JP4961382B2 - rice cooker - Google Patents

Description

  The present invention relates to a rice cooker that cooks rice by heating an inner pot by electromagnetic induction heating.

  The electromagnetic induction heating type jar rice cooker uses a magnetic material that is induction-heated by an induction heating coil on the outer surface as the material of the inner pot, and heat from the magnetic material generated by induction heating on the inner surface. It is common to use materials with good thermal conductivity so that they can be uniformly transmitted to rice. As shown in Patent Document 1, the outer surface is a stainless steel plate and the inner surface is an aluminum plate. Many clad materials are drawn into an inner pot shape.

  Moreover, as shown in Patent Document 2, a dish-shaped stainless steel plate or the like, which is a magnetic metal material, is laid on the bottom surface of a receiving mold having an inner pot shape, and molten aluminum, which is a nonmagnetic metal material, is injected thereon, There is also a type in which an inner pan is molded by pressing from above with high pressure.

  Furthermore, in order to increase the efficiency of induction heating, as shown in Patent Document 3, iron having the best electromagnetic induction heating efficiency is sprayed on the outer bottom surface of the inner pot in which an aluminum plate is drawn, and further, iron spraying is performed. In order to prevent rusting of the surface, there is also one in which aluminum is sprayed so as to cover the iron sprayed surface.

JP-A-5-199934 JP-A-8-24123 JP 2003-290022 A

  In the above-mentioned electromagnetic induction heating type jar rice cooker, it is ideal to use iron with the best heat generation efficiency in the heating part of the inner pot, but the inner pot is always used around water, There is a problem, and as described above, a nonmagnetic material is used for the inner surface and a magnetic material is used for the outer surface as shown in Patent Documents 1, 2, 3, and the like.

  Among them, what is shown in Patent Document 1, which is currently mainstream, is only drawn into an inner pan shape using a clad material having a stainless steel outer surface and an aluminum inner surface. Although there is an advantage that the processing cost of the pan is low, the heat generation efficiency of the stainless steel plate, which is a magnetic material, is about 78%, which is lower than that of about 84% of iron, which is a ferromagnetic material.

  In addition, in the actual production of the one shown in Patent Document 2, since the magnetic metal material needs to have a strength that can withstand high-pressure melt forging, iron that is a strong magnetic material cannot be used, and is limited to a stainless steel plate. For this reason, there is a drawback that the heat generation efficiency is poor as in the above-mentioned Patent Document 1.

  Further, depending on the shape of the inner pot, there is a concern that the dish-shaped stainless steel plate may be peeled off from the aluminum material, and further, since it is high-pressure melt forging, there is a disadvantage that the production cost is great and cannot be provided to consumers at low cost.

  Furthermore, in the one shown in Patent Document 3, innumerable rough irregularities are formed on the sprayed surface after iron spraying, so there is a risk of damaging the sink or the like as it is. After spraying, it is necessary to polish the sprayed surface, and there is a drawback that the processing cost is increased compared to the clad material.

  In addition, it is difficult to manage the film thickness by spraying, and if weight management of spraying is performed instead of film thickness management, a weight variation of about 10% of the target value occurs, and the heat generation amount of electromagnetic induction heating, that is, product consumption. An error is likely to occur in the power.

  Furthermore, in recent years, in order to improve the uniform heating property of rice, an induction heating coil may be provided on the side surface portion of the inner pot, and if the thermal spraying is performed to the side surface of the inner pot, the processing cost is further increased.

  In order to solve such a conventional problem, in claim 1 of the present invention, a main body, a protective frame constituting the inner wall of the main body, an inner pot detachably accommodated in the protective frame, and the protective frame In the rice cooker provided with heating means arranged on the outside for inductively heating the inner pot, and a lid for closing the upper surface opening of the main body and the inner pot, the inner pot has an aluminum plate on the inner surface and an iron plate on the outer surface. It is made of aluminized steel sheet that is aluminized, provided with an inclined part on the end face of the upper end of the inner pot, a fluororesin layer on the inner side of the inner pot, and a rust preventive layer on the outer side and the end face of the upper end. Is given.

  According to the first aspect of the present invention, since the inner plate is made of a clad material of an inner side aluminum plate and an outer side aluminum plated steel plate, the aluminum plated steel plate is a ferromagnetic material, so that the heating efficiency of induction heating is increased. Therefore, the electromagnetic induction heating performance can be improved and the energy saving property can be improved.

  Further, the processing cost is equivalent to that of the conventional aluminum plate and stainless steel clad material, and it can be manufactured at low cost because an expensive manufacturing method is not employed.

  In addition, by using the clad material as described above, variation in weight can be suppressed as compared with iron spraying, and the amount of heat generated by electromagnetic induction heating, that is, power consumption error can be eliminated, and power consumption can be easily managed. is there.

  In addition, the inner pan is formed into a shape of an inner pan by press drawing of a clad material made of an aluminum plate on the inner surface and an aluminum-plated steel plate on the outer side, and then the end surface of the upper end of the inner pan is formed by press punching In the case of forming into a shape, a cross section of aluminum, iron plate, and aluminum plating is exposed to the end face of the upper end portion of the inner pot by the press punching process, and there is a problem that rust occurs due to the cross section exposure of the iron plate. The end face of the upper end is provided with an inclined part in the exposed part of the iron plate by press crushing, etc., and the rust-prevention coating is applied after reducing the exposed part of the iron plate, so that the rust problem can be solved, and the aluminum plate and the aluminized steel plate are clad With this material, it is possible to provide a highly efficient inner pot.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a longitudinal sectional view of the entire jar rice cooker according to the present invention. 2 is a longitudinal sectional view of the upper end of the inner pot of the rice cooker, (a) is a longitudinal sectional view of the vicinity of the upper end of the inner pot, and (b) is a fluororesin coating on the inner surface for explanation from the previous figure (a). The longitudinal cross-sectional view except the antirust coating of an outer surface, (c) is a longitudinal cross-sectional view which shows the state before giving the process of the inclination part of (b).

