JPH02608B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a combustion safety device that automatically shuts off gas when a gas combustion appliance misignites or misfires.

Conventional configurations and their problems In recent years, gas stoves and table stoves with a safety function that automatically shuts off the gas to prevent raw gas from leaking in the event of ignition error or misfire have begun to appear on the market. Figure 1 shows an example of a conventional gas stove. Gas flows in from inlet 1, passes through safety valve 2 and gas tank 3, and is fired at burner 4 by an igniter (not shown).
ignites and burns. 5 is a sensor for detecting the presence or absence of flame in the burner 4, which uses a thermocouple type thermoelement.

The safety valve 2 has a structure in which a thermoelectromotive force generated by the thermoelement 2 energizes an electromagnet to attract the valve. Generally, in order to ignite the burner 4, a user turns the knob 3 to flow gas and operate an igniter (not shown), and also pushes the knob 3 to open the safety valve 2 and press the iron piece of the safety valve 2 against the electromagnet. As the burner 4 is ignited and the flame heats the element 5, an electromotive force is generated and the safety valve 2 continues to open. When the burner 4 misfires for some reason, the electromotive force of the element 5 disappears, and the safety valve 2 becomes unable to attract and closes the valve due to the force of the internal spring.

In this case, when opening the safety valve 3, it is necessary to press the safety valve 3 at the same time, and the time required for the burner 4 to ignite and the element 5 to generate an electromotive force (approximately 30 to 40 seconds) is required. It becomes inconvenient to use because you have to keep pressing it. Further, when there are three or four burners 4 as in a gas table stove, the system shown in FIG. 1 is required for the number of burners, making the structure complicated and expensive.
Furthermore, since the electromotive force of the element 5 is normally as low as several tens of mV, it is necessary to make the attraction surface between the electromagnet and the iron piece of the safety valve 2 highly precise, which causes problems such as poor manufacturing efficiency.

Purpose of the Invention The present invention improves the above-mentioned conventional problems, and provides a safety device that eliminates gas leakage in the event of burner misfire or non-ignition without reducing the operability of the appliance. With the goal.

Composition of the Invention In order to achieve the above object, the present invention includes a combustion sensor that detects the combustion flame of a burner, a safety valve that opens in front and self-maintains, a gas cock and a switch mechanism connected thereto, and a safety control section. The safety control section includes a closing drive section that outputs a signal to close the safety valve when there is no flame after a certain period of time has passed after opening the gas tank, a first notification section that notifies when the valve is closed, and a gas tank switch mechanism. The present invention has a configuration including a check operation part that checks whether the safety valve is open when a signal indicating that the gas stock is open is input from the valve, and a second notification part that gives notification in response to the signal from the check operation part.

DESCRIPTION OF EMBODIMENTS Examples of the present invention will be described below with reference to FIGS. 2 to 8.

FIG. 2 shows an embodiment of the combustion safety device of the present invention. The gas passes through an inlet 1, a safety valve 6 and a gas tank 3, which will be explained later, and is burned in a burner 4. At this time, the gas tank 3 may be in the shape of a valve. The flame is detected by a combustion sensor 7 and sends a signal to a safety control section 8. The safety control unit 8 operates the safety valve 6 in response to a signal from the combustion sensor 7 and a gas switch 9 which generates an opening/closing signal for the gas tank 3 in conjunction with the combustion sensor 7 .
Outputs a signal to. Reference numeral 10 indicates a DC power source that drives the safety control section 6.

FIG. 3 shows an example of the safety valve 6.

Here, a self-adsorption type safety valve is shown using a permanent magnet 11. Normally, the valve 12 is pressed against the valve seat 14 by a spring 13 to prevent gas from flowing from the A chamber to the B chamber. By pressing the external button 15, the valve 12 causes the gas leaving the valve seat 14 to flow from the A chamber to the B chamber. When the plunger 16 made of a magnetic material contacts the magnetic yoke 17, a magnetic circuit is formed between the permanent magnet 11, the yoke 17, and the plunger 16, and the plunger 16 is connected to the spring 13.
The valve 12 continues to open even if the force of the button 15 is overcome and the pressure of the button 15 is applied. Here coil 1
When a direct current is applied to 8 that generates a magnetic field in a direction that cancels the magnetic force of the permanent magnet, the attraction force disappears, and the force of the spring 15 causes the valve 12 to close to the valve seat 14.
Pressure prevents gas from entering. The safety valve as described above makes it possible to close the safety valve 6 when the safety control section 8 in FIG. 2 detects an abnormality.

In addition, this type of safety valve does not require constant energization to open the valve 12, but only requires instantaneous energization to close the valve, so it can withstand long-term use even if the DC power source 10 is a dry battery. The safety valve 6 may have a ratchet type construction as shown in FIG.

