WO2019012578A1

WO2019012578A1 - Indoor unit for air conditioner

Info

Publication number: WO2019012578A1
Application number: PCT/JP2017/025133
Authority: WO
Inventors: 池田　尚史; 平川　誠司; 祥吾生田目; 貴紀吉田; 代田　光宏
Original assignee: 三菱電機株式会社
Priority date: 2017-07-10
Filing date: 2017-07-10
Publication date: 2019-01-17
Also published as: JPWO2019012578A1; CN110914550B; JP6811863B2; CN110914550A

Abstract

An indoor unit for an air conditioner is provided with a cross flow fan. An impeller of the cross flow fan has a plurality of blades each having a first end part and second end part as end parts along the direction of a rotary shaft, and a support panel that supports the first end parts of each of the plurality of blades. The second end parts are disposed farther forward in the rotational direction of the impeller than the first end parts. Each of the plurality of blades has an inner peripheral end part and an outer peripheral end part as end parts along a radial direction centered around the rotary shaft. The wall thickness of the inner peripheral end parts is greater than that of the outer peripheral end parts. Each of the plurality of blades has, toward the inner peripheral end part from a straight line that passes through a center point of a chord line of each of the plurality of blades and is perpendicular to the chord line, a maximum-wall-thickness part where the wall thickness reaches a maximum.

Description

Indoor unit of air conditioner

The present invention relates to an indoor unit of an air conditioner provided with a cross flow fan.

Patent Document 1 describes a cross-flow fan in which a plurality of impellers are stacked in the rotation center line direction. Each of the plurality of impellers includes a support plate and a plurality of vanes formed on the main surface of the support plate. The cross section perpendicular to the rotation center line in each blade portion decreases in the direction from the root to the tip. Further, the center of the cross section perpendicular to the rotation center line in each blade portion is displaced forward in the rotational direction as it goes from the root portion to the tip portion, and is displaced radially outward. .

JP, 2010-101222, A

In each cross-section fan of the cross-flow fan described in Patent Document 1, the thickness of the central portion between the outer end portion and the inner end portion in the cross section perpendicular to the rotation center line is approximately the maximum thickness. The wall thickness becomes smaller as it goes away and approaches the outer end portion or the inner end portion, and both the outer end portion and the inner end portion have a thickness distribution in which the wall thickness becomes minimum. If each blade portion of the cross flow fan has such a thickness distribution, the flow of air is likely to be separated from the blade surface, and there is a problem that the efficiency of the cross flow fan may be lowered. .

The present invention is made to solve the problems as described above, and it is an object of the present invention to provide an indoor unit of an air conditioner that can improve the efficiency of the cross flow fan.

An indoor unit of an air conditioner according to the present invention is an indoor unit of an air conditioner including a casing in which an inlet and an outlet are formed, and a cross flow fan housed in the casing, and the cross The flow fan includes an impeller disposed in an air passage formed in the casing, a stabilizer that divides the air passage into a suction side air passage and an outlet side air passage, and the air passage side from the impeller. A guide wall for guiding the air blown out to the air outlet, and the impellers are respectively disposed on a circumference centered on a rotation axis of the impeller, and a direction along the rotation axis A plurality of wings each having a first end and a second end as an end of the second support, and a support plate for supporting the first end of each of the plurality of wings, the second end A portion of the impeller that is closer to the first end than the first The plurality of wings are disposed forward in the rolling direction, and each of the plurality of wings has an inner peripheral end and an outer peripheral end as radial ends centered on the rotation axis, and the second The cross-sectional area of the end in a cross section perpendicular to the axis of rotation is smaller than the cross-sectional area of the first end in a cross section perpendicular to the axis of rotation, and the axis of rotation and the second end The distance between the outer peripheral end portion of the first end portion and the outer peripheral end portion is shorter than the distance between the rotary shaft and the outer peripheral end portion at the first end portion. The distance from the circumferential end is longer than the distance between the rotation axis and the inner circumferential end at the first end, and in the cross section perpendicular to the rotation axis, the inner circumferential end The thickness of the portion is greater than the thickness of the outer peripheral end, and in the cross section perpendicular to the rotation axis, each of the plurality of wings is Having a thickest portion with the largest thickness on the inner peripheral end side of a straight line passing through the midpoints of the chord lines of the plurality of wings and perpendicular to the chord line It is.

On the suction side of the impeller, air flows from the outer peripheral end of the blade toward the inner peripheral end. In the present invention, since the largest thickness portion is formed on the inner peripheral side of the wing, even if the air flow is likely to be separated from the wing surface on the outer peripheral side of the wing, the maximum wing thickness decreases. Peeling can be suppressed at the thick part.
On the outlet side of the impeller, air flows from the inner circumferential end to the outer circumferential end of the wing. On the outlet side of the impeller, the inflow angle of air to the blade is more likely to change than the suction side of the impeller due to the fluctuation of the flow. In the present invention, since the thickness of the inner peripheral end which is the front edge is larger than the thickness of the outer peripheral end, it is possible to prevent separation from occurring even if the inflow angle of air changes. it can.
Therefore, according to the indoor unit of the air conditioner according to the present invention, the efficiency of the cross flow fan can be improved.

It is an external appearance perspective view which shows the structure of the indoor unit 100 of the air conditioner concerning Embodiment 1 of this invention. It is a side view which shows the internal structure of the indoor unit 100 of the air conditioner concerning Embodiment 1 of this invention. It is an external view which shows the structure of the impeller 8a and the motor 12 in the indoor unit 100 of the air conditioner concerning Embodiment 1 of this invention. It is an external appearance perspective view which shows the structure of the impeller single-piece | unit 8d in the indoor unit 100 of the air conditioner concerning Embodiment 1 of this invention. It is a side view which shows the structure of the impeller single-piece | unit 8d in the indoor unit 100 of the air conditioner concerning Embodiment 1 of this invention. It is a figure which expands and shows the VI section of FIG. FIG. 5 is a cross-sectional view showing a part of a VII-VII cross section of FIG. 3; FIG. 5 is a cross-sectional view showing a part of a VIII-VIII cross section of FIG. 3; FIG. 4 is a cross-sectional view showing a part of a cross section taken along line IX-IX of FIG. 3; In the impeller unit 8d of the indoor unit 100 of the air conditioner according to Embodiment 1 of the present invention, the centers 8gma, 8gmb and 8gmc have respective cross sections of the first end 8ca, the second end 8cb and the middle part 8cc. It is a figure which shows the virtual state which piled up on the same plane so that center 8hma, 8hmb, and 8hmc may correspond and correspond. In the cross flow fan 8 of the indoor unit 100 of the air conditioner concerning Embodiment 1 of this invention, it is a graph which shows the relationship between rotational displacement angle ratio A of the wing | blade 8c, and a motor input ratio. It is a graph which shows the relationship of tmax / L and motor input ratio in the crossflow fan 8 of the indoor unit 100 of the air conditioner concerning Embodiment 1 of this invention. In the cross flow fan 8 which satisfy | fills the relationship of 0.045 <= tmax / L <= 0.080, it is a graph which shows the relationship of tmax / t2 and motor input ratio. In the cross-flow fan 8 of the indoor unit 100 of the air conditioner concerning Embodiment 1 of this invention, it is a graph which shows the relationship between P / (2xRt) and motor input ratio.

Embodiment 1
The indoor unit of the air conditioner according to Embodiment 1 of the present invention will be described. FIG. 1: is an external appearance perspective view which shows the structure of the indoor unit 100 of the air conditioner concerning this Embodiment. FIG. 2 is a side view showing the internal structure of the indoor unit 100 of the air conditioner according to the present embodiment. Although FIG. 1 and FIG. 2 illustrate the wall-mounted indoor unit 100 installed on the wall 11a of the room 11, which is a space to be air-conditioned, the indoor unit 100 may be another indoor type such as a ceiling-embedded type. It may be a machine. In addition, the room 11 is not necessarily limited to the room in the house, and may be an office, a warehouse, or the like.

As shown in FIG. 1 and FIG. 2, the indoor unit 100 has a casing 1 for housing internal devices. The casing 1 has a casing body 1a attached to the wall 11a, and a front panel 1b provided on the front surface of the casing body 1a and capable of opening and closing. A suction grill 2 is formed on the top surface portion 1c of the casing body 1a. A plurality of openings 2 a are formed in the suction grill 2 as suction ports through which indoor air is sucked into the indoor unit 100. The suction grille 2 may be formed not only on the top surface portion 1c of the casing main body 1a but also on the front panel 1b. Further, the shape of the suction grille 2 is not particularly limited.

