JP2008148062A - Filter control circuit, power supply tap, power receptacle, power extension cable, and filter control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filter control circuit which reduces the influence of noise which becomes hindrance for performing communication using a power line and furthermore, in which a communication signal for performing the communication using the power line is not filtered by a noise filter. <P>SOLUTION: The filter control circuit is provided with: signal detection parts 4, 4a, 4b, 4c which detect a PLC communication signal for an electronic device to perform the communication using the power line and switching parts 6, 6a, 6b which bypass noise filters 5, 5a, 5b to switch switches 61, 61a, 61b so that the power line is connected with the electronic device when the signal detection parts 4, 4a, 4b, 4c detect presence of the PLC communication signal and switch the switches 61, 61a, 61b so that the noise filters 5, 5a, 5b, the power line and the electronic device are connected to one another when the signal detection parts 4, 4a, 4b, 4c do not detect the presence of the PLC communication signal. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  In recent years, personal computers and peripheral devices of personal computers have been equipped with communication functions. By connecting to a communication network, each electrical device can communicate with each other by communicating with each other. The need to share information is increasing.

  As a technique for constructing the communication network, there are generally used a communication method for performing communication between electrical devices by using wireless and a method for performing communication between electrical devices by using wired communication.

  Specifically, wireless LAN (Local Area Network), Bluetooth (registered trademark), UWB (Ultra Wide Band), or the like is used as a communication method using radio.

  On the other hand, as a communication method using wired, there are a power line communication (PLC) method using a power line as a communication medium, a wired LAN, and the like. By using the PLC method, communication can be performed using an existing power line. For this reason, compared with the communication system using wired LAN, since it is not necessary to newly construct the wiring for constructing a communication network, the PLC system has the advantage that wiring construction cost is not necessary.

  However, in communication using the PLC method, noise generated by an electric device connected to the power line affects the communication using the PLC method.

  Specifically, a signal used for PLC communication is degraded by noise generated in a frequency band (for example, from 2 MHz to 30 MHz) used for PLC communication. As a result, communication throughput decreases or communication is disabled in the worst case. In view of this, various noise countermeasures have been proposed so as not to degrade signals used for PLC communication.

  For example, Patent Document 1 discloses a power line communication network system that connects a power line and a device that generates noise via a noise filter in the PLC system.

  FIG. 13 is a schematic diagram showing the configuration of the power line communication network system described in Patent Document 1. As shown in FIG. 13, a noise disturbance device 131 that generates noise and affects the power line is connected to a power line 133 via a noise filter (NF) 132.

  The noise filter 132 reduces noise by canceling the noise by generating a reverse-phase signal with the noise generated by the noise disturbance device 131. As a result, the power line communication network system described in Patent Document 1 can reduce the influence of noise generated by the noise disturbance device 131.

Patent Document 2 discloses a preamble detection device for detecting a preamble signal included in a signal used for PLC communication.
JP 2002-290288 A (released on October 4, 2002) Japanese Laid-Open Patent Publication No. 61-174849 (published August 6, 1986)

  However, in the power line communication network system described in Patent Document 1, when a device that performs PLC communication is connected to the power line via a noise filter, the noise filter filters frequency band components used for PLC communication. For this reason, there is a problem that communication cannot be performed with other PLC-type devices connected to the power line.

  In addition, it is difficult for a user who uses a device that communicates by the PLC method to recognize the presence of the noise filter and to prevent the information communicated by the device that communicates by the PLC method from passing through the noise filter. is there.

  Note that Patent Document 2 does not disclose or suggest a configuration for reducing noise so as not to deteriorate a signal used for PLC communication.

  The present invention has been made in view of the above problems, and its purpose is to reduce the influence of noise that hinders communication using a power line and to perform communication using the power line. It is intended to provide a filter control circuit, a power tap, a power outlet, a power extension cable, and a filter control method in which the communication signal is not filtered by a noise filter.

  In order to solve the above problems, the filter control circuit of the present invention is a filter control circuit for controlling a noise filter interposed between a power line and an electronic device, and the electronic device communicates using the power line. When the signal detection means for detecting a communication signal for performing communication and the signal detection means detect the presence of the communication signal, the power line and the electronic device are connected to bypass the noise filter. Switching means for switching the switch so that the noise filter, the power line, and the electronic device are connected when the signal detection means does not detect the presence of the communication signal. It is characterized by being.

  According to the above configuration, when the signal detection unit detects the presence of the communication signal, the switching unit switches the switch so that the power line and the electronic device are connected to bypass the noise filter. For this reason, the communication signal is not filtered by the noise filter. Therefore, communication performed by the electronic device using the power line is not blocked by the noise filter.

  According to the above configuration, when the signal detection unit does not detect the presence of the communication signal, the switching unit switches the switch so that the noise filter, the power line, and the electronic device are connected. . For this reason, when noise is emitted from the electronic device, the noise is filtered by the noise filter. Therefore, the communication of the electronic device connected to the power line is not delayed by the influence of the noise and the throughput is not lowered.

  Further, according to the above configuration, depending on whether or not the signal detection unit detects the communication signal, the switching unit bypasses the noise filter and connects the power line and the electronic device. The switch is switched so that the noise filter, the power line, and the electronic device are connected. Therefore, the user who uses the electronic device can connect the electronic device to the power line without recognizing the presence of the noise filter.

  Moreover, it is preferable that the signal detection means in the filter control circuit of the present invention detects the presence of the communication signal by detecting a preamble included in the communication signal.

  Thus, the signal detection means can be configured with a simple circuit configuration.

  Further, the communication signal in the filter control circuit of the present invention is a communication signal used for PLC communication, and the signal detection means detects a preamble included in the communication signal and demodulates the communication signal, Preferably, the presence of the communication signal is detected by determining whether or not the frame body portion of the demodulated communication signal is in a format used for the PLC communication.

  Thereby, the signal detecting means can detect the presence of the communication signal more reliably.

  The signal detection means in the filter control circuit of the present invention can be connected to a plurality of electronic devices, and is connected to the plurality of noise filters and the switching means corresponding to each of the plurality of electronic devices. Each of the plurality of switching means transmits the communication signal when the signal detection means detects the presence of the communication signal transmitted from each of the plurality of electronic devices connected to the signal detection means. Bypassing the noise filter corresponding to the electronic device and switching the switch so that the power line and the electronic device are connected, the signal detection means is transmitted from each of the plurality of connected electronic devices. When the presence of the communication signal is not detected, the noise filter corresponding to the electronic device that does not transmit the communication signal and It is preferred that the serial power lines and the electronic device switches the switch to be connected.

  Accordingly, the signal detection unit can detect each of the communication signals transmitted from the plurality of electronic devices without erroneous detection, and can control the plurality of noise filters. For this reason, it is possible to connect to a plurality of the electronic devices by one signal detection means, detect the communication signal transmitted from each of the plurality of electronic devices, and correspond to each of the plurality of electronic devices. A filter control circuit for controlling the plurality of switching means can be configured.

  A power strip according to the present invention includes the filter control circuit, and includes a plug that receives power from the power line, and an outlet that supplies the power to the electronic device.

