ES2622007T3 - Air conditioner - Google Patents

Abstract

Air conditioner comprising: a tangential fan (10); and a stabilizer (32) and a rear guide (20) that are provided on respective sides of an outer periphery of the tangential fan (10) to form an air duct, having at least one of the stabilizer (32) and the rear guide ( 20), in a front end portion, level difference portions (28a-28c) that align in an axial direction of the fan and include first level difference portions (28a-28c) each of which decreases in height towards a central portion (M) in the axial direction of the fan (10); a protruding portion (27) being formed in the vicinity of at least one of the first portions with difference in level (28a, 28b) on a surface of the at least one of the stabilizer (32) and the rear guide (20), which surface it is opposite to the tangential fan (10), characterized in that: the protruding portion (27) has a protruding shape compared to its surroundings and protrudes out of the fan.

Description

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DESCRIPTION

Air conditioner Technical field

The present invention relates to an air conditioner that includes a tangential fan.

Background

A tangential fan is a blower that extends in the axial direction and includes a plurality of blades aligned in the direction of rotation. In an air conditioner that includes this tangential fan, a front tongue portion (stabilizer) and a rear tongue portion (rear guide) are provided to oppose the outer periphery of the fan, respectively. These tongue portions form an air passage on the blow side of the fan. Each tongue portion is closest to the fan at and around the front end. Between the front end portion of each tongue portion and the fan, a vortex air flow is generated. When a fan blade passes this vortex air flow, wind noise (NZ noise) is generated as a result of interference between the vortex air flow and the blade.

To suppress this wind noise, for example, JP H02 203129 A teaches that portions with level difference are provided at the front end of the front tongue portion (stabilizer) to vary the height of the front end along the length of the axial direction. The front tongue portion is closest to the fan at the front end. Each portion with difference in level extends in an orthogonal direction to the axial direction, and the leading end of a portion between adjacent portions with difference in level deviates from the axial direction of the fan in the direction of rotation. With this arrangement, because the blade does not pass the front end of the front tongue portion at once, wind noise is generated and wind noise is suppressed continuously.

Summary of the invention

[Technical problem]

In the air conditioner of JP H02 203129 A, because level differences are formed at the front end of the front tongue portion, a vortex air flow is curved around each portion with level difference and, Therefore, it is unstable.

The wind speed distribution of the tangential fan is arranged on the blow side so that the wind speed increases towards the center in the axial direction of the fan, and therefore the flow of the air sucked into the fan tends to converge in the center in the axial direction of the fan. For this reason, as shown in FIG. 21, about a portion with level difference 91a that decreases in height towards the center in the axial direction of the fan 90 of the portions with level difference of the front tongue portion 91, the air flow changes its direction towards that portion with difference of level 91a and rises above the portion with difference of level 91a. As a result, the air flows in a curved portion of the vortex air flow in a concentrated manner, with the result that the vortex air flow is disturbed and the wind noise increases.

The same problem also occurs when level differences are provided at the front end of the rear tongue portion.

Additionally, JP H11 304178 A discloses a transverse fan air blower that includes a transverse fan that is composed of a large number of unit fans arranged in a row, a motor that transmits a driving force of the transverse fan, a rear guide which provides a passage of air extracted by the transverse fan, and a stabilizer that is placed in front of the transverse fan and is provided with a semi-circular oriented portion that defines an appropriate separation distance with the outer peripheral surface of the transverse fan and stabilizes a vortex generated at the time of rotating the cross fan. A rib is formed in the oriented portion of the stabilizer and such a rib changes the upper part thereof so that the position of the upper part is continuously and regularly changed along an axial direction of the transverse fan at the time of rotate the transverse fan while always maintaining the appropriate separation distance with the outer peripheral surface of the transverse fan, thereby dispersing the time point of noise generation.

JP H01 167494 A discloses a tangential fan that includes a shoulder portion provided near a peripheral side face of a fan body and an inner wall of a cover that forms an air discharge opening. A protruding part is provided in an inner corner portion of the shoulder portion for the purpose of making a small separation distance between the fan body and the shoulder portion. A vortex vane fixing position is provided, which grinds the vortex that goes to the discharge opening and that recovers even more static pressure in the projection part towards the tangential direction at the lower end of the fan body.

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An objective of the present invention is to provide an air conditioner in which wind noise is suppressed by restricting the disturbance of a vortex air flow.

[Solution to the problem]

An air conditioner in accordance with the present invention is defined by the combination of features of claim 1. The dependent claims refer to preferred embodiments.

According to the first aspect of the invention, an air conditioner includes: a tangential fan; and a stabilizer and a rear guide which are provided on respective sides of an outer periphery of the tangential fan to form an air passage, having at least one of the stabilizer and the rear guide, at a front end portion, portions with level difference which are aligned in an axial direction and include first portions with level difference each of which decreases in height towards a central part in the axial direction of the fan; an outstanding portion being formed in the vicinity of at least one of the first portions with difference in level on a surface of the at least one of the stabilizer and the rear guide, surface that is opposite to the tangential fan.

In this air conditioner, at least one of the stabilizer and the rear guider has an outstanding portion that has an outstanding shape compared to its vicinity and protrudes outward from the fan, in the vicinity of the first portion with level difference that decreases by height towards the central part of the fan. For this reason, it is unlikely that the flow of air sucked into the fan will rise above the protruding portion. As such, the air fluid is restricted in a concentrated manner in the curved portion of the vortex air flow generated between each of the first portions with level difference and the fan, and therefore the flow disturbance is restricted of vortex air. As a result, wind noise is suppressed. Also, because the portions with difference in level are provided in the front end portion of at least one of the stabilizer and the rear guide, it is possible to make the fan blade pass the end portions in the axial direction of the portion with difference in level at different times or make the blade not pass the part between the portions with difference in level once since the height of this part between the portions with level difference gradually changes in the axial direction. As such, wind noise is suppressed by differentiating the wind noise generation moments in this way.

According to the second aspect of the invention, the air conditioner of the first aspect is arranged so that the protruding portion is formed along the first portion with difference in level.

In this air conditioner, because the protruding portion is formed along the first portion with level difference, it is possible to restrict the flow of air sucked into the fan that rises above the first portions with level difference . With this, it is possible to effectively further restrict the air flow in the curved portion of the vortex air flow in a concentrated manner.

According to the third aspect of the invention, the air conditioner of the first or second aspect is arranged so that the projecting portion is provided in the vicinity of a first portion with difference in level which is the furthest in the axial direction of the central part of the fan, of the first portions with level difference.

In this air conditioner, because the air flow sucked into the tangential fan tends to converge in the central part of the fan in the axial direction, the disturbance of the vortex air flow is additionally suppressed effectively when provided the protruding portion in the vicinity of the first portion with difference in level is the furthest from the central part of the fan in the axial direction.

According to the fourth aspect of the invention, the air conditioner of any one of the first to third aspects is arranged so that at least one of the stabilizer and the rear guide also includes one or more protruding portions, and the two or more protruding portions are arranged so that, the farther a protruding portion of the central part of the fan is in the axial direction, the higher the protruding height of the protruding portion will be.

