JPH1127847A - Electrification preventive device and ozone germicidal device with electrification preventive function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely discontinue the operation of a high voltage circuit, when a grounding wire is disconnected from a connection part and other disconnection is produced. SOLUTION: If the disconnection of a grounding wire 14a or 14b, etc., is produced, a current flows between an S-phase and an R-phase through respective light-emitting diodes (27a and 27b) and (28a and 28b) of 1st and 2nd photocouplers 27 and 28 and 1st and 2nd phototransistors 27c and 28c are electrically continuous except in a range where a current flowing through the light- emitting diodes 27a, 27b, 28a and 28b is close to zero. Although an electrolytic capacitor 48 is charged while the two phototransistors 27c and 28c are not electrically continuous, the time constant of a charging circuit is so predetermined as to have the charged voltage of the electrolytic capacitor 48 lower than a voltage level by which a drive transistor 45 is turned on, until the two phototransistors 27c and 28c are turned on again. As a result, a 2nd switching contact 18 is opened, and a power supply to a high voltage power supply unit 3 is cut off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the prevention of electric shock in electronic equipment and the like, and more particularly to an electric shock prevention device and an ozone sterilizer having an electric shock prevention function in various devices having a high voltage circuit.

[0002]

2. Description of the Related Art Conventionally, a device having a high voltage circuit, for example,
In a device such as a so-called ozone sterilizer, use of a ground wire is a common sense technology from the viewpoint of preventing electric shock to a high voltage generated by a high voltage circuit. For example, FIG. 6 shows a configuration example of a conventional ozone sterilizing apparatus. Referring to FIG. 6, the use of a ground wire for preventing a high-voltage electric shock will be described. Is an ozone generator 4 for generating ozone, and a high-voltage power supply unit 3 for supplying a predetermined high voltage to the ozone generator 4.
They are roughly divided into:

The ozone generator 4 and the high-voltage power supply unit 3 are provided with ground terminals 12 and 13, respectively.
A ground line 14b is connected to the power supply plug 15 from the ground terminal 12 of the high-voltage power supply unit 3 while being connected to each other by a ground line 14b. On the other hand, 100 V commercial power supplied from the outside via the power plug 15 is usually
S phase grounded on the power supply side, and R
The R-phase and the S-phase are applied to the high-voltage power supply unit 3 via the earth leakage breaker 16, and one power line between the earth leakage breaker 16 and the high-voltage power supply unit 3 is provided. A first switching contact 17 that is opened and closed by the control circuit 19 is inserted into the (R-phase side). That is, the control circuit 19 controls the operation of the ozone sterilizer, and opens and closes the first switching contact 17 in response to pressing of an operation switch (not shown) or the like.

[0004]

However, even if an earth wire is used as described above, it is not always possible to completely prevent electric shock in every case, and depending on the situation, sufficient care must be taken when using the device. May be required. That is, in the above-described conventional configuration, if the ground wire between the power plug 15 and the ground terminals 12 and 13 is broken, the ground terminals 12 and 13 are disconnected, or the high-voltage power supply unit 3 and the inside of the ozone generator 4 are temporarily disconnected. When the ground wire is broken or when the user attaches a three-pole to two-pole conversion plug to the power plug 15, the ground wire connected to the power plug 15 becomes a commercial power source side (not shown). When it is not grounded by the
Since the housings of the high-voltage power supply unit 3 and the ozone generator 4 float from the so-called ground, there is a problem that there is a risk of electric shock.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides an electric shock prevention device capable of preventing a risk of electric shock when a ground wire is disconnected or disconnected from a connection portion of the ground wire. An object of the present invention is to provide an ozone sterilizer having an electric shock prevention function. Another object of the present invention is to ensure that the operation of the high-voltage circuit is stopped when the ground wire is disconnected or the ground wire is disconnected from the connection portion, to prevent electric shock, and to achieve a better An object of the present invention is to provide an electric shock prevention device capable of improving reliability and safety and an ozone sterilizing device having an electric shock prevention function. Another object of the present invention is to provide an electric shock prevention device capable of reliably preventing electric shock irrespective of a broken portion of a ground wire and an ozone sterilization device having an electric shock prevention function.

[0006]

According to a first aspect of the present invention, there is provided an electric shock prevention apparatus, comprising: a high voltage generating means for generating a high voltage using a single-phase commercial power supply as an input power supply; High voltage operating means that operates upon receiving the supply of, between the high voltage generating means and a power plug for inputting the single-phase commercial power and between the high voltage generating means and the high voltage operating means, An electric shock prevention device in a high-voltage use device connected by a ground wire, wherein the line voltage between one phase of the single-phase commercial power supply and the ground wire or the other phase of the single-phase commercial power supply and the ground wire A line voltage detecting means for detecting that one of the line voltages of the line voltage is equal to or less than a predetermined value, and a line voltage detecting means for detecting that one of the line voltages is equal to or less than a predetermined value. Only if it is detected And power supply control means allowing the single-phase commercial power supply to the serial high-voltage generating means is made comprises a.

