JP3291751B2 - Induction heating cooker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an induction heating cooker having a heating coil and a temperature sensor.

[0002]

2. Description of the Related Art In recent years, attention has been paid to the fact that induction heating cookers have excellent characteristics such as high efficiency and safety, and the development and production of induction heating cookers have become active. For this reason, in addition to improving the cooking performance, which is the basic performance of the induction heating cooker, other performance improvements such as a configuration with excellent productivity and low noise have been demanded.

FIG. 3 shows a conventional induction heating cooker.
This will be described with reference to FIG.

In FIG. 1, reference numeral 21 denotes a frame to which a plate 22 is fixed. Reference numeral 23 denotes a main body case made of resin, which has an intake port 24 on the front surface and an exhaust port 25 on the rear surface. The frame 21 and the main body case 23 are fixed.

[0005] Reference numeral 26 denotes a heating coil, which is formed by twisting a plurality of conductive wires into a spiral shape. Also, the coating of the conductor is
The coils are self-fused, and the coils are bonded and integrated by heating. Reference numeral 27 denotes a coil support unit, and a heating coil 26 is adhered to the upper surface with an adhesive.
The heating coil 26 is pressed and fixed to the coil support 27 by screwing the coil fixing claw 28 to the coil support 27. Reference numeral 29 denotes a heating coil unit, which assembles and integrates the heating coil 26 and the coil support 27. Reference numeral 30 denotes a joint, which has a hole formed in the outer periphery of the coil support portion 27, and fits the joint 30 into a boss 31 provided from the main body case 23 and fixes it with a screw, thereby connecting the heating coil unit to the main body. Attached to.

Reference numeral 32 denotes a metal body (hereinafter, referred to as a ferrite core) made of a high magnetic permeability material, which is fixed to the lower surface of the coil supporting portion 27 by bonding. This prevents leakage in the direction of the lower surface, which is the side, and suppresses the influence of noise on external devices due to the action of preventing magnetic force leakage, and reduces the magnetic force on the plate 22 side, so that the heating force is not reduced. Like that. Reference numeral 33 denotes a temperature sensor which is attached so as to be in contact with the lower surface of the plate 22 from the center of the heating coil 26, and detects the temperature of an object 34 to be heated such as a pot placed on the upper surface of the plate 22. A driving circuit 35 supplies a current for induction heating to the heating coil 26.
The temperature sensor 33 and the drive circuit 35 are electrically connected, and the drive circuit 3
5 will be controlled. Numeral 36 denotes a cooling fan provided in the vicinity of the intake port 24 for cooling heat-generating components in the drive circuit 35 and the like.

The operation of the induction heating cooker configured as described above will be described below. By placing the object to be heated 34 on the plate 22 and turning on a switch of an operation unit (not shown), the heating coil 26 and the drive circuit 35 provided inside the main body can be operated and heated.
At this time, if the temperature of the object to be heated 34 rises abnormally, the temperature sensor 33 detects the temperature, and the drive circuit 35 stops the current supplied to the heating coil 26, so that safety is maintained. It had been.

[0008]

However, in assembling the heating coil unit 29 as described above, for example, the heating coil 26 itself uses a self-bonding wire.
It is possible to perform a process of integrating the heating process,
Is fixed to the coil supporting portion 27 by an adhesive and a screw of the coil fixing claw 28, and the temperature sensor 33 is configured to be attached to the center of the heating coil 26 as a separate component. It was complicated and time-consuming.

Further, since there is nothing that protects the conductive wire of the heating coil 26, the heating coil 2
6 could be scratched. Further, in terms of performance, since the heating coil 26 is not entirely fixed to the coil supporting portion 27, the heating coil 26 easily vibrates at the frequency of the waveform of the current flowing through the heating coil 26. Was increasing. Further, at the time of heating, the temperature of the heating coil 26 is high near the center of the coil radius, and the temperature distribution varies considerably. For this reason, the cooling of the heating coil 26 is performed so that the cooling performance can be ensured even in a place where the temperature becomes high. Had to be done. further,
When attaching the temperature sensor 33, the temperature sensor 3
Due to the routing of the connection wires coming out of the coil 3, there is a problem in that the manner of noise rise differs due to the magnetic force generated from the heating coil 26, causing a difference in the temperature level determined by the drive circuit.

[0010] The present invention solves the above-mentioned problems, and facilitates assembling of a heating coil unit, eliminates damage to the heating coil during operation, reduces electromagnetic noise generated from the heating coil, and A first object is to provide an induction heating cooker in which the cooling performance of a heating coil is improved.

A second object of the present invention is to provide an induction heating cooker in which the assemblability of a temperature sensor is improved, the effect of noise of a heating coil on the temperature sensor is made constant, and as a result, the detected temperature level is stabilized. To provide.

