JP2007292409A - Cooking stove with pan bottom thermosensitive sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooking stove with a pan bottom thermosensitive sensor capable of reducing damage of a thermosensitive head and a bottom of a heated container, and generation of unpleasant noise by reducing the interference therewith in shaking a pan for cooking, while making an overheat preventing function effective. <P>SOLUTION: A typical constitution of this cooking stove with the pan bottom thermosensitive sensor kept into contact with a bottom surface of the heated container placed on a trivet to detect its temperature, comprises the thermosensitive head which is vertically movable, a head energizing means for energizing the thermosensitive head upward, a lifting base supporting the thermosensitive head and the head energizing means, and vertically movable, and a base control means for setting down a position of the lifting base, and the base control means can set down the position of the lifting base during burning. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a stove provided with a pan bottom thermal sensor that detects the temperature by contacting the bottom surface of a heated container placed on Gotoku.

  Conventionally, a stove that cooks by heating a heated container such as a pan has been equipped with a pan bottom thermal sensor that detects the temperature by contacting the bottom of the pan, and when the pan bottom temperature exceeds the set temperature, the heating power is reduced. Products with overheating prevention functions that weaken or automatically extinguish fire are provided. For example, as shown in Japanese Patent Application Laid-Open No. 07-269871 (Patent Document 1), these stoves have a thermal head that can move up and down at the center of an annular burner, and a thermal sensor such as a thermistor at the upper end of the thermal head. It is configured to urge upward. When the pan is placed on Gotoku, the thermal head sinks against the urging force due to the weight of the pan, and always comes into contact with the bottom of the pan to detect its temperature.

  Conventionally, this type of pan-bottom thermal sensor is often used for cooking tempura, etc., in a two- or three-burner stove used at home, and is often used for cooking tempura. It was not attached to many high power burners. However, in order to improve safety, in recent years, a configuration in which a pan-bottom thermal sensor is attached to all three outlets including a high-power burner has been seen.

However, it is assumed that the high-burner burner performs cooking at a higher temperature, such as fried food, in addition to cooking such as boiled food and fried food. At this time, if the heating power is simply controlled by the temperature at the bottom of the pan, the overheat prevention function is activated at about 250 ° C. because of the setting during cooking in the pan. Therefore, although the user is cooking while holding the pan and confirming safety, the overheat prevention function is activated, and there is a possibility that high-temperature cooking as expected cannot be performed. In view of this, conventionally, there have been proposed and provided a configuration in which a function defining switch is provided so that the overheat prevention function does not work, a configuration in which a set temperature for performing thermal power control is changed by a mode switching operation by a user, and the like. Japanese Patent Laid-Open No. 06-002839 (Patent Document 2) proposes a configuration in which a human body detection sensor is provided and the overheat prevention function is not operated under the monitoring of the user.
Japanese Patent Application Laid-Open No. 07-269871 Japanese Patent Laid-Open No. 06-002839

  However, since the thermal head having the above-described configuration is in a state in which the pan is not placed on the virtues and protrudes upward from the virtues by the biasing force, the thermal head follows the bottom surface even if the pan is lifted to some extent. For this reason, for example, when cooking in a pan with fried food, the thermal head and the bottom of the pan will always rub against each other, producing not only an unpleasant sound, but scratching the pan bottom or damaging the thermal head. There is a risk of inviting.

  On the other hand, even if you say hot pot food in a bite, it is convenient not to activate the overheat prevention function when cooking at high temperature like Chinese food stir-fry, but there are also many hot pot food at medium and low temperatures. In such a case, it is preferable to activate the overheat prevention function. In other words, there is a demand for reducing the friction between the thermal head and the bottom of the pan while cooking the overheating prevention function.

  Accordingly, the present invention reduces the interference between the thermal head and the bottom of the container to be heated during cooking in a pot while enabling the overheat prevention function, and can reduce the occurrence of these damages and unpleasant sounds. An object is to provide a stove with a thermal sensor.

