JP3291909B2 - Duct 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 a duct air conditioner in which an air conditioning unit installed in a space above a ceiling or the like and a terminal unit having an air outlet opened in a living space are connected via a duct. It is.

[0002]

2. Description of the Related Art As shown in FIG. 16, for example, an air-conditioning unit 1 installed in a space above a ceiling and having an air-conditioning blower 5 and a heat exchanger 6 built therein and an outlet 7 opened to a living space R are provided. A duct air conditioner configured by connecting a terminal unit 2 having a terminal unit 2 via a duct 3 is well known in the related art (for example, see Japanese Patent Application Laid-Open No. 62-268828).

[0003]

However, in recent years, there has been a tendency for the space above the ceiling in a building to be narrowed, and there has been a demand for an improvement in workability. Is being sought.

In order to satisfy the above requirements, it is necessary to reduce the thickness of the air conditioning unit 1 and the terminal unit 2 and the diameter of the duct.

When the air-conditioning unit 1 is made thinner, the air-conditioning blower 5 is downsized, but a high-speed operation is inevitable in order to obtain a sufficient air volume, and the operation noise is increased. In particular, when a heat exchanger 6 of a total heat exchange type is used, a higher speed operation is inevitable to cover an increase in ventilation resistance, and operation noise is further increased.

Further, even when the diameter of the duct 3 is reduced, the pressure loss in the duct 3 increases, so that high-speed operation of the air-conditioning blower 5 is required, and the operating noise increases.

Further, when the terminal unit 2 is made thinner, the pressure loss increases and the airflow distribution of the air blown into the room deteriorates. That is, the air flow W ₁ blown out from the air outlet 7 which is positioned to face the downstream end of the duct 3, an air flow W ₂ blown out from the air outlet 7 immediately below the downstream end of the duct 3 The wind speed will differ greatly (see FIG. 17).

[0008] Due to the above phenomenon, the operation sound generated on the air conditioning unit 1 side is radiated into the room from the air outlet 7 of the terminal unit 2 as a radiated sound, so that the acoustic environment of the indoor living space R deteriorates.

In the apparatus disclosed in Japanese Patent Application Laid-Open No. Sho 62-268928, a centripetal fan is built in the terminal unit. It is not enough to reduce the radiation of the operation sound propagating from the unit side into the room.

[0010] The present invention has been made in view of the above points, and improves the airflow distribution of the airflow blown out from a terminal unit, and also radiates the operation sound propagating from the air conditioning unit side into the room. It is an object of the present invention to be able to reduce the total.

[0011]

The basic structure of the present invention is as follows.
In a duct air conditioner in which an air conditioning unit having a built-in air conditioning blower and a heat exchanger and a terminal unit having an outlet opened to a living space are connected via a duct,
In the terminal unit, a low static pressure type terminal blower,
A swirl guide which is located on the suction side of the terminal blower and guides the conditioned air blown out of the duct to the outer peripheral side of the terminal blower.

In the present invention, there are the following preferred embodiments.

[0013] Between the terminal blower and the spiral guide, a number of radial guide pieces are provided at predetermined intervals in the circumferential direction for guiding the conditioned air guided and guided by the spiral guide to the suction side of the terminal blower. Is preferred.

It is more preferable that the blades of the radial guide and the impeller of the terminal blower have a sound absorbing structure.

[0015]

The duct air conditioner of the present invention has the following effects.

That is, the conditioned air obtained by the air conditioning unit is sent to the terminal unit via a duct, and in the terminal unit, after being guided to the outer peripheral side of the terminal blower by the spiral guide, the terminal blower is started. The air is blown into the indoor living space from the air outlet. At this time, the air flow distribution of the blown air flow to the indoor living space is made uniform by the guide operation of the spiral guide and the low static pressure blowing operation by the terminal blower, and the air guide is guided from the duct outlet by the guide operation of the spiral guide. The longer air circulation path to the outlet and the sound insulation and sound absorption by the terminal blower act synergistically to generate large operating noise inside the air conditioning unit and propagate to the terminal unit through the duct. Radiation to the living space will be greatly reduced. Since the pressure loss in the terminal unit can be reduced by the flow control effect of the terminal blower itself, the operating speed of the air-conditioning blower on the air-conditioning unit side can be reduced (that is, the operating sound can be reduced).

