Fan and air conditioner

Abstract

To provide a fan capable of suppressing generation of a vortex flow originating from a boundary between a scroll part and a non-continuous part.SOLUTION: A peripheral wall (43) has a scroll part (51, 52) that forms a scroll-shaped first inner surface (51a, 52a), and a non-continuous part (53) that bends radially inward with respect to the scroll part (51, 52) and forms a second inner surface (53a) that is not smoothly continuous with the first inner surface (51a, 52a). A porous part (60) is provided in the peripheral wall (43) within a range from the boundary between the scroll part (51, 52) and the non-continuous part (53) to a blowout port (45) of an air passage (46).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a fan and an air conditioning device. [Background technology]

[0002] Fans with impellers have been known for some time. Patent Document 1 discloses a sirocco fan. The sirocco fan has an impeller and a casing that surrounds the impeller. The inner surface of the peripheral wall of the casing is scroll-shaped. When the impeller rotates, air is drawn in through an intake port on the axial side of the casing. This air passes through an air passage between the casing and the impeller and is blown out from an outlet at the tip of the discharge section of the casing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-14021 Summary of the Invention [Problem to be solved by the invention]

[0004] As described in Patent Document 1, in a fan in which a casing surrounds an impeller, it is conceivable to adopt a structure in which a portion of the casing is cut. Specifically, for example, by making a portion of the peripheral wall of the casing flat, the circumferential length of the casing can be shortened. As a result, this fan can be housed compactly in an air conditioning casing such as an air conditioner. This allows the air conditioner to be made more compact.

[0005] However, when such a cut structure is adopted in the peripheral wall of the fan, the inner surface of the scroll section and the cut section (discontinuous section) are no longer smoothly connected, which causes vortices to form in the air passage starting from the boundary between the scroll section and the discontinuous section, resulting in increased noise.

[0006] The present disclosure provides a fan that can suppress the generation of vortex flows originating from the boundary between the scroll portion and the discontinuous portion. [Means for solving the problem]

[0007] The fan of the first aspect includes an impeller (33) and a casing (40) having a peripheral wall (43) surrounding the impeller (33) and forming an air passage (46) between the impeller (33) and the peripheral wall (43). The peripheral wall (43) has scroll portions (51, 52) forming scroll-shaped first inner surfaces (51 a, 52 a), and a discontinuous portion (53) bending radially inward relative to the scroll portions (51, 52) and forming a second inner surface (53 a) that is not smoothly continuous with the first inner surface (51 a, 52 a). The peripheral wall (43) is provided with a porous portion (60) within a range from a boundary between the scroll portions (51, 52) and the discontinuous portion (53) to an outlet (45) of the air passage (46).

[0008] In the first aspect, the peripheral wall (43) is provided with a porous portion (60) within a region extending from the boundary between the scroll portion (51, 52) and the discontinuous portion (53) to the outlet (45) of the air passage (46). The porous portion (60) has a plurality of holes and functions to suppress the generation of vortex flows. Therefore, by providing the porous portion (60) within this region, it is possible to suppress the generation of vortex flows downstream from the boundary between the scroll portion (51, 52) and the discontinuous portion (53).

[0009] In a second aspect, in the first aspect, the scroll portions (51, 52) are connected to the downstream end of the discontinuous portion (53), and the porous portion (60) is provided in the peripheral wall (43) within a region ranging from the downstream end of the discontinuous portion (53) to the air outlet (45) of the air passage (46).

[0010] In the second aspect, the scroll sections (51, 52) are connected to the downstream ends of the discontinuous sections (53). Therefore, when the air passage (46) passes through the discontinuous section (53), a vortex is generated starting from the boundary between the discontinuous section (53) and the scroll sections (51, 52), causing significant turbulence in the scroll sections (51, 52). In contrast, in the second aspect, the porous section (60) is provided within the region from the downstream end of the discontinuous section (53) to the outlet (45) of the air passage (46), thereby suppressing the generation of a vortex in the scroll sections (51, 52).

[0011] In the third embodiment, in the first or second embodiment, the porous portion (60) constitutes the peripheral wall (43).

