JP2002174422A - Control circuit for latch solenoid valve of gas cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control circuit for a latch solenoid valve of a gas cooker which securely closes the valve even with interruption of a main power supply and lowering of voltage and further even with any trouble of a main control circuit. SOLUTION: In a gas cooker which comprises a latch solenoid valve driving circuit 15 for driving a latch solenoid valve 11 and a main control circuit 4 for controlling the operation of an entire cooker, there is provided a sub power supply 18 independently from a main power supply 78 of the main control circuit 4, by which the latch solenoid valve driving circuit 15 is closed. Even with power interruption of the main power supply 7, lowering of voltage, ad failure of the main control circuit 4 the latch solenoid valve driving circuit 15 is operated to a safe side, and is automatically closed for fire extinguishment. Further, the main control circuit 4 monitors the sub power supply 18 and disables the gas cooker in trouble, and further detects disconnection of a coil 12 and failures of respective switching elements for opening and closing valves, and stores contents of the failures in a trouble detection storage memory 17 to disable reuse of the cookers, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control circuit for a gas cooking appliance, and more particularly to a control circuit for a latch electromagnetic valve of a gas cooking appliance in which a latch solenoid valve is mounted on a main valve of a gas passage.

[0002]

2. Description of the Related Art A conventional gas cooking appliance will be described below with reference to the drawings. Conventionally, this type of gas cooking appliance uses an electromagnetic valve as a main valve in a gas passage.

FIG. 4 is a circuit diagram showing a configuration of a control circuit of a gas cooking appliance using a conventional solenoid valve. In FIG. 4, the solenoid valve 1 is composed of two parts, an adsorption coil 1a and a holding coil 1b.
Is provided.

When the gas cooking appliance is ignited, the suction driver 2a is turned on by a signal from the port 4a of the microcomputer 4 via the transistor 3a. After that, a pulse signal of 80 Hz is output from the port 4b, and 8
The suction driver 2b and the holding driver 6 are turned on by the 0 Hz rectifier circuit 5 via the transistor 3b. By the above operation, the voltage Vcc of the main power supply 7 is applied to the attraction coil 1a and the holding coil 1b, and the solenoid valve 1 is opened. After the valve is opened, the suction driver 2a is turned off by time control, and the valve is continuously opened only by applying a voltage to the holding coil 1b.

When the solenoid valve 1 is turned off, the port 4b
Is turned off, no voltage is applied to the holding coil 1b of the solenoid valve 1 and the solenoid valve 1
Is closed.

In the failure detection, when the suction driver 2a is turned on at the time of ignition, if the suction driver 2b is in the ON state, a voltage is detected at the port 4c. The operation of the cooking appliance is stopped, and the use of the gas cooking appliance is disabled. Further, when the suction driver 2a is turned off by time control after the valve is opened, the voltage is detected at the port 4c even in the case of a failure in which the suction driver 2a is in the on state. Is stopped, and the use of the gas cooking appliance is disabled.

When the holding driver 6 is in the ON state when the valve opening operation is not being performed and the valve is not continuously opened,
Since the voltage is detected at the port 4d, use of the gas cooking appliance is immediately disabled after the detection, and the gas to the burner 10 is shut off by the gas flow control valve 9 provided in the gas passage 8.

Regarding the disconnection of the suction coil 1a and the holding coil 1b and the failure in which the suction driver 2a, the suction driver 2b and the holding driver 6 are off, no gas is emitted because the solenoid valve 1 does not open. , Do not ignite,
The operation of the gas cooking appliance is stopped by the detection of misfire.

[0009]

In such a conventional gas cooking apparatus using an electromagnetic valve, a voltage must be continuously applied to the holding coil 1b when the valve is continuously opened. The battery is quickly consumed, lacks power saving properties, and requires frequent battery replacement, which is inconvenient. Further, since there are the suction coil 1a and the holding coil 1b, the cost is high and the economy is low.

On the other hand, even if a latch solenoid valve having no holding coil is used for realizing power saving and economy, there are the following problems.

When the valve is closed, the valve is closed by applying a voltage to the coil. Therefore, the valve cannot be closed at the time of a power failure or a drop in the voltage of the battery power supply, and therefore the gas cooking appliance cannot be extinguished.

Even if a backup power supply is provided for closing the valve, it cannot be used in the event of a failure.

If the drive circuit is controlled by a microcomputer, the gas cooking appliance cannot be extinguished because the valve closing operation cannot be performed at the time of a power failure or a drop in the voltage of the battery power supply.

Further, when the valve closing operation becomes necessary during the valve opening operation, there is a moment when the valve closing operation and the valve opening operation occur simultaneously, so that the gas cooking appliance is extinguished without the valve closing operation. May not be possible.

[0015] If a voltage cannot be applied to the coil due to disconnection failure of the coil or disconnection of the lead wire to the coil, the valve cannot be closed and the gas cooking appliance cannot be extinguished.

