JP3027881B2 - Temperature sensor for 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 temperature sensor for controlling a cooking utensil which is in contact with a heating target of a cooking utensil used at home or the like and senses the temperature of the heating target.

[0002]

Conventional this type of cooking methods shown in FIG.
In FIG. 5 , the cooking utensil 1 is configured to measure the temperature of the object to be heated 3 by using a temperature sensor 2 for the cooking appliance.

As shown in FIG. 6 , a conventional temperature sensor 2 for a cooker is provided with a head 5 made of metal at the tip of a cylindrical support 4 as shown in FIG. An electrical insulator 6 was bonded to the head 5 by brazing or the like, and the insulator 6 was provided with a temperature-sensitive material 7. Reference numeral 8 denotes an electric terminal attached to the temperature thermosensitive element 7. The temperature-sensitive body 7 has a temperature-sensitive film provided on one surface of an alumina substrate by means such as vapor deposition or sputtering. Therefore, the temperature-sensitive body 7 may be attached to the head 5 in a case where the temperature-sensitive film side is attached to the insulator 6 or in a case where the alumina side is attached to the insulator 6. Since alumina has good thermal conductivity, the time required for temperature detection is almost the same in any case. After the temperature sensible body 7 is brought into contact with the insulator 6 as described above, as shown in FIG. 6 , the sealing is performed by sealing with an electric insulator 11, for example, glass, or by applying a mechanical force such as a spring. It is fixed (for example, JP-A-57-19525).

The head 5 and the support 4 are fixed by providing a flange 9 at the tip of the support 4 and attaching the head 5 to the flange 9.
The outer peripheral portion 10 is welded by contact. The temperature sensing element 7 of the cooker temperature sensor 2 controls the cooking utensil 1 by sensing the temperature of the object 3 to be heated.

[0005]

However, in the above-described configuration, it takes time for the object to be heated 3 and the temperature-sensitive body 7 to have substantially the same temperature. This is, in part, the object to be heated 3
This is because, in the path through which heat is transferred from the heat-sensitive element 7 to the temperature-sensitive element 7, the insulator 6 having a poor thermal conductivity is included.
The insulator 6 prevents the metallic head 5 and the temperature-sensitive film from electrically contacting each other, and also forms a gap between the head 5 and the insulator 6 and between the insulator 6 and the temperature-sensitive body 7. Eliminating heat conduction. However,
The heat conduction of the insulator 6 is not good, and considering the variation in the manufacturing process, it is necessary to make the thickness 0.3 mm or more. Therefore, it takes a considerable time until the temperature of the object to be heated is sufficiently transferred to the heat-sensitive element.

It is also conceivable to directly bond the head 5 and the surface of the temperature-sensitive body 7 having no temperature-sensitive film by brazing or the like except for the insulator 6, but the head 5 and the support 4 are welded. In the joining configuration, the head 5 needs to be convex with respect to the outer surface in order to improve the contact with the object to be heated. Therefore, the inner surface becomes concave, and attaching the temperature sensible body 7 to this concave portion is difficult because the joining surface between the head 5 and the temperature sensible body 7 is a dissimilar material, it takes a lot of man-hours, and is difficult to automate. Process. For this reason, a method has been adopted in which the head 5 and the temperature-sensitive material 7 are joined via the insulator 6. Therefore, the thermal responsiveness of the cooker temperature sensor 2 was not so good.

[0007] If the thermal response of the cooker temperature sensor is not good, the following occurs. That is, the object to be heated 3
When the hot water is boiled, even if the operation of the cooking utensil 1 is stopped when the hot water is boiled, a state occurs in which the hot water is not stopped even though the hot water is boiling and spilling.
In addition, in the case of cooking top plastic, since the heat response of the temperature sensor 2 for the cooker to the object to be heated 3 is poor, there is a risk that the cooking oil is abnormally heated and ignites.
From the above, when trying to control the cooking utensil 1 using the temperature of the heated object 3 using the temperature sensor 2 for the cooking device, the temperature of the heated object 3 cannot be accurately captured, and thus the appropriate control cannot be performed. Had.

Also, from the manufacturing point of view, when welding the head 5 and the flange 9 of the support 4, the flange 9 and the head 5 are welded.
Since the contact surface of the outer peripheral portion 10 is a welded surface, a smooth surface is required, and welding is performed after high-precision processing is required. Therefore, there was a problem that the processing for obtaining the smooth surface of the flange 9 and the head 5 was costly.

The present invention solves the above-mentioned conventional problems, and improves the thermal responsiveness of a temperature sensor to an object to be heated so that cooking can be easily performed without failure, and safe, convenient, and easy to manufacture. It is an object of the present invention to provide an easy-to-use and low-cost cooking appliance.

