JP4570048B2 - Air conditioner indoor unit - Google Patents

Description

  The present invention relates to an indoor unit of an air conditioner, and particularly suitable for an indoor unit of an air conditioner that sucks indoor air with a turbo fan and blows it to an indoor heat exchanger to cool or heat the air and blow it out indoors. It is.

  A general air conditioner has a refrigerant circulation channel in which a refrigerant is enclosed, a compressor that compresses the refrigerant, an indoor heat exchanger that exchanges heat between the refrigerant and indoor air, an expansion valve that depressurizes the refrigerant, A refrigeration cycle in which an outdoor heat exchanger for exchanging heat between the refrigerant and the outside air is sequentially provided. Among these, the indoor heat exchanger is stored in the housing of the indoor unit together with a blower that sends room air to the indoor heat exchanger. There are various types of such indoor units, but in recent years, especially in the field of business use, the casing is embedded in the ceiling, and air is sucked and blown through a decorative panel installed on the ceiling surface. The so-called ceiling-embedded cassette type is the mainstream.

  An example of a conventional air conditioner indoor unit will be described with reference to FIGS. 6 is a longitudinal sectional view of a conventional indoor unit of an air conditioner, and FIG. 7 is an enlarged view of a turbo fan used in FIG.

  The indoor unit 30 includes a turbo fan 7 in which a plurality of blades 16 are provided between a shroud 24 having a suction opening 25 and a hub 14 having an arcuate flow path surface, and the turbo fan 7 disposed on the back side of the hub 14. The fan motor 6 to be driven, the indoor heat exchanger 11 that exchanges heat between the air sent from the turbo fan 7 and the refrigerant passing through the inside, and the housing 2 that houses the turbo fan 7, the fan motor 6, and the indoor heat exchanger 11. And is configured. A plurality of cooling holes 20 are provided in a portion of the hub 14 located on the suction side of the blade 16. In the turbofan 7, the hub 14 and the blade 16 are integrally molded with resin, and then the blade 16 is joined to the shroud 24 by ultrasonic welding.

  In the indoor unit 30, when the turbo fan 7 is operated, the pressure on the fan blowing side becomes higher than the pressure on the fan suction side. Therefore, a part of the air blown out from the turbo fan 7 is caused by the pressure difference and the arrow 15 in FIG. As shown in FIG. 5, air flows backward from the rear surface of the hub (the upper surface of the turbofan 7 in FIG. 5) to the inlet side of the blade 16 through the cooling hole 20. The backflowing air passes around the motor 6 to cool the fan motor 6.

  In addition, as what concerns a prior art, Unexamined-Japanese-Patent No. 2004-156886 (patent document 1) is mentioned, for example.

JP 2004-156886 A

  The above-described turbofan 7 is easy to manufacture because the hub 14 and the blade 16 can be manufactured integrally, and is widely used. However, the blade 16 inevitably has a limitation for removing the mold, A three-dimensional free shape could not be obtained. For this reason, the fan performance of the turbo fan 7 cannot be improved, and there has been a problem that the noise reduction and the energy saving performance cannot be sufficiently achieved.

  In recent years, the need for quietness and energy saving for air conditioners has been increasing, and in order to obtain fan performance that meets these demands, it is required to make the blade shape a fluidly optimal three-dimensional blade. . Therefore, it is conceivable to simplify the joining of the hub and the blade while making the three-dimensional blade possible by manufacturing the blade and the hub separately and joining them by laser welding.

  When the wing and the hub are separately molded and both are laser-welded, it is necessary to bring the joint surfaces of the wing and the hub into close contact with each other with high accuracy. However, in pursuit of the performance of the turbofan, it is desirable that the meridional surface formed by the hub has an arc shape along the streamline. This is extremely difficult in practice, and it has been difficult to obtain a highly reliable joint.