At the lower part of the casing main body 1a, there is formed an air outlet 3 through which conditioned air is blown into the room. The air outlet 3 is provided with a vertical wind direction vane 4a that adjusts the wind direction of the conditioned air in the vertical direction, and a left and right wind direction vane 4b that adjusts the wind direction of the conditioned air in the horizontal direction. The up and down wind direction vanes 4a are disposed downstream of the left and right wind direction vanes 4b. Shaft portions provided at both ends of the up and down wind direction vanes 4a are rotatably supported by a pair of bearing portions provided in the casing main body 1a with the blowout port 3 interposed therebetween. The shaft portion provided on the upper portion of the left and right wind direction vanes 4b is rotatably supported by a bearing portion provided on an upper wall 9b described later.

An air passage extending from the opening 2 a of the suction grill 2 to the blowout port 3 is formed at a central portion inside the casing 1. The air passage is provided with a filter 5 and a heat exchanger 7 that transmits the heat or cold of the refrigerant to the air that has passed through the filter 5 to generate conditioned air. Further, the air flow path is provided with a cross flow fan 8 that generates a flow of air from the opening 2 a toward the air outlet 3.

The filter 5 is formed, for example, in a mesh shape, and removes dust and the like in the air sucked from the opening 2a. The filter 5 is disposed downstream of the suction grille 2 and upstream of the heat exchanger 7 in the air passage.

The heat exchanger 7 is a fin-and-tube type heat exchanger provided with a plurality of aluminum plate-like fins arranged in parallel and a heat transfer tube penetrating the plate-like fins. The heat exchanger 7 constitutes a refrigeration cycle together with a compressor, an outdoor heat exchanger, a throttling device, and the like. The compressor, the outdoor heat exchanger, and the expansion device are accommodated in an outdoor unit (not shown). The heat exchanger 7 functions as an evaporator or heat absorber to cool the air during the cooling operation, and functions as a condenser or radiator to heat the air during the heating operation. Although in FIG. 2 the heat exchanger 7 is shaped to surround the front side (left side in FIG. 2) and the back side (right side in FIG. 2) of the impeller 8a, heat exchange is performed. The shape of the vessel 7 is not particularly limited.

The cross flow fan 8 includes an impeller 8a disposed in an air passage, a motor 12 (not shown in FIGS. 1 and 2) for rotationally driving the impeller 8a, and a suction passage air passage E1 and a blowout side. It has a stabilizer 9 divided into an air passage E2, and a guide wall 10 for guiding the air blown out from the impeller 8a to the outlet air passage E2 to the air outlet 3. The impeller 8 a is disposed on the downstream side of the heat exchanger 7 in the air path and on the upstream side of the blowout port 3. As the impeller 8 a rotates, room air is sucked from the opening 2 a and conditioned air is blown out from the blowout port 3. The impeller 8a is formed of a thermoplastic resin such as AS resin. The details of the impeller 8a will be described later with reference to FIGS.

The stabilizer 9 is formed to project into the air passage inside the casing 1 from the front side of the casing body 1 a. At the tip of the stabilizer 9, a tongue 9a facing the impeller 8a is formed. The tongue 9a extends in a direction perpendicular to the paper surface of FIG. 2 along the rotation axis O of the impeller 8a. The lower surface of the stabilizer 9 constitutes an upper wall 9 b of the outlet 3. A drain pan 9 c for receiving the condensed water from the heat exchanger 7 is formed on the upper surface of the stabilizer 9.

The guide wall 10 constitutes a rear wall of the outlet side air passage E2. The guide wall 10 forms a spiral slope which is inclined from the impeller 8 a to the air outlet 3. The downstream side portion of the guide wall 10 faces the upper wall 9 b with the blowout port 3 interposed therebetween.

FIG. 3 is an external view showing the configuration of the impeller 8 a and the motor 12 in the indoor unit 100 of the air conditioner according to the present embodiment. In FIG. 3, the front view of the impeller 8a and the motor 12 and the side view of the impeller 8a are shown together. FIG. 4 is an external perspective view showing a configuration of an impeller unit 8 d in the indoor unit 100 of the air conditioner according to the present embodiment. FIG. 5 is a side view showing a configuration of an impeller unit 8 d in the indoor unit 100 of the air conditioner according to the present embodiment.

As shown in FIGS. 3 to 5, the impeller 8a has a configuration in which a plurality of impeller units 8d are connected in the direction of the rotation axis O by welding or the like. Each of the plurality of impeller units 8d has a plurality of wings 8c and a support plate 8b supporting one end of each of the plurality of wings 8c.

The plurality of wings 8 c are disposed at predetermined intervals on a circumference centered on the rotation axis O, and extend generally along the rotation axis O. Each of the plurality of wings 8 c has a first end 8 ca and a second end 8 cb as an end in a direction along the rotation axis O. The first end 8ca is supported by the outer periphery of one surface of the support plate 8b. That is, in the impeller unit 8d, each of the plurality of wings 8c protrudes from the outer peripheral portion of one surface of the support plate 8b in a direction substantially perpendicular to the surface. In the impeller unit 8d, the first end 8ca is an end of the root of the wing 8c, and the second end 8cb is an end of the tip of the wing 8c.

Further, each of the plurality of wings 8c has an intermediate portion 8cc located in the middle between the first end 8ca and the second end 8cb in the direction along the rotation axis O. Assuming that the distance between two adjacent support plates 8b, that is, the distance between the first end 8ca and the second end 8cb in the direction along the rotation axis O is P, the first end in the direction along the rotation axis O The distance between the portion 8ca and the middle portion 8cc is P / 2.

The support plate 8 b has a disk-like shape centered on the rotation axis O. As shown in FIGS. 7 to 9 described later, the radius of the support plate 8b is Rr. The support plate 8b located in the impeller 8a other than the both ends in the direction of the rotational axis O may have a ring shape with the central axis opened with the rotational axis O as the center.

One end of the impeller 8 a in the rotation axis O direction is connected to the motor 12 via the motor shaft 12 a. A fan boss 8e is provided on the support plate 8b located at the end. The fan boss 8 e is formed to project to the inside of the impeller 8 a along the rotation axis O. The fan boss 8e is fixed to the motor shaft 12a using a screw or the like.

At the other end of the impeller 8a in the direction of the rotation axis O, an end plate 8f having a disk shape centered on the rotation axis O is provided. The end plate 8f has the same radius as the support plate 8b. The end plate 8 f is provided with a fan shaft 8 fa extending along the rotation axis O to the outside of the impeller 8 a. The fan shaft 8 fa is rotatably supported by a bearing provided on the casing body 1 a.

When the motor 12 is energized, the driving force of the motor 12 is transmitted to the impeller 8a via the motor shaft 12a. Thereby, the impeller 8a rotates in the rotation direction RO centering on the rotation axis O. As the impeller 8 a rotates, room air is sucked from the opening 2 a of the suction grille 2, and conditioned air is blown out from the blowout port 3.

Next, the shape of the wing 8c will be described in more detail. 6 is an enlarged view of a portion VI of FIG. As shown in FIG. 6, the second end 8cb of the wing 8c is disposed forward of the first end 8ca by a rotational displacement angle θ2 in the rotational direction RO of the impeller 8a. Thereby, the wing | blade 8c inclines only angle (delta) in the circumferential direction with respect to the rotating shaft O (refer FIG. 3). That is, the wing 8c is a so-called skewed wing. The intermediate portion 8cc of the wing 8c is disposed forward of the first end 8ca by a rotational displacement angle θ1 (θ1 = θ2 / 2) in the rotational direction RO of the impeller 8a.

When the blade is not inclined with respect to the rotation axis, the timing of passing through the tongue portion that divides the suction side air passage and the discharge side air passage is simultaneous at each position in the blade rotation axis direction. On the other hand, in the present embodiment, since the wing 8c is inclined with respect to the rotation axis O, the timing of passing through the tongue 9a deviates at each position in the rotation axis O direction of the wing 8c. Therefore, in the present embodiment, the rotational noise of the cross flow fan 8 can be reduced.