In the electric shock prevention device having such a configuration, in the case of a single-phase commercial power supply, one of the phases is grounded on the supply side of the commercial power supply, and the ground-side phase is connected to a ground wire provided in the high-voltage use device. In between, if the ground is perfect, no potential is originally generated, the ground wire is, for example,
In the case of disconnection, attention is paid to the floating of the ground line. That is, when the ground wire is properly connected, no potential is generated between the ground-side phase of the single-phase commercial power supply and the ground wire. In this case, only in this case, it is possible to supply power to the high voltage generating means by the power supply means, and to minimize the danger of high voltage electric shock due to disconnection or disconnection from the connection part of the ground wire. It was done.

According to a third aspect of the present invention, there is provided an electric shock prevention apparatus, comprising: a high voltage generating means for generating a high voltage using a single-phase commercial power supply as an input power supply; High-voltage operating means, and the high-voltage generating means and the power plug for inputting the single-phase commercial power, and the high-voltage generating means and the high-voltage operating means are connected by a ground wire, An electric shock prevention device in a high-voltage use device, comprising: a line voltage between one phase of the single-phase commercial power supply and the ground wire or a line voltage between the other phase of the single-phase commercial power supply and the ground wire. Line voltage detecting means for detecting that one of the line voltages is equal to or higher than a predetermined value, and that the line voltage detecting means detects that one of the line voltages is equal to or higher than a predetermined value. Only if the high voltage generating means , And a power supply control means for enabling supply of said single-phase commercial power source to be made comprises a.

In the electric shock prevention device having such a configuration, in the case of a single-phase commercial power supply, one of the phases is grounded on the supply side of the commercial power supply, and the ground-side phase is connected to a ground wire provided in the high-voltage use device. In the meantime, if the ground is perfect, no potential is originally generated, but if the ground wire is broken, for example, the potential of the ground wire is floated, . That is, when the ground wire is properly connected, a potential corresponding to the commercial power supply voltage is generated between the ungrounded phase of the single-phase commercial power supply and the ground wire. In such a case, such a potential is not generated. In the above configuration, this is detected by the line voltage detecting means, and only in that case, power can be supplied to the high voltage generating means by the power supply means. The risk of high-voltage electric shock due to disconnection or disconnection of the ground wire from the connection portion can be avoided as much as possible.

According to a fifth aspect of the present invention, there is provided an electric shock prevention device, wherein an earth leakage breaker is provided between the high voltage generating means and the power plug, and a detection point of the potential by the line voltage detection means is the earth leakage breaker. Is the upstream side of.

[0011] Such a configuration takes into account the malfunction of the earth leakage breaker. That is, if the detection point of the potential by the line voltage detecting means is on the downstream side of the earth leakage breaker, there is a risk that the earth leakage breaker malfunctions due to the current flowing into the photocoupler constituting the line voltage detecting means.
By setting the upstream side as in the above-described configuration, such a risk can be avoided, and more reliable prevention of electric shock can be achieved.

In the electric shock prevention device according to the present invention, the connection point of the line voltage detecting means to the ground wire is a ground terminal provided in the high voltage generating means or the high voltage operating means. With such a configuration, for example, when the connection point to the ground wire is located between the power plug and the ground terminal of the high-voltage generating means, the disconnection of the ground wire causes the connection point to be connected to the ground terminal of the high-voltage generating means. In such a case, consider that the connection point to the ground wire from the line voltage detection means may still be grounded via the ground wire remaining on the power plug side. With such a configuration, power supply to the high-voltage generating means can be reliably shut off regardless of the broken position of the ground wire, and the reliability can be further improved. It is what becomes.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS. The electric shock prevention device according to the embodiment of the present invention is an example applied to an ozone sterilization device. First, the configuration and operation of the ozone sterilization device will be schematically described with reference to FIG.
Note that the same reference numerals are given to the same components of the conventional device described above with reference to FIG. The configuration itself of the ozone sterilizer S1 as the high-pressure use device shown in FIG.
They are well-known and well-known, and do not need to have a special configuration in applying the present invention. The ozone sterilizer S1 is connected to the sterilization booth 1 via the flexible duct 2, and the ozone generated by the ozone generator 4 flows into the sterilization booth 1, thereby enabling ozone sterilization in the sterilization booth 1. It is configured to be as follows.

That is, the ozone sterilizer S1 has a predetermined repetition cycle (for example, 6 to 7) as a main component.
KHz) of a predetermined high voltage (for example, 5 to 6K).
v), an ozone generator 4 for generating ozone using a high voltage generated by the high-voltage power supply 3 as a power supply for discharge, an ozone decomposition catalyst 5, and a blower for blowing air to the sterilization booth 1. Blower fan 6, this ozone sterilizer S
1 is provided with a control device 7 for controlling the operation of the whole.

When ozone is generated and sterilized by the ozone sterilizer S1 having such a configuration, first, ozone is sterilized.
The air in the sterilization booth 1 is sucked into the chamber 8 through the flexible duct 2 on the suction side, and is being blown to the flexible duct 2 on the blowing side by the blower fan 6 through the first damper 9 for generating ozone. Thus, the mixture is mixed with the ozone generated by the ozone generator 4 and discharged to the sterilization booth 1. This behavior is
The process is repeated until the ozone concentration in the sterilization booth 1 reaches a predetermined value.

When the sterilization at the predetermined ozone concentration is completed, the air containing ozone in the sterilization booth 1 is sucked into the chamber 8 again. Is passed through the ozone decomposition catalyst 5 via the second damper 10 for decomposition,
After the ozone is decomposed, the air is blown into the sterilization booth 1 by the blower fan 6. By repeating such an operation, the ozone concentration in the sterilization booth 1 does not affect the human body. Can be lowered.