In this air conditioner, because the flow of air sucked into the tangential fan tends to converge in the central part of the fan in the axial direction, the disturbance of the vortex air flow is suppressed additionally when the more far away is an overhanging portion of the central part of the fan in the axial direction, the higher the overhanging height of the overhanging portion will be.

According to the fifth aspect of the invention, the air conditioner of any one of the first to fourth aspects is arranged so that each of the first portions with level difference extends linearly or curved from the point highest to the lowest point.

In this air conditioner, the first portions with difference in level are easily formed because the first portions with difference in level extend linearly or in a curved manner through the whole in the axial direction.

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According to the sixth aspect of the invention, the air conditioner of any one of the first to fourth aspects is arranged so that the height of each of the first portions with level difference changes in sections.

In this air conditioner, because each first portion with difference in level changes in height in sections, the inclination of the first portion with difference in level is adjustable regardless of the length in the axial direction of the first portion with difference of level.

In accordance with the seventh aspect of the invention, the air conditioner of any one of the first to sixth aspects is arranged so that two first portions are provided with level difference of the first portions with level difference to collide with each other, and the height of a part between the two adjacent level difference portions gradually changes in the axial direction.

In this air conditioner, because the height of the part between the adjoining of the portions with difference of level gradually changes in the axial direction, the blade does not pass through this part between the adjoining parts of the portions with difference level once. For this reason, when the blade passes through the part between the portions with difference in level, wind noise is generated, and therefore wind noise is suppressed continuously.

According to the eighth aspect of the invention, the air conditioner of any one of the first to sixth aspects is arranged so that a portion with level difference that increases in height is provided towards the central part of the fan in the direction axial in the vicinity of one of the first portions with level difference, and the height of one part between the two portions with adjacent level difference is constant in the axial direction.

In this air conditioner, because in at least one of the stabilizer and the rear guide the height of the part between the portions with difference in level is constant in the axial direction, the stabilizer or the rear guide can be easily formed.

According to the ninth aspect of the invention, the air conditioner of any one of the first to eighth aspects is arranged so that the portions with level difference include second portions with level difference each of which increases in height towards the central part of the fan in the axial direction, and in the at least one of the stabilizer and the rear guide, no protruding portion is formed in the vicinity of the second portions with level difference in the surface of the at least one of the stabilizer and the rear guide, surface that is opposite to the tangential fan.

In this air conditioner, because each second portion with difference in level increases in height towards the central part of the fan, the flow of air sucked into the fan does not change its direction towards the second portion with difference in level. Therefore, it is not necessary to provide an outstanding portion in the vicinity of the second portion with difference in level. When an outstanding portion is provided in the vicinity of each of all the portions with level difference, the air blow resistance is high and the air blow capacity may be impaired. In the present embodiment, because no outstanding portion is provided in the vicinity of each of the second portions with difference in level, deterioration of the air blowing capacity is prevented.

[Advantageous effects of the invention]

As described above, the following effects are obtained by the present invention.

According to the first aspect of the invention, at least one of the stabilizer and the rear guide has an outstanding portion that has an outstanding shape compared to its proximities and protrudes outward from the fan, in the vicinity of the first portion with difference in level which decreases in height towards the central part of the fan. For this reason, it is unlikely that the flow of air sucked into the fan will rise above the protruding portion. As such, the air flow is restricted in a concentrated manner in the curved portion of the vortex air flow generated between each of the first portions with level difference and the fan, and therefore the flow disturbance is restricted of vortex air. As a result, wind noise is suppressed. Also, because the portions with level difference in the front end portion of at least one of the stabilizer and the rear guide are provided, it is possible to make the fan blade pass the end portions in the axial direction of the portion with difference in level at different times or make the blade not pass the part between the portions with difference in level once since the height of this part between the portions with level difference gradually changes in the axial direction. As such, wind noise is suppressed by differentiating the wind noise generation moments in this way.

According to the second aspect of the invention, because the protruding portion is formed along the first portions with difference in level, it is possible to restrict the flow of air sucked into the fan that

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It rises above the first portions with level difference. With this, it is possible to effectively further restrict the air flow in the curved portion of the vortex air flow in a concentrated manner.

According to the third aspect of the invention, because the air flow sucked into the fan

Tangential tends to converge in the central part of the fan in the axial direction, it is further suppressed from

effectively disturbance of the vortex air flow when the protruding portion is provided in the vicinity of the first portion with a level difference as far from the central part of the fan in the axial direction.

According to the fourth aspect of the invention, because the air flow sucked into the fan

Tangential tends to converge in the central part of the fan in the axial direction, it is further suppressed from

effectively the disturbance of the vortex air flow when the farther an overhang portion of the central part of the fan is in the axial direction, the higher the overhanging height of the overhang portion will be.

According to the fifth aspect of the invention, the first portions with difference in level are easily formed because the first portions with difference in level extend linearly or in a curved manner through the whole in the axial direction.

According to the sixth aspect of the invention, because each first portion with difference in level changes in height in sections, the inclination of the first portion with difference in level is adjustable regardless of the length in the axial direction of the First portion with level difference.

According to the seventh aspect of the invention, because the height of the part between the adjacent parts of the portions with difference in level gradually changes in the axial direction, the blade does not pass through this part between the adjacent parts of portions with level difference at once. For this reason, when the blade passes through the part between the portions with difference in level, wind noise is generated, and therefore wind noise is suppressed continuously.

According to the eighth aspect of the invention, because in at least one of the stabilizer and the rear guide the height of the part between the portions with difference in level is constant in the axial direction, the stabilizer or the rear guide can form easily.

According to the ninth aspect of the invention, because every second portion with a difference in level increases in height towards the central part of the fan, the flow of air sucked into the fan does not change its direction towards the second portion with a difference of level. Therefore, it is not necessary to provide an outstanding portion in the vicinity of the second portion with difference in level. When an outstanding portion is provided in the vicinity of each of all the portions with level difference, the air blow resistance is high and the air blow capacity may be impaired. In the present embodiment, because no outstanding portion is provided in the vicinity of each of the portions with difference in level, deterioration of the air blowing capacity is prevented.

Brief description of the drawings

FIG. 1 is an oblique perspective of the external appearance of an indoor unit of an air conditioner in an embodiment of the present invention.

FIG. 2 is a cross section of the indoor unit.

FIG. 3 is an oblique perspective of a tangential fan.

FIG. 4 is a partially enlarged oblique perspective of the tangential fan.

FIG. 5 is an oblique perspective of the tangential fan and its proximities in the indoor unit.

FIG. 6 is a front view of the tangential fan and its proximities in the indoor unit.

FIG. 7 shows the tangential fan and its proximity to the indoor unit when viewed from above.

FIG. 8 (a) is a partially enlarged cross section of the front end of the rear guide and its proximities, which is taken in line A-A in FIG. 6 and FIG. 7. FIG. 8 (b) is a partially enlarged cross section of the front end of the rear guide and its proximities, which is taken in line B-B in FIG. 6 and FIG. 7.