Further, even if the switch element for applying voltage to the coil when the valve is closed is normal, if the switch element for applying voltage to the coil is open when the valve is open, the valve closing operation is performed. Also, the gas cannot be closed because the voltage is applied to the valve opening side and the valve cannot be closed.

In order to ensure safety, it is necessary to confirm the valve closing operation even when the valve is opened. However, when the valve closing operation is performed, the valve is closed, and the combustion state of the gas cooking appliance is extinguished.

Further, it is very difficult to confirm the disconnection failure of the coil and the short-circuit failure and the open failure of the switch element for applying a voltage to the coil at the HI level and the LOW level of the voltage.

Further, when the valve closing driver fails, the voltage cannot be applied to the coil, so that the valve cannot be closed and the gas cooking appliance cannot be extinguished.

In the solenoid valve, since the valve is opened when voltage is applied and is closed when voltage is turned off, indirect state detection is possible only by monitoring the voltage applied to the coil. Since it is difficult to detect the state with the valve,
If the valve is not closed even after performing the valve closing operation, the latch solenoid valve does not extinguish the fire, and there is a state in which the safety of the gas flow control valve is interrupted by only one valve, which lacks safety.

Further, even if a failure is detected, if the battery is removed or a power failure occurs, the memory of the failure detection is lost.
The gas flow control valve can be used again, and a state in which the gas passage is shut off with only one gas flow control valve, which lacks safety, occurs.

The present invention solves the above problems,
An object of the present invention is to provide a control circuit for a latch electromagnetic valve of a gas cooking appliance, which secures safety and establishes redundancy while using a latch electromagnetic valve.

[0023]

Means for Solving the Problems Claims 1 to 3
The present invention according to the present invention comprises a sub-power supply separately from the main power supply, the main control circuit monitors whether the sub-power supply is normal, and applies a voltage in the valve closing direction when closing the latch solenoid valve. A control circuit for a latch solenoid valve of a gas cooking appliance, wherein a valve closing operation is performed by the sub power supply when a control signal from a main control circuit relating to energization of a switch element is off.

According to the present invention, since the latch solenoid valve is driven by the auxiliary power supply, the valve closing operation can be reliably performed even if there is an abnormality such as a power failure in the main power supply. The valve closing operation is performed when the control signal from the main control circuit according to (1) is OFF, and the valve closing operation can be automatically performed as a safe operation when there is an abnormality in the main control circuit. Also, if an abnormality occurs in the sub power supply,
It can be stopped before the operation of the gas cooking appliance.

According to a fourth aspect of the present invention, the main control circuit turns off a control signal to a latch solenoid valve driving circuit related to energization of a switch element for applying a voltage in an opening direction to the latch solenoid valve. Instruct the valve closing operation after turning off the switch element, and the latch solenoid valve drive circuit turns off the switch element itself prior to the valve closing operation when instructed by the main control circuit to perform the valve closing operation. It is a control circuit of the latch solenoid valve of the gas cooking appliance according to the third aspect.

According to the present invention, there is no moment when the valve closing operation and the valve opening operation are simultaneously performed, and the valve closing operation can be reliably executed. According to the third aspect of the present invention, when the main control circuit instructs the valve closing operation by turning off the control signal related to the energization of the valve closing switch element, the latch solenoid valve driving circuit itself is controlled by the time constant circuit. With the configuration in which the valve-opening switch element is turned off prior to the valve closing, the valve closing operation can be reliably executed automatically when the main control circuit is abnormal.

According to a fifth aspect of the present invention, there is provided a method for detecting a disconnection of a coil of a latch solenoid valve, a failure of a switch element for opening a valve, and a failure of a switch element for closing a valve. Control of the latch solenoid valve of the gas cooking appliance, in which the main control circuit constantly monitors the voltage signal at the intermediate potential between the HI level and the LOW level before and during the operation of the gas cooking appliance by flowing the current. Circuit.

According to the present invention, it is possible to discover when one component has failed, and when a component has failed, the gas flow control valve shuts off the gas passage and disables the use of the gas cooking appliance, thereby establishing redundancy. And secure safety. Further, even when the latch solenoid valve is open, it is possible to detect disconnection of the coil and abnormality of the switch element related to the valve closing operation without actually closing the valve.

According to a tenth aspect of the present invention, when the gas cooking appliance is extinguished, the gas flow control valve is set to the minimum flow position after the latch solenoid valve is closed, and the combustion detection circuit is used. Check the presence or absence of combustion, and when igniting gas cooking equipment, set the gas solenoid valve to the ignition position with the latch solenoid valve closed, perform ignition, and use the combustion detection circuit to determine whether or not combustion has occurred. 5 is a control circuit of the latch solenoid valve of the gas cooking appliance for checking the above.

According to the present invention, when combustion is confirmed in the combustion detection step, the latch solenoid valve is not closed due to a failure, and immediately after closing the gas flow control valve,
Disable the use of gas cooking appliances and ensure safety.