Next, a first example of an electric shock prevention device for preventing an electric shock accident due to a failure of the high-voltage power supply unit 3 in the ozone sterilizer S1 as described above will be described with reference to FIG. First, the high-voltage power supply unit 3 as the high-voltage generating means and the ozone generator 4 as the high-voltage operating means are connected to each other by a high-voltage cable 11, and the high voltage generated by the high-voltage power supply unit 3 is applied to the ozone generator. 4. The high-voltage power supply unit 3 and the ozone generator 4 are provided with ground terminals 12 and 13, respectively, which are connected to each other via a ground wire 14a, and that the ground terminal 12 and the power plug 15 are also grounded. They are connected by a line 14b. The power plug 15 has a so-called three-pole plug configuration having two poles for AC power supply and one pole for ground wire connection.

The high-voltage power supply unit 3 operates using AC100v, which is a so-called commercial power supply, as a power supply voltage.
00v is applied via the earth leakage breaker 16. Between the earth leakage breaker 16 and the power input terminals 3a and 3b of the high-voltage power supply 3,
Out of two phases, namely, an S phase connected to the ground on the supply side of a commercial power supply (not shown) and an R phase which is a non-grounded phase. 17,
18 are connected in series.

The first switching contact 17 is adapted to be opened and closed by a control circuit 19.
Numeral 9 controls the operation of the ozone sterilizer S1, and opens and closes the first switching contact 17 in response to pressing of an operation switch (not shown) or the like. On the other hand, during normal operation, that is, as described later, the second switching contact 18 is connected to the ground wire 14a by the electric shock prevention device S2.
In a state where disconnection or the like of 14b is not detected, the closed state is established and the ground wires 14a, 1 by the electric shock prevention device S2 are closed.
When the relay (shown as “Ry” in FIG. 1) 46 is operated by detecting the disconnection or the like of 4 b, the relay 46 is set to the open state. The supply of AC100v is cut off.

The electric shock prevention device S2 is roughly divided into a detection unit 25 as a line voltage detection unit and an operation control unit 26 as a power supply control unit.
It is configured with two photocouplers 27 and 28 at the center. First and second photocouplers 27, 28
Have the same configuration. In the following description of the configuration, the reference numerals of the components of the first photocoupler 27 are followed by the corresponding components of the second photocoupler 28 in parentheses. The description of the configuration of the second photocoupler 28 will be replaced with the reference numeral.

The first photocoupler 27 has two light-emitting diodes 27a and 27b (28a and 28b) provided on the light-emitting side in a so-called reverse connection state, and one of the connection ends is connected to the fourth side. (In FIG. 1, "R
4) is connected to the S phase between the earth leakage breaker 16 and the power plug 15, while the other connection end of the light emitting diodes 27 a and 27 b is connected to the second photocoupler 28. Light emitting diodes 28a, 28 constituting
b is connected to the ground line 14a together with the other mutual connection end. The mutual connection end of one of the two diodes 28a and 28b constituting the second photocoupler 28 is connected to the fifth
(Referred to as “R5” in FIG. 1) 35 is connected to the R phase between the earth leakage breaker 16 and the power plug 15.

On the other hand, the operation control unit 26 includes the first and second phototransistors 27c and 28c on the light receiving side of the first and second photocouplers 27 and 28, the driving transistor 45, and the relay 46. Is a main component, and a circuit for driving the relay 46 is configured as described later. That is, the emitter of the first phototransistor 27c is connected to the collector of the second phototransistor 28c, and the collector of the first phototransistor 27c is a first resistor (denoted as "R1" in FIG. 1). A predetermined circuit power supply voltage (for example, 12 V) is applied via the switch 31. The emitter of the second phototransistor 28c is connected to a so-called circuit ground.

Further, the first phototransistor 27c
, And an emitter of the second phototransistor 28c, a diode 47 and an electrolytic capacitor 48 are connected in series such that the cathode side of the diode 47 is the collector side of the first phototransistor 27c. Further, between the collector of the first phototransistor 27c and the emitter of the second phototransistor 28c, a second resistor (denoted as "R2" in FIG. 1) 32 and a constant voltage diode (FIG. In "Z
D) 49 and a third resistor (denoted as “R3” in FIG. 1) 33, and the cathode of the constant voltage diode 49 is connected to the collector of the first phototransistor 27 c via the second resistor 32. Are connected in series such that they are connected to

The connection point between the second resistor 32 and the cathode of the constant voltage diode 49 is connected to the anode of the diode 47, while the connection point between the anode of the constant voltage diode 49 and the third resistor 33 is provided. The point is connected to the base of an npn-type drive transistor 45. One end of a relay 46 is connected to the collector of the driving transistor 45, and a predetermined circuit power supply voltage is applied to the other end of the relay 46. Note that the emitter of the driving transistor 45 is connected to the circuit ground.

