JP2805763B2 - Gas water heater - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to reducing noise of a driver of a gas water heater.

2. Description of the Related Art Conventionally, as shown in FIGS. 7 and 8, a gas water heater has a blower 1 for supplying combustion air, a gas control device 9 for supplying flammable gas, and a mixture of flammable gas and air for combustion. The combustion chamber 3 was provided with a burner section 2 for performing heat, a heat exchanger 4 for transferring heat during combustion to water, and an exhaust port 6 for discharging burned exhaust gas to the outside of the apparatus through an exhaust passage 7. here
14 is a water pipe, and 13 is a gas pipe.

Problems to be Solved by the Invention In such a configuration, the noise of the gas water heater generally shows a frequency characteristic as shown in FIG. 9, and reducing a large peak near 200 Hz is a major problem for low noise. Met. It has been found that this peak is caused by acoustic resonance determined by the shapes of the combustion chamber, the burner, and the exhaust passage. In other words, the combustion chamber and the burner were formed into an acoustic space as shown in FIG. 10 by the partition plate of the exhaust passage, and had a shape in which volume resonance was very likely to occur. Therefore, the noise generated by the combustion is greatly amplified at the resonance frequency, resulting in large device noise.
And this kind of resonance sound of the gas water heater is determined by the shape as shown by the following equation, and has a relatively low frequency (about 20
0 Hz) in many cases, and it was very difficult to reduce the noise with a sound absorbing material or a sound absorbing muffler. Actually, there is a blower in the bottom plate of the burner, and the formula becomes complicated by considering the opening of the blower suction port. However, it can be basically described by the following formula.

f: resonance frequency, C: sound velocity, S: cross-sectional area of exhaust port, V: volume of combustion chamber, 1: path length of exhaust passage The present invention solves such a conventional problem, and a part of the burner part. By forming a low-pitched sound resistance material, that is, a thin film plate or a perforated plate having a very small aperture ratio, the passage is configured with the same ventilation resistance as the conventional ventilation passage,
Acoustically, the object is to greatly control the resonance characteristics by reducing the acoustic resistance of the wall surface of the space and greatly changing the acoustic system and configuration. As a result, the generation of resonance can be greatly reduced, and the equipment noise of the gas water heater can be significantly reduced.

Means for Solving the Problems The present invention for solving the above problems includes a blower for supplying combustion air, a gas control device for controlling supply of combustible gas, and a burner for mixing and combusting the combustible gas and air. And a combustion chamber with a heat exchanger that transfers heat during combustion to water, an exhaust passage and an exhaust port for discharging burned exhaust gas to the outside of the device, and a part of an outer box of the burner unit, and The portion between the blower and the gas control device was formed of a low acoustic resistance material.

According to the present invention, a part of the burner portion can be made of a low acoustic resistance material by the above-described structure, and a passage is formed with a similar exhaust resistance to a ventilation passage, and the burner is acoustically made of a low acoustic resistance material. Significantly reduce the acoustic resistance of the outer box, greatly change the shape of the acoustic system, suppress resonance characteristics and shift the resonance frequency, and provide a low acoustic resistance material in the low temperature part upstream of the combustion part The purpose is to improve the durability of low acoustic resistance materials. As a result, the generation of resonance can be greatly reduced, and the equipment noise of the gas water heater can be significantly reduced.

Embodiment An embodiment of a gas water heater according to the present invention will be described below with reference to FIGS.

As shown in FIGS. 1 and 2, the gas water heater according to the present invention includes a blower 1 for supplying combustion air, a gas control device 9 for supplying flammable gas, and a flammable gas mixed with air for combustion. A combustion chamber 3 having a heat exchanger 4 for transferring heat at the time of combustion to water; an exhaust passage 7 and an exhaust port 6 for discharging burned exhaust gas to the outside of the apparatus; The plate constituting the bottom plate 12 of the outer case 5 located between the blower 1 and the gas control device 9 is formed of a resin thin film plate 8 as a low acoustic resistance plate. 14 is a water pipe, and 13 is a gas pipe.

In such a configuration, the air supplied from the blower is supplied to the combustion chamber 3 through the ventilation passage surrounded by the burner outer box 5, mixed with the combustible gas supplied from the gas control device 9, and burned. Used for combustion indoors. Here, combustion noise generated by combustion is radiated from the exhaust passage 7 through the heat exchanger 4 on the downstream side, and is radiated from the blower inlet through the ventilation passage of the burner unit 2 on the upstream side. is there. The latter noise is also radiated from the resin thin film plate 8 which is a low acoustic resistance material provided on the bottom plate of the burner unit outer box 5. As a result, when viewed from the acoustic system, the total area of the openings S and S 'becomes very large, and the frequency of acoustic resonance is changed from a low frequency containing much combustion noise to a significantly high frequency. In addition to being able to move to an area, the hermeticity of the acoustic space is acoustically reduced, so that resonance characteristics can be suppressed and moderated. As a result, the generation of resonance noise can be greatly reduced, and the noise of the gas water heater can be greatly reduced. Then, a part of the outer box of the burner, that is, the bottom plate 12 at the position where the gas and the air are mixed between the blower 1 and the gas control device 9 on the upstream side of the combustion, is constituted by a low acoustic resistance plate. Therefore, the durability of the low acoustic resistance plate can be maintained for a long time because it is not exposed to high temperatures, in addition to the effect of noise reduction.

