JP2730395B2 - Air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Generally, in a centrifugal fan-type blower, a centrifugal acceleration action (or a mixed flow acceleration action) of a blade applied to a fluid is given.
Is used to realize a blowing function, so that the efficiency of transferring and converting kinetic energy to a fluid such as air is extremely high. For example, it has been widely used as a blower for an air conditioner.

[0003] Recently, as a type of air conditioner, an air conditioner embedded in a ceiling has been increasingly used, particularly from the viewpoint of the advantage of the installation space and the freedom of the indoor design, and such a ceiling has been increased. In an embedded type air conditioner, for example, a centrifugal fan or a kind of mixed flow fan is used among various blowers in view of its wind direction conversion function as disclosed in Japanese Patent Application Laid-Open No. 62-194128. Is customary. Therefore, the following description will be made on the case where a centrifugal fan is used.

[0004] In recent years, there has been an increasing demand for smaller and more compact air conditioners, and the diameter of a generally annular heat exchanger often used in the above-described ceiling-mounted air conditioners tends to be smaller. . Therefore,
Since the heat exchange capacity is reduced by the reduced diameter, it is necessary to cover the reduced capacity by increasing the height of the heat exchanger. In response to the increase in height of the heat exchanger, the axial speed of the impeller is increased to improve the wind speed distribution of the airflow passing through the heat exchanger.

As shown in FIGS. 19 and 20, a conventional centrifugal centrifugal fan includes a hub 1 which is opposed to the hub 1 at a predetermined interval and a shroud 2 having a fan suction port 4 at the center thereof. Are arranged radially, and each of the blades 3 has a front edge 3a and a rear edge 3b of the blade 3.
Is usually formed in a two-dimensional shape orthogonal to the hub 1 and the shroud 2 (or the front edge 3a is inclined in the rotation direction).

In the case of the impeller having the blades 3 having the above-described shape, as shown in FIG. 20, the direction of the force F applied to the air flow by the positive pressure surface 3c of the blades 3 is different from that of the hub 1 and the shroud 2. Because of the parallel position, the separation flow E is likely to be generated near the outlet on the shroud 2 side where the wind speed increases. Then, since the wind speed distribution of the air flow blown from the centrifugal fan is biased toward the hub 1, the ventilation resistance increases and the operating noise increases. This tendency increases as the axial length of the blade 3 increases.

As a result, the heat exchange efficiency of the heat exchanger deteriorates, the fan power increases due to the increase in the internal resistance, and the heat transfer performance deteriorates, and the energy efficiency decreases. .

In order to suppress the separation flow generated in the vicinity of the shroud-side outlet as described above, the present inventors disclosed in Japanese Patent Application No. 3-194395 as shown in FIGS. the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of proposes that allowed a predetermined amount offset in the reverse rotation direction from the position of the hub-side coupling part 3b _1. With this configuration, as shown in FIG. 22, since the trailing edge side of the pressure surface 3c of the blade 3 is inclined, the force F acting on the airflow by the pressure surface 3c is reduced by the shroud 2. become a direction (i.e., the force component F ₁ to the shroud 2 direction is generated), separated flow occurs at the exit side of the shroud 2 side of the blade 3 is prevented.

[0009]

[SUMMARY OF THE INVENTION However, as described above, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, a predetermined amount in a counter-rotational direction than the position of the hub-side coupling part 3b ₁ When the camber line C of the blade 3 is formed into a single arc shape as conventionally used in the case of offsetting, the chord length Ls near the shroud 2 is changed to the chord length near the hub 1 as shown in FIG. If the blade outlet angle near the shroud 2 is βs and the blade outlet angle near the hub 1 is βh, βs << βh because the length is longer than the length Lh.

The total pressure head of the blade 3 is given by Ht = (1 / g) · u ₂ · Ve. Here, g: gravitational acceleration, u ₂ : blade outer peripheral velocity, Ve: circumferential component of the blowing flow.

On the other hand, there is a fact that the circumferential component Ve of the blowing flow increases as the blade outlet angle β increases.

Therefore, as described above, in the case of the blade shape satisfying βs << βh, the full pressure head H of the blade element near the shroud is used.
Comparing (s) t with the total pressure head H (h) t of the blade element near the hub, H (s) t << H (h) t, and (shroud side wind speed) << (hub side Wind speed). In other words, there is a possibility that the drift of the flow of air from the impeller to the hub side cannot be sufficiently suppressed, and there are cases where an increase in ventilation resistance and an increase in driving noise cannot be eliminated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and has the object of rectifying the airflow at the outlet of the impeller to make the wind speed distribution of the air passing through the heat exchanger uniform. The purpose is to do so.

[0014]

According to the first aspect of the present invention, as a means for solving the above-mentioned problems, as shown in the drawings, the casing extends between the outer peripheral portions of the hub 1 and the shroud 2 in the casing 10. A centrifugal fan 12 having a plurality of blades 3, 3,... And having an impeller 11 having a fan suction port 4 formed in the center of the shroud 2 is located on the blowout side of the centrifugal fan 12. A substantially annular heat exchanger 13 is provided, and the casing 10 is provided with an air suction port 15 facing the fan suction port 4, and air that blows conditioned air after passing through the heat exchanger 13 into the room. In the air conditioner having the air outlet 16, the rear edge 3 of each of the blades 3 is provided.
The position of the shroud-side coupling portion 3b ₂ at b, together with allowed to a predetermined amount offset in the counter-rotational direction of the impeller 11 than the position of the hub-side coupling part 3b _1, wherein the rear edge 3 of each blade 3
The hub-side blade exit angle βh and the shroud-side blade exit angle βs at b are substantially equal.

According to the second aspect of the present invention, as a means for solving the above problems, as shown in the drawings, a casing 10 is provided.
Inside, there is provided an impeller 11 having a plurality of blades 3 extending across the outer peripheral portions of the hub 1 and the shroud 2 and having a fan suction port 4 formed in the center of the shroud 2. A centrifugal fan 12 and a substantially annular heat exchanger 13 located on the blowout side of the centrifugal fan 12, and an air inlet 15 facing the fan inlet 4 in the casing 10, in the air conditioning apparatus to form an air outlet 16 for blowing out the conditioned air after passing through the heat exchanger 13 to the indoor, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, the hub-side together allowed to a predetermined amount offset in the counter-rotational direction of the impeller 11 than the position of the coupling portion 3b _1, wherein the pressure side with formed convex of the shroud side blade element of each vane 3, the maximum camber line Cs of the shroud side blade element Anti Position is allowed positioned in front edge side chord length intermediate position Csmax.

According to the third aspect of the present invention, as a means for solving the above problems, as shown in the drawings, a casing 10 is provided.
Inside, there is provided an impeller 11 having a plurality of blades 3 extending across the outer peripheral portions of the hub 1 and the shroud 2 and having a fan suction port 4 formed in the center of the shroud 2. A centrifugal fan 12 and a substantially annular heat exchanger 13 located on the blowout side of the centrifugal fan 12, and an air inlet 15 facing the fan inlet 4 in the casing 10, in the air conditioning apparatus to form an air outlet 16 for blowing out the conditioned air after passing through the heat exchanger 13 to the indoor, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, the hub-side together allowed to a predetermined amount offset in the counter-rotational direction of the impeller 11 than the position of the coupling portion 3b _1, wherein the maximum camber position of the camber line Cs of the pressure surface of the concave and pear and the shroud side blade element of the shroud side blade element of each vane 3 And it allowed positioned to the rear edge side chord length intermediate position smax.

