JPH11108362A - Safety device for cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve temperature detection accuracy and responsiveness and prevent a cooking pan from being influenced by a material quality in a safety device having an overheating prevention function utilizing a temperature sensitive metal. SOLUTION: A temperature sensitive part 3, which receives heat from as cooking pan 1, and has a Curie point where permeability and saturated magnetic flux density are lowered when predetermined temperature is reached, is brought into direct contact with a pan bottom of the cooking pan 1. Yokes 15a, 15b separated from and facing to the temperature sensitive part 3 include two abutment surfaces separated from and facing to the temperature sensitive part 3 with one abutment surface magnetized to an N pole and the other abutment surface magnetized to an S pole. Both abutment surfaces attracted to the temperature sensitive part 3 to form a closed magnetic path, and when the cooking pan reaches abnormal overheating temperature, the temperature sensitive part 3 and the yokes 15a, 15b are separated from each other, whereby a valve disk provided on a gas flow passage to a burner is closed to interrupt combustion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooker such as a table stove or a gas cooker, and more particularly to monitoring whether or not a pot bottom temperature has reached a predetermined temperature. Close the safety device of the cooker.

[0002]

2. Description of the Related Art Conventionally, in order to prevent a tempura fire, burning, etc., the temperature of the pot bottom of a stove serving as a cooking appliance is detected by a thermistor, and when the detected temperature is higher than a predetermined temperature, cooking is stopped. Instrument safety devices are known. For example, the stove shown in FIG. 5 is provided with a thermistor 40 for detecting the temperature of the burner head 5, and this thermistor 4
Based on 0, the pot bottom temperature of the cooking pot 1 is detected, and the controller 43 determines whether the detected temperature is equal to or higher than the set upper limit temperature, and based on the determination result, controls the opening and closing of the gas passage. However, the conventional stove safety device requires a detection circuit for detecting the pan bottom temperature, a determination circuit for judging the pan bottom temperature, and the like, thus increasing the cost of the entire stove. Therefore,
As shown in Japanese Patent Application No. 8-315405 filed earlier, a sensor unit that receives heat from the bottom of a pot of a rice cooker as a cooker is provided,
A cooker provided with a non-magnetic cap in the sensor part in contact with the bottom of the pot, and a temperature-sensitive ferrite in the center of the back of the cap, whose magnetic permeability and saturation magnetic flux density decrease when the temperature approaches the Curie temperature. Has proposed a safety device.
A suction portion that faces the temperature-sensitive ferrite and is attracted and held by the magnetic force of a permanent magnet; a connecting rod that moves up and down integrally with the suction portion; and a valve body that opens and closes a gas flow path in the middle of the connecting rod. Is provided, and heat is conducted from the bottom of the pot to the temperature-sensitive ferrite via the cap, and the valve body is closed when the adsorption section is released from the temperature-sensitive ferrite.

[0003]

However, unlike a rice cooker, if a stove used in a rice cooker is used as it is, there is a problem that the detected temperature varies. For example, in the case of a rice cooker, a predetermined pot is used, and the material (thermal conductivity and magnetic permeability) of the pot and the contact state between the pot and the sensor unit are constant. Since it is surrounded by the casing, its ambient temperature is also constant. In contrast, on the stove,
Pots of various materials such as iron, aluminum, and copper are used, and the contact state between the pot and the sensor unit and the ambient temperature are not constant. In addition, while the operating temperature of the rice cooker is set to about 140 ° C, it is necessary to set the operating temperature to 250 ° C on the stove in order to prevent the tempura from burning or burning. There is a problem that the change in the saturation magnetic flux density around this temperature becomes small, and the detected temperature varies. Furthermore, in the rice cooker, as described above, a cap is provided between the bottom of the pot and the temperature-sensitive ferrite to protect the temperature-sensitive ferrite. In addition, there has been a problem that the temperature difference between the pot bottom and the temperature-sensitive ferrite becomes large, and the temperature detection accuracy and the response are inferior. Also, if the contact area between the temperature-sensitive ferrite and the yoke is set large to obtain a stable adsorption force, the heat capacity of the temperature-sensitive part and the adsorption part increases, and the response as a temperature sensor becomes worse. There was a problem. Alternatively, if the magnetic force of the magnet is set to a large value, the magnetic flux lines extend far, and are easily affected by the material of the cooking pot. Alternatively, there is a problem that the detected temperature is different from the case where an aluminum pan is used. In this case, when the thickness of the cap is increased so as not to be affected by the material of the cooking pan, the heat capacity of the temperature-sensitive ferrite increases, and the responsiveness similarly deteriorates. Then, the safety device of the cooking device of the present invention solves the above-mentioned problems, and aims at improving the temperature detection accuracy and the responsiveness of the safety device having the overheating prevention function.

