JPH11304176A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a remarkable attenuation of the noise by sufficiently elongating the length of a sound attenuation duct without spoiling the compact construction of the whole. SOLUTION: A supply air duct 4 is formed in a casing 1 such that a return air opening 2 and an air supply opening 3 formed in a casing 1 are communicated with each other. An air supply fan 11 is installed in the supply air duct 4 and it is made of a single suction centrifugal fan. This single suction centrifugal air supply fan 11 is directly connected to a motor 12 and is disposed at the lower portion in the inside of the casing 1. A sound attenuating duct 13 which extends from an air outlet portion of the air supply fan 11 to the air supply opening 3 is formed in a hopper shape and an air volume damper 14 which also works as a sound attenuating splitter is installed at an enlarged portion of the hopper-like sound attenuating duct 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner, and more particularly to an air conditioner suitable for air conditioning a quiet indoor space such as an office building as well as a music hall or a hospital.
The present invention relates to a compact air conditioner capable of reducing noise generated from a fan and the like.

[0002]

2. Description of the Related Art FIGS. 10 and 11 are a front view and a plan view showing the structure of an air conditioner generally used conventionally. In this air conditioner, a return air port 2 and an air supply port 3 are provided on the top surface on both sides in the longitudinal direction of the casing 1, and an air supply air passage 4 communicating the ports 2 and 3 is formed in the casing 1. In addition, an air filter 5, a heat exchanger 6 including a heating coil 6A and a cooling coil 6B, a humidifier 7, and an air supply fan 8 are sequentially arranged in the air supply ventilation passage 4. As the air supply fan 8, a double suction centrifugal fan is used. The motor 9 disposed in the casing 1 below the air supply fan 8 is not shown in the drawing. It was configured by interlocking connection via a belt.

[0003]

However, in the conventional air conditioner having the above-described structure, the air supply fan 8 and the drive motor 9 for the air supply fan 8 are arranged at the upper and lower positions in the casing 1. Under the condition that the vertical dimension of the casing 1 is restricted in order to reduce the size of the entire air conditioner, the noise reduction duct 10 formed from the discharge port of the air supply fan 8 to the air supply port 3 is restricted. The vertical length cannot be secured to a sufficient length. Therefore, noise such as wind noise generated by the operation of the air supply fan 8 cannot be sufficiently reduced.

In order to reduce the size of the air conditioner as a whole while using both suction centrifugal air supply fans 8, it is inevitable to employ air supply fans 8 having a small impeller diameter. If the fan 8 having a small diameter of the impeller is used, the air supply efficiency is reduced, so that the rotation speed of the impeller must be set to a high value. As a result, even if the length of the sound deadening duct 10 can be somewhat increased, There was a problem that noise increased.

The present invention has been made to solve the above-mentioned problems, and provides an air conditioner that can realize a remarkable reduction in noise by sufficiently increasing the length of a silencing duct without impairing the overall compactness. It is intended to be.

[0006]

In order to achieve the above object, an air conditioner according to a first aspect of the present invention is provided with a return air inlet and an air inlet on both sides in a longitudinal direction of a casing.
Forming an air supply passage connecting the return air inlet and the air supply opening in the casing, and arranging an air filter, a heat exchanger, a humidifier, and an air supply fan in order in the air supply air passage, In an air conditioner configured to cause return air flowing into an air supply passage from an air port to flow out of the air supply port through an air filter, a heat exchanger, a humidifier, and an air supply fan, the air supply fan may have one side. This single-intake centrifugal fan is directly connected to a motor and arranged at a lower portion in the casing, and a muffler duct from a discharge port of the air supply fan to the air supply port is formed as a hopper. It is characterized by being formed in.

According to the first aspect of the present invention,
Compared to a double suction centrifugal fan, a single suction centrifugal fan that has the same performance as the double suction centrifugal fan but has a large impeller diameter and high air supply performance, and can be set at a low rotation speed. By using, the noise generated from the air supply fan itself can be reduced without lowering the predetermined air supply performance. Also, by directly connecting this single-suction centrifugal fan to the motor, the muffle duct from the discharge port of the air supply fan to the air supply port can be lengthened vertically without increasing the vertical dimension of the casing. Can be formed.

In addition, by forming the long sound deadening duct in the shape of a hopper, the speed of the airflow flowing through the enlarged portion can be reduced, and the synergistic combination of these measures makes it possible to reduce the noise of the air conditioner as a whole. A significant reduction can be realized.

