JP2000283467A - Hot water heater for cooking stove - Google Patents

Abstract

PROBLEM TO BE SOLVED: To end water heating operation automatically by shutting off or throttling a control valve based on the temperature gradient of characteristic curve and/or boiling sound thereby deciding completion of water heating accurately even when boiling sound is generated. SOLUTION: When a water heating key is selected, a CPU 7 observes the output from a temperature sensor 5 corresponding to a temperature detecting means and operates a temperature gradient. It is calculated by predetermining a temperature and measuring the time when each temperature is reached. When the temperature gradient reaches a predetermined value or below, the CPU 7 shuts off a gas solenoid valve 9 to extinguish fire automatically. When boiling sound generated from a kettle 3, or the like, by steam pressure is detected, the CPU 7 decides whether the temperature gradient has reaches a predetermined value or below or not and whether the bottom temperature of the kettle 3, or the like, has reached a specified level or not. When these conditions are satisfied, the CPU 7 shuts off a gas solenoid valve 9 immediately to extinguish fire automatically.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stove water heater, and more particularly to a stove water heater capable of judging the completion of water heating accurately even when a boiling sound is heard and automatically terminating the water heater.

[0002]

2. Description of the Related Art Conventionally, a gas stove as shown in FIG. 3 has been known. At the center of the burner 1 of the gas stove 10, a temperature sensor 5 for detecting the temperature of the kettle 3 and the bottom of the pan is provided. When a “water heater” key (not shown) of the gas stove 10 is selected, the CPU 7 detects the temperature of the temperature sensor 5 as time passes. Then, a temperature gradient with respect to time is calculated, and the amount of water put into the kettle 3 or the like is determined from the temperature gradient.

The reason for determining the amount of water is that the temperature gradient varies depending on the amount of water. Based on the determined amount of water, if the temperature gradient is small for a certain period of time (the time depends on the amount of water), boiling is determined, and the fire is automatically extinguished after a certain period of time.

[0004] For example, as shown in FIG.
The time at which the temperature reaches Ta from Tb is defined as t. If the time exceeds t / 2 until the temperature rises by about 1 ° C. after reaching Tb, it is determined that boiling occurs, and the CPU 7 shuts off the gas solenoid valve 9 to automatically extinguish the fire. .

[0005]

By the way, in the conventional gas stove 10, there is a case in which the boiling sound continues to be emitted for a maximum of about one minute before the CPU 7 automatically extinguishes the fire depending on the material, shape, and amount of water of the kettle 3. . Also, the boiling noise is loud and often extinguishes the gas manually. In this case, the effect of the "water heater" function was not obtained.

The present invention has been made in view of such conventional problems, and provides a stove water heater capable of accurately determining completion of water heating even when a boiling sound is heard and automatically stopping water heating. The purpose is to do.

[0007]

SUMMARY OF THE INVENTION Therefore, the present invention (claim 1) provides a burner, a control valve for adjusting a supply amount of gas sent to the burner, and / or opening and closing the supply of gas, and the burner. An object to be heated containing water to be heated, sound detection means for detecting a boiling sound due to vapor pressure from the object to be heated, temperature detection means for detecting the temperature of the object to be heated, Characteristic curve slope calculating means for calculating the slope of the characteristic curve with respect to time of the temperature detected by the temperature detecting means,
Temperature gradient determining means for determining whether or not the slope of the characteristic curve calculated by the characteristic curve slope calculating means has become equal to or less than a predetermined temperature gradient, and the boiling sound detected by the sound detecting means is predetermined. Sound determining means for determining whether or not a predetermined loudness is exceeded, and wherein the slope of the characteristic curve is less than or equal to the predetermined temperature gradient by the temperature gradient determining means and / or the boiling sound is determined by the sound determining means. Means for shutting off the control valve or reducing the opening of the control valve when it is determined that the magnitude of the control valve has been exceeded.

[0008] The control valve controls the supply of gas to be sent to the burner and / or opens and closes the supply of gas. The object to be heated containing water is heated by the burner. The object to be heated is, for example, a kettle that emits a boiling sound due to the vapor pressure when water is boiled. The sound detecting means detects the boiling sound.

The temperature detecting means detects the temperature of the object to be heated. The characteristic curve slope calculating means calculates the slope of the characteristic curve with respect to the time of the temperature detected by the temperature detecting means. The temperature gradient determining means determines whether the gradient calculated by the characteristic curve gradient calculating means has fallen below a predetermined temperature gradient. As the temperature gradient becomes smaller, it approaches boiling. The situation approaching the boiling is determined by determining a predetermined temperature gradient in advance and comparing with this value.