[0004]

According to a first aspect of the present invention, there is provided a safety device for a cooking device, comprising: a cap for receiving heat by contacting the bottom of a cooking pot; A temperature-sensitive part made of a temperature-sensitive material having a Curie point at which the magnetic permeability and the saturation magnetic flux density decrease when the temperature is reached; an adsorption part facing and separating from the temperature-sensitive part using a permanent magnet; and a gas to a burner. In a safety device for a cooker provided with a valve element for opening and closing the flow path and valve closing means for closing the valve element when the suction part is detached from the temperature sensing part, the cap abutting on the cooking pot, The gist is that it is formed of a temperature-sensitive metal and also serves as the temperature-sensitive part.

According to a second aspect of the present invention, there is provided a safety device for a cooking device, comprising: a cap for receiving heat by contacting the bottom of the cooking pot; and a magnetic permeability when a predetermined temperature is reached by heat conduction from the cap. And a temperature-sensitive part made of a temperature-sensitive material having a Curie point at which the saturation magnetic flux density decreases, an adsorption part facing and separating from the temperature-sensitive part using a permanent magnet, and a valve for opening and closing a gas flow path to a burner. In a safety device for a cooker comprising a body and valve closing means for closing the valve body when the suction unit is separated from the temperature sensing unit, the suction unit contacts the temperature sensing unit and closes the magnetic path. In this case, two points of contact surfaces that come into contact with and separate from the temperature-sensitive portion are provided so that one contact surface is magnetized to the N pole and the other contact surface is magnetized to the S pole.

[0006] A safety device for a cooker according to a third aspect of the present invention is the safety device for a cooker according to the second aspect,
The gist of the invention is that the cap is formed of a temperature-sensitive metal and also serves as the temperature-sensitive part.

[0007] A safety device for a cooker according to a fourth aspect of the present invention is the safety device for a cooker according to the third aspect,
The gist is that the attracting portion is formed by a U-shaped magnet.

[0008] In the safety device for a cooking device according to the first aspect of the present invention having the above-described structure, when the temperature sensing portion directly contacts the bottom of the cooking pot and receives heat from the cooking pot and reaches a predetermined temperature near the Curie temperature. Then, the magnetic permeability and the saturation magnetic flux density of the temperature sensing portion decrease, and the adsorption portion is separated from the temperature sensing portion, and the valve closing means closes the valve provided in the gas flow path to the burner to stop the combustion. Since the temperature sensing part is in direct contact with the pot bottom of the cooking pot, the temperature difference between the cooking pot and the temperature sensing part is reduced, and the pot bottom temperature can be detected accurately and quickly. Therefore, the temperature detection accuracy and the responsiveness in the safety device of the cooking appliance are improved.

The safety device for a cooker according to the second aspect of the present invention having the structure, has two contact surfaces of the suction portion which comes in contact with and separates from the temperature sensing portion, and one of the contact surfaces is the N pole. Then, the other contact surface is magnetized to the S pole and contacts the temperature sensing part to close the magnetic circuit.
Therefore, when in contact, the magnetic circuit closes and the magnetic flux lines concentrate on the contact surface, and a large attraction force is obtained. Furthermore, the magnetic flux lines become a closed magnetic path, and the spread of the magnetic flux lines is reduced, so that the influence of the material of the cooking pot is small. Even if the contact surface between the temperature sensing part and the adsorption part does not reach the Curie temperature, when a part of the temperature sensing part forming the magnetic path reaches the Curie temperature, the magnetic permeability and the saturation magnetic flux density are reduced. The adsorption section is separated from the warm section, and the combustion is stopped. As a result, the accuracy of temperature detection and the response in the safety device of the cooking appliance are improved.