FIG. 9 (a) is a partially enlarged cross section of the front end of the rear guide and its proximities, which is taken in line C-C in FIG. 6 and FIG. 7. FIG. 9 (b) is a partially enlarged cross section of the front end of the rear guide and its proximities, which is taken on the D-D line

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in FIG. 6 and FIG. 7.

FIG. 10 (a) is a partially enlarged cross section of a stabilizer and its proximities, which is taken in the A-A image in FIG. 6 and FIG. 7. FIG. 10 (b) is a partially enlarged cross section of the stabilizer and its proximities, which is taken in line B-B in FIG. 6 and FIG. 7.

FIG. 11 is an oblique perspective of a front end portion of the rear guide.

FIG. 12 is a partially enlarged view of FIG. eleven.

FIG. 13 is a partially enlarged oblique perspective of the front end portion of the rear guide.

FIG. 14 is an oblique perspective of a front guide.

FIG. 15 illustrates the air flow around a portion with difference in level of the rear guide.

FIG. 16: each of figures 16 (a) to 16 (f) shows a rear guide of another embodiment of the present invention, when viewed from above.

FIG. 17: each of FIGS. 17 (a) and 17 (b) shows a rear guide of another embodiment of the present invention, when viewed from above.

FIG. 18 is an oblique perspective of a rear guide of another embodiment of the present invention, when viewed from the fan side.

FIG. 19 is a partially enlarged oblique perspective of the rear guide of FIG. 18.

FIG. 20: each of FIGS. 20 (a) to 20 (c) shows a rear guide of another embodiment of the present invention, when viewed from above.

FIG. 21 shows a portion of known front tongue and a known fan, when viewed from above. Description of embodiments

Next, an embodiment of the present invention will be described.

As shown in FIG. 1, an indoor unit 1 of an air conditioner of the present embodiment is, in its entirety, narrow and long in a shaped direction, and is coupled to a wall of a room so that the length of the air conditioner is horizontal. The indoor unit 1 and an outdoor unit not illustrated constitute the air conditioner that cools or heats the room. Hereinafter, a direction of protrusion of the wall to which the indoor unit 1 is attached will be called "forward", while the opposite direction to the forward one will be referred to as "backward." In addition, the left-right direction in FIG. 1 will simply be called “left-right direction”.

As shown in FIG. 2, the indoor unit 1 includes a cover 2 and internal devices housed in the cover 2 such as a heat exchanger 3, a tangential fan 10, a filter 4, and an electronic component box (not shown). An inlet 2a is formed through the upper surface of the cover 2, while an outlet orifice 2b is formed through the lower surface of the cover 2. In the vicinity of the exit hole 2b, a horizontal flange 5 is provided to adjust the wind direction in the up-down direction and to open and close the exit hole 2b.

The tangential fan 10 (hereinafter simply referred to as a fan 10) is arranged so that its axial direction is parallel to the left-right direction. This fan 10 rotates in the direction indicated by the arrow in FIG. 2. On the front and on the rear of the fan 10, a front guide 30 and a rear guide 20 (rear tongue portion), respectively, are provided to form an air passage. A substantial upper half of the front guide 30 is constituted by a stabilizer 32 (front tongue portion). As the stabilizer 32 and the rear guide 20 are provided on the respective sides of the fan 10, the fan 10 sucks air from the upper front and blows the air down and back. The heat exchanger 3 is arranged to surround the front side and the upper side of the fan 10. In an air conditioning operation, the fan 10 is operated so that indoor air is sucked through the inlet port 2a, and heats or cools the air sucked into the heat exchanger 3 and then blows through the outlet orifice 2b.

The following will detail the fan 10, the rear guide 20 and the front guide 30.

[Fan]

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As shown in FIG. 3, the fan 10 is constituted by a plurality of blade rotors 12 (six in the present embodiment) aligned in the axial direction (left-right direction) and an end plate 11.

The end plate 11 constitutes the right end portion of the fan 10. From a central portion of the right surface of the end plate 11, a protrusion portion 11a protrudes to connect with the rotation axis of an engine (not shown) to operate the fan 10.

Of the six blade rotors 12, each of the five right blade rotors 12A is composed of blades 15 aligned in the circumferential direction and a substantially annular support plate 13 connected to the left ends of the blades. The blades 15 and the support plate 13 are formed jointly. The right end of each blade 15 of each blade rotor 12A is joined by welding or the like with the adjacent end plate 11 or the support plate 13 of the adjacent blade rotor 12A.

The leftmost blade rotor 12B of the six blade rotors 12 is composed of blades 15 aligned in the circumferential direction and a substantially disc-shaped end plate 14 that is connected to the left ends of the blades 15. The blades 15 and the end plate 14 are formed jointly. The right end of each blade 15 of the blade rotor 12b is joined by welding or the like with the adjacent blade rotor support plate 13 12A. From a central part of the left surface of the end plate 14, a shaft (not shown) that is rotatably supported by a bearing coupled to the cover 2.

The blades 15 of each blade rotor 12 extend in the axial direction (left-right direction), and each of which is arranged as a forward curved wing with a predetermined blade angle. The lengths of the blades 15 of each of the five blade rotors 12A are identical in the axial direction and are twice as substantially as long as the lengths of the blades 15 of the blade rotor 12B in the axial direction. In the present embodiment, the blades 15 of each blade rotor 12 are aligned in the circumferential direction at irregular intervals. The intervals of the blades 15 are identical between the six blade rotors 12. The blades 15 can be aligned at regular intervals.

As shown in FIG. 4, the blades 15 of a blade rotor 12 and the blades 15 of the adjacent blade rotor 12 deflect each other in the circumferential direction. To be more specific, blades 15 of any given blade rotor 12 are deflected from the blades 15 of the blade rotor 12 immediately to the left of any blade rotor 12 given each for an angle 0 in the direction of rotation (indicated by the arrow in FIG. 4). In other words, from the leftmost rotor 12 to the rightmost rotor 12 of the six blade rotors 12, each blade 15 deviates from the corresponding blade 15 of the adjacent blade rotor 12 an angle 0 in The direction of rotation.

[Rear Guider]

The rear guide 20 is provided at the rear of the fan 10, and the lower edge of the rear guide 20 is connected to the outlet hole 2b (see FIG. 2). As shown in FIG. 5 to FIG. 7, the length in the left-right direction of the rear guide 20 is substantially identical to the length in the left-right direction of the fan 10, and the rear guide 20 substantially opposes the entire fan 10 in the left-right direction . In addition, as shown in FIG. 2 and FIG. 6, the upper edge of the rear guide 20 is slightly higher in position than the upper end of the fan 10.

As shown in FIG. 2, on the surface of the rear guide 20, a surface that opposes the fan 10, a part other than the upper and lower end portions is a curved surface 21 that is substantially arc-shaped. The distance (shorter distance) between the curved surface 21 and the outer periphery of the fan 10 decreases upward.

