JP3131356B2 - Ferrite core for electromagnetic induction heating cooker and its mounting structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for mounting a ferrite core for an electromagnetic induction heating cooker such as a rice cooker or a cooking pot of an electromagnetic induction heating type.

[0002]

2. Description of the Related Art FIG. 7 shows a conventional ferrite core and its mounting structure.
Reference numeral 3 denotes an inner body that forms an outer pan that accommodates the inner pan 101 together with the protective frame 102; 104a, an induction heating coil disposed on the outer bottom surface of the protective frame 102;
Reference numeral 105 denotes an induction heating coil disposed on the outer surface rising obliquely upward from the outer bottom surface of the ferrite core. As shown in FIG. 8, the ferrite core 105 has a substantially J-shaped curved rod shape and extends along the outer surface of the protective frame 102. After the ferrite core 105 is housed in the holding member 106 and fixed by an adhesive,
A plurality of the holding members 106 are radially arranged on the bottom of the protection frame 102 and are attached by screwing the center of the holding members 106 to the protection frame 102.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a ferrite core mounting structure which is easy to assemble.

[0004]

In order to achieve the above-mentioned object, the present invention is directed to a method in which an inner heating pot is disposed below an induction heating coil which is disposed opposite to an outer bottom surface and an outer side surface of the inner pan via a protective frame. In the mounting structure for a ferrite core for an electromagnetic induction heating cooker provided, a straight rod-shaped first ferrite core disposed below an induction heating coil facing the outer bottom surface of the inner pan via the protective frame.
The ferrite core and a straight rod-shaped second ferrite core disposed below the induction heating coil facing the outer surface of the inner pot via the protective frame are formed so that their axes intersect to form a certain angle. While holding by the holding member,
The holding member is sandwiched between the protection frame and a bottom member screwed to a bottom center portion of the protection frame or another member attached to the bottom body.

[0005]

[0006]

[0007]

[0008]

Next, an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows a rice cooker according to a first embodiment of the present invention. In the figure, 1 is an inner pot, 2 is a protective frame, 3 is an inner body, 4a is a first induction heating coil, 4b is a second induction heating coil, 5a is a first ferrite core, 5b is a second ferrite core, 6 Is a holding member, 7 is a bottom body, and 8 is a pressing member. The inner pot 1 is formed of a solid conductive material such as stainless steel or a clad material made of a conductive material of stainless steel as a base material and aluminum or an aluminum alloy as a joint material.

The protective frame 2 is made of a synthetic resin such as polyethylene terephthalate (PET) and has a shape that covers the outer bottom surface of the inner pot 1 and the outer surface extending obliquely upward from the outer bottom surface. At the center of the outer bottom surface of the protection frame 2, a boss 10 to which a fixing screw 9 of a bottom body 7 described later is screwed, and the boss 1
An annular mounting base 11 surrounding the periphery of the zero is formed.
A plurality of pairs of first guide members 12 that regulate the width direction of the holding member 6 are formed on the outer periphery of the mounting base 11. At the boundary between the outer bottom surface and the outer side surface of the protection frame 2, a boss 14 with which the temporary fixing screw 13 of the holding member 6 is screwed is formed. Further, a guide ring 15 projecting upward and a second guide member 16 projecting downward and regulating the radial direction of the holding member 6 are formed at the upper end of the protection frame 2. A plurality of pairs of third guide members 17 that regulate the width direction of the holding member 6 are formed around the inside of the second guide member 16. Reference numeral 18 denotes a fourth guide member that regulates the height direction of the holding member 6.

The inner cylinder 3 is formed by winding a printing steel plate into a cylindrical shape, and the lower end thereof is provided with a guide ring 15 of the protection frame 2.
Of the inner pot 1 together with the protective frame 2 by being inserted inside the inner pot. The first induction heating coil 4a and the second induction heating coil 4b are both spirally and densely wound. The first induction heating coil 4a is disposed so as to be in close contact with the bottom outer surface of the protection frame 2, and the second induction heating coil 4b is disposed so as to be in close contact with the outer surface of the protection frame 2. The first ferrite core 5a and the second ferrite core 5b are made of a sintered body of ferrite powder,
Each is a straight bar with a rectangular cross section.

The holding member 6 is formed of a synthetic resin material, and has an overall bent shape as shown in FIG. Ferrite core accommodating recesses 19a and 19b accommodating the first ferrite core 5a and the second ferrite core 5b, respectively, are formed on a surface of the holding member 6 extending from the bent portion on the convex side toward both ends. These ferrite core accommodating concave portions 19a and 19b are formed such that the axes of the first ferrite core 5a and the second ferrite core 5b accommodated therein intersect at a predetermined angle θ. This intersection angle θ is close to the angle at which the tangents of the outer bottom surface and the outer surface of the protection frame 2 intersect. On both sides of a surface extending from the concave bent portion of the holding member 6 to one end, curved edges 20 are formed along the outer surface of the protective frame 2. An ear 22 having a mounting hole 21 is formed on a side surface of the bent portion of the holding member 6.