With the configuration shown in FIG. 2, the safety control section 8 detects that the pot 3 is opened by the pot switch 9, and outputs a signal to close the safety valve 6 if there is no signal from the combustion sensor 7 at this time. Combustion sensor 7
Possible options include those that detect the temperature of the flame and those that detect the ionic current of the flame. Here, as in FIG. 1, an example of a thermoelement using a thermocouple will be explained.
Generally, this type of temperature sensor has a thermal time constant, and even if the burner 4 is ignited, there is a delay time until the sensor 7 outputs an output. It has a timer section that does not shut off the safety valve 6 even if there is no signal from the sensor 7 for a certain period of time.

Gas stoves often have two to four burners. Figure 5 shows the case of a stove with three burners. One safety valve 6 is provided on the gas inlet 1 side. The safety control unit 8 controls each burner 4a to 4.
The safety valve 6 is checked only when the output of the combustion sensor 7a of the burner 4a whose switch is open is checked, and the output of the combustion sensor 7a of the burner 4a whose switch is open is checked. It operates so as not to shut off even if there is no sensor output. Further, here, when a switch open signal is input from any of the switches 9a to 9c, a signal for driving the external ventilation fan 19 is outputted to perform ventilation. Furthermore, since the safety valve 6 is a self-adsorption valve, it continues to open even if the safety control section 8 does not operate, and even if the burner misfires at this time, the valve cannot be shut off. When the DC power supply 10 is configured with a dry battery, a drop in battery voltage is detected and the safety valve 6 is automatically activated before the voltage reaches the limit at which the safety valve 6 operates.
output to cut off the At the same time, when a signal to open the door is input from each switch, it is detected that the power source 10 is at a voltage that allows the safety valve 6 to operate, and the buzzer 20 notifies the operator. For example, if there is no power source 10, there will be no buzzer notification, so the user can determine this.

Furthermore, the buzzer 20 also functions to notify a person by giving a warning for a certain period of time even when the safety valve 6 is shut off. Further, even if the pots 3a to 3c are opened while the safety valve 6 is closed, the burner will not be lit no matter how long it takes because gas will not flow. In order to prevent this, a configuration is adopted in which it is detected whether the safety valve 6 is open or closed when the locks 3a to 3c are opened, and a buzzer 20 is used to notify even when the safety valve 6 is closed.

FIG. 6 shows the configuration of the safety control section 8. The safety control section 8 includes a microcomputer 21, a sensor input circuit 22, a switch input circuit 23, a battery check circuit 24, a valve drive circuit 25, a valve check circuit 26, a buzzer drive circuit 27, and a ventilation fan drive output circuit 28.

The sensor input circuit 22 includes combustion sensors 7a to 7c.
(Here, a thermocouple type thermoelement) output is compared with an internal reference potential, and whether or not each burner is in combustion is input to the microcomputer 21.

The switch input circuit 23 detects the state of each of the switches 9a to 9c, and inputs to the microcomputer 21 whether the switches 3a to 3c are open or closed. Here, when the switch 3 is closed, the NC contact of the switch 9 is connected to the ground, and when the switch 3 is open, the NO contact is connected to the ground. At this time, the negative terminal of the battery 10 is connected to the NO contact, so that when any of the terminals is opened, the battery 1 is connected to the ground terminal of the safety control section 8.
The negative terminal of 0 is connected to supply power, and it serves both as a power switch and a power switch.

A battery check circuit 24 detects the voltage of the battery 10 and sends a signal to the microcomputer 21 when the voltage falls below a certain level. In response to this, the microcomputer 21 shuts off the safety valve 6 and drives the buzzer 20.

The valve drive circuit 25 is a microcomputer 2
The signal from 1 is amplified and the coil 18 of the safety valve 6 is momentarily energized to shut off the safety valve 6.

The valve check circuit 26 is a circuit that checks whether the safety valve 6 is in the open or closed state and sends a signal to the microcomputer 21. In order to provide the valve check function, a contact that interlocks with the safety valve 6 is required. Alternatively, a configuration in which detection is performed based on a difference in impedance flowing through the coil 18, or the like may be used.

The buzzer drive circuit 27 is a circuit that drives the buzzer 20 and includes an oscillator therein, and oscillates on and off based on the output of the microcomputer 21. Here, the buzzer drive circuit 27 may be configured to provide notification using a lamp.

The ventilation fan drive output circuit 28 is a circuit that outputs a signal to automatically operate the ventilation fan 19 when the cock 3 is opened.The output from the microcomputer 21 drives a relay or the like to operate the ventilation fan 19.

FIG. 7 shows a specific example of the circuit shown in FIG. Parts that are the same as those in FIG. 6 are designated by the same numbers. The valve check circuit 26 is configured to detect a contact 6' connected to the safety valve 6. OSC 29 is an oscillator that generates a reference clock signal for microcomputer (CPU) 21.