[0012] In the third aspect, the peripheral wall (43) is formed of the porous portion (60), which reduces the number of parts of the fan (30).

[0013] In a fourth aspect, in the third aspect, the porous portion (60) is formed from the inner surface to the outer surface of the peripheral wall (43).

[0014] In the fourth aspect, the porous portion 60 is formed from the inner surface 43 a of the peripheral wall 43 to the outer surface 43 b of the peripheral wall 43. The porous portion 60 is an open-cell structure in which a plurality of pores are interconnected, and therefore, air on the inner surface side of the peripheral wall 43 can escape to the outer surface 43 b of the peripheral wall 43 through the porous portion 60. As a result, generation of vortexes due to the porous portion 60 can be suppressed.

[0015] In a fifth aspect, in the first or second aspect, the porous portion (60) is a porous member (61) fixed to the inner surface of the peripheral wall (43).

[0016] In the fifth aspect, the porous member (61), which is the porous portion (60), is provided on the inner surface of the peripheral wall (43), thereby providing the fan (30) with the effect of suppressing the generation of vortex currents.

[0017] A sixth aspect is any one of the first to fifth aspects, wherein the fan is a sirocco fan.

[0018] A seventh aspect is an air conditioner having a fan according to any one of the first to sixth aspects. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a vertical cross-sectional view showing the schematic configuration of an air conditioning apparatus according to this embodiment. [Figure 2] FIG. 2 is a side view of the fan. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is a view of the fan of the first modification, which corresponds to FIG. [Figure 5] FIG. 5 is a view of the fan of the second modification, which corresponds to FIG. [Figure 6] FIG. 6 is an enlarged cross-sectional view of the porous member and its vicinity of the fan of the third modification. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Note that the present disclosure is not limited to the embodiments shown below, and various modifications are possible within the scope of the technical concept of the present disclosure. Since the drawings are intended to conceptually explain the present disclosure, dimensions, ratios, or numbers may be exaggerated or simplified as necessary to facilitate understanding.

[0021] (1) Air conditioning equipment The fan (30) is applied to an air conditioner (10). The air conditioner (10) conditions indoor air. The air conditioner (10) of this embodiment adjusts the temperature of the air. The air conditioner (10) is an outdoor air conditioning unit that supplies outdoor air to the room. As shown in FIG. 1 , the air conditioner (10) has an indoor unit (10a) placed in the ceiling. The indoor unit (10a) has an air conditioning casing (11), and a fan (30) and an indoor heat exchanger (17) housed in the air conditioning casing (11).

[0022] The air conditioning casing (11) has a horizontally elongated rectangular box shape. The air conditioning casing (11) has a first side plate (12) and a second side plate (13) facing each other. An outside air inlet (14) is formed in the first side plate (12), and an air supply port (15) is formed in the second side plate (13). The outside air inlet (14) communicates with an outdoor space via an intake duct. The air supply port (15) communicates with an indoor space via an intake duct. An air conditioning passage (16) through which air flows is formed inside the air conditioning casing (11) from the outside air inlet (14) to the air supply port (15).

[0023] The fan 30 is disposed in the air conditioning passage 16. The fan 30 is a centrifugal fan. Strictly speaking, the fan 30 is a sirocco fan.

[0024] The indoor heat exchanger (17) exchanges heat between air and a refrigerant. The indoor heat exchanger (17) is connected to a refrigerant circuit. The refrigerant circuit includes a compressor, an outdoor heat exchanger, an expansion valve, and the indoor heat exchanger (17). The refrigerant circuit performs a vapor compression refrigeration cycle by circulating the refrigerant. The compressor and the outdoor heat exchanger are provided in the outdoor unit.

[0025] During cooling operation, the compressor and the fan (30) are operated, and the indoor heat exchanger (17) functions as an evaporator. Air flowing into the air conditioning passage (16) from the outside air inlet (14) passes through the indoor heat exchanger (17). The air is cooled by the evaporating refrigerant in the indoor heat exchanger (17). The air cooled in the indoor heat exchanger (17) is supplied to the indoor space via the air supply port (15) and the air supply duct.