In addition to the above, the rear guide 20 includes a protuberant portion 22 in a portion above the curved surface 21 (ie, at the front end side of the curved surface 21). The protuberant portion 22 is substantially arc-shaped and protrudes in the direction away from the fan 10 in cross-section taken on the orthogonal line to the leftmost direction. As shown in FIG. 9, the distance (shortest distance) between each protuberant portion 22 and the outer periphery of the fan 10 increases upwards. As described above, because the distance (shortest distance) between the curved surface 21 and the outer periphery of the fan 10 decreases upward, the rear guide 20 is closest to the fan 10 on a rim 20a (in hereinafter, closest position 20a) between the lower edge of each protruding portion 22 and the upper edge of the curved surface 21.

As shown in FIG. 11 and the like, the protuberant portion 22 is constituted by six folded portions 23 aligned in the left-right direction, five connecting portions 24 each of which is provided between two adjacent folded portions 23, two tilting attenuation portions 25 and a

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plurality of rib portions 26 (see FIG. 7 and FIG. 9).

Each of the six bent portions 23 is placed opposite the blade rotor 12. Of the six bent portions 23, the five right bent portions 23A are identical to each other in length in the left-right direction, and are identical to the blades 15 of blade rotors 12A in length in the left-right direction. The length of the left-most bent portion 23B is substantially identical to the length in the left-right direction of each of the blades 15 of the blade rotor 12B.

Each of the folded portions 23 is substantially arc in cross section in the orthogonal direction to the left-right direction. As shown in FIG. 11, in the circumferential direction of the fan 10, each folded portion 23 deviates from the axial direction of the fan 10 gradually from the left edge to the right edge. By virtue of this, the shape of each folded portion 23 is substantially uniform across any cross section orthogonal to the left-right direction. In addition, the height of the front end (upper front edge) of each folded portion 23 gradually changes in the left-right direction. In this specification, the heights of the folded portion 23, the connection portion 24, the inclination attenuation portion 25 and each of the portions with level difference 28a to 28e that will be mentioned later are not heights in the direction towards up-down if not heights along the direction in which the protuberant portion 22 protrudes (i.e. substantially forward and upward in the present embodiment). In addition, the highest ends of the six folded portions 23 are at the same height and the lower ends of the six folded portions 23 are at the same height (see FIGS. 6 and 7).

As shown in FIG. 8 (a), between the left edge and the right edge, each bent portion 23 is deflected an angle a1 in the direction opposite to the direction of rotation (indicated by the arrow in FIG. 8) of the fan 10. The angles a1 of the deviation of the six folded portions 23 are identical to each other. In addition to the above, as shown in FIG. 8 (b), the left edge of a folded portion 23 is deflected from the right edge of the folded portion 23 adjacent to the left of this folded portion 23 an angle p1 in the direction of rotation (indicated by the arrow in FIG. 9) of the fan 10. In addition, the angle p1 is identical to the angle a1.

As shown in FIG. 11 and the like, each of the five connection portions 24 connects end portions of two adjacent bent portions 23, end portions that are opposite each other in the left-right direction, between each other. Each connection portion 24 is substantially arc in cross section in the orthogonal direction to the left-right direction, and is substantially as thick as each folded portion 23. The leading end (upper front edge) of each connection portion 24 is extends linearly to decrease in height to the right. Each of the five connection portions 24 is positioned to oppose the support plate 13 of the fan 10 (see FIGS. 6 and 7).

As shown in FIG. 7 and the like, the two inclination attenuation portions 25 are connected to the front ends of the two left connection portions 24 of the five connection portions 24, respectively. These two portions of inclination attenuation 25 are identical in shape. As shown in FIG. 7, each tilt attenuation portion 25 extends substantially forward from the connection portion 24 and the upper front edge of the left end portion of the folded portion 23 provided to the left of this connection portion 24. The portion of Tilt attenuation 25 is substantially triangular in shape when viewed from above. The front end (front edge) of the tilt attenuation portion 25 extends substantially linearly and connects the left edge of the front end of the connection portion 24 with the front end of the folded portion 23. As shown in FIG. 6, the height of the front end (front edge) of the inclination attenuation portion 25 decreases to the right. The length in the left-right direction of the inclination attenuation portion 25 is preferably 5% to 30% of the total length of the folded portion 23 and the connection portion 24 in the left-right direction.

As shown in FIG. 9 (b), the inclination attenuation portion 25 is substantially triangular in cross section in the orthogonal direction to the axial direction. The rear face of the inclination attenuation portion 25 extends substantially upwardly from the upper surface of the bent portion 23 or the connection portion 24, and the upper surface of the inclination attenuation portion 25 extends substantially forward from the upper edge of the rear face of the inclination attenuation portion 25. The front edge of the inclination attenuation portion 25 is substantially as thick as the bent portion 23 and the connection portion 24.

As shown in FIG. 7, the rib portions 26 extend backward from the rear face of the tilt attenuation portion 25. As shown in FIG. 9, each rib portion 26 is provided to protrude from the rear face (which is opposite the fan 10) of the folded portion 23 or the connection portion 24. The height in the up-down direction of the front edge of the rib portion 26 is substantially identical to the height in the up-down direction of the upper edge of the rear face of the inclination attenuation portion 25. The thickness of the rib portion 26 decreases backwards.

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On the surface of the protuberant portion 22, surface that is on the side opposite the fan 10, the inclination attenuation portion 25 and the rib portion 26 protrude in shape compared to their surroundings (the folded portion 23 and the portion of connection 24). This protruding part is called the protruding portion 27. The range of the protruding portion 27 when viewed from above is identical to the range occupied by the inclination attenuation portion 25 and the rib portions 26.

The height of the protruding portion 27 in a direction D (see FIG. 9) that is substantially orthogonal to the surface of the protruding portion 22, a surface that is opposite the fan 10 is called the protruding height. The highest position 27a of the projecting height of the projecting portion 27 (hereinafter referred to as vertex 27a) corresponds to the right edge of the connection portion 24, at the upper edge of the rear face of the inclination attenuation portion 25. As shown in FIG. 13, the projecting height of a portion of the projecting portion 27, part that is to the right of the vertex 27a, decreases to the right, while the projecting height of a portion of the projecting portion 27, part that is to the left of the vertex 27a, decreases rapidly to the left.

Because the opposite end portions in the left-right direction of two adjacent folded portions 23 are different in height, five portions with level difference 28a to 28e are formed at the leading end of the protuberant portion 22 to align in the left-right direction. The height of each of the portions with level difference 28a to 28e decreases to the right. The portions with difference of level 28a to 28c are provided to the left of a central part M in the axial direction of the fan 10 (see FIG. 6 and FIG. 7), while the portions with difference of level 28d and 28e they are provided to the right of the central part M in the axial direction of the fan 10. Each of the portions with level difference 28a and 28b is the leading end of the inclination attenuation portion 25, while each of the portions with

Level difference 28c to 28e is the leading end of the connection portion 24.