The present invention according to claim 12 uses a failure detection storage memory that is stored without power supply,
4 is a control circuit of a latch solenoid valve of a gas cooking appliance which stores a failure detection.

According to the present invention, the storage of the failure detection is not lost even when the battery is removed or the power failure occurs, so that the gas cooking appliance cannot be used again and the safety is ensured.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the present invention, there is provided a latch solenoid valve driving circuit for driving a latch solenoid valve for opening and closing a gas passage, and a gas flow rate installed in series downstream of the latch solenoid valve. A gas flow rate regulating valve driving circuit for driving a gas flow rate regulating valve, a combustion detection circuit for detecting combustion, a main control circuit for controlling the overall operation, and a main power supply for supplying power to the main control circuit. And another auxiliary power supply, and the latch solenoid valve drive circuit is a control circuit for a latch electromagnetic valve of the gas cooking appliance configured to perform a valve closing operation by the auxiliary power supply.

In the present invention, an auxiliary power supply is provided separately from the main power supply of the main control circuit, and the auxiliary power supply is used for the closing operation of the latch solenoid valve. Therefore, the closing operation of the latch solenoid valve can be reliably performed even when the power supply of the main power source is interrupted or the battery voltage is reduced. In the embodiment, the sub-power supply uses a capacitor charged by the main power supply of the main control circuit. In the embodiment, the valve opening operation is also performed by the auxiliary power supply, but the invention is not limited to this.

According to a second aspect of the present invention, the main control circuit is a control circuit for a latch solenoid valve of a gas cooking appliance according to the first aspect, which detects a failure of a sub power supply.

In the present invention, in which the valve closing operation is performed by the auxiliary power supply, if the auxiliary power supply fails, the valve closing operation of the latch solenoid valve cannot be performed. In the embodiment, the main control circuit detects the failure of the sub power supply by monitoring the time when charging the capacitor and the voltage drop time of the sub power supply when turning off the switch element that charges the capacitor. When a failure is detected, the gas passage is shut off by the gas flow control valve, and then the use of the gas cooking appliance is disabled to ensure safety.

According to a third aspect of the present invention, the main control circuit closes by turning off a control signal to the latch solenoid valve driving circuit related to the energization of a switch element for applying a voltage in the closing direction to the latch solenoid valve. 3. The gas according to claim 1, wherein a valve operation is instructed, and the latch solenoid valve driving circuit turns on the switch element to perform a valve closing operation when the control signal from the main control circuit is turned off. It is a control circuit of the latch solenoid valve of the cooking appliance.

In the present invention, the main control circuit instructs a valve closing operation by turning off a control signal related to energization of a switch element for applying a voltage in the valve closing direction to the coil of the latch solenoid valve. Therefore, the latch solenoid valve drive circuit can execute the valve closing operation as a safe operation even when the control signal is lost due to an abnormality in the main control circuit. In the embodiment, in the latch solenoid valve drive circuit, a circuit configuration of a bias setting that normally turns on the switch element for valve closing is used, and when there is no control signal from the main control circuit, the switch element is inevitably turned on. The valve closing operation is automatically performed even when a signal is not output due to a failure of the main control circuit.

The turning off of the control signal corresponds to a LOW level in a normal positive logic configuration. When this switch element is turned off, the main control circuit is set to 80 Hz.
Is output, and the bias is turned on by a voltage obtained by rectifying the voltage by an 80 Hz rectifier circuit, and the pulse is turned on. Usually, when the main control circuit is abnormal, the port output is at the LOW level. However, in some cases, the HI level may be present. Therefore, a series capacitor is provided in the 80 Hz rectifier circuit to prevent the HI level output. . This 80
One of the reasons for using the Hz pulse is that the capacitor can be inserted.

According to a fourth aspect of the present invention, the main control circuit turns off a control signal to the latch solenoid valve drive circuit related to the energization of a switch element for applying a voltage in the opening direction to the latch solenoid valve. Instruct the valve closing operation after turning off the switch element, and the latch solenoid valve drive circuit turns off the switch element itself prior to the valve closing operation when instructed by the main control circuit to perform the valve closing operation. It is a control circuit of the latch solenoid valve of the gas cooking appliance according to the third aspect.

In the present invention, the main control circuit turns off the switch element for valve opening prior to the closing operation of the latch solenoid valve, and thereafter controls the valve closing operation. Also,
In the event that control becomes impossible due to an abnormality in the main control circuit, for example, the microcomputer is removed, the latch solenoid valve drive circuit responds to the fact that the control signal from the main control circuit is off due to a delay circuit using a capacitor. The switch element for opening the valve itself is turned off prior to automatically proceeding the valve closing operation. In any case, the valve closing operation is performed after the valve opening switch element is surely turned off. Therefore, since the valve opening operation and the valve closing operation do not work instantaneously at the same time, the valve closing operation is surely performed.

