JPH0481594A - Crossflow fan - Google Patents

Abstract

PURPOSE:To utilize a limited space so efficiently as well as to make a noise reduction promotable in an effective manner by installing each of opening ports and resonators in a stabilizer and a rear guider installed as approximatively opposed to a crossflow fan. CONSTITUTION:A crossflow fan is made up of combining an impeller simple 12, columnarly arranged with plural pieces of blades 11, in a turning shaft direction. A stabilizer 14 and a rear guider 13 are installed as approximatively opposed to the crossflow fan, forming a flow passage. Here, a volume resonator 17a or 1/4 wavelength resonator 17b with opening ports 18a, 18b is installed in at least one side of the stabilizer 14 and the rear guider 13. With this constitution, a limited space is effectively utilized and thereby a noise reduction is well promotable in an effective manner.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a cross-flow blower installed in an air conditioner or the like.

2. Description of the Related Art A conventional cross-flow blower structure as shown in FIG. 10 has been previously proposed. FIG. 10 is a sectional view of a conventional cross-flow blower with a resonator. In FIG. 10, a single impeller 2 consisting of a plurality of blades 1 is arranged in the center,
A rear guider 3 and a stabilizer 4 are arranged close to and facing each other to form an air flow path.
and an air outlet 6 are provided to constitute a cross-flow blower.

Further, the rear guider 3 is provided with a volume resonator 7a and a 174-wavelength resonator 7b having an aperture 8a, and the stabilizer 4 is provided with a 174-wavelength resonator 7b having an aperture 8b.

A cross-flow blower having a structure as shown in FIG. 10 is easily made thinner than other blowers, and air can be taken in and discharged from one side, and is widely used in air conditioners. Further, by providing a resonator, it is possible to reduce the noise of the design frequency.

Problems to be Solved by the Invention However, the cross-flow blower configured as described above has problems such as higher noise and lower efficiency than other blowers such as centrifugal blowers.

Generally, the design frequency of a 174-wavelength resonator (air column resonator, site branch) is given by the following formula.

Here, C: speed of sound, L tube length It is known that the silencing effect increases as the number of quarter-wave resonators increases. but,
The cross-flow blower with resonators configured as described above cannot efficiently accommodate many resonators, and therefore cannot achieve sufficient noise reduction. At the same time, it is difficult to design a resonant frequency to match the intended frequency.

Further, the design frequency and silencing effect of the volume resonator (Helmholtz resonator) are given by the following formula.

Here, Sb: Short pipe area, lb・Short pipe length, ■:
Volume of cavity, S: It can be seen that the silencing effect of the resonator can be increased by ensuring a large duct area, that is, volume (2). However, in the cross-flow blower with a resonator configured as described above, it is not possible to efficiently accommodate a large resonator, and therefore it is not possible to achieve sufficient noise reduction. Similarly, it is difficult to design a resonant frequency to match the intended frequency.

Also, for a volume resonator, if fluid flows into the resonator in a flow field, the silencing effect will be reduced. Therefore, the resonator-equipped cross-flow blower configured as described above is further affected by the flow and cannot achieve sufficient noise reduction.

The present invention solves the above problems, and in order to reduce the noise of the cross-flow blower, a cross-flow blower is provided that efficiently stores the resonator and makes effective use of the volume resonator in the flow field. The purpose is to provide

Means for Solving the Problems In order to solve the above problems, the cross-flow blower of the present invention has the following features:
At least one of the rear guider and the stabilizer facing the flow path is provided with a bent pipe or a bent resonator having an opening.

Further, a bent pipe or a bent type resonator having an opening on the back side of the panel is provided in the front panel near the stabilizer.

Further, a bent tube or folded resonator having a superposed single structure or a multilayer structure is provided.

Furthermore, a 172-wavelength resonator is provided, which has two apertures and has a path twice as long as the straight path between the apertures through which normal sound is transmitted.

In addition, a thin film is provided in the aperture of the resonator so that fluid cannot pass therethrough but sound pressure can be transmitted.