The highest points (left edges) of the five portions with level difference 28a to 28e are identical in height. The lowest points (right edges) of the portions with level difference 28c to 28e, which are the front ends of the connection portions 24, are identical in height. The lowest points (right edges) of the difference-level portions 28a and 28b, which are the front ends of the inclination attenuation portions 25, are identical in height and are higher than the lowest points of the portions with level difference 28c to 28e.

As shown in FIG. 12, an angle of inclination of each of the portions with difference of level 28a and 28b with respect to the axial direction is called angle ^ 1, while an angle of inclination of each of the portions with difference of level 28c to 28e with respect to the axial direction is called angle ^ 2. He

angle ^ 1 is smaller than angle ^ 2. In other words, the inclination of each portion with

Level difference 28a and 28b is smoother than the inclination of each of the portions with level difference 28c to 28e.

In addition to the above, as shown in FIG. 12, a variation in height in a predetermined length W in the left-right direction from the highest point in each of the portions with difference of level 28a and 28b is called AH1. In addition, a variation in height in the predetermined length W in the left-right direction from the highest point in each of the portions with level difference 28c to 28e is called AH2. The AH1 variation is smaller than the AH2 variation. "The variation in height in the predetermined length W in the left-right direction (axial direction)" is a measure for a comparison between inclinations of portions with level difference. The length W is not limited to the length shown in FIG. 12. In the present embodiment, the length W is only required to be shorter than the length in the left-right direction of each of the portions with level difference 28a and 28b. In addition, in the present embodiment, the starting point of the length W in the left-right direction is the highest point of each portion with difference in level. However, the starting point may not be the highest point in the portion with level difference.

[Front guide]

The front guide 30 is provided on the front of the fan 10, and the lower edge of the front guide 30 is connected to the outlet hole 2b (see FIG. 2). The front guide 30 is composed of the stabilizer 32 provided to oppose the fan 10 and a front wall portion 31 extending from the bottom edge of the stabilizer 32 to the outlet hole 2b.

As shown in FIG. 5 to FIG. 7, the length in the left-right direction of the stabilizer 32 is substantially identical to the length in the left-right direction of the fan 10, and the stabilizer 32 substantially opposes the entire fan 10 in the left-right direction. In addition, as shown in FIG. 2 and FIG. 6, the upper edge of the stabilizer 32 is in a lower position than the center of the fan 10.

As shown in FIG. 14, on the surface of the stabilizer 32, surface opposing the fan 10,

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A part that is not the upper and lower end portions is a curved surface 33 which is substantially arc-shaped. The distance (shorter distance) between the curved surface 21 and the outer periphery of the fan 10 decreases upward. In addition, the stabilizer 32 includes a bending surface 34 that curves substantially forward from the lower edge of the curved surface 33. The lower edge of the bending surface 34 is connected to the front wall portion 31.

In addition to the above, the stabilizer 32 includes a flat end face 35 that extends downward and forward from the upper edge of the curved surface 33 and a convex portion 36 that is provided at the front of the end face 35 and protrudes upward from the end face 35. The convex portion 36 and the end face 35 constitute the upper end portion of the rear guide 20. The cross-sectional shape of the convex portion 36 in the orthogonal direction to the left direction -Right is substantially triangular. As shown in FIG. 14, the stabilizer 32 is closest to the outer periphery of the fan 10 at an upper edge 32a (hereinafter, closest position 32a) of the curved surface 33.

The stabilizer 32 (which includes the convex portion 36, the end face 35, the curved surface 33 and the bending surface 34) is composed of six bent portions 37 aligned in the left-right direction and five connection portions 38 each of which 37 adjacent bent portions are provided between two.

Each of the six bent portions 23 is placed to oppose the blade rotor 12. Of the six bent portions 23, the five right bent portions are identical to each other in length in the left-right direction, and are identical to the blades 15 of blade rotors 12A in length in the left-right direction. The length of the leftmost bent portion is substantially identical to the length in the left-right direction of each of the blades 15 of the blade rotor 12B.

As shown in FIG. 11, in the circumferential direction of the fan 10, each folded portion 23 deviates from the axial direction of the fan 10 gradually from the left edge to the right edge. By virtue of this, the shape of each folded portion 23 is substantially uniform across any cross section orthogonal to the left-right direction. The height of the front end (upper edge) of each folded portion 37 gradually changes in the left-right direction. In addition, the highest ends of the six folded portions 23 are at the same height and the lower ends of the six folded portions 23 are at the same height (see FIG. 6).

As shown in FIG. 10 (a), between the left edge and the right edge, each folded portion 37 deflects an angle a2 in the direction opposite to the direction of rotation (indicated by the arrow in FIG. 11) of the fan 10. The angles a2 of the deviation of the six folded portions 37 are identical to each other In addition to the above, as shown in FIG. 11 (b), the left edge of a folded portion 37 deflects from the right edge of the folded portion 37 adjacent to the left of this folded portion 37 an angle p2 in the direction of rotation (indicated by the arrow in FIG. 10) of the fan 10. In addition, the angle p2 is identical to the angle a2.

As shown in FIG. 6 and FIG. 7, each of the five connection portions 38 connects the end portions of two adjacent bent portions 37, end portions that oppose each other in the left-right direction. Each of the connection portions 38 is positioned to oppose the support plate 13 of the fan 10. Because the end portions of two adjacent bent portions 37, end portions that oppose each other in the left direction right, they are different in height, five portions with level difference are formed at the front end of the stabilizer 32 to align in the left-right direction.

Now, the air flowing in the separation distance between the rear guide 20 and the fan 10 when the air conditioner is operated will be described. As the fan 10 is operated, a vortex air flow (indicated by the arrow in FIG. 8 (b)) is generated between the front end portion of the rear guide 20 and the fan 10. In FIG. 15, the center C of the vortex air flow is indicated by a line of dots and dashes. As shown in FIG. 15, the vortex air flow is curved in an area formed by the edges in the axial direction of each of the portions with level difference 28a to 28e and the fan 10.

When a vane 15 passes the vortex air flow formed between the rear guide 20 and the fan 10, wind noise is generated as a result of the interference between the vortex air flow and the vane 15. Because each portion bent 23 deviates from the rear guide 20 gradually in the circumferential direction of the left-right direction, wind noise is generated continuously while the blade 15 passes through a bent portion 23. Also, because of the two end portions of two adjacent bent portions 23, end portions that oppose each other in the left-right direction, deviate between the angle p1 in the circumferential direction, wind noise is generated at different times in the end portions of two adjacent 23 bent portions , end portions that oppose each other in the left-right direction, when the angle 0 of deflection of the blade rotor 12 is different from the angle p1 (= a1). As such, wind noise is suppressed by differentiating the moments of wind noise generation in this way.

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In the wind speed distribution of the fan 10 on the blowing side, the wind speed increases towards the central part in the axial direction of the fan 10. For this reason, as indicated by the arrows in FIG. 7, the flow of air sucked into the fan 10 tends to converge in the central part M in the axial direction of the fan 10. For this reason, as long as no protruding portion 27 is provided in the vicinity of the portions with difference of level 28a and 28b, the air flow tends to change its direction towards each of the portions with difference of level 28a and 28b, with the result that the air flows in a concentrated manner in the curved portion of the air flow of vortex. Consequently, the vortex air flow is disturbed and, therefore, the wind noise increases.