Also, between the terminal blower and the spiral guide, a number of radial guides for guiding the conditioned air guided and guided by the spiral guide to the suction side of the terminal blower are arranged at predetermined intervals in the circumferential direction. In this case, the radial guide exerts a rectifying effect of adjusting the flow state of the airflow sucked into the terminal blower, and also exerts a sound insulating effect of insulating the operation sound propagating through the duct.

Further, when the blades of the radial guide and the impeller of the terminal blower have a sound absorbing structure, the radial guide and the impeller function as a splitter type silencer.

[0019]

According to the present invention, the conditioned air obtained by the air conditioning unit and sent to the terminal unit through the duct is guided inside the terminal unit by the spiral guide to the outer peripheral side of the terminal blower. Later, the air is blown into the indoor living space from the outlet through the terminal blower, so that the airflow of the blown air flow to the indoor living space is generated by the guiding operation of the spiral guide and the low static pressure blowing operation by the terminal blower. There is an excellent effect that the distribution is made uniform and the indoor air conditioning efficiency can be improved. In addition, the air circulation path from the duct outlet to the air outlet is lengthened by the guide operation of the spiral guide, and the sound insulation and sound absorption by the terminal blower work synergistically to generate in the air conditioning unit. Radiation of loud driving noise that propagates to the terminal unit through the indoor living space is greatly reduced, and the air conditioning unit and the terminal unit are made thinner,
Even when the diameter of the duct is reduced, there is an excellent effect that the noise in the indoor living space can be reduced to a level that can be practically used. In addition, since the pressure loss in the terminal unit can be reduced by the flow control effect of the terminal blower itself, the operation speed of the air-conditioning blower on the air-conditioning unit side can be reduced, which also contributes to power saving.

In addition, between the terminal blower and the spiral guide, a number of radial guides for guiding the conditioned air guided by the spiral guide to the suction side of the terminal blower are arranged at predetermined intervals in the circumferential direction. In this case, the radial guide will not only act as a rectifier to regulate the flow condition of the airflow sucked into the terminal blower, but will also act as a sound insulator to block the operating noise that propagates through the duct, and will be used to reduce the indoor living space. The effect that the radiated sound can be further reduced is obtained.

Furthermore, when the radial guide and the impeller of the terminal blower of the terminal blower have a sound absorbing structure, the radial guide and the impeller function as a splitter-type silencer, thereby reducing the radiated sound in the indoor living space. The effect of greatly contributing is obtained.

[0022]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

First Embodiment FIGS. 1 and 2 show a main part (that is, a terminal unit) of a duct air conditioner according to a first embodiment of the present invention.

The overall configuration of the duct air conditioner of this embodiment is as follows.
An air conditioning unit 1 which has the same structure as that described in the section of the prior art (see FIG. 16), is installed in the space above the ceiling, and incorporates an air conditioning blower 5 and a heat exchanger 6;
A terminal unit 2 having an outlet 7 opened to the living space R is connected via a duct 3. In the case of the present embodiment, a centrifugal multi-blade fan is employed as the air-conditioning blower 5, and a total heat exchanger is employed as the heat exchanger 6. Reference numeral 8 denotes a fresh outside air intake to the air conditioning unit 1.

The terminal unit 2 has a box-shaped casing 9 to which the duct 3 is connected.
Is installed with its lower end facing the opening 10 formed in the ceiling C. At the lower end of the casing 9, a decorative panel A having outlets 7, 7,... Capable of blowing in four directions is provided so as to cover the opening 10.

A centripetal fan 11 as a low static pressure type terminal blower is attached to the top plate 9a of the casing 9 in a downward direction. The centripetal fan 11 has a conditioned air W
It is not intended for pumping, so it is to be operated at an extremely low speed. The conditioned air W is to be pumped by the air-conditioning blower 5.