  According to the above configuration, even if the electronic device connected to the outlet is an electronic device that communicates using a power line, the communication that the electronic device uses the power line is configured not to be blocked by a noise filter can do. Further, even when noise is emitted from the electronic device connected to the outlet, a power strip is configured so that communication of other electronic devices connected to the power line is not delayed by the influence of the noise or the throughput is not reduced. be able to. Furthermore, the said structure can comprise the power strip which can connect the said electronic device to the said electric power line, without the user using the said electronic device recognizing presence of the said noise filter.

  A power outlet according to the present invention includes the filter control circuit, and includes a terminal that receives power from the power line and an outlet that supplies the power to the electronic device.

  According to the above configuration, even if the electronic device connected to the outlet is an electronic device that communicates using a power line, the power outlet configured so that communication performed by the electronic device using the power line is not blocked by a noise filter can do. Moreover, even if noise is emitted from the electronic device connected to the outlet, a power outlet is configured in which communication of other electronic devices connected to the power line is not delayed by the influence of the noise or the throughput is not reduced. be able to. Furthermore, the said structure can comprise the power outlet which can connect the said electronic device to the said power line, without the user using the said electronic device recognizing presence of the said noise filter.

  A power supply extension cable of the present invention includes the filter control circuit, and includes a plug that receives power from the power line, and an outlet that supplies the power to the electronic device. The plug and the outlet are extension cables. It is connected by.

  According to the above configuration, even if the electronic device connected to the outlet is an electronic device that performs communication using a power line, the power extension cable that does not block communication performed by the electronic device using the power line by the noise filter. Can be configured. Moreover, even if noise is emitted from the electronic device connected to the outlet, a power outlet is configured in which communication of other electronic devices connected to the power line is not delayed by the influence of the noise or the throughput is not reduced. be able to. Furthermore, the said structure WHEREIN: The user who uses the said electronic device can comprise the power supply extension cable which can connect the said electronic device to the said power line, without recognizing presence of the said noise filter.

  The filter control method of the present invention is a filter control method for controlling a noise filter interposed between a power line and an electronic device, wherein the electronic device detects a communication signal for performing communication using the power line. When the communication signal is detected and the communication signal is detected, the switch is switched so that the power line and the electronic device are connected by bypassing the noise filter, but the presence of the communication signal is not detected. In some cases, the method includes a switch switching step of switching the switch so that the noise filter, the power line, and the electronic device are connected.

  According to the above configuration, there is provided a filter control method in which communication performed by the electronic device using the power line is not blocked by the noise filter even if the electronic device connected to the outlet is an electronic device that performs communication using the power line. Can be provided. In addition, even if noise is emitted from the electronic device connected to the outlet, a filter control method is provided in which communication of other electronic devices connected to the power line is not delayed by the influence of the noise and throughput is not reduced. can do. Furthermore, the said structure can provide the filter control method which can connect the said electronic device to the said power line, without the user using the said electronic device recognizing presence of the said noise filter.

  As described above, the present invention reduces the influence of noise that hinders communication using a power line, and further prevents a communication signal for performing communication using the power line from being filtered by a noise filter. The power tap, the power outlet, the power extension cable, and the filter control method can be provided.

  Hereinafter, the details of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

[Embodiment 1]
A power strip 1 including a filter control circuit according to the present embodiment will be described with reference to FIG.

  FIG. 1 is a schematic diagram illustrating a schematic configuration of a power strip including a filter control circuit according to the present embodiment.

  As shown in FIG. 1, the power strip 1 is electrically connected to a plug 2 and a power strip main body 7. The power tap main body 7 includes an outlet 3 and a filter control circuit 10. The plug 2 and the outlet 3 are electrically connected via the filter control circuit 10. The filter control circuit 10 includes a signal detection unit (signal detection unit) 4, a noise filter (NF) 5, and a switching unit (switching unit) 6. That is, the plug 2, the outlet 3, the signal detection unit 4, the noise filter 5, and the switching unit 6 are electrically connected.

  The plug 2 is electrically connected to the noise filter 5 included in the filter control circuit 10 and the switching unit 6. Specifically, the plug 2 is connected to the terminal 62 of the switching unit 6 through the noise filter 5, and is connected to the terminal 63 of the switching unit 6 without bypassing (bypassing) the noise filter 5. ing.

  The plug 2 is inserted (connected) into, for example, an outlet (not shown) installed in a house or the like, so that power from a power line (not shown) is received through the outlet. . The power received by the plug 2 is supplied to an electrical device (not shown) connected to the outlet 3 via the filter control circuit 10 and the outlet 3.

  The outlet 3 is electrically connected to the signal detection unit 4 and the switching unit 6, and is connected to the switching unit 6 and a switch 61 described later. When a plug (not shown) of an electrical device is connected to the outlet 3, the power received by the plug 2 is supplied to the electrical device.

  The signal detection unit 4 is connected to the outlet 3 and the switch 61 of the switching unit 6, and the electric device connected to the outlet 3 can perform PLC communication (hereinafter abbreviated as PLC communication). In the case of an electrical device (hereinafter abbreviated as PLC communication device), the switching unit 6 is controlled based on a signal (hereinafter abbreviated as PLC communication signal) for performing PLC communication transmitted from the PLC communication device. Is. Details will be described later.

  The noise filter 5 is connected to the plug 2 and a terminal 62 that is one terminal of the switching unit 6. The noise filter 5 is a blocking filter for preventing (filtering) a component in a frequency band (for example, from 2 MHz to 30 MHz) used for PLC communication from leaking to a power line to which the plug 2 is connected.

  The switching unit 6 includes a switch 61, a terminal 62, and a terminal 63. The switch 61 is connected to the outlet 3 and the signal detection unit 4 as described above. The terminal 62 is connected to the noise filter 5 as described above. The terminal 63 is directly connected to the plug 2 as described above. That is, the terminal 62 is connected to the plug 2 via the noise filter 5, and the terminal 63 is connected to the plug 2 bypassing the noise filter 5.

  The switching unit 6 switches whether to bypass the noise filter 5 based on the detection result of whether the signal detection unit 4 has detected a PLC communication signal.

  That is, the switching unit 6 connects the switch 61 with the terminal 62 based on the detection result of the signal detection unit 4, thereby connecting the electric device having a plug (not shown) to the outlet 3 and the power line. Connection is made via a noise filter 5. Alternatively, the switching unit 6 connects the switch 61 with the terminal 63 to connect the electric device with the plug (not shown) connected to the outlet 3 and the power line, bypassing the noise filter 5. Switch.

  Next, referring to FIGS. 1, 2, and 3, when a PLC communication device (not shown) is connected to the outlet 3, and an electric device (PLC communication device) that cannot perform PLC communication with the outlet 3 The operation of the power strip 1 when an electrical device other than the above is connected will be described.

  FIG. 2 illustrates an example of the present embodiment, and is a schematic diagram illustrating a configuration of the power tap 1 when a PLC communication device is connected to the outlet 3.

  FIG. 3 is a flowchart illustrating a processing procedure when an electrical device is connected to the outlet 3 of the power tap 1.

  First, a case where a PLC communication device is connected to the power tap 1 shown in FIG. 1 will be described with reference to FIGS. 3 and 1.

  When the plug 2 is installed in a house or the like and connected to an outlet (not shown) connected to the power line, and a PLC communication device (not shown) is connected to the outlet 3, the plug 2, Electric power is supplied to the PLC communication device via the filter control circuit 10 and the outlet 3.

