JP3218452B2 - Heat-sensitive part structure of electromagnetic cooker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-sensitive part structure of an electromagnetic cooker for induction-heating a body to be heated such as a pot placed on a top plate by a heating coil.

[0002]

2. Description of the Related Art In an electromagnetic cooker, it is necessary to detect the temperature of a body to be heated in order to perform automatic cooking control. For this reason, it is common to dispose a heat-sensitive portion on the lower surface near the center of a top plate. FIG. 6 shows an example of a conventional heat-sensitive part structure.
Is shown in

In FIG. 1, reference numeral 2 denotes a top plate, 9 denotes a heat-collecting plate made of an aluminum material closely mounted on a lower surface thereof, 3 denotes a heating coil, and 5 denotes a coil holding case. Unit A is provided. The heat-sensitive part A is made of a temperature-sensitive rod 20 made of aluminum material.
Are vertically inserted into and supported by the coil holding case 5, and the upper end surface of the temperature-sensitive rod 20 is pressed against the lower surface of the heat collecting plate 9 by a spring 21. Temperature sensing rod 20
A through hole 22 is formed in the upper part of the housing, in which a temperature detecting element 13 protected by an insulating tube 12 is inserted and held, and a lead 16 led out from the temperature detecting element 13 is passed through a coil holding case to a temperature detecting circuit. It is connected.

[0004]

In the above-mentioned heat-sensitive portion structure, the entire temperature-sensitive rod 20 is made of a metal material, so that the heat transmitted from the heat-collecting plate 9 to the temperature-sensitive rod 20 is transferred to the rod portion or the spring 21. The heat capacity of the entire heat-sensitive portion A is large, and the temperature change of the heat collecting plate 9 is difficult to be detected sensitively, and it tends to take time for accurate temperature detection.

[0005] Further, in the conventional heat-sensitive part structure,
The temperature sensing element 13 is inserted into the through hole 22 formed in the temperature sensing rod 20.
Is inserted together with the insulating tube 12, so that the processing cost is high when the through hole 22 is formed in the temperature-sensitive rod 20, and the temperature detecting element 13 is inserted into the small through hole 22 together with the insulating tube 12. It took a lot of time and effort to assemble, and the assembly workability was low. In particular, when a plurality of temperature detecting elements are used to increase the temperature detection accuracy, the processing cost of the temperature-sensitive rod 20 is further increased, and the assembling workability is more likely to be further reduced.

The present invention has been made in view of such a point, and has excellent heat conduction performance from a heat collecting plate to a temperature detecting element, and can be manufactured easily and inexpensively with parts. It is an object of the present invention to provide a heat-sensitive part structure with high assembling workability.

[0007]

In order to achieve the above object, the present invention has the following arrangement.

[0008] The invention according to claim 1 is a heat-sensitive portion structure of an electromagnetic cooker in which a heated object placed on a top plate is induction-heated by a heating coil, and is arranged in close contact with a lower surface of the top plate. A heat sensing plate made of metal is pressed and provided on the lower surface of the heat collecting plate, and the temperature detecting element is sandwiched and fixed between the lower surface of the heat collecting plate and the heat sensing plate.

According to this structure, the heat from the heat collecting plate is transmitted to the temperature detecting element sandwiched between the heat collecting plate and the heat sensitive plate via the heat sensitive plate and also directly from the heat collecting plate. That is, the temperature of the object to be heated is detected quickly and accurately.

Further, since the temperature detecting element is sandwiched and fixed between the heat collecting plate and the heat sensitive plate, it is not necessary to form a hole for holding the temperature detecting element. Becomes unnecessary.

[Structure] The invention according to claim 2 is based on claim 1.
In the configuration according to the invention, the heat-sensitive plate is fixed and held on a heat-sensitive plate holding base made of resin, and the heat-sensitive plate holding base is elastically pressed against the heat collecting plate by a spring.

[Operation] According to this configuration, not only little heat is released from the heat-sensitive plate to the heat-sensitive plate holding base made of resin, but also
There is no direct heat conduction from the heat sensitive plate to the pressing spring, and the heat capacity of the heat sensitive plate itself is small. Therefore, the temperature of the heat-sensitive plate changes quickly in response to the temperature change of the heat-collecting plate.

[Structure] According to a third aspect of the present invention, in the structure of the second aspect, a concave groove is formed in the upper surface of the heat-sensitive plate, and the temperature detecting element is closely attached to the concave groove. It is engaged and held.

According to this structure, the temperature sensing element is held on the heat sensitive plate with a large contact area, and the heat conductivity from the heat sensitive plate to the temperature sensing element is high.

Further, since the concave groove for holding the temperature detecting element can be easily formed by pressing or the like, the processing cost is lower than forming a through hole. In addition, assembling the temperature detecting element into the concave groove is much easier and easier than the operation of inserting the temperature detecting element into the through-hole, so that the assembling workability is high. In particular, when a plurality of temperature detecting elements are used, it is more effective for reducing the processing cost and improving the assembling workability.

Here, in the invention according to claim 2 or 3, if the heat-sensitive plate is made of aluminum and the resin holder is made of polyphenylene sulfide (PPS), the above-mentioned function is effective. Demonstrate.

