JPH0946889A - Grounding confirming device for electric apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a defect in electric apparatus and ensure safety for operators, by detecting whether a grounding circuit is grounded or not in an electronic circuit in an electronic apparatus, and indicating an information signal of sound or light when the grounded state or non-grounded state is detected. SOLUTION: In an electric circuit 11, a neon lamp (detector and alarm) 3 is provided between a power terminal 10 on AC potential side and a grounding terminal 16. The neon lamp 3 is lightened when an AC power supply is put in forward connection with a voltage-side terminal of the AC power supply 7 connected to the power terminal 10 and a grounding-side terminal of the AC power supply 7 connected to the power terminal 10, and a grounding wire 15 is surely grounded. The neon lamp 3 is mounted in a place easy to see for an operator on an exterior case of an electric warm bath. When the neon lamp 3 is not lightened, the operator may check the grounding of the grounding wire 15 or the inserting direction of the plug in an outlet so as to enlighten the neon lamp 3.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to various electric and electronic devices such as a refrigerator, a washing machine, and an electric hot water bath for heating hot water in a bath, and when the devices are not grounded, the user is informed of the fact. Or to prevent the equipment from operating and to prevent accidents such as electric leakage and electric shock due to poor grounding.
Especially, it is very useful for preventing electric shock due to electric leakage in electric equipment used around water such as a bathroom or kitchen.

[0002]

2. Description of the Related Art Most electric appliances are provided with a ground. The earth is provided for the purpose of keeping the electrostatic potential of a part of an electric device equal to the potential of the earth, using the earth as a part of an electric circuit, and preventing an excessive current from entering the device.

The following are examples of grounding in various electric and electronic devices. FIG. 4 shows an example in which it is attached to the main body of the electric device A as a single electric wire, and is often used in home electric appliances such as refrigerators, washing machines, dryers, and electric hot water baths. This ground wire B is connected to this terminal if the house is equipped with a ground wire connection terminal, and if there is no ground connection terminal, it is connected to a ground rod inserted into the ground.

FIG. 5 shows an example in which a ground wire is attached to an outlet plug D of a power cord C of an electric device A, which is often used in electronic devices such as computers.
Two of the outlet plugs D are contacts E for power supply, and one is a contact F for grounding. In this case, grounding is completed simply by inserting the outlet plug D into a three-terminal outlet (outlet with ground). However, there are not many three-terminal outlets, and in general, most conventional two-terminal outlets are used. Therefore, a conversion adapter G (FIG. 6) for converting a three-terminal plug into a two-terminal plug is attached to such a device, and can be connected to an outlet through the adapter G. However, in this case, the ground wire B attached to the adapter must be separately connected to the ground connection terminal.

In the outlet E, one of the two terminals is on the ground side of 0V, and the other is + 100V to
It is the voltage side of -100V. On the other hand, the electric circuit of the electric device A and the power plug also have a ground side and a voltage side. Originally, the voltage side of the power plug is connected to the ground side of the outlet E, and the voltage of the power plug is connected to the ground side of the outlet E. It is desirable to connect the sides. Generally, even if the outlet E and the power plug are connected with the ground side and the voltage side reversed, the device A operates without any problem, but the power switch of the device A cuts only the voltage side of the electric circuit. If it is a system, outlet E
If the ground side and the voltage side are connected to each other with the ground side and the voltage side reversed, the ground side of the electric circuit will not be cut off even if the power switch is turned off, and the voltage of the outlet E is applied to the electric circuit, which may be caused by a leakage or the like. There is a risk of electric shock to the human body.

[0006]

In recent years, the number of outlet plug type electric and electronic devices equipped with a ground contact is increasing, and a household outlet is also equipped with an outlet into which the three-terminal plug can be inserted. It is becoming more and more common for equipment users to be able to automatically ground by simply connecting the power cord without worrying about grounding. However, as described above, the current situation is that the equipment cannot be grounded unless the ground wire is positively connected, and the connection of the ground wire is relatively troublesome. In many cases, there are no problems, and devices are often used without being grounded.

However, if a non-grounded device is used, there is a danger that the user may get an electric shock when a leak occurs, especially in an electric device used around water such as a bathroom or a kitchen, which is very dangerous. Further, even in electronic devices such as computers, if they are not grounded, the operation of the devices becomes unstable, which does not pose a danger to the human body but may cause a failure.

An object of the present invention is to notify the user by means as appropriate to ensure that the electric or electronic device is properly grounded, or to prevent the device from operating unless it is grounded to ensure the safety of the user or the safety of the device. An object of the present invention is to provide a grounding confirmation device for electric equipment for preventing failure.

