JPH025259Y2 - - Google Patents

Description

[Detailed description of the invention] (1) Field of application This invention relates to a safety device for combustion appliances in which the detection device is operated by battery power, and includes a built-in CO detection device, a flame detection device, and a safety device. Can be used for combustion appliances.

(2) Prior art and its problems Many appliances and devices using batteries as a power source are used in various fields, but these types of devices do not operate smoothly if the battery power supply voltage drops below a certain level.

Therefore, a so-called battery check, which displays a lamp when the battery voltage drops below a certain level, is incorporated into this type of appliance or device.

However, sufficient safety cannot be ensured simply by incorporating such a battery check with only a display into a combustion appliance.

With conventional battery checks, the battery voltage is only checked and displayed during the starting operation, so if the battery voltage drops during operation of a combustion appliance, etc., the appliance may not operate smoothly.
This is because the safety device itself may become inoperable.

(3) Technical issues This invention solves the problem of combustion appliances in which the detection device is operated using a battery power source and the detection device remains in the detection state even while the appliance is in operation. In order to prevent accidents during operation, the object is to constantly check the battery voltage while the appliance is in operation, and to stop the combustion of the appliance when the voltage falls below a certain level.

(4) Technical means The technical means of the present invention for solving the above problems will be explained according to the principle diagram shown in Figure 1. It is equipped with a safety valve device of the type that closes the inserted solenoid valve 1, and a switch 20 that is in a closed state while the device is in operation is inserted into the power supply circuit to the detection device 2. A voltage check circuit 3 for checking the battery voltage is provided in parallel, and a reverse voltage application circuit 4 is provided for applying a voltage opposite to that during normal operation to the excitation coil 11 of the solenoid valve, and a reverse voltage is applied by the output of the voltage check circuit. This is done by turning on circuit 4.

(5) Effect The above technical means of the present invention operates as follows.

While the appliance is in operation, the voltage check circuit 3 is constantly supplied with electricity by the switch 20, and the battery voltage is constantly checked. When this voltage drops below a certain voltage, the reverse voltage application circuit 4 is turned on by the output from the voltage check circuit 3, and a voltage opposite to that in the steady state is applied to the excitation coil 11 of the safety valve, and the solenoid valve 1 is temporarily turned on. The state is the same as OFF, the valve closes, the gas circuit is cut off, and combustion stops.

(6) Effects Since the present invention has the above configuration, it has the following unique effects.

While the equipment is in operation, the voltage is constantly checked, and when the battery voltage is depleted below the steady state, the safety valve operates safely, thereby preventing accidents caused by voltage drops.

(7) Embodiment The embodiment shown in Fig. 2 is implemented in a water heater, and employs a thermocouple type solenoid valve 1 as a safety valve.When the flame of the burner 12 is extinguished,
The current in the excitation coil 11 of the solenoid valve 1 disappears or drops, and the solenoid valve 1 closes.

Also, the voltage of the battery power source 6 is checked by the voltage check circuit 3.
In this embodiment, the detection device 2 described in the technical means section includes the CO detection circuit 21 and the sensor 21a of the CO detection circuit 21 (incomplete combustion). An element whose resistance decreases as the generated CO concentration increases)
A sensor disconnection check circuit 24 is incorporated to check for disconnection.

Then, the output of the voltage check circuit 3, the second
A reverse voltage applying circuit 4 applies a reverse voltage to the excitation coil 11 for the solenoid valve 1 based on the output of the CO detection circuit 21 via the timer 23 and the output of the sensor disconnection check circuit 24 via the thyristor 61 and the first transistor 62. is now being driven.

Next, the voltage check circuit 3, reverse voltage application circuit 4, etc. will be described in more detail.

ON when water flow occurs in the hot water supply circuit (not shown)
The power supply voltage supplied from the operating water flow switch 20a (corresponding to the switch 20 described in the technical means section) to the CO detection circuit 21 is divided by a first resistor 63 and a second resistor 64. The divided voltage output is applied to the positive input terminal of the first comparator 65. Further, the input terminal on the negative side of the first comparator 65 has a signal that occurs during incomplete combustion of the burner 12.
An output taken from the positive electrode side of the sensor 21a whose resistance value decreases as the CO concentration increases is applied. Note that 96 shown near the first comparator 65 is a pull-up resistor.

Further, the output of the first comparator 65 is sent to the integrating circuit 6.
6 to the positive input terminal of the second comparator 67, and the reference voltage set by the third and fourth resistors 68 and 69 to the negative input terminal of the second comparator 67. Furthermore, the output of the second comparator 67 is applied to the base of the second transistor 42.

Next, the voltage of the battery power supply 6 via the water flow switch 20a described above is applied to the second integration circuit 70 of the first timer 22 shown in the middle part of the figure, and the output of the second integration circuit 70 and the fifth , sixth resistor 72,7
The reference voltage set at No. 3 is compared by a third comparator 71. And the third
The output of the comparator 71 is applied to the gate of the thyristor 61 via a first differentiating circuit 74 and a noise filter 75.