[0012]

Means for Solving the Problems In order to achieve the above object, an induction heating cooker according to the present invention comprises:
Holding the heating coil wound in a spiral shape and the heating coil
And a coil having a joint for attachment to the main body
A support section and a drive circuit for supplying a current to the heating coil.
Equipped with a temperature sensor that detects the temperature of the object to be heated,
The temperature sensor is electrically connected to the drive circuit,
A high permeability material body is provided near the lower surface of the
Part or the whole of the high magnetic permeability material body with the core
Cover with a resin that forms the
Heating coil unit by fixing the heating coil to the oil support
And attached to the main body via the joint
The heating core of the signal line coming out of the temperature sensor
The heating coil and the heating coil
And a structure integrally fixed with the high-permeability material body.
You.

[0013]

DETAILED DESCRIPTION OF THE INVENTION The present invention by configuring the above reporting, since the heating coil and the high magnetic permeability material body and the coil support portion provided near the bottom of the heating coil is integrally formed, improving assembly of the heating coil unit In addition, since the periphery of the heating coil is covered with the resin of the coil supporting portion, it is possible to suppress the heating coil from vibrating during energization, and to reduce electromagnetic noise generated from the heating coil. Further, since the periphery of the heating coil is covered with the resin, it is possible to reduce damage to the heating coil which is erroneously attached during the assembling operation. Furthermore, the resin of the coil supporting portion surrounding the heating coil improves heat diffusion from the high-temperature portion to the low-temperature side of the heating coil, thereby suppressing heat concentration near the center of the coil radius of the heating coil,
Further, since the coil supporting portion is larger than the outer diameter of the heating coil, the heat radiating surface can be widened, and as a result, the cooling performance of the heating coil can be improved.

[0014] Also, since the temperature sensor and high magnetic permeability material body is provided near the bottom of the heating coil and the coil support portion are integrally formed, thereby improving assembling efficiency, emanating from the temperature sensors the heating Since the signal line closest to the coil is fixed at a fixed position by the resin of the coil support, the amount of noise caused by the heating coil entering the signal line of the temperature sensor is stabilized, and as a result, the level of the detected temperature is stabilized. You can do it.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

The same parts as those in the conventional example are denoted by the same reference numerals, and detailed description is omitted.

In FIG. 1, reference numeral 1 denotes a heating coil, which is formed by twisting a plurality of conductive wires in a spiral shape. Numeral 2 denotes a coil supporting portion made of resin, and the heating coil 1, the temperature sensor 3, and the ferrite core 4 are integrally formed by, for example, forming the coil supporting portion 2 at the same time. This integrated unit is referred to as a heating coil unit 5, in which a temperature sensor 3 is mounted on a central upper surface, a heating coil 1 is provided around the temperature sensor 3, and a ferrite core 4 is provided on a lower surface of the heating coil 1. The heating coil 1 is mounted parallel to the spiral direction. Reference numeral 6 denotes a joint, which is a hole formed in the outer periphery of the heating coil unit 5. The joint 6 is fitted into a boss 31 provided from the main body case 23 and fixed by screws, so that the heating coil unit 5 is Attached to. The heating coil 1 is connected to a drive circuit 35 so that a current for induction heating is supplied from the drive circuit 35. The temperature sensor 3 and the driving circuit 3
5 is electrically connected, and the operation of the drive circuit 35 is controlled by the temperature of the object 34 to be heated.

The operation of the induction cooking device configured as described above will be described below. By placing the object to be heated 34 on the plate 22 and turning on a switch of an operation unit (not shown), the heating coil 1 and the drive circuit 35 provided inside the main body can be operated and heated. At this time, the heating coil 1 tends to vibrate at the frequency of the current waveform flowing through the heating coil 1. However, since the heating coil 1 is surrounded by the resin of the coil supporting portion 2, the vibration is suppressed, and the heating coil 1 is vibrated. Therefore, the electromagnetic noise generated from the sound is reduced. During driving, the heating coil 1 particularly generates heat near the center of the coil radius. However, the heating coil 1 is heated by the resin of the coil supporting portion 2 which is in close contact with the heating coil 1.
Is moved to the low temperature side as indicated by arrows a, b, c, and d (see FIG. 2), thereby suppressing heat concentration near the center of the coil radius of the heating coil 1. As a result, the heating coil 1 Cooling performance can be improved.

Further, since the coil supporting portion 2 is larger than the outer diameter of the heating coil 1, the heat radiating surface can be widened and the cooling performance is further improved. Therefore, by utilizing the improvement in the cooling performance, it is possible to make the conductive wire of the heating coil 1 thinner, which has been difficult due to an increase in the amount of generated heat, and to reduce the price of the product.

