JP2010153059A - High-frequency heating element, cooking appliance for high-frequency heating apparatus, and high-frequency heating apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem in a conventional high-frequency heating element that, it is inferior in durability-reliability when it is good at temperature-raising performance, and it is inferior in temperature-raising performance when it has high durability-reliability, and there have been no heating elements having both temperature-raising performance and durability-reliability. <P>SOLUTION: By structuring the high-frequency heating element 3 with a magnetic material 5 with a Curie temperature of less than 400&deg;C, a magnetic material 6 with a Curie temperature of not less than 400&deg;C, and an elastomer 7, the high-frequency heating element can obtain excellent temperature-raising performance (temperature-rising speed and achieved temperature), restrain hardening of rubber under high-temperature environments, and realize excellent durability-reliability. And also, by mounting the high-frequency heating element 3 onto a heated-object placing dish, both delicacy and appropriate brown color can be attained, thus a cooking appliance for a high-frequency heating apparatus excellent in cooling performance can be provided. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a high-frequency heating element that generates heat by a high frequency used in a microwave oven and the like, a cooking utensil for a high-frequency heating device capable of scoring the surface of an object to be heated by high-frequency heating, and a high-frequency heating device using the same. It is.

  Conventionally, as this type of high-frequency heating element and cooking utensils for high-frequency heating equipment, a high-frequency heating element mainly composed of a magnetic material is provided on the bottom surface of a heated object placing plate on which an object to be heated is placed. (For example, refer to Patent Document 1).

  FIG. 4 is a perspective view of a heated object placing tray 31 provided with a conventional high-frequency heating element described in Patent Document 1. As shown in FIG. The high-frequency heating element is provided on the bottom surface (not shown) of the heated object placing tray 31.

  FIG. 5 is a partial cross-sectional view of a heated object placing tray 31 provided with a high-frequency heating element. As shown in FIG. 5, the high-frequency heating element 32 is provided on a painted metal base material 33 that constitutes the article to be heated 31. The high-frequency heating element 32 is composed of particles of a high-frequency absorption material mainly composed of a magnetic material with spherical particles and a Curie temperature of 200 to 300 ° C., and a rubber material. The particles of the magnetic material are uniformly in the rubber material. In a distributed state.

  The heated object placing tray 31 on which the food is placed is placed at a predetermined position of a high-frequency cooking device equipped with a magnetron (not shown) that generates a high frequency, and when grill cooking is started, the magnetron oscillates. The high-frequency heating element 32 provided on the heated object mounting tray 31 absorbs the high frequency and is converted into heat, and the heated object mounting tray 31 is heated. And the to-be-heated object which is contacting the heated to-be-heated object mounting tray 31 is heated, and a to-be-heated object becomes burnt with progress of cooking.

  In general, when performing grill cooking, when trying to achieve both the deliciousness of the cooked food to be heated and the suitable burnt, the heated object placing plate 31 is different depending on the type and amount of the heated object. It is necessary to raise the temperature to 150 to 300 ° C. in a short time.

Another material for the high-frequency heating element is a composition of magnetite and elastomer (see, for example, Patent Document 2).
JP 2007-225186 A JP 2007-45975

  However, since the conventional high-frequency heating element uses a magnetic material having a Curie temperature of 200 to 300 ° C., the magnetic material absorbs the high frequency to generate heat, and when the temperature rises near 200 ° C., the magnetic phase of the magnetic material As a result of the transition, magnetic loss, which is one of the magnetic characteristics, is reduced, the high-frequency absorption performance is reduced and the heating rate is slowed, and the high-frequency heating element is attached to the heated object mounting tray, so that the heated object There was a problem that thermal resistance of the mounting tray and heat loss due to heat dissipation occurred, the ultimate temperature of the high-frequency heating element was 250 ° C. or lower, and the temperature did not rise above that.

In addition, when this high-frequency heating element is used as a device for high-frequency heating equipment, if the temperature is raised to a temperature close to 200 ° C., the rate of temperature rise of the object to be heated becomes slow due to a decrease in the high-frequency absorption performance of the magnetic material. , It takes time to moderately burn the object to be heated, the cooking time becomes longer, the overheating state of the object to be heated due to the longer cooking time occurs, and the moisture content inside the object to be heated It had the problem that it decreased and taste was lost.