The output taken from the anode side of the thyristor 61 is applied to the base of the first transistor 62, and the collector side output of the first transistor 62 (which is treated as a signal for the sensor disconnection check circuit 24) is The voltage is applied to the base of the second transistor 42 constituting the reverse voltage application circuit 4. Also, the cathode side of the thyristor 61 is turned ON by the output of the sensor disconnection check circuit 24.
A second operative transistor 76 is inserted. The input side of the sensor disconnection check circuit 24 that applies a signal to the second transistor 76 is connected to the output of the sensor 21a constituting the above-mentioned CO detection circuit 21 and the reference voltage (seventh and eighth resistors 77, 78) is provided. Note that the fourth comparator 7
97 shown in section 9 is a pull-up resistor.

Next, the voltage check circuit 3 will be explained. The voltage check circuit 3 compares the third transistor 31 and the output of the transistor 31 with a reference voltage (set by the ninth and tenth resistors 80 and 81). The base voltage of the third transistor 31 is the 11th and 12th comparator.
It is set by resistors 82 and 83. The signal from the fifth comparator 32, which is the output of the voltage check circuit 3 composed of these components, is applied to the second transistor 42.

Now, when you turn on the starting switch (not shown),
Burner 12 is activated by operation of an ignition mechanism (not shown).
starts to burn, the thermocouple 89 is heated, and a thermoelectromotive force is applied from the thermocouple 89 to the excitation coil 11. In this embodiment, the excitation coil 11 is moved in the direction from the bottom to the top (see the solid arrow).
It is configured so that the current flows through it. As a result, during the hot water supply operation, the excitation coil 11 is in a state where "+" is applied to its lower terminal and "-" is applied to its upper terminal, and the excitation coil 11 is thereby excited. The electromagnetic valve 1 is held in an open state by a biasing force of 11.

Further, when the start switch is turned on, the water flow switch 20a is closed and the changeover switch 86 is switched to the ground side as shown by the imaginary line in the figure, and the hot water supply operation proceeds in this state.

During this hot water supply operation, the voltage of the battery power source 6 is applied via the water flow switch 20a which is in the closed state.
CO detection circuit 21 and sensor disconnection check circuit 2
4 Furthermore, the voltage is applied to the voltage check circuit 3, etc., and the CO detection circuit 21 monitors CO generation due to incomplete combustion of the burner 12, and
The sensor disconnection check circuit 24 monitors the sensor 21a constituting the CO detection circuit 21 for disconnection, and the voltage check circuit 3 continues to monitor the voltage of the battery power source 6.

When the amount of electricity stored in the battery power source 6 is sufficient during the hot water supply operation, that is, in a state where the voltage across the battery power source 6 has not dropped, the voltage check circuit 3
The third transistor 31 of is held in the ON state,
As a result, the "L" signal is applied to the "+" terminal of the fifth comparator 32. As a result, the fifth comparator 32 outputs an "L" signal, and the signal is applied to the second transistor 42. That is, the second
Transistor 42 is maintained in an OFF state. In addition to the output of the voltage check circuit 3, the output of the second timer 23 as a delay signal of the CO detection signal and the signal of the first transistor 62 treated as a disconnection signal are applied to the second transistor 42. However, as will be described later, both of these signals are in the "L" state when the instrument is normal.

Therefore, when the battery power supply 6 has a sufficient amount of electricity stored, by maintaining the second transistor 42 in the OFF state, the "+" pole of the battery power supply 6 is excited, as in the case of a power supply voltage drop, which will be described later. The coil 11 is never connected.

Now, when the amount of electricity stored in the battery power source 6 decreases during the hot water supply operation, and the voltage of the battery power source 6 begins to drop, the voltage between the base and emitter of the third transistor 31 decreases, causing the third transistor 31 to become disabled. enters the saturation region, thereby causing the third transistor 31
begins to perform an amplification function.

If the voltage between the base and emitter of the third transistor 31 continues to drop while it is in the unsaturated region, the base current and collector current of the third transistor 31 decrease, and the collector current decreases. Due to this decrease, the amount of voltage drop across the variable resistor 92 inserted into the collector circuit of the third transistor 31 decreases. That is, there is a tendency to pull the output on the collector side of the third transistor 31 toward the "+" side.

From this, even if the voltage of the battery power source 6 begins to drop, the collector side output of the third transistor 31 will not drop much.

On the other hand, the voltage (reference voltage) at the midpoint between the ninth and tenth resistors 80 and 81, which is compared with the collector side output of the third transistor 31, simply drops with the voltage drop of the battery power source 6, and the voltage ( Fifth comparator 32
(reference voltage) decreases faster than the collector side output of the third transistor 31 described above. That is, the collector side output of the third transistor 31 is the ninth,
The voltage becomes relatively high compared to the reference voltage set by the 10 resistors 80 and 81.