  A typical configuration of a stove with a pan bottom thermal sensor according to the present invention is a thermosensitive that can move up and down in a stove including a pan bottom thermal sensor that detects the temperature by contacting the bottom of a heated container placed on Gotoku. A head; a head urging means for urging the thermal head upward; a lifting base that supports the thermal head and the head urging means and is movable up and down; and a base defining means that defines the position of the lifting base. The base defining means is characterized in that the position of the elevating base can be defined during combustion. Although the thermal head moves up and down with respect to the lifting base, the movable range of the thermal head with respect to the five virtues changes as the lifting base further moves up and down. During combustion, the position of the elevating base is temporarily defined, and the height at which the upper end of the thermal head's movable range protrudes above the five virtues is lowered, so that the pan bottom and the sensor can be rubbed just by lifting the pan slightly. It is possible to reduce friction and collision with each other.

  Further, the base urging means for urging the elevating base upward may be provided, and the base defining means may be configured to define at least the upper limit of the movable range of the elevating base at an arbitrary position. Thereby, the position of the elevating base can be defined with a simple configuration.

  Moreover, it is preferable to provide the position sensor which detects the position of a thermal head. Furthermore, when the base defining means regulates (fixes) the vertical movement of the elevating base, it is preferable to regulate after detecting the descent of the thermal head. In order to make the overheat prevention function work effectively, when the thermal head has been raised for a predetermined time or more, it is preferable to cancel the regulation of the base defining means and to perform the normal operation.

  The base defining means preferably includes a ratchet mechanism that allows the base to move downward and restricts the upward movement. Thereby, even when a heated container having a different shape is placed on Gotoku, the movable range of the thermal head can be adjusted following this.

  The base defining means may include an actuator that pulls down the base. By providing an actuator that actively pulls down the thermal head, the thermal head can be pulled down to the retracted state at any time, regardless of the state of placement of the heated container.

  According to the present invention, in the stove provided with a pan bottom thermal sensor, by defining the position of the lift base during combustion, the upper limit of the movable range of the thermal head is lowered, and the thermal head and the heated container during pan-shaking cooking Interference with the bottom of the can be reduced. Thereby, while making the overheat prevention function effective, damage to the thermal head and the bottom of the heated container can be reduced, and the occurrence of unpleasant sound due to these rubbing can be reduced.

{First Example}
A first embodiment of a stove with a pan bottom thermal sensor according to the present invention will be described. FIG. 1 is a diagram illustrating the configuration of a stove with a pan-bottom thermal sensor, FIG. 2 is a diagram illustrating a state in which a heated container is placed on the virtues, and FIG. 3 is a diagram illustrating a state in which pot-shaking cooking is performed. FIG. 4 is a view for explaining a state in which the thermal head and the lifting base are lowered and protruded due to a difference in elastic force between the head biasing means and the base biasing means. In addition, the numerical values such as specific materials and dimensions described in this embodiment are examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified.

  In the stove shown in FIG. 1, a five virtue 11 for placing a heated container such as a pan on a burner 10 is installed. The burner may be an internal flame burner that emits flame from the outer periphery to the center as shown in the figure, or an external flame burner that emits flame in an annular shape from the center to the outside.

  A thermal head 12 is installed in the center of the burner 10. The thermal head 12 is configured such that the elevating base 13 is slidably inserted therein and is movable up and down. A flange 13 a is provided at the upper end of the elevating base 13, and the upper limit of the movable range of the thermal head is defined by engaging with the lower end of the thermal head 12. Further, a compression spring 14 (pressing spring) as an example of a head biasing means is provided between the flange 13a and the inside of the thermal head 12, and biases the thermal head 12 upward.

  A heat collecting plate 15 made of a material having high thermal conductivity is attached to the upper end of the thermal head 12, that is, the surface contacting the heated container. The thermal head 12 has a double-cylinder structure and prevents the heat collecting plate 15 from being directly heated by a flame. A thermistor 16 as an example of temperature detecting means is attached to the inner surface of the heat collecting plate 15. The lead wire 16a connected to the thermistor 16 is connected to a temperature detection unit 22 of the control unit 20 described later. The thermal head 12 is inserted through a substantially cylindrical outer cylinder 19 to prevent the thermal head 12 from being directly exposed to the flame ejected from the burner 10 and to protect the mechanism of the vertical movement of the thermal head 12. It has a configuration.