Further, the wing 8c is an end on the inner peripheral side of the impeller single unit 8d as an end in the radial direction about the rotation axis O, and an outer periphery on the outer peripheral side of the impeller single unit 8d And the side end 8g. The pressure surface 8j which is the side surface of the wing 8c on the rotational direction RO side is curved in the rotational direction RO as it goes from the inner peripheral end 8h to the outer peripheral end 8g. Similarly, the negative pressure surface 8k which is the side surface of the wing 8c opposite to the rotational direction RO is curved in the rotational direction RO as it goes from the inner end 8h to the outer end 8g. Thus, the wing 8c is curved so that the pressure surface 8j side is concave and the suction surface 8k side is convex.

Here, in the cross section perpendicular to the rotation axis O, the center of the inner peripheral end 8h of the wing 8c is 8 hm, and the angle formed by the two line segments respectively connecting the center 8 hm of the two adjacent wings 8c and the rotation axis O Is the pitch angle (see FIG. 5). At this time, the pitch angle α1 between two given wings 8c is different from the pitch angle α2 between two other wings 8c (α1 ≠ α2). That is, the plurality of blades 8c are not equal pitch blades all having a uniform pitch angle, but are unequal pitch blades having at least two different pitch angles. Thereby, since the periodic pressure fluctuation when each wing 8c approaches the tongue 9a or the guide wall 10 is alleviated, it is possible to suppress the NZ sound which is the rotational sound of the peak nature, and the air conditioner having high noise reduction The indoor unit 100 is obtained.

7 is a cross-sectional view showing a part of a VII-VII cross section of FIG. FIG. 8 is a cross-sectional view showing a part of a VIII-VIII cross section of FIG. FIG. 9 is a cross-sectional view showing a part of a cross section taken along the line IX-IX of FIG. 7, 8 and 9 respectively show cross sections of the first end 8ca, the second end 8cb and the middle part 8cc of one wing 8c taken along a plane perpendicular to the rotation axis O. In order to prevent the drawings from being complicated, cross-sectional hatching of the first end 8ca, the second end 8cb, and the middle portion 8cc is omitted in FIGS.

In the description of FIGS. 7 to 9, in principle, the same reference numerals are used for the configuration and the dimension common to the first end 8ca, the second end 8cb and the middle portion 8cc. However, in order to distinguish the configuration or dimensions in each of the first end 8ca, the second end 8cb, and the middle portion 8cc, individual codes in which “a”, “b” and “c” are added to the common codes respectively May be used. In FIG. 7 to FIG. 9, individual reference numerals are shown in parentheses with some common reference numerals.

As shown in FIGS. 7 to 9, the cross-sectional area of the second end 8cb in a cross section perpendicular to the rotation axis O is smaller than the cross-sectional area of the first end 8ca in a cross section perpendicular to the rotation axis O. ing. The cross-sectional area of the intermediate portion 8cc in a cross section perpendicular to the rotation axis O is larger than the cross-sectional area of the second end 8cb and smaller than the cross-sectional area of the first end 8ca. That is, the cross-sectional area of the wing 8c in a cross section perpendicular to the rotation axis O gradually decreases from the first end 8ca to the second end 8cb. Accordingly, the wing 8c has a shape that is tapered in the direction of the rotation axis O generally from the first end 8ca to the second end 8cb.

The distance Rtb between the rotation axis O and the outer peripheral end 8gb at the second end 8cb is shorter than the distance Rta between the rotation axis O and the outer peripheral end 8ga at the first end 8ca (Rtb <Rta). The distance Rtc between the rotation axis O and the outer peripheral side end 8gc at the intermediate portion 8cc is longer than the distance Rtb and shorter than the distance Rta (Rtb <Rtc <Rta). That is, the distance between the rotation axis O and the outer peripheral side end 8g is gradually reduced from the first end 8ca to the second end 8cb. Here, a distance Rt between the rotation axis O and the outer peripheral side end 8g is defined as a radius of a circumscribed circle which is in contact with the outer peripheral side end 8g with the rotation axis O as a center in a cross section perpendicular to the rotation axis O.

The distance Rib between the rotation axis O and the inner end 8hb at the second end 8cb is longer than the distance Ria between the rotation axis O and the inner end 8ha at the first end 8ca. (Rib> Ria). The distance Ric between the rotation axis O and the inner peripheral end 8hc at the intermediate portion 8cc is shorter than the distance Rib and longer than the distance Ria (Rib> Ric> Ria). That is, the distance between the rotation axis O and the inner peripheral end 8h gradually increases from the first end 8ca to the second end 8cb. Here, the distance Ri between the rotation axis O and the inner peripheral end 8 h is defined as the radius of the inscribed circle in contact with the inner peripheral end 8 h with the rotation axis O as a center.

Here, the chord line Lo and the chord length L will be described. The chord line Lo is defined as a straight line in contact with both the contour of the inner peripheral end 8 h and the contour of the outer peripheral end 8 g in a cross section perpendicular to the rotation axis O. The chord length L is defined as the length of the wing 8 c in the direction along the chord line Lo. That is, the chord length L is a straight line perpendicular to the chord line Lo and in contact with the contour of the inner end 8h, and a straight line perpendicular to the chord line Lo and in contact with the contour of the outer end 8g Equal to the distance. The chord length Lb of the second end 8cb is shorter than the chord length La of the first end 8ca (Lb <La). The chord length Lc of the middle portion 8cc is longer than the chord length Lb of the second end 8cb and shorter than the chord length La of the first end 8ca (Lb <Lc <La). That is, the chord length L gradually reduces from the first end 8ca to the second end 8cb.

In each of the cross sections shown in FIGS. 7 to 9, the contour of the inner peripheral end 8h is constituted by an arc of approximately half a circumference around the center 8 hm. One end of the arc is connected to the inner peripheral end of the pressure surface 8j, and the other end of the arc is connected to the inner peripheral end of the negative pressure surface 8k. The thickness of the inner peripheral end 8h is t1. The outline of the outer peripheral side end portion 8g is configured by an arc of approximately half a circumference around a center 8gm. One end of the arc is connected to the outer peripheral end of the pressure surface 8j, and the other end of the arc is connected to the outer peripheral end of the negative pressure surface 8k. The thickness of the outer peripheral end 8g is t2. In each cross section, when the thickness t1 of the inner peripheral end 8h and the thickness t2 of the outer peripheral end 8g are compared, the thickness t1 is larger than the thickness t2 (t1> t2, t1a> t2a , T1b> t2b, t1c> t2c). Further, since the wing 8c has a tapered shape, the thickness t1 of the inner peripheral end 8h gradually decreases from the first end 8ca to the second end 8cb (t1a> t1c> t1b). Similarly, the thickness t2 of the outer peripheral side end 8g gradually decreases from the first end 8ca to the second end 8cb (t2a> t2c> t2b).

Here, the thickness t1 of the inner peripheral end 8h is the contour of the inner peripheral end 8h, the diameter of the inscribed circle in contact with the pressure surface 8j and the negative pressure surface 8k in a cross section perpendicular to the rotation axis O, It is defined. The thickness t2 of the outer peripheral end 8g is defined as the contour of the outer peripheral end 8g, the diameter of the inscribed circle in contact with the pressure surface 8j and the negative pressure surface 8k in a cross section perpendicular to the rotation axis O. The thickness of the other portion of the wing 8c is defined as the diameter of the inscribed circle in contact with the pressure surface 8j and the suction surface 8k in a cross section perpendicular to the rotation axis O.

In each of the cross sections shown in FIGS. 7 to 9, the wing 8c has the largest thickness portion TM where the thickness (that is, the diameter of the inscribed circle in contact with the pressure surface 8j and the suction surface 8k) becomes maximum. There is. The largest thick portion TM is located closer to the inner peripheral end 8 h than a straight line Lo 3 which passes through the middle point Lo 2 of the chord line Lo and is perpendicular to the chord line Lo. In addition, the largest thickness portion TM is located on the outer peripheral side than the inner peripheral end 8 h. In each cross section shown in FIGS. 7 to 9, the thickness of the wing 8c gradually decreases from the largest thick portion TM toward the inner circumferential end 8h, and from the largest thick portion TM to the outer circumferential end 8g. Gradually decrease towards. The thickness of the largest thickness part TMa at the first end 8ca is tmaxa, the thickness of the largest thickness part TMb at the second end 8cb is tmaxb, and the largest thickness part TMc at the middle part 8cc Has a wall thickness of tmaxc. Since the wing 8c has a tapered shape, the thickness of the largest thickness portion TM gradually decreases from the first end 8ca to the second end 8cb (tmaxa> tmaxc> tmaxb).