Then, the output of the fifth comparator 32 changes to the "H" state, and as a result, the second transistor 42 constituting the reverse voltage application circuit 4 turns ON, and the excitation coil 11 receives voltage from the thermocouple 89. A voltage opposite the voltage is applied. That is, an action occurs in the excitation coil 11 that causes a current to flow downward from above as shown by the imaginary line in the figure through the second transistor 42, and as a result, the excitation coil 11 The current supplied from the thermocouple 89, which used to flow from bottom to top, is suppressed. As a result, the current flowing through the excitation coil 11 decreases or disappears, and the solenoid valve 1 is closed, thereby maintaining the burner 12 in the extinguished state.

In this way, in the case of the above-mentioned device, if the amount of electricity stored in the battery power source 6 decreases and its voltage drops during the operation of the appliance, this can be detected and the burner 12 can be turned off.

Next, the CO detection operation and the disconnection checking operation of the sensor 21a incorporated in the CO detection circuit 21 will be described.

The water flow switch 20a is activated by the hot water supply operation described above.
When a certain period of time has elapsed since the timer 22 closed and the integral output of the second integrating circuit 70 incorporated in the first timer 22 exceeds a predetermined value, the third comparator 71 outputs an "H" signal. , the first differentiating circuit 74 detects the rise of the "H" signal, and the detection signal (output of the first differentiating circuit 74) is transmitted to the thyristor 61.
is applied as a trigger signal to the gate of On the other hand, if the sensor 21a of the CO detection circuit 21 is disconnected and the fourth comparator 79 outputs an "H" signal, the second transistor 76 is in the ON state, so the trigger signal to the thyristor 61 is When the above voltage is applied, the thyristor 61 turns ON, and as a result, an "L" signal is applied to the base of the first transistor 62, which turns it off.
It becomes OFF state. Then, the signal on the collector side of the first transistor 62 goes into the "H" state and is applied to the second transistor 42, whereby a reverse voltage is applied to the excitation coil 11 in the same way as when the battery voltage drops above. The solenoid valve 1 is then closed. In other words, the safe state in which the burner 12 is extinguished is maintained.

Next, the burner 12 is in an incomplete combustion state.
When CO is generated, this causes the sensor 21a to
The resistance of the first comparator 65 decreases, and the "H" signal (CO detection signal) is continuously outputted from the output section of the first comparator 65. When this signal continues for a period of time specified by the integrating circuit 66, the second comparator 67 outputs an "H" signal based on the output from the integrating circuit 66, thereby causing the reverse voltage applying circuit 4 to The constituting second transistor 42 is turned ON. As a result, a back electromotive force is applied to the excitation coil 11, similar to when the voltage of the battery power source 6 drops, and the solenoid valve 1 is closed.

Finally, after the hot water supply operation has finished, turn on the start switch.
When turned off, the changeover switch 86 is switched to the "+" side in conjunction with this, and the water flow switch 20a is turned off with a slight delay. Then, when the changeover switch 86 is switched to the "+" side, a downward current (direction indicated by the imaginary arrow) in the excitation coil 11 in the figure is applied to the battery power supply 6 for a certain period of time defined by the capacitor 87. It will be in a state where it is supplied from. Then, even if the thermocouple 89 has not lost its electromotive force due to residual heat immediately after the burner 12 is extinguished, the solenoid valve 1 is forcibly closed and a perfect state is ensured.

As described above, in the above device, the detection device 2 such as the CO detection circuit 21 and the sensor disconnection check circuit 24 monitors the operation of the appliance, and the battery power source 6 detects voltage drop while the appliance is operating. When there is a possibility that the detection device 2 will no longer function, the voltage check circuit 3 detects the voltage drop in the battery power source 6 and a safe state can be ensured in which the burner 12 is extinguished.

[Brief explanation of the drawing]

Fig. 1 is a drawing explaining the principle of the present invention, and Fig. 2 is an electric circuit diagram of an embodiment of the present invention.
... Solenoid valve, 11 ... Excitation coil, 2 ... Detection device, 20 ... Switch, 20a ... Water flow switch, 3 ... Voltage check circuit, 4 ... Reverse voltage application circuit.

Claims (1)

[Scope of utility model registration request] In a type of combustion appliance in which the detection device is operated using battery power and the detection device remains in the detection state even while the appliance is in operation, the solenoid valve 1 inserted at the most upstream side of the gas circuit is closed in the event of an abnormality. A switch 20, which is equipped with a safety valve device of the valve type, is inserted into the power supply circuit to the detection device 2 and remains closed while the device is in operation, and the battery voltage is checked in parallel with the detection device 2. A voltage check circuit 3 is provided and an excitation coil 11 of the solenoid valve is provided.
A safety device for a combustion appliance, which is equipped with a battery-operated detection device, which is provided with a reverse voltage application circuit 4 that applies a voltage opposite to that in a steady state, and turns on the reverse voltage application circuit 4 by the output of the voltage check circuit.