On the other hand, there is magnetite (Fe ₃ O ₄ ) as a material having a high Curie temperature. Magnetite's Curie temperature is as high as 580 ° C, and no magnetic phase transition occurs at 300 ° C. However, in the combination of magnetite and silicon rubber, the crosslinking reaction of silicon rubber occurs by magnetite in a high temperature environment, and the silicone rubber shrinks and cures. Occurs. As a result, the high-frequency heating element is peeled off from the object placing tray due to shrinkage and cracked due to curing, and the function as the high-frequency heating element is lost, and the durability and reliability as the high-frequency heating element are inferior. It had a problem.

  In addition, when a high-frequency heating element using magnetite as a magnetic material is bonded to a heated object mounting dish and used as a cooking utensil for a high-frequency heating device, cracking or peeling due to curing of the high-frequency heating element occurs. The high-frequency heating element drops off from the dish to be heated, the heat generation function is lost, and the high-frequency heating element cannot be used as a cooking utensil for high-frequency heating equipment. In addition, there is a possibility of ignition due to rubber combustion, and there is a possibility of burning when the user removes the high-frequency heating element that has dropped off, which is not preferable for safety.

  The present invention solves the above-mentioned conventional problems, and improves the temperature rise performance of the high-frequency heating element by using magnetic materials having different Curie temperatures for the high-frequency heating element, and raises the temperature to a higher temperature than before. High-frequency heating elements that can achieve excellent cooking performance in cooking of heated objects, prevent peeling and cracking, and ensure high durability, reliability, and safety, and use the same An object of the present invention is to provide a cooking utensil for a high-frequency heating apparatus.

  In order to solve the conventional problems, the high-frequency heating element of the present invention includes at least two kinds of magnetic materials having different Curie temperatures.

  As a result, the heated object mounting tray to which the high-frequency heating element is attached can increase the rate of temperature rise in a low temperature range of 200 ° C. or lower, and 200 ° C. or higher due to the presence of a magnetic material having a high Curie temperature. In the temperature range, it is possible to suppress a decrease in the heat generation performance of the entire high-frequency heating element, to achieve an excellent temperature rise performance, and to increase the ultimate temperature of the object to be heated. .

  The cooking device for a high-frequency heater according to the present invention is provided with the high-frequency heating element according to the present invention on a metal heated object mounting tray on which a coating layer containing an organic polymer is placed. This is a configuration.

  As a result, the high-frequency heating element always has a stable and high temperature raising performance, and the metal heated object mounting tray provided with the high-frequency heating element has excellent thermal conductivity. Since the generated heat can be efficiently transferred to the object tray, the object to be heated can be appropriately burned in a short time and the water inside the object to be heated can be reduced. Overheating is prevented, and the deliciousness of the object to be heated can be realized.

The high-frequency heating element of the present invention and the cooking utensil for a high-frequency heating apparatus using the same can realize superior temperature rise performance and high ultimate temperature by high frequency than before by coexisting magnetic materials having different Curie temperatures. it can.

  Further, by preventing the deterioration due to the reaction between the magnetic material and the organic polymer, peeling and cracking of the high-frequency heating element can be prevented, and excellent durability and reliability can be realized.

  Furthermore, since overheating of the object to be heated can be prevented, a new cooking method that achieves both deliciousness and moderate burn can be realized.

  In the first invention, since the high-frequency heating element includes at least two kinds of magnetic materials having different Curie temperatures, the rate of temperature rise in a low temperature region of 200 ° C. or less can be increased, If so, the heat generation performance of the magnetic material having a low Curie temperature is reduced, but since the high frequency heating element contains a magnetic material having a high Curie temperature, it is possible to suppress a decrease in the heat generation performance of the entire high frequency heating element, Excellent temperature rise performance can be realized even at a temperature of 200 ° C. or higher, and the ultimate temperature of the heated object mounting tray to which the high-frequency heating element is attached can be increased to 250 ° C. or higher. As a result, the object to be heated can be appropriately burnt in a short time, and overheating of the object to be heated leading to a decrease in moisture inside the object to be heated can be prevented, and the deliciousness of the object to be heated can be realized. it can.

  In addition to the effects of the first invention, the second invention comprises a composite of at least two magnetic materials having different Curie temperatures and at least one elastomer, in addition to the first invention. The structure of the high-frequency absorbing material particles dispersed in the elastomer can prevent the high-frequency heating element from dropping or breaking even when subjected to mechanical shock due to external force or dropping, or thermal shock due to repeated cold heat. it can.

  According to a third aspect of the present invention, in particular, in the first or second high-frequency heating element, by combining a magnetic material having a Curie temperature of particularly less than 400 ° C. and a Curie temperature of 400 ° C. or more, Can be raised to the required temperature in a short time.

