed between the power line and a power supply (power supply) 15 and switches on/off power supplied from the power line to the power supply. The PLC communication-power supply control unit controls the operation of the sub-power switch based on the results of detection by a voltage detection unit. When the voltage detected at the voltage detection unit deviates from the specified voltage of the image forming apparatus, the PLC communication-power supply control unit keeps the sub-power switch off to prevent power from being supplied to the power supply. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a power supply control device that protects a power supply device for a commercial AC power supply from overvoltage, and an electronic apparatus including the power supply control device.

  2. Description of the Related Art Conventionally, electronic devices (for example, printers, facsimiles, copiers, multifunction peripherals and other image forming apparatuses, PCs (Personal Computers) and other information processing apparatuses) are input from a commercial alternating current (hereinafter referred to as AC) power line. A power supply device that converts the generated power into a predetermined voltage and then supplies the power to a plurality of AC loads in the device in parallel. And in this kind of power supply devices, those equipped with overvoltage protection means to protect electronic devices from overvoltage caused by lightning surge or power line noise (preventing failure and abnormal operation of electronic parts etc.) are widespread is doing.

For example, in a power supply apparatus that inputs from a commercial AC power line and supplies power to a plurality of loads in parallel, a fuse (overcurrent interrupting means) having a characteristic of surge energy <Joule integral value is replaced with a metal oxide varistor (overvoltage protection means). There is known a power supply device that is connected in series and arranged between current shunt nodes or upstream lines (see Patent Document 1). In this power supply device, the fuse is not blown by energy caused by an instantaneous current such as a lightning surge, but is cut off with a margin by the ON current when the varistor is ON. For example, during the production of a 100V power supply device (inspection process or the like), even when 200V power is accidentally input, the current is surely cut off.
JP 2000-134794 A

  However, the above-described prior art requires a configuration in which a predetermined fuse is connected in series to the metal oxide varistor, and a different voltage is input, such as 200V-type power being input to a 100V specification power supply device. In such a case, although the fuse is blown and the varistor is protected, there is a problem that after that, a repair work is required to operate the power supply device (electronic device) normally.

  The present invention has been made in view of such circumstances, and it is possible to easily and reliably prevent an overvoltage from being applied to a power supply device even when high-voltage power different from the device specifications is supplied. It is a main object of the present invention to provide a power control device that can be used and an electronic device including the power control device.

  In order to solve the above problems, a power supply control device according to the present invention is a power supply control device that controls power supply from a power line to a power supply device, and communicates with another device via the power line. And a switch unit that is interposed between the power line and the power supply device and switches on / off of the power supply, the power line communication unit detects the voltage of the power line, and based on the detection result, the switch unit It is characterized by controlling the operation.

  According to the present invention, inappropriate power supply to the power supply device can be easily cut off by detecting the voltage of the power line by the power line communication unit and controlling the operation of the switch unit. Therefore, even when high-voltage power different from the device specification is supplied, an excellent effect is obtained that it is possible to easily and reliably prevent an overvoltage from being applied to the power supply device.

  A first invention made to solve the above problem is a power supply control device that controls power supply from a power line to a power supply device, and a power line communication unit that communicates with another device via the power line; A switch unit that is interposed between the power line and the power supply device and switches on / off of the power supply, and the power line communication unit detects a voltage of the power line, and based on the detection result, The operation is controlled.

  According to this, by detecting the voltage of the power line by the power line communication unit and controlling the operation of the switch unit, inappropriate power supply to the power supply device can be easily cut off. Therefore, even when high-voltage power different from the device specification is supplied, it is possible to easily and reliably prevent an overvoltage from being applied to the power supply device.

  The power line communication unit may be configured to turn off the switch unit when detecting a different voltage different from a predetermined reference voltage.

  According to this, when power having a voltage different from the device specification is supplied, it is possible to easily and reliably prevent an overvoltage from being applied to the power supply device.

  The third invention may further include an abnormality notifying unit that notifies the operator of the abnormality in the power supply when the power line communication unit detects a voltage different from a predetermined reference voltage.