  Accordingly, as shown in FIGS. 8 to 10, a groove 26 for fitting the blade 16 is provided on the inner side to form a plurality of projecting portions 18 projecting back from the arc-shaped flow path surface of the hub 14, and It is conceivable that the end face of the blade 16 to be fitted and the bottom face of the groove 26 are laser welded as a flat face that matches each other. However, when the turbo fan 7 is rotated by the motor 6, the back side of the hub 14 has the air flow 15 for cooling the motor 6 as described above. On the other hand, an outward air flow is generated by the protrusion 18. The air flow caused by the protrusion 18 interferes with the air flow 15 for cooling the motor 6, and air turbulence 19 is generated. As a result, noise is generated, and the resistance of the air flow 15 for cooling the motor 6 becomes a resistance, so that extra power is required and the cooling efficiency of the motor 6 is lowered.

  The objective of this invention is providing the indoor unit of the air conditioner excellent in reliability, silence, and energy-saving property.

  To achieve the foregoing object, the present invention provides a turbofan having a plurality of blades joined between a shroud having a suction opening and a hub having an arcuate flow path surface, and the turbofan disposed on the back side of the hub. A fan motor for driving the fan, an indoor heat exchanger for exchanging heat between the air sent from the turbo fan and the refrigerant passing through the interior, and a housing housing the turbo fan, the fan motor, and the indoor heat exchanger; The air conditioner indoor unit is provided with a cooling hole communicating with the back side of the hub in a portion located on the suction side of the hub of the hub, A plurality of projecting portions projecting from the arc-shaped flow path surface of the hub to the back side are formed, and a closing portion is formed so as to close a gap formed between the plurality of projecting portions. Structure with It lies in the thing.

A preferred specific configuration example of the present invention is as follows.
(1) The closing portion is configured by a ring-shaped disk provided so as to close an upper surface of a gap formed between the plurality of protruding portions.
(2) The end surface of the blade fitted into the groove and the bottom surface of the groove are laser welded as flat surfaces that match each other.
(3) The closing portion is provided so as to close a side surface of a gap formed between the plurality of protruding portions.
(4) The closing portion is constituted by a partition wall portion formed integrally and projecting from the hub to the back side.
(5) The partition wall portion has substantially the same height as the end portion on the fan shaft center side of the protruding portion, and is formed so as to connect these end portions linearly.

  ADVANTAGE OF THE INVENTION According to this invention, the indoor unit of the air conditioner excellent in reliability, silence, and energy saving is obtained.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol in FIGS. 1-10 shows the same thing or an equivalent. In the following embodiments, an example of an indoor unit of a ceiling-embedded cassette type air conditioner will be described, but the present invention is applicable to all indoor units of an air conditioner using a turbofan.
(First embodiment)
An indoor unit of an air conditioner according to a first embodiment of the present invention will be described with reference to FIGS. 1 is a longitudinal sectional view of an indoor unit of an air conditioner according to a first embodiment of the present invention, FIG. 2 is an enlarged view of the turbo fan of FIG. 1, and FIG. 3 is a plan view of the turbo fan of FIG.

  The air conditioner according to the present embodiment includes an indoor unit 30, an outdoor unit, and piping and wiring that connect them, and the casing of the indoor unit 30 is embedded in the ceiling and the decorative panel 1 installed on the ceiling surface. This is a ceiling-embedded cassette type that sucks air through, cools or heats and blows it into the room. The air conditioner includes a compressor that compresses a refrigerant in a refrigerant circulation channel in which the refrigerant is sealed, an indoor heat exchanger 11 that exchanges heat between the refrigerant and indoor air, an expansion valve that depressurizes the refrigerant, and a refrigerant And an outdoor heat exchanger for exchanging heat with the outside air are sequentially provided.

  As shown in FIG. 1, the indoor unit 30 includes a decorative panel 1, a housing 2, a suction grill 3, a blowout louver 4, a fan motor 6, a turbo fan 7, a filter 9, a bell mouth 10, an indoor heat exchanger 11, a drain pan. 12 and an electrical component box 13 are provided.

  The decorative panel 1 is generally formed in a substantially flat rectangular shape, and a suction port 27 is provided at the center thereof, and a blowout port 5 is provided around the suction port 27. The suction grill 3 is detachably attached to the suction port 27 of the decorative panel 1. A filter 9 is detachably mounted inside the suction grill 3. A bell mouth 10 is installed on the inner upper side of the filter 10. A blowout louver 4 is installed at the blowout opening 5 of the decorative panel 1.