[0010]

Means for Solving the Problems In order to solve the above-mentioned problems, a temperature sensor for a cooking appliance of the present invention has the following configuration.

That is, the sensor head comprises a sensor head made of a good thermal conductive electrical insulator whose outer surface is in contact with an object to be heated, and a support for supporting the sensor head. Inside
Configuration consisting of a temperature-sensitive body provided in contact with
Between the sensor head and the temperature sensitive element.
Heat transfer from the head to the thermosensitive body is easily performed.
In this case, a heat conduction promoting film is provided.

Further, the sensor head made of a good thermal conductive electric insulator is brazed to a metal support.

A sensor head made of an electrical insulator having good thermal conductivity is formed by forming a tungsten or molybdenum film on the sensor head side on a metal support and brazing the support side using a high-temperature brazing material. Configuration.

Further, a sensor head made of an electric insulator having good thermal conductivity is brazed to a metal support by using a low-temperature brazing material of silver + copper + titanium.

Further, a configuration is used in which the sensor head and the support are joined to each other with another component interposed therebetween. That is, a sensor head portion including a hole provided in the metal plate and a sensor head attached so as to cover the hole, a fitting body, and a support body, and an outer peripheral portion of the sensor head portion and the fitting body are formed. The crimping process is performed between them, and the fitting body is pressed into the support body.

The sensor head comprises a hole provided in a metal plate or an insulator and a sensor head mounted so as to cover the hole, and a support. The outer periphery of the sensor head and the support are provided. It was configured to be attached to the flange.

[0017]

According to the present invention, the following functions are provided by the above configuration.

That is, since the heat conduction promoting film is provided on the sensor head made of an electric insulator having good heat conductivity , the heat of the object to be heated can be easily transferred to the heat-sensitive portion of the sensor.

Further, by providing a heat conduction promoting film between the sensor head and the temperature-sensitive material, it is possible to eliminate voids due to irregularities on these surfaces, thereby further improving heat conduction.

Further, since the sensor head and the temperature-sensitive material can be made of the same material, the joining thereof by brazing or the like becomes very simple.

Furthermore, since the sensor head of the electrical insulator and the metal or the metal and the metal are joined by brazing, the joining is facilitated.

When the sensor head portion and the fitting body are joined by caulking, the automation can be easily performed.

[0023]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Parts having the same functions as those of the conventional example are denoted by the same reference numerals, and description thereof is omitted. It should be noted that the method of using it for cooking utensils is the same as that shown in FIG.

[0024] Example 1 Figure 1 shows a cooking appliance temperature sensor 2 of the first embodiment of the present invention. In FIG. 1, the sensor head 12 is made of an electric insulator having good heat conductivity. Further, since the outer surface is in contact with the object to be heated 3, the outer surface is required to be a material having excellent thermal mechanical strength. Examples of such a material include alumina, magnesia, and aluminum nitride, but alumina is practically used including cost. 13 is a temperature-sensitive film
It is provided directly on the inner surface of the sensor head via the heat conduction promoting film 16 . In addition, the temperature sensing element transfers heat to the sensor head.
It is provided via the conduction promotion film 16. 8 is a temperature-sensitive film 13
Electrical terminals attached to In this embodiment, the sensor head having the above-described configuration is attached to the support 4 by brazing with the brazing material 14. After that, an emitting body and a holding mechanism (both not shown) for holding the emitting body may be provided inside the support body 4 so that the object to be heated 3 and the sensor head are easily brought into close contact with each other. If necessary, the temperature-sensitive film 13 may be sealed with an insulating material such as glass.

In this embodiment, the path through which the heat of the object 3 is transferred to the temperature-sensitive film 13 is only a sensor head having good heat conduction in the middle, so that the temperature of the object 3 can be reduced in a short time. Accurate detection was possible.

Further, the cooking appliance temperature sensor 2 obtained in the present embodiment was attached to the cooking utensil 1 shown in FIG. 5 for cooking. When the hot water was boiled in the heated object 3, the operation of the cooking utensil 1 was stopped immediately after the hot water boiled, and the hot water did not spill. Furthermore, when the oil temperature was set to 220 ° C. in the cooking of the tempura, the cooking utensil 1 was controlled when the oil temperature reached 220 ° C., and the oil temperature did not reach 220 ° C. or higher.

As described above, when the temperature sensor 2 for a cooker according to the present invention is used, the cooking can be performed with ease because of its good thermal response.

