JPH0740838Y2 - Overheat prevention device for combustion equipment and heat detection sensor used in the device - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention is directed to an abnormal overheating that may cause a fire in a heating part such as a combustion chamber or a heat exchanger in a combustion equipment such as a gas water heater or an oil combustor. TECHNICAL FIELD The present invention relates to an overheat prevention device for a combustion device that immediately stops the supply of fuel such as gas when it is cracked or punctured due to damage, and a heat detection sensor used in the device.

[Conventional technology]

As an overheat preventing device in a conventional combustion device, for example, as shown in FIG. 8, a glass tube or ceramic tube type thermal fuse 4'as a heat detecting sensor.
The temperature fuse 4'is attached to the combustion chamber 1'of the combustion equipment or the heat exchanger 2'or the like on the outer rear surface of the heating part, and the connection terminal of the temperature fuse 4'is a thermocouple type electromagnetic safety valve circuit. It is general to connect to the above to prevent overheating, and a plurality of thermal fuses provided in a scattered manner outside the heating portion such as a combustion chamber or a heat exchanger has also been proposed.

[Problems to be solved by the device]

For combustion equipment that is frequently used, such as commercial gas water heaters, the heating part of the combustion chamber or heat exchanger may overheat abnormally during continuous use for a long time, causing cracks and punctures. May occur, and hot exhaust gas may leak from the cracks and holes to burn the outer casing and cause a fire. There is a problem that the thermal fuse does not operate at all if the location such as a crack due to abnormal overheating, a hole such as a hole is far from the thermal fuse, which is simply attached to the outer rear surface of the heating portion of the container, etc. In the case where multiple temperature fuses are scattered outside the heating part such as the combustion chamber and heat exchanger, many temperature fuses are mounted outside the heating part such as the combustion chamber and heat exchanger. Due to abnormal overheating Since the cracks, holes, etc. are often localized, the thermal fuse does not always detect it and operate reliably, but only complements the above-mentioned drawbacks even if one thermal fuse is attached. It is not possible to deal with cracks, holes, etc. at unspecified places, and since it is necessary to attach multiple temperature fuses to multiple places outside the heating part such as the combustion chamber or heat exchanger, wiring and assembly. There is a problem in that not only the workability is significantly deteriorated, but also the cost is increased because the work such as the above requires a great deal of labor and technology.

The present invention has been made in view of such problems of the conventional technology,
Of overheating prevention device for combustion equipment and a heat detection sensor used for the device, which can quickly and reliably operate regardless of where cracks, holes, etc. due to abnormal overheating are located in the combustion chamber and the heating part such as a heat exchanger. It is intended to be provided.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the invention of claim 1 of the present invention is such that the outside of the combustion chamber of the combustion equipment and the heat exchange equipment is electrically conductive and is fused at a preset temperature. A series of long fuse members made of metal or the like are evenly arranged in each part with an arbitrary shape, and the long fuse members are incorporated into a combustion control circuit. When the long fuse members detect abnormal overheating and melt down, fuel The invention of claim 2 is characterized in that the long fuse member is a series of linear bodies, and the invention of claim 3 is
The long fuse member is formed as a series of strips, and the invention of claim 4 is characterized in that the long fuse member is evenly attached to one side of a base material having rigidity and has an arbitrary shape and the other parts of the base material. A metal foil such as aluminum foil is attached to the side to form a sheet,
Is a heat detection sensor in which a long fuse member is evenly attached to a metal plate in an arbitrary shape to form a sheet.

[Action]

In the device according to the first aspect of the present invention having the above-mentioned structure, a series of long fuse members made of metal or the like, which is coated with an insulating material and has a conductivity and melts at a preset temperature, are provided in the combustion chamber. Since it is installed outside the heat exchanger, there is no short circuit between the fuse members, and there is no variation in operating temperature due to surface oxidation after a long period of time. When it occurs in the chamber, heat exchanger, etc., a series of long fuse members immediately sense it and blow it. Therefore, since the long fuse member is incorporated in the combustion control circuit, when the long fuse member is blown, the power supply to the combustion control circuit is cut off, the fuel control valve is closed, and the fuel supply is stopped. In addition, since the long fuse members are arranged in each part in an arbitrary shape and evenly arranged, overheat can be reliably detected at an unspecified local position.

