JPS5827119Y2 - Combustion blower - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a combustion blower used in a forced air supply/exhaust type hot air heater, etc., and is particularly aimed at suppressing noise within the fan casing.

Conventionally, this type of blower has a centrifugal impeller 2 and an impeller driving electric motor 3 disposed within a fan casing 1, as shown in FIGS. 1 and 2.

In addition, an air supply port 4 is provided in the casing 1 in front of the impeller 2, and a discharge port A and a discharge port B are provided on the circumferential side of the casing 1. and B to the outside of the casing 1.

Further, on the inner periphery of the casing 1 corresponding to the discharge ports A and B, a damper 5 is arranged to slide and rotate along the inner peripheral wall surface.

The opening area of the discharge ports A and B is changed by the rotation of the damper 5, and the ratio of the amount of air discharged from the discharge ports A and B is changed.
is manufactured using a strip-shaped metal plate.

Note that the discharge port A is connected to a combustion section (not shown), and the discharge port B is connected to an exhaust passage (not shown) bypassing the combustion section, and the rotation of the damper 5 causes the discharge ports A and B to The amount of air flowing to the combustion section is adjusted, and the amount of combustion air sent to the combustion section is adjusted.

However, with the above configuration, there were the following drawbacks.

That is, as the centrifugal impeller 2 rotates, not only does the pressure inside the casing 1 become extremely high, but also a large turbulent flow is generated, so that the pressure inside the casing 1 is constantly changing.

As a result, the damper 5 and the like disposed on the inner surface of the casing 1 are excited, and there is a drawback that, for example, a chattering sound is generated between the damper 5 and the inner wall surface of the casing 1.

In addition, the noise caused by the centrifugal impeller 2 or the casing 1
The noise caused by the turbulence of airflow inside the casing has an extremely high level, and this propagates from the discharge ports A and B to other parts, or transmits through the wall surface of the casing 1 and propagates to the outside of the casing 1, resulting in extremely high noise levels. It had the disadvantage of being high.

Note that solid line arrows in FIGS. 1 and 2 indicate air flow.

Therefore, the present invention solves the above-mentioned drawbacks by disposing a sound-absorbing cushioning material between the casing and the damper member.

Hereinafter, one embodiment of the present invention will be described in detail using the accompanying drawings.

As shown in FIG. 3 and FIG. 4, in this embodiment, a centrifugal impeller 7 and an electric motor 8 for driving the impeller are arranged in a fan casing 6, and an air supply port 9 is provided in the casing 6 in front of the centrifugal impeller 7.
In addition, a discharge port C is provided on the circumferential side of the casing 6.
and D are provided.

Then, the air sucked from the air supply port 9 is transferred to the discharge ports C and D.
It is designed to be discharged to the outside of the casing 6 through.

Further, the inner circumference of the casing 6 corresponding to the discharge ports C and D is made of a perforated plate having a large number of small holes 12, and a damper 1 is slidably rotated along the inner circumferential wall surface of the casing 6.
0 are arranged via a cushioning material 11 having, for example, a fibrous sound-absorbing property.

Note that due to the rotation of this damper 10, the discharge ports C and D
The configuration is such that the ratio of the amount of air discharged from the discharge ports C and D is changed by changing the opening area of the discharge ports C and D.

Further, the discharge port C is connected to a combustion section (not shown), and the discharge port bypasses the combustion section and is connected to an exhaust path (not shown). The amount of combustion air sent to the combustion section is adjusted by adjusting the amount of air flowing into the combustion section.

Note that solid line arrows in the figure indicate air flow.

In the case of the above configuration, the rotation of the centrifugal impeller 7 not only creates extremely high pressure inside the casing 6 but also generates large turbulent flow, resulting in a state in which the pressure inside the casing 6 changes significantly. This excites the damper 10 arranged on the inner surface of the casing 6.

However, in this embodiment, since the cushioning material 11 is disposed between the damper 10 and the inner surface of the casing 6, the damper 10 and the inner surface of the casing 6 do not directly collide.

In other words, it is possible to prevent the occurrence of chattering sounds and the like.

Furthermore, the damper 10 of this embodiment is constructed using a perforated plate having a large number of small holes 12, and the cushioning material 11 is made of, for example, a fibrous sound-absorbing material, so that the sound-absorbing effect in this part is improved. can be obtained.

That is, since the noise generated by the centrifugal impeller 7 or the noise generated by the turbulence of air flow inside the casing 6 is absorbed by the buffer material 11, the noise inside the casing 6 can be extremely reduced, and the discharge ports C and Propagates from D to other parts or passes through the wall surface of the casing 6
This makes it possible to significantly reduce noise propagating outside.

As can be seen from the above examples, in the present invention, the flow rate of air discharged from the discharge port can be adjusted by sliding and rotating the damper along the inner wall surface of the casing, and the buffer material between the damper and the casing allows the wind pressure to be adjusted between both. The cushioning material has sound absorbing properties, and the damper has many small holes, so the sound inside the casing is absorbed by the cushioning material through the small holes. , does not come out to the casing 6, and in this respect, no noise is generated.Furthermore, this cushioning material eliminates unnecessary air outflow from the small holes, and the above-mentioned discharge air flow rate can be adjusted accurately.

[Brief explanation of the drawing]

Figure 1 is a side sectional view of a conventional combustion blower, and Figure 2 is a side sectional view of a conventional combustion blower.
3 is a side sectional view of a combustion blower according to an embodiment of the present invention, and FIG. 4 is a sectional view taken along line IV-IV' in FIG. 3. be. 6... Casing, 7... Centrifugal impeller, 9... Air supply port, 10... Damper,
11...Buffer material, 12...Small hole, C1
D...Discharge port.

Claims (1)

[Scope of utility model registration request] The configuration adjusts the flow rate of air discharged from the discharge port by rotating a damper that slides and rotates along the inner wall surface of the casing.A sound absorbing material is disposed between the damper and the casing, and a damper is provided with a sound-absorbing material. A combustion blower with many small holes.