  According to a fourth invention, in particular, in the magnetic material of the third invention, as a magnetic material having a Curie temperature of less than 400 ° C., at least one of Mn—Zn, Ni—Zn, and Mg—Ni ferrite, By using magnetite as the magnetic material at 400 ° C. or higher, the high-frequency heating element can be heated using the high magnetic loss of these galvanic magnetic materials, so that excellent temperature rise performance can be realized.

  In addition, Mn—Zn, Ni—Zn, and Mg—Ni ferrites, which are magnetic materials having a Curie temperature of less than 400 ° C., are chemically stable materials that do not promote the oxidation reaction of the elastomer, and are high frequency. Curing of the heating element can be prevented. On the other hand, magnetite, which is a magnetic material having a Curie temperature of 400 ° C. or higher, has a high magnetic loss and a high Curie temperature, so that the heating rate and ultimate temperature of the high-frequency heating element can be increased. There is. However, since the high-frequency heating element contains a magnetic material having a Curie temperature of less than 400 ° C., the content of magnetite can be reduced, so that the oxidation reaction with the elastomer becomes slow and the curing of the elastomer is suppressed. be able to. Therefore, by combining these magnetic materials having different Curie temperatures, it is possible to achieve excellent temperature rise performance, and by suppressing the curing reaction of the elastomer, high-frequency heat generated due to the curing of the elastomer. Since cracking and peeling of the body can be prevented, a high-frequency heating element having excellent cooking performance and high reliability, durability, and safety can be obtained.

  In the fifth invention, in particular, in any one of the second to fourth inventions, by using silicon rubber or fluorine rubber as the elastomer, they have excellent heat resistance and chemical resistance, A high-frequency heating element with high durability and reliability can be realized.

  According to a sixth invention, in particular, in any one of the first to fifth inventions, the total content of at least two magnetic materials having different Curie temperatures is set to 20 to 60% by volume, thereby absorbing high frequency. The heat generation performance, the mechanical strength of the high-frequency heating element, and the adhesion to the object to be heated can be improved.

  According to a seventh invention, in particular, in any one of the third and fourth inventions, by setting the content of the magnetic material having a Curie temperature of 400 or more to 20 to 50% by volume with respect to the total amount of the magnetic material, The effect of suppressing the oxidation reaction with the elastomer can be increased, and the cracking and peeling of the high-frequency heating element caused by the curing of the elastomer can be greatly improved, and the reliability, durability, and safety can be further increased. .

  According to an eighth aspect of the present invention, as the cooking utensil for the high-frequency heating device, the object to be heated of the metal object-to-be-heated dish on which the coating layer containing the organic polymer is placed is not placed. By providing the high-frequency heating element of any one of the first to seventh inventions on a part of the surface, it is possible to always achieve a stable and high temperature raising performance.

  Moreover, since the metal heated object mounting tray provided with the high frequency heating element has excellent thermal conductivity, the heat generated by the high frequency heating element can be efficiently transmitted to the heated object mounting dish. In addition to being able to burn the object to be heated in a short time, overheating of the object to be heated can be prevented, and moisture inside the object to be heated can be maintained, and both deliciousness and moderate burn can be achieved. A new cooking method can be realized.

In the ninth aspect of the invention, in particular, in the high-frequency heating element of the eighth invention, the area of the high-frequency heating element provided on the metal heated object mounting tray is set to 0.1 m ² or less so that predetermined power consumption is achieved. The heated object placing tray and the heated object placed thereon can be heated to a predetermined temperature in a short time at a high frequency, and cooking time can be shortened and energy can be saved.

  In the tenth aspect of the invention, in particular, the heat transfer to the dish to be heated due to the increase of the film thickness by setting the film thickness of the high-frequency heating element of the eighth or ninth invention to 0.5 to 2 mm. And a decrease in the heating rate due to an increase in the heat capacity of the high-frequency heating element itself, and a decrease in the high-frequency absorption performance of the high-frequency heating element due to the thin film thickness can be suppressed. The heat generated by the heating element absorbing the high frequency can be efficiently transmitted to the object to be heated and the object to be heated, and cooking time can be shortened and energy can be saved.

  In an eleventh aspect of the invention, a heating chamber for storing an object to be heated, a heater provided at an upper portion of the heating chamber, a high frequency is generated and a high frequency is applied to an object to be heated stored in the heating chamber from the bottom of the heating chamber. A high-frequency generating means for high-frequency heating the object to be heated, and a metal object-mounted tray on which the object to be heated is detachably attached to the heating chamber. A high-frequency cooking appliance provided with a high-frequency heating element made of a composite of at least two kinds of magnetic materials having different Curie temperatures to be heated and at least one kind of elastomer is provided on a part of the lower surface of the dish.

