JP3051991U - Power display device and plug, plug adapter, power tap, AC adapter, and electric device provided with the power display device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a technique capable of preventing forgetting to remove a plug or mistaken disconnection when an electric device is plugged into an outlet and operated. SOLUTION: A plug terminal inserted into an outlet
(2, 3) and a display (6) for indicating that the plug terminal (2, 3) has been inserted into an outlet.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a technology capable of preventing a plug from being forgotten or mistakenly removed when an electric device is plugged into an outlet and operated.

[0002]

[Prior art]

 To use electrical equipment (all equipment that has a plug for plugging into an outlet; the same applies hereinafter), plug in the outlet and turn on the switch on the main unit side of the electrical equipment. However, it is preferable to remove the plug from the outlet after the use is completed. This is also to prevent accidents, especially when going out for a long time. It is also necessary to prevent accidental unplugging of electrical equipment while using it. For example, if you accidentally unplug the computer while using the computer and mistakenly connect it to the wrong device, data loss or hard disk failure may occur.

[0003]

[Problems to be solved by the invention]

 However, there are many cases where it is not possible to immediately recognize whether or not a plug is inserted in the current electrical equipment, or whether or not the electrical equipment is in use while the plug is inserted. Especially when the outlets are in the corners of the room and hidden behind furniture, or when there are many plugs in multiple outlets, determine which plug corresponds to which electrical device. It was extremely difficult to judge at a glance.

The present invention has been made in view of the above circumstances, and has as its object to prevent the user from forgetting to remove a plug or to mistakenly disconnect the plug when the plug of an electric device is operated by being plugged into an outlet. And a plug, a plug adapter, a power tap, an AC adapter, and an electric device provided with the power display device.

[0005]

[Means for Solving the Problems]

 In order to achieve the above object, the power supply display device according to the present invention and the plugs, plug adapters, power taps, AC adapters, and electric devices provided with the power supply display device are described in the section of the claims of utility model registration. This is as described in claims 1 to 25. That is, by providing the first display means for displaying the state of insertion of the plug of the electric device into the outlet, the state of insertion of the plug into the outlet can be easily confirmed by visually checking the display means. The display means may be one that appeals to hearing or one that appeals to vision.Either of them may be used.However, when the plug terminal is inserted into the outlet using a luminous body that appeals to vision, There is a configuration in which the luminous body is turned on. In this way, the lighting of the illuminator makes it possible to immediately recognize that the plug is inserted into the outlet even from a distance. Therefore, it is possible to effectively prevent the user from forgetting to remove the plug after the use of the electrical device. Here, the light-emitting body refers to all elements that emit light, such as an LED and a liquid crystal panel with a backlight.

In addition to the first display means for displaying the state of insertion of the plug of the electric device into the outlet, the second display means for displaying the power supply state from the plug to the electric apparatus is provided as the display means. With the additional provision, it is possible to immediately recognize whether or not the plugged-in electrical device is actually being used. Therefore, it is possible to prevent the plug of the electrical equipment being used from being accidentally pulled out. As a display mode of the display means, for example, a mode in which a light-emitting body is turned on can be cited. By making the emission colors of the first display means (light emitter) and the second display means (light emitter) different, it is possible to more clearly recognize whether or not the electric device is used. it can.

Further, the first display means and the second display means can be shared by the same light emitting body. As a result, the number of luminous bodies can be reduced, so that there is a cost advantage. As a method of controlling the luminous body, it is possible to recognize whether or not the electric device is used by making the luminous state of the luminous body different. For example, when the plug terminal is inserted into the outlet, the luminous body is turned on (an aspect of the first state), and when the electric device is turned on by turning on a switch or the like, the luminous body blinks. (An aspect of the second state). In this way, whether the illuminator is lit or blinking, or because of the difference in the cycle of blinking, it is merely that the plug is plugged into the outlet, the electrical equipment is actually in use. You can immediately recognize if there is. As another mode, when the plug terminal is inserted into the outlet, the light emitter is turned on in a first emission color, and when the electric device is turned on, the light emitter is turned on in a second emission color. Can be turned on. A typical example of such a light emitting body is a two-color light emitting LED.