  According to this, it is possible to promptly recognize an abnormality in power supply (application of overvoltage) by an abnormality notification (for example, warning sound or warning display) by the abnormality notification unit.

  According to a fourth aspect of the present invention, when the power line communication unit detects a voltage different from a predetermined reference voltage, the power line communication unit notifies the other device of the abnormality in the power supply via the power line. It can be set as the structure to do.

  According to this, even when the operator is away from the apparatus, the operator can promptly recognize an abnormality in power supply using power line communication.

  The power line communication unit may be interposed between the power line and the power supply device to relay power from the power line.

  According to this, it is possible to prevent an overvoltage from being applied to the power supply device with a simple configuration in which the power communication unit relays power supply from the power line to the power supply device.

  According to a sixth aspect of the invention, there is provided an electronic apparatus including the power supply control device according to any one of the first to fifth aspects of the invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing an appearance of an image forming apparatus provided with a power supply control device according to the present invention, and FIG. 2 is a functional block diagram showing a main part of the image forming apparatus of FIG.

  An image forming apparatus (electronic device) 1 includes a main control unit 2 that comprehensively controls various operations of the apparatus, a printer control unit 3 that controls a process of printing image data on recording paper, and an automatic document feeder (ADF). 4, a scanner control unit 5 for controlling a process for transporting recording paper, a process for optically scanning a document image by a CCD (Charge Coupled Device) sensor and generating image data, and a telephone network or the Internet (not shown). A facsimile control unit 6 that performs facsimile communication according to a predetermined communication protocol, and a PLC (Power Line Communication) unit 7 that performs power line communication according to a predetermined communication protocol via a power line network (not shown), a copy function, It is configured as a multifunction machine having a print function, a scanner function, a facsimile communication function, a power line communication function, and the like. The main control unit 2 has an image processing unit 8 that performs various types of image processing (compression / decompression of image data, shading correction, gamma correction, etc.) of the read image.

  The image forming apparatus 1 includes a panel control unit 13 that controls an operation panel 12 provided with various operation keys and a display monitor, a sensor control unit 14 that controls various sensors (not shown), and a commercial AC power source. A power supply unit (power supply device) 15 is provided that converts power supplied from (for example, voltage 100V, 240V) into power of a predetermined voltage and supplies it to each part of the device.

  The power supply unit 15 supplies power (for example, power to a high-voltage power supply unit 21 that supplies high-voltage (for example, +3 kV) power to a charging device or the like of a photoreceptor (not shown) and a fixing coil or the like of an IH (Induction Heating) fixing device (not shown) IH power supply unit 22 that supplies + 800V), and low-voltage power supply unit 23 that supplies low-voltage power (for example, + 24V, + 10.5V, + 5.0V, + 3.3V) to each of the above-described devices. Yes. The power supply unit 15 is connected to a commercial AC power supply via the PLC unit 7, and the PLC unit 7 functions as a power supply control device that controls power supply to the power supply unit 15 as will be described later.

  Although not shown, the main control unit 2, printer control unit 3, scanner control unit 5, FAX control unit 6, PLC unit 7, panel control unit 13, sensor control unit 14 and the like are controlled according to a predetermined control program. The CPU includes a CPU to be executed, a ROM in which a control program is stored, and a RAM that provides a work area for controlling the CPU.

  FIG. 3 is a configuration diagram showing a more detailed configuration around the PLC unit 7 and the power supply unit 15 in FIG. The PLC unit 7 is electrically connected to the power line 34 constituting the power line network on the premises by inserting the plug 32 attached to the power connector 31 into the plug insertion port 33, and is supplied from the power line 34 to the power source unit 15. Relay the power. A main power switch (hereinafter abbreviated as “SW”) 35 including a mechanical switch is provided in the wiring on the downstream side of the power connector 31, and the operator can turn on / off the power supply to the image forming apparatus by operating the main power SW 35. Is possible. The power line network is connected to an information processing apparatus (in this case, a PC 37 having a PLC modem 36) provided with PLC communication means for the purpose of managing the image forming apparatus.