The centripetal fan 11 is a two-dimensional centrifugal impeller having a large number of two-dimensional blades 12, 12,... Laid between a main plate 13 and a side plate 14 facing the main plate 13. 15 and a fan motor 16 for driving the impeller 15 to rotate. Each of the blades 12
As shown in FIG. 3, a metal cell 19 formed with a large number of small holes 18, 18,... And a sound absorbing material 20 filled in the cell 19 have a sound absorbing structure. The material of the cell 19 is preferably an iron plate, an aluminum plate or the like, and the sound absorbing material 20 is preferably glass wool, rock wool or the like.

The duct 3 is provided with the centripetal fan 1.
The casing 9 is connected to one end of the casing 9 at an eccentric position so that the conditioned air W can be blown out so as to oppose the rotating direction of the casing 1.

Further, in the casing 9, a spiral guide 17 for guiding the conditioned air W blown out from the duct 3 to the outer peripheral side of the centripetal fan 11, which is located on the suction side of the centripetal fan 11, is disposed. Has been established. The spiral guide 17 is made of a sound absorbing material such as foam synthetic resin, and includes a spiral guide surface 17 a surrounding the outer periphery of the centripetal fan 11, and a conical guide surface 17 b surrounding the discharge side of the centripetal fan 11. It has. Reference numeral 21 denotes an outlet passage that connects the discharge side of the centripetal fan 11 and the outlets 7, 7,.

The duct air conditioner configured as described above operates as follows.

The conditioned air W obtained by the air conditioning unit 1 is
After being sent to the terminal unit 2 through the duct 3 and guided inside the terminal unit 2 to the outer peripheral side of the centripetal fan 11 by the spiral guide 17, the outlets 7, 7. It is blown out to the indoor living space R more.

At this time, the air guide W of the spiral guide guide 17 and the low static pressure blowing action of the centripetal fan 11 make the airflow distribution of the blown air flow W to the indoor living space R uniform, and at the same time, the spiral guide guide 17 is provided. The air guiding path from the outlet of the duct 3 to the outlet 7 is lengthened by the guiding and guiding action of the duct 3, and the sound insulation / sound absorbing action of the centripetal fan 11 acts synergistically to be generated in the air conditioning unit 1 and the duct 3
The radiation of the loud driving sound to the indoor living space R transmitted to the terminal unit 2 via the terminal unit 2 is greatly reduced. Therefore, the air conditioning unit 1 and the terminal unit 2 are made thinner,
Even when the diameter of the duct 3 is reduced, the noise in the indoor living space R can be reduced to a level that can be put to practical use.
Moreover, in the case of the present embodiment, since the spiral guide 17 is made of a sound absorbing material, the sound absorbing effect of the spiral guide 17 can be obtained. In addition, since the pressure loss in the terminal unit 1 can be reduced by the flow control effect of the centripetal fan 11 itself, the operation speed of the air-conditioning blower 5 of the air-conditioning unit 1 can be reduced (that is, the operation sound can be reduced). I can do it.

Further, the impeller 15 of the centripetal fan 11
In the above, the blades 12, 12,... Have a sound absorbing structure, so that the impeller 15 exhibits a function as a splitter type noise reduction device, and the sound absorbing effect is further improved.

Incidentally, the operating noise and static pressure of the single fan of the centrifugal multi-blade fan used as the air-conditioning blower 5 and the two-dimensional centripetal fan used as the terminal blower 11 were measured. The results shown were obtained. 4 and 5, the case of the centrifugal multi-blade fan is indicated by a dotted line, and the case of a centripetal fan is indicated by a solid line.

According to the above results, for example, the reference wind speed
(Ie, 800 m ³ / Hr), the centripetal fan has much lower operating noise than the centrifugal multi-blade fan, so that the operating noise of the centripetal fan in the terminal unit 2 has almost no effect on the operating noise. Although the static pressure obtained is very small as compared with the centrifugal multi-blade fan, it is a positive pressure. Therefore, even if the centripetal fan is operated in the terminal unit 2, it does not become a resistance but rather acts as a pressurizing fan. From these facts, it can be understood that the provision of the centripetal fan 11 in the terminal unit 2 is suitable for reducing the driving noise.