[0008] Although the above description has been made merely by changing the lighting state of the light-emitting body, the following configuration is more effective. That is, the display device includes a luminous body that indicates that the plug terminal has been inserted into the outlet, and a display panel provided on the front surface of the luminous body. In the display panel, the plug terminal is connected. It is intended to provide a visual indication of the operating electrical equipment. For example, characters such as "PC" or "video" are printed on a display panel or a sticker is attached. Thereby, it is possible to immediately recognize which electric device is connected.

Further, in addition to the display panel, a second illuminant that indicates that a switch on the side of an electric device that is operated by connecting the plug terminal is operated, and a second illuminator provided on a front surface thereof. It is preferable that a display panel is provided, and a visual display is provided on the second display panel so that removal of the plug terminal can be prohibited. According to this, it is possible not only to immediately recognize which electrical device is connected, but also to display that the electrical device is actually used, and to prohibit disconnection of the plug terminal. Such a visual display makes it possible to reliably prevent the plug from being accidentally unplugged.

[0010] The new functions and configurations described so far have been described with respect to the power-supply display device, which is indispensable in terms of function. However, various types of product forms of the power-supply display device can be selected. There are elements. They are built into electrical equipment plugs, plug adapters, power strips, electrical equipment bodies, and power supply lines to electrical equipment.

A plug adapter is an adapter that is connected to a plug of an electric device, and has a plug terminal that is plugged into an outlet. Originally, even an electrical device that does not have a plug with a new feature can be provided with the same function by connecting such a plug adapter. Here, depending on the impedance of the electric equipment to which the plug adapter is connected, the luminous body may not emit light accurately due to the small current flowing. Therefore, the provision of the sensitivity adjusting mechanism for adjusting the sensitivity enables the light emitting body to emit light reliably even when the supplied current is minute.

When applied to a power strip, it is possible to immediately recognize that the plug terminal of the electric device has been inserted into the outlet of the power tap, and the electric device into which the plug is inserted is actually used now. You can immediately recognize whether or not. If the second display means is constituted by a luminous body provided in each of the plurality of outlets, it is possible to immediately visually recognize which electrical device is connected to which outlet and which is being used now. Can be.

[0013] The form of the external display by the second display means may be a frame-type display portion surrounding the periphery of the outlet, and the electric power related to which plug among the plugs inserted into the plurality of outlets. Since the device is directly displayed as to whether it is in use, it can be recognized more reliably.

[0014] The new function can be applied to an AC adapter. AC adapters are often used for electrical equipment that requires portability. For example, CD boombox, notebook PCs, word processors, digital cameras, etc. In addition, a display means for indicating that the plug terminal has been inserted into the outlet is provided in the middle or at an end of a power supply line (cord wire) connecting the main body of the electric device and the plug terminal, instead of the plug. Is also good. For example, a kotatsu has a switch in the middle of a code line, and a display panel is provided at the switch portion, and a visual display can be provided on the display panel so that the user can be careful not to forget to remove the plug terminal. If you forget to unplug a heating device such as a kotatsu or iron, you may cause a fire.If you display a warning that you forget to remove the plug, you will be able to recognize this fact and prevent a major accident. it can .

As a function of the novel power supply display device, a voltage detecting means for detecting a voltage drop may be provided, and a third display means for displaying that the voltage has dropped may be further provided. If a large current flows through the electrical equipment being used, the voltage will drop, and if it exceeds the rated value, the breaker will trip. Indicating that the voltage has dropped allows the user to be aware of the possibility of malfunction of the equipment or the possibility of the breaker tripping, thereby preventing a serious accident from occurring. . In the case where a plurality of display means are provided and these display means are formed of light-emitting members, if the light-emitting colors of the respective light-emitting members are different from each other, which light-emitting member is emitting light, that is, at present, Can immediately recognize the situation. In the case where a plurality of display means are used, if some of them are shared by the same light-emitting body, cost can be reduced. For example, the luminous body is switched from a lighting state to a blinking state, or the luminous color of the luminous body is switched.