On the other hand, the sound judging means judges whether or not the boiling sound detected by the sound detecting means has exceeded a predetermined loudness. In the control valve shutoff means, the control valve is shut off or controlled when the slope of the characteristic curve is determined by the temperature gradient determination means to be equal to or lower than the predetermined temperature gradient and / or the boiling sound exceeds the predetermined loudness by the sound determination means. Reduce the opening of the valve.

The control valve shutoff means shuts off the control valve according to the judgment of the temperature gradient judging means when the boiling sound is not detected. Further, when it is determined that the boiling sound exceeds a predetermined volume by the sound determination means, it is preferable to perform a shutoff of the control valve and the like in consideration of the determination conditions of the temperature gradient determination means in order to be careful. .

As described above, automatic fire extinguishing can be performed promptly regardless of whether or not boiling sound is generated. In addition, the automatic fire extinguishing at this time is performed based on both the conditions of the temperature gradient and the boiling sound, which leads to prevention of malfunction.

[0013] Further, according to the present invention (claim 2), the control valve shut-off means and the like are arranged such that the temperature detected by the temperature detecting means is equal to or higher than a predetermined temperature, and the characteristic is determined by the temperature gradient judging means. When the slope of the curve is equal to or less than the predetermined temperature gradient and / or when the sound determination unit determines that the boiling sound exceeds the predetermined volume, the control valve is shut off or the opening of the control valve is reduced. It is characterized by.

In addition to the conditions of the temperature gradient and the boiling sound, the height of the temperature detected by the temperature detecting means is also added to the determination condition. Then, based on these three conditions, the control valve is shut off or the opening of the control valve is reduced. The reason for taking into account the high temperature is to increase the accuracy of boiling detection. This is also to prevent the malfunction of the automatic fire extinguishing with further caution.

Further, according to the present invention (claim 3), the control valve shut-off means may include a step of: determining that the temperature detected by the temperature detecting means is equal to or higher than a predetermined temperature, and the temperature gradient judging means judges the slope of the characteristic curve. When the temperature is equal to or less than the predetermined temperature gradient and the sound determination means determines that the boiling sound exceeds the predetermined loudness, the control valve is immediately shut off or the opening of the control valve is reduced. .

When the boiling sound exceeds a predetermined level, the control valve is immediately shut off or the opening degree of the control valve is reduced on condition that the temperature is higher than a predetermined temperature and lower than a predetermined temperature gradient. In this way, immediately processing can prevent the boiling sound from continuing for a long time.

Furthermore, the present invention (claim 4) provides a burner,
A control valve for adjusting the supply amount of gas to be sent to the burner and / or opening and closing the gas supply; an object to be heated containing water to be heated by the burner; and a vapor pressure from the object to be heated. Sound detecting means for detecting a boiling sound caused by the sound, sound judging means for judging whether or not the boiling sound detected by the sound detecting means exceeds a predetermined loudness; Is configured to shut off the control valve or to reduce the opening of the control valve when it is determined that the control valve exceeds the predetermined size.

The boiling sound is judged by the sound judging means, and when it is judged that the boiling sound exceeds a predetermined volume, the control valve is shut off or the opening degree of the control valve is reduced by means of a control valve shutoff or the like. As described above, even if water is heated with a burner to which the temperature detecting means is not attached, the fire can be automatically extinguished if a boiling sound is generated.

[0019]

Embodiments of the present invention will be described below. FIG. 1 shows a configuration diagram of an embodiment of the present invention. The same components as those in FIG. In FIG. 1, a sound sensor 11 corresponding to sound detection means is attached to a side portion of the gas stove 10 in order to detect a boiling sound due to a vapor pressure from the kettle 3 or the like. However, the sound sensor 11 may be attached to a wall or the like around the gas stove 10. The sound detected by the sound sensor 11 is C
The data is input to the PU 7.

Next, the operation of the embodiment of the present invention will be described. When the "water heater" key is selected, the CPU 7 observes the output from the temperature sensor 5 corresponding to the temperature detecting means. Then, as shown in FIG. 2, the temperature gradient [(T2-T
1) / (t2−t1)]. This temperature gradient is
For example, the temperatures T1 and T2 are determined in advance, and the time required to reach each temperature is measured and calculated.

The CPU 7 calculates the temperature gradient [(T2-T1) /
(T2−t1)] is determined to be equal to or lower than a predetermined temperature gradient, and whether the bottom temperature of the kettle 3 or the like has reached, for example, T2. Then, when both conditions are reached, the CPU 7 shuts off the gas solenoid valve 9 and extinguishes the fire automatically after t3 seconds from that point. However, the gas solenoid valve 9
May be adjusted so as to narrow the opening.

