JP3258252B2 - Ferrite core mounting structure of rice cooker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a ferrite core mounting structure for a rice cooker having an electromagnetic induction heating structure.

[0002]

2. Description of the Related Art FIG. 6 shows a mounting structure of a ferrite core 1 of a rice cooker having a conventional electromagnetic induction heating structure. The ferrite core 1 is housed and held in a holding member 2. Three to eight ferrite cores 1 are prepared at equal intervals outside an induction heating coil 4 arranged on a lower surface of a protective frame 3 for housing an inner pot. Place and screw 5
And is fixed to the protective frame 3.

[0003]

However, in the mounting structure of the ferrite core 1, at least one screw 5 must be used to mount one ferrite core 1. A sensor for detecting the temperature of the inner pot is attached to the protective frame 3. Since the sensor is fixed by screws via a sensor mounting member, the number of fixing screws is combined with the ferrite core 1. And the cost increases. Furthermore, since each ferrite core 1 and sensor must be separately mounted at each mounting position, there is a problem that the number of assembly steps is large and the workability is poor. Therefore, an object of the present invention is to reduce the number of parts and the number of assembly steps by reducing the number of screws used for assembling a rice cooker and simultaneously attaching a ferrite core and a sensor.

[0004]

In order to solve the above-mentioned problems, a ferrite core mounting structure for a rice cooker according to the present invention provides a protective frame for accommodating an inner pot and the protective frame so as to be pressed against the bottom outer surface of the inner pot. Rice cooker comprising a sensor mounted at the center of the bottom of the frame via a sensor mounting member, an induction heating coil disposed on a lower outer surface of the protection frame, and a plurality of ferrite cores radially disposed outside the induction heating coil. A mounting portion provided on an outer end of the ferrite core, a receiving portion provided on an outer portion of the protective frame, and the mounting portion is fixed to the receiving portion, while a side portion of the ferrite core is mounted on the sensor mounting member. A holding portion provided with a guide portion for positioning the ferrite core, the holding portion holds the ferrite core between the protection frame and the ferrite core, and the inner end of the ferrite core has the induction heating. Beyond the inner periphery of yl is obtained so as to extend inwardly.

[0005] According to the ferrite core mounting structure of the rice cooker, the sensor mounting member to which the sensor is mounted is mounted on the protective frame with the outer end mounting portion of the ferrite core mounted on the protective frame. The ferrite core can be attached simultaneously while holding the core between the protection frame.

Further, since a guide portion for positioning the side portion of the ferrite core is provided on the holding portion of the sensor mounting member, mounting workability can be improved. further,
Since the inner end of the ferrite core extends beyond the inner peripheral edge of the induction heating coil and is close to the center of the bottom of the inner pan, the magnetic flux generated by the induction heating coil is concentrated, and the inner side is formed by eddy current through the protection frame. The pot can be reliably induction heated. In addition, variations in the electric field strength can be reduced.

In the rice cooker ferrite core mounting structure, it is preferable to provide a holding member for holding the ferrite core, and to provide the mounting portion on the holding member. With this configuration, the mounting portion can be easily formed.

Further, it is preferable that the mounting portion of the ferrite core has a hook shape, and the receiving portion of the protection frame has a hook portion for hooking the mounting portion. By doing so, the workability for attaching the ferrite core can be further improved, and the screws used for attaching the ferrite core can be eliminated.

[0009]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 and 2 show a rice cooker 10 having a ferrite core mounting structure according to a first embodiment of the present invention. The rice cooker 10 includes an inner pot 11 as in the prior art.
, An induction heating coil 13 arranged on the lower outer surface of the protection frame 12, and a plurality of ferrite cores 14 radially arranged outside the induction heating coil 13. Moreover, the rice cooker 10 of the present embodiment has a sensor mounting member 16 so as to be pressed against the center of the bottom of the inner pot 11.
This is a so-called center sensor structure in which the sensor 15 is attached to the bottom central outer surface of the protective frame 12 via the.

A receiving portion 18 is provided on an outer peripheral portion of the protection frame 12 at an upper end of a mounting position of the ferrite core 14. The receiving portion 18 has a substantially H-shaped configuration including a pair of ribs 19, 19 protruding from the outer surface of the protective frame 12 and a hook portion 20 provided to connect the ribs 19, 19. I have. In the present embodiment, the receiving portion 18 is 120
Three are provided at an interval. In addition, the protection frame 12
A sensor insertion hole 21 is provided at the center of the bottom of the sensor insertion hole, and an annular sensor mounting portion 22 is provided on the periphery of the sensor insertion hole 21 so as to project downward. The sensor mounting portion 22 is provided with a screwing portion 23 at an interval of 120 degrees so as to correspond to the receiving portion 18. Further, the sensor insertion hole 21
, A cylindrical portion 21a provided with a projection for preventing a sensor from protruding in an annular shape inward is provided to project upward.