[0010] The safety device for a cooker according to claim 3 of the present invention is the safety device for a cooker according to claim 2,
The temperature sensing part and the cap are formed of a temperature sensing metal, and the suction part contacts the temperature sensing part to close the magnetic circuit. Then, when the heat is directly received from the cooking pot and reaches a predetermined temperature near the Curie temperature, the magnetic permeability and the saturation magnetic flux density of the temperature-sensitive portion decrease, and the suction portion is separated from the temperature-sensitive portion, and the valve closing means is connected to the burner. The valve provided in the gas flow path is closed to stop the combustion. Therefore, since the temperature sensing portion directly contacts the bottom of the cooking pot, the temperature difference between the cooking pot and the temperature sensing portion is reduced, and the temperature of the bottom of the cooking pot can be detected accurately and quickly. Also, when in contact, the magnetic circuit closes and the magnetic flux lines concentrate on the contact surface,
A large suction force can be obtained. Furthermore, the magnetic flux lines become a closed magnetic path, and the spread of the magnetic flux lines is reduced, so that the influence of the material of the cooking pot is small. Even if the contact surface between the temperature sensing part and the adsorption part does not reach the Curie temperature, when a part of the temperature sensing part forming the magnetic path reaches the Curie temperature, the magnetic permeability and the saturation magnetic flux density are reduced. The adsorption section is separated from the warm section, and the combustion is stopped. Therefore,
The temperature detection accuracy and responsiveness in the safety device of the cooking appliance are improved.

The safety device for a cooking appliance according to claim 4 of the present invention is the safety device for a cooking appliance according to claim 3,
The attracting portion is formed by a U-shaped magnet. Therefore, if the suction part is U
Since it is formed integrally with the V-shaped magnet, the safety device of the cooker can be made inexpensive.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION In order to further clarify the structure and operation of the present invention described above, a preferred embodiment of a cooker according to the present invention will be described below. FIG. 1 is a schematic configuration diagram of a stove as one embodiment. The sensor unit 2 for detecting the temperature is provided at the center of the burner head 5 provided on the burner 14. The sensor unit 2 is provided to be urged upward by a pressing spring 7 and abuts against the bottom of the cooking pot 1 placed on the burner 14 to detect the bottom temperature. The burner head 5 is provided with a large number of flame slots at the periphery of the rear surface in a radial manner, and is mounted on the burner 14 to form a main flame slot. Further, the burner head 5 is provided with a thermocouple 9 that generates a thermoelectromotive force by combustion heat, facing the flame port.

On the side of the ignition button 19, a push-push mechanism 21 for alternately determining the advance / retreat position of the ignition button 19 at the time of ignition and at the time of fire extinguishing is provided. Also, ignition button 1
Ignition switch 22 that turns ON / OFF in conjunction with advance / retreat of 9
Is provided near the ignition button 19. Ignition switch 2
2 is turned on at an ignition position by an ignition button 19 to operate an igniter (not shown) to ignite fuel gas,
Stops the igniter with 0FF at the combustion position and fire extinguishing position

The ignition button 19 advances by a pressing operation at the time of ignition (rightward in the figure), and transmits the pressing operation to the casing 33 side with the lever 17 interposed therebetween. The spindle 23 is inserted into the casing 33 so as to be able to advance and retreat.
1 is urged to the left in the figure. On the spindle 23, a main valve 24 for opening and closing the main discharge port 26 of the main body 33 is provided. The main discharge ports 26 are respectively connected to the main nozzles 16 of the combustion section. A magnet-type safety valve 25 is provided at the rear of the casing 33 so as to be coaxial with and facing the spindle 23. The magnetic safety valve 25 is opened and held by the thermoelectromotive force of the thermocouple 9 provided in the burner 14, and when the thermoelectromotive force of the thermocouple 9 falls below a predetermined level, the safety valve 32 is closed to the main discharge port 26. Close the gas flow path.