The bottom body 7 has an outer shell 23 indicated by a two-dot chain line in FIG.
Together with this, it forms an outer body of the rice cooker. A protrusion 24 is formed at the center of the bottom 7 toward the boss 10 of the protective frame 2, and a screw hole 25 through which the fixing screw 9 is inserted is formed at the top of the protrusion 24. I have. The holding member 8 originally serves as a lid for covering control components and the like disposed on the bottom body 7, but also serves as a member for holding the holding member 6 against the protection frame 2.

Hereinafter, a method of assembling the rice cooker having the above-described configuration will be described. First, the first ferrite core 5
The method for forming the ferrite core 5a and the second ferrite core 5b will be described. These ferrite cores 5a and 5b are formed by filling a molding die with ferrite powder and sintering by a known method. Since the ferrite cores 5a and 5b have a straight shape, the structure of the molding die is simplified, and cracking does not occur during sintering. The first ferrite core 5a and the second ferrite core 5b are respectively formed from a standard ferrite molded body molded to a certain length from the first and second induction heating coils 4a and 4a.
It may be cut into a length corresponding to the region width of 4b before use. For example, for a rice cooker with a large capacity, FIG.
As shown in FIG. 3, the rice is cut into long pieces, and a small-sized rice cooker is cut into short pieces as shown in FIG. 3. By molding a standard ferrite core in this way, there is no need to prepare a plurality of types of ferrite cores according to the capacity of a rice cooker as in the conventional case, and the unit cost of parts can be greatly reduced.

The first ferrite core 5a and the second ferrite core 5b formed as described above are accommodated in the ferrite core accommodating recesses 19a and 19b of the holding member 6 and fixed by an adhesive. On the other hand, the protection frame 2 is turned upside down from the state shown in FIG.
Is provided, and the second induction heating coil 4b is provided on the outer surface. Subsequently, a plurality of holding members 6 accommodating and fixing the first ferrite core 5a and the second ferrite core 5b are prepared, and the first and second induction heating coils 4a and 4b are placed on the protective frame 2. Arrange radially through. Specifically, one end of each holding member 6 is held between a pair of first guide members 12 at the center of the protection frame 2, and the other end is held between a pair of third guide members 17 at the upper end of the protection frame 2. I do. Then, the temporary fixing screw 1 is inserted into the mounting hole 21 of the ear 22 of the holding member 6.
3 is screwed into the boss 14 of the protection frame 2 and the holding member 6 is temporarily fixed. The rotation of the holding member 6 that occurs during the turning of the temporary fixing screw 13 is prevented by the first and third guide members 12 and 17 located at both ends of the holding member 6.

Next, after attaching control parts and other necessary parts to the bottom body 7, the holding member 8 is installed at the center of the bottom body 7, and the protective frame 2 assembled as described above is placed thereon. Then, after inserting the inner body 3 into the guide ring 15 at the upper end of the protective frame 2, cover the outer body 23 and lower the lower body 7 with the bottom body 7.
Are fitted to the upper ends of the two, and the two are pressed and integrated. In this state, the fixing screw 9 is inserted into the screw hole 25 of the bottom body 7 and screwed into the boss 10 of the protection frame 2. Thereby, the bottom body 7 and the protection frame 2 are brought close to each other, and at the same time, the pressing member 8 is pressed against the holding member 6. As a result, the holding member 6 is attached to the protection frame 2.
And the holding member 8. The first induction heating coil 4a is sandwiched between the left half of the holding member 6 in FIG.
4 is held between the right half of the holding member 6 in FIG. 4 and the outer surface of the protective frame 2, so that it does not come off and fall off.

FIG. 5 shows a rice cooker according to a second embodiment of the present invention. The second embodiment is the same as the first embodiment except that the shape of the holding member 6 and the mounting structure thereof are different, and the corresponding parts are denoted by the same reference numerals and description thereof is omitted. As shown in FIG. 6, the holding member 6 has an engagement projection 26 at one end and a J-shaped hook 27 at the other end, instead of having the ear portion 22 unlike the holding member 6 of the first embodiment.
Is formed. On the other hand, an engagement hole 28 is formed in the mounting base 11 between the pair of first guide members 12 located at the bottom center of the protection frame 2, and a pair of third guide members 17 located at the upper end of the protection frame 2. An engagement hole 29 is formed in the fourth guide member 18 therebetween. Note that the second guide member 16 like the protection frame 2 of the first embodiment is not formed on the protection frame 2 because the second guide member 16 hinders the attachment of the holding member 6.

