JPH10165297A - Instrument for electromagnetic cooking and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an instrument for electromagnetic cooling which is light in weight, reduced in cost and improved in heat efficiency, and production thereof. SOLUTION: An opening part is formed on the bottom of aluminium main body 1 of the instrument, a heating body 2 to heat by electromagnetic induction is arranged while closing the opening part, and the main body 1 of instrument and the heating body 2 are bonded on their boundary parts. Besides, a through hole 12 is formed on an aluminum panel 11 through in the thicknesswise direction and after a panel 21 for the heating body is fitted to the through hole 12, a bonding member 3 is produced by bonding the aluminium panel 11 and the panel 21 for the heating body. Then, the bonding member 3 is formed in the shape of the instrument so that the panel 21 for the heating body can be positioned on the bottom.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic cooking utensil such as a pot, a frying pan, a rice cooker and the like, which is heated by electromagnetic induction, and a method of manufacturing the same.

[0002] In this specification, the term aluminum is used to include its alloys.

[0003]

2. Description of the Related Art Since the above-mentioned electromagnetic cooking utensils need to generate heat by electromagnetic induction, it is necessary to employ a magnetic material as a material constituting the utensils. On the other hand, since the magnetic material is heavy and expensive, if the whole object is made of a magnetic material, it becomes too heavy, which makes handling inconvenient and increases the material cost. Therefore, various electromagnetic cooking utensils have been proposed in which an aluminum material and a magnetic material are appropriately combined and joined in consideration of lightness, corrosion resistance, cost, and the like.

[0004] For example, a relatively inexpensive magnetic material, soft iron, is clad in one or both sides with an aluminum material, or an aluminum-plated aluminized steel plate is formed into an electromagnetic cooking utensil. Electromagnetic cooking utensils in which a magnetic material is sprayed on a required portion of the outer surface of the utensil, electromagnetic cooking utensils in which a magnetic material is bonded to the bottom outer surface of an aluminum cooking utensil, and the like.

[0005]

However, an electromagnetic cooking utensil made of a clad material or an aluminized steel plate is provided with an aluminum material on the surface, but since the magnetic material is disposed on the entire utensil, only the magnetic material is used. Was less effective in reducing the weight than the cooking utensils manufactured in the above. For this reason, the inconvenience of handling has not been significantly improved. Also, the cost reduction effect was poor.

On the other hand, in an electromagnetic cooking utensil in which a magnetic material is provided on the outer surface of the utensil main body by the above-described thermal spraying or joining, since most of the utensil is made of aluminum, effects such as weight reduction and cost reduction are sufficiently achieved. Was in However, since the heating element is joined to the outer surface of the aluminum container, the aluminum material is interposed between the object to be cooked and the heating element to be put into the container, and the heat transfer is hindered, and the heat efficiency is high. It was difficult to use the electromagnetic cooking utensils.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide an electromagnetic cooking appliance having a high effect of reducing weight and an effect of reducing cost and having high heat efficiency, and a method of manufacturing the same.

[0008]

An electromagnetic cooking utensil according to the present invention will be described with reference to the drawings, in which an opening is formed at the bottom of an aluminum utensil main body (1) and electromagnetic induction is provided. A heating element (2) that generates heat due to the opening is arranged so as to close the opening, and the vessel body (1) and the heating element (2) are joined at their boundary. is there.

With the above configuration, since the heating element is disposed only in a portion required for induction heating, the weight of the cooking utensil can be sufficiently reduced, and the cost can be reduced. Further, the heating element can be brought into direct contact with the electromagnetic cooker, and the object to be cooked and the heating element come into direct contact, so that an electromagnetic cooking appliance with high thermal efficiency can be obtained.

The method of manufacturing an electromagnetic cooking utensil according to the present invention will be described with reference to the reference numerals in the drawings. ), A heating element plate (21) serving as a heating element (2) is fitted into the through hole (12), and then the aluminum plate (11) and the heating element plate (21) are fitted in the fitted state. Are joined to form a joining member (3), and the joining member (3) is formed into a container shape so that the heating element plate (21) is located at the bottom.

If the above method is adopted, the heating element plate is fitted into the through hole provided in the aluminum plate, and the two plates are joined in the fitted state, so that the positioning at the time of joining becomes easy, and In addition, the two plates do not shift during joining. In addition, since the two plates are joined in a state of being arranged on the same plane, the joining members can be manufactured by easily joining the two plates by a simple joining device or the like. In addition, since it is not necessary to use a special processing device or the like for forming the plate-like joining member into a vessel shape, the vessel for electromagnetic cooking can be easily manufactured.