[0026] During heating operation, the compressor and the fan (30) are operated, and the indoor heat exchanger (17) functions as a condenser (heat radiator). Air flowing into the air conditioning passage (16) from the outside air inlet (14) passes through the indoor heat exchanger (17). In the indoor heat exchanger (17), the air is heated by the condensing refrigerant. The air heated in the indoor heat exchanger (17) is supplied to the indoor space via the air supply port (15) and the air supply duct.

[0027] (2) Overview of the fan The fan (30) shown in FIGS. 1 to 3 includes a motor (31), a drive shaft (32) that is driven to rotate by the motor (31), an impeller (33) that is connected to the drive shaft (32), and a casing (40) that houses the impeller (33). The motor (31) is supported by a motor support base (34). The drive shaft (32) is connected to the motor (31) and extends horizontally. The fan (30) is a vertically mounted type in which the drive shaft (32) of the motor (31) extends horizontally. The impeller (33) has a rotation shaft that is connected to the drive shaft (32). The impeller (33) has a plurality of blades (33a) that are arranged in the rotation direction (the direction indicated by arrow R in FIG. 3).

[0028] The casing (40) has a cylindrical casing body (40a) and a discharge part (40b) extending from the outer periphery of the casing body (40a) in a tangential direction to the casing body (40a).

[0029] The casing body (40a) has a first wall (41), a second wall (42), and a peripheral wall (43). The first wall (41) is formed at one axial end of the casing body (40a), and the second wall (42) is formed at the other axial end of the casing body (40a). The first wall (41) is located on the motor (31) side across the impeller (33), and the second wall (42) is located on the opposite side of the impeller (33) from the motor (31). The first wall (41) and the second wall (42) are disk-shaped. An inlet (44) is formed in the center of the second wall (42). The peripheral wall (43) surrounds the outer periphery of the impeller (33). The peripheral wall (43) is substantially arc-shaped and conforms to the impeller (33).

[0030] The discharge portion (40b) forms a duct that communicates with the interior of the casing body (40a). The discharge portion (40b) is formed in a rectangular tubular shape with both axial ends open. One axial end opening of the discharge portion (40b) is continuous with the interior of the casing body (40a). The other axial end opening of the discharge portion (40b) forms an air outlet (45). An air passage (46) through which air flows is formed within the casing (40) from the inlet (44) to the air outlet (45).

[0031] (3) Detailed structure of the casing 3, the peripheral wall (43) of the fan (30) of this embodiment has, in order from the upstream side to the downstream side of the air flow in the air passage (46), a first scroll portion (51), a cut portion (53), and a second scroll portion (52). The peripheral wall (43) separates the air passage (46) in the casing (40) from the space outside the casing (40).

[0032] The first scroll portion (51) and the second scroll portion (52) are scroll-shaped walls. A first scroll surface (51a) is formed on the inside of the first scroll portion (51), and a second scroll surface (52a) is formed on the inside of the second scroll portion (52). The first scroll surface (51a) and the second scroll surface (52a) are examples of a first inner surface.

[0033] The first scroll surface (51a) and the second scroll surface (52a) have a scroll shape. Strictly speaking, the first scroll surface (51a) and the second scroll surface (52a) form involute curved surfaces. When viewed in a cross section perpendicular to the axis of the drive shaft (32), the first scroll surface (51a) and the second scroll surface (52a) have an involute curved shape. The curvatures of the first scroll surface (51a) and the second scroll surface (52a) decrease as they progress in the rotation direction of the impeller (33). The curvature of the second scroll surface (52a) is smaller than the curvature of the first scroll surface (51a).

[0034] The cut portion (53) is a discontinuous portion. The cut portion (53) is provided between the first scroll portion (51) and the second scroll portion (52). The cut portion (53) connects the downstream end of the first scroll portion (51) and the upstream end of the second scroll portion (52). In this embodiment, the cut portion (53) is located below the peripheral wall (43). By forming the cut portion (53) below the peripheral wall (43), the vertical height of the casing (40) is reduced compared to a configuration in which the cut portion (53) is not formed in the peripheral wall (43). The cut portion (53) is a flat wall. The cut portion (53) extends horizontally from its upstream end to its downstream end.