Furthermore, if a breaker that cuts off the power supply line when the voltage drops is further provided in the plug, only the circuit of the electric device that should operate the breaker is cut off without cutting off the circuit of another electric device. It is preferable because it is possible.

The voltage detecting means for detecting the voltage drop can of course be provided in a plug adapter or a power tap. When used as a power tap, it is preferable to provide a display means for displaying the current or power level.

Other features and advantages of the present invention will become apparent from the following description of embodiments with reference to the drawings.

[0019]

[Embodiment of the invention]

 [First Embodiment of Plug] FIG. 1A shows a plug according to a first embodiment. The plug 1 includes a pair of plug terminals 2, 3, a cover member 4 for holding the plug terminals 2, 3, a cord wire 5 connected to the main body of the electric device, and a display unit 6. FIG. 1 (b) briefly explains the circuit configuration. A resistor 7 and an LED 8 are connected in parallel between plug terminals 2 and 3. When the plug 1 is inserted into the outlet 9, the LED 8 lights up, so that the display 6 indicates that the plug 1 is inserted into the outlet 9. Although the LED 8 is actually blinking at 50 Hz or 60 Hz, it is recognized as lit by human eyes.

[Second Embodiment of Plug] FIG. 2A shows a plug according to a second embodiment. The difference from the first embodiment is that a first display unit 10 and a second display unit 11 are provided. The first display unit 10 displays whether or not the plug 1 is plugged into the outlet 9. The display unit 11 displays whether or not the electric device is energized, for example, whether or not a switch on the electric device body is turned ON. In FIG. 2B, when the plug 1 is inserted into the outlet 9, the LED 8 is turned on and the first display unit 10 displays the LED. The detection circuit 13 detects whether the electric device is turned on, and is a closed circuit including the induction coil 28, the resistor 29, and the LED 12. When the electric device is turned on, a current flows through the code line 5, thereby generating an electromotive force in the induction coil 28, turning on the LED 12 and displaying it on the second display unit 11.

[Third Embodiment of Plug] The external appearance of a plug according to a third embodiment is the same as that of FIG. 1 and the number of display units 6 is one, but a two-color light emitting LED 15 is used as a light emitter. As shown in the circuit diagram of FIG. 3, the LED 15 has a red light emitting portion 15a and a green light emitting portion 15b, and is connected to a first semiconductor relay element 16 and a second semiconductor relay element 17, respectively. Further, protective resistors 14a and 14b are provided in series with the light emitting units 15a and 15b. The detection circuit 12 includes an induction coil 28, a rectifier circuit section 18, and an inverter 19, and the output of the rectifier circuit section 18 is directly connected to the base of the first semiconductor relay element 16 and the It is connected to the base of semiconductor relay element 17. According to this, when the plug 1 is inserted into the outlet 9, the red light emitting portion 15a lights up, and when the electric device is turned on, a current flows through the cord wire 5 and an output signal is output from the rectifying circuit portion 18 to output the first semiconductor relay element. 16 is turned off to turn off the red light emitting section 15a, while the second semiconductor relay element 17 is turned on to turn on the green light emitting section 15b. Of course, the red light emitting unit 15a and the green light emitting unit 15b may be interchanged.