As a result, the rate of temperature rise in a low temperature region of 200 ° C. or lower can be increased. Further, when the temperature is close to 200 ° C., the heat generation performance of a magnetic material having a low Curie temperature is reduced. Because it contains a magnetic material with a high temperature, it is possible to increase the temperature reached to the object to be heated to 250 ° C. or higher, and as a result, the object to be heated can be appropriately burnt in a short time. The overheating of the object to be heated leading to a decrease in the moisture inside the object to be heated is prevented, and the object to be heated can be cooked deliciously.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the present embodiment. In addition, a configuration unique to each embodiment can be combined as appropriate.

(Embodiment 1)
FIG. 1 shows a cross-sectional view of a cooking utensil for a high-frequency heating device provided with a high-frequency heating element according to the first embodiment of the present invention.

  In addition, the form of FIG. 5 described by background art is applied to the to-be-heated material mounting dish used as a cooking appliance for this invention high frequency heating equipment.

  In FIG. 1, a cooking utensil 1 for a high-frequency heating device includes a metal heated object placing tray 2 on which a coating layer containing an organic polymer is formed, and a part of the lower surface of the heated object placing dish 2. The high-frequency heating element 3 is provided. Moreover, in order to attach the to-be-heated object mounting dish 2 to the predetermined position in the warehouse of high frequency heating apparatuses, such as a microwave oven, in the both ends of the to-be-heated object mounting dish 2, the fixing member 4 is attached. ing. The fixing member 4 functions not only as a positioning function of the heated object placing tray 2 but also as a handle when carrying and taking out, and the metal heated object placing dish 2 is placed in the high frequency heating apparatus. And having an insulating function for preventing sparks when high-frequency power is supplied.

  FIG. 2 is a schematic diagram showing the structure of the high-frequency heating element 3.

  In FIG. 2, the high-frequency heating element 3 includes a magnetic material 5 having a Curie temperature of less than 400 ° C., a magnetic material 6 having a Curie temperature of 400 ° C. or higher, and an elastomer 7. 7 is distributed in the structure.

  Next, an embodiment of a method for producing the high frequency heating element 3 of the present invention will be described.

  First, using a kneading apparatus such as an open roll or a kneader, a magnetic material 5 having a Curie temperature of less than 400 ° C., a magnetic material 6 having a Curie temperature of 400 ° C. or more blended in a predetermined blending amount, and an elastomer 7 are used. Kneading until the particles of the magnetic material 5 having a Curie temperature of less than 400 ° C. and the magnetic material 6 having a Curie temperature of 400 ° C. or more are uniformly dispersed in the elastomer 7, and then adding a cross-linking agent as necessary. Knead again.

  Next, a necessary amount of the kneaded material lump or the sheet formed by an open roll is collected and placed on the surface of the object to be heated 2 on which the object to be heated is not placed. And pressure bonding and primary vulcanization. Thereafter, by performing heat treatment such as secondary vulcanization as necessary, the cooking utensil 1 for the high-frequency heating device of the present invention having the configuration in which the high-frequency heating element 3 is formed on the article to be heated 2 is obtained.

  During kneading, a heat-resistant agent for imparting further heat resistance of the high-frequency heating element 3, an anti-aging agent, an oil and fat agent for imparting flexibility, and the like may be added as necessary.

Moreover, in order to improve the adhesiveness between the high-frequency heating element 3 and the heated object placing tray 2, the bonding surface of the high-frequency heating element 3 or the surface on which the high-frequency heating element 3 of the heated object placing dish 2 is provided. In addition, a primer having an adhesive function may be applied, and the heated object mounting tray 2 and the high-frequency heating element 3 may be bonded via the primer. In addition, the magnetic material 5 having a Curie temperature of less than 400 ° C. An adhesive may be added when the magnetic material 6 having a Curie temperature of 400 ° C. or higher and the elastomer 7 are kneaded.

  FIG. 3 is a cross-sectional view of a high-frequency cooking device on which the cooking utensil 1 for high-frequency heating equipment according to the present invention is mounted.