[0035] A cut surface (53a) is formed on the inside of the cut portion (53). The cut surface (53a) is a flat surface. The cut surface (53a) extends horizontally from its upstream end to its downstream end. When viewed in a cross section perpendicular to the axis of the drive shaft (32), the cut surface (53a) has a horizontally extending linear shape. The cut surface (53a) is an example of a second inner surface.

[0036] The cut portion (53) bends radially inward of the peripheral wall (43) relative to the first scroll portion (51). Therefore, the first scroll surface (51a) of the first scroll portion (51) is not smoothly continuous with the cut surface (53a) of the cut portion (53). In other words, the first scroll surface (51a) and the cut surface (53a) are not tangent to each other. Specifically, the downstream end of the first scroll surface (51a) and the upstream end of the cut surface (53a) do not share a tangent line.

[0037] The cut portion (53) bends radially inward of the peripheral wall (43) relative to the second scroll portion (52). Therefore, the second scroll surface (52a) of the second scroll portion (52) is not smoothly continuous with the cut surface (53a) of the cut portion (53). In other words, the second scroll surface (52a) and the cut surface (53a) are not tangent to each other. Specifically, the upstream end of the second scroll surface (52a) and the downstream end of the cut surface (53a) do not share a tangent line.

[0038] In FIG. 3, the air flow in the air passage (46) is indicated by dashed arrows. The air passage (46) is formed between the outer peripheral edge of the impeller (33) and the inner surface of the casing (40). In the air passage (46), the closest portion of the impeller (33) and the peripheral wall (43) (near the left end of the impeller (33) in FIG. 3) corresponds to the inlet portion of the air passage (46). In the air passage (46), the radial distance between the cut portion (53) and the impeller (33) is narrower than the radial distance between the second scroll portion (52) and the impeller (33). The radial width of the air passage (46) increases as it advances in the direction of rotation, particularly between the second scroll portion (52) and the impeller (33).

[0039] (4) Generation of vortex currents As described above, the inner surface of the peripheral wall (43) has portions that are not smoothly continuous. Specifically, the cut surface (53a) and the second scroll surface (52a) are not smoothly continuous (not tangent continuous). Therefore, in the air passage (46), air near the inner surface of the peripheral wall (43) is likely to separate from the boundary (a) between the cut surface (53a) and the second scroll surface (52a), thereby generating a vortex. When a vortex is generated starting from the boundary (a), the air passing through the second scroll surface (52a) is significantly turbulent, resulting in noise generation.

[0040] (5) Porous part In this embodiment, to solve the above-mentioned problems, a porous portion (60) is provided in the peripheral wall (43). The porous portion (60) is made of a porous material having a large number of fine interconnected pores. The porous material is a resin, ceramic, metal, or the like. The resin is, for example, a foamed resin. The metal or ceramic is a porous sintered body. The average diameter of the pores (voids) in the porous portion (60) is, for example, in the range of 15 μm to 300 μm. The porosity of the porous portion (60) (= void volume / total volume of the porous portion) is, for example, in the range of 35% to 90%.

[0041] The porous portion (60) is provided in the peripheral wall (43) within a range from the boundary (a) between the cut surface (53a) and the second scroll surface (52a) to the outlet (45). In other words, the porous portion (60) is provided within a range from the downstream end of the cut portion (53) to the outlet (45). The porous portion (60) of this embodiment is provided from the boundary (a) to the outlet (45). The porous portion (60) is formed across both ends of the peripheral wall (43) in the axial direction.

[0042] The porous portion (60) has a function of suppressing the generation of vortex flows in the air passage (46). By providing the porous portion (60) from the boundary (a) to the air outlet (45), the generation of vortex flows originating from the boundary (a) can be suppressed.