In the embodiment, a latch solenoid valve driving circuit capable of coping with an abnormality of the main control circuit is provided with a bias-setting circuit configuration in which a valve-opening switch element is normally turned off. (LOW level), the switch element for valve opening is turned off prior to the valve closing operation by the delay circuit by the capacitor, and thereafter, the switch element for valve closing is turned on after a delay, and the valve closing operation is performed. It is configured to execute. When the main control circuit is normal, it goes without saying that the switch element for opening the valve is forcibly turned off before closing the valve without relying on the above operation. In addition, when the main power supply fails, the switch element for opening the valve is naturally off.

According to a fifth aspect of the present invention, in the first to fourth aspects, the main control circuit detects disconnection of the coil of the latch solenoid valve before and during the operation of the gas cooking appliance. 3 is a control circuit of a latch solenoid valve of the gas cooking appliance according to any one of the embodiments.

In the present invention, the main control circuit always monitors the disconnection of the coil of the latch solenoid valve by a voltage signal before and during the operation of the gas cooking appliance, and after detecting the disconnection, opens the gas passage by the gas flow regulating valve. After shutting off, use of gas cooking appliances will be disabled and safety will be ensured.

According to a sixth aspect of the present invention, in the fifth aspect, the main control circuit detects a disconnection failure of the coil of the latch solenoid valve based on a potential between the HI level and the LOW level of the main power supply. It is a control circuit of the latch solenoid valve of the gas cooking appliance concerned.

In the present invention, the main control circuit detects disconnection of the coil of the latch solenoid valve at a potential intermediate between the HI level and the LOW level. This means is a reasonable detection means when the main control circuit is constituted by a microcomputer. In this embodiment, one end of the coil of the latch solenoid valve is connected to the positive terminal of the main power source via a resistor, and the other end is connected to the negative terminal via a resistor. The presence / absence of disconnection is detected based on whether or not the voltage Vcc is a potential obtained by resistance division by the resistor. At this time, the switch element for opening the valve and the switch element for closing the valve are both off. Also, needless to say, the current flowing through the latch solenoid valve is made very small by the resistance connection, and the operation is not performed only by the resistance.

According to a seventh aspect of the present invention, the main control circuit detects a failure of the switch element for applying a voltage to the coil of the latch solenoid valve.
7 is a control circuit of the latch solenoid valve of the gas cooking appliance according to any one of the above.

In the present invention, the main control circuit confirms the operation of the valve opening switch element and the valve closing switch element in the latch solenoid valve drive circuit, and when a failure is detected, the gas control valve controls the gas flow. After blocking the aisle, disable the use of gas cooking appliances and ensure safety.

According to an eighth aspect of the present invention, the main control circuit detects a failure of the switch element for applying a voltage to the coil of the latch solenoid valve based on the potential between the HI level and the LOW level of the main power supply. It is a control circuit of the latch solenoid valve of the gas cooking appliance according to claim 7.

In the present invention, the main control circuit detects whether or not the operation of the switch element for opening the valve and the operation of the switch element for closing the valve are normal, based on an intermediate potential between the HI level and the LOW level. This means is a reasonable detection means when the main control circuit is constituted by a microcomputer. In the embodiment, one end of the coil of the latch solenoid valve is connected to the plus side of the main power supply via a resistor, the other end is connected to the minus side via a resistor, and the switch element connecting the coil to the plus side of the main power supply is turned on. At this time, whether or not the coil is normal is detected based on whether or not the positive potential of the coil is Vcc. Other switch elements can be similarly formed.

According to a ninth aspect of the present invention, the main control circuit detects a failure in the closing operation of the latch solenoid valve drive circuit without shutting off the gas passage even when the latch solenoid valve is open. A control circuit for a latch solenoid valve of a gas cooking appliance according to any one of claims 1 to 8.

In the present invention, the main control circuit detects the disconnection of the coil of the latch solenoid valve at an intermediate potential between the HI level and the LOW level, and checks the abnormality of the switch element one by one. Even when the valve is open, it is possible to detect abnormalities related to the valve closing operation without actually closing the valve.After detecting a failure, the gas flow control valve shuts off the gas passage and the gas cooking equipment cannot be used. And ensure safety.

According to a tenth aspect of the present invention, when the fire is extinguished, the main control circuit closes the latch solenoid valve, sets the gas flow control valve to the minimum flow position, and performs combustion detection by the combustion detection circuit. A control circuit for a latch solenoid valve of a gas cooking appliance according to any one of claims 1 to 9, wherein the state of the latch solenoid valve is confirmed.

In the present invention, when the gas cooking appliance is extinguished, when the latch solenoid valve is closed, the gas flow control valve is set to the minimum flow position, and combustion is detected by the combustion detection circuit,
After determining that the latch solenoid valve has failed to open, and after detecting the failure, the gas flow control valve shuts off the gas passage and disables the use of the gas cooking appliance to ensure safety.