Second Embodiment FIGS. 6 and 7 show a main part (that is, a terminal unit) of a duct air conditioner according to a second embodiment of the present invention.

In the case of the present embodiment, in the terminal unit 2 of the first embodiment, the conditioned air W guided and guided by the spiral guide 17 is provided between the centrifugal fan 11 and the spiral guide 17 in the terminal unit 2 of the first embodiment. A number of wing-shaped radial guides 22, 22,... For guiding to the suction side are arranged at predetermined intervals in the circumferential direction.

Each of the radial guides 22 has a sound absorbing structure made of a sound absorbing material (for example, foamed synthetic resin, foamed metal, etc.) as shown in FIG. 8, or a plurality of small holes 23 as shown in FIG. , 23... Formed of a metal (for example, an iron plate or an aluminum plate), and a sound absorbing material (for example, glass wool, rock wool, etc.) 2 filled in the cell 24.
5 is preferable. The other configuration is the same as that of the first embodiment, and the description is omitted to avoid duplication.

With the above-described configuration, the radial guides 22, 22,... Exhibit a rectifying function for adjusting the flow state of the conditioned air W sucked into the centripetal fan 11, and the operating noise propagated through the duct 3. It also exhibits the sound insulation effect of insulating the sound. Moreover, the radial guide 2
When the sound absorbing structure is used for the radial guides 22, 22,.
.. Also function as a splitter type silencer. Therefore, the airflow distribution improving effect and the radiation sound reducing effect in the indoor living space R are further improved. Other functions and effects are the same as those of the first embodiment, and thus the description is omitted to avoid duplication.

Third Embodiment FIGS. 10 and 11 show a main part (that is, a terminal unit) of a duct air conditioner according to a third embodiment of the present invention.

In this embodiment, a three-dimensional centripetal fan is used as the terminal blower 11 in the terminal unit 2 of the second embodiment. The impeller 1 of this centripetal fan 11
5 is provided with a large number of blades 27, 27... Provided radially on the outer periphery of a boss 26 having a substantially hyperbolic cross section connected to the fan motor 16. Since this type of centripetal fan 11 is also of a low static pressure type, it is needless to say that the same effect as described in the first and second embodiments can be expected even if it is disposed in the terminal unit 2.

Fourth Embodiment FIGS. 12 and 13 show a main part (that is, a terminal unit) of a duct air conditioner according to a fourth embodiment of the present invention.

In this embodiment, a propeller fan is used as the terminal blower 11 in the terminal unit 2 of the second embodiment. The impeller 15 of the propeller fan 11 is
Four propeller type blades 29 are radially provided on the outer periphery of a cylindrical boss 28 connected to the fan motor 16. Since the propeller fan 11 is also of a low static pressure type, it is needless to say that the same effect as described in the first and second embodiments can be expected even if the propeller fan 11 is disposed in the terminal unit 2.

Fifth Embodiment FIGS. 14 and 15 show a main part (that is, a terminal unit) of a duct air conditioner according to a fifth embodiment of the present invention.

In the case of the present embodiment, a mixed flow fan is employed as the terminal blower 11 in the terminal unit 2 of the second embodiment. The impeller 15 of the mixed flow fan 11 has a frusto-conical boss 30 connected to the fan motor 16 on the outer periphery thereof.
The blades 31 are provided radially. Since the mixed flow fan 11 is also of a low static pressure type, it is needless to say that the same effect as that described in the first and second embodiments can be expected even if it is disposed in the terminal unit 2.

The invention of the present application is not limited to the configuration of each of the above embodiments, and it is a matter of course that the design can be changed as appropriate without departing from the gist of the invention.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a main part (that is, a terminal unit part) of a duct air conditioner according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a cross-sectional view illustrating a blade structure of a terminal blower in the duct air conditioner according to the first embodiment of the present invention.