Next, the operation in this configuration will be described. First, it is assumed that the S phase is on the ground potential side. First, an operation in a state where the ground wires 14a and 14b are normally connected will be described. In this case, since no voltage is generated between the S phase and the ground wires 14a and 14b, the first photo None of the light emitting diodes 27a and 27b of the coupler 27 is in a light emitting state, so that the first phototransistor 27c is always in a non-conductive state. Therefore, the second phototransistor 2
Since 8c is equivalent to being insulated on the collector side, the second phototransistor 28c is in a non-operating state regardless of the operating state of the light emitting diodes 28a and 28b. As a result, with respect to the operation of the driving transistor 45, the first and second phototransistors 27c and 28c
Has no effect.

It should be noted that AC100 is provided between the R phase and the S phase.
Since v appears, the light emitting diodes 28a and 28b of the second photocoupler 28 alternately emit light. However, in the vicinity where the distance between the R and S phases becomes zero v, both light emitting states do not emit light.

On the other hand, the constant voltage diode 49 has first,
When a current determined by the second and third resistors 31 to 33 is supplied, a predetermined voltage is generated and applied to the base of the driving transistor 45. Therefore, the driving transistor 45 is always in a conductive state, and 46 is also always energized. Therefore, when the ground wires 14a and 14b are normally connected, the second switching contact 18 is closed, and the earth leakage breaker 16 operates or the first switching contact 17 is opened. Unless this is the case, AC 100v can be supplied to the high voltage power supply unit 3.

Next, for some reason, the ground wire 14
The operation when a and 14b are disconnected from ground terminals 12 and 13 or are disconnected will be described. In this case,
Since the potentials of the ground wires 14a and 14b are in a floating state,
A current flows through the light emitting diodes 27a, 27b, 28a, 28b through the following route. That is, with a change in the polarity of the AC power supply, the S phase → the fourth
Resistor 34 → light emitting diode 27a → earth wire 14b
→ Light emitting diode 28b → Fifth resistor 35 → R phase, and in the next half cycle, conversely, R phase → Fifth resistor 35 →
A current flows through the light emitting diode 28a → the ground wire 14b → the light emitting diode 27b → the fourth resistor 34 → the S phase. At this time, when the AC power supply is near zero v, any of the light emitting diodes 27a, 27b, 28a, 28b
Also emits no light, but otherwise, the light emitting diode 2
7a or 27ab and the light emitting diode 28
a or 28b is in a light emitting state.

Therefore, the first and second phototransistors 27c and 28c are in a conductive state when the AC power supply is not near zero v, and are non-conductive for a very short time only near zero v of the AC power supply. Becomes When the first and second phototransistors 27c and 28c are in a conductive state, the connection point between one end of the second resistor 32 and the cathode of the diode 47 is connected to the circuit ground. Is also substantially zero potential, and the drive transistor 45 is turned off. In this case, the electrolytic capacitor 48 is a diode 47
To be in a discharge state.

In a section where the first and second phototransistors 27c and 28c are in a non-conductive state,
First, a current flows through the first and second resistors 31 and 32 into the electrolytic capacitor 48 in which the electric charge is zero. As the current flows into the electrolytic capacitor 48, the potential at the cathode of the constant voltage diode 49 also gradually increases from zero v. The size of the electrolytic capacitor 48 and the sizes of the first and second resistors 31 and 32 are set such that the first and second phototransistors 27c and 28c are turned on as the AC power supply rises from near zero v. Is set in advance, so that the constant voltage diode 4
9 does not generate a constant voltage, and the drive transistor 45 does not become conductive.

Therefore, since the relay 46 is not energized, the second switching contact 18 is opened when the ground wires 14a and 14b are disconnected, and the supply of AC 100v to the high voltage power supply unit 3 is forced. Will be cut off.
Therefore, the high-voltage power supply unit 3 does not operate, and the ground wires 14a,
The risk of electric shock when the wire 14b is disconnected or the like is reliably avoided.

Next, a second circuit configuration example will be described with reference to FIGS. This second circuit configuration example is an example in which an electric shock prevention device S2 is provided in the control circuit 19 in the first circuit configuration example shown in FIG. Note that the same components as those in the first example shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

First, the connection of the ground wires 14a and 14b to the high-voltage power supply unit 3 and the ozone generator 4, and the connection between the earth leakage breaker 16 and the power plug 15 are described in the first example shown in FIG. Therefore, detailed description is omitted here. In addition, the earth leakage breaker 16 and the high voltage power supply unit 3
A common switching contact 42, which is opened and closed by the control by the electric shock prevention device S2 or by the original control of the control circuit 19, is connected in series to the R phase.

The control circuit 19 is for controlling the operation of the ozone sterilizer S1 based on the depression of an operation switch (not shown) or the like, and is constituted mainly by a microcomputer 50 represented by a so-called CPU. The microcomputer 50 is configured to be shared with the electric shock prevention device S2. In the control circuit 19, the input stage of the drive circuit 51 is connected to the third output port (denoted by "Po3" in FIG. 2) of the microcomputer 50. Under the conditions, earth leakage breaker 1
The common switching contact 42 inserted in series in one phase between the high voltage power supply unit 6 and the high voltage power supply unit 3 is opened via the drive circuit 51 to shut off power to the high voltage unit 3.
The drive circuit 51 and the common switching contact 42 are also configured to be shared with the electric shock prevention device S2 as described later.