  When the power switch of the PLC communication device to which power is supplied is turned on (input), the PLC communication device performs PLC communication with another PLC communication device via the power line, etc. A general initial procedure is performed to execute PLC communication.

  At this time, a PLC communication signal is transmitted to the signal detection unit 4 from the PLC communication device connected to the outlet 3. When the signal detection unit 4 detects the PLC communication signal (S110), the signal detection unit 4 transmits a filter bypass signal, which is an instruction signal for switching the switch 61 to connect to the terminal 63, to the switching unit 6. The switching unit 6 operates to connect the switch 61 to the terminal 63 based on the filter bypass signal from the signal detection unit 4 (S120). As a result, the switch 61 and the terminal 63 are connected as shown in FIG.

  That is, the PLC communication device connected to the outlet 3 and the power line are connected by bypassing the noise filter 5.

  Next, a case where an electric device other than the PLC communication device is connected to the power tap 1 shown in FIG. 1 will be described.

  When the plug 2 is installed in a house or the like and connected to an outlet (not shown) connected to a power line, and an electrical device (not shown) other than the PLC communication device is connected to the outlet 3, the power line From the plug 2, the filter control circuit 10, and the outlet 3, electric power is supplied to electrical devices other than the PLC communication device. And the power supply of electric equipments other than the said PLC communication equipment is turned on.

  However, in S110, since the PLC communication signal is not transmitted from the electrical device other than the PLC communication device, the signal detection unit 4 does not detect the PLC communication signal. Therefore, the signal detection unit 4 transmits a filter connection signal, which is an instruction signal for switching the switch 61 to the terminal 62, to the switching unit 6 (S130). Thereby, the switch 61 is connected to the terminal 62 as shown in FIG. That is, the electric device other than the PLC communication device connected to the outlet 3 and the power line are connected via the noise filter 5.

  As described above, in the power strip 1 according to the present embodiment, the signal detection unit 4 detects whether or not the PLC communication signal is included in the input signal from the electrical device connected to the outlet 3, and the signal detection unit 4 is configured to switch whether the switching unit 6 bypasses the noise filter 5 based on the detection result of No. 4.

  This eliminates the need for the user who connects the electrical device to the outlet 3 to recognize the presence or absence of the noise filter 5, and the user selects the electrical device to be connected to the outlet 3 depending on the presence or absence of the noise filter 5. There is no need to respond.

  Further, when the electrical device connected to the outlet 3 is a PLC communication device, as described above, the noise filter 5 is bypassed, and the power line and the PLC communication device are connected. For this reason, the PLC communication signal transmitted from the PLC communication device is not filtered by the noise filter 5. That is, the PLC communication performed by the PLC communication device is not blocked by the noise filter 5.

  Furthermore, when the electric device connected to the outlet 3 is an electric device other than the PLC communication device, as described above, even if noise of a frequency for performing PLC communication is emitted from the electric device, The noise is filtered by the noise filter 5. For this reason, it is possible to prevent the noise from entering the power line. Therefore, the PLC communication device connected to the power line is not delayed by the influence of the noise, and the throughput is not lowered.

[Embodiment 2]
Next, the case where the filter control circuit 10 according to the present embodiment is applied to a power outlet will be described with reference to FIG.

  FIG. 4 is a schematic diagram showing the configuration of a power outlet including the filter control circuit according to the present embodiment. For convenience of explanation, members having the same functions as those shown in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIG. 4, in the power outlet 11, the terminal 12 and the power outlet main body 17 are electrically connected.

  The power outlet main body 17 includes an outlet 3 and a filter control circuit 10. The filter control circuit 10 includes a signal detection unit 4, a noise filter 5, and a switching unit 6. That is, the terminal 12 and the outlet 3 according to the first embodiment are electrically connected to the filter control circuit 10 according to the first embodiment.

  Specifically, the terminal 12 is electrically connected to each of the noise filter 5 included in the filter control circuit 10 and the switching unit 6, and the terminal 62 of the switching unit 6 is connected via the noise filter 5. And is connected to a terminal 63 of the switching unit 6 by bypassing the noise filter 5.

  The terminal 12 is a terminal for receiving power from a power line (not shown), and is connected to the power line (not shown) to receive power from the power line. Then, the power received by the terminal 12 is supplied to an electrical device (not shown) connected to the outlet 3 via the filter control circuit 10 and the outlet 3.

  Next, the operation of the power outlet 11 when a PLC communication device (not shown) is connected to the outlet 3 will be described.

  Terminal 12 is connected to a power line (not shown), and a PLC communication device is connected to outlet 3. When the power switch is turned on, the PLC communication device connected to the outlet 3 performs an initial procedure for communicating with another PLC communication device, and performs PLC communication with the other PLC communication device.

  Similarly to the first embodiment, when the signal detection unit 4 detects the PLC communication signal included in the input signal transmitted from the PLC communication device connected to the outlet 3, the switch 61 is connected to the switch 61 with respect to the switch 61. A filter bypass signal for switching so as to be connected to 63 is transmitted.

  The switching unit 6 operates to connect the switch 61 to the terminal 63 based on the filter bypass signal from the signal detection unit 4. That is, the switching unit 6 switches the switch 61 so as to bypass the noise filter 5.

  Next, the operation of the power outlet 11 when an electrical device other than the PLC communication device is connected to the outlet 3 will be described.

  The terminal 12 is connected to a power line (not shown), and an electrical device other than the PLC communication device is connected to the outlet 3. The electrical device connected to the outlet 3 is turned on.

  However, as described above, since the PLC communication signal is not transmitted from the electric device, the signal detection unit 4 does not detect the PLC communication signal. For this reason, the signal detection unit 4 transmits a filter connection signal for connecting the switch 61 to the terminal 62 to the switching unit 6.

  Thereby, the switch 61 is connected to the terminal 62 as shown in FIG. That is, the electric device other than the PLC communication device connected to the outlet 3 and the power line are connected via the noise filter 5.

  Since the flowchart representing the processing procedure in the power outlet 11 is the same as that described in the first embodiment and FIG. 3, the description thereof is omitted in the present embodiment.

  As described above, the power outlet 11 detects whether or not the PLC communication signal is included in the input signal from the electrical device connected to the outlet 3, and based on the detection result of the signal detector 4. Thus, the switching unit 6 switches whether to bypass the noise filter 5. For this reason, when the electrical device connected to the outlet 3 is a PLC communication device, the PLC communication device and the power line are connected by bypassing the noise filter 5 (without the noise filter 5 interposed). Thus, the PLC communication is not blocked by the noise filter 5.

  When the electrical device connected to the outlet 3 is an electrical device other than the PLC communication device, the PLC communication device and the power line are connected via the noise filter 5 (without bypassing). Thus, the noise generated by the electric device is filtered. Therefore, the PLC communication device connected to the power line is not delayed by the influence of the noise, and the throughput is not lowered.

  Further, as described above, in the power outlet 11, the signal detection unit 4 detects whether or not the PLC communication signal is included in the input signal from the electric device connected to the outlet 3, and the detection result of the signal detection unit 4 is detected. Based on the above, the switching unit 6 switches whether to bypass the noise filter 5 or not. For this reason, it is not necessary for the user who connects the electrical device to the outlet 3 to recognize the presence or absence of the noise filter 5, and the user selects the electrical device to be connected to the outlet 3 depending on the presence or absence of the noise filter 5. There is no need to respond.