Further, the aluminum plate (11) and the heating element plate (21) are preferably joined by friction stir welding.

If the aluminum plate and the heating element plate are joined by friction stir welding, the joining can be easily performed even with the above-mentioned dissimilar materials, and a sufficient joining strength can be obtained. . Further, since friction stir welding is a solid-phase welding, almost no distortion occurs, and there is no adverse effect on the subsequent forming into a vessel shape. in addition,
Since the friction stir welding apparatus can be implemented with simpler equipment than laser welding or the like, the manufacturing cost can also be reduced.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the invention according to claim 1, wherein (1) is a main body made of aluminum, and (2) is a heating element which generates heat by electromagnetic induction.

The vessel main body (1) is in the form of a pipe having a circular cross section with upper and lower ends open. Aluminum is adopted as the material in consideration of lightness, corrosion resistance, price, and the like.

The heating element (2) is in the form of a shallow, bottomed cylindrical vessel, and has an inner diameter and an outer diameter that substantially coincide with the vessel body (1). The heating element (2) is made of a magnetic substance because it needs to generate heat by electromagnetic induction. Specifically, ferrite-based SUS such as SUS430 and soft iron such as SS400 can be mentioned. Further, in order to improve corrosion resistance and decorativeness, a clad material in which the surface of the magnetic material is clad with aluminum, an aluminized steel plate in which aluminum is plated on the surface, or the like may be used. In particular, when the clad material or the aluminized steel sheet is used, by setting the thickness of aluminum to 200 μm or less, it is possible to impart corrosion resistance without affecting the electromagnetic induction action, and to be sufficient as a cooking utensil. This is preferable because a high thermal efficiency can be maintained.

Thus, the periphery of the lower end of the vessel main body (1) and the periphery of the upper end of the heating element (2) are aligned with each other, as described above.
The bottom opening of the container body (1) is closed by the heating element (2), and the association between the container body (1) and the heating element (2) is joined in the circumferential direction. Examples of such a joining method include friction stir welding, which will be described later, brazing, welding, friction joining, pressure welding, and the like.

According to the above configuration, since the heating element is disposed only at the bottom of the cooking utensil and its vicinity, that is, only at a portion necessary for induction heating, the weight of the cooking utensil can be sufficiently reduced. Costs can be reduced. Further, the object to be cooked put into the cooking utensil comes into direct contact with the heating element, and the heating element can come into direct contact with the electromagnetic cooking device, so that an electromagnetic cooking device with high thermal efficiency can be obtained.

In the case of this embodiment, the heating element (2)
Constitutes a bottom part of the vessel and a part of a rising part following the vessel, so that convection of water or the like put into the vessel for cooking can be activated, which is particularly preferable for rice cooking.

Next, FIG. 2 shows another embodiment of the invention according to claim 1, except that the shapes and mounting manners of the main body (1) and the heating element (2) are different. Since this is the same as the embodiment, the description of the overlapping part will be omitted.

The shape of the vessel main body (1) is a shape in which a hole (opening) penetrating in the thickness direction is provided at the bottom of the vessel having a bottomed cylinder, and has an L-shape whose longitudinal sections are opposed to each other. ing.

The shape of the heating element (2) is a disc shape, and can be fitted into a hole provided at the bottom of the vessel main body (1).

A hole (opening) provided at the bottom of the vessel main body (1) is closed by the heating element (2) in a fitted state, and the vessel body (1) and the heating element ( 2) is joined in the circumferential direction.

The method of manufacturing the electromagnetic cooking utensil in the embodiment shown in FIGS. 1 and 2 is not particularly limited.
Any method can be adopted. However, it is desirable to manufacture by the method as described later.

Although the electromagnetic cooking utensils having a cylindrical shape with a bottom have been described in both of the above embodiments, the electromagnetic cooking utensils according to the present invention are not limited to the above-described shapes, but have rectangular cross sections and rectangular corners. Any shape such as a rounded shape can be used.

Next, embodiments of the invention according to claims 2 and 3 will be described with reference to the drawings.

In FIG. 3, (11) is an aluminum plate serving as a vessel main body (1), and (21) is a heating element plate serving as a heating element (2).

The type of the aluminum material constituting the aluminum plate (11) is not particularly limited.
Considering the ease of molding, 1000 such as JIS1100
It is desirable to use a 3000 series alloy such as a series alloy or JIS3003. In addition, the shape can be arbitrarily selected depending on the use of the electromagnetic cooking utensil after molding.