Meanwhile, in the present embodiment, the projecting portion 27 protruding away from the fan 10 in comparison to the folded portion and the connection portion 24, is provided in the vicinity of each of the portions with level difference 28a and 28b For this reason, as shown in FIG. 15, it is unlikely that the air flow will change its direction to each of the portions with a difference in level 28a and 28b and the air flow that passes through the range of the protruding portion 27 is reduced. Because the air fluid is restricted in the curved portion of the vortex air flow in a concentrated manner, the disturbance of the vortex air flow is restricted.

In addition to the above, in the present embodiment, the angle ^ 1 of inclination of each of the portions with difference of level 28a and 28b is smaller than the angle of inclination ^ 2 of each of the other portions with difference from level 28c to 28e. For this reason, in comparison with the case in which the angle of inclination of each of the portions with difference of level 28a and 28b is identical to angle ^ 2 (that is, in which no proportion of inclination attenuation is provided 25), it is unlikely that the air flow will change its direction to each of the portions with a level difference 28a and 28b, and the air fluid in the curved portion of the vortex air flow is further restricted. Also, because the angle of inclination of each of the portions with difference in level 28a and 28b is small, the degree of flexion of the curved portion of the vortex air flow is smooth, and therefore the flow of Vortex air looks less disturbed.

In addition to the above, the vortex air flow (indicated by the arrow in FIG. 8 (b)) is generated between the front end portion of the stabilizer 32 and the fan 10, and the wind noise is generated as that the vortex air flow and the blade 15 interfere with each other when the blade 15 passes the vortex air flow. Because the bent portion 37 of the stabilizer 32 linearly deviates from the left-right direction in the circumferential direction, wind noise is generated continuously when the blade 15 passes through a bent portion 37. In addition, Because the opposite end portions in the left-right direction of the two adjacent bent portions 37 deviate from each other p2 in the circumferential direction, wind noise is generated at different times in the end portions of two bent portions 23 adjoining, end portions that oppose each other in the left-right direction, when the angle 0 of deflection of the blade rotor 12 is different from the angle p2 (= a2). As such, wind noise is suppressed by differentiating the moments of wind noise generation in this way.

The air conditioner of the present embodiment has the following characteristics.

Because the rear guide 20 includes the projecting portion 27 protruding outward from the fan 10 in the vicinity of each of the portions with level difference 28a and 28b that decreases in height towards the central part M in the axial direction of the fan 10, it is unlikely that the air flow sucked into the fan 10 will rise above the protruding portion 27. As such, the air fluid is restricted in a manner concentrated on the curved portion of the vortex air flow generated between each of the portions with difference of level 28a and 28b and the fan, and therefore the disturbance of the vortex air flow is restricted. As a result, wind noise is suppressed.

In addition to the above, because in the present embodiment the height of a part (folded portion 23) between the adjacent parts of the portions with difference in level 28a to 28e gradually changes in the axial direction, the blade 15 does not it passes through this part between the adjacent parts of the portions with difference of level 28a to 28e at once. For this reason, when the blade 15 passes through the part between the adjacent parts of the portions with level difference 28a to 28e, wind noise is generated and, therefore, the wind noise is suppressed continuously.

In addition to the above, because the height of each of the portions with difference in level 28d and 28e (second portions with difference in level) increases towards the central part M in the axial direction of the fan 10, the air flow sucked into the fan 10 does not change its direction towards each of the portions with level difference 28d and 28e. Therefore, it is not necessary to provide an outstanding portion in the vicinity of each of the portions with level difference 28d and 28e. If an outstanding portion is provided in the vicinity of each of all portions 28a to 28e with difference in level, the air blowing capacity may be impaired as a result of high air blow resistance. In the present embodiment, because no outstanding portion is provided in the vicinity of each of the portions

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with difference of level 28d and 28e, the deterioration of the air blowing capacity is prevented.

In addition to the above, because the air flow sucked in the fan 10 tends to converge in the central part M in the axial direction of the fan 10, the disturbance of the vortex air flow is further restricted since the protruding portion 27 is provided in the vicinity of the portion with difference in level 28a which is the closest to the end portion in the axial direction of the fan 10.

Furthermore, because in the present embodiment the protruding portion 27 is also provided in the vicinity of the level difference portion 28b which is the second closest to the end portion in the axial direction of the fan 10, the Disturbance of the vortex air flow is further restricted. In addition to the above, in the present embodiment, no protruding portion is provided in the vicinity of the portion with difference in level 28c, which decreases in height towards the central part M in the axial direction of the fan 10. With respect to this, because the level difference portion 28c is close to the central part M in the axial direction of the fan 10, the direction of the air flowing around the level difference portion 28c is substantially orthogonal to the axial direction , and the air flow hardly changes its direction towards the portion with difference of level 28c. In the present embodiment, the deterioration in the air blowing capacity is restricted because no protruding portion is provided in the vicinity of the portion with difference in level 28c.

In addition to the above, because in the present embodiment, the projecting portion 27 is formed along each of the portions with difference in level 28a and 28b, it is possible to restrict the flow of air sucked into the fan 10 that rises above each of the portions with difference of level 28a and 28b. In this way, the air fluid is further effectively restricted in a manner concentrated in the curved portion of the vortex air flow.

In addition to the foregoing, in the present embodiment, the height variation of each of the portions with level difference 28a and 28b within the predetermined length in the axial direction is smaller than the variation in height of each of the other portions with difference of level 28c to 28e. As long as the variation in height of each of the portions with difference of level 28a and 28b is identical to that of each of the portions with difference of level 28c to 28e, the air flow tends to change its direction towards each of the portions with difference of level 28a and 28b around each of the portions with difference of level 28a and 28b, with the result that disturbance in the curved portion of the vortex air flow is unlikely. With respect to this, in the present embodiment, because the variation in height of each of the portions with difference in level 28a and 28b is small, it is possible to restrict the flow of air sucked into the fan 10 by changing its direction to each of the portions with level difference 28a and 28b. This further restricts the air flow in a concentrated manner in the curved portion of the vortex air flow generated between each of the portions with level difference 28a and 28b and the fan 10.

Although the embodiment of the present invention has been described, it should be noted that the scope of the invention is not limited to the embodiment described above. The scope of the present invention is defined by the appended claims rather than by the description of the previous embodiment, and the present invention is intended to cover all alternatives, modifications and variants that are within the scope of the appended claims. It is noted that the following modifications can be combined and implemented properly.

Although in the above embodiment two bent portions 23 are connected adjacent to each other by a connection portion 24, no connection portion 24 of this type and the end portions of two adjacent bent portions 23, end portions that are connected, may be provided. they oppose each other in the axial direction, they can be connected directly to each other as shown in FIG. 16 (a) to FIG. 16 (f). In this case, a portion with difference in level for which no inclination attenuation portion is provided (for example, a portion with difference in level 128e shown in FIG. 16 (a) to FIG. 16 (f) ) is constituted by the leading end portion of the highest of the opposite end portions of two adjacent bent portions 23, and is orthogonal to the axial direction.