[0043] The porous portion (60) constitutes the peripheral wall (43) of the casing (40). The porous portion (60) is formed from the inner surface (43a) to the outer surface (43b) of the peripheral wall (43). In other words, the air passage (46) inside the casing (40) communicates with the outside of the casing (40) through a plurality of holes in the porous portion (60). As a result, when the air pressure in the air passage (46) increases, the air passes through the porous portion (60) in the thickness direction and leaks slightly to the outside of the casing (40). As a result, pressure fluctuations in the air passage (46) can be suppressed. This effectively suppresses the generation of vortexes originating from the boundary at point a.

[0044] In the peripheral wall (43) of this embodiment, the cut portion (53) and the first scroll portion (51) are not provided with a porous portion (60). In other words, the porous portion (60) is provided only in the peripheral wall (43) within a region from the boundary (a) between the cut surface (53a) and the second scroll surface (52a) to the outlet (45). In other words, a non-porous portion, which is not the porous portion (60), is provided upstream of the boundary (a) in the peripheral wall (43). This prevents the portion of the peripheral wall (43) where the porous portion (60) is provided from becoming excessively large.

[0045] (6) Effects of the embodiment The peripheral wall (43) of the fan (30) of this embodiment has a second scroll portion (52) that forms a scroll-shaped second scroll surface (52a), and a cut portion (53) that is bent radially inward relative to the second scroll portion (52) and forms a cut surface (53a) that is not smoothly continuous with the second scroll surface (52a).

[0046] By forming the discontinuous portion (53) in the peripheral wall (43) that is bent radially inward relative to the scroll portions (51, 52), it is possible to reduce the radial size of a portion of the casing (40). On the other hand, when the discontinuous portion (53) is provided in the scroll portions (51, 52), the first inner surfaces (51a, 52a) of the scroll portions (51, 52) and the second inner surface (53a) of the discontinuous portion (53) are not smoothly continuous with each other, and therefore, air is likely to separate from the inner surfaces starting from the boundary between the two, and vortexes are likely to occur starting from the boundary.

[0047] In contrast, the peripheral wall (43) is provided with a porous portion (60) within a range from the boundary (a) between the second scroll portion (52) and the cut portion (53) to the outlet (45) of the air passage (46). The peripheral wall (43) is provided with a porous portion (60) within a range from the boundary (a) between the second scroll portion (52) and the cut portion (53) to the outlet (45) of the air passage (46). This makes it possible to suppress separation of air starting from the boundary (a), and further to suppress the generation of vortex flows. As a result, it is possible to suppress the generation of noise due to vortex flows.

[0048] In this embodiment, the porous portion (60) forms part of the peripheral wall (43). That is, the porous portion (60) also serves as a partition wall for forming the air passage (46). This reduces the number of parts of the fan (30).

[0049] In this embodiment, the porous portion 60 is formed from the inner surface 43 a to the outer surface 43 b of the peripheral wall 43. This suppresses fluctuations in air pressure downstream of the boundary a, thereby effectively suppressing the generation of vortexes originating from the boundary a.

[0050] (6) Variations The above-described fan (30) may have the following modified configuration: The following describes the differences from the above-described embodiment.

[0051] (6-1) Variation 1 In the first modification shown in Fig. 4, the porous portion (60) is provided within a range from the boundary (b) between the first scroll portion (51) and the cut portion (53) to the outlet (45). In other words, the porous portion (60) is provided within a range from the upstream end of the cut portion (53) to the outlet (45). In the example of Fig. 4, the porous portion (60) is provided from the boundary (b) to the outlet (45). The porous portion (60) is not provided in the first scroll portion (51).

[0052] Since the first scroll surface (51a) and the cut surface (53a) are not smoothly connected, air may separate from the boundary (b), potentially generating a vortex. To address this issue, the porous portion (60) provided downstream of the boundary (b) can suppress the generation of a vortex.

[0053] (6-2) Variation 2 In a second modification shown in FIG. 5, the second scroll section (52) is provided with a porous section (60), and the discharge section (40b) is not provided with a porous section (60). In the second modification, the porous section (60) is provided from the boundary (a) to the downstream end of the second scroll section (52). This makes it possible to suppress the generation of a vortex flow originating from the boundary (a). In the example of FIG. 5, the porous section (60) is not provided in the cut section (53); however, as in the first modification, the porous section (60) may be provided in the cut section (53).