Effect With the above configuration, the opening of the bent pipe or bent resonator is provided in the portion of at least one of the rear guider and the stabilizer facing the flow path, and the sound generated in the vicinity is muffled at the tuned resonance frequency. , the limited space can be effectively utilized by the resonator having the above configuration.

In addition, a curved pipe or bent type resonator is installed in the front panel, and its opening is provided on the back of the panel, and the tuned resonant frequency of the sound generated in the vicinity is silenced, so the front panel can be used effectively. It is possible to make effective use of limited space.

Furthermore, in order to utilize space effectively, the efficiency of the resonator can be further increased and noise can be suppressed by forming the curved pipe or folded resonator into a single structure or a stacked structure.

In addition, the curved tube or bending type resonator is configured with a 1/2 wavelength resonator that has two apertures and forms a path twice as long as the straight path between the apertures through which normal sound is transmitted. However, by creating a phase difference of half a wavelength, sounds of the same frequency can be actively silenced, and the resonance effect as a 1/2 wavelength tube can further reduce the noise.

In addition, by providing a thin film that can transmit the sound pressure that causes the fluid to pass through the apertures of the resonator, it prevents the fluid from flowing into the resonator, prevents the reduction of the resonance effect, and achieves a muffling effect. be able to. Furthermore, it is possible to prevent the occurrence of cavity noise or whistling noise caused by fluid colliding with the opening.

Example Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a sectional view showing a cross-flow blower according to a first embodiment of the present invention. In FIG. 1, a cross flow fan consisting of a single impeller 12 in which a plurality of blades J1 are arranged in a cylindrical shape is arranged in the rotation axis direction, and a cross flow fan is arranged in the center, and a rear guider 13 and a stabilizer 14 are arranged close to and facing this. An air flow path is formed, and an inlet 15 and an outlet 16 are provided. In addition, rear guider 1
Volume resonator 17a having aperture 18a at 3 and 1/
A 4-wavelength resonator 17b is provided, and the stabilizer 14 is a 1/4-wavelength resonator having an aperture 18b! 7b is provided.

These 1/4 wavelength resonators 17b are configured as curved tubes or folded wavelength resonators in order to effectively utilize the limited space.
By making 9 into a curved pipe or bending type, the volume part 2
0 can be arranged so as to make effective use of the limited space, and furthermore, the volume portion 2o can be configured in a rectangular shape so as to make effective use of the limited space.

These volume resonators 17a and 174 wavelength resonators 17b
Regarding the placement position, a location with a high sound pressure distribution is desired. FIG. 11 shows a noise equalization diagram, where the shaded area is a location where the sound pressure is high, and it is desirable to arrange it near this area or downstream from this area.

FIG. 2 is a sectional view showing a cross-flow blower according to a second embodiment of the present invention. In Fig. 2, 11 is a blade, 12 is a single impeller, 13 is a rear guide, 14 is a stabilizer,
15 is a suction port, and 16 is a blowout port, which are the same as those shown in FIG. 21 is a heat exchanger, and the suction port 1
It is provided across the rear guide 13 and the stabilizer 14 on the 5 side. 22 is the filter, and the suction port 1
It is provided between the suction panel 23 and the heat exchanger 21 provided corresponding to the heat exchanger 21. 24 is a dew pan provided at the lower end of the heat exchanger 21, and is supported by the stabilizer 14. Reference numeral 25 denotes a front panel connected to the suction panel 23, in which a folded 174-wavelength resonator 27 is provided, and its opening 28 faces the heat exchanger 21 on the back side of the front panel 25. It is provided.

Due to the resonance effect of the quarter wavelength resonator 27, the noise generated from the impeller 12 can be muffled.

FIG. 3 is a sectional view showing a cross-flow blower according to a third embodiment of the present invention. In FIG. 3, 11 is a blade, 12 is a single impeller, 13 is a rear guider, 14 is a stabilizer,
11 is a suction port, and 16 is a blowout port, which are the same as those shown in FIG. Reference numeral 31 denotes a multi-structure bent tube or folded quarter-wavelength resonator provided with a large number of openings 32 in the rear guide 13. Note that a single superimposed structure may be used instead of a multilayer structure.