Each of the plurality of ferrite cores 14 radially arranged has a substantially J-shaped rod shape along the outer surface shape of the protective frame 12, and a holding member 24 made of synthetic resin is integrally provided on the surface thereof. ing. A hook-shaped mounting portion that is hooked and latched on the hook portion 20 of the receiving portion 18 is provided at a radial end (hereinafter, referred to as an outer end and an opposite end is referred to as an inner end) of the holding member 24. 25 are provided and no screw holes are provided. The inner end of the holding member 24 is configured to be positioned between the sensor mounting member 16 and the protection frame 12.

The sensor mounting member 16 is shown in FIG.
As shown in (B), a disk-shaped substrate portion 27 for positioning and holding the sensor 15 and a holding portion 28 protruding from the outer peripheral portion of the substrate portion 27 are provided. The board part 2
7 is provided with a pair of locking holes 29, 29 for inserting and locking the locking legs 15 a of the sensor 15, and is spaced apart by 120 degrees so as to correspond to the screwed portions 23 of the protection frame 12. A screw hole 30 is provided. The holding unit 28
Is composed of a cylindrical guide frame 31 protruding from the outer peripheral edge of the substrate portion 27 and a flange portion 32 protruding outward from the upper end of the guide frame 31. In FIG. 3, reference numeral 33 denotes a hole for leading out a lead wire of the sensor 15, and reference numeral 34 denotes a reinforcing rib.

When the ferrite core 14 and the sensor 15 are mounted on the protection frame 12, the induction heating coil 13 is formed on the holding member 24 of the three ferrite cores 14 in a state where the induction heating coil 13 is disposed on the bottom outer surface of the protection frame 12. Mounting part 2
5 are respectively hooked and latched on the hook portions 20 of the receiving portions 18 formed on the protection frame 12.

Next, with the sensor 15 mounted on the sensor mounting member 16, the sensor 15 is inserted into the sensor insertion hole 21 of the protection frame 12, and the flange portion 32 of the holding portion 28 is inserted.
Of the holding member 24 is pressed by the upper end surface of the holding member 24. In this state, the screw hole 30 of the sensor mounting member 16 is made to correspond to the screwing portion 23, and the screw 35 is inserted through the screw hole 30 to the screwing portion 2.
Tighten to 3. Thereby, each ferrite core 14 is connected to the sensor mounting member 16 and the protection frame 12 via the holding member 24.
In addition, the induction heating coil 13 can be fixed to the outer peripheral surface of the protective frame 12 via the ferrite core 14.

As described above, in the ferrite core mounting structure of the present invention, since the inner end of the ferrite core 14 can be fixed by mounting the sensor mounting member 16 for mounting the sensor 15, the fixing screw mounts the sensor 15. Screws 35 for fixing, the number of fixing screws can be reduced, and the ferrite core 14 and the sensor 15 can be used.
And can be attached simultaneously. When arranging the ferrite core 14, the holding member 24 as described above is used.
It is only necessary to hook the mounting portion 25 formed on the receiving portion 18 of the protection frame 12, so that the mounting workability can be improved.

FIG. 4 shows a rice cooker 40 having a ferrite core mounting structure according to a second embodiment. The rice cooker 40 has a first
As in the embodiment, the protective frame 42 and the induction heating coil 43
, A ferrite core 44 and a sensor mounting member 46 for the sensor 45.

The protective frame 42 is provided with three screwing portions 48 projecting from the outer peripheral portion of the sensor insertion hole 47 at the center of the bottom at an interval of 120 degrees, and the annular sensor mounting portion 22 shown in the first embodiment is provided. Is not provided.

The ferrite core 44 has a length whose inner end extends inward by a dimension L beyond the inner peripheral edge of the induction heating coil 43. Further, a holding member 50 is provided on the ferrite core 44 as in the first embodiment.

As shown in FIG. 5, the sensor mounting member 46 includes a disk-shaped substrate portion 52 and a holding portion 53 including a guide frame 54 and a flange portion 55, as in the first embodiment. I have. A pair of guide portions 56 are provided on the upper surface of the flange portion 55 so as to be positioned on both sides of the holding member 50 of the ferrite core 44 at an interval of 120 degrees. In the present embodiment, each adjacent guide portion 56,5
6, a screw hole 57 for a screw is provided.

When the ferrite core 44 and the sensor 45 are mounted on the protective frame 42, the induction heating coil 43 and the ferrite core 44 are arranged on the outer peripheral surface of the protective frame 42 as in the first embodiment. Each ferrite core 44 is positioned between the guide portions 56 of the sensor mounting member 46.