[Embodiment 3]
In the first embodiment, the power strip has been described. In the second embodiment, the power outlet has been described. Next, in this embodiment, a case where the filter control circuit 10 is applied to a power supply extension cable will be described.

  FIG. 5 is a schematic diagram showing the configuration of the power extension cable 21 including the filter control circuit according to the present embodiment.

  As shown in FIG. 5, in the power extension cable 21, the plug 2 according to the first embodiment and the power extension cable main body 27 are electrically connected via the extension cable 22.

The power extension cable body 27 includes the outlet 3 and the filter control circuit 10. The filter control circuit 10 includes a signal detection unit 4, a noise filter 5, and a switching unit 6.
That is, the plug 2 and the outlet 3 are electrically connected to the filter control circuit 10 according to the first and second embodiments via the extension cable 22.

  Specifically, the plug 2 is electrically connected to each of the noise filter 5 included in the filter control circuit 10 and the switching unit 6 via the extension cable 22, and is connected via the noise filter 5. It is connected to the terminal 62 of the switching unit 6, and is connected to the terminal 63 of the switching unit 6, bypassing the noise filter 5.

  As in the first embodiment, the plug 2 is installed in a house or the like and connected to an outlet (not shown) connected to a power line, and a PLC communication device (not shown) is connected to the outlet 3. When the power switch of the PLC communication device is turned on, a PLC communication signal is transmitted from the PLC communication device to the signal detection unit 4.

  And the signal detection part 4 will transmit the filter bypass signal which switches the switch 61 so that it may connect with the terminal 63 with respect to the switch part 6, if a PLC communication signal is detected from the PLC communication apparatus connected to the outlet socket 3. . As a result, the switching unit 6 operates to connect the switch 61 to the terminal 63 based on the filter bypass signal from the signal detection unit 4. That is, the switching unit 6 switches the switch 61 so as to bypass the noise filter 5.

  Also, when the plug 2 is connected to a power line (not shown), an electrical device other than the PLC communication device is connected to the outlet 3, and power is supplied to the electrical device connected to the outlet 3, the switch is turned on. Is possible.

  However, as described above, since the PLC communication signal is not transmitted from the electric device, even if the switch of the electric device is turned on, the signal detection unit 4 does not detect the PLC communication signal. For this reason, the signal detection unit 4 transmits a filter connection signal for switching the switch 61 to the terminal 62 to the switching unit 6.

  Thereby, the switch 61 is connected to the terminal 62 as shown in FIG. That is, the electric device other than the PLC communication device connected to the outlet 3 and the power line are connected via the noise filter 5.

  Since the flowchart representing the processing procedure in the power extension cable 21 is the same as that described in the first embodiment and FIG. 3, the description thereof is omitted in the present embodiment.

  As described above, in the power extension cable 21, the signal detection unit 4 detects whether the PLC communication signal is included in the input signal from the electrical device connected to the outlet 3, and the detection result of the signal detection unit 4 is obtained. Based on this, the switching unit 6 switches whether to bypass the noise filter 5. For this reason, when the electrical device connected to the outlet 3 is a PLC communication device, the PLC communication device and the power line are connected by bypassing the noise filter 5, so that the PLC communication is a noise filter. 5 is not interrupted.

  When the electrical device connected to the outlet 3 is an electrical device other than the PLC communication device, the PLC communication device and the power line are connected via the noise filter 5, whereby the electrical device The noise generated by is filtered. Therefore, the PLC communication device connected to the power line is not delayed by the influence of the noise, and the throughput is not lowered.

  Further, as described above, the power extension cable 21 detects whether the signal detection unit 4 detects whether or not the PLC communication signal is included in the input signal from the electrical device connected to the outlet 3, and the signal detection unit 4 detects the power extension cable 21. Based on the result, the switching unit 6 switches whether or not to bypass the noise filter 5.

  For this reason, it is not necessary for the user who connects the electrical device to the outlet 3 to recognize the presence or absence of the noise filter 5, and the user selects the electrical device to be connected to the outlet 3 depending on the presence or absence of the noise filter 5. There is no need to respond.

  In the present embodiment, the filter control circuit 10 has been described as being formed inside the power supply extension cable body 27. However, the filter control circuit 10 can be placed inside either the plug 2 or the outlet 3. It may be formed.

[Embodiment 4]
In the first embodiment, the power strip has been described. In the second embodiment, the power outlet has been described. In the third embodiment, the power extension cable has been described. Next, in the present embodiment, a case where the filter control circuit 10 is applied to a power strip provided with a plurality of outlets will be described.

  FIG. 6A is a schematic diagram illustrating an example of a power strip including the filter control circuit according to the present embodiment. FIG. 6B is a schematic diagram showing the appearance of the power tap 30 according to the present embodiment.

  As shown in FIG. 6A, the power strip 30 includes a plug 2 and a power strip body 31, and the plug 2 and the power strip body 31 are electrically connected by an extension cable 22. The power tap main body 31 includes filter control circuits 10a and 10b and a plurality of outlets 3a and 3b. The plug 2 and the extension cable 22 are the same as the plug 2 and the extension cable 22 described in the first embodiment.

  The filter control circuits 10a and 10b are connected to correspond to the outlets 3a and 3b, respectively. The filter control circuit 10a includes a signal detection unit 4a, a noise filter 5a, and a switching unit 6a. The filter control circuit 10b includes a signal detection unit 4b, a noise filter 5b, and a switching unit 6b.

  The outlets 3a and 3b correspond to the outlet 3, the signal detection units 4a and 4b correspond to the signal detection unit 4, the noise filters 5a and 5b correspond to the noise filter 5, and the switching units 6a and 6b correspond to the switching unit 6. To do.

  That is, when a plug (not shown) of an electrical device is connected to the outlets 3a and 3b, the power received by the plug 2 is supplied to the electrical device.

  And the signal detection parts 4a and 4b detect the PLC communication signal contained in the input signal from the electric equipment connected to the outlets 3a and 3b, respectively, and control the switching parts 6a and 6b based on the PLC communication signal. Is for.

  The noise filters 5a and 5b are blocking filters that filter components in a frequency band (for example, from 2 MHz to 30 MHz) used for PLC communication.

  The switching units 6a and 6b are configured to switch whether or not the noise filters 5a and 5b are bypassed based on the detection results of whether or not the signal detection units 4a and 4b have detected PLC communication signals, respectively.

  The switching unit 6a includes a switch 61a, a terminal 62a, and a terminal 63a. The switch 61a is connected to the outlet 3a and the signal detection unit 4a. The terminal 62a is connected to the noise filter 5a. The terminal 63a is directly connected to the plug 2. That is, the terminal 62a is connected to the plug 2 via the noise filter 5a, and the terminal 63a is connected to the plug 2 bypassing the noise filter 5a.

  The switching unit 6b has a switch 61b, a terminal 62b, and a terminal 63b. The switch 61b is connected to the outlet 3b and the signal detection unit 4b. The terminal 62b is connected to the noise filter 5b. The terminal 63b is directly connected to the plug 2. That is, the terminal 62b is connected to the plug 2 via the noise filter 5b, and the terminal 63b is connected to the plug 2 bypassing the noise filter 5b.