The sensor section 2 is urged by a pressing spring 7 in a direction in which the sensor section 2 is brought into contact with the bottom surface of the pot, and the temperature-sensitive section 3 whose magnetic permeability and saturation magnetic flux density decrease when the temperature approaches the Curie temperature. An adsorbing section 8 that adsorbs and desorbs in opposition to
A connecting rod 11 that moves up and down integrally with the suction section 8 is provided, and a valve 10 that is fixed to the connecting rod 11 and opens and closes a gas flow path is provided in the middle of the connecting rod 11. The valve 10 is provided with a valve spring 12 that urges in the valve closing direction. The valve spring 12 urges the suction portion 8 provided at one end of the connecting rod 11 in a direction away from the temperature sensing portion 3. As shown in FIG. 1, the gas flow path 27 after passing through the valve 10 is bypassed and communicates with the gas flow path 18 of the casing 33. Conventionally, the sensor portion is provided with a non-magnetic cap at a portion in contact with the bottom of the pot, and a temperature-sensitive portion at the center of the back surface of the cap where the magnetic permeability and the saturation magnetic flux density decrease when the temperature approaches the Curie temperature. However, in the present embodiment, the cap and the temperature sensing part are also used, and the temperature sensing part 3 itself is made of a temperature sensing metal.

Next, the sensor section 2 will be described with reference to an enlarged view shown in FIG. The attraction unit 8 has a rectangular parallelepiped magnet 13 having an N pole on the left side and an S pole on the right side, and a pair of a pair of suction surfaces which are in close contact with the left and right side surfaces of the magnet 13 and which are attached to the temperature sensing unit 3 at the upper end surface. Plate-like yokes 15a, 15b (hereinafter, when the left and right yokes 15a, 15b are not distinguished, the yoke 1
5) and a holding case 4 for fixing the magnet 13 and the yoke 15 and connecting to the connecting rod 11. The yoke 15 is provided with a rib R for positioning the magnet 13 on the lower side surface so that the magnet 13 does not shift upward on the side surface in contact with the magnet 13. The holding case 4 and the connecting rod 1
The connection rod 1 is connected to the connecting rod 1 so that the temperature sensing portion 3 and the suction surface of the yoke 15 can be in close contact even if the temperature sensing portion 3 in contact with the bottom of the pot is inclined.
The inclination to 1 has an appropriate degree of freedom.

Next, the lever 17 for transmitting the pressing operation force will be described. As shown in FIG. 1, the casing 33 is provided with a lever 17 that transmits a pressing operation force of the ignition button 19 to the suction unit 8. The ignition button 19 is advanced by a pressing operation at the time of ignition, and the connecting rod 11 is
Is moved in the direction in which the suction section 8 provided at the other end of the section comes into contact with the temperature sensing section 3 (upward in the figure). The lever 17 is divided into a lever arm 17a and a lever arm 17b, and is urged by a stroke-absorbing torque spring 18 so that the angle between the arms is maintained at a predetermined angle. Then, after the suction portion 8 comes into contact with the temperature sensing portion 3 by the pressing operation at the time of ignition, the lever 17 absorbs an extra pressing stroke.

Next, materials used for the sensor section 2 will be described. At present, the temperature-sensitive metal material practically used is made of an alloy of Fe, Ni, and Cr, and Cr is added to lower the Curie temperature.
It is below ° C. However, in this embodiment, since the temperature sensing part 3 detects the abnormal superheat temperature of 250 ° C. by directly abutting the bottom of the pot, the temperature sensing part 3 is made of Cr-free Fe62% and Ni38.
% Of the alloy, and a Curie temperature of 250%
Temperature. Thereby, the temperature sensing part 3 can directly contact the bottom of the pot to improve the sensitivity of the sensor part 2,
By not containing, the saturation magnetic flux density increases and the attraction force can be further increased. Further, conventionally, a thermosensitive ferrite which is baked with ceramic and is fragile and inferior in workability is used as the thermosensitive part 3 and a cap for protecting the thermosensitive ferrite is provided. ,
Uses temperature-sensitive metal that is strong against thermal shock and drop impact. Therefore, the cap and the temperature sensing part can be used as well, and the responsiveness is improved because the cap is not interposed. Further, the temperature-sensitive metal has a larger saturation magnetic flux density and a larger attraction force than the temperature-sensitive ferrite, and furthermore has a good heat conduction and therefore a good response.
Therefore, the accuracy of the detected temperature of the sensor unit 2 and the responsiveness can be improved. The yoke 15 is made of a ferromagnetic permalloy that is strongly magnetized in the direction of the magnetic field, and the holding case 4 is made of a non-magnetic Sm to prevent short-circuiting of magnetic flux lines.
US304 is used. On the other hand, the material of the magnet 13 of the attracting portion 8 is made of a rare earth cobalt magnet having a small change in magnetic force even at a high temperature.