[0009]

As shown in FIG. 1, a grounding confirmation apparatus for an electric device according to claim 1 of the present invention is arranged in an electric circuit 1 of an electric device, and a ground circuit 2 in the electric circuit 1 is grounded. The detection / notification device 3 is provided which detects the presence or absence of the signal and outputs notification information such as sound or light when a non-grounded or grounded condition is detected.

As shown in FIG. 2, the grounding confirmation apparatus for electric equipment according to claim 2 of the present invention is a detection device for detecting whether or not the grounding circuit 2 in the electric circuit 1 is grounded. A circuit 4 and an annunciator 5 that outputs announcing information such as sound and light when the detection circuit 4 detects ungrounded or grounded are provided.

As shown in FIGS. 2 and 3, the grounding confirmation apparatus for electric equipment according to claim 3 of the present invention detects the presence or absence of grounding of the grounding circuit 2 in the electric circuit 1 of the electric equipment. And a circuit breaker 6 that interrupts a part or the whole of the electric circuit 1 when the detection circuit 4 detects non-grounding.

A grounding confirmation apparatus for electric equipment according to a fourth aspect of the present invention detects the presence or absence of grounding of the earth circuit 2 in the electric circuit 1 of the electric equipment, and the power source of the electric circuit 1. By detecting whether or not the ground side and the voltage side of the plug are properly connected to the ground side and the voltage side of the AC power supply 7, whether the ground circuit 2 is ungrounded or grounded, and the connection direction of the power plug to the AC power supply 7 is determined. A detection / notification device 3 is provided which outputs notification information such as sound or light when both normal or reverse or both are detected.

A grounding confirmation apparatus for electric equipment according to a fifth aspect of the present invention detects the presence or absence of grounding of the ground circuit 2 in the electric circuit 1 of the electric equipment, and the power source of the electric circuit 1. A detection circuit 4 for detecting whether or not the ground side and the voltage side of the plug are properly connected to the ground side and the voltage side of the AC power supply 7, and the detection circuit 4 allows ungrounded or grounded ground circuit 2 to the AC power supply 7. The notification device 5 that outputs notification information such as sound or light when either or both of the connection direction of the power plug and the reverse direction is detected.

A grounding confirmation apparatus for electric equipment according to a sixth aspect of the present invention detects the presence or absence of grounding of the ground circuit 2 in the electric circuit 1 of the electric equipment, and the power source of the electric circuit 1. A detection circuit 4 for detecting whether or not the ground side and the voltage side of the plug are properly connected to the ground side and the voltage side of the AC power supply 7, and the detection circuit 4 does not ground the earth circuit 2 and the power plug to the AC power supply 7. And the reverse connection of the above, or a circuit breaker 6 for interrupting a part or the whole of the electric circuit 1 when detected.

[0015]

First Embodiment FIG. 1 is an electric circuit diagram showing a first embodiment of an earth confirmation device for electric equipment of the present invention, in which the electric equipment is an electric warm bath machine used in a bathroom. This is an example of the case. A part of the electric hot water bath is soaked in hot water in the bathtub, and there is a strong risk that a person in the bathtub may get an electric shock if a leak or the like occurs.

The electric circuit 1 of the electric hot water bath has a power supply terminal 1
The power plugs wired to 0 and 11 are connected to an AC power source (commercial power source for general household) 7 and supplied from the power source 7.
Operates at C100V. Of the power supply terminals 10 and 11, the power supply terminal 10 is a terminal that connects the voltage side of the AC power supply 7, and the power supply terminal 11 is a terminal that connects the ground side of the AC power supply 7. Between the two power supply terminals 10 and 11, a heater 12 that takes in hot water in the bathtub and heats the hot water, a motor 13 that jets the heated hot water together with air into the bathtub, and an AC 100V AC power supply 7 DC12
The power supply device 14 for converting into V is connected. In this electric circuit 1, there is an earth circuit 2 which serves as a frame earth of the electric warm bath, and the earth circuit 2 has an earth wire 15
A ground terminal 16 is provided. In this electric circuit 1, all the wirings with the earth symbol are connected to this earth circuit 2, and are actually connected to the metal frame of the electric hot water bath.