In the invention according to claim 2, the long fuse member is a series of covered electric wire-like linear members, and in the invention according to claim 3, a plate body punched into an arbitrary shape is provided with an insulating coating. Since the belt-shaped member is used, it is easy to dispose the combustion chamber, the heat exchanger and the like outside, and moreover, the heat can be detected reliably.

Further, in the invention according to claim 4, the long fuse member covered with the insulating material is attached to one side of the substrate having rigidity, and the other side is attached with a metal foil such as an aluminum foil to form a sheet. When the metal foil is installed on the side of a heating unit such as a combustion chamber of a combustion device, the metal foil reflects heat and has a heat insulating effect, so that it is not necessary to provide a special heat insulating means. The invention according to claim 5 has the same operation as the invention according to claim 4, because a long fuse member covered with an insulating material is attached to a metal plate to form a sheet.

〔Example〕

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

1 and 2 show an example in which the overheat prevention device of the present invention is applied to a wall-mounted forced air supply type gas water heater, in which 1 is a combustion chamber of the gas water heater, and a water supply pipe 7 is provided on the outer surface thereof. The heat exchanger 2 is spirally wound and connected to the inlet side of the endothermic tube 8 of the heat exchanger 2 provided at the upper part, and a gas burner 9 is installed at the lower part to heat the heat exchanger 2 by the gas burner 9 2 endothermic tubes 8
The cold water flowing through is heated and heated to supply hot water from a hot water supply pipe 10 connected to the outlet side of the heat absorption pipe 8 to a sink or a bath. Further, an air supply chamber 11 is hermetically connected to a lower portion of the combustion chamber 1, a duct 13 of an air supply fan 12 is connected and opened at a bottom portion of the air supply chamber 11, and a bottom portion of the air supply chamber 11 and the gas burner are connected. 9
A perforated baffle plate 14 is provided between the air conditioner and the air supply fan 12 so that the air from the air supply fan 12 is rectified by the perforated baffle plate 14 and forcibly supplied as the air for combustion of the gas burner 9.

Reference numeral 4 denotes a series of long fuse members made of a low temperature molten metal or the like which has conductivity and melts at a preset temperature.
To form an electric wire (see FIG. 4) or a strip plate (see FIG. 5). The long fuse member 4 is bent outside of the combustion chamber 1 and the heat exchanger 2 in an arbitrary shape and evenly arranged at each part, and both ends thereof are connected to a combustion control circuit or the like with lead wires.
The long fuse member 4 is connected via 15 and is incorporated in a combustion control circuit or the like. As the low-temperature molten metal, for example, lead, tin, an alloy of tin and lead, or the like is used, and the set temperature (melting point) thereof is, for example, a safe temperature of about 120 ° C to 200 ° C. In addition, as shown in FIG. 3, the series of long fuse members 4 are bent in a meandering shape and evenly arranged over the entire area outside the combustion chamber 1 and the heat exchanger 2, or in any other shape. You are free to bend,
The arrangement may be provided on the rear surface and both sides of the embodiment, only on the rear surface or only on the front surface, and further on the entire peripheral surface.

In the figure, 16 is an exhaust tube, 17 is an outer case, 18 is a heat insulating material provided inside the outer case 17, and 19 is a supply air intake provided in the outer case 17.

In the above-mentioned configuration, even if cracks or the like occur at any position outside the combustion chamber 1 and the heat exchanger 2 due to abnormal overheating that may cause a fire, for example, the combustion chamber 1 and the heat exchanger are bent in a meandering shape. 2, the corresponding portion of the series of long fuse members 4 arranged evenly over the entire area immediately senses this and melts the fuse, so that the fuel control valve is closed and the fuel control valve is closed. The supply is cut off for safety.

6 and 7 show a heat detecting sensor formed in a sheet shape, for example, a base material 5'having rigidity such as a cardboard.
The long fuse member 4 is evenly attached to the surface of one side in a meandering shape or any other shape, and the metal foil 5 such as aluminum foil is attached to the other side of the base material 5 '. Sixth
(See the drawing), the long fuse member 4 is evenly attached to each surface of a metal plate such as a color steel plate in a meandering or other arbitrary shape.

The sheet-like heat detection sensor described above is bent into, for example, a U-shape to form a combustion chamber 1, a heating portion such as the heat exchanger 2, and the outer case 17.
The long fuse member 4 of the seat is inserted and installed on the rear surface and both side surfaces of the heating section by incorporating it into a combustion control circuit such as a thermocouple type electromagnetic safety valve circuit, and a rear section of a heating section due to abnormal overheating that may cause a fire. And, even if cracks, holes, etc. occur at any position on both sides, the corresponding portion of the long fuse member 4 having a meandering shape or an arbitrary shape and arranged evenly in each part immediately senses this and melts and burns. The control circuit operates, the safety valve is closed, and the gas supply is stopped to ensure safety.