  The filter control circuit 10a when a PLC communication device (not shown) is connected to the outlets 3a and 3b, and when an electrical device (not shown) other than the PLC communication device is connected to the outlets 3a and 3b, Since each operation of 10b is the same as that of the filter control circuit 10 described above, description thereof is omitted in the present embodiment.

  Moreover, although each of the signal detection units 4a and 4b has been described as being connected in correspondence with each of the outlets 3a and 3b, the PLC communication from the PLC communication device connected to each of the outlets 3a and 3b. If the signal can be detected and each of the switching units 6a and 6b corresponding to each of the outlets 3a and 3b can be controlled, the signal detecting unit may be constituted by one. Specific examples will be described later.

  FIG. 7 is a schematic diagram illustrating an outline of an example of a power strip including the filter control circuit according to the present embodiment.

  As shown in FIG. 7, the power strip 32 includes a plug 2 and a power strip body 33, and the plug 2 and the power strip body 33 are electrically connected.

  The power tap main body 33 includes outlets 3a and 3b and a filter control circuit 15, and the outlets 3a and 3b and the filter control circuit 15 are electrically connected.

  The filter control circuit 15 includes a signal detection unit 4c, noise filters 5a and 5b, and switching units 6a and 6b.

  The signal detector 4c is electrically connected to each of the outlets 3a and 3b, and is also electrically connected to each of the switches 61a and 61b. The signal detection unit 4c transmits a filter bypass signal or a filter connection signal to the switching units 6a and 6b based on the detection result of whether or not the PLC communication signal is included in the input signals connected to the outlets 3a and 3b. .

  When detecting that the PLC communication signal is included in the input signal transmitted from the electrical device connected to the outlet 3a, the signal detection unit 4c connects the switch 61a to the terminal 63a for the switching unit 6a. A filter bypass signal for switching is transmitted. As a result, the switching unit 6a operates to connect the switch 61a to the terminal 63a.

  In addition, when the signal detection unit 4c does not detect the PLC communication signal from the input signal transmitted from the electric device connected to the outlet 3a, the signal detection unit 4c switches the switching unit 6a to connect the switch 61a to the terminal 62a. Send filter connection signal. As a result, the switching unit 6a operates to connect the switch 61a to the terminal 62a.

  Furthermore, when the signal detection unit 4c detects that the PLC communication signal is included in the input signal transmitted from the electrical device connected to the outlet 3b, the switch 61b is connected to the terminal 63b for the switching unit 6b. A filter bypass signal for switching is transmitted. As a result, the switching unit 6b operates to connect the switch 61b to the terminal 63b.

  Further, when the signal detection unit 4c does not detect the PLC communication signal from the input signal transmitted from the electric device connected to the outlet 3b, the signal detection unit 4c switches the switching unit 6b to connect the switch 61b to the terminal 62b. Send filter connection signal. As a result, the switching unit 6b operates to connect the switch 61b to the terminal 62b.

  Furthermore, although each of the power strip 30 and the power strip 32 has been described as having two outlets, the number of outlets is not limited to two, and may be three or more. It may be included.

  Further, each of the noise filters 5, 5a, 5b has been described as a blocking filter for filtering a component of a frequency band (for example, from 2 MHz to 30 MHz) used for PLC communication. For example, the noise filter 5 includes the above-described blocking filter, A low-pass filter or a high-pass filter that filters components in a frequency band different from that of the blocking filter may be included.

  With the above configuration, it is also possible to suppress the influence of radiation noise or the like that appears outside the frequency band used for PLC communication (for example, from 2 MHz to 30 MHz).

  Although the initial state of each of the switches 61, 61a, 61b included in each of the switching units 6, 6a, 6b has not been specifically described, power is supplied to the electrical equipment connected to the outlets 3, 3a, 3b. I can do it. Further, each of the switching units 6, 6 a, 6 b does not leak the signal from the power line and other outlets (not shown) connected to the power line to the signal detection units 4, 4 a, 4 b, and the signal is sufficient It is more desirable that the signal detectors 4, 4 a, 4 b are not erroneously detected by being attenuated.

  Moreover, although each of the signal detection part 4, 4a, 4b concerning Embodiment 1-4 demonstrated the example which detects the PLC communication signal from the electric equipment connected to each of the outlets 3, 3a, 3b, For example, each of the signal detection units 4, 4a, 4b may be configured such that each of the switching units 6, 6a, 6b switches the switch by detecting the preamble of the PLC communication signal.

  As described above, the power taps 30 and 32 are detected by the signal detection units 4a, 4b, or 4c to detect whether or not the PLC communication signal is included in the input signal from the electrical device connected to the outlets 3a and 3b. Based on the detection result of the detection unit 4a, 4b, or 4c, the switching unit 6a, 6b switches whether to bypass the noise filters 5a, 5b.

  For this reason, when the electrical device connected to the outlets 3a and 3b is a PLC communication device, the PLC communication device and the power line bypass the noise filters 5a and 5b (the noise filter 5 is not interposed). By connecting, PLC communication is not interrupted by the noise filters 5a and 5b.

  When the electrical device connected to the outlets 3a and 3b is an electrical device other than the PLC communication device, the PLC communication device and the power line are interposed by noise filters 5a and 5b (without bypassing). ) By being connected, the noise generated by the electrical device is filtered. Therefore, the PLC communication device connected to the power line is not delayed by the influence of the noise, and the throughput is not lowered.

  Furthermore, as described above, the power taps 30 and 32 are detected by the signal detectors 4a, 4b, or 4c as to whether or not the PLC communication signal is included in the input signal from the electrical equipment connected to the outlets 3a and 3b. Based on the detection result of the signal detection unit 4a, 4b or 4c, the switching unit 6a, 6b switches whether to bypass the noise filters 5a, 5b.

  For this reason, it is not necessary for the user who connects the electrical equipment to the outlets 3a and 3b to recognize the presence or absence of the noise filters 5a and 5b, and the connection to the outlets 3a and 3b is performed depending on the presence or absence of the noise filters 5a and 5b. There is no need for the user to select an electrical device.

[Signal processing method of filter control circuit]
Next, a signal processing method performed in the filter control circuits 10 and 15 will be described with reference to FIGS. In particular, the signal processing methods of the signal detection units 4, 4a, 4b and the switching units 6, 6a, 6b included in the filter control circuits 10, 15 will be described.

  First, the configuration of the PLC communication signal used in the first to fourth embodiments will be described with reference to FIG.

  FIG. 8 is a schematic diagram showing the configuration of the PLC communication signal.

  The PLC communication signal 50 has a configuration as shown in FIG. 8 and can have the same configuration as that of a generally used PLC communication signal.

  As shown in FIG. 8, the PLC communication signal 50 includes a preamble 52, a header 54, a payload 56, an FCS (Frame Check Sequence) 58, and the like.

  The preamble 52 is located at the head of the PLC communication signal 50, and is used to synchronize the PLC communication signal 50 with other PLC communication signals, signals inside the PLC communication device, and the like.