In the electric circuit 1, a neon lamp (detector / notifier) 3 is wired between a power supply terminal (terminal on the AC potential side) 10 and a ground terminal 16. In this neon lamp 3, the power supply terminal 10 is connected to the voltage side of the AC power supply 7,
In addition, the power source terminal 11 is turned on for the first time in the state where the ground side of the AC power source 7 is connected and the connection in the positive direction is made and the ground line 15 is grounded. Conversely, even if the connection of the AC power supply 7 to the power supply terminals 10 and 11 is in the opposite direction or the ground wire 15 is ungrounded, the neon lamp 3 should not light up. Has become.

The neon lamp 3 is attached to the outer case of the electric water bath at a position where it can be easily seen by the user.
When the neon lamp 3 is not turned on, the user confirms the grounding of the ground wire 15 and the direction of the plug inserted into the outlet so that the neon lamp 3 is turned on. In this way, even if the electric circuit 1 of the electric hot water bath should leak electricity, it is possible to prevent a person who is submerged in hot water from being electrocuted in the bathtub.

The heater 12 and the motor 13 operate under the control of the controller 17 in the electric circuit 1.

[0020]

[Embodiment 2] FIG. 2 is an electric circuit diagram showing a second embodiment of an earth confirmation apparatus for electric equipment of the present invention, which is an example of an electric hot water bath similar to the above embodiment. .

In this example, the electric circuit 1 is connected to the earth circuit 2
Detection to check whether (ground wire 15) is grounded and also to check whether the ground side and voltage side of the power plug of the electric circuit 1 are properly connected to the ground side and voltage side of the AC power supply 7. A circuit 4 is provided. In this detection circuit 4, a neon lamp 20 is connected between a ground terminal 16 and a power supply terminal 10. In the neon lamp 20, a ground wire 15 is grounded, and the AC power supply 7 is properly connected to the power supply terminals 10 and 11. It is designed to light only after is connected. Further, this detection circuit 4 is provided with a Cds (photoelectric element that generates electricity when receiving light) 21 adjacent to the neon lamp 20, and the output voltage from the Cds 21 is input to the comparators 26 and 27. There is. In addition, DC12V from the power supply device 14 is applied to both comparators 26 and 27.
Is also input, and both comparators 26 and 27 have Cd
The voltage from s21 and the DC 12V from the power supply device 14 are compared. In this case, when the ground wire 15 is grounded and the power plug is properly connected to the outlet, the neon lamp 20 lights and both comparators 26 and 2 are connected.
1.5V is input to 7, and one comparator 27
The ON signal is output from the alarm device (green LED) 5 is turned on, the ground terminal 16 is not grounded, and the power plug is not properly connected to the outlet, the neon lamp 20 is turned off. Both comparators 26, 2
0.5V is input to 7, which causes the other comparator 26
The ON signal is output from the device and the alarm device (red LED) 5 is turned on.

The user of the electric bath uses the red and green LEDs mentioned above.
It is possible to know whether or not the ground wire 15 of the electric device is properly grounded by turning on or off 5 and whether the power plug is correctly connected to the outlet. A combination of the neon lamp 20 and the Cds 21 is also called a neon coupler.

In the present invention, a buzzer may be attached as an alarm instead of the LED 5, and in this case, the buzzer is activated when the ground wire 15 is grounded and the power plug is not properly inserted into the outlet. To do. The LED 5 and the buzzer may be attached together.

On the voltage side circuit connecting the power supply terminal 11 of the electric circuit 1 to the heater 12 and the motor 13, a relay for opening and closing the circuit and a switch circuit 23 for switching the relay 22 to open and close the circuit. A circuit breaker 6 consisting of The switch circuit 23 is connected to the output side of the comparator 27 of the detection circuit 4, and the comparator 27 outputs an ON signal (the ground terminal 16 is grounded, and the power plug is properly connected to the outlet). (If it is present), the circuit connecting the power supply terminal 11, the heater 12 and the motor 13 is closed by the relay 22 to supply electric power to them. In parallel with this, the relay 22 is provided with an LED 24 for notifying the state of the relay 22. When the LED 24 is turned on, the circuit is connected, and when it is turned off, the circuit is cut off. Represent.

Electric circuit 1 in the first and second embodiments
The configuration of is an example, and the configuration is not limited to these.

[0026]

According to the grounding confirmation apparatus for electric equipment according to claims 1 and 2 of the present invention, when the grounding circuit is not grounded, it is reported as light or sound, and an electric shock accident due to forgetting to ground the grounding wire. Etc. can be prevented. Further, since light and sound are notified until the earth circuit is grounded, it also has the effect of prompting the user to connect the earth wire to the ground, and it is possible to prevent an accident due to a ground failure.