According to a fourth aspect of the present invention, as a means for solving the above problems, as shown in the drawings,
Inside, there is provided an impeller 11 having a plurality of blades 3 extending across the outer peripheral portions of the hub 1 and the shroud 2 and having a fan suction port 4 formed in the center of the shroud 2. A centrifugal fan 12 and a substantially annular heat exchanger 13 located on the blowout side of the centrifugal fan 12, and an air inlet 15 facing the fan inlet 4 in the casing 10, in the air conditioning apparatus to form an air outlet 16 for blowing out the conditioned air after passing through the heat exchanger 13 to the indoor, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, the hub-side together allowed to a predetermined amount offset in the counter-rotational direction of the impeller 11 than the position of the coupling portion 3b _1, wherein the shape and without having at least one inflection point camber line Cs of the shroud side blade element of each vane (3) and its Feather The corners of the mouth .beta.s, has no greater than 'vane outlet angle .beta.s when connecting with' the same leading edge position and trailing edge position single arc camber line Cs with the same blade inlet angle .alpha.s.

According to the fifth aspect of the present invention, as means for solving the above problems, as shown in the drawings,
5. The air conditioner according to 3 or 4, wherein the pressure surface of the hub-side blade in each of the blades 3 is convex, and the camber line Ch of the hub-side blade has a maximum warp position Chmax closer to the trailing edge than the middle chord length position. It is located.

According to a sixth aspect of the present invention, as means for solving the above problems, as shown in the drawings,
5. The air conditioner according to 3 or 4, wherein the pressure surface of the hub-side blade in each of the blades 3 is concave, and the camber line Ch of the hub-side blade is located at a maximum warp position Chmax closer to the leading edge than the middle chord length position. I'm sorry.

In the invention of claim 7, as means for solving the above-mentioned problems, as shown in the drawings,
5. The air conditioner according to claim 3 or 4, wherein the camber line Ch of the hub-side blade element in each blade 3 has a shape having at least one inflection point, and the blade exit angle β
h for the same leading edge position and trailing edge position for the same blade entrance angle αh
Is smaller than the blade exit angle βh ′ when connected by a single arc camber line Ch ′ having

According to an eighth aspect of the present invention, as a means for solving the above problems, as shown in the drawings,
Inside, there is provided an impeller 11 having a plurality of blades 3 extending across the outer peripheral portions of the hub 1 and the shroud 2 and having a fan suction port 4 formed in the center of the shroud 2. A centrifugal fan 12 and a substantially annular heat exchanger 13 located on the blowout side of the centrifugal fan 12, and an air inlet 15 facing the fan inlet 4 in the casing 10, in the air conditioning apparatus to form an air outlet 16 for blowing out the conditioned air after passing through the heat exchanger 13 to the indoor, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, the hub-side together allowed to a predetermined amount offset in the counter-rotational direction of the impeller 11 than the position of the coupling portion 3b _1, wherein the maximum camber of the camber lines Ch pressure side a convex and without and the hub-side blade element of the hub-side blade element for each blade 3 Chord length at position Chmax It is located on the trailing edge side from the intermediate position.

According to a ninth aspect of the present invention, as a means for solving the above-mentioned problem, as shown in the drawings,
Inside, there is provided an impeller 11 having a plurality of blades 3 extending across the outer peripheral portions of the hub 1 and the shroud 2 and having a fan suction port 4 formed in the center of the shroud 2. A centrifugal fan 12 and a substantially annular heat exchanger 13 located on the blowout side of the centrifugal fan 12, and an air inlet 15 facing the fan inlet 4 in the casing 10, in the air conditioning apparatus to form an air outlet 16 for blowing out the conditioned air after passing through the heat exchanger 13 to the indoor, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, the hub-side The position of the connecting portion 3b ₁ is offset by a predetermined amount in the anti-rotation direction of the impeller 11, the pressure side of the hub-side blade in each blade 3 is concave, and the camber line Ch of the hub-side blade is at the maximum warp position. Chmax to chord length It is located closer to the leading edge than the middle position.

According to a tenth aspect of the present invention, as a means for solving the above problems, as shown in the drawings, a casing 1 is provided.
0, a plurality of blades 3, 3,... Straddling between the outer peripheral portions of the hub 1 and the shroud 2, and an impeller 11 having a fan suction port 4 formed in the center of the shroud 2. A centrifugal fan 12 provided with a substantially annular heat exchanger 13 located on the blow-out side of the centrifugal fan 12, and an air inlet 15 facing the fan inlet 4 in the casing 10; In the air conditioner having the air outlet 16 for blowing the conditioned air after passing through the heat exchanger 13 into the room, the position of the shroud-side joint 3b ₂ at the rear edge 3b of each of the blades 3 is defined by a hub. The camber line Ch of the hub-side blade element in each of the blades 3 is formed into a shape having at least one inflection point, while being offset by a predetermined amount from the position of the side coupling portion 3b ₁ in the anti-rotation direction of the impeller 11. Exit angle The h, single arc camber line C of the same leading edge position and trailing edge position of the same vane inlet angle αh
h 'is smaller than the blade exit angle βh'.

[0024]

According to the first aspect of the present invention, the following effects can be obtained by the above means.

That is, since the hub-side blade outlet angle βh and the shroud-side blade outlet angle βs at the trailing edge 3b of each blade 3 are substantially equal, the trailing edge 3b of the blade 3 is
(In other words, the wind speed distribution in the blowout direction on the blowout side of the impeller) is made uniform.

According to the second, third or fourth aspect of the present invention, the following effects can be obtained by the above means.

That is, the shroud-side blade exit angle βs at the trailing edge 3b of each blade 3 is larger than that of the conventional single-arc camber line Cs', and as a result, the shroud-side blade exit angle βs is reduced to the hub-side blade exit. The angle approaches the angle βh, and the wind speed distribution in the blowing direction on the trailing edge 3b side of the blade 3 (in other words, the blowing side of the impeller) becomes uniform.

According to the fifth, sixth or seventh aspect of the present invention, the following effects can be obtained by the above means.

That is, the shroud-side blade exit angle βs at the trailing edge 3b of each blade 3 is larger than that of the conventional single-arc camber line Cs ′, while the hub-side blade exit angle βh is smaller than the conventional single-arc camber line Cs ′. As a result, the shroud-side blade exit angle βs and the hub-side blade exit angle βh are substantially equal, and the trailing edge 3b of the blade 3 is reduced.
The wind speed distribution in the blowing direction on the side (in other words, the blowing side of the impeller) is made uniform.

According to the eighth, ninth or tenth aspect of the present invention, the following effects can be obtained by the above means.

That is, the hub-side blade exit angle βh at the trailing edge 3b of each blade 3 is smaller than that of the conventional single-arc camber line Ch ′, so that the hub-side blade exit angle βh is reduced to the shroud-side blade exit. The angle approaches the angle βs, and the wind speed distribution in the blowing direction on the trailing edge 3b side of the blade 3 (in other words, the blowing side of the impeller) becomes uniform.

[0032]

According to the first aspect of the present invention, the casing 1
0, a plurality of blades 3, 3,... Straddling between the outer peripheral portions of the hub 1 and the shroud 2, and an impeller 11 having a fan suction port 4 formed in the center of the shroud 2. A centrifugal fan 12 provided with a substantially annular heat exchanger 13 located on the blow-out side of the centrifugal fan 12, and an air inlet 15 facing the fan inlet 4 in the casing 10; In the air conditioner having the air outlet 16 for blowing the conditioned air after passing through the heat exchanger 13 into the room, the position of the shroud-side joint 3b ₂ at the rear edge 3b of each of the blades 3 is defined by a hub. together allowed to a predetermined amount offset in the counter-rotational direction of the impeller 11 than the position of the side coupling portion 3b _1, wherein substantially equal to the hub-side blade outlet angle βh and the shroud-side blade outlet angle βs at the rear edge 3b of the blade 3 Anyway, trailing edge of feather 3 Since the blowing direction wind speed distribution on the 3b side (in other words, the impeller blowing side) is made uniform, the wind speed distribution on the front side of the heat exchanger 13 can be adjusted throughout the vertical direction by rectifying the blowing flow. As a result, ventilation resistance and operating noise (i.e., fan operating noise and blowing noise) are reduced, heat exchanger efficiency is improved, and energy is saved (i.e., fan efficiency is improved and energy efficiency is improved). ) Can be achieved.