The electric shock prevention device S2 is roughly divided into a detection unit 25A as a line voltage detection unit and an operation control unit 26A as a power supply control unit. The first example is similar to the first example, but the specific configuration is different from the first example as described below. That is, the detection unit 25A is configured with the first to fourth photocouplers 27 to 30 as main components. The first and second photocouplers 27,
Reference numeral 28 is basically the same as that used in the first example. Third and fourth photocouplers 29, 30
Are different from the first and second photocouplers 27 and 28 in that both light receiving sides are configured using phototriacs 29b and 30b.

One of the two light emitting diodes 27a and 27b of the first photocoupler 27 is connected to one end of a phototriac 29b constituting a third photocoupler 29 via a first resistor 31. The other end of the phototriac 29b is connected to the power plug 15
And the earth leakage breaker 16 are connected to the S phase.
The light emitting diode 27 of the first photocoupler 27
The other mutual connection point of a and 27b is connected to the ground line 14b together with the other mutual connection point of the two light emitting diodes 28a and 28b of the second photocoupler 28. On the other hand, the light emitting diode 2 of the second photocoupler 28
8a, 28b is connected to the second resistor 3
2 is connected to one end of a phototriac 30b of the fourth photocoupler 30. The other end of the phototriac 30b is connected to the power plug 15 and the earth leakage breaker 1b.
6 is connected to the R phase.

The operation control section 26A includes a light-emitting side of the first and second phototransistors 27c and 28c on the light receiving side of the first and second photocouplers 27 and 28, and a light-emitting side of the third and fourth photocouplers 29 and 30. Light emitting diodes 29a, 30
a, the microcomputer 50 and the drive circuit 51 described above are configured as main components. First phototransistor 27 forming first photocoupler 27
c has a collector connected to the third resistor 34 through the fourth resistor 34.
Is connected to a predetermined power supply (for example, 5 V) together with the anode of the light emitting diode 29a constituting the photocoupler 29.

The collector of the first phototransistor 27c constituting the first photocoupler 27 is connected to a fifth resistor 35 and a ninth resistor ("R9" in FIG. 2).
(Noted as "Pi1" in FIG. 2).
Further, the emitter of the first phototransistor 27c is connected to the connection point of the fifth and ninth resistors 35 and 39 via the first capacitor 52, and to the so-called circuit ground. ing. On the other hand, the collector of the second phototransistor 28c constituting the second photocoupler 28 is connected to the fourth photocoupler 30 via a seventh resistor (indicated as “R7” in FIG. 2) 37.
Is connected to a predetermined power supply (for example, 5 V) together with the anode of the light emitting diode 30a. The collector of the second phototransistor 28c is an eighth resistor 38 and a tenth resistor (denoted as "R10" in FIG. 2).
A second input port (denoted by "Pi2" in FIG. 2) of the microcomputer 50 is connected to the second input port of the microcomputer 50 via a second capacitor 53. Is connected to the circuit ground together with the emitter of the second phototransistor 28c.

The cathode of the light emitting diode 29a constituting the third photocoupler 29 is connected to the first output port of the microcomputer 50 via the third resistor 33 ("P" in FIG. 2).
o1 ”) and the fourth photocoupler 3
0 of the light emitting diode 30a,
A second output port (in FIG. 2, “P6”) of the microcomputer 50 is connected via a resistor 36 (indicated as “R6” in FIG. 2) 36.
o2 "). The microcomputer 50 has a well-known and well-known configuration including a ROM, a RAM, and the like (not shown). As described later, the microcomputer 50 outputs signals detected through the first and second input ports Pi1 and Pi2. On the basis of this, the opening and closing of the common opening / closing contact 42 is performed via the drive circuit 51. The input stage of the drive circuit 51 is connected to the third output port Po3 of the microcomputer 50. The drive circuit 51 opens and closes the common switching contact 42 according to a control signal input from the microcomputer 50. Has become.

Next, the operation in such a configuration will be described.
This will be described with reference to FIG. When the control operation by the microcomputer 50 is started, first, the S phase and the ground wires 14a, 1
In order to detect the potential between the first output port Po1 and the first output port Po1
, A signal of a predetermined level corresponding to the logical value Low is output, and the third photocoupler 29 is activated (see step 100 in FIG. 3). That is, the third
Light emitting diode 29a constituting the photocoupler 29 of FIG.
Is turned on when the cathode side is at the low level, and the phototriac 29b on the light receiving side is turned on.

Next, the logical value H is output from the second output port Po2.
A signal of a predetermined level corresponding to the signal “i.
Of the photocoupler 30 is brought into a non-operating state (see step 102 in FIG. 3). That is, the light emitting diode 30a included in the fourth photocoupler 30 is turned off when the cathode side is set to the high level, and the phototriac 30b on the light receiving side is turned off. Then, in this state, the signal at the first input port Pi1 is input (see step 104 in FIG. 3).

Next, in order to detect the potential between the R phase and the ground lines 14a and 14b, first, a signal of a predetermined level corresponding to the logical value High is output from the first output port Po1.
The third photocoupler 29 is brought into a non-operating state (see step 106 in FIG. 3). That is, the light emitting diode 29a constituting the third photocoupler 29 is in a non-light emitting state when the cathode side is set to the high level, and the photo triac 29b on the light receiving side is in a non-conductive state.

