JPS5839A - Water heater using gun type burner - Google Patents

Abstract

PURPOSE:To decrease noise caused by combustion, by providing a normally closed escape port with a lid, in order to escape the pressure in a combustion chamber, by bypassing a throttle part from the side of a combustion chamber toward the outer side, to the side of an air, in an inside diameter throttle part at an exhaust port for combustion gas. CONSTITUTION:An internal pressure escaping passage 8 to escape the pressure in a combustion chamber 6 from a throttled part 7, from the side of a combustion chamber 6 toward the outer side, is provided, and an open port 9 of the passage 8 is closed by a normally closed lid 10. Besides, a passage 11 is branched off from a passage 8, and its open port 13 is normally closed by a lid 14. With such an arrangement, a passage 8 with a lid 10 and a passage 11 with a lid 14 are opened only when a combustion gas is ignited, to bypass a throttled part 7 to escape the pressure abruptly increased in a combustion chamber 6, to decrease noise at an igniting time, and to prevent a combustion characteristic from being deteriorated.

Description

DETAILED DESCRIPTION OF THE INVENTION The object of the present invention is to reduce combustion noise in a hot water boiler using a gun type burner.

For hot water boilers that conventionally use gun-type burners! A muffler was attached to the exhaust section as a means to reduce combustion noise, but this did not have a significant effect considering the cost. Therefore, as another means, burners such as vaporization type and pot 2 were developed in order to reduce noise by changing the combustion method of the burner, but the cost of the burner was high,
Due to problems such as the extremely long preheating time required, which makes it ineffective as an instant hot water heater, and insufficient combustion durability, it has not yet become a mainstream hot water boiler. A gun-type burner is used because some combustion noise is unavoidable.

By the way, it has been generally known that noise can be reduced by narrowing the inner diameter of the combustion gas exhaust port. However, if the inner diameter of the exhaust port is narrowed down too much, there are problems such as a sudden pressure rise in the combustion chamber at the time of ignition, which causes combustion to become unstable, resulting in abnormal combustion or abnormally loud ignition noise.

Furthermore, if you narrow the exhaust port and increase the pressure inside the combustion chamber, the combustion reaction speed will slow down and complete combustion will not occur.
There were also problems such as the tendency to generate soot and Co. Therefore, there was no method of reducing combustion noise by throttling the exhaust port.

Therefore, the present invention solves such problems and realizes noise reduction.

According to experiments, in a hot water boiler using a gun-type burner for general household use with an input of 30,000 to 40,000 Kcal/h, the relationship between the exhaust port inner diameter and combustion noise (represented by the C range) is approximately φ5o, as shown in Figure 6. A slight effect began to be seen at φ4o or less, and a significant effect was obtained when the diameter was reduced to φ4o or less. Note that FIG. 7 shows experimental data of combustion noise spectra for exhaust port inner diameters of φ100 and φ40. The value of 5 sdBc is a level of combustion noise that is almost inaudible to the human ear, and is at the same level as a hot water boiler of the same capacity using an evaporative burner.

In order to eliminate incomplete combustion caused by narrowing the inside diameter of the exhaust port, a throttle ring 2 is provided at the end of the flame stabilizing plate 10 in the combustion head part of the gun type bar shown in FIG. The secondary air coming out of the slit 3 provided at the outer edge of the nozzle 4 may be sent as close as possible to the oil 5 sprayed from the nozzle 4. To this end, the smaller the aperture diameter φD of the aperture ring 2, and the greater the distance H between the tip of the aperture ring 2 and the tip of the flame-holding plate 1, the more incomplete combustion can be eliminated. However, this configuration has a problem in that the pressure within the combustion chamber rapidly increases during ignition, resulting in loud ignition noise.

Therefore, it is necessary to also prevent the sudden pressure rise inside the combustion chamber that occurs due to narrowing the inner diameter of the exhaust port described above.