The shape of each of the portions with difference in level 28a and 28b may be different from the manner described in the previous embodiment.

For example, a portion with difference in level may extend in a curved manner from the highest point to the lowest point, as in a portion with difference in level 128a indicated by the thick line in FIG. 16 (a).

In addition, the height of a portion with difference in level may change in sections as in portions with difference in level 228a to 628a and 828a indicated by the thick lines in FIG. 16 (b) to FIG. 16 (f) and FIG. 17 (b). In this way, the inclination of the portion with difference in level is adjustable regardless of the length in the axial direction of the portion with difference in level.

In the portions with difference of level 228a and 828a in FIG. 16 (b) and FIG. 17 (b), the edge portion that extends linearly or curved from the highest point is smooth in inclination compared

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with the portion with level difference 128e (second portion with level difference) that increases in height towards the central part in the axial direction of the fan (i.e., the variation in height within the predetermined length in the axial direction is small) . This arrangement restricts the flow of air sucked into the fan 10 which changes its direction towards each of the edge portions of the portions with difference in level 228a and 828a described above. It is noted that the predetermined length in the axial direction is, for example, shorter than the length in the axial direction of each of the portions with level difference 228a and 828a from the highest point of each of the portions with difference of level 228a, 828a and 128e.

In addition to the above, in each of the portions with difference of level 328a to 628a shown in FIG. 16 (c) to FIG. 16 (f), the angle of inclination of the edge portion that extends linearly or in a curved manner from the highest point is identical to the angle of inclination of the portion with level difference 128e (second portion with level difference ) which increases in height towards the central part in the axial direction of the fan, and this edge portion is shorter than the edge portion that extends linearly from the highest point of the portion with level difference 128e. This arrangement restricts the flow of air sucked into the fan 10 which changes its direction around the edge portion of each of the portion with difference in level 328a to 628a. It is noted that the predetermined length in the axial direction is, for example, longer than the length in the axial direction of the edge portion of each of the portions with level difference 328a to 628a from the highest point of each of the portions with difference of level 328a to 628a and 128e.

In addition to the above, while in the previous embodiment the portions with level difference 28a and 28b are identical to the portions with level difference 28d and 28e (second portions with level difference) at the height of the highest point, the height of the highest points of the portions with difference of level 28a and 28b may be different from the height of the highest point of the portion with difference of level 128e (second portion with difference of level), as in the portions with difference of level 728a and 828a indicated by the thick lines in FIG. 17 (a) and FIG. 17 (b).

Although in the previous embodiment the two portions with level difference 28a and 28b are identical in the variation in height AH1 within the predetermined length W in the axial direction, these portions may be different in the variation. In such a case, to restrict the disturbance of the vortex air flow, the variation in height of the portion with difference in level 28a which is the furthest from the central part M in the axial direction of the fan 10 is preferably arranged to be more smaller than the variation in height of the portion with difference of level 28b.

In the previous embodiment, the portions with difference of level 28a and 28b of the three portions with difference of level 28a to 28c, each of which decreases in height towards the central part M in the axial direction of the fan 10, are smaller than the portions with difference in level 28d and 27e that increase in height towards the central part M in the axial direction of the fan 10, in terms of the variation in height in the predetermined length in the axial direction. Alternatively, all three portions with difference of level 28a to 28c may be smaller than portions with difference of level 28d and 28e in terms of the variation in height.

In addition to the above, only one of the portions with difference of level 28a and 28b may be smaller than the portions with difference of level 28d and 28e in terms of the variation in height, and the other of the portions with difference of level 28a and 28b can be identical to portions with difference of level 28d and 28e in terms of the variation in height. In such a case, to restrict the disturbance of the vortex air flow, the variation in height of the portion with difference in level 28a which is the furthest from the central part M in the axial direction of the fan 10 is preferably arranged to be more smaller than the variation in height of the portion with difference of level 28b.

Although in the previous embodiment the number of the portions with level difference 28a to 28e provided in the rear guide 20 is identical to the number of the support plates 13 and the portions with level difference 28a to 28e are arranged to oppose the respective support plates 13, the present invention is not limited to this arrangement. The number of the portions with level difference may be different from the number of the support plates 13. In addition, the portions with level difference may not be arranged to oppose the respective support plates 13.

Although in the previous embodiment the folded portion 23 is provided between the adjacent parts of the portions with level difference 28a to 28e and the leading end of the folded portion 23 gradually changes in height in the axial direction, a part between the parts adjoining portions with level difference 928a to 928e and 929a to 929e may be constant in height in the axial direction, such as in a rear guide 920 shown in FIG. 18 and FIG. 19, for example. The rear guide 920 is easily formed in this case.

As shown in FIG. 18, a protruding portion 922 of the rear guide 920 has an arc in cross section in the orthogonal direction to the axial direction and, high portions and low portions alternately line up in the axial direction. In other words, at the front end of the rear guide 920, the portions with level difference 928a to 928e each of which decrease in height towards one end in the axial direction of the fan 10 and the portions with level difference 929a to 929e each of which increases

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in height towards the end in the axial direction of the fan 10 they alternately line up in the axial direction. Of the portions with level difference 928a to 928c and 929c to 929e (first portions with level difference) each of which decreases in height towards the central part M in the axial direction of the fan 10, four portions with level difference 928a , 928b, 929d and 929e that are near the ends in the axial direction of the fan 10 are smaller than the portions with level difference 928d, 928e, 929a and 929b (second portions with level difference) each of which increases in height towards the central part M in the axial direction of the fan 10, in terms of the variation in height within a predetermined length in the axial direction. The predetermined length in the axial direction is, for example, shorter than the length in the axial direction of each of the portions with level difference 928a, 928b, 929d and 929e from the highest point of each of the portions with level difference 928a to 928e and 929a to 929e. In addition to the above, as shown in FIG. 19, on the surface of the protruding portion 922, surface that is on the side opposite the fan 10, an outstanding portion 927 is formed in the vicinity of each of the portions with level difference 928a, 928b, 929d and 929e. The projecting height of this projecting portion 927 decreases towards the central part M in the axial direction of the fan 10.

The shape of the protruding portion 27 is not limited to the form described in the previous embodiment, and it is only required to protrude away from the fan 10 compared to the proximities of the protruding portion 27.

Although in the previous embodiment two protruding portions 27 are identical in protruding height, they can be different in protruding height. In such a case, restricting the disturbance of the vortex air flow, the protruding height of the protruding portion 27 which is furthest from the central part M in the axial direction of the fan 10 is preferably arranged to be higher than the protruding height from the other outstanding portion 27.