  The header 54 is for demodulating the payload 56, and stores information for demodulating the payload 56 and the like. The payload 56 stores a data body transmitted by PLC communication. The FCS 58 is used for detecting an error included in the demodulated payload 56. In the present embodiment, the header 54, payload 56, and FCS 58 subsequent to the preamble 52 are referred to as the frame body portion 51.

  Next, a method of detecting the PLC communication signal by the signal detection units 4, 4a, 4b will be described with reference to FIGS.

  FIG. 9 is a block diagram showing an outline of the configuration of the signal detection units 4, 4a, 4b and the switching units 6, 6a, 6b.

  FIG. 10 is a flowchart showing the signal processing flow of the signal detectors 4, 4a, 4b and the switching units 6, 6a, 6b.

  As shown in FIG. 9, the signal detection units 4, 4 a, 4 b include a signal detection unit 41, a preamble comparison unit 42, a frame format determination unit 43, and an instruction signal transmission unit 44. The switching units 6, 6a, 6b include a signal receiving unit 65, a switch switching unit 66, and switches 61, 61a, 61b.

  The signal detection unit 41 detects an input signal input from an electric device connected to the outlets 3, 3a, 3b. The signal detection unit 41 transmits the input signal to the preamble comparison unit 42.

  The preamble comparison unit 42 receives the input signal transmitted from the signal detection unit 41, and performs pattern comparison to determine whether the received input signal includes the preamble 52 used for PLC communication. If the pattern of the preamble 52 is included in the pattern of the input signal, a preamble match signal indicating a comparison result that matches the pattern is transmitted to the frame format determination unit 43. If the pattern of the preamble 52 is not included in the input signal pattern, a preamble mismatch signal indicating the comparison result of the pattern mismatch is transmitted to the instruction signal transmitter 44.

  In the preamble comparison unit 42, a preamble pattern used for a PLC communication signal is registered in advance. The preamble pattern registered in the preamble comparison unit 42 is not particularly limited as long as it can detect a commonly used preamble.

  The frame format determination unit 43 demodulates the frame body portion 51 of the input signal, determines whether or not the demodulated frame body portion 51 is the frame format of the PLC communication signal, and matches the frame format that is the determination result A signal or a frame format mismatch signal is transmitted to the instruction signal transmission unit 44.

  In the frame format determination unit 43, a frame format used for the PLC communication signal is registered in advance, and the registered frame format is compared with the frame body unit 51. The frame format registered in the frame format determination unit 43 is not particularly limited as long as it can detect a generally used frame format.

  When the frame format determination unit 43 determines that the frame body unit 51 has a pre-registered frame format, the frame format determination unit 43 determines that the input signal is a PLC communication signal, and determines the frame format match signal as a determination result. Transmit to the instruction signal transmitter 44.

  If the frame format determining unit 43 determines that the frame body unit 51 is not a pre-registered frame format, the frame format determining unit 43 determines that the input signal is not a PLC communication signal, and outputs a frame format mismatch signal as a determination result. Transmit to the instruction signal transmitter 44.

  As described above, by determining whether or not the frame body portion 51 of the input signal has a frame format registered in advance in the frame format determining portion 43, it is possible to coincide with the preamble pattern registered in the preamble 52 by chance. Even if a matched signal (or noise) is input, it is possible to reliably determine whether the signal is a PLC communication signal.

  The instruction signal transmission unit 44 transmits an instruction signal to the switching units 6, 6 a, 6 b based on the comparison result of the preamble comparison unit 42 or the determination result of the frame format determination unit 43.

  When the frame format match signal is transmitted from the frame format determination unit 43, the instruction signal transmission unit 44 connects the filter bypass signal to the switching units 6, 6a to connect the switches 61, 61a, 61b to the terminals 63, 63a, 63b. , 6b to the signal receiver 65.

  In addition, the instruction signal transmission unit 44 connects the switches 61, 61a, and 61b when a preamble mismatch signal is transmitted from the preamble comparison unit 42 or when a frame format mismatch signal is transmitted from the frame format determination unit 43. A filter connection signal is transmitted to the signal receiving unit 65 of the switching unit 6, 6a, 6b to connect to 62, 62a, 62b.

  The signal receiving unit 65 receives the filter bypass signal or the filter connection signal from the instruction signal transmission unit 44 and transmits the received filter bypass signal or the filter connection signal to the switch switching unit 66.

  The switch switching unit 66 switches the switches 61, 61a, 61b based on the filter bypass signal or the filter connection signal transmitted from the signal receiving unit 65.

  When a filter bypass signal for connecting the switches 61, 61a, 61b to the terminals 63, 63a, 63b is transmitted from the signal receiving unit 65, the switch switching unit 66 switches the switches 61, 61a, 61b to the terminals 63, Operate to connect to 63a and 63b. Further, when a filter connection signal for connecting the switches 61, 61a, 61b to the terminals 62, 62a, 62b is transmitted from the signal receiving unit 65, the switch switching unit 66 switches the switches 61, 61a, 61b to the terminals. It operates to connect with 62, 62a, 62b.

  Next, the flow of signal processing in the signal detection units 4, 4a, 4b and the switching units 6, 6a, 6b will be described with reference to FIG.

  When an input signal is input to the signal detectors 4, 4a, 4b, the signal detector 41 receives the input signal (S210). The signal pattern of the input signal received by the signal detection unit 41 is compared by the preamble comparison unit 42 with the preamble pattern used for PLC communication registered in advance in the preamble comparison unit 42 (S220).

  As a result of comparing the preamble pattern with the signal pattern of the input signal in S220, if the signal pattern matching the preamble pattern is not included in the input signal, a PLC communication device is connected by the preamble comparison unit 42. It is determined that it is not present (S240).

  The determination result is transmitted from the instruction signal transmitting unit 44 to the signal receiving unit 65 of the switching unit 6, 6a, 6b, and the switch switching unit 66 connects the switches 61, 61a, 61b to the terminals 62, 62a, 62b. (S280). That is, the switches 61, 61a, 61b are switched so as not to bypass the noise filters 5, 5a, 5b.

  As a result of comparing the preamble pattern and the signal pattern of the input signal in S220, if the input signal includes a signal pattern that matches the preamble pattern, the frame format determination unit 43 causes the frame in the input signal to be The signal corresponding to the body part 51 is demodulated (S250). Then, it is determined whether or not the demodulated frame body part 51 has a frame format registered in advance in the frame format determination part 43 (S255).

  In S255, when the frame format determination unit 43 determines that the demodulated frame body unit 51 is not a frame format registered in advance in the frame format determination unit 43, the frame format determination unit 43 determines that the input signal is It determines with it not being a PLC communication signal (S260). And the process of S280 mentioned above is performed.

  In S255, when the frame format determination unit 43 determines that the demodulated frame body unit 51 is a frame format registered in advance in the frame format determination unit 43, the frame format determination unit 43 It is determined that the input signal is a PLC communication signal (S265).

  The determination result is transmitted from the instruction signal transmitting unit 44 to the signal receiving unit 65 of the switching unit 6, 6a, 6b, and the switch 61, 61a, 61b is connected to the terminal 63, 63a, 63b by the switch switching unit 66 ( S270). That is, the switches 61, 61a, 61b are switched to bypass the noise filters 5, 5a, 5b.