  A rack 13 b having gear teeth in the vertical direction is provided at the lower part of the elevating base 13 and meshes with a pinion 31 connected to the brake 30. A tension spring 34 as an example of a base urging means is provided between the arm 13c of the elevating base 13 and the housing frame 33, and urges the elevating base 13 upward. That is, the lifting base 13 is biased upward by the tension spring 34 with respect to the housing frame 33, and the thermal head 12 is biased upward by the compression spring 14 with respect to the lifting base 13. Then, by operating the brake 30, the elevating base 13 can be defined at an arbitrary position. At this time, the thermal head 12 can move up and down.

  The control unit 20 includes an IC 21 that executes a control program, a temperature detection unit 22 connected to the thermistor 16, an ignition control unit 23 connected to the ignition switch 23a, a thermal power instruction unit 24 connected to the thermal power instruction switch 24a, a gas A thermal power control unit 25 connected to an electromagnetic valve 25a for controlling the flow rate of the gas and a regulation control unit 26 connected to a regulation switch 26a. The regulation switch 26 a is a switch for regulating at least the upper limit of the movable range of the elevating base 13. Actually, the temperature detection unit 22, the ignition control unit 23, the thermal power instruction unit 24, the thermal power control unit 25, and the regulation control unit 26 are realized as software, stored in the ROM of the IC 21 as an embedded program, and read and executed during operation. .

  First, the normal operation of the stove having the above configuration will be described. As shown in FIG. 2A, when the pan 1 as an example of the container to be heated is placed on the virtues 11, the thermal head 12 and the elevating base 13 are both lowered by the weight of the pan 1. As shown in FIG. 2B, when the pan 1 has a bottom protruding like a Chinese wok, the upper end of the thermal head 12 sinks below the upper end of the virtues 11.

  At this time, the heat collecting plate 15 is in contact with the bottom of the pan. When the user operates the ignition switch 23a and the thermal power instruction switch 24a, the IC 21 detects this from the ignition control unit 23 and the thermal power instruction unit 24, and controls the electromagnetic valve 25a via the thermal power control unit 25 to flow out the gas. Meanwhile, heating is started by controlling a spark plug (not shown). The temperature at the bottom of the pan is transmitted to the thermistor 16 via the heat collecting plate 15, and the IC 21 obtains temperature information via the temperature detector 22. Then, as an overheat prevention function, when the detected temperature exceeds a predetermined temperature (for example, 250 ° C.), the IC 21 reduces the gas flow rate through the thermal power control unit 25 to weaken the thermal power, or stops the gas to extinguish the fire.

  Next, operations characteristic of the present invention will be described with reference to FIG. 3 and FIG. The user operates the regulation switch 26a in a state where the pan 1 is placed on the five virtues 11 when he / she wants to cook the pan such as fried food. When the IC 21 detects this via the regulation control unit 26, the brake 30 is actuated to regulate the vertical movement of the elevating base 13 by the engagement of the rack 13 b and the pinion 31. Then, as shown in FIG. 4A, the thermal head 12 can be moved up and down by the height of the thermal head 12 that has sunk relative to the lifting base 13 (see FIG. 4A). H1). Therefore, as shown in FIG. 3, the upper limit of the movable range of the thermal head 12 is lowered, and the pan bottom and the thermal head 12 do not rub just by lifting the pan 1 a little, even though the burner 10 is burning. Accordingly, it is possible to reduce damage to the thermal head 12 and the bottom of the pan 1 during pan-shaking cooking, and to reduce the occurrence of unpleasant sounds due to these rubbing.

  Since the upper end of the thermal head 12 protrudes upward from the virtues 11, the heat collecting plate 15 of the thermal head 12 comes into contact with the pan bottom when the pan 1 is placed on the virtues 11. Therefore, the overheat prevention function can be operated continuously, and safety can be ensured. Here, since the brake 30 is configured to be able to define the elevating base 13 at an arbitrary position, the elevating base 13 has a shape of the bottom of the pan 1 (a raised bottom, a flat bottom, a deep bottom such as a wok). Accordingly, it can be defined at the position where the thermal head 12 and the lift base 13 are sunk. From this, even if it is a heated container of any shape, when cooking in a pot, if it is lifted by the same amount, it will not rub, and the user can always obtain the same feeling of use.