Although in the above embodiment the protruding portion 27 is provided in the vicinity of each of the portions with difference in level 28a and 28b, no protruding portion 27 can be provided in the vicinity of only one of the two portions with difference Level 28a and 28b. In other words, the surface on the side opposite the fan 10 of one of the two inclination attenuation portions 25 may not protrude in comparison with the folded portion 23 and the connection portion 24. For the purpose of restricting the disturbance of the Vortex air flow, the protruding portion 27 is preferably provided in the level difference portion 28a which is furthest from the central part M in the axial direction of the fan 10.

In the previous embodiment, the inclination of each of the portions with level difference 28a and 28b in the vicinity of the projecting portion 27 is smoother than the inclination of each of the portions with level difference (second portions with level difference) 28d and 28e which increase in height towards the central part M in the axial direction of the fan 10 (ie, the variation in height within the predetermined range in the axial direction is small). In this regard, as shown, for example, in FIG. 20 (a) to FIG. 20 (c), the variation in height of each of portions with level difference 1028a, 1128a and 1228a in the vicinity of each of the outstanding portions 1027, 1127 and 1227 may be equal to the variation in height of the portion with level difference 128e (second portion with level difference) that increases in height towards the central part M in the axial direction of the fan 10. In FIG. 20 (a) to FIG. 20 (c), the ranges of the protruding portions 1027, 1127 and 1227 are shaded.

In addition to the foregoing, although in the above embodiment the protruding portion 27 is formed along each of the portions with difference in level 28a and 28b, the range of the formation of the protruding portion 27 is not limited to this. . The protruding portion can be formed differently as long as the protruding portion is formed in the vicinity of a portion with a difference in level that decreases in height towards the central part M in the axial direction of the fan 10 and in a part where it can be reduced the amount of air flowing in the curved portion of the vortex air flow. For example, as in the protruding portion 1127 shown in FIG. 20 (b), an outstanding portion may be formed only around the lower part of the portion with lower level difference 1128a. Also, for example, as in the protruding portion 1227 shown in FIG. 20 (c), an outstanding portion may be formed only around the highest part of the portion with the highest level difference 1228 (a). In any of the modifications, the air flowing in the curved portion of the vortex air flow is reduced.

Although in the above embodiment the portions with difference in level provided at the front end of the stabilizer 32 are identical to each other in inclination, the portions with difference in level of the stabilizer 32 may be different from each other in inclination, as well as in the guide rear 20 (that is, they can be different from each other in the variation in height in the predetermined length in the axial direction). To be more specific, the variation in height of at least one of the portions with level difference each of which decreases in height towards the central part M in the axial direction of the fan 10 is arranged to be smaller than the variation in height of the portions with difference in level each of which increases in height towards the central part M in the axial direction of the fan 10. In addition, the portions with difference in level are different from each other in inclination only in one of the rear guide 20 and stabilizer 32.

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In addition to the foregoing, although in the above embodiment no protruding portion is provided in the vicinity of each of the difference-level portions provided at the front end of the stabilizer 32, an outstanding portion may be provided in the vicinity of a portion with level difference of the stabilizer 32, as well as in the rear guide 20. To be more specific, an outstanding portion is provided that protrudes away from the fan 10 compared to the proximities in the vicinity of at least one of the portions with difference each one of which decreases in height towards the central part M in the axial direction of the fan 10.

In addition, an outstanding portion can be provided in only one of the rear guide 20 and the stabilizer 32.

Although the above embodiment describes a case in which the present invention is used in a wall-mounted indoor unit that is arranged to suck indoor air from an upper part of the indoor unit and blow the air from a lower part of the purposes . For example, the present invention provides for sucking indoor air from a top of the indoor unit.

Industrial applicability

The present invention makes it possible to suppress the vortex.

List of reference numbers

1 Indoor unit of air conditioner 10 Tangential fan 20, 920 Rear guide

25 Tilt attenuation portion

26 Serving portion 27, 927 Outstanding portion 27a Vertice

28a to 28c, 128a, 228a, 328a, 428a, 528a, 628a, 728a, 828a, 928a to 928c, 929c to 929e, 1028a, 1128a, 1228a Portion with level difference (first portion with level difference)

28d, 28e, 128e, 928d, 928e, 929a, 929b Portion with level difference (second portion with level difference)

32 Stabilizer

indoor unit, the present invention can be applied to others can be used in a floor-mounted indoor unit that is lower part of the indoor unit and blow the air from one part

wind noise restricting the disturbance of an air flow of

Claims (9)

10 fifteen twenty 2. 25 3. 30 Four. 35 5. 40 6. 7. Four. Five fifty 8. 55 9. 60 Air conditioner comprising: a tangential fan (10); Y a stabilizer (32) and a rear guide (20) which are provided on respective sides of an outer periphery of the tangential fan (10) to form an air duct, having at least one of the stabilizer (32) and the rear guide (20), in a front end portion, portions with level difference (28a-28c) that are aligned in an axial direction of the fan and include first portions with difference of level (28a-28c) each of which decreases in height towards a central portion (M) in the axial direction of the fan (10); an protruding portion (27) being formed in the vicinity of at least one of the first level difference portions (28a, 28b) on a surface of the at least one of the stabilizer (32) and the rear guide (20), surface that is opposite to the tangential fan (10), characterized by: the protruding portion (27) has an outstanding shape compared to its surroundings and protrudes outward from the fan. Air conditioner according to claim 1, wherein the protruding portion (27) is formed along the first portions with level difference (28a-28c). Air conditioner according to claim 1 or 2, wherein the protruding portion (27) is provided in the vicinity of a first portion with level difference (28a) which is the furthest in the axial direction from the central portion (M) of the fan, of the first portions with level difference. Air conditioner according to any one of claims 1 to 3, wherein at least one of the stabilizer (32) and the rear guide (20) also includes one or more projecting portions (27), and the two or more portions protrusions (27) are arranged so that the protruding height of each protruding portion (27) increases with increasing distance from the central portion (M) of the fan in the axial direction. Air conditioner according to any one of claims 1 to 4, wherein each of the first level difference portions (28a-28c) extends linearly or in a curved manner from the highest point to the point lower. Air conditioner according to any one of claims 1 to 4, wherein the height of each of the first portions with level difference (28a, 28c) changes in sections. Air conditioner according to any one of claims 1 to 6, wherein two first portions with level difference (28a, 28b), of the first portions with level difference (28a-28c), are provided to collide between sf, and the height of a part between the two adjacent level difference portions (28a, 28b) gradually changes in the axial direction. Air conditioner according to any one of claims 1 to 6, wherein a level difference portion (28d) that increases in height towards the central portion (M) of the fan (10) in the axial direction is provided in the proximity of one of the first portions with level difference (28c), and the height of a part between the two portions with adjacent level difference is constant in the axial direction. Air conditioner according to any one of claims 1 to 8, wherein the portions with level difference include second portions with level difference (28d, 28e) each of which increases in height towards the central portion (M ) of the fan (10) in the axial direction, and in the at least one of the stabilizer (32) and the rear guide (20), no protruding portion (27) is formed in the vicinity of each of the second level difference portions (28d, 28e) on the surface of the at least one of the stabilizer (32) and the rear guide (20), surface that is opposite to the tangential fan (10).