Further , the heat conduction promoting film 16 is provided when there is a possibility that a gap may be formed when the contact surface between the sensor head 12 and the temperature-sensitive body 15 is in rough contact. This is because the void in the contact surface has a heat insulating effect. Therefore, the thickness of the heat conduction promoting film 16 is such a thickness as to remove the voids, and in this embodiment where it is not necessary to consider electrical insulation,
Zero microns is sufficient. If the thickness is too large, the heat conduction of this film is further poor, and conversely, the heat transfer is reduced. This tendency depends on the thermal conductivity of this film, but is 100
If it exceeds a micron, the heat conduction is extremely reduced and the thermal response becomes poor.

The heat conduction promoting film 16 is preferably a film whose shape and thickness can be freely changed depending on the size of the gap. As such a material, silicone grease, wax, or the like is used. In order to improve the thermal conductivity, a ceramic powder having good thermal conductivity such as alumina or silica may be added.

When the temperature sensor 2 for a cooker obtained in the present embodiment was attached to the cooking utensil 1 and cooking was performed in the same manner as in the first embodiment, the same results as in the first embodiment were obtained.

Embodiment 2 In this embodiment, as shown in FIG. 2 , a temperature sensitive element 15 is bonded to the sensor head 12 by brazing with a brazing material 17. Sensor head 12
Since the substrate of the thermosensitive material 15 is made of the same material, it can be easily bonded. Also, it can be easily automated.

When the temperature sensor for a cooker obtained in the present embodiment was attached to the cooking utensil 1 and cooking was performed in the same manner as in the first embodiment, the same results as in the first embodiment were obtained.

In the above embodiments, the relationship between the sensor head and the temperature-sensitive material or the temperature-sensitive film has been described. The joining between the sensor head and the support will be described below.

Embodiment 3 In FIGS. 1 to 4, the sensor head 12 is
Are brazed by the brazing material 14. As described above, the temperature sensor 2 for a cooker according to the present invention uses an insulator having good heat conductivity as a sensor head, and therefore, it has been difficult to bond by welding as in the related art. Therefore, as a result of examining various joining methods, it was concluded that brazing was optimal including airtightness, heat resistance, mechanical strength, and mass productivity.

In the present embodiment, a brazing structure when the temperature sensor 2 for a cooking appliance is used at a high temperature is shown. A tungsten or molybdenum film is formed on a sensor head 12 made of an electrically insulating material having good thermal conductivity such as alumina, and a high-temperature brazing material such as silver, nickel or tantalum is provided between the support 4 and the tungsten or molybdenum film. And so on. Even if the temperature sensor for a cooker having this configuration was used at 250 ° C. or higher, no problem occurred.

Embodiment 4 The sensor head 12 and the support 4 were brazed using a low-temperature brazing material of silver + copper + titanium in the same configuration as in the third embodiment. According to this configuration, the fixing of the sensor head 12 and the support 4 is completed in one step of the brazing step, and a product excellent in mass productivity can be provided.

Embodiment 5 As described in Embodiment 1, the temperature sensor 2 for a cooker is practically provided inside the support body 4 with the radiator 18 and the radiator 18.
Is often provided with a holding mechanism 19 for holding the. This is to make it easy for the sensor head and the object to be heated 3 to be in close contact with each other by the force of the generating member 18.

The bottom surface (pan bottom) of the object to be heated 3 is generally convex in many cases. When the area of the sensor head and the contact area between the sensor head and the bottom surface of the object to be heated 3 are substantially the same, the temperature of the object to be heated 3 can be accurately measured. That is, the smaller the area of the sensor head is, the more the purpose is satisfied. However, when the area of the sensor head is reduced, the distance between the support 4 and the electric terminals 8 of the thermosensitive element 15 and the lead wires connected to the electric terminals 8 is reduced. In such a state, the generating body 1 as shown in FIG.
When the insertion member 8 is inserted, the insulation distance between the generating member 18 and the electric terminal 8 or the like is not sufficiently ensured, and there is a possibility that the generating member 18 and the electric terminal 8 may be electrically short-circuited due to vibration or variation in the manufacturing process. The present embodiment provides a configuration for solving this problem.

In FIG. 3 , the sensor head 12 is brazed so as to cover the central hole of the metal plate 20 processed into a donut shape, and the temperature sensor 7 is provided on the sensor head.
A caulking process is performed between the outer peripheral portion of the metal plate 20 and the separate fitting body 21, and the fitting body 21 is further pressed into the support 4. With this configuration, a sufficient distance between the electric terminal 8 and the generator 18 can be ensured, and the short circuit accident can be prevented. Further, in order to improve the contact with the object 3 to be heated, the surface of the sensor head 12 is preferably formed to have a convex shape protruding from a portion subjected to the caulking process.