  Here, the manner in which the thermal head 12 and the lifting base 13 sink and protrude due to the difference in elastic force (spring constant) between the compression spring 14 and the tension spring 34 will be described with reference to FIG. FIG. 4A shows the case where the compression spring 14 has a larger spring constant, and FIG. 4B shows the case where the tension spring 34 has a larger spring constant. In both cases, the amount of subsidence (height) of the thermal head 12 when the pan 1 is placed is assumed to be equal.

  As shown in FIG. 4A, when the compression spring 14 built in the thermal head 12 has a larger spring constant, when the thermal head 12 sinks by the pan 1, the compression spring 14 is deformed (shrinks) to a small extent and is pulled. The spring 34 is greatly deformed (stretched). When the elevating base 13 is regulated by the brake 30 in the sinked state, the height H1 at which the thermal head 12 can rise when the pan 1 is lifted is small.

  On the other hand, when the compression spring 14 has a smaller spring constant as shown in FIG. 4B, when the thermal head 12 sinks due to the pan 1, the compression spring 14 is greatly deformed and the tension spring 34 is deformed small. And if the raising / lowering base 13 is regulated in the sinked state, the height H2 at which the thermal head 12 can rise when the pan 1 is lifted increases.

  From these facts, it is understood that the spring constant of the compression spring 14 should be made larger than that of the tension spring 34 in order to make the upper limit of the movable range of the thermal head 12 as low as possible after the lifting base 13 is regulated by the brake 30. . On the other hand, since it is conceivable to replace the pan even in a restricted state, the spring constant of the compression spring 14 may be reduced in order to cope with various shapes of the pan bottom. That is, the protruding amount of the thermal head 12 in the restricted state can be adjusted by the ratio of the spring constants of the compression spring 14 and the tension spring 34.

  As described above, according to the present invention, in the stove equipped with the pan bottom thermal sensor, by reducing the interference between the thermal head and the bottom of the heated container during cooking of the pan, while enabling the overheating prevention function, Damage to the thermal head and the bottom of the container to be heated can be reduced, and the occurrence of unpleasant sound due to these rubbing can be reduced.

{Second Example}
A second embodiment of the stove with a pan bottom thermal sensor according to the present invention will be described. FIG. 5 is a diagram for explaining a main part of a stove with a pan-bottom thermal sensor according to the second embodiment, where the same parts as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  In the said 1st Example, the user operated the regulation switch 26a in the state which mounted the pan 1 on the virtues 11, and demonstrated that the raising / lowering base 13 was controlled with the brake 30. FIG. However, it is not guaranteed that the user operates in a state where the pan 1 is placed. Even in this case, since the thermal head 12 sinks due to the action of the compression spring 14, the pan 1 does not roll over, but the upper limit of the movable range of the thermal head 12 cannot be lowered, and the effect of the present invention cannot be obtained. There is a fear.

  Therefore, the present embodiment shows an example of a configuration in which only the upper limit of the movable range of the lifting base 13 is defined (so that it can be moved downward) even after the vertical movement of the lifting base 13 is defined.

  In the configuration shown in FIG. 5A, a ratchet mechanism 32 is provided between the brake 30 and a pinion 31 provided on the brake 30. The ratchet mechanism 32 can restrict the rotation of the pinion 31 in one direction, permit the downward movement of the lift base 13 when the brake 30 is operated, and restrict the upward movement. By releasing the brake 30, the ratchet mechanism 32 and the pinion 31 are rotatable in both directions, and the elevating base 13 can be moved up and down.

  The configuration shown in FIG. 5B includes a lock mechanism 35 as an example of a base defining means. The lock mechanism 35 includes a solenoid 35a, and is configured to be able to advance and retract the hook 35b and the hook biasing spring 35c. The hook 35b can be advanced and retracted by a hook biasing spring 35c and has an inclined surface on the upper side. Therefore, when the hook 35b meshes with the rack 13b, the hook 35b advances and retreats when the rack 13b moves downward, and this is permitted, and when the rack 13b moves upward, the mesh engages with this. not allowed. In the above configuration, when an instruction from the regulation switch 26a is transmitted to the IC 21, the IC 21 activates the solenoid 35a to bias the hook 35b to the rack 13b. If the lifting base 13 sinks by the weight of the pan 1 before and after that, the lifting of the lifting base 13 is restricted until the solenoid 35a is released thereafter.