According to the second, third or fourth aspect of the present invention,
An impeller 1 having a plurality of blades 3, 3... Straddling between an outer peripheral portion of a hub 1 and a shroud 2 in a casing 10 and having a fan suction port 4 formed in a central portion of the shroud 2.
1 and a substantially annular heat exchanger 13 located on the outlet side of the centrifugal fan 12, and the casing 10 has an air inlet 15 opposed to the fan inlet 4. And an air outlet 16 for blowing the conditioned air after passing through the heat exchanger 13 into the room, the position of the shroud-side joint 3b _{2 at} the rear edge 3b of each of the blades 3 is determined. , together with allowed to a predetermined amount offset in the counter-rotational direction of the impeller 11 than the position of the hub-side coupling part 3b _1, wherein the camber line Cs of the pressure surface a convex and without and the shroud side blade element of the shroud side blade element of each vane 3 The maximum warping position Csmax is located on the leading edge side from the middle chord length position, or the pressure surface of the shroud-side blade element in each of the blades 3 is concave and the shroud-side blade element is The maximum warping position Csmax of the chamber line Cs is located on the trailing edge side from the middle chord length position, and the shroud-side blade exit angle βs is not larger than that of the conventional single-arc camber line Cs ′. 3 is formed into a shape having at least one inflection point, and the blade outlet angle βs is set to the same leading edge position and the trailing edge position as a single arc camber line Cs having the same blade entrance angle αs. ', The shroud-side blade outlet angle βs approaches the hub-side blade outlet angle βh, and the trailing edge 3b of the blade 3 (in other words, the impeller outlet side). ), The wind speed distribution in the blowing direction is made uniform, so that the wind speed distribution on the front side of the heat exchanger 13 is made as uniform as possible in the entire vertical direction by rectifying the blowing flow. There is an excellent effect that ventilation resistance and operation noise (that is, fan operation sound and blow sound) can be reduced, heat exchanger efficiency can be improved, and energy can be saved (that is, fan efficiency and energy efficiency can be improved). .

According to the invention of claim 5, 6 or 7,
The centrifugal fan impeller according to claim 2, 3 or 4, wherein the pressure side of the hub-side blade in each blade (3) is convex, and the camber line (Ch) of the hub-side blade has a maximum warping position (Chmax) at an intermediate chord length. And the shroud-side blade exit angle βs is made larger than that of the conventional single-arc camber line Cs ′, and the hub-side blade exit angle βh is changed to the conventional single-arc camber line Ch ′. Or the pressure side of the hub-side blade in each blade 3 is made concave, and the maximum warping position Chmax of the camber line Ch of the hub-side blade is positioned on the leading edge side from the middle position of the chord length. , The shroud-side blade exit angle βs,
In addition to making it larger than in the case of the conventional single-arc camber line Cs ', the hub-side blade exit angle βh is not smaller than that of the conventional single-arc camber line Ch', or the hub-side blade element in each blade 3 When the camber line Ch has a shape having at least one inflection point and its blade exit angle βh is connected by a single arc camber line Ch ′ having the same leading edge position and trailing edge position with the same blade entrance angle αh. The blade outlet angle βh ′ is smaller than the blade outlet angle βh ′, so that the shroud-side blade outlet angle βs and the hub-side blade outlet angle βh are not substantially equal,
Since the wind speed distribution in the blowing direction on the trailing edge 3b side of the blade 3 (in other words, the blowing side of the impeller) is made uniform, the wind speed distribution on the front side of the heat exchanger 13 is obtained by rectifying the blowing flow. Is made as uniform as possible in the entire vertical direction, the ventilation resistance and the operation noise (i.e., the fan operation sound and the blowing sound) are reduced, the efficiency of the heat exchanger is improved, and energy saving (i.e., the fan efficiency is Improvement and energy efficiency).

According to the eighth, ninth or tenth aspect of the present invention, the casing 10 has a plurality of blades 3, 3,... A centrifugal fan 12 provided with an impeller 11 having a fan suction port 4 formed in the center of the centrifugal fan, and a substantially annular heat exchanger 13 located on the blow-out side of the centrifugal fan 12 are disposed. 10 in which an air inlet 15 opposed to the fan inlet 4 and an air outlet 16 for blowing conditioned air after passing through the heat exchanger 13 into a room are formed. Trailing edge 3
The position of the shroud-side coupling portion 3b ₂ at b, together with allowed to a predetermined amount offset in the counter-rotational direction of the impeller 11 than the position of the hub-side coupling part 3b _1, convex positive pressure surface of the hub side blade element in the respective vane 3 And the maximum camber line Chmax of the camber line Ch of the hub-side blade element is positioned on the trailing edge side from the middle chord length position, and the hub-side blade outlet angle βh at the trailing edge portion 3b of each blade 3 is determined by the conventional unitary value. It is not smaller than the case of the arc camber line Ch ', or the pressure side of the hub-side blade element in each blade 3 is concave, and the maximum warping position Chmax of the camber line Ch of the hub-side blade element is located before the middle chord length position. Positioned on the edge side, the trailing edge 3 of each blade 3
The hub-side blade exit angle βh at b is not smaller than that of the conventional single-arc camber line Ch ′, or the hub-side blade camber line Ch at each blade 3 is not formed to have at least one inflection point. The blade outlet angle βh is made smaller than the blade outlet angle βh ′ when the same leading edge position and trailing edge position are connected by a single circular camber line Ch ′ having the same blade inlet angle αh, and the hub side blade outlet angle βh is made closer to the shroud-side blade exit angle βs, and the wind direction distribution on the trailing edge 3b side of the blade 3 (in other words, the blowout side of the impeller) is made uniform. As a result, the wind speed distribution on the front side of the heat exchanger 13 is made as uniform as possible in the entire vertical direction,
There is an excellent effect that ventilation resistance and operation noise (that is, fan operation sound and blow sound) can be reduced, heat exchanger efficiency can be improved, and energy can be saved (that is, fan efficiency and energy efficiency can be improved). .

[0036]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 18, the air conditioner described in each of the following embodiments is a so-called ceiling-mounted type air conditioner embedded in a ceiling surface 20.
It has a casing 10 fixedly arranged at zero.

The casing 10 is provided with a bottom wall member 4 provided with an air inlet 15 at the center of a lower surface 10a thereof, and an air outlet 16 which is directed obliquely downward at an outer edge 10b of the lower surface 10a. 16 .. are formed. Inside the casing 10, a motor 8 fixedly supported on the upper surface 10c thereof, and a rotating shaft 8 of the motor 8 are provided.
A centrifugal fan 12 composed of an impeller 11 described below and fixed to a is disposed in a state of being located on the axis of the air suction port 15. Reference numeral 17 denotes an electric heater.

The impeller 11 has a hub 1 fixed to the rotating shaft 8a of the motor 8 and a shroud 2 having a fan suction port 4 corresponding to the air suction port 15 formed at the center thereof at a predetermined interval. A plurality of blades 3, 3 are arranged between the outer peripheral portions of the hub 1 and the shroud 2 while being opposed to each other.
Are arranged at predetermined intervals in the circumferential direction. A substantially annular heat exchanger 13 is disposed in the casing 10 so as to cross a ventilation path 19 extending from the centrifugal fan 12 to each of the air outlets 16. In the case of the present embodiment, the diameter of the heat exchanger 13 is made smaller than that conventionally used in order to reduce the size and size of the air conditioner. Heat exchanger 1 to ensure the same exchange capacity as before
The axial height Ht of No. 3 is set higher than that conventionally used.

