CN113203119A

CN113203119A - Ceiling embedded air conditioner

Info

Publication number: CN113203119A
Application number: CN202110007920.6A
Authority: CN
Inventors: 明连千寻; 柴田贵范; 清水健
Original assignee: Mitsubishi Heavy Industries Ltd
Current assignee: Mitsubishi Heavy Industries Ltd
Priority date: 2020-01-31
Filing date: 2021-01-05
Publication date: 2021-08-03
Also published as: US20210239329A1; JP2021124017A

Abstract

The invention provides a ceiling embedded air conditioner with simpler structure and further improved performance. The ceiling-embedded air conditioner is provided with: a housing; a motor having an output shaft that is rotationally driven around an axis and that protrudes downward; a main plate fixed to the output shaft and extending radially outward; a turbofan having an impeller; and a heat exchanger through which air sent from the turbo fan passes, the main plate having: a conical section; and a recessed portion defined by a cylindrical plate portion that is formed so as to be recessed inward from the conical portion and extends along the axis, and a disc plate portion that is expanded radially outward from an upper end of the cylindrical plate portion, the cylindrical plate portion being formed with an opening portion that penetrates in the radial direction and through which a circulating flow that comes out of the impeller and goes around above the main plate passes.

Description

Ceiling embedded air conditioner

Technical Field

The present disclosure relates to a ceiling embedded type air conditioner.

Background

As an example of the air conditioning apparatus, a ceiling embedded type air conditioner is widely used. The ceiling-embedded air conditioner mainly comprises: a housing embedded in an indoor ceiling; a motor and a turbofan having an output shaft rotating about an axis extending in an up-down direction; a main plate for fixing the turbofan to an output shaft; and a heat exchanger surrounding the turbofan. When the turbo fan is rotated, the air in the room is taken in from the center portion of the casing, passes through the heat exchanger, and is supplied as cold air or warm air into the room.

As a specific example of such a ceiling-mounted air conditioner, a ceiling-mounted air conditioner described in patent document 1 below is known. In this device, the main plate has a conical shape whose diameter increases radially outward from below toward above. Most of the air taken into the casing flows upward along the outer surface of the main plate, and is sent to the heat exchanger on the radially outer side by the turbo fan. On the other hand, a part of the air taken into the casing bypasses the turbofan from above to form a circulating flow flowing into the upper side of the main plate. In the device described in patent document 1, the circulating flow is used as cooling air for the motor. The air having cooled the motor passes through the opening formed in the main plate, and joins the main flow (that is, the air flow along the outer surface of the main plate) again.

Here, when the angle at which the main flow and the circulating flow merge approaches a right angle, a mixing loss occurs between the two. As a result, performance as an air conditioner may be affected. Therefore, in the device of patent document 1, a bulge portion for guiding the flow direction of the circulating flow is added to the opening portion of the main plate as a new component.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2000-227231

Disclosure of Invention

Problems to be solved by the invention

However, assembling other components to the main board as described above leads to a complicated configuration, and increases the number of components and the number of manufacturing steps. As a result, the manufacturing cost may be increased.

The present disclosure has been made to solve the above problems, and an object of the present disclosure is to provide a ceiling-embedded air conditioner having a simpler configuration and further improved performance.

Technical scheme

In order to solve the above problem, a ceiling-embedded air conditioner of the present disclosure includes: a casing having a suction port formed at the lower center thereof and an outlet port formed around the suction port; a motor provided in the housing and protruding downward from an output shaft that is rotationally driven around an axis extending in the vertical direction; a main plate fixed to the output shaft in the housing and extending radially outward of the axis; a turbofan which is mounted on a lower surface of the main plate in the housing at intervals in a circumferential direction, and which has an impeller that sends out air introduced from the suction port to an outside in a radial direction; and a heat exchanger provided in the casing so as to surround the turbo fan and through which air sent out from the turbo fan and directed toward the air outlet passes, the main plate including: a conical portion extending so as to expand radially outward as it goes upward; and a recessed portion formed so as to be recessed from the conical portion radially inward in the circumferential direction, the recessed portion being defined by a cylindrical plate portion extending along the axis and a disc plate portion extending radially outward from an upper end of the cylindrical plate portion, the cylindrical plate portion having an opening portion formed therein, the opening portion penetrating in the radial direction and allowing a circulating flow that comes out of the impeller and goes around to above the main plate to pass therethrough.