[Effects of the Invention] The invention according to claim 1 of the present invention is directed to a series of long fuse members coated with an insulating material even if cracks, perforations, etc. occur due to abnormal overheating in the combustion chamber and heat exchanger. Since the relevant part immediately detects this and melts it off and cuts off the power supply to the combustion control circuit etc. to close the fuel control valve and stop the fuel supply,
When a crack or the like occurs due to abnormal overheating that is dangerous for a fire, it operates quickly and surely to prevent the occurrence of a fire, so that it is possible to improve the safety of a hot water supply for business use, which is particularly frequently used. Further, since the long fuse member is covered with the insulating material, the fuse members are not short-circuited with each other, and the initial quality can be maintained without deterioration due to surface oxidation even after a long time elapses. There is no variation. Therefore, stable overheat detection can always be performed. Further, the work of wiring and assembling is extremely simple, so that the workability is improved and the cost is reduced.

According to the second aspect of the invention, since the long fuse member is formed of a series of wire-shaped linear members, it is easy to dispose the combustion chamber and the heat exchanger outside, and the heat can be detected reliably. The cost is low, and since the long fuse member is a series of strip-shaped members in the invention according to claim 3, it is easy to dispose the combustion chamber and the heat exchanger to the outside, and the heat detection is reliable. Yes, and the cost is low.

According to a fourth aspect of the present invention, a long fuse member covered with an insulating material is attached to one surface of a base material having rigidity, and a metal foil such as an aluminum foil is attached to the other side of the base material. When the metal foil side is installed as the heating part side of the combustion device, the metal foil reflects heat and has a heat insulating effect, so that it is not necessary to provide a special heat insulating means. In addition, the long fuse member has an arbitrary shape and is evenly arranged in each part, and
Since the whole is formed into a sheet shape, overheat can be reliably detected at an unspecified local position, and it can be easily attached to and removed from the combustion equipment, and the heat detection sensor can be replaced easily. According to the invention of claim 5, a long fuse member covered with an insulating material is attached to the surface of a metal plate to form a sheet, so that in addition to the same heat insulating effect as the invention of claim 4, a combustion device is also provided. This is convenient because no special mounting member is required when the sensor is mounted on.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a heating prevention device of the present invention, FIG. 2 is a sectional view taken along line XX of FIG. 1, FIG. 3 is a front view of a fuse member, and FIG. FIG. 5 is an enlarged cross-sectional view taken along the line YY in FIG. 5, and FIG. 5 is the same cross-sectional view with different cross-sectional shapes. Further, FIGS. 6 and 7 are sectional views showing an embodiment in the case where the heat detecting sensor is in the form of a sheet, and FIG. 8 is a sectional view of a conventional example. 1 ... Combustion chamber, 2 ... Heat exchanger, 3 ... Insulating material, 4 ... Long fuse member, 5 ... Metal foil, 5 '... Base material, 6 ... Metal plate.

Claims (5)

[Scope of utility model registration request] 1. A combustion chamber (1) and a heat exchanger (2) of a combustion device.
A series of long fuse members (4) made of metal or the like which is electrically conductive and which is coated with an insulating material (3) and which melts at a preset temperature are evenly arranged with arbitrary shapes. An overheat prevention device for a combustion device, characterized in that the long fuse member (4) is incorporated into a combustion control circuit, and when the long fuse member (4) detects abnormal overheat and melts, the fuel is cut off. 2. A heat detecting sensor for a combustion device, wherein the long fuse member (4) according to claim 1 is used as a series of linear members. 3. A heat detection sensor for a combustion device, wherein the long fuse member (4) according to claim 1 is formed into a series of strips. 4. A long fuse member (4) is evenly attached to one side of a rigid base material having an arbitrary shape and a metal foil such as an aluminum foil is attached to the other side of the base material. The heat detection sensor for a combustion device according to claim 1, wherein the heat detection sensor is formed in a sheet shape. 5. The heat detection sensor for a combustion device according to claim 1, wherein the long fuse member (4) is evenly attached to a metal plate (6) in an arbitrary shape to form a sheet. .