According to an eleventh aspect of the present invention, at the time of ignition, the main control circuit sets the gas flow control valve to the ignition position and then ignites, and the combustion detection circuit detects the combustion, thereby detecting the latch solenoid valve. Claim 1 wherein the status is confirmed.
A control circuit for a latch solenoid valve of a gas cooking appliance according to any one of claims 10 to 10.

In the present invention, when the gas cooking appliance is ignited, the latch solenoid valve is closed, the gas flow control valve is set to the ignition position, the igniter is operated, and then combustion is detected by the combustion detection circuit. Then, it is determined that the latch solenoid valve has failed to open. After the failure is detected, the gas passage is shut off by the gas flow regulating valve, and then the use of the gas cooking appliance is disabled to ensure safety.

According to a twelfth aspect of the present invention, there is provided a nonvolatile failure detection storage memory, wherein the main control circuit stores information on the detected failure in the failure detection storage memory. 11 is a control circuit of the gas cooking appliance according to any one of the first to eleventh aspects.

In the present invention, the failure detection that has occurred in the gas cooking appliance is stored in the failure detection storage memory, so that the failure detection is not lost even when the battery is removed or in the event of a power failure. Disable use and ensure safety.

Hereinafter, embodiments of the present invention will be described.

[0060]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a control circuit for a latch solenoid valve of a gas cooking appliance according to the present invention will be described below with reference to the drawings.

FIG. 1 is a circuit diagram showing the configuration of this embodiment. The same components as those of the conventional example shown in FIG. In FIG. 1, a latch solenoid valve 11
Is provided with one coil 12, and the opening or closing of the latch solenoid valve 11 is performed according to the direction of current flow. In FIG.
The current direction 12a indicates the current direction when the valve is closed, and the current direction 12b indicates the current direction when the valve is opened. If the valve is opened or closed, the position is maintained by magnetic force or spring force even when the voltage application to the coil 12 is stopped.

FIG. 2 is a block diagram showing the configuration of the gas system in this embodiment. In FIG. 2, the gas passage 8 first passes through the latch solenoid valve 11 from the main valve of the gas.
The latch solenoid valve 11 serves as a main valve of the gas cooking appliance. Next, the gas passes through the gas flow control valve 9. The gas flow control valve 9 adjusts the flow rate of the gas and the strength of the thermal power.

FIG. 3 is a block diagram showing the configuration of the control system in this embodiment. The same components as those in FIG. 4 are denoted by the same reference numerals. In FIG. 3, reference numeral 13 denotes a combustion detection circuit for detecting combustion based on the combustion flame detected by the thermocouple 14, reference numeral 15 denotes a latch solenoid valve driving circuit, reference numeral 16 denotes a gas flow control valve driving circuit for controlling the gas flow control valve 9, 1
Reference numeral 7 denotes a failure detection storage memory that stores the detected failure. These are controlled by the microcomputer 4. Reference numeral 18 denotes a sub power source, which is a power source when the latch solenoid valve driving circuit 15 performs a valve closing operation.

The operation and operation of the above configuration will be described. First, a basic operation when the power is turned on, that is, an operation in a use preparation stage will be described. In FIG. 1, when a power switch (not shown) of the gas cooking appliance is turned on,
A low level is output from each of the ports 4a and 4b, and the valve opening driver 19a and the valve opening driver 19b are surely turned off so as not to open the valve. Thereafter, an 80 Hz pulse signal is output from the port 4c and the port 4d, and the 80 Hz rectifier circuit 5a and the 80 Hz rectifier circuit 5c respectively.
Valve closing driver 20a and valve closing driver 2
0b is turned off so that no current flows through the coil 12.

Thereafter, the HI level is output from the port 4e, the transistor 18b is turned on via the transistor 18a, and the capacitor 18c is charged. At this time, the microcomputer 4 monitors the charging time to the auxiliary power supply 18 through the port 4f, and if the charging time is not within a certain time range, the use of the gas cooking appliance is disabled. If the charging time is within a certain time range, the pulse signals of 80 Hz at the ports 4c and 4d are stopped. 8
By stopping the 0 Hz pulse signal, the valve-closing driver 20a and the valve-closing driver 20b are each turned on, a voltage is applied to the coil 12 for a certain period of time, a current flows in the current direction 12a, and the The valve 11 is securely closed, and after a certain period of time, a pulse signal of 80 Hz is output again from each of the port 4c and the port 4d.
The valve closing driver 20a and the valve closing driver 20b are turned off via the 0 Hz rectifier circuit 5a and the 80 Hz rectifier circuit 5c, so that no current flows through the coil 12.

Thereafter, during and after combustion of the gas cooking appliance,
Before the combustion, the microcomputer 4 always monitors whether or not a predetermined partial pressure value by the resistors 21 and 22 is input to the ports 4g and 4h, respectively. Valve driver 20a,
Any one of the valve closing driver 20b, the valve opening driver 19a, and the valve opening driver 19b is determined to have failed, or the coil 12 has been disconnected, and the combustion of the gas cooking appliance has been extinguished by the gas flow rate regulating valve 9. Use of cooking appliances is prohibited. Thus, the preparation for using the gas cooking appliance is completed.