Conventionally, when the temperature sensor is mounted separately from the heating coil, the way of routing the signal line coming out of the temperature sensor differs during assembly, and the magnetic field generated from the heating coil is different. Although there was a problem that the amount of noise entering the signal line of the temperature sensor was different for each product due to the influence, in this embodiment, the signal line closest to the heating coil 1 coming out of the temperature sensor 3 was placed at a certain position. Since the coil support 2 is fixed by the resin, the amount of noise entering the signal line of the temperature sensor 3 is constant, and as a result, the detected temperature level for each product can be stabilized.

Therefore, variation in temperature control for each product is greatly reduced. Further, the heating coil 1
Is covered with the resin of the coil support portion 2, so that the self-fusion process used for the conductor of the heating coil 1 for integrating the heating coil 1 is unnecessary, and the periphery of the heating coil 1 is made of resin. Because it is protected, the heating coil 1 is not accidentally damaged during assembly. When the cooling air sent from the cooling fan 36 hits the heating coil 1,
Since the outer surface is covered with the resin, the flow of the cooling air is smooth, and the noise due to the disturbance of the flow is reduced.

Also, in the present embodiment, the heating coil 1 and the ferrite core 4 are integrally formed in comparison with the conventional method in which the ferrite core is bonded to the lower side of the heating coil via a coil supporting portion. Therefore, the accuracy of the positional relationship between the heating coil 1 and the ferrite core 4 is improved, and the performance of preventing the magnetic force leakage of the ferrite core 4 can be most improved, that is, the ferrite core 4 is horizontal with respect to the spiral direction of the heating coil 1. Can be stably created.
Therefore, noise to other devices can be reduced by improving the performance of preventing magnetic force leakage.

Further, in assembling the heating coil unit 5, since the heating coil 1, the temperature sensor 3, and the ferrite core 4 are integrally molded with the resin of the coil supporting portion 2, the number of assembling steps is greatly reduced. . Therefore,
This reduction in assembly man-hours will result in a significant reduction in product prices.

In the present embodiment, the heating coil 1 and the temperature sensor 3 are formed integrally with the coil support 2, but any one of the combination of the heating coil 1 and the coil support 2 may be used. In addition, a part of the heating coil 1 and the temperature sensor 3 may be exposed from the resin of the coil supporting portion 2 at the time of integral molding.

Further, in this embodiment, the joint 6 is connected to the boss 3
Although a hole for fitting 1 is used, any plate or other protruding portion may be used. It is needless to say that a portion to be attached to the main body may be formed.

[0026]

As is clear from the above embodiments, according to the present invention, a high-permeability material body is provided near the lower surface of a heating coil, and a part or the whole of the heating coil and the high-permeability material body are formed. Since the coil is formed so as to be integrally covered with the resin forming the coil support, the heating coil unit is easy to assemble, which reduces the product price and eliminates the possibility of damaging the heating coil during the operation. It is possible to provide an induction heating cooker in which electromagnetic noise generated from the coil is reduced and the cooling performance of the heating coil is further improved.

Further, since the temperature sensor and a part or the whole of the high-permeability material body are formed so as to be integrally covered with the resin forming the coil supporting portion, the assemblability of the temperature sensor is improved and the product price is reduced. While reducing the effect of heating coil noise on the temperature sensor,
As a result, it is possible to provide an induction heating cooker in which the level of the detected temperature is stabilized.

[Brief description of the drawings]

FIG. 1 is a side sectional view of an induction heating cooker according to an embodiment of the present invention.

FIG. 2 is a sectional view of a heating coil portion of the induction heating cooker.

FIG. 3 is a side sectional view of an induction heating cooker in a conventional example.

FIG. 4 is a perspective view of a heating coil of the induction heating cooker.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heating coil 2 Coil support part 3 Temperature sensor 5 Heating coil unit 6 Joining part 23 Main body 35 Drive circuit

Continuation of front page (56) References JP-A-61-71581 (JP, A) JP-A-56-50089 (JP, U) JP-A-55-80897 (JP, U) JP-A-55-10291 (JP) , U) Fully open sho 60-168297 (JP, U) Fully open sho 61-82395 (JP, U) Fully open sho 56-15592 (JP, U) Really open sho 54-167056 (JP, U) (58) Field surveyed (Int.Cl. ⁷ , DB name) H05B 6/12

Claims (1)

(57) [Claims] A heating coil having a conductive wire spirally wound;
A temperature sensor for holding a heating coil and having a coil supporting portion having a joining portion for attachment to a main body, a drive circuit for supplying a current to the heating coil, and a temperature sensor for detecting a temperature of an object to be heated; Is electrically connected to a drive circuit, a high magnetic permeability material body is provided near the lower surface of the heating coil, and a part or the whole of the temperature sensor and the high magnetic permeability material body is formed of a resin forming the coil supporting portion. A heating coil unit is formed by integrally forming a cover and the heating coil is fixed to the coil support portion, and is attached to the main body through the joint portion, and is also provided from the temperature sensor.
The part of the signal line closest to the heating coil is
From the heating coil and the high-permeability material body
A fixed induction heating cooker.