The air conditioner according to a second aspect of the present invention, in addition to the configuration according to the first aspect of the present invention, further comprises an air volume adjusting damper in a state in which the enlarged portion of the hopper-shaped silencing duct also serves as a silencing splitter. In this case, the noise can be further reduced by the presence of the silencing splitter, and there is no need to provide a separate air volume adjustment damper, simplifying the configuration and simplifying the configuration while supplying air to the air-conditioned room. Can also be adjusted arbitrarily.

The air conditioner according to a third aspect of the present invention is the air conditioner according to the first or second aspect of the present invention, wherein the air filter and the heat exchanger are used for returning air in the air supply passage. In this case, the air flow passage area for the air filter and the heat exchanger can be secured large, and the dimension in the air flow direction (thickness of the air filter, heat Therefore, the ventilation resistance can be remarkably reduced by reducing the number of rows of the coils for the exchanger, so that the energy consumption of the air supply fan can be suppressed and the noise can be further reduced.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 are a front view, a side view, and a plan view of an air conditioner according to a first embodiment of the present invention.

In the first embodiment, the air supply fan 1
1, a single-suction centrifugal fan is used, and the single-suction centrifugal air supply fan 11 is directly connected to a motor 12 and is arranged at a lower portion of the casing 11; A point in which the sound deadening duct 13 from the portion 11a to the air supply port 3 provided on the top surface of the casing 1 is formed in a hopper shape, and an air volume adjusting damper 14 also serving as a sound deadening splitter is disposed in an enlarged portion of the hopper shaped sound deadening duct 13. This is different from the conventional example shown in FIGS. 10 and 11 in that the other components are the same as those of the conventional example shown in FIGS. 10 and 11. Description is omitted.

As shown in FIG. 4, a sound absorbing material 15 in which glass wool and glass cloth are bonded is stretched over the entire inner surface of the sound deadening duct 13. As shown in FIG. A punching metal 16 is provided. In addition, the air volume adjusting damper 14 also serving as the silencing splitter is made of glass wool over the entire outer peripheral surface of a substantially elliptical damper body 18 capable of adjusting a passing air volume (air supply amount) by rotating around a damper shaft 17. A sound absorbing material 19 to which glass cloth is attached is stretched, and the outer periphery thereof is covered with a punching metal 20.

In the air conditioner having the above-described structure, the air supply fan 11 is driven via the motor 12 so that the air returns from the return air system communicating with the room to be air-conditioned to the air supply passage 4 through the return air opening 2. Return air RA flows into the tank. The return air RA flowing into the air supply passage 4 is supplied to the air filter 5, the heat exchanger 6,
The air passes through the humidifier 7 and the air supply fan 11, passes through the sound deadening duct 13, and flows out of the air supply port 3 into the air supply system in the air conditioning target room as air supply SA into the air conditioning target room.

Here, as the air supply fan 11, a single suction centrifugal fan having a larger impeller diameter, higher air supply performance than the double suction centrifugal fan, and capable of setting a lower rotation speed is used. Therefore, it is possible to suppress the generation of noise by the fan 11. Further, by directly connecting such a low-noise air supply fan 11 to the motor 12, it is possible to increase the vertical dimension of the casing 1 without increasing it.
The vertical length of the sound deadening duct 13 can be ensured to be long. When an airflow passes through the long sound deadening duct 13, the inner surface thereof and the damper body 18
A sound absorbing effect is obtained by the sound absorbing members 15 and 19 stretched on the outer peripheral surface of the air duct, and the air supply SA flows out of the air inlet 3 by reducing the flow velocity of the air flow in the enlarged portion of the sound deadening duct 13. This can significantly reduce the noise when the operation is performed.

As a second embodiment of the present invention, as shown in FIGS. 5 and 6, a fan shaft 11a of a single suction centrifugal air supply fan 11 is connected to a flow of return airflow in the air supply passage 4. In the configuration in which the fan shaft 11a of the air supply fan 11 is parallel to the flow direction of the return airflow in the air supply ventilation passage 4, FIG. As shown, the configuration may be such that the positions of the air supply fan 11 and the motor 12 directly connected to the air supply fan 11 are interchanged.

Further, as a third embodiment of the present invention, as shown in FIGS. 8 and 9, an air filter 5 and a heat exchanger 6 disposed in an air supply passage 4 are provided. 4
It is good also as a structure arrange | positioned with respect to the flow direction of the return airflow in the inside. In this case, a large air flow passage area for the air filter 5 and the heat exchanger 6 can be ensured, and the dimension in the air flow direction (the thickness of the air filter,
By reducing the number of rows of coils for the heat exchanger), the ventilation resistance can be remarkably reduced. As a result, the energy consumption of the air supply fan 11 and the noise can be further reduced.