Advantageous effects

According to the present disclosure, it is possible to provide a ceiling embedded type air conditioner having a simpler configuration, the performance of which is further improved.

Drawings

Fig. 1 is a sectional view showing a configuration of a ceiling-embedded air conditioner according to an embodiment of the present disclosure.

Fig. 2 is a sectional view showing a structure of a main plate according to an embodiment of the present disclosure.

Fig. 3 is a side view showing the structure of the opening in the embodiment of the present disclosure.

Fig. 4 is a side view showing a modified example of the opening portion of the disclosed embodiment.

Fig. 5 is a side view showing another modified example of the opening portion according to the embodiment of the present disclosure.

Fig. 6 is a side view showing still another modified example of the opening portion according to the embodiment of the present disclosure.

Detailed Description

< first embodiment >

(construction of ceiling Embedded type air conditioner)

Hereinafter, a ceiling-embedded air conditioner 100 according to a first embodiment of the present disclosure will be described with reference to fig. 1 to 3. As shown in fig. 1, the ceiling-mounted air conditioner 100 includes a casing 1, a motor 2, a main plate 3, a turbo fan 4, a heat exchanger 5, and a bell mouth 6.

The housing 1 is embedded in a ceiling wall C of a building. The housing 1 is rectangular when viewed from below, and forms a space inside by being recessed toward above. Specifically, the casing 1 includes a panel 1A exposed on the ceiling surface Ca and a box-shaped cabinet 1B provided above the panel 1A. The panel 1A includes a panel body 11 as a rectangular frame and a grill 12 as an inlet 11A provided at the center of the lower portion. The panel body 11 forms an air outlet 11B around the air inlet 11A.

The motor 2 is provided inside the cabinet 1B at the center portion of the bottom surface 1S facing downward. The motor 2 includes a motor main body 21 accommodating a coil, a magnet, and the like, and an output shaft 22 vertically protruding downward from the motor main body 21. The output shaft 22 is rotationally driven about an axis Ac extending in the vertical direction.

A main plate 3 extending radially outward from the output shaft 22 is fixed to the output shaft 22. The structure of the main board 3 will be described later. A turbo fan 4 is mounted on the lower surface of the main plate 3. The turbofan 4 includes an impeller 41 including a plurality of blades arranged at intervals in a circumferential direction, and a disk-shaped shroud 42 covering the impeller 41 from below. The main plate 3 and the turbofan 4 rotate with the rotation of the output shaft 22, and send the air sucked from the suction port 11A to the outside in the radial direction.

An annular heat exchanger 5 surrounding the turbofan 4 is provided radially outside the turbofan 4. The heat exchanger 5 is a part of a refrigerant circuit having a refrigeration cycle. The air (main flow Fm) sent to the heat exchanger 5 by the turbofan 4 exchanges heat with the refrigerant while passing through the heat exchanger 5. Thus, the air flowing out of the outer peripheral side of the heat exchanger 5 is cooled air or heated air. The air flows downward along the side surface of the cabinet 1B and is supplied from the outlet 11B into the room.

A bell mouth 6 fixed to the upper portion of the panel body 11 is disposed below the turbofan 4. A bell mouth 6 is provided for guiding the air introduced from the suction port 11A and sending it to the turbo fan 4. The bell mouth 6 has a conical shape by gradually reducing its diameter from below to above.

(constitution of Main plate)

Next, the structure of the main board 3 will be described in detail with reference to fig. 2 and 3. As shown in fig. 2, the main plate 3 includes a bottom plate portion 31, a lower conical portion 32, a cylindrical plate portion 33, a disc plate portion 34, an upper conical portion 35, and an upper plate portion 36, which are integrally connected in this order from the radially inner side toward the radially outer side.

The bottom plate portion 31 is circular extending radially outward from the outer peripheral surface of the output shaft 22. A lower conical portion 32 is connected to an outer peripheral edge of the bottom plate portion 31. The lower conical portion 32 extends from the radially inner side to the radially outer side as going from the lower side to the upper side. That is, the lower conical portion 32 has a conical shape whose diameter increases gradually as it goes upward. The outer peripheral edge of the lower conical portion 32 is located below the motor main body 21.

A cylindrical plate portion 33 is connected to an outer peripheral edge of the lower conical portion 32. The cylindrical plate portion 33 is cylindrical with the axis Ac as the center. That is, the cylindrical plate portion 33 extends along the axis Ac when viewed in a cross-sectional view. The cylindrical plate portion 33 is formed with a plurality of openings h that penetrate the cylindrical plate portion 33 in the radial direction. As shown in fig. 3, the openings h are rectangular and arranged in a plurality at intervals in the circumferential direction. As shown in fig. 2, the opening h is formed at a position corresponding to the lower end of the motor main body 21 in the vertical direction.