Next, the operation of each part during ignition / extinguishing will be described (FIG. 1). In the stop state, the valve 10 is closed and the main valve 24 is closed because the adsorbing section 8 is separated from the temperature sensing section 3. When the ignition button 19 is pressed in this state, the ignition button 19 advances against the button spring 20 and
The spindle 23 is pushed rearward against the return spring 31 to open the main valve 24 and sequentially open the safety valve 32. Further, by the pressing operation on the ignition button 19, the suction section 8 is pressed against the temperature sensing section 3 via the lever 17. During this operation, the ignition switch 22 is turned on and the igniter of the combustion section starts operating. Then, by this series of operations, the raw gas is supplied to the combustion section via the main discharge port 26 and is ignited by the igniter. In addition, safety valve 32
, A current generated from the thermocouple 9 facing the combustion flame flows, and the safety electromotive force causes the safety valve 32 to be kept open.

On the other hand, the ignition button 19 moves forward by the ignition operation, the lever 17 swings and pushes up the connecting rod 11, and
The end of the yoke 15 is brought into contact with the temperature sensing part 3. York 15
When the end portion of the valve spring comes into contact with the temperature sensing portion 3, the suction force is applied to the valve spring 12.
To maintain the opening of the valve 10. When the user releases the hand after this pressing operation, the operation of the return spring 31 causes the spindle 23 and the ignition button 19 to open the main valve 24 by the push-push mechanism 21 to a position where the safety valve 32 can be freely closed. Returning, combustion is continued (the state shown in FIG. 1).

When the pot bottom temperature approaches a predetermined abnormal superheat temperature (250 ° C.) during combustion, the temperature-sensitive portion 3 having a Curie point approaches the Curie temperature, so that the magnetic permeability and the saturation magnetic flux density sharply increase. The yoke 15 and the temperature sensing part 3
Is smaller than the force of the valve spring 12, and the suction portion 8 is separated. When the suction part 8 and the temperature sensing part 3 are separated, the valve spring 1
2 closes the valve 10 and immediately stops the combustion. Therefore, the abnormal overheating state can be stopped, and a fire or the like can be prevented. When extinguishing a fire during combustion, the spindle 23 is returned by pressing and releasing the ignition button 19 again, and the main valve 24 is closed to extinguish the fire.

Here, the temperature sensing part 3, the magnet 13, and the yoke 15
The data of the attraction force obtained experimentally by changing the combination with the above will be described with reference to FIGS. 3 and 4. FIG. In addition, temperature sensing part 3, magnet 1
3. As shown in the graph, three combinations of three types of yoke 15 are prepared for comparison, A, B, and C. The A type is a type in which the N pole (or S pole) of the magnet 13 directly contacts the temperature sensing part 3, and the B type is a U-shaped yoke 1
5 is a type in which the S pole (or N pole) of the magnet 13 is in close contact with the bottom of the magnet 5, and both ends of the yoke 15 are magnetized to the S pole (or N pole) and contact the temperature sensing part 3. The C type has yokes 15 on both sides of a magnet 13 having N poles and S poles on the left and right.
And one end of the yoke 15 is N-pole (or S-pole),
The other end is of a type that is magnetized to an S pole (or an N pole) and contacts the temperature sensing portion 3. A, B, and C have the same temperature sensing part 3 and the same magnet 13, and the same contact area of the yoke 15.

FIG. 3 shows the attraction force (f) when the gap (t1) between the temperature sensing part 3 and the yoke 15 (or the magnet 13) is changed. In the case of type A, the attraction force gradually decreases in accordance with the size of the gap.
There is a gap between the magnet 13 and the N pole, and the attraction force is weak in the first place. Even if the gap between the temperature sensing part 3 and the yoke 15 is changed, the attraction force hardly decreases. On the other hand, the C type has a closed magnetic path when the temperature sensing part 3 and the yoke 15 are attracted, and a magnetic path is opened when a gap is formed, so that the attracting force is greatly changed. In the case of the C type, the material is not affected at all by the material of the cooking pot 1 when the magnetic flux is adsorbed in a normal temperature state to form a closed magnetic circuit. When the magnetic flux lines start to overflow from outside 3, the magnetic flux lines start to pass through the cooking pot 1.