[0017]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of an electromagnetic cooker according to the present invention, and FIG. 2 is a plan view showing the internal structure thereof.

The main case 1 of the electromagnetic cooker is formed by joining an upper case 1a and a lower case 1b and screwing them together.
A top plate 2 made of a non-magnetic material is provided in a central opening of the upper case 1a, and a coil holding case 5 holding a heating coil 3 and a ferrite 4 is disposed close to and opposed to a lower surface of the top plate 2, so that heating is performed. It is configured such that a metal-made body to be heated (such as a pot) 6 placed on the top plate 2 is induction-heated with the energization of the coil 3. Various control devices including a control circuit board 7, an electric cooling fan 8, and the like are provided in a lower portion in the main body case 1.

A heat collecting plate 9 made of an aluminum material is provided on the lower surface of the top plate 2 in close contact therewith.
Is transmitted from the contact portion between the top plate 2 and the heated body 6 to the heat collecting plate 9, and a heat sensitive portion A for detecting the temperature of the heated body 6 is provided at a central portion of the heat collecting plate 9. The heating unit case 5 is provided so as to act on the heating unit.

FIGS. 3 to 5 show the detailed structure of the heat-sensitive portion A. FIG.

The heat-sensitive portion A is a heat-sensitive plate holding base 10 which is inserted and supported in the center of the coil holding case 5 so as to be vertically movable.
A heat-sensitive plate 11 fixed to the upper end thereof, two temperature sensing elements 13 protected by the insulating tube 12 and held on the heat-sensitive plate 11, and a heat-sensitive plate holding base 10 on the lower surface of the heat collecting plate 9. And a coil spring 14 for urging and pressing.

The heat-sensitive plate holder 10 is formed of a resin material having excellent heat resistance, such as polyphenylene sulfide, so that heat from the heat-sensitive plate 11 is not easily transmitted to the heat-sensitive plate holder 10 itself and the coil spring 14. . The heat-sensitive plate 11 is formed of a rectangular aluminum plate fitted and fixed to the heat-sensitive plate holding base 10, and a pair of concave grooves 15 is formed on the upper surface thereof in a bent manner in parallel. Each of them is engaged and held in close contact with a large contact area. Further, lead wires 16 derived from the respective temperature detecting elements 13 extend downward through the heat-sensitive plate holding base 10 and are connected to the circuit board 7.

Here, the depth of the concave groove 15 is set to be slightly shallower than the outer diameter of the temperature detecting element 13 including the insulating tube 12, and the heat-sensitive plate is pressed by the urging force of the heat-sensitive plate holding base 10 upward. In a state where 11 is entirely pressed against the lower surface of the heat collecting plate 9, the temperature detecting element 13 engaged and held in each concave groove 15 is sandwiched and fixed between the lower surface of the heat collecting plate 9 and the heat sensitive plate 11. The heat of the heat collecting plate 9 is
Not only is heat transmitted to the temperature detecting element 13 with a large contact area through the concave groove 15, but also the heat of the heat collecting plate 9 is directly transmitted to the temperature detecting element 13.

[0025]

As is apparent from the above description, according to the structure of the heat sensing portion of the electromagnetic cooker according to the present invention, the heat transfer performance from the heat collecting plate to the temperature detecting element is excellent, and the processing of the parts is simple. Thus, it was possible to provide a heat-sensitive part structure which can be manufactured at low cost and has high assembling workability.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an electromagnetic cooker according to the present invention.

FIG. 2 is a plan view showing the internal configuration of the electromagnetic cooker.

FIG. 3 is a longitudinal sectional view of a heat-sensitive part.

FIG. 4 is a plan view of a heat-sensitive part.

FIG. 5 is a perspective view of a heat-sensitive part.

FIG. 6 is a vertical cross-sectional view of a conventional heat sensitive part.

[Explanation of symbols]

 2 Top Plate 3 Heating Coil 9 Heat Collection Plate 10 Heat Sensitive Plate Holder 11 Heat Sensitive Plate 13 Temperature Sensing Element 14 Spring 15 Groove

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H05B 6/12

Claims (4)

(57) [Claims] 1. A heat-sensitive portion structure of an electromagnetic cooker for inductively heating an object to be heated placed on a top plate by a heating coil, wherein a metal plate is provided on a lower surface of a heat-collecting plate closely attached to a lower surface of the top plate. A heat-sensitive portion structure of an electromagnetic cooker, wherein a heat-sensitive plate is pressed and arranged, and a temperature detecting element is sandwiched and fixed between a lower surface of the heat-collecting plate and the heat-sensitive plate. 2. The heat-sensitive part of the electromagnetic cooker according to claim 1, wherein the heat-sensitive plate is fixedly held on a heat-sensitive plate holding base made of resin, and the heat-sensitive plate holding base is elastically pressed by a spring toward the heat collecting plate. Construction. 3. A groove is formed on the upper surface of the heat-sensitive plate by bending.
3. The heat-sensitive part structure of an electromagnetic cooker according to claim 2, wherein the temperature detecting element is closely engaged with and held in the concave groove. 4. The heat-sensitive part structure of an electromagnetic cooker according to claim 2, wherein the heat-sensitive plate is made of an aluminum material, and the resin holder is made of polyphenylene sulfide.