JP2806318B2 - Air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner having a cross flow fan.

[0002]

2. Description of the Related Art A cross-flow fan is a type of fan having a fan rotor having a large number of blades curved in the direction of rotation. Cause. This air flow has a small flow rate, a high flow velocity, and is particularly suitable for an air conditioner that requires a uniform flow in the rotation axis direction.

However, the cross flow fan generates an NZ sound having a frequency corresponding to the product NZ of the number of revolutions N and the number of blades Z, a 2NZ sound having a frequency twice as high as the NZ sound, and the like. FIG. 4A is a graph showing a frequency spectrum of noise generated from the air conditioner having the above-described cross flow fan. As shown in the figure, this frequency spectrum has 688H shown by an arrow A.
The peak of z and the peak of 1.37 kHz indicated by arrow B are apparent. Since the number of blades Z of the fan rotor used in this cross flow fan is 35, and the number of revolutions is about 1195 rpm, the peak indicated by arrow A is due to the NZ sound, and the peak indicated by arrow B. It can be seen that the peak is due to the 2NZ sound. And since the sound having such a remarkable peak in the frequency spectrum can be clearly distinguished from other noises,
Tends to be harsh and uncomfortable.

[0004] In order to reduce the unpleasant noise, a proposal for improving the fan rotor has been made by the present applicant (Japanese Patent Application No. 6-340831). The fan rotor in this proposal is configured by arranging a plurality of blades in a circumferential direction at a random pitch angle to form an impeller, and furthermore, arranging a plurality of the impellers in a rotation axis direction. At this time, there is a phase difference between adjacent impellers,
In addition, at least two or more types of phase differences exist. In a cross-flow fan using such a fan rotor, peaks of NZ sound and 2NZ sound are dispersed, so that harsh noise can be reduced.

[0005]

However, the fan rotor of the cross flow fan proposed above comprises a plurality of impellers in which the blades are arranged at random pitch angles in the circumferential direction. Moreover, it is necessary to provide a structure in which at least two or more types of phase differences exist between adjacent impellers, and the structure is complicated. Therefore, although the harsh noise generated by the NZ sound and the 2NZ sound can be reduced, there is a problem in that the complexity of the structure of the fan rotor causes an increase in cost.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional drawbacks, and has as its object to reduce annoying noise generated from a cross flow fan by a simple configuration. Is to provide.

[0007]

Therefore, the air conditioner according to the first aspect of the present invention provides a cross flow fan comprising a scroll portion 4 which extends from the back of a fan rotor 3 to an air outlet 19 to form a flow passage for conditioned air. In the air conditioner provided with, the swelling portion 5 swelling toward the fan rotor 3 side is formed in the scroll portion 4.

In the air conditioner of the first aspect, the bulging portion 5
As a result, turbulence is generated in the conditioned air circulating, whereby harsh noise can be reduced. Therefore, the silence can be improved with a simple configuration.

The air conditioner according to claim 2 is characterized in that the size of the bulging portion 5 is smaller than the size of the scroll portion 4 in the direction of the rotation shaft 3a of the fan rotor 3.

The air conditioner according to claim 3 is characterized in that the bulging portion 5
Of the scroll portion 4 is about 1/3 to
It is characterized in that the bulging portion 5 is arranged at approximately the center of the scroll portion 4 in the direction of the rotation shaft 3a.

In the air conditioner according to the second or third aspect, the turbulent flow can be reliably generated by providing the bulging portion 5 in a part of the scroll portion 4, so that the noise reduction can be reliably improved. It is possible to do.

The air conditioner according to a fourth aspect of the present invention is characterized in that a recessed portion 6 is formed on the back of the bulging portion 5 and the recessed portion 6 is used as a part storage room for piping or the like.

In the air conditioner of the fourth aspect, the back surface of the bulging portion 5 is used as a component storage room. Therefore, the space can be effectively used and the size can be reduced.