The degree of influence of the material of the cooking pot 1 in the types A, B and C can be compared with the data of the attraction force (f) by the gap (t1) in FIG. The C type has the largest decrease in the attraction force due to the gap as compared with the A and B types. For example, assuming that the thickness of the temperature sensing portion 3 is 1 mm, there is a gap of 1 mm between the cooking pot 1 and the yoke 15, and the attraction force is half or less of the attraction force in the close contact state. That is, in the C type, even if the temperature sensing part 3 reaches the Curie point and the saturation magnetic flux density becomes 0, and the magnetic flux lines overflow and lead to the cooking pan 1 100%, the adsorption force between the cooking pan 1 and the yoke 15 is increased. Halve. On the other hand, in the A and B types, the attraction force at a gap of 1 mm does not decrease so much as compared with the attraction force in the close contact state. Therefore, if the iron cooking pot 1 is used, even if the temperature sensing part 3 reaches the Curie point and the saturation magnetic flux density becomes zero, the magnetic flux lines overflow and the attraction force between the cooking pot 1 and the yoke 15 remains. .
That is, the type C according to the present embodiment is less affected by the material of the cooking pot 1 than the types A and B.

FIG. 4 shows the suction force (f) when the temperature sensing part 3 is divided into right and left parts and the gap (t2) is changed. The A type has a lower adsorbing force as the gap becomes larger, and the B type has a weaker adsorbing force even when there is no gap in the temperature sensing section 3, and the adsorbing force gradually decreases as the gap becomes larger. On the other hand, the C type is a closed magnetic path at the time of attraction, and if there is a small gap, it becomes an open magnetic path and the attraction force is greatly reduced. Therefore, when the temperature of the temperature sensing part 3 partially rises and the temperature becomes uneven, and the saturation magnetic flux density decreases due to the temperature unevenness, the magnetic flux lines jump out of the temperature sensing part 3. The magnetic flux lines pass through the gap, which is the same as that of the magnetic flux lines. On the other hand, in the A and B types, even when the temperature sensing part 3 partially reaches the Curie temperature and the magnetic flux lines start to fly out or detour from the temperature sensing part 3, the attraction force does not decrease compared to the C type.
Therefore, in the C type according to the present embodiment, even if the temperature sensing part 3 partially reaches the Curie temperature, the attraction force is reduced and the safety device can be operated.

As described above, the safety device of the cooking device according to the present embodiment is not easily affected by the material of the cooking pot 1 and also accurately senses the temperature of the bottom of the cooking pot 1 and has good responsiveness. Further, when the yoke 15 and the temperature sensing part 3 are attracted to each other, the magnetic flux lines are changed from the magnet 13N pole to the left yoke 15b to the temperature sensing part 3 to the right when the left side surface of the magnet 13 is set to the N pole. The yoke 15a is closed by passing from the magnet 13S pole. Therefore, the magnetic flux lines are concentrated on the contact surface between the yoke 15 and the temperature sensing part 3, and a large attraction force is obtained. Further, since the magnetic flux lines pass through the temperature sensing part 3, even if the material of the cooking pot 1 is different, the suction power is not affected. Further, even if the magnetic flux lines passing through the cooking pot 1 increase near the Curie temperature, the influence of the material of the cooking pot 1 is small because the adsorption force is greatly reduced.

Further, the temperature sensing unit 3 comes into contact with the bottom of the cooking pot 1, and the heat of the cooking pot 1 is directly transmitted to the temperature sensing unit 3. Therefore, the temperature difference between the temperature sensing unit 3 and the cooking pot 1 is reduced, and the temperature sensing unit 3 can accurately detect abnormal overheating of the cooking pot 1. In addition, the temperature is not limited to the contact surface between the temperature sensing part 3 and the yoke 15, and when a part of the temperature sensing part 3 reaches a predetermined temperature, the magnetic permeability and the saturation magnetic flux density decrease, the magnetism is lost, and the temperature suddenly decreases. The suction force is reduced, and the yoke 15 is detached from the temperature sensing unit 3. That is, even when the temperature of the temperature sensing portion 3 is uneven and the temperature is partially increased, abnormal overheating can be accurately detected. Therefore, the temperature detection accuracy and the responsiveness in the safety device of the cooking appliance are improved.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and it is needless to say that the present invention can be implemented in various modes without departing from the gist of the present invention. It is. For example, magnet 1
The configuration is not limited to the configuration in which the yoke 15 is sandwiched between the magnets 3, and may be a U-shaped magnet having both ends at both ends. When a U-shaped magnet is used, the yoke 15 becomes unnecessary, and the sensor unit 2 can be made inexpensive.