  In the figure, the main body 1 of the jar rice cooker is provided with a protective frame 10 whose upper surface is opened inside, and an inner pot 3 is detachably accommodated in the protective frame 10.

  Heating means 11 including a bottom surface heating coil for induction heating the bottom surface portion of the inner pot 3 and a side surface heating coil for induction heating the side surface portion is provided on the outer bottom surface portion and the outer side surface portion of the protective frame 10.

  In addition, a lid 2 that covers the upper opening is attached to the upper surface opening of the main body 1 so as to be openable and closable. By opening the lid 2, the inner pot 3 can be stored in the main body 1.

  The inner pot 3 has a bottomed cylindrical shape, and the inner pot upper end portion 4 is bent substantially horizontally so that it can be easily attached and detached from the main body 1.

  Hereinafter, the details of the inner pot 3 will be described. The inner pot 3 is made of a plate material in which the inner side surface is an aluminum plate and the outer side surface is an aluminum-plated steel plate 6, and these are clad (rolled). Furthermore, the aluminum plated steel plate 6 is composed of an iron plate 6a and an aluminum plating 6b applied to the surface of the iron plate 6a. The aluminum plating 6b has a film thickness of about 10 to 30 μm and is formed on the outer surface of the inner pot 3. The iron plate 6a is prevented from being rusted due to water intrusion.

  The inner pot 3 is formed into a circular shape by press punching so that the clad bonded plate material is integrally formed into the shape of the inner pot 3 by press drawing and the upper end portion 4 of the inner pot has a desired outer diameter. As shown in FIG. 2C, the punching process exposes the cross sections of the aluminum plate 5, the iron plate 6a, and the aluminum plating 6b. For this reason, the exposed portion of the end surface of the iron plate 6a is rusted as it is, but this end surface is pressed into the exposed portion of the iron plate 6a as shown in FIG. An inner pan 3 that does not have to worry about rusting by providing an inclined portion 7 that is obliquely upward, minimizing the exposed portion of the iron plate 6a, and applying a heat-resistant rust prevention layer 9 as shown in FIG. 2 (a). Can be configured.

  In addition, the fluororesin layer 8 is given to the whole inner surface of the inner pot 3, and the peelability of rice is improved.

  With the above configuration, in the inner pot 3, the ferromagnetic iron plate 6a efficiently attracts a high-frequency magnetic field by electromagnetic induction heating by the heating means 11 and changes it to heat, and the film thickness of the aluminum plating 6b through which the magnetic flux passes is changed to 10 at this time. Since it is as thin as ˜30 μm, it becomes a target for electromagnetic induction heating and increases the electromagnetic induction heat generation efficiency of the inner pot 3.

  In general, an inner pot composed of a stainless steel plate and an aluminum plate has an electromagnetic induction heating efficiency of about 78%, whereas the aluminum-plated steel plate 6 according to the present invention has an efficiency of about 84%. Heat is transmitted to the entire inner pot 3 by the aluminum plate 5 having high thermal conductivity, and heats the rice deliciously.

  As described above, the present invention comprises an inner plate of an inner pot made of an aluminum plate and an outer surface made of an aluminum-plated steel plate plated with iron on an iron plate, provided with an inclined portion on the end surface of the upper end portion of the inner pot, Since the inner surface of the inner pot is coated with a fluororesin layer and the outer surface and the end face of the upper end are heat-resistant and rust-proof, the inclined part at the upper end of the inner pot has minimal exposure of the iron part of the end surface of the aluminized steel sheet. Thus, energy saving can be improved, and the inner pot can be made inexpensive and does not rust.

  In the present invention, the aluminum plated surface of the aluminum plated steel plate has been described with the configuration only on the outside of the inner pan. However, the aluminum plated steel plate in which both the outer surface of the inner pan and the clad joint surface with aluminum are plated with aluminum. Even if aluminum is joined, the effect is not changed and this configuration may be used.

It is sectional drawing of the whole rice cooker which concerns on this invention. It is a vertical cross-sectional view of the upper end portion of the inner pot of the rice cooker, (a) is a vertical cross-sectional view of the vicinity of the upper end portion of the inner pot, (b) is a fluororesin coating of the inner surface for the purpose of explanation from the previous figure (a), (C) is a longitudinal sectional view showing a state before processing the inclined portion of (b).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main body 2 Lid 3 Inner pan 4 Inner pan upper end part 5 Aluminum plate 6 Aluminum plating steel plate 6a Iron plate 6b Aluminum plating 7 Inclined part 8 Fluorine resin layer 9 Rust prevention layer

Claims (1)

  A main body, a protective frame constituting an inner wall of the main body, an inner pot detachably accommodated in the protective frame, a heating means disposed on the outer side of the protective frame for inductively heating the inner pot, and the main body And a rice cooker provided with a lid for closing the upper surface opening of the inner pot, the inner pot is composed of an aluminum plate on the inner side and an aluminum plate on the outer side with an aluminum plate, and the upper end of the inner pot. The rice cooker is characterized in that an inclined portion is provided on the end surface of the inner pot, a fluororesin layer is applied to the inner surface of the inner pot, and a rust preventive layer is applied to the outer surface and the end surface of the upper end portion.

Images