FIG. 4 is an air volume-operation sound characteristic diagram comparing operation sounds between a centripetal fan used as a terminal blower and a centrifugal multi-blade fan used as an air conditioning blower in Embodiment 1 of the present invention.

FIG. 5 is an air volume-static pressure characteristic diagram comparing static pressures of a centripetal fan used as a terminal blower and a centrifugal multi-blade fan used as an air-conditioning blower in Embodiment 1 of the present invention.

FIG. 6 is a longitudinal sectional view of a main part (that is, a terminal unit portion) of the duct air conditioner according to the second embodiment of the present invention.

FIG. 7 is a sectional view taken along line VII-VII of FIG. 6;

FIG. 8 is a sectional view showing an example of a radial guide in the duct air conditioner according to the first embodiment of the present invention.

FIG. 9 is a sectional view showing another example of the radial guide in the duct air conditioner according to the first embodiment of the present invention.

FIG. 10 is a longitudinal sectional view of a main part (that is, a terminal unit part) of a duct air conditioner according to a third embodiment of the present invention.

11 is a sectional view taken along the line XI-XI in FIG.

FIG. 12 is a longitudinal sectional view of a main part (that is, a terminal unit part) of a duct air conditioner according to a fourth embodiment of the present invention.

FIG. 13 is a sectional view taken along line XIII-XIII of FIG.

FIG. 14 is a longitudinal sectional view of a main part (that is, a terminal unit part) of a duct air conditioner according to a fifth embodiment of the present invention.

FIG. 15 is a sectional view taken along line XV-XV in FIG. 14;

FIG. 16 is a side view showing the overall configuration of a conventionally known duct air conditioner.

FIG. 17 is a longitudinal sectional view of a main part (that is, a terminal unit part) in a conventionally known duct air conditioner.

[Explanation of symbols]

1 is an air conditioning unit, 2 is a terminal unit, 3 is a duct,
Is an air conditioning blower for suction, 5 is an air conditioning blower for blowing, 6 is a heat exchanger, 7 is an outlet, 11 is a terminal blower (centripening fan, propeller fan, mixed flow fan), 12 is a blade, 15 is an impeller, 17 Is a spiral guide, 22 is a radial guide, 2
7, 29, 31 are feathers, C is ceiling, R is indoor living space, W
Is harmony air.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI F24F 13/08 F24F 13/08 A (56) References JP-A-5-196243 (JP, A) JP-A-62-268928 ( JP, A) JP-A-57-2939 (JP, A) JP-A-5-203193 (JP, A) JP-A-54-57345 (JP, A) JP-A-6-2875 (JP, A) Hei 6-108993 (JP, A) Japanese Unexamined Patent Publication (Kokai) No. 2-171520 (JP, A) Japanese Utility Model Laid-open No. 2-52044 (JP, U) Japanese Utility Model Application No. 57-174799 (JP, U) Japanese Utility Model Application No. 5-54947 (JP) (U, U) 62-116 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F24F 1/00 F24F 3/044 F24F 13/06 F24F 13/08

Claims (4)

(57) [Claims] 1. A duct air conditioner in which an air conditioning unit having a built-in air conditioning blower and a heat exchanger is connected via a duct to a terminal unit having an air outlet opened in a living space, wherein the terminal unit is provided. Inside, a low static pressure type terminal blower, and a spiral guide that is located on the suction side of the terminal blower and guides the conditioned air blown out of the duct to the outer peripheral side of the terminal blower are provided. A duct air conditioner. 2. A plurality of radial guides for guiding conditioned air guided by the spiral guide to the suction side of the terminal blower are arranged at predetermined intervals in the circumferential direction between the terminal blower and the spiral guide. The said claim 1 characterized by the above-mentioned.
A duct air conditioner as described. 3. The duct air conditioner according to claim 2, wherein said radial guide has a sound absorbing structure. 4. The terminal of claim 1, wherein the impeller of the terminal blower has a sound absorbing structure.
The duct air-conditioning ventilator according to any one of claims 1 to 7.