The manual operation of pushing the ignition button 19 is limited to forcibly bringing the temperature sensing part 3 into contact with the suction part 8 to suck the suction part 8 and opening the valve body 10. Instead, a configuration may be adopted in which an actuator such as a solenoid for pushing the suction unit 8 is provided to open the valve body 10.

The adsorbing section 8 is not limited to closing the valve body 10 directly by detaching from the temperature sensing section 3 in conjunction with the valve body 10. A configuration may be adopted in which the valve body 10 is closed if it is detected and is in the detached state.

Although the embodiment of the present invention has been described as a device for preventing overheating when the stove is abnormal, the device may be configured as a device for preventing overheating of cooking equipment such as a rice cooker.

[0032]

As described in detail above, claim 1 of the present invention
According to the safety device for a cooking device described above, the temperature sensing portion directly abuts on the pot bottom of the cooking pot, so that it has an excellent effect of accurately sensing the temperature and improving the temperature detection accuracy and responsiveness.

According to the safety device for a cooking device according to the second aspect, even if the material of the cooking pot is different, it does not affect the attraction force, so that the temperature detection accuracy and the responsiveness can be improved.

According to the third aspect of the present invention, in addition to the effect of the second aspect, since the temperature sensing portion is in direct contact with the bottom of the cooking pot, the temperature can be accurately detected and the temperature can be detected. Accuracy and responsiveness can be improved.

According to the safety device for a cooker according to the fourth aspect, in addition to the effect according to the third aspect, the safety device can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a safety device for a cooking appliance as one embodiment.

FIG. 2 is an enlarged view of a sensor unit according to the embodiment of the present invention.

FIG. 3 shows an attraction force (f) and a gap (t) according to an embodiment of the present invention.
It is the graph obtained experimentally about 1).

FIG. 4 is a diagram showing an attraction force (f) and a gap (t) according to an embodiment of the present invention.
It is the graph obtained by experiment about 2).

FIG. 5 is a schematic configuration diagram of a conventional cooking device safety device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cooking pot 2 Sensor part 3 Temperature sensing part 4 Holding case 8 Suction part 10 Valve 11 Connecting rod 14 Burner 15a Yoke right 15b Yoke left

Claims (4)

[Claims] 1. A sensor made of a thermosensitive material having a Curie point whose heat is transferred from the cap to reach a predetermined temperature and whose magnetic permeability and saturation magnetic flux density decrease when the cap reaches a predetermined temperature. A temperature part, a suction part facing and separating from the temperature sensitive part using a permanent magnet, a valve body for opening and closing a gas flow path to a burner, and a valve when the suction part is detached from the temperature sensitive part. A safety device for a cooker provided with valve closing means for closing a body, wherein the cap abutting on a cooking pot is formed of a temperature-sensitive metal and also serves as the temperature-sensitive part. 2. A heat-sensitive material comprising a cap which contacts a pot bottom of a cooking pot to receive heat, and a heat-sensitive material having a Curie point at which a magnetic permeability and a saturation magnetic flux density are reduced when a predetermined temperature is reached by heat conduction from the cap. A temperature part, a suction part facing and separating from the temperature sensitive part using a permanent magnet, a valve body for opening and closing a gas flow path to a burner, and a valve when the suction part is detached from the temperature sensitive part. A safety device for a cooker provided with valve closing means for closing a body, wherein the adsorbing portion has a contact surface that comes into contact with and separates from the temperature sensing portion so as to contact the temperature sensing portion to form a closed magnetic path. A safety device for a cooking appliance, comprising two locations, one contact surface being magnetized to the N pole and the other contact surface being magnetized to the S pole. 3. The safety device for a cooking appliance according to claim 2, wherein the cap is formed of a temperature-sensitive metal and serves also as the temperature-sensitive portion. 4. The safety device for a cooking appliance according to claim 3, wherein the attraction portion is formed of a U-shaped magnet.