Next, the logical value L is output from the second output port Po2.
A signal of a predetermined level corresponding to ow is output, and the fourth photocoupler 30 is brought into an operating state (FIG. 3).
Step 108). That is, the light emitting diode 30a constituting the fourth photocoupler 30 is in a light emitting state when the cathode side is at the low level, and the light triac 30b on the light receiving side is in a conductive state. Subsequently, in this state, the signal level at the second input port Pi2 is input (step 1 in FIG. 3).
10).

Then, the ground lines 14a and 14b are disconnected and detached from the mounting portion due to the signal level input from the second input port Pi2 and the signal level input from the first input port Pi1. A determination is made as to whether or not there is (step 112 in FIG. 3).

Here, this determination will be specifically described. First, the signal level input to the first input port Pi1 will be described together with the circuit operation. In a state where the previous steps 100 and 102 have been executed,
Assuming that the ground lines 14a and 14b are normal, the phototriac 29b constituting the third photocoupler 29
Are in the conductive state, the light emitting diodes 27a and 27b forming the first photocoupler 27 are connected to the first resistor 3
Although the state is established between the S phase and the ground wires 14a and 14b via the first and third photocouplers 29, a voltage is generated between the S phase and the ground wires 14a and 14b. Therefore, the light emitting diodes 27a and 27b do not emit light, and the first phototransistor 27c is turned off. For this reason, the first capacitor 52 is connected to the substantially predetermined power supply voltage (for example, 5
v), the read value of the signal from the first input port Pi1 in step 104 is
It always has the logical value High.

On the other hand, if the ground wires 14a and 14b are disconnected or broken while the previous steps 100 and 102 are executed, the ground wires 14a and 1
4b floats, but the third photocoupler 2
9 is in the non-operation state, that is, the photo triac 29b
Is in a non-conducting state, so that unlike the case of the first example shown in FIG.
The current does not flow into the phase, and in this case, no current flows through the light emitting diodes 27a and 27b of the first photocoupler 27. Therefore, also in this case, since the first capacitor 52 is charged as described above, the read value of the signal from the first input port Pi1 in step 104 always becomes the logical value High.

Next, the signal level input to the second input port Pi2 will be described with respect to the circuit operation and the case where the ground lines 14a and 14b are normal and the case where the ground lines 14a and 14b are disconnected. I will decide. Assuming that the ground lines 14a and 14b are normal in the state where the previous steps 106 and 108 are executed, since the phototriac 30b constituting the fourth photocoupler 30 is conductive, the R phase and the ground line 14a , 14b flows into the light emitting diodes 28a, 28b constituting the second photocoupler 28,
The light emitting diodes 28a and 28b enter a light emitting state. Therefore, the second phototransistor 28c on the light receiving side is
Except for a section where the voltage between the R phase and the ground wires 14a and 14b is near zero v, the state is conductive, and near zero v, the state is nonconductive.

On the other hand, while the second phototransistor 28c is in the conductive state, the second capacitor 53 is short-circuited via the eighth resistor (indicated as "R8" in FIG. 2) 38. However, when the second phototransistor 28c is turned off, the seventh and eighth resistors 37, 38
Through the battery. However, the second capacitor 5c between the time when the second phototransistor 28c is turned off and the time when it is turned on again
In the charging speed of No. 3, while the second phototransistor 28c is in the non-conducting state, the charging voltage of the second capacitor 53 does not reach the level that is set to the logical value High at the second input port Pi2 of the microcomputer 50. Thus, the so-called time constant determined by the seventh and eighth resistors 37 and 38 and the second capacitor 53 is set in advance by selecting an appropriate value. Therefore, step 110
, The read value of the signal from the second input port Pi2 always has the logical value Low irrespective of the operation state of the second phototransistor 28c.

Next, if the ground wires 14a, 14b are disconnected or broken while the previous steps 106, 108 are executed, the ground wires 14a, 1
4b floats, but the third photocoupler 2
9, the first photocoupler 27 is connected to the ground wires 14a, 14b.
As in the case where b is normal, it becomes inactive. Therefore, no current flows from the S phase to the R phase, and the second photocoupler 28
Since no current flows into a and 28b, no light is emitted.

Therefore, the second phototransistor 28
c is different from the case where the ground wires 14a and 14b are normal,
It is always in a non-operation state, and the second capacitor 53
Then, the battery is charged via the eighth resistors 37 and 38, and the charged voltage reaches a substantially predetermined power supply voltage (for example, 5 V). After all, the read value of the signal from the second input port Pi2 in step 110 is the value read from the ground line 14a,
14b is disconnected or disconnected, the logical value H
It becomes igh.

Therefore, in step 112,
Of the two input signals of the first and second input ports Pi1 and Pi2, the input signal from the second input port Pi2 has a logical value Hi.
Only when the value becomes gh, it is determined that the ground wires 14a and 14b are disconnected or disconnected. If it is determined that the ground wires 14a and 14b are disconnected, a predetermined signal is output from the third output port Po3 to the drive circuit 51, and the drive circuit 51 immediately opens the common open / close contact 42. (Step 11 in FIG. 3)
4), the supply of AC 100v to the high voltage power supply unit 3 is forcibly cut off. Therefore, the high-voltage power supply unit 3 does not operate, and the danger of electric shock when the ground wires 14a and 14b are disconnected is reliably avoided.

On the other hand, in step 112, if the input signal from the first input port Pi1 is a logical value High, the input signal from the second input port Pi2 is a logical value Low, and the ground lines 14a and 14b are normal. If it is determined, the process returns to the previous step 100, and a series of processes is repeated again.

