JPH08297058A - Temperature sensor for gas heater - Google Patents

Abstract

PURPOSE: To obtain a bimetal type temperature sensor exhibiting quick response while suppressing malfunction. CONSTITUTION: A cap 14 at the forward end of a head part 12 is integrated with the housing 15 at a sensor part 17 by welding, for example, in order to enhance the thermal conductivity. A step part 28 is provided at the lower part of the head part 12 and a flange part 29, to be engaged therewith, is provided at a post part 11. A guide 30 made of a thermal insulation material is applied over the flange part 29 while projecting outward and a spring 13 is mounted thereon in order to urge the head part 12 upward. When a pan, etc., is not placed, heat escapes from the head part 12 to the post part 11 touching it and when a pan, etc., is placed, the head part 12 sinks and isolated thermally from the post part 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas stove temperature sensor which is installed in a gas stove, detects the temperature of a pan or the like, and automatically shuts off the gas when overheated.

[0002]

2. Description of the Related Art Conventionally, as this type of temperature sensor,
As a temperature sensitive element, a thermistor is used. This temperature sensor requires a controller circuit, complicates the entire system, and is unsatisfactory in terms of reliability and cost.

[0003]

As a countermeasure against this, it is conceivable to use a bimetal as the temperature sensitive element. The bimetal can directly drive a large-capacity switch, omits a controller circuit, is simplified, and is inexpensive and highly reliable.

However, a bimetal type temperature sensor has not been put to practical use so far. The first reason is that the response speed is slow. A mechanical stroke for opening and closing the contacts requires a certain amount of stroke, which increases the volume of the bimetal element, that is, the heat capacity. Second
The reason is that it is easy to cause a malfunction when a pot etc. is not placed. This type of temperature sensor is usually provided in the center of the burner, and must not shut off gas when a pot or the like is not placed. Since the bimetal type temperature sensor becomes large as described above, when the pan or the like is not placed, the surroundings are likely to be exposed to the flame of the gas and unnecessarily block the gas.

An object of the present invention is to solve these problems and to put into practical use a bimetal type temperature sensor which has a high response speed and is less likely to malfunction.

[0006]

The present invention comprises two solutions. The first means relates to the configuration of the tip portion. That is, for a gas stove that includes a post portion fixed to the stove, and a head portion that has a built-in sensor portion at the tip, covers the tip of the post portion, is biased upward by a spring, and is pressed against a pan or the like. In the temperature sensor, the head portion includes a cap that constitutes the tip portion of the head portion and is in contact with a pot, and a housing that is integrally formed on the inner surface of the cap by welding or the like and that houses the bimetal element that constitutes the sensor portion. A temperature sensor for a gas stove characterized by having.

The first means includes a post portion fixed to the stove and a sensor portion at the tip, and the tip portion of the post portion is covered with the post portion and is biased upward by a spring and pushed to a pot or the like. In the method of manufacturing a temperature sensor for a gas stove consisting of a head part to be applied, a housing is integrally formed by welding or the like on the inner surface of the cap that constitutes the tip part of the head part and is in contact with a pan, etc. A method of manufacturing a temperature sensor for a gas stove is characterized in that a bimetal element or the like is assembled to complete a sensor part, and further other parts are assembled to complete the whole.

The second means relates to the structure of the support column. That is, for a gas stove that includes a post portion fixed to the stove, and a head portion that has a built-in sensor portion at the tip, covers the tip of the post portion, is biased upward by a spring, and is pressed against a pan or the like. In the temperature sensor, the lower part of the head part has a substantially cylindrical shape, and has a step part projecting inward at the lower end, and the upper end part of the post part has a flange part projecting outward and engaging with the step part. , A guide made of a heat insulating material protruding outward from the flange is placed on the flange, a spring for biasing the head is placed on the guide, and the head is
The head part and the post part are thermally cut when the guide part moves up and down and descends, and the head part and the post part are thermally connected by contacting the collar part and the step part when rising. A temperature sensor for a gas stove characterized by the above.

The above first and second means can be used together. That is, for a gas stove that includes a post portion fixed to the stove, and a head portion that has a built-in sensor portion at the tip, covers the tip of the post portion, is biased upward by a spring, and is pressed against a pan or the like. In the temperature sensor, the head portion includes a cap that constitutes the tip portion of the head portion and is in contact with a pot, and a housing that is integrally formed on the inner surface of the cap by welding or the like and that houses the bimetal element that constitutes the sensor portion. Have, and more. The lower part of the head part has a substantially cylindrical shape and has a step part projecting inward at the lower end, and the upper end part of the post part has a flange part projecting outward, and on this flange part, from this flange part. A guide made of heat insulating material protruding outward is placed,
A spring for urging the head part is placed on this guide, and the lower part of the head part is guided by the guide to ascend and descend, and when descending, the head part and post part are thermally cut, and when ascending, the collar part and step part. The present invention also includes a temperature sensor for a gas stove, which is characterized in that the head portion and the post portion are thermally connected by contacting each other.

