JP3375757B2 - Cooking device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooking device such as a table stove, and more particularly to detecting the temperature of the bottom of a cooking pot.
The present invention relates to a heating cooker having an overheating prevention function for preventing the temperature from becoming higher than a predetermined temperature. 2. Description of the Related Art Conventionally, in order to prevent a tempura fire, burning, etc., the temperature of the bottom of a cooking pot is detected by a thermistor, and if the detected temperature is higher than a predetermined temperature, heating is stopped. Cookers are known. For example, FIG.
Is provided with a thermistor 32 for detecting the temperature in the burner head 4, the bottom temperature of the cooking pot 6 is detected by the thermistor 32, and the controller 37 determines whether or not the detected temperature is equal to or higher than a set upper limit temperature. The opening / closing of the gas passage is controlled based on the determination result. In addition, the cooking device is provided with an extinguishing safety device that monitors the presence or absence of a combustion flame.
That is, the thermocouple 1 that generates an electromotive force by heating the combustion flame is provided in the burner head 4, and the controller 37 determines the presence or absence of a flame by determining whether the electromotive force generated by the thermocouple 1 is equal to or less than a predetermined value. Opening and closing of the gas passage is controlled based on the determination result. [0003] However, the conventional heating cooker is provided with a control circuit having a so-called extinguishment safety function for judging whether the electromotive force of the thermocouple is normal or not and controlling combustion. In addition, since the apparatus has both a control circuit having a so-called overheating prevention function for judging the pot bottom temperature detected by the thermistor and controlling combustion, it is very complicated and expensive. Accordingly, it is an object of the present invention to provide a heating cooker that solves the above-described problems and includes a mechanically operated inexpensive overheat prevention device. [0004] A heating cooker according to the present invention for solving the above-mentioned problems includes a burner for burning fuel gas, an on-off valve for opening and closing a gas flow path to the burner, and a combustion of the burner. A heating cooker comprising: a thermocouple that generates an electromotive force by heating with a flame; and combustion control means that stops the combustion by closing the on-off valve when the electromotive force level of the thermocouple drops below a predetermined value. A sensor that abuts against the bottom of the cooking pot and senses the temperature of the bottom of the pot to generate a predetermined displacement; and a secondary to the combustion flame that heats the thermocouple in conjunction with the displacement by the sensor. The gist of the present invention is to provide an air blocking means for preventing air supply . [0008] In the heating cooker of the present invention having the above-described structure, when a predetermined pot bottom temperature is reached, the air shut-off means reduces the temperature of the thermocouple to a combustion flame. Block the secondary air supply. That is, when the sensor section senses a predetermined pan bottom temperature, a predetermined displacement is generated, and the air shutoff means associated with this displacement prevents supply of secondary air to the combustion flame that heats the thermocouple. Then, the combustion flame is extinguished due to lack of secondary air, the generated electromotive force of the thermocouple drops to a predetermined value or less, and the combustion control means closes the on-off valve to stop combustion. Therefore, this cooking device does not require a complicated control circuit having an overheating prevention function. That is, a heating cooker having an overheating prevention function can be manufactured at low cost. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to further clarify the structure and operation of the present invention described above, a preferred embodiment of the cooking device of the present invention will be described below. First, before explaining the embodiment,
Reference Example will be described. FIG. 1 is a schematic configuration diagram of a heating cooker as a first reference example . At the center of a burner head 4 provided on the burner main body 3, a sensor unit 2 for detecting temperature is provided. The sensor unit 2 is provided by being urged upward by a pressing spring 5 and is in contact with the bottom of the cooking pot 6 placed on the burner main body 3 to detect the temperature of the bottom of the cooking pot. The burner head 4 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 main body 3 to form the main flame slot 27. The combustion flame formed in the main flame port 27 is supplied with secondary air from a secondary air hole 18 provided at the center of the burner body 3 and burns. The burner head 4 is provided with a heating flame port 14 for heating the thermocouple 1 so as to face the thermocouple 1. The thermocouple 1 generates an electromotive force by heating the combustion flame, and is electrically connected to a controller 37 that monitors the electromotive force. The controller 37 determines the presence or absence of a flame based on whether the electromotive force generated by the thermocouple 1 is equal to or less than a predetermined value. Further, the controller 37 is electrically connected to the main solenoid valve 16 and the main solenoid valve 17 for opening and closing the gas flow path, detects that the electromotive force has fallen below a predetermined value, and detects the main electromagnetic valve 16 and the main solenoid valve 17. To issue a valve closing command to stop combustion. The sensor section 2 is provided with a non-magnetic cover 7 at a portion in contact with the bottom surface of the cooking pot 6, and a temperature-sensitive ferrite 8 whose magnetism changes according to temperature inside the cover 7, and a temperature-sensitive ferrite 8. And a magnet 9 which is attracted and desorbed in the opposite direction. Further, one end is fixed to the magnet 9, and a push rod 10 that moves up and down integrally with the magnet 9 is provided. This stick 10