Figures 4(a) and 4(b) show this layered 1/4 wavelength resonator 31.
1 shows a front view and a side view of one. With this structure, the limited space can be used effectively and a certain frequency band can be muted.

FIG. 5 is a perspective view showing a cross-flow blower according to a fourth embodiment of the present invention. In FIG. 5, 11 is a blade, 12 is a single impeller, 13 is a rear guider, 14 is a stabilizer,
15 is a suction port, and 16 is a blowout port, which are the same as those shown in FIG. 41 is 1 provided on the rear guider 13.
/2 wavelength resonator openings, arranged in several rows along the air flow direction.

FIG. 6 shows a cross-sectional view of FIG. 5, in which the 1/2 wavelength resonator 42
is provided between two adjacent apertures 41 along the air flow direction. The sound propagation path in the 172 wavelength resonator 42 is the sound propagation path 43a in the flow field.
and a sound propagation path 43b passing through the 172-wavelength resonator 42. The length of the propagation path 43a is L1 propagation path 43
If the length b is 2L, each propagation path 43a,
43b, the frequency f1. .

f7. Hato becomes. Therefore, the first mode is calculated for the propagation path 43a, and the second mode is calculated for the propagation path 43b.

Therefore, n=1 and n for equations (1) and (2), respectively.
By substituting =2, we get, therefore f ra=f tb ・
...(3), and the sounds with the same frequency but different phase differences are actively silenced. Further, the 1/2 wavelength resonator 42 can obtain the frequency resonance effect of equation (2), and can muffle sound.

Furthermore, by forming the 1/2 wavelength resonator 42 in a shape that protrudes from the back surface of the rear guider 13, the propagation path 43 a
, 43 whether a path difference of half a wavelength of b is secured, 17
Two-wavelength resonator 44 By slanting the pipe constituting the resonator, a path difference can be ensured.

That is, FIG. 7 shows A of the 172 wavelength resonator 44 in FIG.
The diagram shows a plan view as viewed from the arrow, and the sound propagation path in the 1/2 wavelength resonator 44 is composed of a sound propagation path 45a in a straight flow field and a bent sound propagation path in the 172-wavelength resonator 44. do. Here, the part surrounded by the broken line is the I/2 wavelength resonator 44 provided on the back surface of the rear guider 13. When the length of the propagation path 45a is L1 and the length of the propagation path 45b is 2L, the frequencies f, , , f, which resonate in each of the propagation paths 45a and 45b are determined by equations (1) and (2). ,
For the propagation path 45a, the first mode is
When calculating the second-order mode for b, the result of equation (3) is obtained. Therefore, sounds with the same frequency but different phase differences can be actively silenced, and furthermore, the I/2 wavelength resonator 44 can obtain the frequency resonance effect of equation (2), thereby achieving noise suppression.

In this way, compared to the 172-wavelength resonator 42, the limited space can be used more effectively.

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

Further, the rear guider 13 is provided with a volume resonator 51a having an aperture 52a and a 174 wavelength resonator 51b,
The stabilizer 14 is provided with a 174 wavelength resonator 51b having an aperture 52b. 53 are apertures 52a and 52 so that fluid cannot pass therethrough but sound pressure can be transmitted.
This is a thin film provided in b, and is made of, for example, vinylidene chloride.

FIG. 9 shows an enlarged sectional view of the volume resonator 51a, in which the thin film 2
By pasting 0, it is possible to prevent fluid from flowing into the resonator 51a and prevent the resonance effect from decreasing. Further, it is also possible to prevent the occurrence of cavity sounds and whistling sounds that are generated when fluid collides with the aperture 52a.

Effects of the Invention As described above, according to the present invention, the resonator located in the rear guider, stabilizer, or front panel can muffle the sound generated in the vicinity or the sound that is propagating (with a tuned resonant frequency). However, by configuring the resonator as a curved pipe or bending type, the limited space can be used effectively and the sound can be effectively silenced.