A disc plate portion 34 is connected to an upper end edge of the cylindrical plate portion 33. The disc plate portion 34 expands radially outward from the upper end of the cylindrical plate portion 33. The disc plate portion 34 has an annular shape centered on the axis Ac. The cylindrical plate portion 33 and the disc plate portion 34 intersect at right angles in a cross-sectional view including the axis Ac. The term "right angle" as used herein means a substantially right angle, and design tolerances and manufacturing errors are included in the term "right angle". That is, the cylindrical plate portion 33 and the disc plate portion 34 may intersect at a slightly obtuse angle. The cylindrical plate 33 and the disc plate 34 define a recess R.

An upper conical portion 35 is connected to an outer peripheral edge of the disc plate portion 34. Like the lower conical portion 32, the upper conical portion 35 extends from the radially inner side to the radially outer side as going from the lower side to the upper side. That is, the lower conical portion 32 has a conical shape whose diameter increases gradually as it goes upward. Desirably, the lower conical portion 32 and the upper conical portion 35 are on the same conical surface as each other. An upper plate portion 36 is connected to an outer peripheral edge of the upper conical portion 35. The upper plate portion 36 has an annular shape spreading radially outward from the outer peripheral edge of the upper conical portion 35. The impeller 41 of the turbofan 4 is attached to the lower surfaces of the upper plate portion 36 and the upper conical portion 35. In fig. 2, the impeller 41 is not shown.

(Effect)

Next, the operation of the ceiling-mounted air conditioner 100 will be described. In operating the ceiling-embedded air conditioner 100, the motor 2 is first driven. By driving the motor 2, the output shaft 22, the main plate 3, and the turbofan 4 are rotated about the axis Ac. The turbo fan 4 rotates to take in indoor air from the intake port 11A. This air is sent to the turbofan 4 through the bellmouth 6, and then is forced outward in the radial direction, thereby forming a main flow Fm (see fig. 1 or 2). The main flow Fm flows along the lower surface of the main plate 3. That is, the main flow Fm flows from the radially inner side to the radially outer side as going from the lower side to the upper side. Most of the main flow Fm passes through the heat exchanger 5 to exchange heat with the refrigerant, and is supplied as cold air or warm air from the air outlet 11B into the room.

On the other hand, a part of the main flow Fm flows so as to bypass above the main plate 3 without going toward the heat exchanger, thereby forming a circulating flow Fc. The circulating flow Fc flows toward the inner peripheral side along the upper surface of the main plate 3, and is then blown to the motor main body 21, thereby cooling the motor main body 21. The circulating flow Fc that has cooled the motor main body 21 flows downward, and then merges with the main flow Fm on the lower surface side of the main plate 3 through the opening h formed in the main plate 3.

Here, when the angle at which the main flow Fm merges with the circulating flow Fc approaches a right angle, a mixing loss occurs between the two. As a result, the air cannot flow smoothly in the casing 1, and the performance of the air conditioner may be affected. Therefore, in the present embodiment, the main plate 3 is formed with the recess R, and the cylindrical plate portion 33 defining the recess R is formed with the opening h.

According to the above configuration, the cylindrical plate portion 33 having the opening h extends along the axis Ac. Thereby, the circulating flow Fc is blown out radially outward from the opening h. Here, the main flow Fm flows upward as it goes radially outward. Since the circulating flow Fc is blown out radially outward, the angle at which the main flow Fm merges with the circulating flow Fc can be reduced. As a result, the mixing loss generated between the main flow Fm and the circulating flow Fc can be suppressed to be small. In the above configuration, such a reduction in mixing loss can be achieved by forming the recessed portion R only in the main plate 3 without increasing the number of components. This can improve the performance of the ceiling-mounted air conditioner 100 while suppressing an increase in manufacturing cost.

(other embodiments)

The embodiments of the present disclosure have been described above. It is to be noted that various changes and modifications can be made to the above-described configuration without departing from the gist of the present disclosure. For example, in the above-described embodiment, an example is described in which the opening h has a rectangular shape and a plurality of openings are arranged at intervals in the circumferential direction. However, the configurations shown in fig. 4 to 6 may also be employed.

