JP2758070B2 - Cross flow blower - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a cross flow blower provided in an air conditioner or the like.

2. Description of the Related Art As a structure of a conventional cross flow blower, a structure as shown in FIG. 10 has been proposed.

In FIG. 10, an impeller unit 2 composed of a plurality of blades 1 is disposed at the center, and a rear guider 3 and a stabilizer 4 are disposed in close proximity to and opposed to each other to form an air flow path. 5 and an outlet 6 are provided to constitute a cross flow blower.

Further, a volume resonator having an opening 8a in the rear guider 3.
7a and a quarter-wave resonator 7b are provided,
Is provided with a quarter-wave resonator 7b having an opening 8b.

A cross-flow blower having a structure as shown in FIG. 10 is easily thinned as compared with other blowers, and can perform suction and discharge of air on one side, and is widely used in air conditioners.

Further, the provision of the resonator makes it possible to reduce noise at the design frequency.

Problems to be Solved by the Invention However, the crossflow blower having the above configuration has problems such as higher noise and lower efficiency than other blowers such as a centrifugal blower.

In general, the design frequency of a quarter-wave resonator (air column resonator, sand branch) is given by the following equation.

Here, C: sound velocity, L: tube length It is known that the noise reduction effect increases as the number (number) of these quarter-wave resonators increases.

However, in the crossflow blower with a resonator having the above-described configuration, many resonators cannot be efficiently accommodated, so that noise cannot be sufficiently reduced. At the same time, it is difficult to design the resonance frequency at the intended frequency.

In addition, the design frequency and the silencing effect of the volume resonator (Helmholtz resonator) are given by the following equations.

Here, S _b: short pipe section area, l _b: short pipe Director, V: a cavity volume, S: duct area that is, by increasing ensure volume V, silencing effect of the resonator it can be seen that a can be increased.

However, in the crossflow blower with a resonator having the above-described configuration, a large resonator cannot be efficiently accommodated, so that noise reduction cannot be sufficiently achieved. Similarly, it is difficult to design the resonance frequency at the intended frequency.

For volume resonators, the silencing effect is reduced when fluid flows into the resonator in a flow field.

Therefore, in the crossflow blower with a resonator having the above-described configuration, the noise is further reduced due to the influence of the flow.

The present invention solves the above-described problems, and aims to reduce the noise of the cross flow fan, to provide a cross flow blower that efficiently stores the resonator and effectively utilizes the flow field in the volume resonator. It is intended to provide.

Means for Solving the Problems In order to solve the above problems, the cross flow blower of the present invention is provided with a resonator having an opening facing or close to the flow path, and a fluid is passed through the opening. No sound pressure is obstructed by the transmitting thin film.

Operation With the above configuration, the opening of the resonator is blocked by a thin film that does not allow fluid to pass through but transmits sound pressure, preventing the flow of fluid into the resonator, preventing the reduction of the resonance effect, and suppressing noise. In addition to achieving the effect, it is possible to prevent cavity noise and whistling noise generated when the fluid collides with the opening, and to effectively utilize the limited space.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

 1 to 7 show respective basic elements.

In FIG. 1, a cross flow fan formed by combining an impeller unit 12 having a plurality of blades 11 arranged in a columnar shape in a rotation axis direction is disposed at a center, and a rear guider 13 and a stabilizer 14 are arranged close to and opposed to the cross flow fan. It is arranged to form an air flow path, and an inlet 15 and an outlet 16 are provided.

Further, the rear guider 13 is provided with a volume resonator 17a and a quarter-wave resonator 17b having an opening 18a, and the stabilizer 14 is provided with a quarter-wave resonator 17b having an opening 18b.

These quarter-wavelength resonators 17b are configured as curved tube or bent-type wavelength resonators in order to make effective use of the limited space. For the volume resonator 17a, a short tube blade 19 of the resonator is used.
By forming a curved tube or a bending type, the volume portion 20 can be arranged so as to effectively utilize the limited space, and the volume portion 20 is formed in a rectangular shape so as to effectively utilize the limited space. be able to.

Regarding the position of the arrangement of the volume resonator 17a and the quarter-wavelength resonator 17b, it is desired that the position has a high sound pressure distribution.