[Fourth Embodiment of Plug] A plug according to a fourth embodiment is a modification of the third embodiment. A semiconductor relay element 20, an LED 21, and a resistor 23 are connected in series between the plug terminals 2 and 3, and an output from the rectifier circuit 18 is supplied via a charge / discharge circuit (or a pulse generation circuit) 22 to the semiconductor relay element 20. Connected to the base. When the plug 1 is inserted into the outlet 9, the LED 21 lights up as the first state. Further, when the electric device is turned on, a pulse signal is output from the charge / discharge circuit 22, thereby turning on / off the semiconductor relay element 20 at a predetermined cycle. Accordingly, the LED 21 blinks as the second state. The blinking period may be set to a period that can be recognized by human eyes (for example, about 1 Hz). In the third and fourth embodiments, a DC power supply for control is not shown, but may be generated from a commercial power supply via a rectifier circuit, or may be provided with a battery.

[Fifth Embodiment of Plug] FIG. 5 is an external view of a plug 1 according to a fifth embodiment, and the circuit configuration is the same as that of any of the first to fourth embodiments. A display panel 24 is provided on the front surface of the LED 8, and the characters “TV” are printed on the display panel 24. Thus, it can be recognized that the television set has the plug 1 inserted into the outlet 9.

[Sixth Embodiment of Plug] FIG. 6 is an external view of a plug 1 according to a sixth embodiment, and the circuit configuration may be the same as that shown in FIG. The first display panel has the first display panel 25 and the characters "video" printed thereon, and the second display unit has the second display panel 26 and the character "do not remove" printed thereon. Thus, when the plug 1 is inserted into the outlet 9, the characters "video" can be recognized on the first display panel 25. Further, when the video switch is turned on, the character "do not disconnect" can be recognized on the second display panel 26, and it is possible to prevent the video switch from being turned off by mistake.

By providing a type display such as “TV” or “Iron” on one of the surfaces of the gabber body of the plug to determine the type of electric device to which power is supplied by the plug, You can easily recognize what plug is. The type indication can be embodied in characters, symbols, pictures and the like for healthy persons, and in braille for persons with visual impairments by embossing the braille sticker or cover surface. it can.

[First Embodiment of Plug Adapter] What has been described so far is an example in which a power supply display device having a novel function is provided in a plug. Current electrical equipment does not have the function of a new plug, but if the plug adapter described below is used, the function of the new plug can be provided. FIG. 7 is an external view of the plug adapter 30. A pair of plug terminals 31 and 32 inserted into the outlet 9, a connected terminal 33 into which the plug terminals 101 and 102 of the plug 100 of the electric device are inserted, and a first display. A section 34, a second display section 35, and a cover member 36 are provided. The circuit configuration of the plug adapter 30 shown in FIG. 2B can be employed.

[Second Embodiment of Plug Adapter] FIG. 8 shows a plug adapter according to a second embodiment. FIG. 8 (a) is a front view, FIG. 8 (b) is a rear view, and FIG. c) is a circuit diagram. Depending on the electric resistance of the electric device to which the plug adapter 30 is connected, the luminous body may not be lit on the second display unit 35. Therefore, it is preferable to provide a sensitivity adjustment knob as shown in FIG. In the circuit diagram of FIG. 8C, elements having the same functions as those in FIGS. 2 and 4 are assigned the same reference numerals and description thereof is omitted. An output terminal from the rectifier circuit 18 is input to one input terminal of the comparator 40. Between the plug terminals 2 and 3, the semiconductor relay element 41, the resistor 42 and the LED 43 are connected in series, the output terminal of the comparator 40 is connected to the base of the semiconductor relay element 41, and the ON / OFF of the semiconductor relay element 41 is controlled. Control. The resistor 44 and the variable resistor 45 are connected in series to the plus side of the built-in small battery 46, and the connection point P is connected to the other input terminal of the comparator 40. By turning the sensitivity adjustment knob 37, the value of the variable resistor 45 can be changed. Next, the operation of the circuit will be described. When the electric resistance of the electric device is large, the output voltage from the rectifying circuit 18 is small, and therefore, becomes lower than the reference voltage at the point P to be compared with the voltage, so that the semiconductor relay element 41 cannot be turned on. However, by turning the sensitivity adjustment knob 37 to lower the reference voltage, the output of the comparator 40 is inverted, whereby the semiconductor relay element 41 is turned on and the LED 43 can be turned on.