  As described above, the base defining means defines only the upper limit of the movable range of the elevating base 13 and permits the lowering, so that the pan 1 is placed when the user operates the defining switch 26a. Regardless of whether or not it is replaced with a pan having a different bottom shape, the interference between the thermal head and the bottom of the container to be heated can be reduced appropriately when cooking in a pan.

{Third embodiment}
A third embodiment of the stove with a pan bottom thermal sensor according to the present invention will be described. FIG. 6 is a diagram for explaining a main part of the stove with a pan bottom thermal sensor according to the third embodiment, where the same reference numerals are assigned to the same portions as those in the first embodiment, and the description is omitted.

  In this embodiment, a sensor for detecting the position of the thermal head 12, particularly a position sensor for detecting whether or not the thermal head 12 is at the upper end of the movable range with respect to the lifting base 13 is provided.

  As shown in FIG. 6A, the thermal head 12 is provided with a flag 36, and the lift base 13 is provided with a position sensor 37 made of a photo interrupter. When the thermal head 12 sinks, the flag 36 shields the position sensor 37, and the IC 21 can detect this. The position detection of the thermal head 12 by the position sensor 37 can be used for two controls.

  As the first control, when the user operates the regulation switch 26a, the IC 21 first determines a signal from the position sensor 37. When it is determined that the thermal head 12 is at the upper end, that is, when the pan 1 is not placed on the virtues 11, the brake 30 can be controlled not to operate. Thereby, it can prevent that this raises / lowers base 13 in the state which is not sinking.

  As the second control, the brake 30 can be released when the pan 1 is replaced. That is, as shown in FIG. 6B, consider a case where the elevating base 13 is regulated using a pan 1a with a protruding bottom, such as a Chinese wok, and then replaced with a flat pan 1b like a frying pan. Then, there is a possibility that the thermal head 12 whose upper end of the movable range is regulated does not come into contact with the bottom of the pan, and is overheated by the flame from the burner 10, and there is a possibility that the overheat prevention function operates and limits the thermal power. is there.

  Therefore, in the state where the lifting base 13 is restricted, if the state where the thermal head 12 is at the upper end (the state where the thermal head 12 is not in contact with the pan bottom) continues for a predetermined time or longer, the restriction by the brake 30 is released. To do. Thereby, the thermal head 12 can be reliably contact | abutted to the pan bottom, and the operation | movement of an overheat prevention function can be ensured. When the thermal head 12 is still at the upper end even after the brake 30 is released, it means that the pan 1 is not placed, so that the thermal power is reduced based on the normal overheat prevention function. Limit or stop.

  By providing the position sensor 37 for detecting the position of the thermal head 12 as described above, the elevating base 13 can be regulated after the lowering of the thermal head 12 is detected, and the thermal head 12 is attached to the heated container. When not in contact, the brake 30 can be released and the overheat prevention function can be effectively operated.

{Other embodiments}
In each of the above embodiments, the means for sinking the lifting base 13 depends on the weight of the pan 1. However, the present invention is not limited to this, and may be configured to actively lower the elevating base 13.

  FIG. 7 is a diagram for explaining an example of a configuration for actively lowering the lifting base 13 and includes a solenoid 40 as an example of an actuator for lowering the lifting base 13. The arm 40 a of the solenoid 40 can take two or more postures, and the tip thereof is connected to the elevating base 13 by a wire 41.

  According to the said structure, since the raising / lowering base 13 can be actively pulled down irrespective of whether the pan 1 is mounted, the position of the raising / lowering base 13 can be prescribed | regulated at arbitrary timings.

  In each of the above embodiments, the tension spring 34 is provided to move the elevating base 13 upward. However, a mechanism having a driving force may be used as the base urging means for urging the lifting base upward. FIG. 8 is a diagram for explaining an example provided with base urging means for urging the lifting base upward by a driving force.