Next, the ignition operation will be described. When an ignition switch (not shown) is turned on, the gas flow control valve 9 opens to a gas flow position at the time of ignition, and an ignition operation is started. At this time, if combustion is detected by the combustion detection circuit 13, the microcomputer 4 determines that the latch solenoid valve 11 has failed to open, and disables the use of the gas cooking appliance. If the combustion is not detected, the HI level is output from the port 4a after a certain period of time,
Turn on the valve opening driver 19a, and then,
Output a pulse signal of 80Hz from the rectifier circuit 5b
By turning on the valve-opening driver 19b while the voltage is being applied to the coil 12 for a certain period of time, a current flows in the current direction 12b, the latch solenoid valve 11 is opened, and the gas cooking appliance burns. State.

Next, the fire extinguishing operation will be described. When a fire extinguishing switch (not shown) is turned on, a LOW level is output from each of the ports 4a and 4b, and the valve opening driver 19a and the valve opening driver 19b are surely turned off. After that, a LOW level is output from the port 4e,
By turning off the transistor 18b via the transistor 18a, charging of the sub power supply 18 is stopped. Thereafter, the pulse signals of 80 Hz from the ports 4c and 4d are stopped. By stopping the pulse signal of 80 Hz, the valve closing driver 20a and the valve closing driver 20b are turned on, a voltage is applied to the coil 12 for a certain period of time, a current flows in the current direction 12a, and the latch solenoid valve is turned on. 11
Is closed.

Thereafter, the gas flow control valve 9 is set to the minimum flow position, and is monitored by the combustion detection circuit 13 for a certain period of time. When combustion is detected, the gas flow control valve 9 is closed, and the gas cooking equipment is closed. Is not allowed. If the combustion is not detected, the gas flow control valve 9 is closed, and the use of the gas cooking appliance ends.

Next, ensuring security will be described.
First, a case will be described in which a power failure or a battery is removed during burning of the gas cooking appliance, and all output signals from the microcomputer 4 disappear. At this time, the pulse signals of 80 Hz at the ports 4c and 4d for which the valve-closing driver 20a and the valve-closing driver 20b have been turned off disappear. However, since the electric charges are accumulated in the capacitors 23 and 24, the electric charges are accumulated. , The valve closing driver 20a and the valve closing driver 20b are not immediately turned on.

While the electric charge is gradually discharged, the valve-opening driver 19a and the valve-opening driver 19b are surely turned off by the comparators 25 and 26, respectively. When the driver 20b is turned on, it is ensured that the current direction 12a flows through the coil 12. In this case, the power of the comparator 25 and the comparator 26 is
Use the charge of When the valve-closing driver 20a and the valve-closing driver 20b are turned on, the charge of the auxiliary power supply 18 is applied to the coil 12, the latch solenoid valve 11 is closed, and the combustion of the gas cooking appliance is extinguished.

The valve closing operation during valve opening can be confirmed by turning on the valve closing driver 20a.
Although a current flows from 0a to the resistor 22 via the coil 12, the latch solenoid valve 11 does not operate because all the resistors 22 have high impedance. At this time, the microcomputer 4 monitors that the voltage level of the sub power supply 18 is input to the ports 4g and 4h, and when the voltage is divided by the resistors 21 and 22, the valve closing driver is used. It is determined that an open failure has occurred in 20a.

When the valve closing driver 20b is similarly turned on after the valve closing driver 20a is turned off, the microcomputer 4 confirms that the voltage level of the auxiliary power supply 18 is input to the ports 4g and 4h. When the partial pressure value is determined by the resistors 21 and 22, it is determined that the valve closing driver 20b has an open failure. When a failure is detected, the gas flow control valve 9 is closed, the combustion of the gas cooking appliance is extinguished, and then the use of the gas cooking appliance is disabled.

The above failure detection is stored in the failure detection storage memory 17 which is stored even without power supply, so that when a battery is removed, the failure detection is not lost even in the event of a power failure. Disable the use of cooking appliances again.

[0075]

According to the first aspect of the present invention, there is provided a latch solenoid valve driving circuit for driving a latch solenoid valve for opening and closing a gas passage, and is provided in series downstream of the latch solenoid valve to adjust a gas flow rate. A gas flow regulating valve driving circuit for driving a gas flow regulating valve to be operated, a combustion detecting circuit for detecting combustion, a main control circuit for controlling the overall operation, and a main power supply for supplying power to the main control circuit. The auxiliary power supply, the latch solenoid valve drive circuit, by using a control circuit of the latch solenoid valve of the gas cooking appliance is configured to perform a valve closing operation by the auxiliary power supply, at the time of power failure of the main power supply, Even when the battery voltage decreases, the latch solenoid valve can be reliably closed.

