JP4267960B2 - Water freeze prevention device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water supply freezing prevention device that can detect the presence or absence of disconnection of a heating element by the presence or absence of light emission of a light emitting diode.
[0002]
[Prior art]
As shown in FIG. 2, a conventional water freeze prevention device includes a heating element 101 for heating a water pipe, a power plug 102 for supplying power to the heating element 101, and a power supply from the power plug 102 to the heating element 101. And a thermo switch 103 for switching the power supply stop, and a light emitting diode 104 for displaying that the thermo switch 103 is turned on to supply power to the heating element (being operated). The light emitting diode 104 is connected in series to the resistor 106 and the diode 105 for decompression rectification, and is connected in parallel to the heating element 101 at a position closer to the heating element 101 than the thermo switch 103.
[0003]
The thermo switch 103 is set to switch from the off state to the on state when the temperature is low, for example, 3 ° C. or lower, and to be turned off when the temperature is high, for example, 10 ° C. or higher. By turning on and off the thermo switch 103, power can be supplied to the heating element 101 only at a low temperature at which the water supply may freeze.
[0004]
In addition, since the power is also supplied to the light emitting diode 104 when the thermo switch 103 is on, the light emitting diode 104 emits light. Therefore, by visually observing the light emitting diode 104, it can be confirmed whether or not the water freeze prevention device 100 is in operation.
[0005]
The water supply freezing prevention apparatus of such a structure is disclosed by each following patent document, for example.
[0006]
[Patent Document 1]
JP 11-142464 A [Patent Document 2]
JP-A-11-200431 [Patent Document 3]
JP 2001-124414 A [Patent Document 4]
Japanese Patent Laid-Open No. 2001-295325
[Problems to be solved by the invention]
Here, since the light emitting diode 104 is supplied with power when the thermo switch 103 is turned on, the light emitting diode 104 is lit even when the heating element 101 is disconnected. However, it is easy for the user to misunderstand that the heating element 101 is heated when the light emitting diode 104 is turned on. For this reason, in the winter season, there is a risk that an accident may occur in which the water pipe is ruptured due to the heating element 101 being disconnected and not generating heat even though the water freeze prevention device is provided.
[0008]
In order to prevent such an accident, it is desirable to inspect the heating element 101 for disconnection before the cold season. However, since the thermo switch 103 remains in the off state when the outside air temperature is high, the thermo switch 103 is forcibly cooled and turned on to check whether the heating element 101 is actually heated. is required. Such work is troublesome and troublesome.
[0009]
An object of the present invention is to propose a water supply freezing prevention device capable of confirming the presence or absence of disconnection of a heating element by a simple operation when a thermo switch is in an off state, such as before a season.
[0010]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the water supply freezing prevention device of the present invention is
A heating element for heating the water pipe;
First and second power supply lines respectively connected to both ends of the heating element to supply power to the heating element;
A thermo switch inserted in the first power supply line;
A light emitting diode having one end connected to a position between the thermoswitch and the heating element in the first power supply line;
A switch for selectively connecting the other end of the light emitting diode to either the second power supply line or a position on the power supply side of the thermoswitch in the first power supply line; It is characterized by that.
[0011]
In the water supply freezing prevention device of the present invention, when the other end of the light emitting diode is connected to the second power feeding line by the changeover switch, the light emitting diode is connected between the power feeding lines on the heating element side of the thermo switch. And in parallel connection. In this state, since the light emitting diode blinks in conjunction with the on / off of the thermo switch, it can be confirmed by visually checking the light emitting diode whether the water supply freezing prevention device is operating or stopped.
[0012]
Further, when the other end of the light emitting diode is connected to the position closer to the power supply side than the thermo switch in the first power supply line by the changeover switch, a thermo switch bypass circuit in which the light emitting diode and the heating element are connected in series is formed. In this state, if the heating element is disconnected, the light emitting diode is not turned on. Therefore, the presence or absence of disconnection of the heating element can be confirmed from the presence or absence of lighting of the light emitting diode.
[0013]
Here, in general, the changeover switch normally connects the other end of the light emitting diode to the second power supply line, and the first power supply only when the changeover switch is operated. Configured to switch connections to the line side. In this way, it is only necessary to operate the changeover switch when it is necessary to check the disconnection of the heating element.
[0014]
In general, a light-emitting diode is connected in series with a resistor for pressure rectification and a diode. For example, a diode is connected in series between the light emitting diode and the changeover switch, a resistor is connected in series between the changeover switch and the first power supply line, and between the changeover switch and the second power supply line. It is sufficient to connect resistors in series.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment)