As a material for forming the heating element plate (21), as described above, ferrite-based S such as SUS430 is used.
Examples thereof include soft iron such as US and SS400, and a clad material in which aluminum is clad on the surface of a magnetic material, or an aluminized steel plate in which aluminum is plated on the surface may be used. The shape of the aluminum plate (1
An aluminum plate (1), which has substantially the same thickness as that of 1) and is described later.
The shape is such that it can fit into the through hole (12) provided in the hole.

Next, as shown in FIG. 3 (b), a through hole (opening) (12) is formed in the aluminum plate (11) in the thickness direction thereof. The method of engraving the through-hole (12) is not particularly limited, and examples thereof include cutting using a drill or the like and shearing such as punching.

Next, as shown in FIG. 3 (c), a heating element plate (21) is fitted into the through hole (12),
As shown in (d), the aluminum plate (1) and the heating element plate (21) are joined. Examples of the joining method include friction stir welding, brazing, pressure welding, MIG welding, and laser / electron beam welding. In the case of this embodiment, a case where the friction stir welding is adopted will be described as an example.

In the friction stir welding, as shown in FIG. 4, a small-diameter cylindrical probe (41) protrudes and is integrally provided on an end axis of a large-diameter cylindrical support (42). Using a friction stir welding apparatus (4), a probe (41) rotated at high speed together with a support (42) is inserted into a metal joint to perform solid-phase welding. The probe (41)
Is formed of a heat-resistant material that can withstand frictional heat generated during welding.

Specifically, in a state where the heating element plate (21) is fitted into the through hole (12) of the aluminum plate (11),
The tip of the probe (41) of the friction stir welding apparatus (4) rotating at a high speed is brought into contact with the surface of the joint interface between the aluminum plate (11) and the heating element plate (21) or the vicinity thereof. Then, while the contact portion is softened and plasticized by frictional heat, the probe (41) is further pressed to insert the probe (41) into the contact portion, and the aluminum plate (11) and the heating element plate (21) are inserted. The probe (41) is inserted until the end surface of the support (42) comes into contact with the surface of the support (42). In this state, the probe (41) is moved along the contact portion between the aluminum plate (11) and the heating element plate (21).

The rotation of the probe (41) generates frictional heat, and the interface between the aluminum plate (11) and the heating element plate (21) is softened and stirred around the contact portion with the probe (41). The softening and stirring portion is cooled and hardened by the separation caused by the movement of the probe (41), and the aluminum plate (11) and the heating element (2) are joined. This phenomenon is sequentially repeated with the movement of the probe (41), and finally the aluminum plate (1) and the heating element (2) are joined over the entire circumferential direction, and the joining member shown in FIG. (3) is manufactured.

Next, the joining member (3) obtained as described above is formed into a vessel shape. Examples of the forming method include deep drawing and spatula drawing, and it is optional to apply ironing or the like. In addition, by mainly bending the heating element plate (21), as shown in FIGS. 1 and 3 (e), the heating element (2) reduces the entire bottom of the vessel shape and a part of the rising portion following it. The aluminum plate (1) may be formed so that the aluminum plate (1) forms an upright portion with a remaining vessel shape, and the aluminum plate (11) is mainly bent to be used for cooking as shown in FIG. It may be formed so that the heating element (2) is arranged only at the bottom of the container.

If the above method is adopted, the two plates are joined in a state where the heating element plate is fitted into the through hole formed in the aluminum plate, so that the two plates can be easily positioned and shifted. It can be joined without. Further, the joining operation can be performed from the same direction in a state where both plates are arranged on the same plane. In particular, since the joining of the two plates is performed by friction stir welding, the joining can be easily performed by a simple joining device. Even in the joining between the dissimilar materials, it is easy to join and obtain sufficient joining strength. Can be. Further, since friction stir welding is a solid-phase welding, almost no distortion occurs, and there is no adverse effect on the subsequent forming into a vessel shape. The plate-shaped joining member is formed into an object shape without using a special processing device or the like, and a conventional processing device such as deep drawing or spatula drawing can be used as it is.

The method for producing the utensil for electromagnetic cooking according to the first aspect of the present invention is not limited to the above method. In particular, in the case of the embodiment shown in FIG. 2, the vessel main body (1) is manufactured by casting or the like, and the heating element (2) is fitted into a hole (opening) provided at the bottom of the vessel main body (1). Thereafter, the boundary portions may be joined to produce an electromagnetic cooking utensil. In this case, since the joining portions are arranged on the same plane and can be joined from the same direction, the above-described joining method can be adopted.