Next, a third circuit configuration example will be described with reference to FIG. This third circuit configuration example has the same configuration as that of the first circuit configuration example shown in FIG. 1 except for a part, and in the following description, the same components will be described. Are denoted by the same reference numerals, detailed description thereof will be omitted, and different points will be mainly described below.
The third circuit configuration example is different from the first circuit configuration example in that the potential detection points of the ground lines 14a and 14b, that is, the other ends of the light emitting diodes 27a and 27b forming the first photocoupler 27 are different. The other ends of the light emitting diodes 28a and 28b constituting the second photocoupler 28 are connected to the ground wire 14b between the power plug 15 and the ground terminal 12 in the first circuit configuration example. On the other hand, the high voltage power supply unit 3 is directly connected to the ground terminal 12.

With such wiring, even if the ground wire 14b is broken between the ground terminal 12 of the high-voltage power supply unit 3 and the power plug 15, the first example of the first circuit configuration will be described. As described above, the second switching contact 18 is opened, the power supply to the high-voltage power supply unit 3 is forcibly cut off,
Electric shock prevention can be more reliably achieved. That is, in the case of the first circuit configuration example shown in FIG. 1, the other ends of the light emitting diodes 27 a and 27 b forming the first photocoupler 27 and the light emitting diodes 28 a and 28 b forming the second photocoupler 28 are formed. When the ground wire 14b is disconnected between the ground terminal 14 and the connection point to the ground wire 14b to which the other end is connected, the first and second photocouplers 2
Light-emitting diodes 27a, 27b, 2 constituting the light-emitting diodes 7, 28
The other end of each of the power supply plugs 8a and 28b is still grounded via the ground wire 14b and the power supply plug 15 to the power supply plug 15, so that the second switching contact 18 does not open and close, thereby preventing electric shock. The disadvantage of not being sufficient arises.

However, by using the wiring as in the third circuit configuration example described above, the disconnection is detected without fail irrespective of the disconnection point of the ground wire 14b, and the power supply to the high-voltage power supply unit 3 is performed. It will be cut off. FIG.
In the circuit configuration example shown in FIG. 7, the other mutual connection point of the light emitting diodes 27a and 27b of the first photocoupler 27 and the light emitting diode 28 of the second photocoupler 28
Although the other mutual connection point of a and 28b is directly connected to the ground terminal 12, it may be connected to the ground terminal 13 instead of the ground terminal 12.

In the second circuit configuration example shown in FIG. 2, it is needless to say that wiring may be performed in the same manner as in the circuit configuration example shown in FIG. That is, also in FIG. 2, the light emitting diodes 27a,
27b and the other photocoupler 2
The other mutual connection point of the eight light emitting diodes 28a and 28b may be directly connected to the ground terminal 12 or the ground terminal 13.

In any of the above-described embodiments of the present invention, the ground phase and the non-ground phase are described as being clear for the sake of explanation of the operation. However, in the actual operation, the power is supplied from the power plug 15. Which phase of the commercial power supply is the ground phase,
It is not necessary to be clear whether the phase is the non-grounded phase. In actual operation, even if the phases are the reverse of the R phase and S phase shown in FIGS. 1, 2 and 3, respectively, they operate without any trouble. It is. In this case, the operations of the first and second photocouplers 27 and 28 are reversed from the above description, and the operations of the third and fourth photocouplers 28 and 30 are also different from the above description. The opposite is true.

In each of the embodiments of the present invention described above, an electric shock prevention device for preventing electric shock due to disconnection of the ground wires 14a and 14b in the high voltage power supply unit 3 used in the ozone sterilization device has been described. Needless to say, it is not necessary to limit to electric shock prevention by the high voltage power supply in the sterilization apparatus. That is, for example, in FIGS. 1, 2, and 4, the object to which the high-voltage power generated by the high-voltage power supply unit 3 is supplied does not necessarily need to be the ozone generator 4. Also, various devices that require a high voltage, such as a microwave generator used for a wireless transmitter, etc., may be used.

[0059]

As described above, according to the present invention,
In a device that uses a high voltage and uses a ground wire, a commercial power supply to the high voltage generation portion is generated based on the so-called floating of the ground potential that occurs when a disconnection or the like occurs from the connection portion of the ground wire. The power supply to the high voltage generator is cut off when the ground wire breaks, etc. Is reliably avoided, and reliability and safety can be improved more than before.

When a so-called photocoupler is used as a component of the line voltage detecting means as in the second or fourth aspect of the present invention, in addition to the above-described effects, the power supply by the photocoupler, especially Since the control means is insulated from the commercial power supply, it is possible to configure the power supply control means only with a circuit that handles a lower voltage, and it is possible to increase the safety of the circuit.

In addition, in the case of the configuration according to the fifth aspect of the present invention, in addition to the above-described effects, it is possible to prevent malfunction of the earth leakage breaker due to current consumption of the electronic components constituting the line voltage detecting means. It is possible to further improve the reliability of the device. Further, in the case of the configuration according to the sixth aspect of the present invention, in addition to the above-described effects, the supply of the commercial power can be reliably performed even if the ground wire is disconnected regardless of the location of the ground wire. The reliability and safety can be further improved.

