JPH0622861A - Temperature sensor for electric cooker - Google Patents

Abstract

PURPOSE:To provide the constitution of the sensor for an electric cooker, in which not only electric insulation can be secured even in an atmosphere of 260-300 deg.C, but also sensitivity of the sensor is kept satisfactorily, and moreover, its assembly is carried out easily. CONSTITUTION:The temperature sensor constituted by combining in order an electric insulating plate 2 of a disk type, an electric insulating plate to which a lead wire 4 of a thermistor 3 is anchored, and a supporting base in which the lead wire 4 of the thermistor 3 is allowed to pass through a throughhole 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature sensor for an electric cooker such as an electric hot plate used at home.

[0002]

2. Description of the Related Art In recent years, electric hot plates have become widespread in general households. The baking plate is made of aluminum and the surface of which is coated with fluorine. The temperature sensor installed below the baking plate controls the temperature of the baking plate. One body is made of synthetic resin such as polypropylene. Further, as a feature of the products, the sales of products that raise the surface temperature of the baking plate (conventional temperature of 200 to 300 ° C.) to 250 to 270 ° C. and appeal the feeling of heat during cooking are increasing. As shown in FIG. 4, the conventional temperature sensor unit has a thermistor element 31 inserted in a Teflon tube and is inserted into a through hole provided on a side surface of a heat plate 32 which is an aluminum cylinder, and the heat plate 32 is heated. The coil spring 34 presses the inner surface of the stainless steel cylindrical pot-shaped cap 35 through the contact plate 33 pressed against the lower part of the. 36
Is a grill plate for cooking, and is in contact with the top surface of the cap 35. 37 is a sheathed heater which is a heat generating part,
38 is a heat shield for preventing radiation of the sheathed heater 37, 39
Is a cap holder for locking the cap 35, which is fixed to the sensor base 40 with screws, and the sensor base 40 is also fixed to the body 41 with screws. Moreover, in order to reduce the cost of the control circuit, the temperature sensor may be connected to one charging part of AC100V without using an insulating transformer, and the temperature sensor part needs to be electrically insulated from the outside. It was

[0003]

However, the thermistor element can only be used within a temperature limit of 250 to 266 ° C. of the Teflon tube, which is an electrical insulator, and the sensor sensitivity is increased in order to further raise the surface temperature of the baking plate. There was a need for a temperature sensor structure that is good and has heat resistance and electrical insulation.

Therefore, the present invention solves the above-mentioned conventional problems, and an object thereof is to provide a structure of a temperature sensor which has an electric insulation property even at 260 to 300 ° C., has a good sensor sensitivity, and is easy to assemble. That is.

[0005]

In order to achieve the above object, the present invention provides an electric insulation having a cylindrical metal cap, a disk-shaped electric insulating plate A, and a plurality of notched groove portions. A combination of a plate B, a thermistor element having a lead wire moored in the cutout groove portion of the electric insulating plate B, and a ceramic support base provided with a through hole A through which the lead wire of the thermistor element is inserted. It is arranged as follows.

In the same manner, in order to achieve the above-mentioned object, the second means is to provide a plurality of holes A or cutout holes A in the electric insulating plate A, and to provide the electric insulating plate A and the electric insulating plate B. And a heat compound between them.

[0007] Similarly, in order to achieve the above object, the third means is provided with a hole B in the central portion of the electric insulating plate B.

Also, in order to achieve the above object, the fourth means is provided with a recess at the center of the upper surface of the support base.

Also, in order to achieve the above-mentioned object, the fifth means is provided with a plurality of protrusions on the side surface of the support base, which are in contact with the inner surface of the metal cap.

Also, in order to achieve the above-mentioned object, the sixth means is provided with a fitting portion at the lower part of the support base for fitting with a coil spring for biasing upward.

[0011]

In the present invention, the electric insulator is interposed between the cap and the thermistor element by the above-mentioned first means.
Since the lead wire of the thermistor element is moored to the electric insulating plate B, the lead wire length in the heat receiving part becomes large, and the heat is also received from the lead wire, so the heat receiving area increases and the heat from the top surface of the cap is increased. It becomes easier to receive heat and the sensor sensitivity improves. Further, since the lead wire of the thermistor element is anchored in the notched groove portion of the electric insulating plate B, it can be easily assembled and easily positioned. In the assembly of the sensor as a whole, after passing the lead wire of the thermistor element fixed to the electric insulating plate B through the through hole A of the support base, the electric insulating plate A,
Then, by inserting the support base, the work can be easily performed.