On the other hand, in the impeller 12 of this embodiment,
As described above, the blades 3, 3,... Of the centrifugal fan 12 correspond to the heat exchanger 13 having the higher axial height Ht.
The height Hf in the axial direction is higher than that conventionally used. Thus, the area of the outlet side opening of the centrifugal fan 12 is larger than the opening area of the fan suction port 4.

In the air conditioner configured as described above, the impeller 11 of the centrifugal fan 12 is rotated by the motor 8, so that the air A sucked from the air suction port 15 is out of the radial direction of the impeller 11. After being sent out, the air passes through the heat exchanger 13 and is blown out as conditioned air from the air outlets 16, 16,.

[0042] The position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3 has been brought predetermined amount offset in the reverse rotation direction from the position of the hub-side coupling part 3b ₁
(See FIGS. 21 and 22). With such a configuration, as described in the section of the related art, while the air flowing from the leading edge 3a of the blade 3 flows toward the trailing edge 3b of the blade 3, the air flows toward the shroud 2 side. The force is received from the blade surface, and the shroud 2 at the exit side of the blade 3
The generation of the separation flow on the side is suppressed.

Embodiment 1 FIG. 1 shows the shape of the vane camber wires on the hub side and the shroud side in the impeller of the centrifugal fan used in the air conditioner according to Embodiment 1 of the present invention.
This embodiment corresponds to the first and second aspects of the present invention.

In the case of this embodiment, the pressure surface of the shroud-side blade in the blade 3 is convex, and the maximum warping position Csmax of the camber line Cs of the shroud-side blade is located on the leading edge side from the middle chord length position. It has been impatient. In the case of the present embodiment, the shroud-side blade entrance angle αs of the blade 3 is set to the same angle as when the camber line of the shroud-side blade element is a single arc camber line Cs ′. Further, the camber line Ch of the hub-side blade element has a single arc shape. The symbol Csmax 'is a single arc camber line C
This is the maximum warpage position of s'.

With the above configuration, the following operation can be obtained.

[0046] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blades have a single arc shape, the shroud-side blade outlet angle βs ′ becomes smaller than the hub-side blade outlet angle βh, but as in the present embodiment, the camber of the shroud-side blades When the maximum warping position Csmax of the line Cs is located on the leading edge side from the middle chord length position, the shroud-side blade exit angle βs becomes βs> βs ′.

Accordingly, the shroud-side blade outlet angle βs approaches the hub-side blade outlet angle βh, and the blade 3
(In other words, the wind speed distribution in the blowout direction on the blowout side of the impeller) is made uniform, so that the blowout flow can be rectified. This means that ventilation resistance and driving noise (i.e.
It greatly contributes to reduction of fan operation sound and blow sound, improvement of heat exchanger efficiency and energy saving (that is, improvement of fan efficiency and energy efficiency).

Embodiment 2 FIG. 2 shows the shape of the blade camber wires on the hub side and the shroud side of the impeller of the centrifugal fan used in the air conditioner according to Embodiment 2 of the present invention.
This embodiment corresponds to the first and third aspects of the present invention.

In the case of this embodiment, the pressure surface of the shroud-side blade in the blade 3 is concave, and the maximum warping position Csmax of the camber line Cs of the shroud-side blade is located on the trailing edge side from the middle position of the chord length. Have been. In the case of the present embodiment, the shroud-side blade entrance angle αs of the blade 3 is set to the same angle as when the camber line of the shroud-side blade element is a single arc camber line Cs ′. Further, the camber line Ch of the hub-side blade element has a single arc shape. The symbol Csmax 'is a single arc camber line C
This is the maximum warpage position of s'.

With the above configuration, the following operation can be obtained.

[0051] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blades have a single arc shape, the shroud-side blade outlet angle βs ′ becomes smaller than the hub-side blade outlet angle βh, but as in the present embodiment, the camber of the shroud-side blades When the maximum warpage position Csmax of the line Cs is positioned on the trailing edge side from the middle chord length position, the shroud-side blade exit angle βs becomes βs> βs ′.

Therefore, the shroud-side blade outlet angle βs approaches the hub-side blade outlet angle βh, and the blade 3
(In other words, the wind speed distribution in the blowout direction on the blowout side of the impeller) is made uniform, so that the blowout flow can be rectified. This means that ventilation resistance and driving noise (i.e.
It greatly contributes to reduction of fan operation sound and blow sound, improvement of heat exchanger efficiency and energy saving (that is, improvement of fan efficiency and energy efficiency).

Third Embodiment FIG. 3 shows the shape of the blade camber lines on the hub side and the shroud side of the impeller of the centrifugal fan used in the air conditioner according to the third embodiment of the present invention.
This embodiment corresponds to the first and fourth aspects of the present invention.

[0054] In the present embodiment, together with the camber line Cs of the shroud side blade element of the blade 3 is shaped to have one inflection point P _1, the blade outlet angle βs is the same leading edge position and trailing edge position Are connected to each other by a single arc camber line Cs 'having the same blade entrance angle αs, the blade exit angle βs' is made larger. Further, the camber line Ch of the hub-side blade element has a single arc shape.

With the above configuration, the following operation can be obtained.

[0056] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blade element have a single circular arc shape, the shroud-side blade outlet angle βs ′ becomes smaller than the hub-side blade outlet angle βh, but in this embodiment, the shroud-side blade outlet angle βs Is βs> βs ′.

Therefore, the shroud-side blade outlet angle βs approaches the hub-side blade outlet angle βh, and the blade 3
(In other words, the wind speed distribution in the blowout direction on the blowout side of the impeller) is made uniform, so that the blowout flow can be rectified. This means that ventilation resistance and driving noise (i.e.
It greatly contributes to reduction of fan operation sound and blow sound, improvement of heat exchanger efficiency and energy saving (that is, improvement of fan efficiency and energy efficiency).

Fourth Embodiment FIG. 4 shows the shape of the vane camber lines on the hub side and the shroud side of the impeller of the centrifugal fan used in the air conditioner according to the fourth embodiment of the present invention.
This embodiment corresponds to the first, second and fifth aspects of the present invention.

In the case of the present embodiment, the pressure surface of the hub-side blade element in the first embodiment is made convex, and the camber line Ch of the hub-side blade element has a maximum warping position Chmax closer to the trailing edge than the middle chord length position. It is located. In the case of this embodiment, the hub-side blade entrance angle αh of the blade 3 is set to the same angle as when the camber line of the hub-side blade element is a single circular camber line Ch ′. The symbol Chmax 'is the maximum warping position of the single circular camber line Ch'. Other configurations are the same as in the first embodiment.

With the above configuration, the following operation can be obtained.

[0061] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blade element have a single arc shape, the shroud-side blade outlet angle βs ′ becomes smaller than the hub-side blade outlet angle βh ′, but in this embodiment, the shroud-side blade outlet angle βs becomes βs> βs ′, and the hub-side blade exit angle βh becomes βh <βh ′.

Accordingly, the shroud-side blade outlet angle βs and the hub-side blade outlet angle βh are substantially equal, and the blow direction wind speed distribution on the trailing edge 3b side of the blade 3 (in other words, the blowout side of the impeller) is determined. As a result, the blowout flow can be rectified. This means that ventilation resistance and driving noise
(I.e., the fan operation sound and the blowing sound), greatly contribute to the improvement of the efficiency of the heat exchanger and the energy saving (that is, the improvement of the fan efficiency and the improvement of the energy efficiency).