Is provided with a return spring 11 for urging the magnet 9 in the direction of detachment from the temperature-sensitive ferrite 8. Utilizing the fact that when the temperature reaches a predetermined temperature, the magnetism of the temperature-sensitive ferrite 8 changes from ferromagnetic to paramagnetic, and this return spring 11 overcomes the attraction force between the temperature-sensitive ferrite 8 and the magnet 9 to cause the magnet 9 to be heated. The push rod 10 is provided with a butt seat 21 for transmitting a stroke, and one end of a seesaw lever 12 is provided in contact with the butt seat 21. One end of a shield plate 13 provided in a gap between the thermocouple 1 and the heating flame port 14 is in contact with the other end of the lever 12 so as to be vertically movable. The shield plate 13 linked to the state of the attraction / detachment of the magnet 9 is set at the following relational position. First, when the magnet 9 and the temperature-sensitive ferrite 8 are attracted, the shielding plate 13
Are set so as not to block the heating flame of the thermocouple 1. Further, when the magnet 9 separates from the temperature-sensitive ferrite 8, the push rod 10 is pushed down by the return spring 11, and pushes up the shielding plate 13 via the lever 12, so that the positional relationship for shielding the heating flame of the thermocouple 1 is established. Provided. Therefore,
When the sensor section 2 detects a temperature equal to or higher than a predetermined temperature, the magnet 9 separates from the temperature-sensitive ferrite 8, the push rod 10 descends, the shielding plate 13 rises, and the heating flame is shielded. Then, the electromotive force of the thermocouple 1 decreases, and the controller 37 detects that the electromotive force is equal to or less than the predetermined electromotive force, closes the main electromagnetic valve 16 and the original electromagnetic valve 17, and closes the gas flow path. At a position facing the other end of the push rod 10, a set lever 24 for setting the sensor section 2 to a temperature sensing state is provided. The set lever 24 is provided with a setting knob 23 for performing a return operation and a release operation of the overheat prevention function. Further, the set lever 24 is provided with a lever spring 22 which is stronger than the return force of the return spring 11, and the set lever 24 is vertically moved upward or downward by the operation of the setting knob 23. When the setting knob 23 is lowered downward, the overheating prevention function is released, and when the setting knob 23 is lowered and then raised, the overheating prevention function is set. That is, when the setting knob 23 is lowered, the magnet 9 is pressed against the temperature-sensitive ferrite 8 and is attracted by the lever spring 22 provided on the set lever 24. This state is due to the strong lever spring 22
Since the push rod 10 is pushed up by the spring force, no stroke occurs in the push rod 10 even when the pan bottom temperature reaches a predetermined temperature. Therefore, the lower setting knob 23
The position is a release operation position of the overheat prevention function, and is used for disabling the overheat prevention function when high-temperature cooking at a predetermined temperature or more is required. In this state, when the setting knob 23 is pushed up, the magnet 9 and the temperature-sensitive ferrite 8 remain adsorbed, the shielding plate 13 is maintained at a position where the heating flame of the thermocouple 1 is not blocked, and the sensor section 2 is heated. Set to sensing state. That is, since the magnet 9 is maintained in the state of being attracted to the temperature-sensitive ferrite 8 unless an abnormal temperature is sensed, the return operation of the overheat prevention function is performed by forcibly pressing and attracting the lever spring 22.
All you have to do is release the spring force. Therefore, the operation of setting or canceling the overheating prevention function before cooking can be easily performed by simply selecting the upper and lower positions of the setting knob 23. If the overheat prevention device is activated upon detecting an abnormal temperature, the magnet 9 separates from the temperature-sensitive ferrite 8 and the overheating prevention function is not activated until the temperature detected by the temperature-sensitive ferrite 8 drops below a predetermined temperature. Recovery is not possible, and the user is urged to eliminate the abnormal state, which is safe. Further, when the overheat prevention function is restored after the pan bottom temperature falls below the predetermined temperature, the setting knob 23 is once depressed downward to the release position, and then simply raised upward to return to the return position. It can be carried out. Next, a second reference example will be described with reference to FIG. The sensor unit 2 for sensing the temperature of the bottom of the pot is the same as that of the first embodiment, so that the same reference numerals are given to the drawings and the duplicated description will be omitted. The second reference example is different from the first reference example in that the heating flame to the thermocouple 1 is cut off, but the heating flame is not cut off and the thermocouple 1 itself is moved out of the range of the heating flame. Features. The thermocouple 1 is fixed by a TC mounting bracket 26, and
It is fixed so as to slide integrally with the up and down movement of. The connection fitting 20 which is linked to the state of the attraction / removal of the magnet 9 is set at the following relational position. First, when the magnet 9 and the temperature-sensitive ferrite 8 are attracted, the connecting metal 20
Are provided in a positional relationship that holds the thermocouple 1 within an appropriate heating range of the heating flame. Further, the magnet 9 is a thermosensitive ferrite 8
When detached from the connecting member 20, the connection fitting 20 is provided in a positional relationship in which the thermocouple 1 is moved out of the heating range with the movement of the push rod 10. Therefore, when the temperature of the pot bottom reaches a predetermined temperature or higher, the force of the return spring 11 of the sensor unit 2 causes the magnet 9 to separate from the temperature-sensitive ferrite 8 and push down the push rod 10. At the same time, the connection fitting 20 that moves integrally with the push rod 10 moves the thermocouple 1 out of the heating range of the heating flame. Then, the heating flame cannot heat the thermocouple 1, reducing the electromotive force of the thermocouple 1 and closing the gas flow path. Next, an embodiment of the present invention will be described with reference to FIG. Examples of the present invention is different from the first reference example, the
While the reference example 1 blocks the heating flame to the thermocouple 1, the embodiment of the present invention prevents the secondary air supply to the heating flame of the thermocouple 1 and indirectly extinguishes the heating flame. It is characterized by: A heating flame port 14 for heating the thermocouple 1 is provided on the upper surface of the burner head 4 so as to face the thermocouple 1.