Next, the second means is the above-mentioned second means, and the electrical insulating plate A is provided between the thermistor element and the cap.
It is electrically insulated with, but electrical insulation board A and electrical insulation board B
The thermal compound provided therebetween contacts the inner top surface of the cap through the plurality of holes A or the notched holes A provided in the electric insulating plate A. As a result, the thermistor element and the inner top surface of the cap are connected by a heat compound, heat transfer becomes smooth, and the sensor sensitivity is improved. Next, in the third means, when the thermistor element is moored to the electric insulating plate B by the above-mentioned third means, the sensing portion of the thermistor element falls into the hole B of the electric insulating plate B, and positioning becomes easy, Assemblability is improved.

The fourth means is that the lead wire of the thermistor element fixed to the electric insulating plate B is passed through the through hole A of the supporting base by the above-mentioned fourth means, and the electric insulating plate B is placed on the upper surface of the supporting base. In the case of fixing to the above, since the electric insulating plate B can be dropped into the concave portion provided in the central portion of the upper surface of the support base,
Easy positioning and easy assembly.

Next, in the fifth means, the support base and the inner surface of the cap are brought into contact with each other by the plurality of projections provided on the support base by the above-mentioned fifth means, so that the temperature of the side surface of the cap due to the radiation of the heater is increased. The rise is prevented from being transmitted to the support. As a result, the temperature of the baking plate in which the thermistor element contacts the top surface of the cap is easily picked up, and the sensor sensitivity is improved.

In the sixth means, since the fitting portion for positioning the coil spring is provided in the lower portion of the support base by the above-mentioned sixth means, the molding is easy and the assembly is easy, and the coil spring is positioned even during use. Since it is regulated, the coil spring will not be displaced.

[0016]

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

In FIGS. 1 and 2, reference numeral 1 denotes a cylindrical cap made of stainless steel or aluminum and having a flat top surface, which is made of a metal, and 2 denotes a thermistor which is pressed against the inside of the top surface of the cap 1. An electric insulating plate A that electrically insulates the lead wire 4 of the element 3 and the cap 1 from each other.
It consists of a 0.15 mm laminated mica plate. A plurality of notched groove portions 5 are provided in order to improve heat sensitivity of the sensor 5 by also receiving heat from the lead wire 4, and the thermistor element 3 is provided.
The thermistor element 3 and the lead wire 4 are formed and fixed in a Z-shaped or S-shaped constant shape by mooring the lead wire 4 of FIG. It is composed of 4 to 1.0 mm mica. Further, in order to improve the thermal conductivity, a thermal compound 7 made of silicon oil is applied on the upper surface of the electric insulating plate B5 on which the thermistor element 3 is present, and the electric insulating plate A2
If a plurality of holes A8 or cutout holes A9 are provided in the vicinity of the outer circumference of the cap 1, the thermal compound 7 contacts the top surface of the cap 1 through the holes A8 and cutout holes A9. As a result, the thermistor element 3 and the lead wire 4 are connected to the top surface of the cap 1 through the thermal compound 7, and the sensitivity of the thermistor element 3 is improved.

If a hole B10 having a size of about the thermistor element 3 is provided in the center of the electric insulating plate B, the thermistor element 3 is positioned when the lead wire 4 is moored to the electric insulating plate B. , Work easier. Further, the thermistor element 3 has a larger height dimension than the lead wire 4, but if the thermistor element 3 fits in the hole 10, the distance between the electric insulating plate A2 and the electric insulating plate B5 can be made narrower and the cap 1 The heat sensitivity of is even better.
Reference numeral 11 is a support base made of ceramics such as alumina. The upper surface has a recess 12 at the center for positioning and dropping the electric insulating plate B5, two through holes A13 through which the lead wire 4 is inserted, and the cap 1 of the cap 1. A fitting portion 1 for positioning a coil spring 14 for urging the support base 11 upward at the bottom portion by providing a plurality of protrusions 21 on the side surface that abut against the inner side surface.
5 is provided. Reference numeral 16 denotes a baking plate for cooking, which is formed by aluminum die casting, and the top surface of the cap 1 is in contact with the bottom surface thereof. 17 is the grill plate 1
A sheathed heater for heating 6 is also in contact with the bottom surface of the baking plate. Reference numeral 18 denotes a heat shield plate which prevents heat radiation of the sheathed heater 17 and is formed of a surface-treated steel plate. Reference numeral 19 denotes a cap holder, and the cylindrical portion of the cap 1 penetrates through the central portion, and the flange A22 at the lower end of the cap 1
Is formed so as to be locked, and the flange portion 23 at the lower end thereof is fixed to the sensor base 20 with a screw or the like. The sensor base 20 is molded of phenolic resin, a central portion thereof is provided with a concave portion so that the coil spring 14 can be fitted to the position regulation, and the lower portion of the body is also fixed with screws or the like.

