JP2001132941A - Overheat preventer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a control circuit for simplifying the structure and reducing the manufacturing cost, and a bimetal switch type overheat preventive sensor using no battery. SOLUTION: An overheat preventive sensor 2 provided in the center of a burner mounted on a gas cooking stove and attached tightly to the bottom of a pan. A bimetal switch 3, a thermocouple 4 and a safety valve 5 provided in a gas flow channel are connected in series through a wire 6 to constitute an electrical closed circuit. A terminal 19 of the bimetal switch 3 is connected with the wire 6 through a shaft 8 sliding on a holder 7. In such an overheat preventer, lower end part of the holder 7 is connected with the shaft 8 through a tensile spring 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an overheat prevention device for preventing a fire by tempura oil and an abnormal temperature rise.

[0002]

2. Description of the Related Art A conventional general overheat prevention device is often a fire caused by overheating of tempura oil in a domestic fire. To prevent this, an overheat prevention device is provided at the center of a stove burner of a gas stove. The temperature is detected and the gas is shut off before it rises to the temperature at which the oil ignites.

In this method, a thermistor is conventionally used in the temperature detecting section of the overheat prevention device, and when the oil temperature rises to a high temperature unsuitable for cooking, the gas is shut off.

In recent years, a method using a control circuit and a bimetal switch that does not use a dry battery is generally known for the purpose of simplifying the configuration and reducing the manufacturing cost.

(See, for example, JP-A-8-297058)

[0006]

However, in the conventional case, a stove provided with an overheat prevention sensor is provided with a through hole at the center thereof to dispose the overheat prevention sensor.

In general, a stove burner equipped with a sensor is not provided with an internal flame opening so as not to cause a malfunction such as premature disconnection of the sensor.

For this reason, during the cooking, the flame hits the bottom of the pot only from the outer periphery of the burner, so that the flame does not hit the center of the pot, which may cause uneven heating.

In recent years, in order to reduce the overheating unevenness, the outer diameter of the burner has been reduced, and the flame angle has been improved so that the flame gushes upward and hits the center of the pot bottom more.

Accordingly, the diameter of the overheat prevention sensor has been reduced.

A sensor using a thermistor for the temperature detecting section has been relatively easily miniaturized because the thermistor itself is originally small.

On the other hand, in a sensor using a bimetal switch, the size of the bimetal, contacts, terminals, and the like constituting the bimetal switch can be reduced somewhat.

However, since the thermocouple and the safety valve provided in the gas flow path use a minute current circuit in which the safety valve is connected in series, the electric wire connecting the bimetal switch to the safety valve and the thermocouple has a current loss. To prevent
It is necessary to use a large cross-sectional area, that is, a thick electric wire.

[0014] For this reason, the connection portion with the terminal of the bimetal switch is in a state where there is not enough space for connecting a thick electric wire.

Further, since a spring for urging the sensor upward is disposed so as to enclose the connecting portion, a predetermined distance is provided between the connecting portion and the spring so that the sensor can smoothly slide up and down. Required. For this reason, the diameter of the sensor cannot be reduced, and there has been a problem that the burner outer diameter cannot be reduced as a measure for preventing overheating unevenness.

[0016]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and comprises an overheat prevention sensor provided at the center of a burner mounted on a gas stove and closely attached to the bottom of a pot. The overheat prevention sensor has a bimetal switch, a thermocouple, and a safety valve provided in a gas flow path connected in series by an electric wire to form an electrically closed circuit.The terminal of the bimetal switch and the electric wire communicate with each other through a shaft and are connected. In the overheat prevention device, the shaft is slidable with the holder, and the lower end of the holder and the shaft are connected by a tension spring.

Further, the tension spring is connected at a predetermined distance L from the lower end of the holder.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention provides an overheat prevention sensor provided at the center of a burner mounted on a gas stove or the like and closely attached to the bottom of a pan, and the overheat prevention sensor is provided in a bimetal switch, a thermocouple, and a gas flow path. The safety valve is connected in series with an electric wire to form an electrically closed circuit, and the terminal of the bimetal switch and the electric wire are connected to each other through a shaft, and the shaft is slidably connected to a holder. In the prevention device, the lower end of the holder and the shaft are connected by a tension spring, so that there is no spring around the connection between the terminal and the wire, so the distance between the holder and the connection can be reduced. Thus, the diameter of the sensor can be reduced.

As a result, it is possible to reduce the outer diameter of the burner.

[0020]

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

In FIG. 1, reference numeral 1 denotes a burner mounted on a gas stove or the like.
Is installed.