FIG. 8 shows an example of a flow chart of the basic program of the microcomputer 21. Here, an example is given in which there is one burner 4, but the same concept may be applied even if there are a plurality of burners. In the figure, the ignition timer W is used to cover the response delay of the combustion sensor, and operates after the cock is opened, during which time the input from the sensor is ignored. The ``buzzer 0.2sec'' output of the X is the third notification part that checks whether the battery voltage is sufficient when each door is opened and sounds the buzzer for 0.2 seconds each time it is ready for operation. This can be determined by not notifying you when the voltage is not high enough to drive the buzzer or when you forget to insert the battery.

"Continuous buzzer" in Y indicates a second notification section that notifies you until the safety valve is opened when the safety valve is closed when the lock is opened. "Buzzer 10sec" in Z indicates the first notification section that notifies when the safety valve performs a shutoff operation.

Although the example in which a microcomputer is used in the safety control section 8 has been described above, the safety control section 8 may be constructed using a discrete circuit. Further, the self-holding mechanism of the safety valve 6 may be configured to hold the safety valve 6 by passing a small current through the electromagnetic coil of the electromagnetic adsorption valve.
In this case, the operation of the closing drive section is such that the valve is closed by a spring force by stopping the current flowing through the electromagnetic coil, but even with this configuration, exactly the same effect as the present invention can be obtained.

The above embodiment has the following effects.

(1) Even if there are multiple gas burners, only one safety valve is required, resulting in an inexpensive and simple system configuration.

(2) Since the system is configured to use a buzzer to notify you of various conditions, the user can check the status even if he or she is far away.

(3) It is a fail-safe and safe system with functions to check the opening/closing of the safety valve and check for battery voltage drop.

(4) It also outputs a signal to automatically operate the ventilation fan, so the air is always kept clean.

Effects of the Invention As explained above, the combustion safety device of the present invention has the following effects.

(1) The safety valve has a self-holding mechanism, so once it is opened, it will remain open until a signal is input from the safety control unit. Furthermore, a timer device is configured to not check for abnormalities until the flame and combustion sensor signals become stable. Therefore, the user only has to open the gas bottle, and there is no need to press and hold the gas bottle, making it a one-touch operation, which is convenient to use.

(2) The check operation unit checks the state of the safety valve when the lock is opened, and notifies you when the safety valve is closed.
The open/closed state of the safety valve can be easily confirmed, and it can be determined that the safety valve needs to be opened.

(3) Since the safety valve has a self-holding mechanism, no electricity is required to open and hold the valve, which saves power and can be used as a battery power source.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a conventional combustion safety device, Fig. 2 is a block diagram showing an embodiment of the combustion safety device of the present invention, and Figs. 3 and 4 are block diagrams showing an example of a safety valve in the same device. , Fig. 5 is a block diagram showing another embodiment of the same device, Fig. 6 is a block diagram showing the structure of the safety control section in the same device, Fig. 7 is a circuit diagram showing a specific example thereof, and Fig. 8 is a block diagram showing the configuration of the safety control section in the same device. It is a flow diagram when a microcomputer is used in the same circuit. 3, 3a, 3b, 3c... Gaskotok, 4, 4
a, 4b, 4c...burner, 6...safety valve, 7,
7a, 7b, 7c... Combustion sensor, 8... Safety control section, 9, 9a, 9b, 9c... Kotuku switch (switch mechanism), 10... DC power supply (dry battery),
11...Permanent magnet (self-holding mechanism), 12...Valve,
17... Ventilation fan (ventilation device), 18... Electromagnetic coil (closing drive unit), 20... Buzzer, 24... Battery check circuit (power supply check unit), 26...
...Valve check input circuit (check operation part),
W...Ignition timer (timer section), X...Third notification section, Y...Second notification section, Z...First notification section.

Claims (1)

[Scope of Claims] 1. A burner that burns gas, a combustion sensor that detects the combustion flame of the burner, a gas tank provided in a gas passage leading to the burner, a safety valve provided on the upstream side of the gas tank, and the a safety control section that drives the safety valve in response to a signal from a combustion sensor, and the safety valve includes a self-holding mechanism for manually opening and holding a valve that opens and closes the gas passage; The safety control unit has a timer unit that operates when the gas tank opens in response to a signal from a switch mechanism that operates in conjunction with each gas tank. If the burner misfires or is in a non-ignition state upon receiving a signal from the combustion sensor after the operation of the burner is completed,
a first notification section that outputs a signal to the closing driving section of the safety valve and notifies the same; and a check that checks whether the safety valve is open when a signal indicating that the gas tank is open is input from a switch mechanism of the gas tank. A combustion safety device configured to include an operating section and a second notification section that provides notification in response to a signal from the check operating section. 2. The combustion safety device according to claim 1, wherein the safety control section includes a power supply check section that closes the safety valve when the voltage of the power supply that drives the safety valve drops below a certain level. 3. The power supply check section is configured to include a third notification section that detects and notifies that the voltage of the power supply is above a certain level when any gas stock is opened based on a signal from the switch mechanism of the gas stock. Combustion safety device according to scope 1.