Fifth Embodiment FIG. 5 shows the shapes of the blade camber wires on the hub side and the shroud side in the impeller of the centrifugal fan used in the air conditioner according to the fifth embodiment of the present invention.
This embodiment corresponds to the first, second and sixth aspects of the present invention.

In the case of the present embodiment, the pressure surface of the hub-side blade in the first embodiment is concave, and the maximum warping position Chmax of the camber line Ch of the hub-side blade is located on the leading edge side from the middle chord length position. It has been impatient. In the case of this embodiment, the hub-side blade entrance angle αh of the blade 3 is set to the same angle as when the camber line of the hub-side blade element is a single circular camber line Ch ′. The symbol Chmax 'is the maximum warping position of the single circular camber line Ch'. Other configurations are the same as in the first embodiment.

With the above configuration, the following operation can be obtained.

[0066] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blade element have a single arc shape, the shroud-side blade outlet angle βs ′ becomes smaller than the hub-side blade outlet angle βh ′, but in this embodiment, the shroud-side blade outlet angle βs becomes βs> βs ′, and the hub-side blade exit angle βh becomes βh <βh ′.

Accordingly, the shroud-side blade outlet angle βs and the hub-side blade outlet angle βh are substantially equal, and the airflow direction wind speed distribution on the trailing edge 3b side of the blade 3 (in other words, the blowing side of the impeller) is determined. As a result, the blowout flow can be rectified. This means that ventilation resistance and driving noise
(I.e., the fan operation sound and the blowing sound), greatly contribute to the improvement of the efficiency of the heat exchanger and the energy saving (that is, the improvement of the fan efficiency and the improvement of the energy efficiency).

Sixth Embodiment FIG. 6 shows the shape of the blade camber wires on the hub side and the shroud side of the impeller of the centrifugal fan used in the air conditioner according to the sixth embodiment of the present invention.
This embodiment corresponds to the first, second and seventh aspects of the present invention.

[0069] In this embodiment, with camber line Ch of the hub-side blade element is a shape having a single inflection point P ₂ in the first embodiment, the blade outlet angle βh is the same leading edge position and trailing The position is smaller than the blade exit angle βh ′ when the positions are connected by a single arc camber line Ch ′ having the same blade entrance angle αh. Other configurations are the same as in the first embodiment.

With the above configuration, the following operation can be obtained.

[0071] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blade element have a single arc shape, the shroud-side blade outlet angle βs ′ becomes smaller than the hub-side blade outlet angle βh ′, but in this embodiment, the shroud-side blade outlet angle βs becomes βs> βs ′, and the hub-side blade exit angle βh becomes βh <βh ′.

Accordingly, the shroud-side blade outlet angle βs and the hub-side blade outlet angle βh become substantially equal, and the wind direction distribution on the trailing edge 3b side of the blade 3 (in other words, the blowout side of the impeller) is determined. As a result, the blowout flow can be rectified. This means that ventilation resistance and driving noise
(I.e., the fan operation sound and the blowing sound), greatly contribute to the improvement of the efficiency of the heat exchanger and the energy saving (that is, the improvement of the fan efficiency and the improvement of the energy efficiency).

Seventh Embodiment FIG. 7 shows the shapes of the blade camber lines on the hub side and the shroud side in the impeller of the centrifugal fan used in the air conditioner according to the seventh embodiment of the present invention.
This embodiment corresponds to the first, third and fifth aspects of the present invention.

In the case of the present embodiment, the pressure surface of the hub-side blade element in the second embodiment is convex, and the maximum camber line Chmax of the hub-side blade element is located closer to the trailing edge than the middle chord length position. It is located. In the case of this embodiment, the hub-side blade entrance angle αh of the blade 3 is set to the same angle as when the camber line of the hub-side blade element is a single circular camber line Ch ′. The symbol Chmax 'is the maximum warping position of the single circular camber line Ch'. Other configurations are the same as those of the second embodiment.

With the above configuration, the following operation can be obtained.

[0076] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blade element have a single arc shape, the shroud-side blade outlet angle βs ′ becomes smaller than the hub-side blade outlet angle βh ′, but in this embodiment, the shroud-side blade outlet angle βs becomes βs> βs ′, and the hub-side blade exit angle βh becomes βh <βh ′.

Accordingly, the shroud-side blade outlet angle βs and the hub-side blade outlet angle βh are substantially equal, and the blowing direction wind speed distribution on the trailing edge 3b side of the blade 3 (in other words, on the blade side of the impeller) is determined. As a result, the blowout flow can be rectified. This means that ventilation resistance and driving noise
(I.e., the fan operation sound and the blowing sound), greatly contribute to the improvement of the efficiency of the heat exchanger and the energy saving (that is, the improvement of the fan efficiency and the improvement of the energy efficiency).

Eighth Embodiment FIG. 8 shows the shapes of the blade camber lines on the hub side and the shroud side in the impeller of the centrifugal fan used in the air conditioner according to the eighth embodiment of the present invention.
This embodiment corresponds to the first, third and sixth aspects of the present invention.

In the case of the present embodiment, the pressure side of the hub-side blade in the second embodiment is concave, and the maximum warping position Chmax of the camber line Ch of the hub-side blade is located closer to the leading edge than the middle chord length position. It has been impatient. In the case of this embodiment, the hub-side blade entrance angle αh of the blade 3 is set to the same angle as when the camber line of the hub-side blade element is a single circular camber line Ch ′. The symbol Chmax 'is the maximum warping position of the single circular camber line Ch'. Other configurations are the same as those of the second embodiment.

With the above configuration, the following operation can be obtained.

[0081] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blade element have a single arc shape, the shroud-side blade outlet angle βs ′ becomes smaller than the hub-side blade outlet angle βh ′, but in this embodiment, the shroud-side blade outlet angle βs becomes βs> βs ′, and the hub-side blade exit angle βh becomes βh <βh ′.

Accordingly, the shroud-side blade outlet angle βs and the hub-side blade outlet angle βh are substantially equal, and the airflow distribution in the blowing direction on the trailing edge 3b side of the blade 3 (in other words, the blowing side of the impeller) is determined. As a result, the blowout flow can be rectified. This means that ventilation resistance and driving noise
(I.e., the fan operation sound and the blowing sound), greatly contribute to the improvement of the efficiency of the heat exchanger and the energy saving (that is, the improvement of the fan efficiency and the improvement of the energy efficiency).

Ninth Embodiment FIG. 9 shows the shapes of the blade camber lines on the hub side and the shroud side of the impeller of the centrifugal fan used in the air conditioner according to the ninth embodiment of the present invention.
This embodiment corresponds to the first, third and seventh aspects of the present invention.

[0084] In this embodiment, with camber line Ch of the hub-side blade element is a shape having a single inflection point P ₂ in the second embodiment, the blade outlet angle βh is the same leading edge position and trailing The position is smaller than the blade exit angle βh ′ when the positions are connected by a single arc camber line Ch ′ having the same blade entrance angle αh. Other configurations are the same as those of the second embodiment.

With the above configuration, the following operation can be obtained.

[0086] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blade element have a single arc shape, the shroud-side blade outlet angle βs ′ becomes smaller than the hub-side blade outlet angle βh ′, but in this embodiment, the shroud-side blade outlet angle βs becomes βs> βs ′, and the hub-side blade exit angle βh becomes βh <βh ′.

Accordingly, the shroud-side blade outlet angle βs and the hub-side blade outlet angle βh are substantially equal, and the wind direction distribution on the trailing edge 3b side of the blade 3 (in other words, on the blade side of the impeller) is determined. As a result, the blowout flow can be rectified. This means that ventilation resistance and driving noise
(I.e., the fan operation sound and the blowing sound), greatly contribute to the improvement of the efficiency of the heat exchanger and the energy saving (that is, the improvement of the fan efficiency and the improvement of the energy efficiency).