  The PLC unit 7 functions as a PLC modem that detects the voltage of power supplied from the power line 34 and a PLC communication / power control unit (power line) that controls power supply to the power supply unit 15. Communication section) 42. On the further downstream side of the main SW 35, a sub power switch (switch unit) 43 composed of a normally open type electronic switch is provided, and the PLC communication / power control unit 42 detects the detection result of the voltage detection unit 41. The operation of the sub power switch 43 is controlled based on the above.

  In the power supply unit 15, power (for example, AC 100 V) supplied from the PLC unit 7 is supplied to the IH power supply unit 22 and the low-voltage power supply unit 23. Although not shown, the IH power supply unit 22 is a known circuit including a resonance circuit having a resonance capacitor connected in parallel to the exciting coil, a rectifier circuit that converts AC power into DC power, an inverter circuit having a switching element, and the like. Consists of The low-voltage power supply unit 23 includes a known circuit including a rectifier circuit, a transformer, and the like, similar to the voltage detection unit 41 illustrated in FIG. The high-voltage power supply unit 21 is composed of a known circuit including a transformer and the like, and boosts and outputs DC power (+ 24V) supplied from the low power supply unit.

  In the above configuration, when the main power supply SW35 is turned on, power is supplied from the power line 34 to the PLC unit 7 (voltage detection unit 41, PLC communication / power supply control unit 42). Therefore, the PLC communication / power control unit 42 turns on the sub power switch 43 when the voltage (for example, AC 100 V) detected by the voltage detection unit 41 matches the specification voltage (reference voltage) of the image forming apparatus. To supply power to the power supply unit 15. On the other hand, when the voltage (for example, AC 240 V) detected by the voltage detection unit 41 is different from the specification voltage (for example, AC 100 V) of the image forming apparatus, the PLC communication / power control unit 42 turns off the sub power switch 43. As it is, power is not supplied to the power supply unit 15. At this time, the PLC communication / power supply control unit 42 notifies the operator of the power supply abnormality by the buzzer (abnormality notification unit) 44 and simultaneously notifies the PC 37 of the power supply abnormality via the power line network. be able to.

  In this way, inappropriate power supply to the power supply unit 15 is facilitated by detecting the voltage of the supplied power by the PLC unit 7 connected to the power line network (power line 34) and controlling the operation of the sub power switch 43. Since it is configured to be able to shut off, it is possible to prevent an overvoltage from being applied to the power supply unit 15 even when high-voltage power different from the device specification is supplied from the power line 34. In this case, the PLC unit 7 that performs power line communication is designed to operate in a relatively wide voltage range (for example, 100 V to 240 V). That is, if the power supply unit 15 is designed so that it can be operated directly in the above voltage range, the current consumption in the power supply unit 15 is large, so the circuit of the power supply unit 15 becomes enormous and the cost increases. However, even if the PLC unit 7 is designed so that it can operate directly in the above voltage range, the current consumption in the PLC unit 7 is small, so the PLC unit 7 can be a simple circuit. In addition, when the voltage (for example, AC100V) in the power line 34 is lower than the specification voltage (for example, AC240V) of the apparatus, the PLC communication / power supply control unit 42 keeps the sub power switch 43 in the OFF state. There is an advantage that the malfunction of the image forming apparatus due to insufficient voltage can be prevented.

  FIG. 4 is a block diagram showing a detailed configuration of the PLC communication / power control unit 42 in FIG. The PLC communication / power control unit 42 includes a circuit module 51 that constitutes a PLC modem. Necessary voltages (for example, +1.2 V, +3.3 V, +12 V) are supplied to the circuit module 51 from a switching power supply 52 including a rectifier, a switching element, a high-frequency transformer, and the like (not shown).