  In FIG. 3, the heating chamber 9 is a metal boundary portion made of a metal material. The right wall surface 10, the left wall surface 11, the back wall surface 12, the upper wall surface 13, the bottom wall surface 14, and an object to be heated are placed in the heating chamber 9. An open / close door (not shown) that is an open / close wall surface to be taken in and out is formed into a substantially rectangular parallelepiped shape. It forms so that the supplied high frequency may be confined substantially inside. The bottom wall surface 14 is provided with a narrowed section 15 having a substantially rectangular cross section, and a high frequency excitation section 16 for supplying power into the heating chamber 9 is disposed at a substantially central portion of the narrowed section 15.

  The magnetron 17 that is a high frequency generating means generates a high frequency to be fed to the heating chamber 9, and a waveguide is provided between the magnetron 17 and the excitation unit 16 in order to guide the high frequency generated from the magnetron 17 to the excitation unit 16. 18 is provided. An antenna 19 extending in the waveguide 18 and coupled to the high frequency transmitted through the waveguide 18 is provided in the excitation unit 16, and one end of the antenna 19 is used as a radiation antenna having a waveguide type directivity. The radio wave radiation means 20 is connected.

  The other end of the antenna 19 is assembled by inserting and assembling an output shaft of a motor 21 that is a driving means for rotating the radio wave radiating means 20. The radio wave radiating means 20 is driven to rotate by driving the motor 21 so that the fan-shaped upper surface is substantially parallel to the bottom surface of the aperture 15.

  In addition, a sealing means 22 made of a radio wave transmitting material, for example, a glass-based or ceramic-based material is provided at the opening of the aperture 15. This sealing means 22 partitions the inside of the heating chamber 9 up and down, and transmits the high frequency radiated from the antenna 19 to the object to be heated.

  In addition, a heater 23 is provided in the upper part of the heating chamber 9, and a convection heater unit (not shown) is provided in the back of the back wall surface 12, and functions of high-frequency cooking, grill cooking, and oven cooking of the heated object. It has the composition which has.

  The cooking utensil 1 for a high-frequency heating device is inserted and attached into the heating chamber 9 along a rail portion 24 which is a locking means provided on the right wall surface 10 and the left wall surface 11 of the heating chamber 9.

  The heating chamber 9 is provided with a thermistor 25 that detects the temperature in the heating chamber 9 and an infrared sensor 26 that detects the temperature of the object to be heated, the cooking utensil 1 for high-frequency heating equipment, and the like.

  Next, the operation and action of the cooking utensil 1 for a high-frequency heating device of the present invention will be described using the high-frequency heating cooker having the above configuration.

  When a predetermined instruction operation is performed in a state where the cooking utensil 1 for a high-frequency heating device in which an object to be heated is placed in the heating chamber 9 is locked to the rail portion 24 and the open / close door is closed, the magnetron 17 is controlled by the control means 27. Operates to generate high frequency. The generated high frequency passes through the waveguide 18 and the excitation unit 16, passes through the sealing means 22 made of ceramic or the like from the radio wave emission means 20, and is fed into the heating chamber 9 from below. The high frequency fed into the heating chamber 9 is absorbed by the high frequency heating element 3 constituting the cooking utensil 1 for high frequency heating equipment and converted into heat. The heat is transmitted to the heated object placing tray 2 constituting the cooking utensil 1 for high-frequency heating equipment, and the heated object in contact with the heated object placing dish 2 is heated.

  In general, when grill cooking is performed, if an attempt is made to achieve both the deliciousness of the cooked food to be heated and a suitable burnt, the heated object placing plate is 150 to 300 depending on the type and amount of the heated object. It is necessary to raise the temperature to a temperature of ° C in a very short time.

  Conventionally, a Mn—Zn-based magnetic material is used as a high-frequency absorbing material for a high-frequency heating element. The Curie temperature of this magnetic material varies depending on the composition, but is 200 to 300 ° C. The heat generation mechanism of the magnetic material is mainly due to the magnetic loss of the material. When the high frequency is absorbed and heat-converted and reaches the Curie temperature (near), the magnetic loss is reduced by the magnetic phase transition, and the high frequency absorption performance is improved. By decreasing, the heating rate above the Curie temperature is remarkably decreased. As a result, it takes time to moderately burn the object to be heated, the cooking time becomes longer, the overheating state of the object to be heated occurs, the amount of moisture inside the object to be heated decreases, and the taste is delicious. Will be lost.

  On the other hand, a magnetite having a Curie temperature of 500 ° C. or higher has a fast rate of temperature rise because no magnetic phase transition occurs at 300 ° C. However, depending on the type and chemical composition of the elastomer, magnetite accelerates the crosslinking reaction of elastomers such as silicon rubber, and the high-frequency heating element is peeled off and cracks due to the shrinkage and curing of the elastomer.