[Third Embodiment of Plug Adapter] FIG. 9 is an external view of a plug adapter 30 according to a third embodiment. The display panel 38 is provided. Examples of the display panel include a display panel having no display character indicated by 38a, a display panel printed with the letters "FAX" indicated by 38b, and a panel printed with the characters "TV" indicated by 38c. What is necessary is just to change suitably according to the kind of electric equipment connected.

[First Embodiment of Power Tap] FIG. 10 shows an example applied to a power tap 50. The power tap 50 includes a plurality of outlets 51a to 51d, a first display unit 53, a second display unit 52a to 52d of the tap 50, a code line 54, and a cover member 55. A plug 56 to be inserted into the outlet 9 is provided at the end of the cord wire 54. The first display section 53 indicates that the plug 56 of the tap 50 has been inserted into the outlet 9. The second display sections 52a to 52d respectively indicate that the plugs of the electric devices are inserted into the outlets 51a to 51d and the switches of the electric devices are turned on. FIG. 10 (b) shows a circuit configuration, which is basically the same as that shown in FIG. A resistor 57 and an LED 58 are connected in parallel between the pair of code lines 54. Each of the outlets 51a to 51d includes an induction coil 59a to 59d, resistors 60a to 60d, and LEDs 61a to 61d.

[Second Embodiment of Power Tap] FIG. 11 shows a second embodiment of the power tap 50. This embodiment is characterized by the shape of the second display portions 62a to 62d, and is formed in a frame shape so as to surround the outlets 51a to 51d.

[Embodiment of AC Adapter] FIG. 12 shows an example in which the present invention is applied to an AC adapter 64 used for a CD radio cassette player and the like. The AC adapter 64 includes a plug terminal 65, a main body 66, a code line 67, and a display unit 68 provided in the middle of the code line 67. A sticker 69 on which the number “3” is printed is attached to the main body 66. The display unit 68 is also provided with a display panel 70 on which the number “3” is printed. As the circuit configuration provided in the display section 68, those described with reference to FIGS. 2 to 4 can be applied. When the plug terminal 65 is inserted into the outlet, the illuminant lights on the display panel 68. Further, when the switch of the electric device is turned on, the display mode can be changed.

[Embodiment of Grinder] FIG. 13 shows an embodiment in which the features of the present invention are applied to a grinder 71. The grinder 71 has a device main body 72, a code line 73, a plug 74, and a display unit 75 having a display panel 76. The display unit 75 is provided at an end (root portion) of the code line 75. When the switch of the grinder 71 is turned on, a loud motor sound is heard, but an operating sound may not be heard for a person with weak hearing. This is the same when the surrounding environment is noisy. In such a case, if the display is performed on the display panel 76, the user can be surely recognized.

FIG. 14 is an embodiment in which the features of the present invention are applied to a kotatsu 77. The kotatsu 77 includes a device main body 78, a code line 79, a plug 80, a switch main body 81, a switch 82, and a display panel 83. The display panel 83 displays the message "Be careful not to unplug! Is printed, and it is possible to prevent leaving the switch 82 of the kotatsu 77 turned on and going out or going to bed.

[Seventh Embodiment of Plug] A plug according to a seventh embodiment will be described with reference to FIG. FIG. 15A is an external view, and FIG. 15B is a circuit diagram. In addition to the first display unit 10 and the second display unit 11, a third display unit 91 is provided. This indicates that the voltage has dropped. In the circuit diagram (b), the output from the rectifier circuit section 18 is connected not only to the base of the semiconductor relay element 20 but also to the input terminal of the comparator 40. The voltage of the battery 46 is divided by the resistors 88 and 89 to generate a reference voltage, which is compared with the output from the rectifier circuit unit 18 described above. The output terminal of the comparator 40 is input to the inverter and the base of a semiconductor relay element 85, and the semiconductor relay element 85 is connected in series with a resistor 86 and an LED 87. The LED 87 corresponds to the third display section 91.