In the example of fig. 4, the positions of the openings h2 adjacent to each other in the direction of the axis Ac are different. The circumferential end portions t1 of the openings h2 overlap each other in the vertical direction.

According to the above configuration, the circulating flow Fc can be guided without being deviated over the entire circumferential region. As a result, the pressure loss at the opening h2 can be further reduced. Further, the decrease in the strength of the main plate due to the formation of the plurality of openings h2 can be suppressed to a small extent. As a result, the durability of the ceiling-mounted air conditioner 100 can be further improved.

In the example of fig. 5, the circumferential end edge L1 of the opening portion h3 extends in a direction inclined with respect to the axis Ac, and these end edges L1 of the opening portions h3 adjacent to each other overlap each other in the vertical direction. The same operational effects as those of the example of fig. 4 can be obtained by this configuration.

In the example of fig. 6, the opening h4 is formed in a row by arranging a plurality of openings at intervals in the circumferential direction, and has a plurality of (two) rows R1 and R2 at intervals in the vertical direction. The positions of the openings h4 in the circumferential direction of the rows adjacent to each other in the vertical direction are different from each other. The same operational effects as those of the examples of fig. 4 and 5 can be obtained by this configuration.

< accompanying notes >

The ceiling-embedded air conditioner 100 described in each embodiment is grasped, for example, as follows.

(1) The ceiling-mounted air conditioner 100 according to the first aspect includes: a casing 1 having a suction port 11A formed at the lower center thereof and an air outlet 11B formed around the suction port 11A; a motor 2 provided in the housing 1 and protruding downward around an output shaft 22 that is rotationally driven about an axis Ac extending in the vertical direction; a main plate 3 fixed to the output shaft 22 in the housing 1 and extending radially outward of the axis Ac; a turbo fan 4 mounted on a lower surface of the main plate 3 at intervals in a circumferential direction in the casing 1, and having an impeller 41 that sends out air introduced from the inlet 11A to an outside in a radial direction; and a heat exchanger 5 provided in the casing 1 so as to surround the turbo fan 4 and through which air sent out from the turbo fan 4 toward the air outlet 11B passes, the main plate 3 including: conical portions 32, 35 extending so as to expand radially outward as they go upward; and a recessed portion R formed so as to be recessed inward in the radial direction from the conical portions 32 and 35 in the circumferential direction, the recessed portion R being defined by a cylindrical plate portion 33 and a disc plate portion 34, the cylindrical plate portion 33 extending along the axis Ac, the disc plate portion 34 extending from an upper end of the cylindrical plate portion 33 outward in the radial direction, and the cylindrical plate portion 33 being formed with an opening h that penetrates in the radial direction and through which a circulation flow Fc that comes out of the impeller 41 and goes around to above the main plate 3 passes.

According to the above configuration, the cylindrical plate portion 33 having the opening h extends along the axis Ac. Thereby, the circulating flow Fc is blown out radially outward from the opening h. Here, a main flow Fm flowing upward along the main plate 3 is formed outside the main plate 3. More specifically, the main flow Fm flows upward as it goes radially outward. As described above, the circulating flow Fc is blown out radially outward, and therefore the angle at which the main flow Fm merges with the circulating flow Fc can be reduced. As a result, the mixing loss generated between the main flow Fm and the circulating flow Fc can be suppressed to be small. In the above configuration, such a reduction in mixing loss can be achieved by forming the recessed portion R only in the main plate 3 without increasing the number of components. This can improve the performance of the ceiling-mounted air conditioner 100 while suppressing an increase in manufacturing cost.

(2) In the ceiling-mounted air conditioner 100 according to the second aspect, the plurality of opening portions h2 are arranged in the circumferential direction, and the circumferential end portions t1 of the opening portions h2 adjacent to each other overlap each other in the vertical direction.

With the above configuration, a plurality of the openings h2 are arranged in the circumferential direction, and the circumferential end t1 of the adjacent openings h2 vertically overlap. This can guide the circulating flow so as not to be deviated over the entire circumferential region. As a result, the pressure loss at the opening h2 can be further reduced.

(3) In the ceiling-mounted air conditioner 100 according to the third aspect, the opening h2 has a rectangular shape with the longitudinal direction in the circumferential direction, and the positions of the adjacent openings h2 in the vertical direction are different.