For example, at the second end 8cb, the thickness t1b of the inner end 8hb is 0.60 mm, the thickness t2b of the outer end 8gb is 0.50 mm, and the thickness of the maximum thickness portion TMb tmaxb is 0.62 mm.

In the cross section shown in FIG. 7, when the center of the inscribed circle in contact with the outer peripheral end 8ga, the pressure surface 8ja and the negative pressure surface 8ka is 8 gma, the distance between the center 8 gma and the rotation axis O is Rga. In the cross section shown in FIG. 8, when the center of the inscribed circle in contact with the outer peripheral end 8gb, the pressure surface 8jb and the negative pressure surface 8kb is 8gmb, the distance between the center 8gmb and the rotation axis O is Rgb. In the cross section shown in FIG. 9, when the center of the inscribed circle in contact with the outer peripheral end 8gc, the pressure surface 8jc and the negative pressure surface 8kc is 8gmc, the distance between the center 8gmc and the rotation axis O is Rgc. The distance Rga, the distance Rgb, and the distance Rgc are equal (Rga = Rgb = Rgc). The distance Rga, the distance Rgb, and the distance Rgc may be collectively referred to as a distance Rg (Rga = Rgb = Rgc = Rg).

In the cross section shown in FIG. 7, when the center of the inscribed circle in contact with the inner peripheral end 8ha, the pressure surface 8ja and the negative pressure surface 8ka is 8 hma, the distance between the center 8 hma and the rotation axis O is Rha. In the cross section shown in FIG. 8, when the center of the inscribed circle in contact with the inner peripheral end 8hb, the pressure surface 8jb and the negative pressure surface 8kb is 8 hmb, the distance between the center 8 hmb and the rotation axis O is Rhb. In the cross section shown in FIG. 9, when the center of the inscribed circle in contact with the inner peripheral end 8hc, the pressure surface 8jc and the negative pressure surface 8kc is 8 hmc, the distance between the center 8 hmc and the rotation axis O is Rhc. The distance Rha, the distance Rhb and the distance Rhc are equal (Rha = Rhb = Rhc). The distance Rha, the distance Rhb and the distance Rhc may be collectively referred to as a distance Rh (Rha = Rhb = Rhc = Rh). Further, the distance between the center 8hma and the center 8gma in the cross section shown in FIG. 7, the distance between the center 8hmb and the center 8gmb in the cross section shown in FIG. 8, and the distance between the center 8hmc and the center 8gmc in the cross section shown in FIG. Are equal.

In the cross section shown in FIG. 7, when the center of the inscribed circle in contact with the pressure surface 8ja and the suction surface 8ka at the thickest portion TMa is TMma, the distance between the center TMma and the rotation axis O is Rma. The distance Rma is longer than the distance Rha and shorter than the distance Rga (Rha <Rma <Rga). In the cross section shown in FIG. 8, when the center of the inscribed circle in contact with the pressure surface 8jb and the suction surface 8kb at the thickest portion TMb is TMmb, the distance between the center TMmb and the rotation axis O is Rmb. The distance Rmb is longer than the distance Rhb and shorter than the distance Rgb (Rhb <Rmb <Rgb). In the cross section shown in FIG. 9, when the center of the inscribed circle in contact with the pressure surface 8jc and the suction surface 8kc at the thickest portion TMc is TMmc, the distance between the center TMmc and the rotation axis O is Rmc. The distance Rmc is longer than the distance Rhc and shorter than the distance Rgc (Rhc <Rmc <Rgc). The distance Rma, the distance Rmb and the distance Rmc are equal (Rma = Rmb = Rmc). The distance Rma, the distance Rmb and the distance Rmc may be collectively referred to as a distance Rm (Rma = Rmb = Rmc = Rm). Further, the distance between the center 8hma and the center TMma in the cross section shown in FIG. 7, the distance between the center 8hmb and the center TMmb in the cross section shown in FIG. 8, the distance between the center 8hmc and the center TMmc in the cross section shown in FIG. Are equal. Furthermore, the distance between the center 8gma and the center TMma in the cross section shown in FIG. 7, the distance between the center 8gmb and the center TMmb in the cross section shown in FIG. 8, and the distance between the center 8gmc and the center TMmc in the cross section shown in FIG. Are equal.

A distance Rta between the rotation axis O and the outer peripheral end 8ga of the first end 8ca, a distance Rtb between the rotation axis O and the outer peripheral end 8gb of the second end 8cb, the rotation axis O with the first end 8ca The distance Ria with the inner peripheral end 8ha, the distance Rib between the rotation axis O and the inner peripheral end 8hb of the second end 8cb, and the first end 8ca with the second end in the direction along the rotational axis O The distance P with the end 8cb satisfies the following relationship.
(Rta-Rtb) / P = (Rib-Ria) / P

FIG. 10 shows cross sections of the first end 8ca, the second end 8cb, and the middle 8cc in the impeller unit 8d of the indoor unit 100 of the air conditioner according to the present embodiment, with centers 8gma, 8gmb and 8gmc. Is a virtual state of being superimposed on the same plane so that centers 8 hma, 8 hmb and 8 hmc coincide. 10 is a drawing, the cross section of the first end 8ca shown in FIG. 7, the cross section of the second end 8cb shown in FIG. 8 and the cross section of the intermediate part 8 cc shown in FIG. It is obtained by relative rotation and superposition. In FIG. 10, the centers TMma, TMmb and TMmc of the largest thick part TM in each cross section also coincide.

As shown in FIG. 10, the distance ΔLe between the contour of the cross section of the first end 8ca and the contour of the cross section of the second end 8cb is constant over the entire circumference of the wing 8c. Further, the distance ΔLeac between the contour of the cross section of the first end 8ca and the contour of the cross section of the intermediate portion 8cc is constant over the entire circumference of the wing 8c, and the contour of the cross section of the intermediate portion 8cc and the second The distance ΔLebc to the contour of the cross section of the end 8cb is constant over the entire circumference of the wing 8c. The distances ΔLeac and ΔLebc are both equal to half the distance ΔLe (ΔLeac = ΔLebc = ΔLe / 2).

The pressure surface 8j in each cross section has a first straight portion 8Lj adjacent to the inner peripheral end 8h. Further, the negative pressure surface 8k in each cross section has a second linear portion 8Lk adjacent to the inner peripheral end 8h.

Specifically, the pressure surface 8ja in the cross section shown in FIG. 7 has a first curve portion 8Cja formed of a curve in which the pressure surface 8ja side is concave and a first straight portion 8Lja formed of a straight line. ing. One end of the first curved portion 8Cja is connected to the pressure surface side end of the arc that constitutes the outline of the outer peripheral side end 8ga. The other end of the first curved portion 8Cja is connected to one end of the first straight portion 8Lja. The other end of the first straight portion 8Lja is connected to the pressure surface side end of an arc that constitutes the contour of the inner peripheral side end 8ha. The first curved portion 8Cja is a multiple arc curve formed of two or more arcs different in radius. The radius Rja1 of the arc on the outer peripheral end 8ga side is larger than the radius Rja2 of the arc on the inner peripheral end 8ha side.

The negative pressure surface 8ka has a second curved portion 8Cka which is formed of a curve which is convex on the negative pressure surface 8ka side, and a second straight portion 8Lka which is formed of a straight line. One end of the second curved portion 8Cka is connected to the negative pressure surface side end of an arc that constitutes the outline of the outer peripheral side end 8ga. The other end of the second curved portion 8Cka is connected to one end of the second straight portion 8Lka. The other end of the second straight portion 8Lka is connected to the negative pressure surface side end of an arc that constitutes the contour of the inner peripheral side end 8ha. The second straight portion 8Lka is parallel to the first straight portion 8Lja. The second curved portion 8Cka is a multiple arc curve formed of two or more arcs different in radius. The radius Rka1 of the arc on the outer peripheral end 8ga side is larger than the radius Rka2 of the arc on the inner peripheral end 8ha side.