  The circuit module 51 includes a main IC 61 that comprehensively controls the operation of the PLC modem. The digital signal is converted into a predetermined level analog signal when data is transmitted, and the analog signal is converted into a predetermined level digital signal when data is received. AFE (Analog Front End) IC 62, driver IC 63 for switching on / off of transmission signal and reception signal, coupler 64 for superimposing PLC analog signal on power line, band pass filters 65, 66, Ethernet (registered trademark) PHY IC 67 , And a modular jack (RJ45) 68 are provided.

  The main IC 61 includes a CPU 71, a PLC / MAC block 72 that manages a MAC layer (Media Access Control layer), and a PLC / PHY block 73 that manages a PHY layer (Physical layer). The CPU 71 is connected to a memory 74 that stores various processing information. The AFE / IC 62 includes a DA converter (DAC) 81, an AD converter (ADC) 82, and variable amplifiers 83 and 84. The coupler 64 includes a transformer 85 and coupling capacitors 86 and 87.

  In the PLC communication / power control unit 42 configured as described above, transmission data input from the modular jack 68 is sent to the main IC 61 via the Ethernet PHY / IC 67, where a digital signal is generated by performing digital signal processing. Is done. This digital signal is converted into an analog signal by the DA converter 81 of the AFE / IC 62 and output from the power connector to the power line via the band-pass filter 65, the driver IC 63, and the coupler 64. On the other hand, the received signal from the power connector 31 (power line) is sent to the band pass filter 66 via the coupler 64 and converted into a digital signal by the AD converter 82 of the AFE / IC 62, and the digital signal is converted into the main IC 61. And converted into digital received data by performing digital signal processing.

  Further, in the PLC communication / power control unit 42, when the main power switch 35 shown in FIG. 2 is turned on, the main IC 61 acquires a detection signal (here, voltage) from the voltage detection unit 41, and the detection signal When it is determined that the voltage of the power supplied from the power line matches the specification voltage of the apparatus based on the information obtained from the above, an operation instruction signal (ON command) is sent to the sub power switch 43.

  FIG. 5 is a configuration diagram showing a detailed configuration of the voltage detection unit 41 in FIG. The voltage detection unit 41 includes a rectifier circuit 91 in which a bridge is formed by four diodes, a primary side electrolytic capacitor 92 for suppressing ripple of supplied power, a secondary side electrolytic capacitor 93, and a transformer 94 for converting voltage. And resistors 95, 96 and the like.

  Electric power (commercial AC) supplied from the power connector 31 is converted into direct current in the rectifier circuit 91 and then converted into a predetermined voltage by the transformer 94. Here, for example, the voltage output to the PLC communication / power control unit 42 is set to 1.0 V when the supplied power is 100 VAC and 2.4 V when the supplied power is 240 VAC. Is done. The PLC communication / power supply control unit 42 acquires the output voltage (1.0 V, 2.4 V, etc.) as the detection result of the voltage of the power line 34. When the output voltage exceeds a predetermined reference value, the switching control IC 97 controls the switching pulse of the switch element 98 so as to drop the output voltage from the transformer 94, thereby appropriately holding the output voltage.

  FIG. 6 is a flowchart showing a flow of an abnormality detection operation for the supplied power performed by the PLC unit 7 in FIG.

  First, when the main power supply SW35 is turned on by the operator (S101: Yes), the PLC communication / power supply control unit 42 acquires the detection result of the voltage from the voltage detection unit 41, and supplies the power supplied from the power line 34. It is determined whether or not the voltage is 100V (S102). When the voltage of the supplied power is 100V, the PLC communication / power control unit 42 determines whether or not the specification voltage of the image forming apparatus 1 is 100V (S103). Therefore, when the PLC communication / power control unit 42 determines that the voltage of the supplied power matches the specification voltage (Yes), it turns on the sub power switch 43 (S104). Is supplied and the image forming apparatus 1 is activated (S105). Note that the specification voltage information can be stored in advance in the memory 74 (see FIG. 4), for example.