When the voltage decreases, the output from the rectifier circuit 18 decreases and the output of the comparator 40 is inverted, so that the semiconductor relay element 85 is turned on and the LED 87 is turned on. This makes it possible to recognize that the voltage has dropped. It is preferable to make the emission colors of the LEDs 8, 21, and 87 different from each other so that the user can immediately know the current situation. More preferably, a circuit breaker that operates when the voltage drops is incorporated. The breaker is inserted, for example, into the line of the plug terminal 3 and cuts off the circuit when the voltage drops. If the voltage level at which the LED 87 is turned on is set higher than the voltage level at which the breaker operates, the third display unit 91 can recognize in advance that it is immediately before the breaker operates, and can use a personal computer or the like. There is no saying that data is accidentally lost. As a modified example, the number of LEDs as light emitters is reduced by using a two-color LED (similar to the plug in FIG. 3) or by controlling lighting / flashing (similar to the plug in FIG. 4). Is also good.

[Fourth Embodiment of Plug Adapter] FIG. 16 shows an appearance of a plug adapter 30 according to a fourth embodiment, which is different from the embodiment of FIG. That is. This has the same function as the third display section 91 described with reference to the plug of FIG.

[Third Embodiment of Power Tap] FIG. 17 shows a power tap 50 according to a third embodiment. The difference from the embodiment shown in FIG. 10 is that a level indicator 95 is provided. This level indicator 95 is composed of eight LEDs, and recognizes the state of power consumption. As a result, it is possible to prevent the breaker from falling and the cord wire 54 from having heat. The display such as "1200W", "600W", "300W" is printed, and the power consumption can be understood at a glance.

[Fourth Embodiment of Power Tap] FIG. 18 shows a power tap 50 according to a fourth embodiment. Similarly, a level indicator 96 is provided, and is recognized by the display of "danger" and "usable". The display panel 97 is also large, and the characters "ON" are printed on the display panel 97 itself.

[Brief description of the drawings]

FIG. 1 is an external view and a circuit diagram of a plug according to a first embodiment.

FIG. 2 is an external view and a circuit diagram of a plug according to a second embodiment.

FIG. 3 is a circuit diagram of a plug according to a third embodiment.

FIG. 4 is a circuit diagram of a plug according to a fourth embodiment.

FIG. 5 is an external view of a plug according to a fifth embodiment.

FIG. 6 is an external view of a plug according to a sixth embodiment.

FIG. 7 is an external view of a plug adapter according to the first embodiment.

FIG. 8 is an external view and a circuit diagram of a plug adapter according to a second embodiment.

FIG. 9 is an external view of a plug adapter according to a third embodiment.

FIG. 10 is an external view and a circuit diagram of a power tap according to the first embodiment.

FIG. 11 is an external view of a power strip according to a second embodiment.

FIG. 12 is an external view of an AC adapter according to the embodiment.

FIG. 13 is an external view of a grinder according to the embodiment.

FIG. 14 is an external view of a kotatsu according to the present embodiment.

FIG. 15 is an external view and a circuit diagram of a plug according to a seventh embodiment.

FIG. 16 is an external view of a plug adapter according to a fourth embodiment.

FIG. 17 is an external view of a power strip according to a third embodiment.

