JPH07113447B2 - Combustion device - Google Patents

Description

TECHNICAL FIELD The present invention relates to noise reduction of a domestic combustor such as a water heater and a heater.

2. Description of the Related Art Conventionally, a combustion apparatus of this type has a structure as shown in FIG. 9 as disclosed in, for example, Japanese Patent Laid-Open No. 61-105054.

That is, an air supply port 1 for inhaling air used for combustion is provided on the front surface of the front case 2, and an instrument body 5 including a burner 3, an exhaust fan 4 and the like is surrounded by a back case 6 and the air supply port 1 is provided. A partition plate 7 for covering the above is provided and an air supply passage 8 is formed between the partition plate 7 and the front case 2. Due to the configuration in which the air supply passage 8 is provided, the outside air is guided to the control circuit 9 located at the lower part of the instrument body 5, and the components in the control circuit 9 are cooled and heat is radiated from the instrument body 5 centering on the burner 3. It acts as a guide plate for suppressing the temperature rise of the front case 2, prevents rain from entering through the air supply port 1 and impinges on the instrument body 5 such as the control circuit 9, and occurs when burning in the burner 3 part. I was trying to block the combustion noise.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in such a configuration, the combustion sound generated in the burner 3 is mainly low-frequency sound of about 100 Hz to 300 Hz, and the combustion performance can be maintained when the wind blows, that is, the wind resistance. In order to ensure the performance, the upper, lower, left and right sides of the partition plate 7 are not in close contact with the front case 2 and are opened, so no sound insulation effect is obtained, and the high-frequency sound from the exhaust fan 4 is output to the outside regardless of the partition plate 7. Since it was released, no effect on noise reduction was obtained.

Therefore, in the present invention, the position of the fan is set to the upstream side of the burner, and between the air supply port provided in the lower part of the front case and the appliance body,
By providing a partition plate that has a step so as to cover the lower side of the front case and both sides and covers the fan and burner of the main body of the equipment, the insulation of the radiated sound centering on the high frequency component from the fan and the upper end of the partition plate The first purpose is to further improve the sound deadening effect by the sound deadening and the propagation attenuation by forming a narrowed portion in the air feeding passage leading to the air intake opening to bypass the There is.

The second purpose is to efficiently absorb sound at the noise generation site. A third object is to further enhance the silencing effect and to muffle the specific frequency.

Means for Solving the Problems And in order to solve the above problems, the combustion apparatus of the present invention,
The first is a fan provided on the upstream side of the burner, a combustion chamber provided on the downstream side of the burner, an exhaust section having an exhaust guide provided on the downstream side of the combustion chamber, and a mechanism for supplying fuel to the burner. Section, a front case and a back case that surround a device body including a combustion chamber of a fan and a burner, an exhaust unit, and a mechanism unit, an air supply port provided at a lower portion of the front case, an air supply port and a device body. Between the bottom and both sides of the front case, and between the fan and the burner located at the bottom of the front case, and with a partition plate with multiple steps, bypass the upper end of the partition plate from the fan. A plurality of throttle portions are formed in the air supply passage leading to the air supply port.

A second aspect of the invention is directed to a fan provided upstream of the burner, a combustion chamber provided downstream of the burner, an exhaust section having an exhaust guide provided downstream of the combustion chamber, and a fuel for the burner. A front case and a back case that enclose an instrument body including a fan, a burner, a combustion chamber, an exhaust section, and a mechanism section, a plurality of air supply ports provided under the front case, A section with a sound-absorbing material placed close to the bottom and both sides of the front case between the air outlet and the main body of the equipment and facing the suction port of the fan that covers the fan and burner located at the bottom of the front case. A partition plate having a V-shaped recess is provided to form an air supply passage that bypasses the upper end of the partition plate from the fan and reaches the air supply port. Furthermore, the third aspect of the present invention provides a muffler on the partition plate.

With the above-described configuration, the combustion device of the present invention has a plurality of stepped portions provided on the partition plate in the path through which noise from the instrument body centering on the fan propagates to the air supply port provided in the front case. In a narrow space surrounded by a case and a partition plate, a plurality of cross-sectional area changes are given, and in terms of an acoustic circuit, a multistage expansion type silencer is configured to reduce noise emitted from the air supply port. is there.

Further, in the combustion apparatus of the second invention, the recess having the sound absorbing material of the partition plate is provided on the surface facing the fan suction port, and the sound from the fan is directly absorbed, so that the noise is attenuated before reaching the air supply port. It is what is done.

Furthermore, in the combustion device of the third aspect of the present invention, since the muffler is arranged in the path through which noise from the instrument body centering on the fan propagates to the air supply port provided in the front case, the sound is silenced from the air supply port. The radiated noise is reduced.

Embodiment Hereinafter, a case where one embodiment of the present invention is applied to a water heater will be described with reference to the accompanying drawings.