The pressure surface 8jb in the cross section shown in FIG. 8 has a first curved portion 8Cjb formed of a curve which is concave on the pressure surface 8jb side, and a first straight portion 8Ljb formed of a straight line. One end of the first curved portion 8Cjb is connected to the pressure surface side end of an arc that constitutes the outline of the outer peripheral side end 8gb. The other end of the first curved portion 8Cjb is connected to one end of the first straight portion 8Ljb. The other end of the first straight portion 8Ljb is connected to the pressure surface side end of an arc that constitutes the contour of the inner peripheral side end 8hb. The first curved portion 8Cjb is a multiple arc curve formed of two or more arcs different in radius. The radius Rjb1 of the arc on the outer peripheral end 8gb side is larger than the radius Rjb2 of the arc on the inner peripheral end 8hb side.

The negative pressure surface 8 kb has a second curved portion 8 Ckb formed of a curve which is convex on the negative pressure surface 8 kb side, and a second straight portion 8 Lkb formed of a straight line. One end of the second curved portion 8Ckb is connected to the negative pressure surface side end of an arc that constitutes the outline of the outer peripheral side end 8gb. The other end of the second curved portion 8Ckb is connected to one end of the second straight portion 8Lkb. The other end of the second straight portion 8Lkb is connected to the negative pressure surface side end of an arc that constitutes the contour of the inner peripheral side end 8hb. The second straight portion 8Lkb is parallel to the first straight portion 8Ljb. The second curved portion 8Ckb is a multiple arc curve formed of two or more arcs different in radius. The radius Rkb1 of the arc on the outer peripheral end 8gb side is larger than the radius Rkb2 of the arc on the inner peripheral end 8hb side.

The pressure surface 8jc in the cross section shown in FIG. 9 has a first curved portion 8Cjc formed of a curve which is concave on the pressure surface 8jc side, and a first straight portion 8Ljc formed of a straight line. One end of the first curved portion 8Cjc is connected to the pressure surface side end of the arc that constitutes the outline of the outer peripheral side end 8gc. The other end of the first curved portion 8Cjc is connected to one end of the first straight portion 8Ljc. The other end of the first straight portion 8Ljc is connected to the pressure surface side end of an arc that constitutes the contour of the inner peripheral side end 8hc. The first curved portion 8Cjc is a multiple arc curve formed of two or more arcs different in radius. The radius Rjc1 of the arc on the outer peripheral end 8gc side is larger than the radius Rjc2 of the arc on the inner peripheral end 8hc side.

The negative pressure surface 8kc has a second curved portion 8Ckc formed of a curve which is convex on the negative pressure surface 8kc side, and a second straight portion 8Lkc formed of a straight line. One end of the second curved portion 8Ckc is connected to the negative pressure surface side end of an arc that constitutes the outline of the outer peripheral side end 8gc. The other end of the second curved portion 8Ckc is connected to one end of the second straight portion 8Lkc. The other end of the second straight portion 8Lkc is connected to the negative pressure surface side end of an arc that constitutes the contour of the inner peripheral side end 8hc. The second straight portion 8Lkc is parallel to the first straight portion 8Ljc. The second curved portion 8Ckc is a multiple arc curve formed of two or more arcs different in radius. The radius Rkc1 of the arc on the outer peripheral end 8gc side is larger than the radius Rkc2 of the arc on the inner peripheral end 8hc side.

Since the second straight portions 8Lka, 8Lkb and 8Lkc are parallel to the first straight portions 8Lja, 8Ljb and 8Ljc, respectively, a flat plate portion is formed on the inner peripheral end 8h side of the wing 8c. There is. The flat plate portion has a constant thickness in a cross section perpendicular to the rotation axis O.

In each of the cross sections shown in FIGS. 7 to 9, the wing 8c has a maximum warpage portion having the maximum warpage heights hsa, hsb and hsc on the inner peripheral side end 8h side of the straight line Lo3. Here, the maximum warpage height is defined as the maximum value of the distance from the chord line Lo to the suction surface 8k. The distance Ls from the inner circumferential end 8h to the maximum warpage in the direction along the chord line Lo is shorter than half the chord length L (Ls <L / 2).

FIG. 11 is a graph showing the relationship between the rotational displacement angle ratio A of the wing 8c and the motor input ratio in the cross flow fan 8 of the indoor unit 100 of the air conditioner according to the present embodiment. The horizontal axis of the graph represents the rotational displacement angle ratio A [deg / mm] of the wing 8c, and the vertical axis represents the motor input ratio (%) of the cross flow fan 8. Here, the rotational displacement angle ratio A is represented by θ 2 / P [deg / mm]. θ2 [deg] is a rotational displacement angle with respect to the first end 8ca of the second end 8cb around the rotation axis O (see FIG. 6). P [mm] is the distance between the first end 8 ca and the second end 8 cb in the direction along the rotation axis O (see FIG. 3).

As shown in FIG. 11, when the rotational displacement angle ratio A of the wing 8 c satisfies the relationship of 0.02 [deg / mm] ≦ A ≦ 0.05 [deg / mm], the motor is compared with the other cases. It can be seen that the input ratio can be reduced.

FIG. 12 is a graph showing the relationship between tmax / L and the motor input ratio in the cross flow fan 8 of the indoor unit 100 of the air conditioner according to the present embodiment. The horizontal axis of the graph represents tmax / L, and the vertical axis represents the motor input ratio (%) of the cross flow fan 8. Here, tmax [mm] is the thickness of the largest thickness portion TM of the wing 8c in a cross section perpendicular to the rotation axis O (see FIGS. 7 to 9). L [mm] is the chord length of the wing 8c in the same cross section (see FIGS. 7 to 9).

As shown in FIG. 12, it can be seen that the motor input ratio can be reduced when tmax / L satisfies the relationship 0.045 ≦ tmax / L ≦ 0.080. However, even when tmax / L satisfies the relationship 0.045 ≦ tmax / L ≦ 0.080, a high reduction effect of the motor input ratio can be obtained (a point represented by a square in the graph), and the motor There are cases where a high reduction effect of the input ratio can not be obtained (a point represented by a circle in the graph).

FIG. 13 is a graph showing the relation between tmax / t2 and the motor input ratio in the cross flow fan 8 satisfying the relation of 0.045 ≦ tmax / L ≦ 0.080. The horizontal axis of the graph represents tmax / t 2, and the vertical axis represents the motor input ratio (%) of the cross flow fan 8. Here, tmax [mm] is the thickness of the largest thickness portion TM of the wing 8c in a cross section perpendicular to the rotation axis O (see FIGS. 7 to 9). t2 [mm] is the thickness of the outer peripheral side end 8g of the wing 8c in the same cross section (see FIGS. 7 to 9).

As shown in FIG. 13, it can be seen that when tmax / t2 satisfies the relationship of 1.1 ≦ tmax / t2 ≦ 2.0, the motor input ratio can be reduced compared to the other cases. That is, according to FIGS. 12 and 13, tmax / L satisfies the relation 0.045 ≦ tmax / L ≦ 0.080, and the relation tmax / t2 satisfies 1.1 ≦ tmax / t2 ≦ 2.0. In the case where the above condition is satisfied, it is understood that a high reduction effect of the motor input ratio can be obtained. The above relationship is preferably satisfied in both the cross section of the first end 8ca and the cross section of the second end 8cb.

FIG. 14 is a graph showing the relationship between P / (2 × Rt) and motor input ratio in the cross flow fan 8 of the indoor unit 100 of the air conditioner according to the present embodiment. The horizontal axis of the graph represents P / (2 × Rt), and the vertical axis represents the motor input ratio (%) of the cross flow fan 8. Here, P [mm] is the distance between the first end 8 ca and the second end 8 cb in the direction along the rotation axis O (see FIG. 3). Rt [mm] is a distance between the rotation axis O and the outer peripheral end 8g in a cross section perpendicular to the rotation axis O (see FIGS. 7 to 9). As described above, since the distance Rt is defined as the radius of the circumscribed circle in contact with the outer peripheral end 8g around the rotation axis O in a cross section perpendicular to the rotation axis O, (2 × Rt) is the rotation axis O It is equal to the diameter of the circumscribed circle in contact with the outer peripheral end 8g about the rotation axis O in the vertical cross section.