The structure of the overheat prevention sensor 2 includes a bimetal switch 3 which is a heat sensing means, a holder 7, a shaft 8, and the like.

A tension spring 9 is provided at the lower end of the holder 7.
Are attached to the connection part 23.

The overheat prevention sensor 2 can move up and down via a shaft 8 and a tension spring 9.

The tension spring 9 is connected to the shaft 8 at a certain distance L from the lower end of the holder 7.
An electric wire 6 connected to a terminal 19 of the bimetal switch 3 communicates with the shaft 8 and is connected to one end of a thermocouple 4 and one end of a safety valve 5 provided in a gas flow path.

The thermocouple 4 is further connected to another end of the safety valve 5 via an electric wire 6.

The structure of the bimetal switch 3 comprises a housing 10, a support 11, a contact 12, and a piston 13.
In addition, a substantially dish-shaped bimetal 1 that inverts at a constant temperature.
4 are arranged.

Reference numeral 15 denotes a metal fitting for mounting the overheat prevention sensor 2, and the overheat prevention sensor 2 is fixed so as to have a certain protrusion dimension H from the length 16.

Reference numeral 17 denotes a burner flame.

Reference numeral 21 denotes a pot, and 22 denotes a food.

When the stove is used, when ignited, the thermocouple 4 is heated, and a thermoelectromotive voltage is generated in a circuit composed of the bimetal switch 3 and the safety valve 5, the safety valve 5 is held, and the combustion of the stove continues. In cooking, when a pot or the like is placed on the goto 16, the overheat prevention sensor 2 moves downward through the shaft 8, but is urged upward by the tension spring 9 connected to the lower end of the holder 7 and the shaft 8. The bimetal switch 3 contacts the bottom of the pan 21 and transmits the temperature of the pan bottom to the bimetal 14.

Further, even if boiling occurs during cooking, the connecting position of the tension spring 9 is located at a fixed distance L from the lower end of the holder 7, so that the boiling does not penetrate and the sliding failure does not occur. Don't worry.

On the other hand, according to the present invention, since the compression spring 18 as shown in FIG. 4 does not exist near the terminal 19 of the bimetal switch 3 and the connection 23 of the electric wire 6, the distance between the holder 7 and the connection 23 is made as small as possible. It is possible to shrink.

As a result, as shown in FIG. 3, the diameter d of the overheat prevention sensor 2 can be made as small as possible, and the outer diameter D of the burner 1 can be made small.

[0035]

As described above, according to the present invention, it is possible to reduce the diameter of the sensor even in the overheat prevention device using the bimetal switch, and accordingly, the outer diameter of the burner is reduced. Therefore, the flame from the burner can be made closer to the center of the bottom of the pot, and a highly efficient burner with less overheating unevenness can be provided.

Further, by arranging the emission of the flame in the central portion, it is possible to prevent ignition of the clothes which may occur during cooking.

This leads to the spread of overheat prevention devices using a bimetal, which is a system that does not use a control circuit and a dry cell, for the purpose of simplifying the structure and reducing the manufacturing cost.

[Brief description of the drawings]

FIG. 1 is a main part configuration diagram of an overheat prevention device showing one embodiment of the present invention.

FIG. 2 is a main part configuration diagram of the overheat prevention device according to an embodiment of the present invention when no load is applied.

FIG. 3 is a perspective view of an overheat prevention device showing one embodiment of the present invention.

FIG. 4 is a main part configuration diagram of an overheat prevention device showing one embodiment of the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Burner 2 Overheat prevention sensor 3 Bimetal switch 4 Thermocouple 5 Safety valve 6 Electric wire 7 Holder 8 Shaft 9 Extension spring 19 Terminal 23 Connection part

Claims (2)

[Claims] An overheat prevention sensor (2) provided at the center of a burner (1) mounted on a gas stove or the like and closely attached to the bottom of a pan, and the overheat prevention sensor (2) comprises a bimetal switch (3) and a thermocouple (2). 4) and a safety valve (5) provided in the gas flow path are connected in series by a wire (6) to form an electrically closed circuit, and the terminal (19) of the bimetal switch (3) and the wire (6) are connected to each other. Is connected to and connected to a shaft (8), wherein the shaft (8) is slidable with the holder (7). Is a tension spring (9)
An overheat prevention device, characterized by being connected by: 2. The tension spring (9) comprises a holder (7).
2. The overheat prevention device according to claim 1, wherein the device is connected with a predetermined distance L from a lower end of the device.