According to a second aspect of the present invention, a main control circuit detects a failure by using a control circuit for a latch solenoid valve of a gas cooking appliance according to the first aspect, wherein the control circuit detects a failure of a sub power supply. In this case, after the gas passage is shut off by the gas flow control valve, use of the gas cooking appliance is disabled, and safety can be ensured.

According to a third aspect of the present invention, the main control circuit closes by turning off a control signal to the latch solenoid valve drive circuit relating to the energization of the switch element for applying a closing voltage to the latch solenoid valve. 3. The gas according to claim 1, wherein a valve operation is instructed, and the latch solenoid valve driving circuit turns on the switch element to perform a valve closing operation when the control signal from the main control circuit is turned off. By using the control circuit for the latch solenoid valve of the cooking appliance, the valve closing operation can be reliably executed even if there is an abnormality in the main control circuit.

According to a fourth aspect of the present invention, the main control circuit turns off a control signal to a latch solenoid valve drive circuit related to energization of a switch element for applying a voltage in an opening direction to the latch solenoid valve. Instruct the valve closing operation after turning off the switch element, and the latch solenoid valve drive circuit turns off the switch element itself prior to the valve closing operation when instructed by the main control circuit to perform the valve closing operation. With the control circuit for the latch solenoid valve of the gas cooking appliance according to the third aspect, the valve opening operation and the valve closing operation do not work instantaneously at the same time, so that the valve closing operation can be reliably performed. In addition, the valve can be reliably closed even in the event of a power failure or voltage drop in the main power supply, or an abnormality in the main control circuit.

According to a fifth aspect of the present invention, the main control circuit detects disconnection of the coil of the latch solenoid valve before and during the operation of the gas cooking appliance. After the disconnection is detected, the gas flow control valve shuts off the gas passage by using the control circuit of the latch solenoid valve of the gas cooking appliance, and the use of the gas cooking appliance is disabled to ensure safety. Can be.

According to a sixth aspect of the present invention, in the fifth aspect, the main control circuit detects the disconnection failure of the coil of the latch solenoid valve based on the potential between the HI level and the LOW level of the main power supply. By providing a control circuit for the latch solenoid valve of the gas cooking appliance concerned, a reasonable detection means can be provided when the main control circuit is constituted by a microcomputer.

According to a seventh aspect of the present invention, the main control circuit detects a failure of a switch element for applying a voltage to the coil of the latch solenoid valve.
If a failure is detected by using the control circuit of the latch solenoid valve of the gas cooking appliance according to any of the above, after the gas passage is shut off by the gas flow regulating valve, the use of the gas cooking appliance is disabled and safety is reduced. Can be secured.

According to an eighth aspect of the present invention, the main control circuit detects a failure of the switch element for applying a voltage to the coil of the latch solenoid valve based on the potential between the HI level and the LOW level of the main power supply. By providing the control circuit for the latch solenoid valve of the gas cooking appliance according to claim 7, a reasonable detection means can be provided when the main control circuit is constituted by a microcomputer.

According to a ninth aspect of the present invention, the main control circuit detects a failure in the valve closing operation of the latch solenoid valve drive circuit without shutting off the gas passage even when the latch solenoid valve is open. By providing the control circuit for the latch solenoid valve of the gas cooking appliance according to any one of claims 1 to 8, the valve can be closed without actually closing even when the latch solenoid valve is open. An abnormality related to the operation can be detected. After the failure is detected, the gas passage is shut off by the gas flow regulating valve, and then the use of the gas cooking appliance is disabled, and safety can be ensured.

According to a tenth aspect of the present invention, when the fire is extinguished, the main control circuit closes the latch solenoid valve, sets the gas flow control valve to the minimum flow position, and performs combustion detection by the combustion detection circuit. Thus, the state of the latch solenoid valve is confirmed by the control circuit of the latch solenoid valve of the gas cooking appliance according to any one of claims 1 to 9, and after the failure is detected, the gas flow regulating valve is used. After shutting off the gas passage, use of the gas cooking appliance is disabled, and safety can be ensured.

According to an eleventh aspect of the present invention, in the ignition, the main control circuit sets the gas flow rate control valve to the ignition position and then ignites, and the combustion detection circuit detects the combustion, thereby detecting the latch solenoid valve. Claim 1 wherein the status is confirmed.
According to the control circuit of the latch electromagnetic valve of the gas cooking appliance according to any one of claims 10 to 14, after the failure is detected, the gas passage is shut off by the gas flow regulating valve, and then the use of the gas cooking appliance is disabled. Nature can be secured.

According to a twelfth aspect of the present invention, there is provided a nonvolatile failure detection storage memory, wherein the main control circuit stores information on the detected failure in the failure detection storage memory. By using the control circuit of the gas cooking appliance according to any one of the above, the memory of the failure detection is not lost even when the battery is removed or at the time of a power failure, making it impossible to use the gas cooking appliance again, and improving safety. Can be secured.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a configuration of an embodiment of a control circuit for a latch solenoid valve of a gas cooking appliance according to the present invention.