Tenth Embodiment FIG. 10 shows the shape of the blade camber wires on the hub side and the shroud side of the impeller of the centrifugal fan used in the air conditioner according to the tenth embodiment of the present invention. This embodiment corresponds to the first, fourth and fifth aspects of the present invention.

In the case of the present embodiment, the pressure side of the hub-side blade in the third embodiment is convex, and the maximum warping position Chmax of the camber line Ch of the hub-side blade is closer to the trailing edge than the middle chord length position. It is located. In the case of this embodiment, the hub-side blade entrance angle αh of the blade 3 is set to the same angle as when the camber line of the hub-side blade element is a single circular camber line Ch ′. The symbol Chmax 'is the maximum warping position of the single circular camber line Ch'. Other configurations are the same as those of the third embodiment.

With the above configuration, the following operation can be obtained.

[0091] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blade element have a single arc shape, the shroud-side blade outlet angle βs ′ becomes smaller than the hub-side blade outlet angle βh ′, but in this embodiment, the shroud-side blade outlet angle βs becomes βs> βs ′, and the hub-side blade exit angle βh becomes βh <βh ′.

Accordingly, the shroud-side blade outlet angle βs and the hub-side blade outlet angle βh become substantially equal, and the airflow direction wind speed distribution on the trailing edge 3b side of the blade 3 (in other words, on the blade side of the impeller) is determined. As a result, the blowout flow can be rectified. This means that ventilation resistance and driving noise
(I.e., the fan operation sound and the blowing sound), greatly contribute to the improvement of the efficiency of the heat exchanger and the energy saving (that is, the improvement of the fan efficiency and the improvement of the energy efficiency).

Eleventh Embodiment FIG. 11 shows the shape of the blade camber lines on the hub side and the shroud side of the impeller of the centrifugal fan used in the air conditioner according to the eleventh embodiment of the present invention. This embodiment corresponds to the first, fourth and sixth aspects of the present invention.

In the case of the present embodiment, the pressure side of the hub-side blade element in the third embodiment is concave, and the camber line Ch of the hub-side blade element has a maximum warp position Chmax located on the leading edge side from the middle chord length position. It has been impatient. In the case of this embodiment, the hub-side blade entrance angle αh of the blade 3 is set to the same angle as when the camber line of the hub-side blade element is a single circular camber line Ch ′. The symbol Chmax 'is the maximum warping position of the single circular camber line Ch'. Other configurations are the same as those of the third embodiment.

With the above configuration, the following operation can be obtained.

[0096] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blade element have a single arc shape, the shroud-side blade outlet angle βs ′ becomes smaller than the hub-side blade outlet angle βh ′, but in this embodiment, the shroud-side blade outlet angle βs becomes βs> βs ′, and the hub-side blade exit angle βh becomes βh <βh ′.

Accordingly, the shroud-side blade outlet angle βs and the hub-side blade outlet angle βh become substantially equal, and the wind direction distribution on the trailing edge 3b side of the blade 3 (in other words, the blowout side of the impeller) is determined. As a result, the blowout flow can be rectified. This means that ventilation resistance and driving noise
(I.e., the fan operation sound and the blowing sound), greatly contribute to the improvement of the efficiency of the heat exchanger and the energy saving (that is, the improvement of the fan efficiency and the improvement of the energy efficiency).

Embodiment 12 FIG. 12 shows the shape of the blade camber wires on the hub side and the shroud side of the impeller of the centrifugal fan used in the air conditioner according to Embodiment 12 of the present invention. This embodiment corresponds to the first, fourth and seventh aspects of the present invention.

[0099] In this embodiment, with camber line Ch of the hub-side blade element is a shape having a single inflection point P ₂ in the third embodiment, the blade outlet angle βh is the same leading edge position and trailing The position is smaller than the blade exit angle βh ′ when the positions are connected by a single arc camber line Ch ′ having the same blade entrance angle αh. Other configurations are the same as those of the third embodiment.

With the above configuration, the following operation can be obtained.

[0102] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blade element have a single arc shape, the shroud-side blade outlet angle βs ′ becomes smaller than the hub-side blade outlet angle βh ′, but in this embodiment, the shroud-side blade outlet angle βs becomes βs> βs ′, and the hub-side blade exit angle βh becomes βh <βh ′.

Accordingly, the shroud-side blade outlet angle βs and the hub-side blade outlet angle βh are substantially equal, and the blowing direction wind speed distribution on the trailing edge 3b side of the blade 3 (in other words, the blowing side of the impeller) is determined. As a result, the blowout flow can be rectified. This means that ventilation resistance and driving noise
(I.e., the fan operation sound and the blowing sound), greatly contribute to the improvement of the efficiency of the heat exchanger and the energy saving (that is, the improvement of the fan efficiency and the improvement of the energy efficiency).

Embodiment 13 FIG. 13 shows the shape of the blade camber wires on the hub side and the shroud side of the impeller of the centrifugal fan used in the air conditioner according to Embodiment 13 of the present invention. This embodiment corresponds to the first and eighth aspects of the present invention.

In the case of the present embodiment, the pressure surface of the hub-side blade element in the blade 3 is convex, and the camber line Ch of the hub-side blade element has a maximum warp position Chmax located closer to the trailing edge than the middle chord length position. It has been impatient. In the case of this embodiment, the hub-side blade entrance angle αh of the blade 3 is set to the same angle as when the camber line of the hub-side blade element is a single circular camber line Ch ′. In addition, the camber line Cs of the shroud-side blade element has a single arc shape. The symbol Chmax 'is the maximum warping position of the single circular camber line Ch'.

With the above configuration, the following operation can be obtained.

[0106] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blade element have a single arc shape, the shroud-side blade outlet angle βs becomes smaller than the hub-side blade outlet angle βh ′. When the maximum warping position Chmax of the line Ch is located on the trailing edge side from the middle chord length position, the hub side blade exit angle βh
Becomes βh <βh ′.

Therefore, the shroud-side blade outlet angle βh approaches the hub-side blade outlet angle βs, and the blade 3
(In other words, the wind speed distribution in the blowout direction on the blowout side of the impeller) is made uniform, so that the blowout flow can be rectified. This means that ventilation resistance and driving noise (i.e.
It greatly contributes to reduction of fan operation sound and blow sound, improvement of heat exchanger efficiency and energy saving (that is, improvement of fan efficiency and energy efficiency).

Embodiment 14 FIG. 14 shows the shape of the blade camber wires on the hub side and the shroud side of the impeller of the centrifugal fan used in the air conditioner according to Embodiment 14 of the present invention. This embodiment corresponds to the first and ninth aspects of the present invention.

In the case of this embodiment, the pressure side of the hub-side blade in the blade 3 is concave, and the maximum camber line Chmax of the hub-side blade is located closer to the leading edge than the middle chord length. Have been. In the case of the present embodiment, the hub-side blade entrance angle αh of the blade 3 is the same angle as when the camber line of the hub-side blade element is a single-arc camber line Ch ′. In addition, the camber line Cs of the shroud-side blade element has a single arc shape. The symbol Chmax 'is the maximum warping position of the single circular camber line Ch'.

With the above configuration, the following operation can be obtained.

[0111] Normally, the position of the shroud-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element If both the Ch and the camber line Cs of the shroud-side blade element have a single arc shape, the shroud-side blade outlet angle βs becomes smaller than the hub-side blade outlet angle βh ′. When the maximum warping position Chmax of the line Ch is positioned on the leading edge side from the middle chord length position, the hub-side blade exit angle βh
Becomes βh <βh ′.