  In the present embodiment, it is determined whether or not the signal corresponding to the frame body 51 is the frame format of the PLC communication signal, but it may be determined whether or not the header 54 is the format of the PLC communication signal. Further, by confirming that no error is included in the payload 56 using the FCS 58, the PLC communication signal may be identified and it may be determined whether or not the PLC communication device is connected.

  In addition, you may be the structure which determines that it is a PLC communication signal by methods other than the above.

  In FIG. 9, the signal detection units 4, 4 a, 4 b may be configured without the frame format determination unit 43. That is, the preamble comparison unit 42 can determine whether or not the signal is a PLC communication signal only by comparing the preamble pattern registered in the preamble comparison unit 42 with the signal.

  As a method for detecting the preamble 52 of the signal by the preamble comparing unit 42, a commonly used method can be used in the present embodiment, for example, a preamble detecting device disclosed in Japanese Patent Application Laid-Open No. 61-174849, etc. Various methods can be used. Since each of the signal detection units 4, 4a, 4b is configured to detect the preamble 52 of the PLC communication signal, each of the signal detection units 4, 4a, 4b can be realized with a simple circuit configuration.

  The flow of signal processing of the signal detection units 4, 4 a, 4 b and the switching units 6, 6 a, 6 b when the frame format determination unit 43 is excluded will be described using FIG. 11.

  FIG. 11 is a flowchart showing the signal processing flow of the signal detection units 4, 4 a and 4 b and the switching units 6, 6 a and 6 b, and excluding the frame format determination unit 43.

  As shown in FIG. 11, when a signal is input to the signal detector 4, the signal detector 41 detects the input signal (S210). The input signal detected by the signal detector 41 is compared with a preamble pattern used for PLC communication registered in the preamble comparator 42 in advance by the preamble comparator 42 (S220).

  As a result, if the preamble pattern matches the signal pattern of the input signal, the preamble comparison unit 42 determines that the PLC communication device is connected (S230). The determination result is transmitted from the instruction signal transmitting unit 44 to the signal receiving unit 65 of the switching unit 6, 6a, 6b, and the switch 61, 61a, 61b is connected to the terminal 63, 63a, 63b by the switch switching unit 66 ( S270). That is, the switches 61, 61a, 61b are switched to bypass the noise filters 5, 5a, 5b.

  In S220, if the preamble pattern and the signal pattern of the input signal are not matched as a result of comparison, the preamble comparator 42 determines that the PLC communication device is not connected (S240). The determination result is transmitted from the instruction signal transmitting unit 44 to the signal receiving unit 65 of the switching unit 6, 6a, 6b, and the switch 61, 61a, 61b is connected to the terminal 62, 62a, 62b by the switch switching unit 66 ( S280). That is, the switches 61, 61a, 61b are switched so as not to bypass the noise filters 5, 5a, 5b.

  Next, a method in which the signal detection unit 4c of the filter control circuit 15 included in the power tap 32 detects the PLC communication signal will be described with reference to FIG.

  FIG. 12 is a block diagram illustrating an outline of an example of the configuration of the signal detection unit 4c and the switching units 6a and 6b.

  As shown in FIG. 12, the signal detection unit 4c includes signal detection units 41a and 41b, a preamble comparison unit 42, a frame format determination unit 43, and an instruction signal transmission unit 44c. The switching unit 6a includes a signal receiving unit 65, a switch switching unit 66, and a switch 61a. The switching unit 6b includes a signal receiving unit 65, a switch switching unit 66, and a switch 61b.

  The signal detection unit 41a detects an input signal input from an electric device connected to the outlet 3a. The signal detection unit 41a transmits the detected input signal to the preamble comparison unit 42, and transmits a connection signal for notifying the signal transmission unit 44c that the input signal has been detected from the electrical device connected to the outlet 3a. Send.

  Moreover, the signal detection part 41b detects the input signal input from the electric equipment connected to the outlet 3b. The signal detection unit 41b transmits the detected input signal to the preamble comparison unit 42, and transmits a connection signal for notifying the signal transmission unit 44c that the input signal has been detected from the electrical device connected to the outlet 3b. Send.

  The preamble comparison unit 42 receives the input signal transmitted from the signal detection unit 41a or the signal detection unit 41b, and performs the above-described processing. That is, a pattern comparison is performed to determine whether or not the received input signal includes a preamble 52 used for PLC communication, and the comparison result is transmitted to the frame format determination unit 43 or the instruction signal transmission unit 44c based on the comparison result. .

  The frame format determination unit 43 receives the comparison result from the preamble comparison unit 42, performs the above-described processing, and transmits the above-described determination result to the instruction signal transmission unit 44a.

  The instruction signal transmission unit 44c transmits a filter bypass signal or a filter connection signal indicating the instruction signal to the switching units 6a and 6b based on the determination result of the preamble comparison unit 42 or the frame format determination unit 43.

  In addition, by receiving the connection signal transmitted from the signal detection unit 41a and the signal detection unit 41b, the determination result transmitted from the preamble comparison unit 42 or the frame format determination unit 43 is connected to the outlet 3a. Or a signal from an electrical device connected to the outlet 3b. That is, the instruction signal transmission unit 44c receives the connection signal transmitted from the signal detection unit 41a and immediately after receiving the connection signal transmitted from the preamble comparison unit 42 or the frame format determination unit 43, the determination result is the electric device connected to the outlet 3a. It is determined that the signal is from. In addition, the determination result received from the preamble comparison unit 42 or the frame format determination unit 43 immediately after receiving the connection signal transmitted from the signal detection unit 41b is determined to be a signal from an electrical device connected to the outlet 3b. To do.

  As described above, the signal detection unit 4c determines whether the input signal from the electric device connected to the outlet 3a or the input signal from the electric device connected to the outlet 3b is incorrect. There is no detection.

  When the instruction signal transmission unit 44c determines that the determination result transmitted from the preamble comparison unit 42 or the frame format determination unit 43 is a signal from an electrical device connected to the outlet 3a, the instruction signal transmission unit 44c switches to the switching unit 6a. A filter bypass signal for switching the switch 61a or a filter connection signal is transmitted to the signal receiving unit 65 included in the signal.

  When the instruction signal transmission unit 44c determines that the determination result transmitted from the preamble comparison unit 42 or the frame format determination unit 43 is a signal from an electrical device connected to the outlet 3b, the instruction signal transmission unit 44c switches to the switching unit 6b. A filter bypass signal for switching the switch 61b or a filter connection signal is transmitted to the signal receiving unit 65 included in the signal.

  Further, the signal detection unit 4c may have a configuration in which the frame format determination unit 43 is excluded, similar to the signal detection units 4, 4a, and 4b. Since the signal processing of the signal detection unit 4c when the frame format determination unit 43 is excluded is the same as the description of the signal detection units 4, 4a, and 4b described above, description thereof is omitted.

  As described above, the embodiments of the present invention have been described. However, it should be considered that the embodiments and modifications disclosed this time are illustrative and not restrictive in all respects. The scope of the present invention is defined by the terms of the claims, and includes meanings equivalent to the terms of the claims and all modifications within the scope.