FIG. 11 shows an iso-noise diagram, where the hatched portion is a place where the sound pressure is high, and it is desirable to arrange it in the vicinity or downstream of this.

In FIG. 2, 11 is a blade, 12 is an impeller alone, 13
Is the rear guide, 14 is the stabilizer, 15 is the suction port, 16
Denotes an outlet, which is the same as FIG.

Reference numeral 21 denotes a heat exchanger, and a rear guide is provided near the suction port 15.
13, the stabilizer 14 is provided. Reference numeral 22 denotes a filter, which is provided between a suction panel 23 provided corresponding to the suction port 15 and the heat exchanger 21.

24 is a dew tray provided at the lower end of the heat exchanger 21,
It is supported by the stabilizer 14.

Reference numeral 25 denotes a front panel provided in connection with the suction panel 23, and a bent quarter-wavelength resonator 27 is provided therein, and the opening 28 has a heat exchanger 21 on the back surface of the front panel 25.
Are provided opposite to each other.

Due to the resonance effect of the quarter-wave resonator 27, the impeller
The noise generated from 2 can be silenced.

In FIG. 3, 11 is a blade, 12 is an impeller alone, 13
Is the rear guider, 14 is the stabilizer, 11 is the suction port, 16
Is an outlet, which is the same as FIG. Reference numeral 31 denotes a bent tube or a bent quarter-wavelength resonator having a heavy structure provided with a large number of openings 32 in the rear guide 13.

It should be noted that a superposed single structure may be used instead of the double structure.

FIGS. 4 (a) and 4 (b) show a front view and a side view of one of the multi-structure quarter-wave resonators 31. FIG.

With this structure, the limited space can be effectively used, and a certain frequency band can be silenced.

In FIG. 5, 11 is a blade, 12 is an impeller alone, 13
Is a rear guider, 14 is a stabilizer, 15 is a suction port, 16
Is an outlet, which is the same as FIG.

Reference numeral 41 denotes openings of the half-wavelength resonator provided in the rear guider 13, which are arranged in several rows along the direction of air flow.

FIG. 6 shows a cross-sectional view of FIG. 5, in which a half-wavelength resonator 42 is provided between two adjacent openings 41 along the flow direction of air. The sound propagation path in the half-wavelength resonator 42 includes a sound propagation path 43a in the flow field and a sound propagation path 43b passing through the half-wavelength resonator 42. Assuming that the length of the propagation path 43a is L and the length of the propagation path 43b is 2L, the frequencies f _ra and f _rb that resonate in the respective propagation paths 43a and 43b are Becomes

Therefore, the primary mode is calculated for the propagation path 43a, and the secondary mode is calculated for the propagation path 43b. Therefore, when n = 1 and n = 2 are substituted into the expressions (1) and (2), Therefore, f _ra = f _rb ... (3), and sounds with the same frequency but different phase differences are actively silenced.

Further, the half-wavelength resonator 42 has the resonance effect of the frequency of the equation (2), and can mute the sound.

The half-wavelength resonator 42 has a shape that protrudes from the rear surface of the rear guider 13 to secure a half-wavelength path difference between the propagation paths 43a and 43b. By inclining the pipelines, the path difference can also be ensured.

That is, FIG. 7 is a plan view of the half-wavelength resonator 44 shown in FIG. 6 as viewed from the direction indicated by the arrow A, and shows the sound propagation path in the half-wavelength resonator 44 in a linear flow field. It is composed of a path 45a and a sound propagation path of the bent half-wavelength resonator 44.

Here, a portion surrounded by a broken line is a half-wavelength resonator 44 provided on the rear surface of the rear guider 13.

Assuming that the length of the propagation path 45a is L and the length of the propagation path 45b is 2L, the frequencies that resonate in the respective propagation paths 45a and 45b
f _ra and f _rb are provided by the equations (1) and (2), and the propagation path 45a
Is calculated for the primary mode and for the propagation path 45b, the result of equation (3) is obtained.

Accordingly, sounds with the same frequency but different phase differences are actively silenced, and the half-wavelength resonator 44 achieves the resonance effect of the frequency of equation (2), thereby achieving silence.

Thus, compared to the half-wavelength resonator 42, the limited space can be effectively used.