FIG. 2 is a block diagram showing a configuration of a gas system in the embodiment.

FIG. 3 is a block diagram showing a configuration of a control system in the embodiment.

FIG. 4 is a circuit diagram showing a configuration of a control circuit of a conventional gas cooking appliance.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solenoid valve 1a Suction coil 1b Holding coil 2a, 2b Suction driver 3a, 3b Transistor 4 Microcomputer (main control circuit) 4a-4h Port 5, 5a-5c 80Hz rectifier circuit 6 Holding driver 7 Main power supply 8 Gas passage 9 Gas flow control valve 10 Burner 11 Latch solenoid valve 12 Coil 12a, 12b Current direction 13 Combustion detection circuit 14 Thermocouple 15 Latch solenoid valve drive circuit 16 Gas flow control valve drive circuit 17 Failure detection storage memory 18 Sub power supply 18a, 18b Transistor 18c Capacitors 19a, 19b Valve opening driver (switch element) 20a, 20b Valve closing driver (switch element) 21, 22 Resistance 23, 24 Capacitor 25, 26 Comparator

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Mitsuo Yokohata 1006 Kazuma Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. F-term (reference) 3K003 XA03 XB06 XB07 XB08

Claims (12)

[Claims] 1. A latch solenoid valve driving circuit for driving a latch solenoid valve for opening and closing a gas passage, and a gas installed in series downstream of the latch solenoid valve for driving a gas flow regulating valve for adjusting a gas flow rate. A flow control valve drive circuit, a combustion detection circuit for detecting combustion, a main control circuit for controlling the entire operation, and a sub-power supply different from a main power supply for supplying power to the main control circuit; The solenoid valve drive circuit is a control circuit for a latch solenoid valve of a gas cooking appliance configured to perform a valve closing operation by the auxiliary power supply. 2. The control circuit according to claim 1, wherein the main control circuit detects a failure of the auxiliary power supply. 3. A main control circuit instructs a valve closing operation by turning off a control signal to a latch solenoid valve driving circuit related to energization of a switch element for applying a voltage in a closing direction to the latch solenoid valve, and The latch solenoid valve of a gas cooking appliance according to any one of claims 1 to 2, wherein the solenoid valve drive circuit turns on the switch element to perform a valve closing operation when the control signal from the main control circuit is turned off. Control circuit. 4. The main control circuit turns off the switch element by turning off a control signal to a latch solenoid valve drive circuit relating to energization of the switch element for applying a voltage in the opening direction to the latch solenoid valve. 4. The valve closing operation is instructed, and the latch solenoid valve drive circuit turns off the switch element itself prior to the valve closing operation when instructed by the main control circuit to perform the valve closing operation. Control circuit for latching solenoid valve of gas cooking equipment. 5. The gas cooking apparatus according to claim 1, wherein the main control circuit detects disconnection of the coil of the latch solenoid valve before and during operation of the gas cooking appliance. Control circuit for the latch solenoid valve of the equipment. 6. A main control circuit comprising: a HI level of a main power supply;
6. The control circuit for a latch solenoid valve of a gas cooking appliance according to claim 5, wherein a disconnection failure of a coil of the latch solenoid valve is detected based on a potential between the OW level and the OW level. 7. The latching solenoid valve of a gas cooking appliance according to claim 1, wherein the main control circuit detects a failure of a switch element for applying a voltage to a coil of the latching solenoid valve. Control circuit. 8. A main control circuit comprising: a HI level of a main power supply;
8. The control circuit for a latch solenoid valve of a gas cooking appliance according to claim 7, wherein a failure of a switch element for applying a voltage to a coil of the latch solenoid valve is detected based on a potential during the OW level. 9. The control circuit according to claim 1, wherein the main control circuit detects a failure in the closing operation of the latch solenoid valve drive circuit without shutting off the gas passage even when the latch solenoid valve is open.
9. A control circuit for a latch solenoid valve of a gas cooking appliance according to claim 8. 10. The main control circuit closes the latch solenoid valve at the time of fire extinguishing, sets the gas flow regulating valve to the minimum flow position, and performs combustion detection by the combustion detection circuit, thereby detecting the state of the latch solenoid valve. The control circuit for a latch solenoid valve of a gas cooking appliance according to any one of claims 1 to 9, wherein the control circuit confirms the following. 11. The main control circuit checks the state of the latch solenoid valve by setting the gas flow control valve to the ignition position, igniting the ignition, and performing combustion detection by the combustion detection circuit. A control circuit for a latch solenoid valve of a gas cooking appliance according to any one of claims 1 to 10. 12. The device according to claim 5, further comprising a nonvolatile failure detection storage memory, wherein the main control circuit stores information on the detected failure in the failure detection storage memory. Control circuit for gas cooking equipment.