[Brief description of the drawings]

FIG. 1 is a circuit diagram illustrating a first circuit configuration example of an electric shock prevention device according to an embodiment of the present invention.

FIG. 2 is a circuit diagram illustrating a second circuit configuration example of the electric shock prevention device according to the embodiment of the present invention.

FIG. 3 is a flowchart showing a control procedure for preventing electric shock executed by a microcomputer in the second circuit configuration example shown in FIG. 2;

FIG. 4 is a circuit diagram illustrating a third circuit configuration example of the electric shock prevention device according to the embodiment of the present invention.

FIG. 5 is a configuration diagram showing a schematic configuration of an ozone sterilization apparatus that constitutes the electric shock prevention device according to the embodiment of the present invention.

FIG. 6 is a schematic circuit diagram showing an example of wiring for preventing electric shock in a conventional ozone sterilizer for explaining an example of a conventional electric shock prevention technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 3 ... High voltage power supply part 3a, 3b ... Power input terminal 12, 13 ... Earth terminal 14a, 14b ... Earth wire 15 ... Power plug 16 ... Earth leakage breaker 17 ... First switching contact 18 ... Second switching contact 27 ... First Photocoupler 27a Light emitting diode 27b Light emitting diode 27c First phototransistor 28 Second photocoupler 28a Light emitting diode 28b Light emitting diode 28c Second phototransistor 29 Third photocoupler 29a Light emission Diode 29a Phototriac 30 Third photocoupler 30a Light emitting diode 30a Phototriac 42 Common open / close contact 45 Drive transistor 46 Relay 50 Microcomputer

Claims (7)

[Claims] A high-voltage generating means for generating a high voltage by using a single-phase commercial power supply as an input power supply; and a high-voltage operating means for operating by receiving a high voltage from the high-voltage generating means. An electric shock prevention device in a high voltage use device, wherein a voltage line is connected between a voltage generating unit and a power plug for inputting the single-phase commercial power and a line between the high voltage generating unit and the high voltage operating unit. A line voltage between one of the single-phase commercial power supply and the ground wire or a line voltage between the other phase of the single-phase commercial power supply and the ground wire is a predetermined value or less. The line voltage detecting means for detecting that the line voltage detecting means detects that one of the line voltages is equal to or less than a predetermined value. Enables supply of single-phase commercial power Electric shock prevention device comprising a power supply control means, to become comprises a. 2. The line voltage detecting means includes: a first photocoupler connected between one phase of a single-phase commercial power supply and a ground line; and a first photocoupler connected between the other phase of the single-phase commercial power supply and a ground line. A second photocoupler connected between the first and second photocouplers, the light receiving side elements of the first and second photocouplers are connected in series, and one of a single-phase commercial power supply and the ground line is connected to the other. Only when one of the line voltage or the line voltage between the other phase of the single-phase commercial power supply and the ground line is equal to or less than a predetermined value, the first line connected between the corresponding lines. 2. The electric shock prevention device according to claim 1, wherein the light receiving side element of the second photocoupler is configured to be in a non-conductive state. 3. A high-voltage generating means for generating a high voltage by using a single-phase commercial power supply as an input power supply; and a high-voltage operating means operating by receiving a high voltage supplied from the high-voltage generating means. An electric shock prevention device in a high voltage use device, wherein a voltage line is connected between a voltage generating unit and a power plug for inputting the single-phase commercial power and a line between the high voltage generating unit and the high voltage operating unit. The line voltage between one of the single-phase commercial power supply and the ground wire or the line voltage between the other phase of the single-phase commercial power supply and the ground wire is equal to or greater than a predetermined value. The line voltage detecting means for detecting that the line voltage is higher than a predetermined value is detected by the line voltage detecting means. Enables supply of single-phase commercial power Electric shock prevention device comprising a power supply control means, to become comprises a. 4. The line voltage detecting means includes: a first photocoupler having a light-emitting side connected between one phase of a single-phase commercial power supply and a ground line; and a series connection with the first photocoupler. A first switch element, a second photocoupler having a light-emitting side connected between the other phase of the single-phase commercial power supply and a ground line, and a second switch element connected in series with the second photocoupler The first switch element is turned on in response to an external control signal when detecting a line voltage between one phase of the single-phase commercial power supply and a ground line. On the other hand, the second switch element is turned on in response to an external control signal when detecting a line voltage between the other phase of the single-phase commercial power supply and the ground line. A line voltage between one phase of the single-phase commercial power supply and the ground wire or the single-phase When any one of the line voltages of the other phase of the commercial power supply and the ground wire is a predetermined commercial power supply voltage, the first power supply connected between the corresponding lines is
4. The electric shock prevention device according to claim 3, wherein the light receiving element of the second photocoupler is in a conductive state, and the light receiving element of the other photocoupler is in a non-conductive state. 5. An earth leakage breaker is provided between the high voltage generation means and the power plug, and a potential detection point by the line voltage detection means is located on the upstream side of the earth leakage breaker. The electric shock prevention device according to claim 2 or 4. 6. The electric shock prevention device according to claim 5, wherein the connection point of the line voltage detecting means to the ground side is a ground terminal provided in the high voltage generating means or the high voltage operating means. 7. An ozone sterilizer comprising the electric shock prevention device according to claim 1 or 3, wherein the high-pressure operating means is an ozone generator. Sterilizer.