[0014]

Next, specific embodiments of the air conditioner of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a longitudinal sectional view showing an application example when the present invention is applied to an indoor unit of a separation type air conditioner as the above embodiment. As shown in the figure, this indoor unit has a casing 1 provided with a front grille 17 having a front suction port 18 formed therein and an upper grill 15 having an upper suction port 16 formed therein. Has an inverted V-shaped indoor heat exchanger 2. Thus, the indoor heat exchanger 2 is connected to the reverse V
The reason why it is formed in a letter shape is to obtain the maximum heat exchange volume in the determined casing volume, and the indoor heat exchanger 2 is curved so as to be convex on the front side and the rear side. Is
This is to make the indoor unit compact without reducing the heat exchange volume. Further, a fan rotor 3 having a rotating shaft 3a extending in a direction substantially perpendicular to the drawing is provided downstream thereof so as to be sandwiched by the indoor heat exchanger 2. The fan rotor 3, a scroll portion 4 smoothly connected from the back of the fan rotor 3 to the outlet 19, and a tongue portion 13 provided along the rotation axis 3 a of the fan rotor 3 so as to face the same. This constitutes a cross flow fan. In the figure, reference numeral 14 denotes a drain pan for receiving drain water generated in the indoor heat exchanger 2, and the tongue 13 is formed integrally with the drain pan 14. Further, the scroll portion 4 has an intermediate portion between the back portion of the fan rotor 3 and the outlet 19 protruding toward the fan rotor 3, thereby forming a swelling portion 5 bulging toward the fan rotor 3. Is formed with a recessed portion 6. Since the scroll portion 4 is provided with a gentle downward gradient from the back of the fan rotor 3 to the outlet 19, a recess 20 is formed as an empty space in the casing 1 at the back of the scroll portion 4. It has become.

On the other hand, the indoor heat exchanger 2 constitutes a refrigerant circuit by being connected to a compressor, an outdoor heat exchanger and the like provided in an outdoor unit (not shown) so as to be able to circulate the refrigerant. An auxiliary pipe 7 formed by covering a liquid pipe 7a and a gas pipe 7b with a heat insulating material 7c is connected to the heat exchanger 2. The auxiliary pipe 7 is connected to the communication pipe 8 and connected to the outdoor unit. FIG. 3 is a partially transparent perspective view showing the vicinity of the pipe connection portion 10 where such connection is made. Like the auxiliary pipe 7, the connecting pipe 8 is formed by covering the liquid pipe 8a and the gas pipe 8b with a heat insulating material 8c. The connection between the connecting pipe 8 and the auxiliary pipe 7 is made by the liquid pipe 7a of both pipes 7, 8. , 8a,
The gas pipes 7b, 8b are tightly fastened to each other by the flare nuts 11, 11 so that gas leakage does not occur. In the vicinity of this connection portion, both the pipes 7 and 8 are provided with cuts 7d and 8d in the heat insulating materials 7c and 8c for piping work.
At the time of piping work, the cuts 7d and 8d are opened to expose the flare nuts 11 and 11 on the other hand, and after work is closed again to ensure heat insulation. However, since the diameter of the flare nuts 11 and 11 is larger than that of the gas pipes 7b and 8b and the liquid pipes 7a and 8a, the pipes 7 and 8 at the connection part project outward from the other parts. ing. And the connection part which has such a protrusion part is called the piping connection part 10 in this specification. The pipe connection section 10 is disposed in the recess 20 formed in the back of the scroll section 4. In this indoor unit, the recess 6 formed in the scroll section 4 is connected to the pipe connection as shown in FIG. The projecting portion of the pipe connecting portion 10 by the flare nut 11 is held by the recessed portion 6 and the back and bottom surfaces of the casing 1 by using the space as an arrangement space for the portion 10 (see FIG. 2).

FIG. 1 is a partially transparent perspective view of the indoor unit. A pipe connecting portion 10 shown in FIG.
Are shown by broken lines. FIG. 2 shows that the recessed portion 6 is formed on the back surface of the scroll portion 4 and the recessed portion 6 is used as a space for disposing the pipe connection portion 10.
As shown in FIG. And the rotation shaft 3a of the fan rotor 3
The dimension B of the bulging part 5 in the direction is about 1 / 2.5 of the corresponding dimension A of the scroll part 4, and specifically, the dimension A of the scroll part 4 is 630 mm. The dimension B of the part 5 is 250 mm. The bulging part 5 is provided with a scroll part 4 in the direction of the rotation shaft 3a.
Is provided at a substantially central position. Note that 12 in FIG.
Is an electrical component box for storing electrical components and the like.