As shown in FIG. 14, when P / (2 × Rt) satisfies the relationship of 0.45 ≦ P / (2 × Rt) ≦ 0.80, the motor input ratio can be reduced compared to the other cases. I understand. The above relationship is preferably satisfied in both the cross section of the first end 8ca and the cross section of the second end 8cb.

As described above, the indoor unit 100 of the air conditioner according to the present embodiment includes the casing 1 in which the opening 2 a and the outlet 3 are formed, and the cross flow fan 8 housed in the casing 1. There is. The cross flow fan 8 includes an impeller 8a disposed in an air passage formed in the casing 1, a stabilizer 9 dividing the air passage into a suction side air passage E1 and an outlet side air passage E2, and an impeller 8a. And a guide wall 10 for guiding the air blown out to the outlet side air path E2 to the outlet 3. The impellers 8a are respectively disposed on a circumference centered on the rotation axis O of the impeller 8a, and have a plurality of first ends 8ca and second ends 8cb as ends in a direction along the rotation axis O. It has a wing 8c and a support plate 8b for supporting the first end 8ca of each of the wings 8c. The second end 8cb is disposed forward of the first end 8ca in the rotational direction RO of the impeller 8a. Each of the plurality of wings 8 c has an inner peripheral end 8 h and an outer peripheral end 8 g as radial ends centered on the rotation axis O. The cross-sectional area of the second end 8cb in a cross section perpendicular to the rotation axis O is smaller than the cross-sectional area of the first end 8ca in a cross section perpendicular to the rotation axis O. The distance Rtb between the rotation axis O and the outer peripheral end 8g at the second end 8cb is shorter than the distance Rta between the rotation axis O and the outer peripheral end 8g at the first end 8ca. The distance Rib between the rotation axis O and the inner end 8h at the second end 8cb is longer than the distance Ria between the rotation axis O and the inner end 8h at the first end 8ca. . In a cross section perpendicular to the rotation axis O, the thickness t1 of the inner end 8h is larger than the thickness t2 of the outer end 8g. In a cross section perpendicular to the rotation axis O, each of the plurality of wings 8c passes the middle point Lo2 of the chord line Lo of each of the plurality of wings 8c, and the inner circumferential end than the straight line Lo3 perpendicular to the chord line Lo On the 8h side, there is the largest thickness part TM where the thickness is the largest. Here, the opening 2a is an example of a suction port.

A minimum gap between the outer peripheral end 8g of the wing 8c and the tongue 9a of the stabilizer 9 is a fan gap G1, and a minimum clearance between the outer peripheral end 8g of the wing 8c and the guide wall 10 is the fan gap G2. (See Figure 2). In the present embodiment, the fan gaps G1 and G2 both gradually increase from the first end 8ca of the wing 8c toward the second end 8cb. At the first end 8ca, since the fan gaps G1 and G2 are relatively narrow, the flow of air changes rapidly from the suction side air passage E1 to the blowout side air passage E2. However, in the present embodiment, since the first end 8ca is relatively thick compared to the second end 8cb, peeling is less likely to occur even if an angle change occurs due to a change in air flow. . On the other hand, at the second end 8cb, the fan gaps G1 and G2 become relatively wide. Therefore, although the second end 8cb is relatively thin, the fluctuation of the flow of air from the suction side air passage E1 to the blowout side air passage E2 is relatively small at the second end 8cb, Peeling is less likely to occur. Therefore, according to the present embodiment, since generation of a vortex due to separation can be suppressed, the effective passage area when air passes between adjacent wings 8c can be expanded. Efficiency can be improved.

The inter-blade distance between adjacent wings 8c is smaller on the thick first end 8ca side than on the thin second end 8cb side. The chord length La of the first end 8ca is longer than the chord length Lb of the second end 8cb. Thereby, the inter-blade distance gradually increases from the first end 8ca to the second end 8cb. In addition, the inter-blade passing wind speed gradually decreases from the first end 8ca to the second end 8cb. Thus, a pressure gradient can be generated in the direction from the first end 8ca to the second end 8cb. Therefore, according to the present embodiment, even if the flow of air becomes unstable on the side of the first end 8ca, the flow is suppressed by the pressure gradient, so that the flow can be stabilized.

On the suction side of the impeller 8a, air flows from the outer peripheral end 8g of the wing 8c toward the inner peripheral end 8h. In the present embodiment, since the largest thick portion TM is formed on the inner peripheral side of the wing 8c, the distance between the wings is small even if the flow of air tends to separate from the wing surface on the outer peripheral side of the wing 8c. Peeling can be suppressed by the largest thick part TM of the wing 8c. On the other hand, on the outlet side of the impeller 8a, air flows from the inner peripheral end 8h of the wing 8c toward the outer peripheral end 8g. At the outlet side of the impeller 8a, the inflow angle of air to the wing 8c is more likely to change than the inlet side of the impeller 8a due to the fluctuation of the flow. In the present embodiment, since the thickness t1 of the inner peripheral end 8h which is the front edge is larger than the thickness t2 of the outer peripheral end 8g, separation is caused even if the inflow angle of air changes. It can be suppressed to occur. Therefore, according to the present embodiment, the generation of a vortex due to separation can be suppressed, so the effective passage area between adjacent wings 8c can be expanded, and the efficiency of the cross flow fan 8 can be improved. Can.

Further, in the present embodiment, the inner peripheral end 8 h of the wing 8 c is relatively thick, and the wing 8 c is inclined with respect to the rotation axis O. For this reason, even if the flow is likely to be separated in a partial region of the blade surface due to the angular difference between the air flow and the blade surface of the blade 8c on the outlet side of the impeller 8a, the flow is deviated from the flow timing. Peeling is suppressed by mixing with another flow flowing into the partial region. Therefore, the rotational noise of the cross flow fan 8 can be reduced. Moreover, since the effective passage area between the adjacent wing | blades 8c can be expanded, the efficiency of the crossflow fan 8 can be improved.

Furthermore, since the wing 8c is inclined with respect to the rotation axis O in the present embodiment, even if separation of the flow occurs at the outer peripheral end 8g after passing through the tongue 9a on the suction side of the impeller 8a, A part of the vortex generated by the separation moves to the downstream side, that is, the first end 8ca side according to the inclination of the wing 8c. Thereby, the shape of the vortex can be flattened along the wing surface of the wing 8c, and therefore, the thickness of the vortex on the wing surface can be reduced. Therefore, the effective passage area between the adjacent wings 8c can be expanded, so the efficiency of the cross flow fan 8 can be improved.

As described above, according to the present embodiment, the efficiency of the cross flow fan 8 can be improved, and the rotational noise of the cross flow fan 8 can be reduced. Therefore, the indoor unit 100 of the air conditioner excellent in energy saving performance and high in quality can be obtained.

In the indoor unit 100 of the air conditioner according to the present embodiment, the cross section perpendicular to the rotation axis O at the first end 8ca is taken as the first cross section of each of the plurality of wings 8c, and the rotation at the second end 8cb A cross section perpendicular to the axis O is taken as a second cross section of each of the plurality of wings 8c. In the first cross section, the inscribed circle in contact with the outer peripheral end 8ga, the pressure surface 8ja and the negative pressure surface 8ka is a first inscribed circle, and in the second cross section, the outer peripheral end 8gb, the pressure surface 8jb and the negative pressure surface 8kb Let the inscribed circle in contact be the second inscribed circle. In the first cross section, an inscribed circle in contact with the inner peripheral end 8ha, the pressure surface 8ja and the negative pressure surface 8ka is a third inscribed circle, and in the second cross section, the inner peripheral end 8hb, the pressure surface 8jb and the negative pressure surface Let the inscribed circle in contact with 8 kb be the fourth inscribed circle. At this time, the distance Rga between the rotation axis O and the center 8gma of the first inscribed circle and the distance Rgb between the rotation axis O and the center 8gmb of the second inscribed circle are equal. Further, the distance Rha between the rotation axis O and the center 8hma of the third inscribed circle and the distance Rhb between the rotation axis O and the center 8hmb of the fourth inscribed circle are equal.

According to this configuration, since there is no large distortion in the shape of the wing 8c, the difference in flow between the cross sections perpendicular to the rotation axis O is reduced. Therefore, partial peeling or disturbance is unlikely to occur at each position in the direction of the rotation axis O of the wing 8c, so the efficiency of the cross flow fan 8 can be improved.