Next, with the sensor 45 mounted on the sensor mounting member 46, the sensor 45 is
7, the screw hole 57 of the sensor mounting member 46 and the screwed portion 48 of the protection frame 42 are aligned with each other, and tightened and fixed with the screw 58.

As described above, in the ferrite core mounting structure of the second embodiment, the guide portions 56 and 5 for positioning the end of the ferrite core 44 on the sensor mounting member 46.
6, the mounting workability can be improved. In the mounted state, since the ferrite core 44 extends beyond the inner peripheral edge of the induction heating coil 43 and is close to the center of the bottom of the inner pot 41, the magnetic flux by the induction heating coil 43 is concentrated, and the ferrite core 44 passes through the protection frame 42. Inner pan 4 due to eddy current
1 can be reliably induction-heated. Further, variation in electric field strength can be reduced.

Incidentally, the ferrite core mounting structure of the rice cooker of the present invention is not limited to the above-described structure. For example,
In the first and second embodiments, the mounting structure of the sensor mounting member to the protection frame is not limited to screwing, and a locking projection or a locking groove is provided in the guide frame of the sensor mounting member. It is also possible to provide a stop groove or a locking projection and attach it by forcible fitting or a so-called bayonet. It goes without saying that the present invention can also be applied to a rice cooker using four or more ferrite cores.

[0024]

As is apparent from the above description, in the ferrite core mounting structure of the rice cooker of the present invention, a mounting portion is provided at the outer end of the ferrite core, and the mounting portion is mounted on the receiving portion of the protective frame. Since the ferrite core is held between the protection frame and the sensor mounting member for mounting the sensor, the ferrite core can be mounted at the same time by mounting the sensor mounting member.

In particular, since the guide portion for positioning the side portion of the ferrite core is provided on the holding portion of the sensor mounting member, mounting workability can be improved. The ferrite core has its inner end extending beyond the inner peripheral edge of the induction heating coil and close to the center of the bottom of the inner pan, so that the magnetic flux generated by the induction heating coil is concentrated, and eddy currents flow through the protection frame. Thereby, the induction heating of the inner pot can be surely performed. In addition, variations in the electric field strength can be reduced.

Further, since the holding member for holding the ferrite core is provided and the mounting portion is provided on the holding member, the mounting portion can be easily formed.

Further, since the mounting portion of the ferrite core is formed in a hook shape and the hook portion for hooking the mounting portion is provided on the receiving portion of the protective frame, the outer end of the ferrite core can be easily mounted. The mounting workability can be further improved. Further, according to this structure, a screw used for fixing the ferrite core is not required, so that the number of parts can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a rice cooker having a ferrite core mounting structure according to a first embodiment of the present invention.

FIG. 2 is an exploded sectional view of FIG.

FIG. 3 shows a sensor mounting member, (A) is a plan view,
(B) is a sectional view taken along line II of (A).

FIG. 4 is a cross-sectional view of a rice cooker provided with a ferrite core mounting structure according to a second embodiment.

FIG. 5 is a perspective view showing a sensor mounting member according to a second embodiment.

FIG. 6 is an exploded sectional view of a conventional ferrite core mounting structure.

[Explanation of symbols]

10, 40 ... rice cooker, 11, 41 ... inner pot, 12, 42 ...
Protective frame, 13, 43 ... induction heating coil, 14, 44 ... ferrite core, 15, 45 ... sensor, 16, 46 ... sensor mounting member, 18 ... receiving part, 24, 50 ... holding member, 25
... Mounting parts, 27, 52 ... Board parts, 28, 53 ... Holding parts,
56: Guide part.

Claims (3)

(57) [Claims] 1. A protective frame for accommodating an inner pot, a sensor attached to a center of a bottom of the protective frame via a sensor mounting member so as to be pressed against an outer surface of a bottom of the inner pan, and disposed on a lower outer surface of the protective frame. A rice cooker provided with an induction heating coil and a plurality of ferrite cores radially disposed outside the induction heating coil, wherein a mounting portion is provided at an outer end of the ferrite core and a receiving portion is provided on an outer portion of the protection frame. And a fixing portion provided with a guide portion for positioning a side portion of the ferrite core on the sensor mounting member, and the ferrite core is protected by the holding portion. Hold it between the frames,
A ferrite core mounting structure for a rice cooker, wherein an inner end of the ferrite core extends inward beyond an inner peripheral edge of the induction heating coil. 2. The ferrite core mounting structure for a rice cooker according to claim 1, wherein a holding member for holding the ferrite core is provided, and the mounting portion is provided on the holding member. 3. The mounting portion of the ferrite core has a hook shape, and the receiving portion of the protection frame includes a hook portion for hooking the mounting portion.
The ferrite core mounting structure of the rice cooker according to the above.