JPH041263B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a safety mechanism for a heat exchanger having a plurality of heat exchangers, such as a bathtub with an instantaneous water heater or a water heater with a reheating function. It is something.

(Prior art) Safety mechanisms in combustion equipment such as bathtubs and water heaters include so-called pilot safety mechanisms using thermocouples that respond to pilot flames, as well as safety mechanisms that prevent carbon monoxide from entering the inner shell of heat exchangers. There is a safety mechanism in which a gas sensor is installed to detect the gas to be detected, and when the gas sensor detects the generation of carbon monoxide due to incomplete combustion, a solenoid valve for supplying fuel gas is closed.

(Problem to be solved by the invention) When applying the above-mentioned safety mechanism to a combustion appliance having multiple heat exchangers, such as a bathtub with an instantaneous water heater or a water heater with a reheating function, conventionally, a gas sensor must be provided for each heat exchanger, which requires a large amount of space and increases costs.

The present invention aims to solve this problem.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a communication system that connects adjacent heat exchangers with their inner shells in a combustion equipment having a plurality of heat exchangers. A passage is formed, and a gas sensor is installed in the communication passage.

Gas sensors use carbon monoxide as the gas to be detected.
In some cases, combustible gas may also be used as the test gas.

(Operation) Carbon monoxide is generated due to incomplete combustion in the burner due to lack of oxygen, and when the inner shell is filled, carbon monoxide also flows into the communication passage. Therefore, incomplete combustion in the burner can be detected by detecting carbon monoxide in this communication passage with a gas sensor,
In this way, safety operations such as closing the solenoid valve for supplying fuel gas can be performed when carbon monoxide of a predetermined concentration or higher is generated. In this case, since the gas sensor is installed in a communication path that communicates the inner shells of adjacent heat exchangers, it is possible to detect carbon monoxide filled in either inner shell, and the gas sensor It is possible to detect the occurrence of incomplete combustion not only when the burners corresponding to the burners are being burned at the same time, but also when only one side is being burned.

In addition to using carbon monoxide as the gas to be detected, gas sensors can also be used to detect flammable gases in some cases. Emissions can also be detected.

(Embodiments) Next, the present invention will be explained with reference to illustrated embodiments.

FIG. 1 shows an example of a combustion device to which the present invention is applied, and this combustion device includes a heat exchanger 1a for hot water supply,
This figure shows a water heater with a reheating function that is equipped with a heat exchanger 1b for reheating. Reference numerals 2a and 2b indicate inner shells of the respective heat exchangers 1a and 1b, and a communication passage 3 is formed between the inner shells 2a and 2b. The communication path 3 can be constructed between appropriate positions of the inner shells 2a and 2b, as shown by a solid line or a two-dot chain line in the figure. In the communication path 3, a gas sensor 4 is installed, which is constructed using an element such as a metal oxide semiconductor that uses carbon monoxide as a gas to be detected. This gas sensor 4 is
It is also possible to use an element that also uses flammable gas as the gas to be detected. Reference symbols 5a and 5b indicate the heat exchanger 1
In the fin portions a and 1b, 6a and 6b are water pipes constituting a part of the hot water supply route and a part of the reheating route, respectively.
7a and 7b are burners provided corresponding to the heat exchangers 1a and 1b, 8 is a common pilot burner, 9a and 9b are fuel gas valves corresponding to each burner, and 10 is a fuel gas main valve. be. Further, reference numeral 11 denotes a control means for controlling the fuel gas main valve 10, and this control means receives the output of the gas sensor 4 and the output of a thermocouple 12 provided corresponding to the pilot burner 8 as control inputs. , the fuel gas main valve 10 is controlled by an abnormal output on at least one side.

In the above configuration, by burning the burner 7a corresponding to the hot water supply heat exchanger 1a on the left side of the figure, the temperature of the clean water passing through the water pipe 6a can be raised to perform hot water supply. Heat exchanger 1b for reheating
By burning the burner 7b corresponding to
Reheating can be performed by raising the temperature of the circulating water in the bathtub passing through the water pipe 6b.

When the burner 7a or 7b causes incomplete combustion due to lack of oxygen during such hot water supply or reheating operations, carbon monoxide is generated and fills the inner shell 2a or 2b, and the carbon monoxide is continuously released. aisle 3
The gas also flows into the interior, and the gas sensor 4 detects this.

When the detection output of the gas sensor is equal to or higher than a predetermined value, the control means 11 generates a control output and closes the fuel gas main valve 10 to cut off the supply of fuel gas, thereby preventing the progress of incomplete combustion. . Further, in the embodiment shown in FIG. 1, the control means 11
This is a so-called system that generates a control output and closes the fuel gas main valve 10 even when the thermoelectromotive force generated by the thermocouple 12 decreases by more than a predetermined value due to misfire or abnormal combustion of the pilot burner 8. Perform pilot safety operations.

In the embodiment shown in FIG. 1, a pilot safety mechanism is also used, but it goes without saying that the present invention can also be applied to so-called direct ignition type combustion equipment that does not have a pilot burner. Furthermore, the first
In the illustrated embodiment, the fuel gas valves 9a and 9b may be open/close valves, proportional control valves, or the like, and their configurations and control operations may be appropriate. Furthermore, as mentioned above, the combustion equipment shown in Fig. 1 represents an embodiment in which the present invention is applied to a water heater with a reheating function, but Fig. 2 shows an example in which the present invention is applied to a bathtub with an instantaneous water heater. This figure shows an example of the above. That is, in FIG. 2, reference numeral 1a is a hot water supply heat exchanger constituting an instantaneous water heater, 1b is a heat exchanger constituting a bath pot, and a communication passage 3 is provided between the respective inner bodies 2a and 2b. A gas sensor 4 is installed in this communication path 3. Further, reference numeral 6a is a water pipe for supplying hot water, and reference numerals 13 and 13' are circulation connection ports for connecting to a bath.
Thus, the present invention can be applied to any appropriate combustion equipment having a plurality of heat exchangers.

(Effects of the Invention) As described above, in a combustion equipment having a plurality of heat exchangers, the present invention configures a communication path between adjacent heat exchangers to communicate their inner bodies, and connects the communication path to the communication path. Since a gas sensor is installed, the common gas sensor can detect carbon monoxide, etc. that is filled in either inner cylinder. In fact, it is possible to detect the occurrence of incomplete combustion even when only one side is being combusted, and the installation space is small, contributing to the downsizing of combustion equipment and reducing costs. be.

[Brief explanation of drawings]

FIG. 1 is a system explanatory diagram showing the overall configuration of one embodiment of the present invention, and FIG. 2 is a perspective view of essential parts of another embodiment of the present invention. Symbols 1a, 1b...Heat exchanger, 2a, 2b...Inner shell, 3...Communication path, 4...Gas sensor, 5a, 5b...
Fin portion, 6a, 6b...water pipe, 7a, 7b...burner, 8...pilot burner, 9a, 9b...fuel gas valve, 10...fuel gas main valve, 11...control means, 1
2...Thermocouple, 13, 13'...Circulation connection port.

Claims (1)

[Claims] 1. In a combustion equipment having a plurality of heat exchangers,
A safety mechanism for combustion equipment, characterized in that a communication path is formed between adjacent heat exchangers to communicate their inner shells, and a gas sensor is installed in the communication path. 2. The gas sensor according to item 1 is a safety mechanism for combustion equipment, characterized in that the gas to be detected is carbon monoxide.