  FIG. 8 shows a configuration in which a stepping motor 43 is provided and a pinion 43 a is engaged with the rack 13 b of the lifting base 13. Therefore, the elevating base 13 is moved by the driving force of the stepping motor 43 both in ascending and descending. Since the stepping motor can fix the rotor unless the stator to be excited is changed, it is convenient for maintaining a constant posture. Thereby, since the position of the raising / lowering base 13 can be fixed not only in two places up and down but in arbitrary positions, further detailed control is possible.

  Various other configurations may be considered as the base defining means. In a stove equipped with a pan-bottom thermal sensor, a lift base that supports the thermal head and the head biasing means and can move up and down, and the position of the lift base during combustion And a base defining means for defining the above-mentioned values belong to the category of the present invention.

  In each of the above embodiments, the overheat prevention function is always operated. However, it may be configured such that the overheat prevention function can be canceled at the same time while defining the position of the elevating base 13. Thereby, even when cooking in a pot such as stir-fried food and high-temperature cooking, the heating power is not limited, and the work can be performed comfortably.

  INDUSTRIAL APPLICABILITY The present invention can be used as a stove provided with a pan bottom thermal sensor that detects the temperature by contacting the bottom surface of the heated container.

It is a figure explaining the structure of the stove with a pan bottom thermal sensor. It is a figure explaining the state which mounted the to-be-heated container on Gotoku. It is a figure explaining the state which is performing the pot shake cooking. It is a figure explaining the state of the sinking and protrusion of a thermal head and a raising / lowering base by the difference in the elastic force of a head biasing means and a base biasing means. It is a figure explaining the principal part of the stove with a pan bottom thermal sensor which concerns on 2nd Example. It is a figure explaining the principal part of the stove with a pan bottom thermal sensor which concerns on 3rd Example. It is a figure explaining the example of the structure which pulls down the raising / lowering base positively. It is a figure explaining the example provided with the base biasing means which biases a raising / lowering base upward with a driving force.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Pan 10 ... Burner 11 ... Gotoku 12 ... Thermal head 13 ... Elevating base 13a ... Flange 13b ... Rack 13c ... Arm 14 ... Compression spring 15 ... Heat collecting plate 16 ... Thermistor 16a ... Lead wire 19 ... Outer cylinder 1b ... Pan 20 ... Control unit 21 ... IC
22 ... Temperature detection unit 23 ... Ignition control unit 23a ... Ignition switch 24 ... Heat power instruction unit 24a ... Heat power instruction switch 25 ... Heat power control unit 25a ... Electromagnetic valve 26 ... Regulation control unit 26a ... Regulation switch 30 ... Brake 31 ... Pinion 32 ... Ratchet mechanism 33 ... housing frame 34 ... tension spring 35 ... lock mechanism 35a ... solenoid 35b ... hook 35c ... hook biasing spring 36 ... flag 37 ... position sensor 40 ... solenoid 40a ... arm 41 ... wire 42 ... solenoid 43 ... stepping motor 43a ... Pinion

Claims (5)

In a stove equipped with a pan bottom thermal sensor that detects the temperature by contacting the bottom of the heated container placed on Gotoku,
A thermal head that can move up and down;
Head biasing means for biasing the thermal head upward;
An elevating base that supports the thermal head and the head biasing means and is movable up and down;
Base defining means for defining the position of the elevating base,
The stove with a pan bottom thermal sensor, wherein the base defining means is capable of defining the position of the elevating base during combustion. Base urging means for urging the elevating base upward;
The stove with a pan bottom thermal sensor according to claim 1, wherein the base defining means defines at least an upper limit of a movable range of the elevating base at an arbitrary position.   The stove with a pan bottom thermal sensor according to claim 2, further comprising a position sensor for detecting the position of the thermal head.   The cooktop with a pan bottom thermal sensor according to claim 2, wherein the base defining means includes a ratchet mechanism that permits the base to move downward and restricts the upward movement. The pan bottom thermal sensor according to claim 2, wherein the base defining means includes an actuator for lowering the elevating base.

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