In the cross flow fan described in Patent Document 1, the cross-sectional center of the blade is displaced radially outward of the impeller from the root toward the tip. In such a cross flow fan, the centrifugal force applied to the tip of the wing is greater than the centrifugal force applied to the base of the wing. As a result, deformation of the blade is apt to occur due to load fluctuation, so that the noise of the cross flow fan may increase and the efficiency may decrease. On the other hand, in the present embodiment, the distance between the rotation axis O and the center 8 gm of the outer peripheral end 8 g and the distance between the rotation axis O and the center 8 hm of the inner peripheral end 8 h are all first ends. It is constant between the portion 8ca and the second end 8cb. Therefore, since deformation of the wing 8c due to load fluctuation can be suppressed, noise reduction and high efficiency of the cross flow fan 8 can be realized.

Further, in the indoor unit 100 of the air conditioner according to the present embodiment, the inscribed circle in contact with the pressure surface 8ja and the negative pressure surface 8ka at the largest thick portion TMa of the first cross section is taken as a fifth inscribed circle. Let the inscribed circle in contact with the pressure surface 8 j b and the suction surface 8 kb at the largest thick portion TMb be a sixth inscribed circle. At this time, the distance Rma between the rotation axis O and the center TMma of the fifth inscribed circle and the distance Rmb between the rotation axis O and the center TMmb of the sixth inscribed circle are equal.

According to this configuration, when connecting the plurality of single impellers 8d in the direction of the rotation axis O, twisting of the wings 8c is less likely to occur, so the assembling workability of the impeller 8a is improved.

Further, in the indoor unit 100 of the air conditioner according to the present embodiment, the center 8gma of the first inscribed circle and the center 8gmb of the second inscribed circle coincide, and the center 8hma of the third inscribed circle and the third When the first cross section and the second cross section are superimposed on the same plane so that the center 8 hmb of the inscribed circle 4 coincides, the distance ΔLe between the contour of the first cross section and the contour of the second cross section is It is constant all around each of the multiple wings.

Further, in the indoor unit 100 of the air conditioner according to the present embodiment, a distance between the rotation axis O and the outer peripheral end 8ga at the first end 8ca is Rta, and the rotation axis O and the second end 8cb The distance between the rotation axis O and the inner peripheral end 8ha at the first end 8ca is Ria. The inner circumference at the rotation axis O and the second end 8cb is Rtb. Assuming that the distance to the side end 8 hb is Rib, and the distance between the first end 8 ca and the second end 8 cb in the direction along the rotation axis O is P,
(Rta-Rtb) / P = (Rib-Ria) / P
Relationship is satisfied.

According to these configurations, the distance ΔLe can be made constant over the entire circumference of the wing 8c, and the rate of change of the distance between the rotation axis O and the outer peripheral end 8g in the rotation axis O direction, and the rotation axis O And the rate of change in the direction of the rotation axis O of the distance between the inner circumferential end 8 h and the inner circumferential end 8 h can be made constant. Therefore, the flow does not become unstable at each position in the direction of the rotation axis O of the wing 8c, and separation or disturbance does not easily occur, so that the efficiency of the cross flow fan 8 can be improved. Thereby, the indoor unit 100 of the air conditioner excellent in energy saving property is obtained.

Further, in the indoor unit 100 of the air conditioner according to the present embodiment, the rotational displacement angle with respect to the first end 8 ca of the second end 8 cb about the rotational axis O is θ 2 [deg], and When the distance between the first end 8ca and the second end 8cb in the direction along is P [mm],
0.02 [deg / mm] ≦ θ2 / P ≦ 0.05 [deg / mm]
Relationship is satisfied.

If θ 2 / P is too small, the effect as a skewed wing will be small. On the other hand, when θ2 / P is too large, in each of the wings 8c, the flow from the second end 8cb located forward in the rotational direction toward the first end 8ca located aft, along the front edge of the wing 8c Will occur. As a result, the flow is concentrated on the side of the first end 8ca, and the wind speed distribution is formed in the direction along the rotation axis O, so that the noise is aggravated and separation occurs.

If θ 2 / P satisfies the above relationship, the blow-off direction is substantially orthogonal to the rotation axis O. For this reason, even if load fluctuation occurs, it becomes difficult to form a wind speed distribution such that the wind speed is locally slowed at the end in the direction of the rotation axis O in the outlet 3 of the indoor unit 100. Therefore, since the fluctuation of the air flow characteristic due to the load fluctuation can be suppressed, the noise of the cross flow fan 8 can be reduced and the efficiency of the cross flow fan 8 can be improved. Therefore, the indoor unit 100 of the air conditioner having high quality and excellent energy saving can be obtained.

Further, in the indoor unit 100 of the air conditioner according to the present embodiment, in the cross section perpendicular to the rotation axis O, the chord length of each of the plurality of wings 8c is L, and the thickness of the outer peripheral end 8g is t2. When the thickness of the largest thickness portion TM is tmax,
0.045 ≦ tmax / L ≦ 0.080 and 1.1 ≦ tmax / t2 ≦ 2.0
Relationship is satisfied.

In the thin-walled blade 8c satisfying the relationship 0.045 ≦ tmax / L ≦ 0.080, when tmax / t2 is smaller than 1.1, the distance from the outer peripheral end 8g to the maximum thickness portion TM is The change in the distance between wings becomes smaller between the two. As a result, once exfoliation occurs in the air flow, it becomes difficult to reattach. On the other hand, when tmax / t2 is larger than 2.0, the change in the inter-blade distance becomes large from the outer peripheral end 8g to the maximum thickness part TM. As a result, the width of the flow passage between the blades at the thickest portion TM becomes narrow, and the friction loss increases. In the thin-walled blade 8c satisfying the relation 0.045 ≦ tmax / L ≦ 0.080, if tmax / t2 satisfies the above relation, friction loss can be reduced while suppressing separation, so cross flow The efficiency of the fan 8 can be improved. Therefore, the indoor unit 100 of the air conditioner excellent in energy saving property is obtained.

Further, in the indoor unit 100 of the air conditioner according to the present embodiment, in the cross section perpendicular to the rotation axis O, the pressure surface 8j of each of the plurality of wings 8c has a first For example, a first curve portion 8Cja, 8Cjb or 8Cjc) and a first straight portion connected at one end to the first curve portion and the other end to the inner end 8h (for example, the first straight portion 8Lja, 8Ljb) Or 8Ljc). In the cross section perpendicular to the rotation axis O, each negative pressure surface 8k of the plurality of blades 8c has a second curved portion (for example, the second curved portion 8Cka, 8Ckb or 8Ckc) in which the negative pressure surface 8k side is convex, And a second straight portion (for example, a second straight portion 8Lka, 8Lkb or 8Lkc) connected to the two curve portions and having the other end connected to the inner circumferential end 8h.

According to this configuration, on the suction side of the impeller 8a, the flow which is likely to be separated in the upstream first curve portion or the second curve portion is reattached on the downstream first straight portion or the second straight portion. be able to. Therefore, the fluid abnormal sound due to the local peeling can be suppressed. Thereby, the indoor unit of the high quality air conditioner in which the fluid abnormal noise was suppressed is obtained.

In the indoor unit 100 of the air conditioner according to the present embodiment, the distance between the rotation axis O and the outer peripheral end 8g at the first end 8ca is Rta, and the first in the direction along the rotation axis O When the distance between the end 8ca and the second end 8cb is P,
0.45 ≦ P / (2 × Rta) ≦ 0.80
Relationship is satisfied.

According to this configuration, since the support plate 8b is disposed at an appropriate interval, even if separation occurs at the second end 8cb of the wing 8c on the suction side of the impeller 8a, the flow is unstable due to the support plate 8b Can be suppressed. As a result, even if dust accumulates on the filter 5, the air flow is unlikely to stall and a cross flow fan 8 with high efficiency at low load can be obtained.

Further, if the distance between the support plates 8b is too wide in the impeller 8a having the thin wing 8c, the wing 8c is deformed when assembling the impeller 8a, and the efficiency of the cross flow fan 8 is lowered. There is a case. On the other hand, according to the above configuration, it is possible to prevent the change of the air blowing characteristic due to the deformation of the wing 8c, so that the indoor unit 100 of the high quality air conditioner can be obtained.