[0010]

The first means is to improve the thermal conductivity to the bimetal and the response speed by integrating the housing of the sensor part and the head part. The conventional temperature sensor has a structure in which a sensor part is formed in advance in a housing and is pushed and held in a separately formed head part, and the sensor part simply contacts the tip of the head part.

The second means is to put a pot or the like on it.
Even if the burner flame touches the head part by contacting the head part with the post part, the heat is released to the post part so that the sensor part does not malfunction due to this heat. The part is thermally separated from the post part so that the sensor part operates reliably.

[0012]

EXAMPLES Hereinafter, examples illustrating the present invention will be specifically described.

The gas stove temperature sensor 10 comprises a lower post portion 11 and an upper head portion 12. The post portion 11 is attached to a stove (not shown),
It is usually designed to stand upright in the center of the burner. The head portion 12 covers the tip of the post portion 11 and is urged upward by a spring 13, and when a pot (not shown) or the like is placed, the tip surface is pressed against the lower surface of the pot or the like.

A substantially inverted cup-shaped cap 14 is provided at the tip of the post portion 12, and a housing 15 is integrally formed on the inner surface of the cap 14 by welding, welding or the like. The cap 14 and the housing 15 are made of a good heat conductive material such as metal.

In the housing 15, the bimetal element 1 is provided.
6 is accommodated to form the sensor unit 17.

As shown in FIG. 2, the sensor section 17 has the following structure. The bimetal element 16 has a dish shape and is convex upward due to temperature change (illustrated).
And a convex state (not shown) downwardly deformed, and the peripheral end portion is supported by the convex strip 18 formed on the bottom portion of the housing 15. The upper end of a rod 19 abuts on the central portion of the bimetal element 16, and the rod 19 can be moved up and down by being guided by a guide member 20 fitted and held in the housing 15. The lower end of the rod 19 contacts the elastic plate 21 and is biased upward. A base end of the elastic plate 21 is supported by a terminal 23 held by a lid member 22 of the housing 15, and a movable contact 24 is provided at a tip thereof, and the movable contact 24 is another terminal 25 held by the lid member 22. Facing the fixed contact 26 at the tip,
When pushed by the rod 19, it comes into contact with this. Therefore, when the temperature of the sensor unit 17 is low, the movable contact 24 is separated from the fixed contact 26 to be in the OFF state as shown in the figure, and when the temperature is high, the bimetal element 16 is inverted and the rod 19 pushes the elastic plate 21. Moving contact 24
Comes into contact with the fixed contact 26 and is turned on.

In manufacturing the sensor section 17, first, as shown in FIG.
Are integrally formed by welding or the like, and then the bimetal element 16 and the like are assembled in this order. After that, the temperature sensor as a whole is completed by assembling other parts described later.

A substantially cylindrical cover 27 is attached to the cap 14 by welding, press fitting, or the like, and a step portion 28 projecting inward is formed at the lower end of the cover 27.

A flange portion 29 is formed at the upper end of the post portion 11 so as to project outward. A guide 30 is provided on the collar portion 29.
Will be posted. The guide 30 has a short tubular shape with a large diameter in the upper portion, and is made of a heat insulating material such as ceramic or heat resistant plastic. When the cover and the post are made of a material having an extremely high thermal conductivity such as brass, stainless steel having a smaller thermal conductivity than these can be used as the heat insulating material. The spring 1 is provided between the guide portion 30 and the cap 14.
3 is interposed.

The upper portion of the guide 30 has a diameter larger than that of the collar portion 29, and the cover 27 covers the post portion 11 so that the inner periphery thereof is guided to the outer periphery of the guide 30 without touching the collar portion 29. The step portion 28 is located below the collar portion 29,
It is arranged so as to be engaged and prevented from coming off.

Wires 31 and 32 are connected to the terminals 23 and 25 of the sensor section 17, respectively, and the post section 11
Drawn from.

The temperature sensor 10 is constructed as described above and is used by fixing the post portion 11 to a gas stove (not shown) and standing upright at the center of the burner.
It works as follows.

When a pot or the like is placed on the burner, the head portion 12
The tip of the cap 14 at the tip contacts the bottom of the pot,
Pressed by 3. Therefore, the temperature of the pot or the like is detected by the sensor unit 17. Also, as shown in FIG.
Since the cover 27 is pushed down and only contacts the post portion 11 via the guide 30 made of a heat insulating material, the heat of the pot or the like does not escape to the post portion 11 and the operation of the sensor portion 17 is maintained well. It

When the pot or the like is not placed on the burner, the head portion 12 rises and the step portion 28 of the cover 27 contacts the flange portion 29 of the post portion 11 as shown in FIG. Even if the burner is heated by being exposed to the flame, the heat is released to the post portion 11, and the sensor portion 17 is prevented from detecting the overheat and shutting off the gas.