FIG. 1 is a circuit diagram of a water supply freezing prevention apparatus according to an embodiment to which the present invention is applied. A water supply freeze prevention apparatus 1 according to the present embodiment has a heating element 2 for heating a water pipe (not shown), and a pair of power supply lines are connected to the heating element 2 from a power plug 3. Power supply is performed via 4 and 5. A thermo switch 6 is inserted in one power supply line 4 connected to one end 2a of the heating element 2. A cathode-side terminal 7 a of the light-emitting diode 7 is connected to a position between the thermoswitch 6 and the heating element 2 in the power supply line 4. The anode side terminal 7b of the light emitting diode 7 is connected to a changeover switch (disconnection detection switch) 9 via a diode 8 connected in series in the forward direction.
[0016]
The changeover terminal 9 a of the changeover switch 9 is always connected to a contact 10 a connected to the resistor 10, and the other end 10 b of the resistor 10 is connected to the power supply line 5. When an operation unit (not shown) of the changeover switch 9 is pressed, the changeover terminal 9 a is switched to the other contact 11 a side connected to the resistor 11. The other end 11 b of the resistor 11 is connected to a position on the power supply side with respect to the thermoswitch 6 in the power supply line 4. When the pressing of the changeover switch 9 is released, the changeover terminal 9a returns to the contact 10a side again.
[0017]
The thermo switch 6 is set to operate so as to be switched from the off state to the on state when the temperature is low, for example, 3 ° C. or lower, and to be turned off when the temperature is high, for example, 10 ° C. or higher.
[0018]
Operation | movement of the water supply freeze prevention apparatus 1 of this example is demonstrated. The changeover terminal 9a of the changeover switch 9 is connected to the contact 10a. In this state, when the outside air temperature decreases and the thermo switch 6 is turned on, a heating element feeding circuit is formed via the feeding line 4, the thermo switch 6, the heating element 2 and the feeding line 5, and the heating element 2 is fed to generate heat. The water pipe is then heated to prevent its freezing.
[0019]
In this state, a light-emitting diode power supply circuit passing through the power supply line 5, the resistor 10, the changeover switch 9, the diode 8, the light-emitting diode 7 and the power supply line 4 is also formed. 4 and 5 are connected. Accordingly, since the light emitting diode 7 is turned on, it can be confirmed that the water supply freezing prevention device 1 is in an operating state.
[0020]
Next, when the changeover switch 9 is operated, the changeover switch 9 is switched to the resistor 11 side. As a result, a power feeding circuit is formed via the power feeding line 4, the resistor 11, the changeover switch 9, the diode 8, the light emitting diode 7, the heating element 2, and the power feeding line 5. That is, the light emitting diode 7 and the heating element 2 are connected in series with the thermoswitch 6 bypassed.
[0021]
In this state, when the heating element 2 is not disconnected and is normal, power is supplied to the heating element 2 and the light emitting diode 7, the heating element 2 generates heat and the light emitting diode 7 is lit. However, when the heating element 2 is disconnected and does not generate heat, power is not supplied to the light emitting diode 7 and the light emitting diode 7 is not lit. Therefore, it can be confirmed whether the heating element 2 is normal or disconnected by observing whether or not the light emitting diode 7 is turned on when the changeover switch 9 is pressed.
[0022]
【The invention's effect】
As described above, the water supply freezing prevention device of the present invention includes a change-over switch for detecting disconnection of the heating element. By operating this change-over switch, the thermo-switch is bypassed with the light emitting diode. A power feeding circuit in which heating elements are connected in series is formed. Therefore, the presence or absence of disconnection of the heating element can be confirmed based on whether or not the light emitting diode is turned on.
[0023]
Therefore, according to the present invention, the presence or absence of disconnection of the heating element can be confirmed only by a simple operation of pressing the changeover switch even in a state where the thermo switch is not turned on, for example, in a state other than winter.
[Brief description of the drawings]
FIG. 1 is a circuit diagram of a water supply freezing prevention apparatus according to an embodiment of the present invention.
FIG. 2 is a circuit diagram of a conventional water supply freezing prevention device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Water supply freezing prevention apparatus 2 Heat generating body 3 Power plug 4, 5 Feed line 6 Thermo switch 7 Light emitting diode 8 Diode 9 Switch 9a Switch terminal 10, 11 Resistor 10a, 11a Contact point of switch

Claims (3)

A heating element for heating the water pipe;
First and second power supply lines respectively connected to both ends of the heating element to supply power to the heating element from a power plug;
A thermo switch inserted in the first power supply line;
A light emitting diode having one end connected to a position between the thermoswitch and the heating element in the first power supply line;
A switch for selectively connecting the other end of the light emitting diode to either the second power supply line or a position on the power supply side of the thermoswitch in the first power supply line; Water freeze prevention device. In claim 1,
The changeover switch normally connects the other end of the light emitting diode to the second power supply line, and the connection is switched to the first power supply line only when the changeover switch is operated. Water freezing prevention device characterized by that. In claim 1 or 2,
A diode is connected in series between the light emitting diode and the changeover switch,
A water resistance freeze prevention device, wherein a resistor is connected in series between the changeover switch and the first power supply line, and a resistor is also connected in series between the changeover switch and the second power supply line. .

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