In order to improve the bonding strength between the aluminum plate (11) and the heating element plate (21), FIGS.
As shown in (e), the inner peripheral portion of the aluminum plate (11) and the outer peripheral portion of the heating element plate (21) are engaged with each other,
The bonding may be performed by the bonding method described above. FIG.
The boundary shown in (a) is an inner peripheral portion of the aluminum plate (11) and an outer peripheral portion of the heating element plate (21) in order to increase a contact area between the aluminum plate (11) and the heating element plate (21). Is a corresponding taper. The boundary portion shown in FIG. 5B is used to increase the contact area as described above.
Thin plate portions (22) and (22) are integrally protruded from the peripheral edge portions of the aluminum plate (11) and the heating element plate (21), respectively.
This is a combination of the thin plate portions (22) and (22). FIG. 5 (c) shows a configuration in which the thin plate portions (22) and (22) are bent to further increase the contact area. FIG. 3D shows that a large number of pot-like holes (23) are formed by an electron beam or the like on a thin plate portion (22) protruding outwardly and integrally from the periphery of the heating element plate (21). The two plates are joined by deforming and filling a part of the aluminum plate (11) into the pot-shaped hole by pressure. FIG. 3E shows a mode in which a thin plate portion (22) integrally provided at the peripheral end of the heating element plate (21) is raised upward and bent inward. A thin plate portion (22) of the same shape is also provided at the peripheral end portion of 11), and they are joined by forcibly fitting them.

[0040]

According to the first aspect of the present invention,
The heating element is in the opening at the bottom of the aluminum container body,
An electromagnetic cooking utensil joined in a manner to close the opening. Therefore, since the heating element can be arranged only in a portion necessary for induction heating, the weight of the cooking utensil can be sufficiently reduced, and the cost can be reduced. Further, since the object to be cooked is in direct contact with the heating element and can be in direct contact with the electromagnetic cooker, an electromagnetic cooking appliance with high thermal efficiency can be obtained.

According to a second aspect of the present invention, a plate for a heating element is manufactured by fitting and joining a heating element plate to an aluminum plate, and the joining member is formed into a vessel shape for electromagnetic cooking. Since the container is manufactured, the positioning of the aluminum plate and the heating element plate at the time of joining is easy, and the two plates are not joined in a shifted state. Further, since the joints arranged on the same plane can be joined from the same direction, it is possible to easily join with a simple joining device or the like.

Further, the invention according to claim 3 includes:
Since the joining of the aluminum plate and the heating element is performed by friction stir welding, the joining can be easily performed even between the dissimilar materials, and a sufficient joining strength can be obtained. In addition, since friction stir welding is solid-phase welding, almost no distortion occurs, and there is no adverse effect on the subsequent forming into a vessel shape. Further, since the friction stir welding apparatus can be performed with simpler equipment than laser welding or the like, the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an electromagnetic cooking appliance according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing an electromagnetic cooking appliance according to another embodiment of the present invention.

FIG. 3 is a view showing a manufacturing process of the electromagnetic cooking utensil;
(A)-(e) are sectional views, respectively.

FIG. 4 is a view showing a friction stir welding method, and is a perspective view with a partial cross section.

FIGS. 5A to 5E are views showing a bonding state of the aluminum plate and the heating element plate, and FIGS. 5A to 5E are cross-sectional views.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Main body 2 ... Heating element 3 ... Joining member 11 ... Aluminum plate 12 ... Through hole 21 ... Heating element plate

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Masatoshi Enomoto 6,224 Kaiyamacho, Sakai City Showa Aluminum Co., Ltd. (72) Inventor Seiji Tazaki 6,224 Kaiyamacho Sakai City, Showa Aluminum Co., Ltd. 72) Inventor Naoki Nishikawa 6,224 Kaiyamacho, Sakai City Showa Aluminum Co., Ltd. (72) Inventor Naoshi Yasuoka 6,224 Kaiyamacho Sakai City, Showa Aluminum Co., Ltd.

Claims (3)

[Claims] An opening is formed at the bottom of an aluminum object main body, and a heating element that generates heat by electromagnetic induction is arranged so as to close the opening. An electromagnetic cooking appliance characterized in that 1) and a heating element (2) are joined at their boundary. 2. A through hole (12) penetrating in the thickness direction in an aluminum plate (11) serving as a vessel main body (1), and a heating element plate (21) serving as a heating element (2) is provided. After fitting into the through hole (12), the aluminum plate (11) and the heating element plate (21) are joined in the fitted state to produce a joining member (3), and the joining member (3) is A method for manufacturing an electromagnetic cooking utensil, characterized in that the heating element plate (21) is formed into a utensil shape such that it is located at the bottom. 3. The method according to claim 2, wherein the aluminum plate (11) and the heating element plate (21) are joined by friction stir welding.