In the above-described embodiment, the plate-shaped bimetal element of the sensor portion is used, and the convex strips of the housing support the bimetal element. However, it goes without saying that other configurations may be used. For example, the housing 1 shown in FIG.
It is also possible to have a bottomless shape, such as 5 ', which supports the dish-shaped bimetal element at the edge 18'. The point is that the housing is integrated with the cap so that the thermal conductivity is good.

[0025]

According to the temperature sensor of the present invention, according to the first means, the cap of the head portion and the housing of the sensor portion are integrally formed, so that the conventional sensor portion is simply pressed against the cap. Compared with the above, the thermal conductivity of this portion is remarkably good, and even if a bimetal having a large heat capacity is used, a sufficiently fast response can be obtained.

According to the second means, the head portion and the post portion are in contact with each other when the pot or the like is not placed on the burner. Even in the case of being exposed to a flame and being heated, heat is prevented from escaping to the post portion, causing the sensor portion to operate unnecessarily and shutting off gas. Further, when a pot or the like is placed, the head portion contacts the post portion via the guide made of a heat insulating material so that heat does not escape to the post portion, so that there is no inconvenience in the operation of the sensor portion.

By using the first and second means in combination, the above effects can be obtained together, and the gas stove temperature sensor using a bimetal element can be made practical.

[Brief description of drawings]

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

FIG. 2 is an enlarged cross-sectional view of a temperature sensor portion of the same example.

FIG. 3 is a sectional view of a part in which a cap and a housing used in the same example are integrally formed.

FIG. 4 is an enlarged cross-sectional view of a connection portion between a post portion and a head portion in the same example, showing a case where a pot or the like is not placed.

FIG. 5 is an enlarged cross-sectional view of a connection portion between the post portion and the head portion of the same example, showing a case where a pot or the like is placed.

FIG. 6 is a cross-sectional view of another embodiment of a component in which a cap and a housing are integrally formed.

[Explanation of symbols]

10 ... Temperature sensor for gas stove, 11 ... Post part, 12
... head part, 13 ... spring, 14 ... cap, 15, 1
5 '... Housing, 16 ... Pimetal element, 17 ... Sensor part, 27 ... Cover, 28 ... Step part, 29 ... Collar part, 30 ...
guide.

Claims (4)

[Claims] 1. A post portion fixed to a stove,
In a gas stove temperature sensor that has a built-in sensor part at the tip, covers the tip of the post part, is biased upward by a spring, and is pressed against a pan etc., the head part is the tip part of the head part. A temperature sensor for a gas stove, comprising: a cap that is in contact with a pan or the like, and a housing that is integrally formed on the inner surface of the cap by welding or the like and that houses a bimetal element that constitutes a sensor unit. 2. A post portion fixed to the stove,
In the method of manufacturing a temperature sensor for a gas stove, which comprises a sensor part built in at the tip, which covers the tip of the post part, is biased downward by a spring, and is pressed against a pot, etc., the tip part of the head part is configured. A housing is integrally formed by welding etc. on the inner surface of the cap that is in contact with a saucepan, and then a bimetal element is assembled inside the housing to complete the sensor part. A method of manufacturing a temperature sensor for a gas stove, which is characterized by completing. 3. A post portion fixed to the stove,
In the gas stove temperature sensor, which has a built-in sensor at the tip, covers the tip of the post, is urged upward by a spring, and is pressed against a pot, etc. , A step portion projecting to the inner circumference at the lower end, and an upper end portion of the post portion having a flange portion projecting outward and engaging with the step portion, on the collar portion, outward from the collar portion. A guide made of a heat insulating material is placed on the guide, and a spring for urging the head portion is placed on the guide. When the head portion is guided by the guide to move up and down and descend, the head portion and the post portion are thermally A temperature sensor for a gas stove, characterized in that the head portion and the post portion are thermally connected to each other when the collar portion and the step portion are in contact with each other when being cut and raised. 4. A post portion fixed to the stove,
In a gas stove temperature sensor that has a built-in sensor part at the tip, covers the tip of the post part, is biased upward by a spring, and is pressed against a pan etc., the head part is the tip part of the head part. And a housing that is integrally formed on the inner surface of this cap by welding or the like and that accommodates the bimetal element that constitutes the sensor section, and the lower part of the head section has a substantially tubular shape. Has a step portion projecting to the inner circumference at the lower end, and an upper end portion of the post portion having a flange portion projecting outward and engaging with the step portion, and on the collar portion, outside the collar portion. A guide made of a heat insulating material is placed on the guide, and a spring for urging the head is placed on the guide. When the head is guided by the guide and moves up and down, the head and the post are heated. When it is cut off and rises, Stovetop temperature sensor, wherein the head portion and the post portion part is in contact is adapted to be thermally connected.