In the indoor unit of the air conditioner, the cross flow fan functions by rotating the fan rotor 3 to generate a vortex. Then, the room air is sucked into the casing 1 from the upper surface suction port 16 and the front surface suction port 18 according to the vortex airflow, and heat is exchanged by the indoor heat exchanger 2 to be conditioned air. After passing through the fan rotor 3, the conditioned air gradually changes its flow direction to the front side along the scroll portion 4, and is blown out from the outlet 19 into the room again. By the way, the scroll part 4 is provided with a bulging part 5 which bulges toward the fan rotor 3 at a part thereof. Therefore, turbulence is generated by the bulging portion 5 in the conditioned air flowing along the scroll portion 4 by the action of the cross flow fan. In other words, a flow in a direction intersecting with the scroll portion 4 is added by the bulging portion 5 to the two-dimensional flow in a plane along the scroll portion 4, thereby forming a three-dimensional flow. And the turbulence of the conditioned air thus generated reduces the harsh noise that appears as a peak in the frequency spectrum.The result of measuring the noise of this indoor unit is represented by the frequency spectrum. This is shown in FIG. The number of blades Z and the number of revolutions N of the fan rotor 3 are the same as those in the conventional example shown in FIG.
As is clear from the figure, in this indoor unit, noise having peaks at 688 Hz and 1.37 kHz, which has been annoying in the conventional example, is dispersed, and the peak on the frequency spectrum has disappeared. Therefore, in this indoor unit, the generated noise is close to white noise, and NZ sound and 2NZ
It can be seen that harsh noise due to sound and the like is reduced. Such a function can be obtained by forming the bulging portion 5 on the scroll portion 4 with various sizes. Is about one dimension of the scroll part 4
３ to と き, and it has been confirmed that the best result can be obtained when this is arranged at the center of the scroll section 4. In order to reduce the unpleasant noise as described above, only the expanding portion 5 formed on the scroll portion 4 is required.
Therefore, the quietness can be improved by a simple configuration capable of avoiding an increase in cost.

Further, a concave portion 6 is formed on the back surface of the expansion portion 5, and the concave portion 6 is used as a space for arranging the pipe connection portion 10. In particular, since the portion of the pipe connection portion 10 that protrudes to the outer peripheral side is accommodated, the recess 20 can be minimized in size, and the casing 1
The indoor unit can be converted into a compact form by effectively utilizing the internal space. In the above description, the recessed portion 6 is used as a piping space for the piping connection portion 10. However, this can be used as a general component storage room, and depending on the configuration of the indoor unit, other piping and components may be stored. It may be.

Although the specific embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and can be implemented with various modifications within the scope of the present invention. In the above description, the air conditioner is configured as an indoor unit of a separation type air conditioner, but may be configured as an integrated air conditioner having a cross flow fan, for example. The bulging portion 5
Is linear in the direction of the rotation axis of the fan rotor 3. For example, if there is a shape that appropriately generates turbulent air-conditioned air, it may be changed to such a shape. It is also possible to provide irregularities on the surface.

[0021]

According to the air conditioner of the first aspect of the present invention, turbulence is generated in the conditioned air circulated by the bulging portion, thereby reducing harsh noise. Therefore, the silence can be improved with a simple configuration.

In the air conditioner of the second or third aspect, the turbulent flow can be reliably generated by providing the bulging portion in a part of the scroll portion, so that the noise reduction can be reliably improved. Becomes possible.

Further, in the air conditioner of the fourth aspect, the back surface of the bulging portion is used as a component storage room. Therefore, the space can be effectively used and the size can be reduced.

[Brief description of the drawings]

FIG. 1 is a partially transparent perspective view of an indoor unit of an embodiment of an air conditioner of the present invention.

FIG. 2 is a longitudinal sectional view of the indoor unit.

FIG. 3 is a partially transparent perspective view showing a pipe connection part of the embodiment.

FIG. 4 shows a frequency spectrum of noise of the air conditioner,
(A) is for the conventional example, and (b) is for the indoor unit of the air conditioner of this embodiment.

[Explanation of symbols]

 Reference Signs List 3 fan rotor 4 scroll part 5 bulging part 6 concave part 19 outlet

Claims (4)

(57) [Claims] 1. An air conditioner comprising a cross flow fan comprising a scroll portion (4) connected from the back of a fan rotor (3) to an outlet (19) to form a flow path for conditioned air. An air conditioner, wherein a bulging portion (5) bulging toward the fan rotor (3) is formed in the scroll portion (4). 2. A rotating shaft (3) of said fan rotor (3).
The air conditioner according to claim 1, wherein in the a) direction, the size of the bulging portion (5) is smaller than the size of the scroll portion (4). 3. The size of the bulging portion (5) is about １ ／ to １ ／ of the size of the scroll portion (4), and the bulging portion (5) is The air conditioner according to claim 2, wherein the air conditioner is disposed at a substantially central position of the scroll portion (4) in the direction (3a). 4. A recess (6) on the back of the bulge (5).
The air conditioner according to any one of claims 1 to 3, wherein the concave portion (6) is used as a component storage chamber for a pipe or the like.