In any of the air conditioners according to the other embodiments of the present invention shown in FIGS. 5, 6, and 7, and FIGS. 8 and 9, the configuration of the sound deadening duct 13 is clearly shown in FIG. Since they are the same as those described above, a detailed description thereof will be omitted.

[0019]

As described above, according to the first aspect of the present invention, as the air supply fan, the same performance as the double suction centrifugal fan is achieved, and the impeller diameter is larger than that of the double suction centrifugal fan. By using a single-suction centrifugal fan that can be set to a low rotation speed because the air supply performance is high by increasing the air supply performance, the noise generated from the air supply fan itself without lowering the specified air supply performance Can be lower. Moreover, by directly connecting the single-suction centrifugal fan to the motor, the muffle duct from the discharge port of the air supply fan to the air supply port can be lengthened vertically without increasing the vertical dimension of the casing. By forming the long sound deadening duct in a hopper shape, the velocity of the airflow flowing through the enlarged portion can be reduced. Therefore, the synergistic effect of these effects provides an effect that remarkable reduction of noise can be realized while reducing the size of the entire air conditioner.

According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, the noise can be further reduced by the presence of the noise reduction splitter, and a separate air volume adjusting damper is required. Therefore, it is possible to arbitrarily adjust the amount of air supplied to the room to be air-conditioned while simplifying the configuration.

Further, according to the third aspect of the invention, in addition to the effects of the first or second aspect, a large air flow passage area for the air filter and the heat exchanger is secured.
By reducing the thickness of the air filter, the number of rows of coils for the heat exchanger, and the like, the ventilation resistance can be remarkably reduced, so that the energy consumption of the air supply fan and the noise can be further reduced.

[Brief description of the drawings]

FIG. 1 is a front view of an air conditioner according to a first embodiment of the present invention.

FIG. 2 is a side view of the air conditioner according to the first embodiment.

FIG. 3 is a plan view of the air conditioner according to the first embodiment.

FIG. 4 is an enlarged vertical sectional side view of a main part of the air conditioner according to the first embodiment.

FIG. 5 is a front view of an air conditioner according to a second embodiment of the present invention.

FIG. 6 is a side view of the air conditioner according to the second embodiment.

FIG. 7 is a front view showing a modification of the air conditioner according to the second embodiment.

FIG. 8 is a front view of an air conditioner according to a third embodiment of the present invention.

FIG. 9 is a plan view of the air conditioner according to the third embodiment.

FIG. 10 is a front view of a conventional air conditioner.

FIG. 11 is a plan view of the conventional air conditioner.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 casing 2 return air inlet 3 air supply inlet 4 air supply ventilation passage 5 air filter 6 heat exchanger 7 humidifier 11 one-sided suction centrifugal air supply fan 12 motor 13 silence duct 14 silence splitter air volume adjusting damper RA return air SA supply Mind

Continued on the front page (72) Inventor Masaaki Shinohara 28, Kubota Air Quality Industrial Park, Utsunomiya City, Tochigi Prefecture Inside the Tochigi Plant (72) Inventor Keiji Watanabe 28 Hirade Industrial Park, Utsunomiya City, Tochigi Prefecture 28 Kubota Air Quality Industrial Corporation Tochigi In-plant (72) Inventor Toshihisa Shimizu 28, Hirade Industrial Park, Utsunomiya, Tochigi Pref.

Claims (3)

[Claims] 1. A casing according to claim 1, wherein a return air inlet and an air supply port are provided on both sides in a longitudinal direction of the casing, and an air supply air passage communicating between the air return opening and the air supply port is formed in the casing. An air filter, a heat exchanger, a humidifier, and an air supply fan are sequentially arranged in the path, and the return air that has flowed into the air supply passage from the air return opening is supplied to the air filter, the heat exchanger, the humidifier, and the air supply fan. In the air conditioner configured to flow out of the air supply port through the air supply port, the air supply fan is a single suction centrifugal fan, and the single suction centrifugal air supply fan is directly connected to a motor to lower the inside of the casing. An air conditioner, wherein a silencing duct from a discharge port of the air supply fan to the air supply port is formed in a hopper shape. 2. The air conditioner according to claim 1, wherein an air volume adjusting damper that also functions as a noise reduction splitter is provided in an enlarged portion of the hopper-like noise reduction duct. 3. The air conditioner according to claim 1, wherein the air filter and the heat exchanger are disposed in an inclined posture with respect to a flow direction of the return air in the supply air passage. .