Further, in the indoor unit 100 of the air conditioner according to the present embodiment, in the cross section perpendicular to the rotation axis O, the pressure surfaces 8 j of the plurality of wings 8 c have a plurality of arcs with different radii. Furthermore, in a cross section perpendicular to the rotation axis O, each suction surface 8k of the plurality of wings 8c has a plurality of arcs with different radii.

Since the suction surface 8k has a plurality of arcs with different radii, even if the flow starts to separate on a part of the suction surface 8k, the flow can be reattached in another arc portion with a different radius, so cross flow The loss of the fan 8 can be reduced. In addition, since the pressure surface 8j has a plurality of arcs with different radii, the pressure can be gradually increased on the pressure surface 8j side, so that the friction loss can be reduced. As a result, the wing 8 c can be thinned while the efficiency of the cross flow fan 8 can be enhanced, so that the impeller 8 a can be reduced in weight. Therefore, the indoor unit 100 of the air conditioner excellent in energy saving property and lightweight can be obtained.

Reference Signs List 1 casing, 1a casing body, 1b front panel, 1c top panel, 2 suction grille, 2a opening, 3 outlet, 4a vertical wind direction vane, 4b left and right wind direction vane, 5 filter, 7 heat exchanger, 8 cross flow fan, 8a Impeller, 8b support plate, 8c wing, 8ca first end, 8cb second end, 8cc middle part, 8d impeller alone, 8e fan boss, 8f end plate, 8fa fan shaft, 8g outer peripheral end, 8gm Center, 8h inner circumferential end, 8hm center, 8j pressure surface, 8k negative pressure surface, 8Lj first straight section, 8Lk second straight section, 9 stabilizer, 9a tongue, 9b top wall, 9c drain pan, 10 guide wall, 10 guide wall 11 rooms, 11a wall, 12 motors, 12a motor shaft, 100 indoor units, Rotational displacement angle ratio, E1 suction side air path, E2 outlet side air path, G1, G2 fan gap, L chord length, Lo chord line, Lo2 middle point, Lo3 straight line, O rotation axis, P, Rg, Rh, Ri, Rm, Rt distance, RO rotation direction, t1, t2, tmax thickness, TM maximum thickness part, TMm center, ΔLe, ΔLeac, ΔLebc distance, α1, α2 pitch angle, δ angle, θ1, θ2 rotational displacement angle .

Claims

A casing having an inlet and an outlet formed therein;
An indoor unit of an air conditioner comprising: a cross flow fan housed in the casing;
The cross flow fan is
An impeller disposed in an air passage formed in the casing;
A stabilizer that divides the air passage into a suction side air passage and a discharge side air passage;
A guide wall for guiding the air blown out from the impeller to the outlet side air path to the outlet;
And have
The impeller is
A plurality of wings respectively disposed on a circumference centered on the rotation axis of the impeller, and having a first end and a second end as ends in a direction along the rotation axis;
A support plate supporting the first end of each of the plurality of wings;
And have
The second end is disposed forward of the first end in the rotational direction of the impeller,
Each of the plurality of wings has an inner peripheral end and an outer peripheral end as radial ends centered on the rotation axis,
The cross-sectional area of the second end in a cross section perpendicular to the rotation axis is smaller than the cross-sectional area of the first end in a cross section perpendicular to the rotation axis,
The distance between the rotation axis and the outer peripheral end at the second end is shorter than the distance between the rotation axis and the outer peripheral end at the first end,
The distance between the rotation axis and the inner circumferential end at the second end is longer than the distance between the rotation axis and the inner circumferential end at the first end,
In the cross section perpendicular to the rotation axis, the thickness of the inner peripheral end is larger than the thickness of the outer peripheral end,
In a cross section perpendicular to the rotation axis, each of the plurality of wings passes through a midpoint of a chord line of each of the plurality of wings and is closer to the inner circumferential end than a straight line perpendicular to the chord line. , The indoor unit of the air conditioner that has the largest thickness part where the thickness is the largest.
A cross section perpendicular to the rotation axis at the first end is taken as a first cross section of each of the plurality of wings,
A cross section perpendicular to the rotation axis at the second end is a second cross section of each of the plurality of wings,
In the first cross section, an inscribed circle in contact with the outer peripheral side end, the pressure surface of each of the plurality of wings, and the negative pressure surface of each of the plurality of wings is a first inscribed circle,
In the second cross section, an inscribed circle in contact with the outer peripheral end, the pressure surface and the negative pressure surface is taken as a second inscribed circle,
In the first cross section, an inscribed circle in contact with the inner peripheral end portion, the pressure surface, and the suction surface is a third inscribed circle,
In the second cross section, when an inscribed circle in contact with the inner peripheral end portion, the pressure surface and the negative pressure surface is a fourth inscribed circle,
The distance between the rotation axis and the center of the first inscribed circle is equal to the distance between the rotation axis and the center of the second inscribed circle,
The indoor unit of the air conditioner according to claim 1, wherein the distance between the rotation axis and the center of the third inscribed circle and the distance between the rotation axis and the center of the fourth inscribed circle are equal.
Let an inscribed circle in contact with the pressure surface and the negative pressure surface at the maximum thickness portion of the first cross section be a fifth inscribed circle,
When an inscribed circle in contact with the pressure surface and the negative pressure surface in the largest thickness portion of the second cross section is a sixth inscribed circle,
The indoor unit of the air conditioner according to claim 2, wherein the distance between the rotation axis and the center of the fifth inscribed circle and the distance between the rotation axis and the center of the sixth inscribed circle are equal.
The first cross section so that the center of the first inscribed circle coincides with the center of the second inscribed circle, and the center of the third inscribed circle coincides with the center of the fourth inscribed circle And when the second cross section is superimposed on the same plane,
The indoor unit of the air conditioner according to claim 2 or 3, wherein a distance between an outline of the first cross section and an outline of the second cross section is constant all around each of the plurality of wings.
The distance between the rotation axis and the outer peripheral end at the first end is Rta,
Let the distance between the rotation axis and the outer peripheral end at the second end be Rtb,
The distance between the rotation axis and the inner peripheral end at the first end is Ria,
The distance between the rotation axis and the inner circumferential end at the second end is taken as Rib,
When a distance between the first end and the second end in a direction along the rotation axis is P,
(Rta-Rtb) / P = (Rib-Ria) / P
The indoor unit of the air conditioner according to any one of claims 1 to 4, wherein the following relationship is satisfied.
The rotational displacement angle of the second end with respect to the first end centering on the rotation axis is θ 2 [deg],
When the distance between the first end and the second end in the direction along the rotation axis is P [mm],
0.02 [deg / mm] ≦ θ2 / P ≦ 0.05 [deg / mm]
The indoor unit of the air conditioner according to any one of claims 1 to 5, wherein the following relationship is satisfied.
In a cross section perpendicular to the rotation axis, when a chord length of each of the plurality of wings is L, a thickness of the outer peripheral end is t2, and a thickness of the largest thickness portion is tmax,
0.045 ≦ tmax / L ≦ 0.080 and 1.1 ≦ tmax / t2 ≦ 2.0
The indoor unit of the air conditioner according to any one of claims 1 to 6, wherein the following relationship is satisfied.
In a cross section perpendicular to the rotation axis, the pressure surface of each of the plurality of blades has a first curve portion in which the pressure surface side is concave, one end is connected to the first curve portion, and the other end is the inner circumferential side And a first straight portion connected to the end portion,
In a cross section perpendicular to the rotation axis, each negative pressure surface of the plurality of blades has a second curved portion whose convex surface side is convex, one end is connected to the second curved portion, and the other end is the inner peripheral side The indoor unit of the air conditioner according to any one of claims 1 to 7, further comprising: a second straight portion connected to the end.
The distance between the rotation axis and the outer peripheral end at the first end is Rta,
When a distance between the first end and the second end in a direction along the rotation axis is P,
0.45 ≦ P / (2 × Rta) ≦ 0.80
The indoor unit of the air conditioner according to any one of claims 1 to 8, wherein the following relationship is satisfied.
In a cross section perpendicular to the rotation axis, each pressure surface of the plurality of wings has a plurality of arcs of different radii,
The air conditioner according to any one of claims 1 to 9, wherein each suction surface of the plurality of blades has a plurality of arcs with different radii in a cross section perpendicular to the rotation axis. Indoor unit.