According to the above configuration, the opening h2 has a rectangular shape, and the positions of the adjacent openings h2 in the vertical direction are different. This can guide the circulating flow Fc over the entire circumferential region without being skewed, and can also reduce the decrease in strength of the main plate 3 due to the formation of the plurality of openings h 2. As a result, the durability of the ceiling-mounted air conditioner 100 can be further improved.

(4) In the ceiling-mounted air conditioner 100 according to the fourth aspect, the circumferential end edges L1 of the opening portions h3 extend in a direction inclined with respect to the axis Ac, and the end edges L1 of the opening portions h3 adjacent to each other overlap in the vertical direction.

According to the above configuration, the circumferential end edges L1 of the opening portion h3 are inclined, and the adjacent end edges L1 overlap each other in the vertical direction. This allows the circulating flow Fc to be guided without being skewed over the entire circumferential area.

(5) In the ceiling-embedded air conditioner 100 of the fifth aspect, the opening h4 has a plurality of rows R1 and R2 formed by arranging a plurality of rows at intervals in the circumferential direction, and has a plurality of rows R1 and R2 at intervals in the vertical direction, and the positions of the openings h4 in the circumferential direction of the rows R1 and R2 adjacent to each other in the vertical direction are different from each other.

According to the above configuration, the plurality of openings h4 are arranged in the circumferential direction and the vertical direction, and the positions of the openings h4 in the circumferential direction are different between the rows R1 and R2 adjacent to each other in the vertical direction. This can guide the circulating flow Fc over the entire circumferential region without being skewed, and can also reduce the decrease in strength of the main plate 3 due to the formation of the plurality of openings h 4. As a result, the durability of the ceiling-mounted air conditioner 100 can be further improved.

Description of the symbols

100 ceiling embedded air conditioner

1 casing

1A panel

1B machine cabinet

1S bottom surface

2 Motor

3 mainboard

4 turbo fan

5 Heat exchanger

6 bell mouth

11 Panel body

11A suction inlet

11B air outlet

12 grid

21 Motor body

22 output shaft

31 bottom plate part

32 lower conical part

33 cylindrical plate part

34 disc plate part

35 upper conical part

36 upper plate part

41 impeller

42 shield

Ac axis

Fc recycle streams

Fm mainstream

h. h2, h3, and h4 openings

L1 end edge

R recess

Columns R1 and R2

t1 circumferential end

Claims

1. A ceiling-embedded air conditioner is provided with:

a casing having a suction port formed at the lower center thereof and an outlet port formed around the suction port;

a motor provided in the housing and protruding downward from an output shaft that is rotationally driven around an axis extending in the vertical direction;

a main plate fixed to the output shaft in the housing and extending radially outward of the axis;

a turbofan which is mounted on a lower surface of the main plate in the housing at intervals in a circumferential direction, and which has an impeller that sends out air introduced from the suction port to an outside in a radial direction; and

a heat exchanger provided in the casing so as to surround the turbofan and through which air sent out from the turbofan and directed toward the air outlet passes,

the main board has:

a conical portion extending so as to expand radially outward as it goes upward; and

a recessed portion formed so as to be recessed from the conical portion radially inward in the circumferential direction, the recessed portion being defined by a cylindrical plate portion extending along the axis and a disc plate portion extending radially outward from an upper end of the cylindrical plate portion,

an opening portion is formed in the cylindrical plate portion, and the opening portion penetrates in the radial direction and is penetrated by a circulating flow which comes out of the impeller and goes around to the upper side of the main plate.

2. The ceiling-embedded air conditioner of claim 1,

a plurality of the opening parts are arranged in the circumferential direction,

circumferential end portions of the opening portions adjacent to each other overlap each other in the vertical direction.

3. The ceiling-embedded air conditioner of claim 1 or 2,

the openings are rectangular with the circumferential direction being the longitudinal direction, and the positions of the openings adjacent to each other in the vertical direction are different.

4. The ceiling-embedded air conditioner of claim 1 or 2,

the peripheral end edges of the opening portions extend in a direction inclined with respect to the axis, and the end edges of the adjacent opening portions overlap each other in the vertical direction.

5. The ceiling-embedded air conditioner of claim 1,

the opening portions are arranged in a plurality of rows at intervals in the circumferential direction, and the plurality of rows are provided at intervals in the vertical direction, and the positions of the opening portions in the circumferential direction of the adjacent rows in the vertical direction are different from each other.

6. The ceiling-embedded air conditioner of claim 2,

7. The ceiling-embedded air conditioner of claim 3,

8. The ceiling-embedded air conditioner of claim 4,