  On the other hand, in step S103, when the PLC communication / power control unit 42 determines that the specification voltage is not 100V, the buzzer 44 gives the operator an abnormality in power supply (the supply power voltage and the device specification voltage are different). At the same time, the PC 37 is notified of power supply abnormality via the power line network (S106). Thereby, it is possible to promptly recognize an abnormality in power supply to an operator in the vicinity of the apparatus or in a place away from the apparatus. In this case, the notification of abnormality via the power line network is notified to a specific information processing device (for example, only the PC 37) based on information such as a MAC address (Media Access Control address) or all devices by broadcast transmission. Or can be notified.

  If the supply power voltage is not 100 V in step S102, the PLC communication / power control unit 42 further determines whether the supply power voltage is 240 V (S107). If the voltage of the supplied power is 240V, then the PLC communication / power control unit 42 determines whether or not the specification voltage of the image forming apparatus 1 is 240V (S108), and thereafter executes steps 104 to S106. To do.

  If the supply power voltage is not 240 V in step S107, the PLC communication / power supply control unit 42 determines that a power supply abnormality has occurred (S109), and the buzzer 44 notifies the operator of the power supply abnormality (in the power supply). At the same time, the PC 37 is notified of the power supply abnormality via the power line network (S110).

  In addition, although the processing procedure on the assumption that the power supply of the supplied power is 100 V or 240 V is shown here, the same processing as in steps S102 to S106 is added to other different voltages as well. Is possible.

  The power supply control device of the present invention and the electronic apparatus including the same can easily and reliably prevent an overvoltage from being applied to the power supply device even when high-voltage power different from the device specification is supplied. The present invention is useful as a power supply control device that protects a power supply device for commercial AC power supply from overvoltage and an electronic device equipped with the power supply control device.

1 is a perspective view showing an external appearance of an image forming apparatus including a power supply control device according to the present invention. 1 is a functional block diagram showing the main part of the image forming apparatus of FIG. Configuration diagram showing a detailed configuration around the PLC unit and the power supply unit in FIG. Configuration diagram showing a detailed configuration of the PLC communication / power control unit in FIG. The block diagram which shows the detailed structure of the voltage detection part in FIG. FIG. 3 is a flowchart showing the flow of the abnormality detection operation of the supplied power in the PLC unit in FIG.

Explanation of symbols

1 Image forming device (electronic equipment)
2 Main control unit 7 PLC unit (power control unit)
8 Image Processing Unit 15 Power Supply Unit (Power Supply Device)
21 High Voltage Power Supply Unit 22 IH Power Supply Unit 23 Low Voltage Power Supply Unit 24 High Voltage Power Supply Unit 31 Power Supply Connector 32 Plug 33 Plug Plug 34 Power Line 35 Main Power Supply SW
37 PC
41 Voltage Detection Unit 42 PLC Communication / Power Supply Control Unit (Power Line Communication Unit)
43 Sub power switch (switch part)
44 Buzzer (Abnormality notification unit)
51 Circuit Module 52 Switching Power Supply 61 Main IC
62 AFE ・ IC
64 Coupler 91 Rectifier circuit 92, 93 Electrolytic capacitor 94 Transformer

Claims (6)

A power supply control device for controlling power supply from a power line to a power supply device,
A power line communication unit that communicates with other devices via the power line;
A switch unit interposed between the power line and the power supply device, and for switching on and off the power supply,
The power line communication unit detects the voltage of the power line and controls the operation of the switch unit based on the detection result.   The power supply control device according to claim 1, wherein the power line communication unit turns off the switch unit when detecting a different voltage different from a predetermined reference voltage.   The power supply control device according to claim 2, further comprising an abnormality notifying unit that notifies an operator of the abnormality of the power supply when the power line communication unit detects the different voltage.   The power line communication unit notifies the abnormality of the power supply to the other device via the power line when the power line communication unit detects the different voltage. Item 4. The power supply control device according to Item 3.   The power supply control device according to any one of claims 1 to 4, wherein the power line communication unit is interposed between the power line and the power supply device, and relays power from the power line.   An electronic device comprising the power supply control device according to any one of claims 1 to 5.

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