JPS6131767B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a detection device for detecting an incomplete combustion state of a main burner in an indoor open gas combustion appliance or the like.

There are three types of incomplete combustion patterns in gas combustion equipment, provided that the type and pressure of the supplied gas are normal. These are (1) caused by a drop in the indoor oxygen concentration, (2) caused by a lack of primary air due to dust clogging in the primary air vents of the main burner, and (3) clogged fins in the heat exchanger of the water heater. This is caused by a lack of secondary air.

A pilot burner is already known as a countermeasure against a decrease in oxygen concentration, which detects a decrease in oxygen concentration by utilizing the rise of a flame when the oxygen concentration decreases.
With this alone, incomplete combustion due to lack of primary air in the main burner or lack of secondary air cannot be detected unless the ambient oxygen concentration decreases.

If the fins of the heat exchanger become clogged, a pipe is connected from the top of the heat exchanger combustor to the vicinity of the primary air hole of the oxygen concentration detection pilot burner, and if the fins of the heat exchanger become clogged, the pressure inside the combustion chamber increases. Therefore, there is a method to carry out the detection by transporting the contaminated air in the combustion chamber to the vicinity of the primary air hole of the pilot burner, creating the same conditions as when the oxygen concentration is low. Note that when the fins of the heat exchanger are normal, the pressure in the combustion chamber becomes negative due to the draft force, and contaminated air does not pass through the pipes, which prevents incomplete combustion due to clogging of the primary air holes of the main burner. It has no effect.

There is currently no effective countermeasure against clogging of the primary air holes of the main burner.

Further, in any case, changes in the flame of the main burner can be seen, so a method of measuring changes in the flame using a sensor such as a thermocouple is effective for a single pattern. However, the changes to the above three patterns are different for lift, blow-off, and yellow chip, and are not uniform. Therefore, it can be said that there is no conventional device capable of detecting all three patterns.

The present invention attempts to detect all of the above three patterns of incomplete combustion, and examples thereof will be described below with reference to the drawings.

1 and 2 show the overall configuration of one embodiment. 1 is a Bunsen type main burner, 2 is an incomplete combustion detection device configured as a part of the main burner 1, 3 is a temperature sensing element such as a thermocouple, 4 is an auxiliary air hole,
5 is a nozzle holder, 6 is a nozzle, from which gas is ejected, primary air is sucked, and the main burner 1 is
The flame enters the flame hole 7 and forms a flame. The incomplete combustion detection device 2 is installed so as to occupy a part of this flame section 7. 8 is a gas supply pipe.

3 to 5 are enlarged views of the incomplete combustion detection device 2, in which a circular tube 9 is vertically installed in the main burner 1 so as to occupy a part of the flame hole 7. The circular tube 9 is in close contact with the burner 1, its bottom surface is closed, and only the opening at the upper end and the auxiliary air hole 4 provided on the side surface of the lower end communicate with the outside. The heat sensitive element 3 is located above the flame hole part 7 and is attached halfway to the side surface up to the upper end opening, and detects the temperature of the flame. In this way, the incomplete combustion device 2 includes a circular tube 9 having an auxiliary air hole 4.
It is constructed by attaching a heat-sensitive element 3 to the heat-sensitive element 3. 10 is a heat-sensitive element mounting screw fixed to the circular tube 9, and 11 is a heat-sensitive element holding screw.

This incomplete combustion detection device applies the principle of a so-called separate flame burner. FIG. 6 is a schematic diagram of a separate flame burner. The gas supplied from the nozzle 12 is mixed with air from the primary air hole 13 to form a primary flame 15 at the first flame hole 14 and, at the same time, to form a secondary flame 17 at the second flame hole 16. In order to stabilize the primary flame 15, auxiliary air holes 18 may be provided. In this burner, the primary air hole 13
Or, if contaminated air or low oxygen concentration air enters the auxiliary air hole 18, or if no primary air or auxiliary air enters the primary flame 1.
5 rises to the surface and is formed at the location of the second flame hole 16, overlapping with the secondary flame 17. Therefore, by inserting a heat-sensitive element (not shown) between the first flame hole 14 and the second flame hole 16, the atmospheric oxygen concentration can be reduced and the primary
It is possible to detect incomplete combustion due to clogging of auxiliary air holes.

In the incomplete combustion detection device 2 of the above embodiment, the primary flame is formed in the part located inside the cylinder 9 of the main burner flame hole part 7, the primary air enters from the primary air intake part of the main burner 1, and the gas supply is also It will be supplied from the nozzle 6 of the main burner. Therefore, the incomplete combustion detection device 2 is urgently related to the characteristics of the main burner, such as insufficient absolute oxygen amount in the primary air due to low oxygen concentration, insufficient primary air amount due to clogging of the primary air hole, or insufficient combustion of the heat exchanger. In all three cases described above, such as a lack of absolute oxygen in the primary air due to backflow of contaminated air due to a blockage, the primary flame rises to the surface and the heat-sensitive element 3
It is possible to apply large temperature changes to the area, and detect abnormalities accurately.

Depending on the detected signal, the gas supply to the main burner is stopped or an alarm is issued.

7 and 8 show another embodiment, in which a flame separation burner is attached which takes the gas-air mixture from a part of the mixing chamber 21 of the main burner 1, in which the primary flame , forming a secondary flame. That is, 22 is a mixture pipe led out from a part of the mixing chamber of the main burner 1, and 23 is an outer tube provided at the tip of the mixture pipe 22, which forms a secondary flame (not shown) in the upper part. Reference numeral 24 denotes an inner tube located at the lower part of the outer tube 23, which forms a primary flame (not shown) and is also formed continuously with the gas mixture tube 22. 25 is a heat sensitive element located between the primary flame and the secondary flame. 26 is an auxiliary air hole. The operation is the same as that of the above embodiment, so a description thereof will be omitted.

As described above, according to the present invention, (1) incomplete combustion due to a decrease in the oxygen concentration of indoor air, (2) incomplete combustion due to lack of primary air due to dust clogging in the primary air hole of the main burner, etc. (3) Against all patterns of incomplete combustion, such as incomplete combustion that occurs when the supply of secondary air becomes insufficient due to closure of the exhaust system path due to clogged heat exchanger fins of water heaters, etc. It is adaptable and very practical.

[Brief explanation of the drawing]

Fig. 1 is a side view of an incomplete combustion detection device according to an embodiment of the present invention, Fig. 2 is a top view of the same, Figs. 3 and 4 are enlarged side sectional views of the same device, and Fig. 5 is an enlarged view of the same. 6 is a sectional view showing the principle of a separate flame burner, FIG. 7 is a side view showing another embodiment, and FIG. 8 is a top view of the same. 1... Main burner, 2... Incomplete combustion detection device, 3, 25... Temperature sensing element (thermocouple), 4, 26
...Auxiliary air hole.

Claims (1)

[Claims] 1. A main burner that supplies a mixture of gas fuel and primary air to a flame hole and forms a combustion flame in the flame hole while supplying secondary air; A separate flame burner that burns to form a primary flame in a tube that restricts the supply of secondary air, and forms a secondary flame under the supply of secondary air at an opening at the tip of the tube at a position remote from the primary flame; 1. An incomplete combustion detection device, comprising: a detection element inserted at an intermediate position between a secondary flame and a detection element for detecting a primary flame; and a separate flame burner formed in a part of a main burner. 2. The incomplete combustion detection device according to claim 1, wherein a separate flame burner is formed at the tip of a mixture pipe led out from a part of the mixing chamber of the main burner.