  The casing 2 is formed in a square box shape with the lower surface opened, and the decorative panel 1 is attached so as to cover the opening of the lower surface. The housing 2 accommodates a fan motor 6, a turbo fan 7, a bell mouth 10, an indoor heat exchanger 11, a drain pan 12, and an electrical component box 13 therein, and sucks room air from the center of the lower surface, It has an air passage that blows out from the section.

  As shown in FIGS. 1 to 3, the turbofan 7 includes a shroud 24, a blade 16, a hub 14, and a ring-shaped disk 21. The turbofan 7 includes a shroud 24 having a suction opening 25, a hub 14 having an arcuate flow path surface 14 a, and a plurality of blades 16 joined between the both 24 and 14. In addition, the turbo fan 7 is installed at the central portion in the housing 2 so as to suck room air from the center of the lower surface and blow it out from the outer periphery of the side surface.

  The shroud 24 has a disc ring shape as a basic shape, and is disposed so as to be opposed to the top of the bell mouth 10 and has a suction opening 25 corresponding to the central opening 28 of the bell mouth 10. The shroud 24 is made of resin.

  The hub 14 has a disk shape as a basic shape, and includes a boss 17 provided at the center, and a flow path portion having an arc-shaped flow path surface 14a that has an arc shape along a streamline of room air. . The hub 14 is made of resin. A plurality of cooling holes 20 communicating with the back side of the hub 14 are provided in a portion of the hub 14 located on the suction side from the blade 16. The cooling holes 20 are for cooling the fan motor 6 and are provided around the boss 17 at equal intervals.

  A plurality of projecting portions 18 projecting to the back side are formed in the channel portion constituting the arc-shaped channel surface 14 a of the hub 14. A groove 26 for fitting the wing 16 is provided inside the protrusion 18. The end face of the blade 16 fitted in the groove 26 and the bottom face of the groove 26 are formed as flat surfaces that match each other, and are joined by laser welding.

  A ring-shaped disk 21 is provided on the back side of the hub 14 so as to close gaps formed between the plurality of protrusions 18. The ring-shaped disk 21 constitutes a closing portion that closes the upper surface of the gap formed between the plurality of protruding portions 18. The ring-shaped disk 21 may be bonded or welded to the hub 14 and may be joined so as to rotate integrally with the hub 14 and the protrusion 18.

  The blade 16 is formed in a three-dimensional blade shape that is fluidly optimal in order to obtain fan performance that meets quietness and energy saving. The blade 16 is made of resin.

  The fan motor 6 that drives the turbofan 7 is disposed between the hub 14 and the upper wall of the housing 2. A boss 17 of the hub 14 is fixed to the lower end portion of the rotating shaft extending downward from the fan motor 6. The hub 14 is rotated with the rotation of the rotation shaft of the fan motor 6, and the turbo fan 7 is rotated.

  The indoor heat exchanger 11 is arranged so as to surround the turbo fan 7 and is configured to exchange heat between the air sent from the turbo fan and the refrigerant passing through the inside. A drain pan 12 is installed below the indoor heat exchanger 11 to receive dew condensation water generated in the indoor heat exchanger 11 during cooling. The collected condensed water is discharged to the outside through the water pipe.

  On a part of the lower surface of the bell mouth 10, an electrical component box 13 containing a control board for controlling the operation of the air conditioner is installed.

  Next, the operation of the indoor unit 30 will be described. By operating the air conditioner and driving the motor 6 installed in the housing 2 to rotate the turbofan 7 connected to the shaft of the motor 6, the indoor air is as shown by the arrow 8 in FIG. Then, the air is sucked into the turbo fan 24 in the housing 2 through the suction grill 3, the filter 9, and the bell mouth 10. The room air sucked into the turbo fan 7 is boosted by the turbo fan 7 and then blown outside the outer periphery of the turbo fan 7.

  Most of the indoor air blown out from the turbofan 7 passes through the indoor heat exchanger 11 as shown by an arrow 16 in FIG. 1 and is cooled during the cooling operation and heated during the heating operation. The air is blown into the room from the blowout port 5. Thereby, indoor air conditioning is performed.