  The high-frequency heating element 3 of the present invention uses a magnetic material 5 having a Curie temperature of less than 400 ° C. and a magnetic material 6 having a Curie temperature of 400 ° C. or higher. More specifically, examples of the magnetic material 5 having a Curie temperature of less than 400 ° C. include at least one of Mn—Zn, Ni—Zn, and Mg—Ni ferrite, and a magnetic material having a Curie temperature of 400 ° C. or higher. A magnetite is mentioned as 6.

  When only the magnetite having a Curie temperature of 400 ° C. or higher is used as the magnetic material of the high-frequency heating element 3 of the present invention, there is an adverse effect due to the curing of the elastomer 7, but the present invention is not limited to magnetite alone and has a Curie temperature of 400. A magnetic material 5 of less than or equal to ° C. is used in combination. In particular, Mn—Zn-based, Ni—Zn-based, and Mg—Ni-based ferrites having a Curie temperature of less than 400 ° C. are materials that are chemically stable and do not promote the oxidation reaction of the elastomer 7, and do not cure the elastomer 7. It is.

  Therefore, by using at least one of Mn—Zn, Ni—Zn, and Mg—Ni ferrite having a Curie temperature of less than 400 ° C. for the high-frequency heating element 3, the content of magnetite having a Curie temperature of 400 ° C. or more is reduced. can do. By reducing the content of magnetite, the oxidation reaction with the elastomer 7 becomes slow, and the progress of curing of the elastomer 7 is suppressed as compared with magnetite alone. As a result, cracks and peeling of the high-frequency heating element that have conventionally occurred due to the curing of the elastomer that has occurred in an extremely short time are remarkably improved, and stable heat generation performance can be realized over a long period of time.

  In addition, cracking and peeling due to the hardening of the high-frequency heating element causes the high-frequency heating element to fall off the dish to be heated and lose its heat generation function, making it not usable as a cooking utensil for high-frequency heating equipment. The high-frequency heating element itself that has fallen is heated to a high temperature of 300 ° C. or higher due to the high frequency, and it is possible to avoid the possibility of ignition due to rubber combustion and the possibility of burns when the user removes the high-frequency heating element that has dropped off. High durability, reliability, and safety can be realized.

Furthermore, the high-frequency heating element 3 of the present invention can improve high-frequency heat generation performance. As described above, the high frequency heating element 3 includes the magnetic material 5 having a Curie temperature of less than 400 ° C. and the magnetic material 6 having a Curie temperature of 400 ° C. or higher. In the temperature range of 200 ° C. or higher, the magnetic material 5 having a Curie temperature of 300 ° C. or lower has a small magnetic loss and the heat generation performance is reduced. However, the magnetic material 6 having a high Curie temperature of 400 ° C. or higher does not have a reduced magnetic loss. A decrease in temperature rise performance as the high-frequency heating element 3 is suppressed.

  With this action, the high-frequency heating element 3 can be heated to a temperature of 200 ° C. or higher in a short time, and the ultimate temperature of the heated object mounting tray 2 to which the high-frequency heating element 3 is attached cannot be obtained conventionally. 250 ° C. or higher can be realized. As a result, the object to be heated can be appropriately burnt in a short time, and overheating of the object to be heated leading to a decrease in moisture inside the object to be heated can be prevented, and the deliciousness of the object to be heated can be realized. it can.

  Although the ultimate temperature of the high-frequency heating element 3 including the heated object placing tray 2 depends on the Curie temperature of the magnetic material due to the high-frequency energy, the high-frequency heating element 3 according to the present invention has high frequency energy input power, high frequency When a magnetic material having a Curie temperature of around 200 ° C. is used due to the heat capacity of the heating element 3 and the object placing tray 2 and heat loss due to heat dissipation after the temperature rise, the ultimate temperature is almost the same, The magnetic material having a Curie temperature higher than that reaches the Curie temperature, and even if it is a magnetic material having a Curie temperature of 350 to 400 ° C., the heated object mounting plate to which the high-frequency heating element 3 of the present invention is attached. 2 (the cooking utensil 1 for high-frequency heating equipment) reaches 250 ° C. or less. In other words, a magnetic material having a Curie temperature of 400 ° C. or higher is required to make the ultimate temperature 250 ° C. or higher.