1 and 2, a fan is provided upstream of the burner 10.
11 has a combustion chamber 12, a heat exchanger 13 and an exhaust duct on the downstream side.
Exhaust parts 15 having 14 are connected in an airtight manner one after another. The burner 10 is connected to a mechanism portion 17 having a fuel connection port 16 for adjusting the flow rate of fuel according to the load. Further, a water pipe 20 is connected to the water supply connection port 18 from a water mechanical section 19 for adjusting the water pressure and the water amount to the heat exchanger 13. Further, the heat exchanger 13 to the hot water supply connection port 21 are similarly connected by a hot water supply pipe 22. The instrument body 23 is housed in a back case 25 together with an electrical equipment box 24.

On the other hand, the front case 26 has a plurality of air inlets at the bottom.
27 and the front side of the burner 10 and the fan 11, and the front case 26
A partition plate 30 having a plurality of step portions 29 is attached to the lower side and both side edges of the partition plate. As a result, the fan from the air supply port 27
By 11 the throttle portion 31 is formed in the air supply passages 28 and 33 that bypass the upper end of the partition plate 30. A frame 32 for projecting the exhaust duct 14 is provided above the front case 26. Table case
26 is joined to the back case 25 to seal the instrument body 23.

Next, the operation of the configuration of this embodiment will be described. Air necessary for combustion (shown by a solid arrow) flows into the lower part of the front case 26 from the air supply port 27. Most of the inflowing air is guided upward through the air supply passage 28 and diverted at the upper end of the partition plate 30,
It flows into the air supply passage 33. The air is supplied to the burner 10 by the fan 11. In addition, the amount of fuel supplied from the fuel connection port 16 is set by the mechanism unit 17 in an amount corresponding to the load.
Guided to 10. Fuel and air are burned in the combustion chamber 12 by the burner 10 and become high-temperature combustion gas to reach the heat exchanger 13.
The combustion gas, which has been deprived of heat in the heat exchanger 13 and has become low-temperature exhaust gas, is collected in the exhaust unit 15 and discharged from the exhaust duct 14 to the atmosphere. On the other hand, the water that has entered from the water supply connection port 18 to the heat exchanger 13 from the water mechanical part 19 through the water pipe 20 is heated by the combustion gas to become hot water, and passes through the oil supply pipe 22 to reach a predetermined location from the hot water connection port 21. Is supplied to. The fan 11 is controlled by the control circuit in the electrical equipment box 24 according to the load. Further, with respect to wind and rain when installed outdoors, the rain first enters through the air supply port 27, but the partition plate 30 that is in close contact with the periphery of the front case 26 prevents the appliance body 23 from being affected. The wind blows from each direction as well as from the front, but there are multiple air supply ports around the front case 26.
Since 27 is provided, pressure balance can be obtained against wind from any direction, and deterioration of combustion performance can be prevented. On the other hand, the noise from the instrument main body 23 is a mechanical sound centered on a low-frequency component of about 100 Hz to 300 Hz emitted from the exhaust guide 14 and a high-frequency sound of 1 KHz or more emitted from the inlet of the fan 11. The latter sound is diffused in the space surrounded by the front case 26 and the back case 25 (indicated by the dashed arrow), propagates in the path opposite to the air flow, and is radiated from the air supply port 27 to the outside. .

At that time, the direct sound emitted is attenuated by the sound insulation performance of the partition plate 30 and radiated from the air supply port 27, while the sound waves reflected in the case by the partition plate 30 are separated by the partition close to the front case 26. Since the plate 30 is installed so as to cover the fan 11 and the burner 10, it bypasses the upper end of the partition plate 30 to supply air.
28, 33 are propagated, and in particular, the air supply passage 28 has a plurality of step portions 29 provided in the partition plate 30 so that the throttle portion 31 is formed in the air supply passage 28, as shown in FIG. Since a multi-stage expansion type silencer is configured, the noise radiated at the air inlet 27 is significantly reduced due to the sound deadening effect when passing through the feeder passage 28 and the attenuation due to the propagation distance length to the air inlet 27. To be done.

Also, since the partition plate 30 itself becomes large in plan view,
Secondary noise emission caused by the vibration of the partition plate 30 itself due to the vibration due to the rotating part such as 11 and the pressure fluctuation due to the combustion itself is prevented by increasing the rigidity of the step part 29.

Further, in FIG. 4, the sound absorbing material 34 is provided on the step portion 29 of the air supply passage 33 on the side opposite to the throttle portion 31, so that it does not become a resistance to the intake air flow and can be installed in the noise propagation passage, A greater noise reduction effect can be achieved.

In the embodiment shown in FIGS. 5 and 6, a partition plate 36 having a concave portion 35 having a substantially U-shaped cross section is provided on the opposite side of the fan 11 suction port, and the concave portion 35 is provided in the air supply passage 28. The height is determined and a sound absorbing material 37 is provided.

In this embodiment, since the sound absorbing material 37 is installed on the opposite side of the fan 11 suction port where the most noise is radiated, efficient sound absorption can be performed, and the partition 35 can be positioned by the size of the recess 35, The recess 35 also has a reinforcing effect on the partition plate 36.

