JPH0351627Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a combustion device with an exhaust stack that prevents the generation of abnormal resonance noise in the exhaust stack.

(Prior Art) A premix burner is equipped with a fan that supplies all of the combustion air as primary air, and a combustion shell that surrounds the combustion surface of the burner. 2. Description of the Related Art Combustion devices are known that communicate with the outside and have a combustion barrel or other wall surface facing the root opening end of the exhaust stack.

(Problem to be solved by the invention) The fire vibrates at a specific frequency due to pressure fluctuations when the mixture of gas and air is injected into the combustion chamber and rapid changes in volume during combustion. These vibrations can generate extremely high resonance sounds within the exhaust stack, which occur within an acoustically closed pipe. This depends on the thickness, length, etc. of the exhaust stack, but the length of the exhaust stack varies depending on the conditions at the site where the combustion equipment is installed, so if the length satisfies the conditions, such resonance noise will always occur. There is a risk of

(Means for Solving the Problems) The purpose of the present invention is to provide a combustion device with an exhaust stack that does not have such inconveniences. The combustion cylinder is equipped with a combustion cylinder that surrounds the combustion surface of the burner, and the combustion cylinder communicates with the outside only through an exhaust pipe connected to the burner, and the combustion cylinder and other wall parts are connected to the open end of the root of the exhaust pipe. In those facing each other, a sound absorbing material is provided on the wall surface portions.

(Example) An example of the present invention will be described with reference to an instantaneous water heater shown in the drawings.

In the drawing, 1 is a premixing gas burner equipped with a fan 2 that supplies all of the combustion air as primary air;
3 indicates a combustion shell surrounding the combustion surface 1a of the burner 1; 4 indicates an exhaust pipe connected to the combustion shell 3;
communicates with the outside only through the exhaust pipe 4. Reference numeral 5 indicates a hydrothermal exchanger facing into the combustion shell 3, and the combustion exhaust gas combusted in the gas burner 1 is heat exchanged in the hydrothermal exchanger 5 and then discharged to the outside via the exhaust stack 4. It is not particularly different from conventionally known combustion devices.

The present invention is such that when the wall portion 6 of the combustion cylinder or the like faces the root opening end of the exhaust pipe 4, a sound absorbing material 7 is provided on the wall portion 6,
In the structure shown in FIG. 1, an exhaust pipe connection part 8 is formed by expanding the upper part of the combustion shell 3, and an exhaust pipe 4 is connected to the side of the part 8, and the root of the exhaust pipe 4 of the connection part 8 is connected to the exhaust pipe connection part 8. A sound absorbing material 7 was attached to the wall surface portion 6 facing the opening end. However, this wall portion 6 is not limited to the one formed at the connecting portion 8. As shown in FIG. Needless to say, the bottom surface portion of the exhaust adapter 9 facing the root opening end of the exhaust pipe 4 may be connected to the exhaust pipe 4, for example.

The sound absorbing material 7 is made of rock wool (density 20Kg/m ³ to 70
Kg/m ³ ) or glass wool sound-absorbing felt, which was fixed to the wall portion 6 with a wire mesh or a punching plate 10 or the like.

(Function) When the sound absorbing material 7 is attached to the wall surface of the combustion shell or other wall surface facing the root opening end of the exhaust pipe as described above, the sound waves acting on the wall surface portion can be absorbed by the sound absorbing material 7, and the exhaust pipe has an acoustic This resulted in a state where the pipe was not closed, and the generation of abnormal resonance noise was prevented.

That is, in the combustion apparatus shown in Fig. 2, which is equipped with a bent exhaust pipe 4 of 60 mm in diameter and 5 m3 in length, which will inevitably generate abnormal noise if the inventor does not take measures, the wall portion 6 has a density of 30 Kg/m. ^3. When the rock wool sound absorbing material 7 having a thickness of 25 mm and having excellent heat resistance was provided with the surface covering the wire mesh 10 without an air layer behind it, the resonance sound was no longer generated.

(Effects of the invention) As described above, the present invention can reduce the extremely high sound levels generated inside the exhaust pipe by simply attaching the sound absorbing material to the combustion cylinder and other wall parts facing the root opening end of the exhaust pipe. It has the effect of eliminating scientific resonance.

[Brief explanation of the drawing]

Figure 1 shows one example of implementing the present invention.
The figure is a cut-away side view, FIG. 2 is a cut-away side view showing another embodiment, and FIG. 3 is a cut-away cross-sectional view taken along the - line. 1... Gas burner, 2... Fan, 3... Combustion body, 4... Exhaust pipe, 7... Sound absorbing material.

Claims (1)

[Scope of utility model registration request] A premix burner equipped with a fan that supplies all of the combustion air as primary air, and a combustion shell surrounding the combustion surface of the burner, the combustion shell communicating with the outside only through an exhaust pipe connected to the burner, Further, a combustion device with an exhaust stack, in which a wall surface portion of a combustion cylinder or the like faces the root opening end of the exhaust pipe, and a sound absorbing material is provided on the wall surface portion.