Accordingly, the shroud-side blade outlet angle βh approaches the hub-side blade outlet angle βs, and the blade 3
(In other words, the wind speed distribution in the blowout direction on the blowout side of the impeller) is made uniform, so that the blowout flow can be rectified. This means that ventilation resistance and driving noise (i.e.
It greatly contributes to reduction of fan operation sound and blow sound, improvement of heat exchanger efficiency and energy saving (that is, improvement of fan efficiency and energy efficiency).

Embodiment 15 FIG. 15 shows the shape of the blade camber lines on the hub side and the shroud side in the impeller of the centrifugal fan used in the air conditioner according to Embodiment 3 of the present invention. This embodiment corresponds to the first and tenth aspects of the present invention.

[0114] In this embodiment, with camber line Ch of the hub-side blade element is a shape having a single inflection point P ₂ in the blade 3, the blade outlet angle βh is the same leading edge position and trailing edge position Are connected to each other by a single circular camber line Ch ′ having the same blade entrance angle αh. The camber line Cs of the shroud-side blade element has a single arc shape.

With the above configuration, the following operation can be obtained.

[0116] Normally, the position of the hub-side coupling portion 3b ₂ of the trailing edge 3b of the blade 3, when allowed a predetermined amount offset in the anti-rotation direction from the position of the hub-side coupling part 3b _1, camber line of the hub-side blade element When both the Ch and the camber line Cs of the shroud-side blade element have a single arc shape, the shroud-side blade outlet angle βs becomes smaller than the hub-side blade outlet angle βh ′, but in the present embodiment, the hub-side blade outlet angle βh Is βh <
βh ′.

Therefore, the hub-side blade exit angle βh approaches the shroud-side blade exit angle βs, and the trailing edge 3b of the blade 3
(In other words, the wind speed distribution in the blowout direction on the blowout side of the impeller) is made uniform, so that the blowout flow can be rectified. This means that ventilation resistance and driving noise (i.e.
It greatly contributes to reduction of fan operation sound and blow sound, improvement of heat exchanger efficiency and energy saving (that is, improvement of fan efficiency and energy efficiency).

Incidentally, taking the sixth embodiment as an example as a representative of each of the above embodiments, the air volume Q (m ³ / mi
When the changes in the static pressure Ps (mmAq) and the running noise S (dBA) with respect to n) were tested, the results shown in FIGS. 17 and 16 were obtained. Here, ● shows the case of the conventional example, and ○ shows the case of the sixth embodiment.

According to this, it is understood that the driving sound S is reduced and the static pressure Ps is improved in the sixth embodiment as compared with the conventional example. Note that such a tendency can be assumed to be the same in other embodiments for the reason described in each of the above embodiments.

In each of the above embodiments, the blade 3 has a wing shape. However, it goes without saying that the blade 3 may have a plate shape.

In each of the above embodiments, an air conditioner using a turbo centrifugal fan has been described. However, the present invention is also applicable to an air conditioner using a mixed flow fan.

The present invention is not limited to the configuration of each of the above embodiments, and it is needless to say 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 diagram showing the shape of a blade camber wire on a hub side and a shroud side in an impeller of a centrifugal fan used in an air conditioner according to Embodiment 1 of the present invention.

FIG. 2 is a diagram showing the shape of a blade camber wire on a hub side and a shroud side in an impeller of a centrifugal fan used in an air conditioner according to Embodiment 2 of the present invention.

FIG. 3 is a diagram showing the shape of a blade element camber line on a hub side and a shroud side in an impeller of a centrifugal fan used in an air conditioner according to Embodiment 3 of the present invention.

FIG. 4 is a diagram illustrating the shape of a blade element camber wire on a hub side and a shroud side in an impeller of a centrifugal fan used in an air conditioner according to Embodiment 4 of the present invention.

FIG. 5 is a diagram showing the shape of a blade element camber wire on a hub side and a shroud side in an impeller of a centrifugal fan used in an air conditioner according to Embodiment 5 of the present invention.

FIG. 6 is a diagram showing the shape of blade element camber lines on a hub side and a shroud side in an impeller of a centrifugal fan used in an air conditioner according to Embodiment 6 of the present invention.

FIG. 7 is a diagram showing the shape of a blade camber wire on a hub side and a shroud side in an impeller of a centrifugal fan used in an air conditioner according to a seventh embodiment of the present invention.

FIG. 8 is a diagram showing the shape of a blade camber wire on a hub side and a shroud side in an impeller of a centrifugal fan used in an air conditioner according to Embodiment 8 of the present invention.

FIG. 9 is a diagram showing the shape of a blade camber wire on a hub side and a shroud side in an impeller of a centrifugal fan used in an air conditioner according to Embodiment 9 of the present invention.

FIG. 10 is a diagram showing the shape of the blade camber wires on the hub side and the shroud side in the impeller of the centrifugal fan used in the air-conditioning apparatus according to Embodiment 10 of the present invention.

FIG. 11 is a diagram showing a shape of a blade camber wire on a hub side and a shroud side of an impeller of a centrifugal fan used in an air conditioner according to Embodiment 11 of the present invention.

FIG. 12 is a diagram showing the shape of the blade camber wires on the hub side and the shroud side of the impeller of the centrifugal fan used in the air conditioner according to Embodiment 12 of the present invention.

FIG. 13 is a diagram showing the shape of blade element camber lines on the hub side and the shroud side of the impeller of a centrifugal fan used in the air conditioner according to Embodiment 13 of the present invention.

FIG. 14 is a diagram showing the shape of the blade camber wires on the hub side and the shroud side of the impeller of the centrifugal fan used in the air conditioner according to Embodiment 14 of the present invention.

FIG. 15 is a diagram showing the shape of the blade element camber lines on the hub side and the shroud side in the impeller of the centrifugal fan used in the air conditioner according to Embodiment 15 of the present invention.

FIG. 16 is an air volume-operating sound characteristic diagram for comparing Example 6 of the present invention with a conventional example.

FIG. 17 is an air volume-static pressure characteristic diagram for comparing Example 6 of the present invention with a conventional example.

FIG. 18 is a longitudinal sectional view of the air conditioner according to the embodiment of the present invention.

FIG. 19 is a perspective view showing an impeller of a general turbo centrifugal fan.

20 is a partial front view of the impeller shown in FIG.

FIG. 21 is a partial bottom view of an impeller of a conventional centrifugal fan.

FIG. 22 is a partial front view of an impeller of a conventional centrifugal fan.

[Explanation of symbols]

1 is a hub, 2 is a shroud, 3 is a blade, 3a is a blade leading edge, 3b is a blade trailing edge, 3b ₁ is a hub side connecting portion, 3b ₂ is a shroud side connecting portion, 4 is a fan suction port, and 10 is a fan inlet. Casing, 11 is an impeller, 12 is a centrifugal fan, 13 is a heat exchanger, 15 is an air inlet, 16 is an air outlet, αh is a hub-side blade inlet angle, αs is a shroud-side blade inlet angle, βh is a hub side Blade exit angle, βs is shroud-side blade exit angle, Ch is hub-side camber line, Chmax is maximum warpage position, Ch 'is hub-side single arc camber line, Cs is shroud-side camber line, Csmax is maximum warp position, Cs' Is a single arc camber line on the shroud side.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-39828 (JP, A) JP-A-62-194128 (JP, A) JP-A-1-199999 (JP, A) JP-A-60-194 156997 (JP, A) JP-A-2-70997 (JP, A) JP-A-5-39930 (JP, A)

Claims (10)