As described above, when the kettle 3 does not emit a boiling sound, the fire can be automatically extinguished immediately (after t3 seconds) based on the temperature gradient.

On the other hand, when the CPU 7 detects the boiling sound due to the vapor pressure from the kettle 3 or the like, the CPU 7 determines that the temperature gradient [(T2−T1) / (t2−t1)] is a predetermined temperature. It is determined whether the gradient has become equal to or less than the gradient and whether the bottom temperature of the kettle 3 or the like has reached, for example, T2. And
When these conditions are reached, the CPU 7 immediately shuts off the gas solenoid valve 9 to automatically extinguish the fire. However, the opening degree of the gas solenoid valve 9 may be adjusted so as to be reduced.

As described above, the fire can be automatically extinguished immediately when the boiling sound is generated, regardless of the material, the shape, and the amount of water of the kettle 3 or the like. This eliminates the need to manually extinguish the gas when a boiling sound is generated. The reason why a condition such as a temperature gradient is set in addition to the sound pressure is to prevent a malfunction caused by only the sound pressure as much as possible.

In the case of the gas stove 10 to which the temperature sensor 5 is not attached, when a boiling sound is detected from the kettle 3 or the like, the fire may be automatically extinguished or the opening of the gas solenoid valve 9 may be reduced. .

[0026]

As described above, according to the present invention, since the control valve is shut off or the opening of the control valve is reduced based on the temperature gradient and / or the boiling sound of the characteristic curve, the boiling sound is generated. Automatic fire extinguishing can be performed promptly in both cases. In addition, the automatic fire extinguishing at this time is performed based on both the conditions of the temperature gradient and the boiling sound, which leads to prevention of malfunction.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a diagram illustrating a method of calculating a temperature gradient.

FIG. 3 is a configuration diagram of a conventional gas stove.

FIG. 4 is a diagram illustrating a conventional method for automatically extinguishing a gas stove.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Burner 3 Kettle 5 Temperature sensor 7 CPU 9 Gas solenoid valve 10 Gas stove 11 Sound sensor

Claims (4)

[Claims] 1. A burner, a control valve for adjusting a supply amount of gas sent to the burner and / or opening and closing the supply of gas, an object to be heated filled with water heated by the burner, Sound detection means for detecting a boiling sound due to the vapor pressure from the object to be heated, temperature detection means for detecting the temperature of the object to be heated, and a slope of a characteristic curve of the temperature detected by the temperature detection means with respect to time. A characteristic curve slope calculating means for calculating the characteristic curve slope; a temperature gradient determining means for determining whether a slope of the characteristic curve calculated by the characteristic curve slope calculating means is equal to or less than a predetermined temperature gradient; A sound determining means for determining whether or not the boiling sound detected by the means has exceeded a predetermined level; and a gradient of the characteristic curve being lower than or equal to the predetermined temperature gradient by the temperature gradient determining means and / or The sound judgment means A stove water heater, comprising: means for shutting off the control valve or reducing the opening of the control valve when it is determined that the boiling sound exceeds the predetermined volume. 2. The control valve shutoff means according to claim 1, wherein said temperature detected by said temperature detecting means is equal to or higher than a predetermined temperature, and said temperature gradient judging means sets said characteristic curve to have said predetermined temperature gradient. 2. The control valve according to claim 1, wherein the control valve is shut off or the opening of the control valve is reduced when it is determined that the boiling noise exceeds the predetermined volume by the sound determination unit. Stove water heater. 3. The control valve shutoff means and the like, wherein the temperature detected by the temperature detection means is equal to or higher than a predetermined temperature, and the slope of the characteristic curve is equal to or less than the predetermined temperature gradient by the temperature gradient determination means. 2. The stove water heater according to claim 1, wherein when the sound judging means judges that the boiling sound exceeds the predetermined volume, the control valve is immediately shut off or the opening of the control valve is reduced. . 4. A burner, a control valve for adjusting a supply amount of gas sent to the burner and / or opening / closing the supply of gas, an object to be heated filled with water heated by the burner, Sound detection means for detecting a boiling sound due to the vapor pressure from the object to be heated, and sound determination means for determining whether the boiling sound detected by the sound detection means has exceeded a predetermined loudness, When the sound determination means determines that the boiling sound exceeds the predetermined volume, the control means shuts off the control valve or narrows the opening of the control valve. Stove water heater.