The heating flame formed in the heating flame port 14 is supplied to the burner main body 3.
The secondary air is supplied from a secondary air hole 18 provided at the center of the fuel cell and burns. Also, the push rod 10 from the sensor unit 2
A closing plate 19 that opens and closes the secondary air hole 18 is provided on the same axis. The closing plate 19 is provided so as to open the secondary air hole 18 when the magnet 9 and the temperature-sensitive ferrite 8 are adsorbed, and to close the secondary air hole 18 when the magnet 9 is separated from the temperature-sensitive ferrite 8. Can be Accordingly, when the temperature of the pot bottom reaches a predetermined temperature or more, the push rod 10 from the sensor unit 2 returns to the return spring 1.
As a result of being pushed down by one force, a secondary air hole 18 for supplying secondary air to the heating flame of the thermocouple 1 forms a closing plate 19.
Blocked by Then, the heating flame of the thermocouple 1 disappears due to the shortage of the secondary air, and the electromotive force of the thermocouple 1 decreases to close the gas passage. In each of the first and second embodiments and the embodiment , a mechanically operated overheat prevention function is provided, and a dedicated control circuit for the overheat prevention function is not required. Can be used as is. Therefore, a heating cooker provided with an inexpensive overheat prevention device can be provided. Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and can be implemented in various modes without departing from the gist of the present invention. It is. For example, the heating cooker according to the present embodiment electrically monitors the generated electromotive force of the thermocouple 1 by the controller 37 and makes the main electromagnetic valve 16 and the original electromagnetic valve 17 provided in the gas passages easy to understand. Although the heating safety device controls the opening and closing of the heater, the magnet safety valve is manually opened, and when the sensor detection temperature is equal to or higher than the set upper limit temperature, the generated electromotive force of the thermocouple 1 decreases, and the valve is held open. The force may disappear and the magnet safety valve may be closed. Further, when the temperature reaches a predetermined temperature, the sensor unit 2 that generates a predetermined stroke on the push rod 10 is not limited to the temperature-sensitive ferrite 8 and the magnet 9, but expands and deforms depending on temperature, for example, Thermoelements, bimetals, and shape memory alloys may be used. The set lever 24 is not limited to snapping up or down by the operation of the setting knob 23, but is provided so as to always return to the set position in the detection state by the lever spring 22. May be provided with a lock portion that is locked only at the release position. Further, the sensor section 2 is not limited to the case where the magnet 9 separates from the temperature-sensitive ferrite 8 when the predetermined temperature is reached, so that a predetermined stroke is suddenly generated on the push rod 10. That is, a stroke may be generated in proportion to the temperature, and the generated electromotive force of the thermocouple 1 may be reduced as the temperature approaches a predetermined temperature. For example, a configuration using thermowax may be used . As described in detail above, the heating cooker of the present invention does not require a complicated control circuit for judging the bottom temperature of the pot and controlling the combustion, and therefore has a function of preventing overheating. An excellent effect that an inexpensive heating cooker can be manufactured inexpensively is achieved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram of a heating cooker as a first reference example . FIG. 2 is a schematic configuration diagram of a heating cooker as a second reference example . FIG. 3 is a schematic configuration diagram of a heating cooker according to an embodiment of the present invention . FIG. 4 is a schematic configuration diagram of a conventional heating cooker. [Description of Signs] 1 Thermocouple 2 Sensor part 7 Cover 8 Temperature-sensitive ferrite 9 Magnet 10 Push rod 12 Lever 13 Shielding plate 23 Setting knob 37 Controller

Claims (1)

(57) [Claims 1] A burner for burning fuel gas, an on-off valve for opening and closing a gas flow path to the burner, and a thermocouple for generating an electromotive force by heating the burner with a combustion flame And a combustion control means for closing the on-off valve to stop combustion when the electromotive force level of the thermocouple drops below a predetermined value. A sensor unit that senses a pan bottom temperature and generates a predetermined displacement; and an air shutoff unit that interlocks secondary air supply to the combustion flame that heats the thermocouple in conjunction with the displacement by the sensor unit. A cooking device characterized by the above-mentioned.