In order to assemble the rice cooker of the second embodiment having the above configuration, first, as shown in FIG. 6, a first ferrite core 5a and a second ferrite core 5b are formed in the same manner as in the first embodiment. It is housed and fixed in the holding member 6. Next, after the first induction heating coil 4a and the second induction heating coil 4b are disposed on the protection frame 2, the hook 27 at one end of the holding member 6 is engaged with the engagement hole 29 of the protection frame 2 while keeping the hook 27 engaged. The holding member 6 is turned around the hook 27 in the direction of arrow A and pressed toward the protection frame 2. As a result, the engaging protrusion 26 at the other end of the holding member 6 engages with the engaging hole 28 of the elastic mounting base 11, so that the holding member 6 is temporarily fixed without having to be screwed. Subsequent assembling procedures are the same as in the above-described first embodiment, and a description thereof will be omitted.

In the above two embodiments, the first ferrite core 5a and the second ferrite core 5b are fixed to the holding member 6 with an adhesive. The first ferrite core 5a and the second ferrite core 5b may be formed integrally with the holding member 6 by inserting the 5a and the second ferrite core 5b into a mold and performing so-called insert molding. Even if such insert molding is performed, the first ferrite core 5a and the second ferrite core 5b have a straight rod shape, and thus do not crack. The first and second ferrite cores 5a, 5b are formed by insert molding.
Since the fixing is performed simultaneously with the molding, the production process of the parts is shortened.

[0019]

As is apparent from the above description, according to the present invention, the holding member holding the first ferrite core and the second ferrite core is moved between the holding member and the bottom plate or another member attached to the bottom plate. , There is no need to fix the holding member alone. Further, when the holding member is held between the bottom plate and the protection frame, the induction heating coil is also held between the protection frame and the holding member, so that the holding member and the induction heating coil can be fixed at the same time, and the induction heating coil can be fixed. There is no need to fix the coil alone. Thus, since it is not necessary to fix the holding member and the induction heating coil independently,
Assembly is simplified.

[0020]

[0021]

[0022]

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of an assembly structure of a ferrite core according to the present invention.

FIG. 2 is an exploded perspective view of a ferrite core and a holding member.

FIG. 3 is a cross-sectional view of a holding member in which a ferrite core for a rice cooker having a small capacity is accommodated and fixed.

FIG. 4 is an exploded sectional view of FIG.

FIG. 5 is a sectional view showing a second embodiment of the assembly structure of the ferrite core according to the present invention.

6 is an exploded sectional view of FIG.

FIG. 7 is a cross-sectional view illustrating an assembly structure of a conventional ferrite core.

FIG. 8 is a perspective view of a conventional ferrite core.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Inner pot, 2 ... Protection frame, 4a, 4b ... First and second induction heating coils, 5a, 5b ... First and second ferrite cores, 6
... holding member, 7 ... bottom body, 8 ... holding member.

Claims (4)

(57) [Claims] 1. A mounting structure of a ferrite core for an electromagnetic induction heating cooker disposed below an induction heating coil disposed opposite to an outer bottom surface and an outer side surface of an inner pot via a protective frame, A first ferrite core in the form of a straight rod disposed below the induction heating coil facing the outer bottom surface of the inner pot via the protection frame; and an induction heating coil facing the outer surface of the inner pot via the protection frame. And a straight rod-shaped second ferrite core disposed below the holding frame is held by a holding member such that their axes intersect to form a certain angle, and the holding member is connected to the protection frame and the bottom of the protection frame. A mounting structure for a ferrite core for an electromagnetic induction heating cooker, which is sandwiched between a bottom member screwed to a central portion or another member attached to the bottom member. 2. The holding member is provided with an ear having a mounting hole for inserting a temporary fixing screw, and the temporary fixing screw is screwed into the protective frame to temporarily fix the holding member. A mounting structure for a ferrite core for an electromagnetic induction heating cooker according to claim 1. 3. An engaging projection is formed at one end of the holding member and a hook is formed at the other end, and an engaging hole is provided in the protective frame for engaging the engaging projection of the holding member with the hook. The mounting structure of a ferrite core for an electromagnetic induction heating cooker according to claim 1, wherein the holding member is temporarily fixed. 4. The ferrite core for an electromagnetic induction heating cooker according to claim 1, wherein a curved edge is formed on the holding member along the outer surface of the protection frame. Mounting structure.