7 and 8 show an embodiment in which the resonance type silencer 38 is provided in the air supply passage 28, and the height of the resonance type silencer 38 determines the air supply passage 28 and the mounting position. Is provided at a position that does not resist the air flow from the air supply port 27.

As a result, the size of the resonance silencer 38 is set for the frequency component such as the peculiar rotation sound generated from the fan 11, so that the noise reduction effect is obtained. Needless to say, various mufflers are used depending on the noise frequency component.
Further, the partition plate 39 can be positioned by the height of the resonance silencer 38, and the partition plate 39 can be reinforced.

EFFECTS OF THE INVENTION As described above, the present invention provides the air supply port at the lower portion of the front case, and the plurality of the air supply ports are provided in close contact with the periphery of the front case so as to cover the fan and the burner between the instrument body and the air supply port. By arranging the partition plate with steps, it is possible to form a multi-stage tension type sound deadening structure in the air supply passage consisting of the partition plate and the front case, maintaining rain resistance and wind resistance performance and significantly reducing noise. Can be achieved. Further, the reinforcing effect of the partition plate can be obtained by the plurality of step portions, and secondary noise due to vibration of the partition plate itself can be prevented. Further, by providing the sound absorbing material on the step portion, sound can be absorbed without increasing the pressure loss on the air supply passage side, and the noise can be further reduced.

In addition, the partition plate placed in the front case is provided with a recess with a sound absorbing material and a substantially U-shaped cross section at a position facing the fan suction port, so that a direct sound containing a lot of high frequency components radiated from the fan is generated. Can absorb sound effectively. Further, by making the depth dimension of the recesses coincide with the front case depth dimension, positioning can be performed when the partition plate is mounted, passage resistance can be stabilized, and variations in combustion performance can be suppressed. Further, similar to the above-mentioned occurrence, the concave portion also has a reinforcing effect on the partition plate itself.

In addition, the partition plate placed in the front case was provided with a silencer at a position where it did not resist the flow of the supplied air, and the height of the silencer was used to determine the size of the air supply passage. It is possible to achieve effective noise reduction by stabilizing the size of the silencer and by arbitrarily setting the size of the muffler with respect to the frequency components such as the peculiar rotation speed generated from the fan.

[Brief description of drawings]

FIG. 1 is an external perspective view of a gas water heater provided with a device according to an embodiment of the present invention with a front case removed, FIG. 2 is a longitudinal cross-sectional view of relevant parts, and FIG. 4 and 5 are longitudinal cross-sectional views of main parts showing another embodiment, FIG. 5 is an external perspective view showing the other embodiment without a front case, and FIG. 6 is a vertical cross-sectional view of main parts of the same. FIG. 8 is a front view showing another embodiment, FIG. 8 is a longitudinal sectional view of relevant parts, and FIG. 9 is a longitudinal sectional view of essential parts of a conventional gas water heater. 10 …… Burner, 11 …… Fan, 12 …… Combustion chamber, 14 …… Exhaust guide, 15 …… Exhaust section, 17 …… Mechanical section, 23 …… Apparatus body, 25 …… Back case, 26 …… Front side Case, 27 ... Air inlet,
28 …… Air supply passage, 30, 36, 39 …… Partition plate, 31 …… Restrictor, 35 …… Recess, 37 …… Sound absorbing material, 38 …… Resonance silencer.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomonori Aso 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References 62-52743 (JP, U) Actual 52- 121736 (JP, U) Actually open Sho 61-186951 (JP, U) Actually open Sho 53-11633 (JP, U)

Claims (3)

[Claims] 1. A fan provided upstream of a burner, a combustion chamber provided downstream of the burner, an exhaust section having an exhaust guide provided downstream of the combustion chamber, and the burner. A front case and a back case that surround a device main body that includes a mechanism that supplies fuel, the fan, the burner, the combustion chamber, the exhaust section, and the mechanism, and a plurality of supply units provided in the front case. A partition having an air outlet, a plurality of stepped portions that are in close contact with the lower side and both sides of the front case between the air supply port and the appliance body, and that cover the fan and the burner located under the front case. And a plate, and a plurality of steps are formed in an air supply passage that bypasses the upper end of the partition plate from the fan and reaches the air supply port. 2. A fan provided upstream of the burner, a combustion chamber provided downstream of the burner, an exhaust section having an exhaust guide provided downstream of the combustion chamber, and the burner. A front case and a back case that surround a device main body that includes a mechanism that supplies fuel, the fan, the burner, the combustion chamber, the exhaust unit, and the mechanism, and a plurality of feeders provided with the front case. An air outlet is closely attached to the lower side and both sides of the front case between the air supply opening and the appliance body, and is opposed to a suction port of the fan that covers the fan and the burner located under the front case. A partition plate having a recess having a substantially U-shaped cross section with a sound-absorbing material is provided at a position to form an air supply passage that bypasses the upper end of the partition plate from the fan and reaches the air supply port. Combustion device. 3. The combustion device according to claim 1, wherein the partition plate is provided with a silencer.