  Further, a part of the indoor air blown out from the turbo fan 7 passes through the back side of the turbo fan 7, that is, between the turbo fan 7 and the housing 2, as shown by an arrow 15 in FIGS. The fan motor 6 is cooled and backflowed to the inlet side of the blade 16 through the cooling hole 20. That is, when the turbo fan 7 is operated, the pressure on the fan blowing side becomes higher than the pressure on the fan suction side, so that a part of the air blown out from the turbo fan 7 is separated from the hub side (turbo fan 7 by the pressure difference). The cooling hole 20 flows back to the inlet side of the blade 16.

  Since the motor cooling air flow 15 is guided by the ring disk 21 and guided around the fan motor 6, the fan motor 6 can be efficiently cooled. Further, since the ring-shaped disk 21 is provided so as to close the upper surface of the gap formed between the plurality of protrusions 18, the flow of air to the outer periphery due to the rotation of the protrusions 18 does not occur. The motor cooling air flow 15 is not disturbed. As a result, generation of noise due to the motor cooling air flow 15 can be prevented, fan efficiency can be further improved, and the fan motor 6 can be efficiently cooled.

  According to this embodiment, since the hub 14 has the arcuate flow path surface 4a, the streamline of the indoor air sucked into the turbofan 7 is along the arcuate flow path surface 4a. As a result, the fan performance can be improved as compared with the case of a hub formed with a simple flat flow path surface.

  Further, the bottom surface of the groove 26 provided inside the protrusion 18 and the end surface of the blade 16 fitted in the groove 26 are formed as flat surfaces that match each other and are joined by laser welding. It is possible to easily obtain a highly reliable joint while improving fan performance by using 16 as a three-dimensional shape.

  Furthermore, since the cooling hole 20 is provided on the blade suction side of the hub 14 and the ring-shaped disk 21 is provided so as to close the upper surface of the gap formed between the plurality of protrusions 18, the noise caused by the motor cooling air The fan motor 6 can be efficiently cooled while suppressing the above.

In this embodiment, the indoor unit of the air conditioner excellent in reliability, silence, and energy saving can be obtained by these.
(Second Embodiment)
Next, an indoor unit of an air conditioner according to a second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a plan view of a turbo fan used in an indoor unit of an air conditioner according to a second embodiment of the present invention. The second embodiment is different from the first embodiment in the points described below, and the other points are basically the same as those in the first embodiment, so that the duplicate description is omitted.

  In the second embodiment, a cylindrical wall portion 22 having substantially the same height as the protruding portion 18 is in contact with the inner peripheral side of the protruding portion 18 on the fan shaft center side of the protruding portion 18 on the rear surface of the hub 14 of the turbofan 7. Has been placed. The cylindrical wall portion 22 constitutes a closing portion that closes a side surface on the fan shaft center side of a gap formed between the plurality of projecting portions 18. The cylindrical wall portion 22 is constituted by a partition wall portion formed so as to protrude integrally from the hub 14 to the back side.

  When this air conditioner is operated and the turbo fan 7 is rotated, a part of the air blown from the turbo fan 7 passes through the back surface of the hub 14 to cool the fan motor 6 and the blades through the cooling holes 20. Backflow to the inlet side. Here, since the cylindrical wall portion 22 is provided inside the protruding portion 18, the flow of air outward from the outer periphery due to the rotation of the protruding portion 18 does not occur, and the flow 15 of the motor cooling air is not disturbed. As a result, the generation of noise due to the motor cooling air flow 15 can be prevented, the fan efficiency can be further improved, and the fan motor 6 can be efficiently cooled.

Further, the cylindrical wall portion 22 may be molded integrally with the hub 14 when the hub 14 is molded, and there is no need to add a ring-shaped disk 21 as a new part as in the first embodiment, and the hub Since the weight of the material added to 14 can be reduced, the cost can be reduced.
(Third embodiment)
Next, an indoor unit of an air conditioner according to a third embodiment of the present invention will be described with reference to FIG. FIG. 5 is a plan view of a turbo fan 7 used in an indoor unit of an air conditioner according to a third embodiment of the present invention. The third embodiment is different from the second embodiment in the following points, and the other points are basically the same as those in the second embodiment, and thus redundant description is omitted.