In the earth confirming device for electric equipment according to claim 3 of the present invention, unless the earth circuit is grounded, the electric equipment does not operate or the circuit to which a high voltage is applied is stopped, so that an accident due to a ground failure can be reliably prevented. can do.

In the earth confirmation device for electric equipment according to claims 4 and 5 of the present invention, when the earth circuit is not grounded or the power plug is not connected to the outlet in the normal direction, it is turned on. It is reported as a sound, and it is possible to prevent an electric shock accident caused by forgetting to ground the ground wire or inserting the power plug incorrectly. In addition, since light and sound are notified until the earth circuit is grounded or the plug is correctly connected, it also has the effect of prompting the user to ground the earth wire and connect the plug correctly. Can prevent accidents.

In the grounding confirmation apparatus for electric equipment according to claim 6 of the present invention, the electric equipment does not operate or a high voltage is applied unless the grounding circuit is grounded and the power plug is not properly connected to the outlet. It is possible to reliably prevent an accident such as an electric shock due to the circuit being stopped and a ground failure or a wrong plug insertion.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an example of an embodiment of a grounding confirmation apparatus for electric equipment of the present invention.

FIG. 2 is a circuit diagram showing another embodiment of the grounding confirmation apparatus for electric equipment of the present invention.

FIG. 3 is a partially enlarged view of a circuit breaker in the circuit of FIG.

FIG. 4 is a schematic diagram showing an example of a ground wire in an electric washing machine.

FIG. 5 is a schematic diagram showing an example of a ground wire in a computer.

FIG. 6 is a schematic view showing an example of an adapter for converting a grounded outlet plug into a two-terminal outlet plug.

[Explanation of symbols]

 1 Electric circuit 2 Ground circuit 3 Detection / informing device 4 Detection circuit 5 Informing device 6 Circuit breaker 7 AC power supply

Claims (6)

[Claims] 1. An electric circuit (1) of an electric device detects whether or not the earth circuit (2) in the electric circuit (1) is grounded, and when no grounding or grounding is detected, sound or light is detected. A grounding confirmation device for electric equipment, comprising a detection / notification device (3) for outputting notification information such as. 2. A detection circuit (4) for detecting whether or not the earth circuit (2) in the electric circuit (1) is grounded in the electric circuit (1) of the electric device, and the detection circuit (4) not grounding or An earth confirmation device for electric equipment, comprising: an alarm (5) that outputs alarm information such as sound and light when a grounded contact is detected. 3. A detection circuit (4) for detecting the presence / absence of grounding of the earth circuit (2) in the electric circuit (1) of the electric device and a non-grounded state by the detection circuit (4). A grounding confirmation device for electric equipment, comprising: a circuit breaker (6) for breaking a part or the whole of an electric circuit (1) when detected. 4. An electric circuit (1) of an electric device, wherein the presence or absence of grounding of the earth circuit (2) in the electric circuit (1) is detected, and the ground side and the voltage side of the power plug of the electric circuit (1) are detected. Detecting whether or not the AC power supply (7) is properly connected to the ground side and the voltage side, the ground circuit (2) is either ungrounded or grounded, and the positive direction of the connection of the power plug to the AC power supply (7) is detected. On the contrary, a grounding confirmation device for electric equipment, comprising a detection / notification device (3) for outputting notification information such as sound or light when either or both of them are detected. 5. An electric circuit (1) of an electric device is detected whether or not the earth circuit (2) in the electric circuit (1) is grounded, and the ground side and voltage side of a power plug of the electric circuit (1) are detected. A detection circuit (4) for detecting whether or not it is properly connected to the ground side and the voltage side of the AC power supply (7), and an ungrounded or grounded ground circuit (2) by the detection circuit (4), an AC power supply ( Electricity characterized by being provided with an alarm device (5) that outputs alarm information such as sound and light when both or either of the forward and reverse directions of connection of the power plug to 7) is detected. Equipment ground confirmation device. 6. An electric circuit (1) of an electric device, which detects whether or not the earth circuit (2) of the electric circuit (1) is grounded, and the ground side and voltage side of a power plug of the electric circuit (1) are detected. A detection circuit (4) for detecting whether or not the ground side and the voltage side of the AC power supply (7) are properly connected, and a grounding circuit (2) not grounded by the detection circuit (4) to the AC power supply (7). And a reverse connection of the power plug, and a circuit breaker (6) for interrupting a part or the whole of the electric circuit (1) when detected, or a grounding for electric equipment. Confirmation device.