Furthermore, in order to effectively utilize the space, the effect of the resonator can be further increased by making the curved pipe or bending type resonator into a single structure or a multilayered structure.
It is possible to muffle the sound.

In addition, two apertures are provided in a curved tube or bent type resonator, and the resonator is configured into a 1/2 wavelength resonator having a path twice as long as the direct path between the apertures through which normal sound is transmitted. By creating a phase difference of half a wavelength, sounds of the same frequency can be actively silenced, and furthermore, the resonance effect as a 172-wavelength tube can further silence the sounds.

In addition, by providing a thin film that transmits sound pressure without passing fluid through the opening of the resonator, it is possible to prevent fluid from flowing into the resonator, prevent a decrease in the resonance effect, and achieve a muffling effect. It is possible to prevent the occurrence of cavity sounds and whistling sounds caused by fluid colliding with the apertures.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a cross-flow blower with a resonator according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view of a cross-flow blower with a resonator according to a second embodiment of the present invention, and FIG. A sectional view of a cross-flow blower with a resonator in a third embodiment of the present invention, FIG. 4 is a front view and a side view of the resonator in the third embodiment,
5 and 6 are a perspective view and a sectional view of a cross-flow blower with a resonator according to a fourth embodiment of the present invention, and FIG. 7 is a fifth diagram for explaining another 1/2 wavelength resonator. A in
8 is a cross-sectional view of a cross-flow blower with a resonator according to a fifth embodiment of the present invention, FIG. 9 is an enlarged sectional view of the resonator of FIG. 8, and FIG. 10 is a conventional one. A cross-sectional view of the cross-flow blower with a resonator, and FIG. 11 is an iso-noise diagram of the cross-flow blower with a resonator. 11...blade, 12...impeller alone, 13...
Rear guider, 14... Stabilizer, 15... Suction port, 16... Air outlet, 17a... Volume resonator, +7b... 174 wavelength resonator, 18a, 18b
...Aperture opening, 19...Short tube part of volume resonator, 20.
... Volume part of the volume resonator, 25 ... Front panel, 27
...174 wavelength resonator, 28... aperture, 31...
・Heavy structure 174 wavelength resonator, 32...Aperture opening, 41・
...Aperture opening, 42°44...1/2 wavelength resonator, 43
a, 45a... Sound propagation path in flow field, 43b,
45b...1/2 wavelength resonator sound propagation path, 51a
...Volume resonator, 51b...174 wavelength resonator, 5
2a, 52b...opening opening, 53...thin film. Agent Yoshihiro Morimoto Figure 1/7d Figure S Figure 7 Figure M

Claims (1)

[Claims] 1. A cross-low fan formed by combining a single impeller in which a plurality of blades are arranged in a cylindrical shape in the direction of a rotating shaft, a stabilizer disposed adjacent to and facing the fan to form a flow path, and A cross-flow blower comprising a rear guider and a bent pipe or bending type resonator provided with an opening in at least one of the rear guider and the stabilizer. 2. A cross flow fan formed by combining single impellers each having a plurality of blades arranged in a cylindrical shape in the direction of the rotation axis, a stabilizer and a rear guider arranged in close proximity to and facing each other to form a flow path, and a vicinity of the stabilizer. A cross-flow blower equipped with a curved pipe or a folded resonator installed in the front panel of the machine and having an opening on the back side of the panel. 3. The cross-flow blower according to claim 1 or 2, wherein the curved pipes or folded resonators are constructed in a superimposed single structure or a multilayer structure. 4. The bent pipe or the bent resonator is a 1/2 wavelength resonator having two apertures and having a path twice as long as the distance between the apertures. Cross flow blower. 5. A cross flow fan formed by combining a single impeller in which a plurality of blades are arranged in a cylindrical shape in the direction of the rotation axis, a stabilizer and a rear guider arranged adjacent to and facing each other to form a flow path, and the rear guider and the rear guider. A cross-flow blower comprising: a resonator provided with an aperture on at least one side of a stabilizer; and a thin film provided to prevent fluid from passing through the aperture but allow sound pressure to be transmitted.