  When the total content of at least two kinds of magnetic materials having different Curie temperatures used for the high-frequency heating element 3 is 20% by volume or less, the high-frequency absorption performance decreases, and a satisfactory temperature rising performance as the high-frequency heating element 3 is obtained. Further, if the volume is 60% by volume or more, the composite with the elastomer 7 becomes hard, the flow of the composite is poor during hot pressing, and the high-frequency heating element 3 having a uniform film thickness cannot be obtained. Since the formed film is hardened, the thermal shock resistance and the mechanical shock resistance are lowered. Therefore, when the fall or the cold heat is repeated, the high-frequency heating element 3 may be damaged. Therefore, in order to ensure excellent temperature rise performance, durability, and reliability, it is desirable that the total content of at least two magnetic materials having different Curie temperatures is in the range of 20 to 60%.

  Further, when magnetite is used as the magnetic material 6 having a Curie temperature of 400 ° C. or higher, the amount of the magnetic material 6 having a Curie temperature of 400 ° C. or higher is larger than that of the magnetic material 5 having a Curie temperature of less than 400 ° C. The high-frequency heating element 3 itself is markedly cured by the oxidation reaction, causing cracks and peeling. On the other hand, when the Curie temperature is lower than that of the magnetic material 6 lower than 400 ° C., the temperature raising performance of the high-frequency heating element 3 is lowered, the temperature raising rate is lowered, and the ultimate temperature is 250 ° C. or lower.

  In order to obtain an ultimate temperature of 250 ° C. or higher, the amount of magnetic material 6 (magnetite) having a Curie temperature of 400 ° C. or higher needs to be at least 20% by volume with respect to the total amount of magnetic material used for the high-frequency heating element 3. Become. Therefore, the content of the magnetic material 6 having a Curie temperature of 400 ° C. or higher is desirably 20 to 50% by volume with respect to the total amount of the magnetic material, and this composition increases the effect of suppressing the oxidation reaction with the elastomer 7. In addition, cracks and peeling of the high-frequency heating element caused by the curing of the elastomer 7 are greatly improved, and reliability, durability, and safety can be further increased.

  In addition, the high-frequency heating element 3 provided on the heated object placing tray 2 is preferably a composite of at least two kinds of magnetic materials having different Curie temperatures and at least one kind of elastomer 7. With this configuration, the elastomer 7 can protect the particles of the magnetic material having different Curie temperatures and can realize strong adhesion to the heated object placing tray 2, so that mechanical shock or cold heat caused by external force or dropping can be realized. It is possible to strengthen against the thermal shock caused by the repetition of the above, and it is possible to prevent the high-frequency heating element 3 from dropping or breaking.

  In particular, the material of elastomer 7 used in the present invention is heat resistance in a temperature environment of 300 ° C. as a cooking utensil 1 for high-frequency heating equipment, chemical resistance such as seasonings and water vapor, mechanical shock resistance, and thermal shock resistance. It is required to have excellent properties. Examples of materials that satisfy these required specifications include silicon rubber and fluororubber, which are optimal as the elastomer 7 of the high-frequency heating element 3.

  Moreover, the cooking utensil 1 for the high-frequency heating device of the present invention has the heat generated by the high-frequency heating element 3 because the heated object mounting tray 2 has excellent thermal conductivity. The heat can be efficiently transmitted to the article to be heated placing tray 2. Therefore, the heated object placing tray 2 can be heated to a predetermined cooking temperature in a short time, and an appropriate burn can be applied to the heated object in a short time.

  Moreover, since the cooking utensil 1 for high-frequency heating equipment can prevent overheating of the heated object, it can retain the moisture inside the heated object necessary for deliciousness, and is a new cooking that balances both deliciousness and moderate burns. A method can be realized.

  Moreover, since the high-frequency heating element 3 can achieve a stable temperature rise performance over a long period of time, the cooking utensil 1 for a high-frequency heating device having excellent durability and reliability can be provided.

When the magnetron 17 is operated with a power consumption of 700 to 1000 W, if the area of the high-frequency heating element 3 provided in the metal heated object mounting tray 2 is 0.1 m ² or more, the heated object mounting dish 2 Since the heat capacity of the cooking utensil 1 itself for the high frequency heating device increases and the heat dissipation loss increases due to the expansion of the heat dissipation area due to the increase in the surface area, The speed becomes slow, and the optimum burnt and deliciousness of the heated object cannot be obtained.

Therefore, in order to obtain optimum burnt and deliciousness, it is desirable that the area of the high-frequency heating element 3 is 0.1 m ² or less. Moreover, since the to-be-heated material mounting tray 2 and the to-be-heated material mounted on it can be heated up to predetermined temperature in a short time by this, cooking time can be shortened and energy saving can be achieved.