  In the third embodiment, the partition wall portion 23 is formed so as to have substantially the same height as the end portion of the protruding portion 18 on the fan shaft side and to connect these end portions linearly. Even with such a configuration, the same effect as that of the second embodiment is obtained, and the protrusion 18 is connected in a straight line. Therefore, the weight of the turbofan 7 can be further reduced as compared with the second embodiment.

  In order to reduce noise and power, it is preferable to use the partition wall portion 23 that connects the end portion on the fan shaft center side of the protruding portion 18 as in the third embodiment, but other than the end portion of the protruding portion 18. Even if it is provided between the protrusions and the intermediate side surface of the gap formed between the plurality of protrusions 18 is closed, a certain degree of effect can be expected. In that case, the length of the partition wall portion 23 can be shortened, and the weight of the turbofan 7 can be further reduced as compared with the third embodiment.

It is a longitudinal section of the indoor unit of the air harmony machine concerning a 1st embodiment of the present invention. It is an enlarged view of the turbo fan of FIG. It is a top view of the turbo fan of FIG. It is a top view of the turbo fan used for the indoor unit of the air conditioner of 2nd Embodiment of this invention. It is a top view of the turbo fan used for the indoor unit of the air conditioner of 3rd Embodiment of this invention. It is a longitudinal cross-sectional view of the indoor unit of the conventional air conditioner. It is an enlarged view of the turbo fan used for FIG. It is a longitudinal cross-sectional view of the indoor unit of the air conditioner which concerns on the comparative example of this invention. It is an enlarged view of the turbo fan of FIG. It is a top view of the turbo fan of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Cosmetic panel, 2 ... Housing, 3 ... Suction grill, 4 ... Louver, 5 ... Outlet, 6 ... Motor, 7 ... Turbo fan, 8 ... Flow of suction air, 9 ... Filter, 10 ... Bell mouth, 11 ... indoor heat exchanger, 12 ... drain pan, 13 ... electrical box, 14 ... hub, 14a ... arc-shaped flow path surface, 15 ... flow of motor cooling air, 16 ... blade, 17 ... boss, 18 ... protrusion, 19 ... Air turbulence, 20 ... cooling hole, 21 ... ring disk (blocking portion), 22 ... cylindrical wall portion (blocking portion), 23 ... partition wall portion (blocking portion), 24 ... shroud, 25 ... suction opening, 26 ... Groove, 27 ... Suction port, 28 ... Central opening, 30 ... Indoor unit.

Claims (6)

A turbofan having a plurality of blades joined between a shroud having a suction opening and a hub having an arcuate flow path surface;
A fan motor disposed on the back side of the hub to drive the turbofan;
An indoor heat exchanger for exchanging heat between the air sent from the turbofan and the refrigerant passing through the interior;
The turbofan, the fan motor, and a housing that houses the indoor heat exchanger are configured,
An indoor unit of an air conditioner configured by providing a cooling hole communicating with the back side of the hub in a portion located on the suction side of the blade of the hub,
A plurality of projecting portions projecting from the arc-shaped flow path surface of the hub to the back side are provided with grooves for fitting the wings inside,
Providing a closing part so as to close a gap formed between the plurality of protruding parts;
An air conditioner indoor unit.   The indoor unit of an air conditioner according to claim 1, wherein the closing part is configured by a ring-shaped disk provided so as to close an upper surface of a gap formed between the plurality of protruding parts. An air conditioner indoor unit.   2. The air conditioner indoor unit according to claim 1, wherein the end surface of the blade fitted in the groove and the bottom surface of the groove are laser welded as a flat surface that matches each other. The indoor unit of the harmony machine.   The air conditioner indoor unit according to claim 1, wherein the closing portion is provided so as to close a side surface of a gap formed between the plurality of protrusions. Indoor unit.   5. The indoor unit of an air conditioner according to claim 4, wherein the closing portion is constituted by a partition wall portion that is integrally formed so as to protrude rearward from the hub. . 6. The indoor unit of an air conditioner according to claim 5, wherein the partition wall portion has substantially the same height as an end portion of the protruding portion on the fan shaft center side, and linearly connects these end portions. An air conditioner indoor unit characterized by being formed as described above.

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