The operation of the electric cooking temperature sensor configured as described above will be described.

The baking plate 16 is heated by the energization of the sheath heater 17, and the baking surface temperature of the baking plate 16 passes from the cap 1 through the electric insulating plate A2 to the thermistor element 3
Be transmitted to. At this time, the S moored to the electric insulating plate A2
Since the heat is also received from the lead wire 4 positioned in the character shape, the heat sensitivity performance as a sensor is improved. In addition, since the position of the lead wire 4 of the thermistor element 3 can be easily regulated by the notch groove portion 6, not only the assemblability is improved, but also the quality of the sensor sensitivity is improved. Further, in the assembly of the entire sensor, the thermistor element 3 is attached to the electric insulating plate B, and the lead wire 4 is attached.
After assembling into the support base 11, the electric insulating plate A2, the electric insulating plate B5, and then the support base 11 are inserted into the cap 1 to facilitate the work.

The thermal compound 7 between the electric insulating plate A2 and the electric insulating plate B5 connects the cap 1 and the thermistor element 3 through the hole A8 and the cutout hole A9, so that the heat conduction is improved and the sensor sensitivity is improved. Is improved.

When the thermistor element 3 is attached to the electric insulating plate B, the hole B10 is positioned and not only easy to assemble, but also the thermistor element 3 enters the hole B10. Therefore, if the electric insulating plate A2 and the electric insulating plate B5 are separated from each other. As a result, heat sensitivity is improved.

Since the electric insulating plate B5 with the thermistor element 3 inserted into the recess 12 of the support base 11, it is easy to assemble,
Since the position of the thermistor element 3 is fixed, the sensitivity performance is also stable.

There is heat radiation from the sheathed heater 17,
Even if the temperature of the side surface of the cap 1 rises, the contact area of the projection 21 of the support base 11 with the inner surface of the cap 1 is small, so that heat transfer to the thermistor element 3 is small and the sensor sensitivity is stable.

Since the coil spring 14 fits into the fitting portion 15 and its position is regulated, it is easy to assemble and stable movement is possible even during use.

[0026]

As described above, the object of the present invention is 260
It is possible to provide a temperature sensor having electrical insulation even at temperatures up to 300 ° C, good sensor sensitivity, and good assembling.

[Brief description of drawings]

FIG. 1 is a front sectional view of an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the temperature sensor according to the embodiment of the present invention during assembly.

FIG. 3 is a perspective view of an electric insulating plate B according to an embodiment of the present invention.

FIG. 4 is a sectional view showing a conventional example of a temperature sensor.

[Explanation of symbols]

 1 Cap 2 Electric Insulation Plate A 3 Thermistor Element 4 Lead Wire 5 Electric Insulation Plate B 6 Notch Groove 7 Thermal Compound 8 Hole A 9 Notch Hole A 10 Hole B 11 Support Base 12 Recess 13 Through Hole A 14 Coil Spring 15 Fitting Part 21 Projection

Claims (6)

[Claims] 1. A cylindrical metal cap, a disk-shaped electric insulating plate A, an electric insulating plate B having a plurality of cutout grooves, and a lead wire in the cutout groove of the electric insulation plate B. A temperature sensor for an electric cooker in which a thermistor element moored with and a ceramic support base provided with a through hole A through which a lead wire of the thermistor element is provided are sequentially combined. 2. The electric cooking according to claim 1, wherein the electric insulating plate A is provided with a plurality of holes A or notched holes A, and a heat compound is provided between the electric insulating plate A and the electric insulating plate B. Dexterous temperature sensor. 3. A temperature sensor for an electric cooker according to claim 1, wherein a hole B is provided in a central portion of the electric insulating plate B. 4. The temperature sensor for an electric cooker according to claim 1, wherein a recess is provided in the center of the upper surface of the support base. 5. A temperature sensor for an electric cooker according to claim 1, wherein a plurality of protrusions are provided on the side surface of the support base so as to abut against the inner surface of the metal cap. 6. The temperature sensor for an electric cooker according to claim 1, wherein a fitting portion for fitting a coil spring for urging upward is provided in a lower portion of the support base.