The present invention can also be expressed as follows.
(1) A plug for receiving power from a power line, an outlet for supplying the power, signal detection means for detecting a signal from a device connected to the outlet, and a switch according to the detection result of the signal detection means Switching means for switching between, and a filter for removing a predetermined frequency component superimposed on the power between the plug and the switching means, and the switching means sends the signal to the outlet based on the detection result. When the communication signal is from a connected device, the switch is switched to connect the power line and the device without the filter, and the signal is communicated from the device connected to the outlet. When the signal is not a signal, the switch is switched to connect the power line and the device so as to interpose the filter. Source tap.
(2) a terminal for receiving power from a power line, an outlet for supplying the power, signal detection means for detecting a signal from a device connected to the outlet, and a switch according to a detection result of the signal detection means And switching means for removing a predetermined frequency component superimposed on the power between the terminal and the switching means, and the switching means sends the signal to the outlet based on the detection result. When the communication signal is from a connected device, the switch is switched to connect the power line and the device without the filter, and the signal is communicated from the device connected to the outlet. A power supply characterized by switching the switch so as to connect the power line and the device so as to interpose the filter when it is not a signal Outlet.
(3) a plug for receiving power from a power line, an outlet for supplying the power, a signal detection means for detecting a signal from a device connected to the outlet, and a switch according to a detection result of the signal detection means Switching means for switching between, and a filter for removing a predetermined frequency component superimposed on the power between the plug and the switching means, and the switching means sends the signal to the outlet based on the detection result. When the communication signal is from a connected device, the switch is switched to connect the power line and the device without the filter, and the signal is communicated from the device connected to the outlet. When the signal is not a signal, the switch is switched to connect the power line and the device so as to interpose the filter. Source extension cable.
(4) A filter control circuit used for power line communication, a signal detection circuit having a function of detecting a signal superimposed on the power line, a filter for removing a predetermined frequency component, and a detection result of the signal detection circuit And a switching circuit for switching whether or not to cause the filter to function based on the filter control circuit.
(5) The power strip according to (1), wherein the signal detection unit detects whether or not the signal is a signal of power line carrier communication from a device connected to the outlet.
(6) The power outlet according to (2), wherein the signal detection unit detects whether or not the signal is a signal of power line carrier communication from a device connected to the outlet.
(7) The power extension cable according to (3), wherein the signal detection unit detects whether or not the signal is a signal of power line carrier communication from a device connected to the outlet.
(8) The filter control circuit according to (4), wherein the signal detection circuit detects whether or not the signal is a signal of power line carrier communication.

  According to the present invention, a filter control circuit and a power strip that reduce the influence of noise that hinders communication using a power line, and that a communication signal for performing communication using the power line is not filtered by a noise filter. A power outlet, a power extension cable, and a filter control method.

It is a schematic diagram which shows schematic structure of the power tap containing the filter control circuit which concerns on one Embodiment of this invention. It is a schematic diagram which shows schematic structure of the power strip containing the filter control circuit which concerns on one Embodiment of this invention, and shows a power strip when a PLC communication apparatus is connected. It is a flowchart showing the procedure of the process of a filter control circuit when an electric equipment is connected to the power strip containing the filter control circuit of this invention. It is a schematic diagram which shows schematic structure of the power outlet including the filter control circuit which concerns on one Embodiment of this invention. It is a schematic diagram which shows schematic structure of the power supply extension cable containing the filter control circuit which concerns on one Embodiment of this invention. FIG. 6A is a schematic diagram showing a schematic configuration of a power strip including a filter control circuit according to an embodiment of the present invention, and FIG. 6B is a diagram of the power strip shown in FIG. It is a schematic diagram which shows an external appearance. It is a schematic diagram which shows schematic structure of the power tap containing the filter control circuit which concerns on one Embodiment of this invention. It is the schematic which shows an example of a structure of the PLC communication signal which the filter control circuit which concerns on this Embodiment detects. It is a block diagram which shows the outline of a structure of the signal detection part contained in the filter control circuit concerning this Embodiment, and a switching part. It is a flowchart which shows the flow of the signal processing of the signal detection part contained in the filter control circuit concerning this Embodiment, and a switching part. It is a flowchart which shows the flow of the signal processing of the signal detection part contained in the filter control circuit concerning this Embodiment, and a switching part, and shows the case where a frame format is excluded. It is a block diagram which shows the outline of a structure of the signal detection part contained in the filter control circuit concerning this Embodiment, and a switching part. It is the schematic which shows the structure of the conventional power line communication network system.

Explanation of symbols

1 Power Tap 2 Plug 3, 3a, 3b Outlet 4, 4a, 4b, 4c Signal Detection Unit (Signal Detection Means)
5, 5a, 5b Noise filter 6, 6a, 6b Switching section (switching means)
10, 10a, 10b Filter control circuit 11 Power outlet 12 Terminal 15 Filter control circuit 21 Power extension cable 22 Extension cable 50 PLC communication signal (communication signal)
51 Frame body 52 Preamble 61, 61a, 61b Switch

Claims (8)

A filter control circuit for controlling a noise filter interposed between a power line and an electronic device,
Signal detection means for detecting a communication signal for the electronic device to communicate using the power line; and
When the signal detection means detects the presence of the communication signal, the switch is switched so that the power line and the electronic device are connected, bypassing the noise filter, while the signal detection means is the communication signal. A filter control circuit comprising switching means for switching the switch so that the noise filter, the power line, and the electronic device are connected when the presence of the noise is not detected.   The filter control circuit according to claim 1, wherein the signal detection unit detects the presence of the communication signal by detecting a preamble included in the communication signal. The communication signal is a communication signal used for PLC communication,
The signal detection means detects a preamble included in the communication signal, demodulates the communication signal, and determines whether or not a frame body portion of the demodulated communication signal is a format used for the PLC communication. The filter control circuit according to claim 1, wherein the presence of the communication signal is detected. The signal detection means can be connected to a plurality of electronic devices,
Connected to the plurality of noise filters and the switching means corresponding to each of the plurality of electronic devices,
Each of the plurality of switching means transmits the communication signal when the signal detection means detects the presence of the communication signal transmitted from each of the plurality of electronic devices connected to the signal detection means. While switching the switch so that the power line and the electronic device are connected, bypassing the noise filter corresponding to the electronic device,
When the signal detection means does not detect the presence of the communication signal transmitted from each of the plurality of connected electronic devices, the noise filter and the power line corresponding to the electronic device that does not transmit the communication signal The filter control circuit according to claim 1, wherein the switch is switched so that the electronic device is connected to the electronic device. Including the filter control circuit according to any one of claims 1 to 4,
A plug for receiving power from the power line;
An outlet for supplying the electric power to the electronic device;
A power strip characterized by comprising. Including the filter control circuit according to any one of claims 1 to 4,
A terminal for receiving power from the power line;
An outlet for supplying the electric power to the electronic device;
A power outlet characterized by comprising. Including the filter control circuit according to any one of claims 1 to 4,
A plug for receiving power from the power line;
An outlet for supplying the electric power to the electronic device;
With
A power extension cable, wherein the plug and the outlet are connected by an extension cable. A filter control method for controlling a noise filter interposed between a power line and an electronic device,
A communication signal detection step of detecting a communication signal for the electronic device to communicate using the power line;
When the communication signal is detected, the noise filter is bypassed and the switch is switched so that the power line and the electronic device are connected. On the other hand, when the presence of the communication signal is not detected, the noise filter And a switch switching step for switching the switch so that the power line and the electronic device are connected,
A filter control method comprising:

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