Next, another embodiment of the present invention will be described with reference to FIGS. FIG. 4 differs from the above embodiment in that the low acoustic resistance material is constituted by a perforated plate 10 having a large number of small holes continuously penetrating between the front and back surfaces of the plate. In addition, the perforated plate is formed by sandwiching the metal fibers 16 with a plurality of meshes 17 and rolling (shown in FIG. 6), and the perforated plate is sandwiched between the burner bottom plate 12 and the blower mounting plate 11. And Here, 15 is a motor.

In such a configuration, the air supplied from the blower is supplied to the combustion chamber through a ventilation passage surrounded by a burner outer box, mixed with combustible gas supplied from a gas control device, and combusted in the combustion chamber. used. The small holes of the perforated plate provided on the bottom plate are very small, and the opening area is very small with respect to the plate area. Therefore, the blowing resistance is very high, and the amount of air leaking from the perforated plate is very small, so that the conventional performance can be maintained as the blowing passage. On the other hand, combustion noise generated by combustion is radiated from an exhaust passage through a heat exchanger on the downstream side, and is radiated from a blower inlet through a burner section ventilation passage on an upstream side. The latter noise is also radiated from the perforated plate of low acoustic resistance material provided on the bottom plate of the outer box of the burner. As a result, the total area of the openings becomes very large as in the conventional example, and the frequency of acoustic resonance can be shifted from a low frequency, which contains a lot of combustion noise, to a significantly high frequency range. Since the hermeticity is reduced, the resonance characteristics can be suppressed and the resonance characteristics can be reduced. As a result, the generation of resonance can be significantly reduced. Further, a perforated plate rolled with a metal fiber net has a very high vibration damping effect due to the bending rigidity of the metal fiber. Since the blower is attached to the burner section bottom plate with the perforated plate interposed therebetween, vibration of the blower can be suppressed. Therefore, the vibration noise generated by the vibration of the blower can be greatly reduced, and the vibration of the blower including the motor is reduced by suppressing the vibration, so that the durability life of the blower can be extended. As described above, the apparatus noise of the gas water heater can be significantly reduced by reducing the resonance sound and the vibration noise.

Effect of the Invention As described above, according to the gas water heater of the present invention, since the noise generated by combustion is radiated from a part of the burner part outer box from the exhaust port, the combustion chamber, the exhaust passage, and the burner part The acoustic characteristics of the shape constituted by the above can be changed, the acoustic resonance can be suppressed, and the vibration noise can be reduced by suppressing the vibration of the blower by the perforated plate of the metal fiber. And since the low acoustic resistance plate is installed in the low temperature burner part which mixes air and gas on the upstream side of combustion, the durability of the low acoustic resistance plate can be maintained for a long time because it is not exposed to high temperature. . Therefore, the noise of the gas water heater can be significantly reduced. Further, since the vibration of the blower is reduced, the durable life of the blower can be greatly extended.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a gas water heater according to one embodiment of the present invention,
FIG. 2 is a side sectional view of the gas water heater, FIG. 3 is a sectional view showing an acoustic space of the gas water heater, FIG. 4 is a front sectional view of a gas water heater showing another embodiment of the present invention, 5 is a side sectional view of a main part of the gas water heater, FIG. 6 is a front view of a perforated plate used for the gas water heater, FIG. 7 is a front sectional view of a conventional gas water heater, and FIG. FIG. 9 is a side sectional view of the water heater, FIG. 9 is a noise frequency characteristic diagram of the gas water heater, and FIG. 10 is a cross-sectional view showing an acoustic space of the gas water heater. 1 ... blower, 2 ... burner, 3 ... combustion chamber, 4 ...
Heat exchanger, 5 ... Outer box, 6 ... Exhaust port, 7 ... Exhaust passage, 8 ... Thin plate, 9 ... Gas control device, 10 ... Perforated plate, 11 ... Blower mounting plate, 12 ... … Burner bottom plate, 16 ……
Metal fiber, 17….

Claims (1)

(57) [Claims] 1. A blower for supplying combustion air, a gas control device for controlling supply of combustible gas, a burner unit for mixing the combustible gas with air and burning, and a heat exchange for transferring heat during combustion to water. A burner and a combustion chamber, an exhaust passage and an exhaust port for discharging the burned exhaust gas to the outside of the device, and a part of the outer box of the burner portion and a portion between the blower and the gas control device, which is low. Gas water heater made of acoustic resistance material.