In order to prevent a sudden pressure rise in the combustion chamber at the time of ignition, as shown in Figure 6, by gradually increasing the pressure of oil sent to the nozzle, the amount of combustion will increase in accordance with the pressure rise, and the pressure in the combustion chamber will decrease. The pressure also rises gradually, and no sudden pressure rise occurs. However, if the pressure is increased too slowly, there will be an excess of air at the time of ignition, resulting in a large amount of coke.

According to experiments, t of 1 to 3 seconds was optimal for a gun type burner with a capacity of 30,000 to 40,000 Kcal/h.

When the internal diameter of the exhaust port is set to φ4o or less, it is not possible to completely prevent a sudden pressure rise in the combustion chamber at the time of ignition only by excluding the above-mentioned oil supply pressure.

Therefore, the present invention has a hot water boiler constructed as shown in FIGS. 2, 3, and 4. That is, the combustion chamber 6
A relief passage 8 is provided from the throttle section 7 to the outside from the combustion chamber side so as to release the internal pressure, and the opening 9 to the outside is provided with a lid 1° so as to be in a normally closed state. If this alone is not sufficient to prevent the rapid pressure rise, a passage 11 branched from the passage 8 is provided and the opening 13 is connected to the constriction part 7.
A lid 14 is provided on the opening 13 so as to face a part 12 on the outside, that is, the atmosphere side, so as to be in a closed state at normal times. That is,
The passage 11 and the lid 14 are characterized in that they are configured to bypass the throttle part 7 and guide combustion gas from the combustion chamber 6 side to the atmosphere side 12 beyond the throttle part 7 only during ignition.

In Fig. 2, 16 is the can body, 16 is a baffle placed inside the can body at the top of the combustion chamber 6, 17 is the exterior, 18 is the top, and 19 is the bottom of the can body facing the combustion chamber. , 20 is a gun type burner with a burner head facing inside the bartero 19.

The blower branch groove of the burner used in the hot water boiler of the foregoing and invention needs to have the ability to cover the increase in ventilation resistance due to narrowing the exhaust lower and send a sufficient amount of air necessary for combustion. However, when the exhaust throttle diameter is set to φ4o with an input of 30,000 to 40,000 Kcal/h, the outer diameter of the blower is φ2
00 turbofan and similar capacity are sufficient.

As described above, according to the present invention, the combustion noise, which has traditionally been a problem in hot water boilers using gun-type burners, can be reduced to the extent that it hardly becomes a problem in practice, and moreover, the ignition noise and combustion characteristics can be reduced. The above-mentioned problems can be minimized and the effects are great.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an example of the head portion of a gun type burner used in a hot water boiler of the present invention, Fig. 2 is a sectional view of a hot water boiler of an embodiment of the present invention, and Fig. 3 is a sectional view of a hot water boiler according to an embodiment of the present invention. Fig. 4 is a sketch of an example of the pressure relief passage during ignition, Fig. 6 is a combustion sound-exhaust port inner diameter characteristic diagram, Fig. 6 is an hourly characteristic of oil supply pressure, and Fig. 7 is an enlarged view of the exhaust part. is a combustion noise spectrum diagram. 6... Combustion chamber, 7... Throttle part) 8...
...Escape passage 9...Opening S10...
... Lid 11 ... Branched passage 112 ...
...Atmospheric side 113...Opening section 14...
・・・Name of agent with lid 0 Patent attorney Toshio Nakao
1 other person Figure 1 Figure 2 Figure f Figure 3 Figure 4

Claims (2)

[Claims] (1) The internal diameter of the combustion gas exhaust port is restricted, and even if there is ventilation resistance due to the restriction of the exhaust port, the blower mechanism has the ability to supply sufficient air necessary for combustion, and the nozzle at the time of startup. An oil feeding mechanism that removes oil feeding pressure, and a relief port having a lid that releases pressure inside the combustion chamber at the time of ignition are arranged in the exhaust throttle section to bypass the exhaust throttle section from the combustion chamber side to the outside to the atmosphere side. A hot water boiler using a gun-type burner. (2) A hot water boiler using a gun-type burner as set forth in claim 1, characterized in that the internal diameter of the exhaust throttle portion is set to φ60 or less.