FIG. 18 is an external view of a power tap according to a fourth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plug 2, 3 Plug terminal 4 Cover member 5 Code wire 6 Display part 8 LED 10 First display part 11 Second display part

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[Procedure amendment]

[Submission date] April 27, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 10

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claim 18

[Correction method] Change

[Correction contents]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] Claim 21

[Correction method] Change

[Correction contents]

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] Claim 22

[Correction method] Change

[Correction contents]

Claims (25)

[Utility model registration claims] 1. A power supply display device comprising first display means for displaying a state of insertion of a plug of an electric device into an outlet. 2. The power supply display device according to claim 1, wherein said first display means is a light emitter, and said plug is inserted into said outlet to light said light emitter. 3. The power supply display device according to claim 1, further comprising a second display unit that displays a state of current supply from the plug to the electric device. 4. The first display means is a first light emitter, and the plug is inserted into the outlet so that the light emitter is turned on. 4. The second display means 4. The power supply display device according to claim 3, wherein the power supply display device is a second light emitter, and is configured to turn on the second light emitter when the electric device is energized. 5. 5. The light-emitting color of the first light-emitting body and the second light-emitting body,
5. The power supply display device according to claim 4, wherein the light emission color of the light emitting body is different. 6. The power supply display device according to claim 3, wherein the first display means and the second display means are shared by the same light emitter. 7. The illuminant is lit in a first state when the plug is inserted into the outlet, and the illuminant is lit in a second state different from the first state when the electric device is energized. The power supply display device according to claim 6, wherein: 8. When the plug is inserted into the outlet, the illuminant is lit in a first luminescent color, and when the electric device is energized, the illuminant is lit in a second luminescent color. The power supply display device according to claim 6, wherein: 9. A display panel provided on a front surface of said illuminant, and said display panel provides a display for visually specifying an electric device to be operated by inserting said plug. 3. The power supply display device according to 2. 10. The first display, comprising: a first display panel provided on a front surface of the first light emitter, and a second display panel provided on a front surface of the second light emitter. In the panel, it is possible to display a visually identifiable electric device that is operated by inserting the plug, and to cause the second display panel to perform a visual display so that removal of the plug can be prohibited. Characteristic power supply display device. 11. The power supply display device according to claim 3, further comprising voltage detection means for detecting a voltage drop, and third display means for displaying that the voltage has dropped. 12. The first display means comprises a first light emitter, the second display means comprises a second light emitter, and the third display means comprises a third light emitter. The power supply display device according to claim 11, wherein each of the light-emitting members has a different emission color. 13. The first display means and the third display means are shared by the same light emitter, and when detecting a decrease in voltage, switch the light emitter from the first lighting state. The power supply display device according to claim 11, wherein the power supply display device is switched to a second lighting state different from the first lighting state. 14. The first display means and the third display means are shared by the same light emitter, and switch the emission color of the light emitter when a voltage drop is detected. The power supply display device according to claim 11, characterized in that: 15. The power supply display device according to claim 11, further comprising a breaker that cuts off a power supply line when the voltage drops. 16. A plug comprising the power supply display device according to claim 1. Description: 17. A plug adapter comprising the power supply display device according to claim 1. Description: 18. The plug adapter according to claim 17, further comprising a sensitivity adjustment mechanism for adjusting the sensitivity for turning on the second light emitter. 19. An AC adapter provided with the power supply display device according to claim 1. Description: 20. A power tap provided with the power supply display device according to claim 1, comprising: a plug inserted into an outlet; and a plurality of outlets to which a plug of an electric device can be connected. A power tap characterized by being provided. 21. The second display means is a light emitter,
21. The power tap according to claim 20, wherein the light emitter is provided in each of the plurality of outlets. 22. The second display means is a light emitter,
21. The power tap according to claim 20, further comprising a frame-type display section surrounding the periphery of the outlet. 23. The power tap according to claim 20, further comprising a detecting unit for detecting a current or power level, and a display unit for displaying the current or power level. 24. An electric apparatus provided with the power supply display device according to claim 1, wherein a main body of the electric apparatus, a code line connecting the main body and the plug, and an intermediate part of the code line are provided. Alternatively, the electric device is provided with the first display means at an end. 25. The first display means includes a luminous body and a display panel provided on a front surface of the luminous body, and a visual display on the display panel so that the user can be careful not to forget to remove the plug. The electric device according to claim 24, wherein