FIG. 8 is a sectional view showing a cross flow blower according to an embodiment of the present invention. In FIG. 8, 11 is a blade, 12 is an impeller unit, 13 is a rear guider, 14 is a stabilizer, 15 is a suction port, and 16 is an outlet, which are the same as those in FIG.

Further, the rear guider 13 is provided with a volume resonator 51a having a hole 52a and a quarter-wave resonator 51b, and the stabilizer 14 is provided with a quarter-wave resonator 51b having a hole 52b.

Reference numeral 53 denotes a thin film provided at the openings 52a and 52b so as to transmit a sound pressure but not transmit a fluid, and is made of, for example, vinylidene chloride.

FIG. 9 shows an enlarged sectional view of the volume resonator 51a,
By sticking, it is possible to prevent a fluid from flowing into the resonator 51a and prevent a reduction in the resonance effect. In addition, it is possible to prevent the generation of cavity sound and whistling sound generated when the fluid collides with the opening 52a.

Effect of the Invention As described above, according to the present invention, a resonator having an opening opposed to or close to a flow path is provided, and a thin film that does not allow fluid to pass through but transmits sound pressure is formed in the opening. By
Prevents fluid from flowing into the resonator and prevents the reduction of the resonance effect, thereby achieving a noise reduction effect, not only making effective use of the limited space, but also causing the fluid to collide with the opening. It is possible to prevent the generation of cavity sound and whistling sound.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a basic component of the present invention, FIG. 2 is a cross-sectional view showing another basic component of the present invention, and FIG. 3 is a cross-section showing another basic component of the present invention. FIG. 4 is a front view and a side view showing another basic component of the present invention.
FIG. 6 is a perspective view and a sectional view showing another basic component of the present invention, and FIG. 7 is a view taken in the direction of arrow A in FIG. 6 for explaining another half-wavelength resonator. 8 is a cross-sectional view of a cross-flow blower with a resonator according to an embodiment of the present invention, FIG. 9 is an enlarged cross-sectional view of the resonator of FIG. 8, and FIG. Fig. 11 is an iso-noise diagram of a cross flow blower with a resonator. 11 ... blade, 12 ... impeller unit, 13 ... rear guider, 14 ... stabilizer, 15 ... inlet, 16 ... outlet, 17a ... volume resonator, 17b ... 1/4 wavelength resonator , 18a, 18b… opening, 19… short tube of volume resonator, 2
0: Volume of volume resonator, 25: Front panel, 27: 1
/ 4 wavelength resonator, 28 ... aperture, 31 ... heavy structure 1/4 wavelength resonator, 32 ... aperture, 41 ... aperture, 42,44 ... 1/2 wavelength resonator , 43a, 45a …… The sound propagation path of the flow field, 43b, 45b…
… Half-wave resonator sound propagation path, 51a …… volume resonator,
51b: quarter-wave resonator, 52a, 52b: aperture, 53: thin film

Claims (3)

(57) [Claims] A cross flow fan comprising a plurality of blades arranged in a columnar shape and having a plurality of blades arranged in a columnar shape in a rotation axis direction; a stabilizer arranged adjacent to and opposed to the cross flow fan to form a flow path; Rear guide and
A cross-flow blower provided with a resonator having an opening opposed to or close to the flow path, and closed with a thin film that does not allow fluid to pass through the opening but transmits sound pressure. 2. A cross-flow fan comprising a plurality of blades arranged in a columnar arrangement and having a plurality of blades arranged in a columnar shape, and a stabilizer which is arranged adjacent to and opposed to the cross-flow fan to form a flow path. And a rear guider, and a curved tube or a bent resonator provided with an opening in at least one of the rear guider and the stabilizer, which is closed with a thin film that does not allow fluid to pass through the opening but transmits sound pressure. Cross flow blower. 3. A cross flow fan in which a plurality of blades are arranged in a columnar shape and a plurality of blades are arranged in a columnar shape, and a stabilizer which is arranged close to and opposed to the cross flow fan to form a flow path. And a rear guider, and a curved tube or a bent resonator provided in the front panel near the stabilizer and having an opening on the back surface of the panel, wherein fluid does not pass through the opening but sound The pressure is transmitted by a cross-flow blower closed by a thin film.