  If the film thickness of the high-frequency heating element 3 is 2 mm or more, the heat capacity of the high-frequency heating element 3 is increased, the heating rate of the high-frequency heating element 3 is decreased, and the thermal resistance of the high-frequency heating element 3 is increased. Since the heat dissipation loss from the surface of the high-frequency heating element 3 is increased, the heat transfer due to heat conduction to the heated object placing tray 2 is reduced, and a fast temperature increase rate of the heated object placing plate 2 cannot be obtained. . Further, the cost increases due to the thick film thickness.

  On the other hand, if the film thickness of the high-frequency thermal heating element 3 is 0.5 mm or less, the amount of the magnetite particles 5 on which the coating layer is formed decreases, the high-frequency absorption efficiency decreases, and a high temperature rise rate cannot be obtained. .

  Therefore, in order to efficiently transmit the heat generated by the high-frequency heating element 3 by absorbing the high frequency to the heated object placing tray 2 and the heated object, the thickness of the high-frequency heating element 3 is in the range of 0.5 to 2 mm. Is desirable. Thus, the heated object placing tray 2 and the heated object placed thereon can be heated to a predetermined temperature in a short time, and cooking time can be shortened and energy can be saved.

As described above, since the high-frequency heating element of the present invention has excellent temperature rise performance, it can be applied not only as a heating element for cooking appliances but also for use in industrial dryers and heating machines. Since it has excellent absorption performance, it can be applied as a radio wave sealing device with a cooling device.

Sectional drawing of the cooking utensil for high frequency heating appliances provided with the high frequency heating element in Embodiment 1 of this invention Schematic diagram showing the structure of the high-frequency heating element according to Embodiment 1 of the present invention. Sectional drawing of the high frequency heating cooking appliance with which the cooking appliance for high frequency heating equipment of this invention is mounted The perspective view of the to-be-heated material mounting tray provided with the conventional high frequency heating element Partial sectional view of a conventional dish to be heated

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cooking utensil for high frequency heating equipment 2 To-be-heated object mounting dish 3 High frequency heating element 5 Magnetic material with Curie temperature of less than 400 degreeC 6 Magnetic material with Curie temperature of 400 or more 7 Elastomer

Claims (11)

A high-frequency heating element comprising at least two magnetic materials having different Curie temperatures. The high-frequency heating element according to claim 1, comprising a composite of at least two magnetic materials having different Curie temperatures and at least one elastomer. The high-frequency heating element according to claim 1 or 2, wherein at least two kinds of magnetic materials having different Curie temperatures have a Curie temperature of less than 400 ° C and a Curie temperature of 400 ° C or more. The high frequency according to claim 3, wherein at least one of Mn-Zn, Ni-Zn, and Mg-Ni ferrite is used as the magnetic material having a Curie temperature of less than 400 ° C, and magnetite is used as the magnetic material having a Curie temperature of 400 ° C or higher. Heating element. The high-frequency heating element according to any one of claims 1 to 4, wherein the elastomer includes silicon rubber or fluorine rubber. The high-frequency heating element according to any one of claims 1 to 5, wherein the total content of at least two magnetic materials having different Curie temperatures is 20 to 60% by volume. The high frequency heating element according to claim 3 or 4, wherein the content of the magnetic material having a Curie temperature of 400 or more is 20 to 50% by volume with respect to the total amount of the magnetic material. On a part of the surface on which the object to be heated of the object to be heated is not placed and a metal object to be heated on which the coating layer containing an organic polymer is placed. A cooking utensil for a high-frequency overheating device comprising the high-frequency heating element according to any one of claims 1 to 7. The cooking utensil for a high-frequency heating device according to claim 8, wherein an area of the high-frequency heating element provided on the metal heated object placing tray is 0.1 m ² or less. The cooking utensil for a high-frequency heating device according to claim 8 or 9, wherein the film thickness of the high-frequency heating element provided on the metal heated object mounting tray is 0.5 to 2 mm. A heating chamber for storing an object to be heated, a heater provided at an upper portion of the heating chamber, and a high frequency is generated from the bottom of the heating chamber to radiate the high frequency to the object to be heated and stored in the heating chamber. A high-frequency generating means for high-frequency heating an object; and a metal heated object mounting tray on which a heated object is detachably attached to the heating chamber, and a part of a lower surface of the heated object mounting dish A high-frequency cooking appliance provided with a high-frequency heating element made of a composite of at least two kinds of magnetic materials having different Curie temperatures to be heated and at least one kind of elastomer.