(57) [Claims] 1. A plurality of blades (3), (3) straddling between a hub (1) and an outer peripheral portion of a shroud (2) in a casing (10).
..A centrifugal fan having an impeller (11) having a fan suction port (4) in the center of the shroud (2)
(12) and a substantially annular heat exchanger (13) located on the blowout side of the centrifugal fan (12), and the casing (10) faces the fan suction port (4). An air conditioner comprising: an air inlet (15); and an air outlet (16) for blowing conditioned air after passing through the heat exchanger (13) into a room, wherein each of the blades (3) has shroud-side coupling portion at the trailing edge (3b) of the position of (3b _2), together with allowed to a predetermined amount offset in the counter-rotational direction of the hub-side coupling part impeller than the position of (3b ₁₎ (11), wherein each blade (3) An air conditioner wherein the hub-side blade exit angle (βh) and the shroud-side blade exit angle (βs) at the trailing edge (3b) are substantially equal. 2. A plurality of blades (3), (3) straddling between a hub (1) and an outer peripheral portion of a shroud (2) in a casing (10).
..A centrifugal fan having an impeller (11) having a fan suction port (4) in the center of the shroud (2)
(12) and a substantially annular heat exchanger (13) located on the blowout side of the centrifugal fan (12), and the casing (10) faces the fan suction port (4). An air conditioner comprising: an air inlet (15); and an air outlet (16) for blowing conditioned air after passing through the heat exchanger (13) into a room, wherein each of the blades (3) has shroud-side coupling portion at the trailing edge (3b) of the position of (3b _2), together with allowed to a predetermined amount offset in the counter-rotational direction of the hub-side coupling part impeller than the position of (3b ₁₎ (11), wherein each blade In (3), the pressure surface of the shroud-side blade element is made convex, and the camber line (Cs) of the shroud-side blade element has the maximum warpage (Csma).
An air conditioner wherein x) is positioned on the leading edge side from the middle chord length position. 3. A plurality of blades (3), (3) straddling between a hub (1) and an outer peripheral portion of a shroud (2) in a casing (10).
..A centrifugal fan having an impeller (11) having a fan suction port (4) in the center of the shroud (2)
(12) and a substantially annular heat exchanger (13) located on the blowout side of the centrifugal fan (12), and the casing (10) faces the fan suction port (4). An air conditioner comprising: an air inlet (15); and an air outlet (16) for blowing conditioned air after passing through the heat exchanger (13) into a room, wherein each of the blades (3) has shroud-side coupling portion at the trailing edge (3b) of the position of (3b _2), together with allowed to a predetermined amount offset in the counter-rotational direction of the hub-side coupling part impeller than the position of (3b ₁₎ (11), wherein each blade In (3), the pressure surface of the shroud-side blade element is concave and the camber line (Cs) of the shroud-side blade element has the maximum warpage (Csma).
An air conditioner wherein x) is located on the trailing edge side from the middle chord length position. 4. A plurality of blades (3), (3) spanning between a hub (1) and an outer peripheral portion of a shroud (2) in a casing (10).
..A centrifugal fan having an impeller (11) having a fan suction port (4) in the center of the shroud (2)
(12) and a substantially annular heat exchanger (13) located on the blowout side of the centrifugal fan (12), and the casing (10) faces the fan suction port (4). An air conditioner comprising: an air inlet (15); and an air outlet (16) for blowing conditioned air after passing through the heat exchanger (13) into a room, wherein each of the blades (3) has shroud-side coupling portion at the trailing edge (3b) of the position of (3b _2), together with allowed to a predetermined amount offset in the counter-rotational direction of the hub-side coupling part impeller than the position of (3b ₁₎ (11), wherein each blade The camber line (Cs) of the shroud-side blade element in (3) has a shape having at least one inflection point, and the blade exit angle thereof
(βs) is larger than the blade exit angle (βs ′) when the same leading edge position and trailing edge position are connected by a single arc camber line (Cs ′) having the same blade entrance angle (αs). And air conditioners. 5. The pressure side of the hub-side blade element in each of the blades (3) is convex, and the camber line (Ch) of the hub-side blade element has a maximum warp position (Chmax) after the chord length intermediate position. The said claim | item 2 located on the edge side,
5. The air conditioner according to 3 or 4. 6. The pressure surface of the hub-side blade element in each of the blades (3) is concave, and the camber line (Ch) of the hub-side blade element has a maximum warp position (Chmax) on the leading edge side of the chord length intermediate position. The said claim 2 characterized by the above-mentioned,
5. The air conditioner according to 3 or 4. 7. The camber line (Ch) of the hub-side blade element in each blade (3) has a shape having at least one inflection point, and the blade outlet angle (βh) is set to the same front edge position and rear edge. When the edge positions are connected by a single arc camber line (Ch ′) having the same blade entrance angle (αh), the blade exit angle (β
h ′);
5. The air conditioner according to 3 or 4. 8. A plurality of blades (3), (3) straddling between a hub (1) and an outer peripheral portion of a shroud (2) in a casing (10).
..A centrifugal fan having an impeller (11) having a fan suction port (4) in the center of the shroud (2)
(12) and a substantially annular heat exchanger (13) located on the blowout side of the centrifugal fan (12), and the casing (10) faces the fan suction port (4). An air conditioner comprising: an air inlet (15); and an air outlet (16) for blowing conditioned air after passing through the heat exchanger (13) into a room, wherein each of the blades (3) has shroud-side coupling portion at the trailing edge (3b) of the position of (3b _2), together with allowed to a predetermined amount offset in the counter-rotational direction of the hub-side coupling part impeller than the position of (3b ₁₎ (11), wherein each blade (3) The pressure side of the hub-side blade element in (3) is made convex, and the maximum warpage position (Chmax) of the camber line (Ch) of the hub-side blade element is located on the trailing edge side from the middle chord length position. Air conditioner. 9. A plurality of blades (3), (3) spanning between a hub (1) and an outer peripheral portion of a shroud (2) in a casing (10).
..A centrifugal fan having an impeller (11) having a fan suction port (4) in the center of the shroud (2)
(12) and a substantially annular heat exchanger (13) located on the blowout side of the centrifugal fan (12), and the casing (10) faces the fan suction port (4). An air conditioner comprising: an air inlet (15); and an air outlet (16) for blowing conditioned air after passing through the heat exchanger (13) into a room, wherein each of the blades (3) has shroud-side coupling portion at the trailing edge (3b) of the position of (3b _2), together with allowed to a predetermined amount offset in the counter-rotational direction of the hub-side coupling part impeller than the position of (3b ₁₎ (11), wherein each blade (3) The pressure side of the hub-side blade element in (3) is concave, and the maximum warpage position (Chmax) of the camber line (Ch) of the hub-side blade element is located on the leading edge side from the middle chord length position. Centrifugal fan impeller. 10. A plurality of blades (3) spanning between a hub (1) and an outer peripheral portion of a shroud (2) in a casing (10).
A centrifugal fan (12) having an impeller (11) having a fan suction port (4) in the center of the shroud (2); and the centrifugal fan (12). A substantially annular heat exchanger (13) located on the blow-out side of the air outlet is provided, and the casing (10) is provided with an air suction port (15) facing the fan suction port (4). An air outlet (16) for blowing the conditioned air after passing through the vessel (13) into the room, wherein the rear edge (3) of each of the blades (3) is provided.
The position of the shroud-side joint (3b ₂ ) in (b) is offset by a predetermined amount in the counter-rotating direction of the impeller (11) from the position of the hub-side joint (3b ₁ ), and the position of each of the blades (3) The camber line (Ch) of the hub-side blade element has a shape having at least one inflection point and its blade exit angle (β
h) with the same leading and trailing edge positions at the same blade entrance angle
An air conditioner characterized by being smaller than a blade exit angle (βh ′) when connected by a single arc camber line (Ch ′) having (αh).