In this embodiment, the case where the metal plate 20 has a donut shape has been described. However, any shape having holes in the metal plate 20 may be used as long as the object of this embodiment is achieved. There may be.

Embodiment 6 In FIG. 3 , a sensor head 12 is soldered so as to cover a central hole of a metal plate 20 processed into a donut shape, and a temperature thermosensitive element 7 is provided on the sensor head. Then, the outer peripheral portion of the metal plate 20 and the flange portion of the support 4 are joined by brazing or welding. However, in the case of welding, man-hours are required as described above. With this configuration, the same effect as that of the seventh embodiment can be obtained. The same can be said for the point of projecting the sensor head 12 and the shape of the metal plate 20 as in the case of the seventh embodiment.

Example 7 The same effect was obtained when an electrical insulator such as ceramic was used instead of the metal plate 20 of Example 6 .

[0043]

As described above, according to the temperature sensor for a cooker of the present invention, the following effects can be obtained.

In the temperature sensor for a cooking device of the present invention, a heat conduction promoting film having good heat conduction is provided between a surface in contact with an object to be heated and a temperature-sensitive film or a temperature-sensitive material for detecting the temperature .
And the heat response speed is fast. For this reason, since control according to the temperature of the object to be heated can be performed, there is no cooking failure, and safety and usability are good.

Further, since the sensor head and the support are joined by brazing, the configuration is simple and the production can be easily automated.

Further, it is economical because the brazing material for the brazing can be changed depending on the use of the cooking utensil.

Further, since the sensor head portion is made convex and this sensor head portion is joined to the support through an insulator such as metal or ceramic, the area of the sensor head is reduced, and the temperature-sensitive film or the temperature-sensitive film is formed. It is possible to prevent electrical contact between the electric terminal of the heat-sensitive body and the radiating body provided inside the support. Therefore, it is possible to obtain a safe cooker temperature sensor with high measurement accuracy.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a cooker temperature sensor according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a cooker temperature sensor according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view of a cooker temperature sensor according to Embodiments 3 , 5 , and 6 of the present invention.

FIG. 4 is a sectional view of a cooker temperature sensor according to a third embodiment of the present invention.

FIG. 5 is an external view of a cooking utensil.

FIG. 6 is a sectional view of a conventional temperature sensor for a cooking appliance.

[Explanation of symbols]

 2 Temperature Sensor for Cooker 3 Heated Object 4 Support 11 Electrical Insulator 12 Sensor Head 13 Temperature Sensitive Film 14 Row Material 15 Temperature Sensitive Material 16 Heat Conduction Promoting Film 20 Metal Plate 21 Fitting Body

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shuji Ito 1006 Kazuma Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-57-19525 (JP, A) (58) Investigated Field (Int.Cl. ⁷ , DB name) G01K 1/14 G01K 1/16

Claims (6)

(57) [Claims] 1. A sensor head made of a good thermal conductive electrical insulator having an outer surface in contact with an object to be heated, a support for supporting the sensor head, and a temperature sensor on an inner surface of the sensor head.
Heat-sensitive membrane or become more cooker temperature sensor odor and temperature sensitive body provided in contact with the inner surface of the sensor head
Between the sensor head and the temperature sensing element.
Heat transfer from the sensor head to the thermosensitive body is easily performed.
For cookers with a heat conduction enhancing film
Temperature sensor. 2. A method according to claim 1 Symbol configuration the sensor head made of good heat conductive electrical insulator was subjected row to the metal of the support
Mounting cooker temperature sensor. 3. A sensor head made of an electrical insulator having good thermal conductivity, a tungsten or molybdenum film is formed on a metal support on the sensor head, and brazed to the support using a high-temperature brazing material. The temperature sensor for a cooker according to claim 2 . 4. A cooking appliance temperature sensor according to claim 2, wherein the high heat sensor head comprising a conductive electrical insulator was brazed using a low temperature brazing material of silver + copper + titanium metal support. 5. A sensor head comprising a hole provided in a metal plate and a sensor head attached so as to cover the hole, a fitting body and a support, and an outer peripheral portion of the sensor head and the fitting. The temperature sensor for a cooking appliance according to claim 1 or 2 , wherein a caulking process is performed with the united body, and the fitting body is pressed into the support body. 6. A sensor head comprising a hole provided in a metal plate or an insulating plate and a sensor head mounted so as to cover the hole, and a support, wherein an outer peripheral portion of the sensor head and the support are provided. 3. The temperature sensor for a cooker according to claim 1, wherein the temperature sensor is configured to be attached to a flange of a body.