[0054] (6-3) Variation 3 In the third modification shown in Fig. 6, a porous member (61) serving as the porous portion (60) is fixed to the inner surface of the peripheral wall (43) of the casing (40). A recess (62) into which the porous member (61) fits is formed in the peripheral wall (43). The porous member (61) is attached to the inside of the recess (62). It is also possible to attach the porous member (61) to the inner surface of the peripheral wall (43) without forming the recess (62) in the peripheral wall (43).

[0055] (6) Other embodiments The fan (30) may be any fan as long as it has a casing (40) in which the scroll portions (51, 52) and the discontinuous portion (53) are formed, and may be, for example, a turbo fan.

[0056] The fan (30) may be horizontally mounted with the drive shaft (32) extending vertically, or may be arranged with the drive shaft (32) extending in another direction.

[0057] The fan (30) may be a double-intake fan in which the inlets (44) are formed in both the first wall (41) and the second wall (42).

[0058] Two or more cut portions 53 may be provided in the peripheral wall 43. The cut portions 53 may be formed on the upper side or the side of the peripheral wall 43.

[0059] The peripheral wall (43) may be provided with a porous portion (60) extending from the middle of the cut portion (53) to a predetermined range of the scroll portions (51, 52).

[0060] The cut portion (53) does not have to be in the shape of a flat plate, but may be in the shape of an arcuate plate as long as it is bent radially inward relative to the scroll portions (51, 52).

[0061] The air conditioner (10) may be an air purifier that purifies the air in a target space, a ventilation device that ventilates the target space, or a humidity control device that adjusts the humidity in the target space.

[0062] The indoor unit (10a) may be of a ceiling-suspended type, a wall-mounted type, or a floor-standing type.

[0063] Although the embodiments and modifications have been described above, it will be understood that various modifications in form and details are possible without departing from the spirit and scope of the claims. Furthermore, the above embodiments, modifications, and other embodiments may be combined or substituted as appropriate as long as the functionality of the subject matter of the present disclosure is not impaired.

[0064] The terms "first," "second," "third," etc. mentioned above are used to distinguish the terms to which these terms are attached, and do not limit the number or order of the terms. [Industrial Applicability]

[0065] As described above, the present disclosure is useful for fans and air conditioners. [Explanation of symbols]

[0066] 10 Air conditioning equipment 30 fans 33 Impeller 40 Casing 43 Peripheral wall 45 Air outlet 46 Air passage 51,52 Scroll section 51a, 52a First inner surface 53 Cut section (discontinuous section) 53a Cut surface (second inner surface) 60 Porous part 61 Porous materials

Claims

1. Impeller (33) and a casing (40) having a peripheral wall (43) surrounding the impeller (33) and forming an air passage (46) between the impeller (33) and the peripheral wall (43); The peripheral wall (43) is a scroll portion (51, 52) forming a scroll-shaped first inner surface (51a, 52a); a discontinuous portion (53) bent radially inward with respect to the scroll portion (51, 52) and forming a second inner surface (53a) that is not smoothly continuous with the first inner surface (51a, 52a), A porous portion (60) is provided in the peripheral wall (43) within a region ranging from a boundary between the scroll portion (51, 52) and the discontinuous portion (53) to an outlet (45) of the air passage (46). fan.

2. the scroll portion (51, 52) is connected to a downstream end of the discontinuous portion (53), The porous portion (60) is provided in the peripheral wall (43) within a range of a region from the downstream end of the discontinuous portion (53) to the air outlet (45) of the air passage (46). The fan according to claim 1 .

3. The porous portion (60) constitutes the peripheral wall (43). The fan according to claim 1 or 2.

4. The porous portion (60) is formed from the inner surface to the outer surface of the peripheral wall (43). The fan according to claim 3 .

5. The porous portion (60) is a porous member (61) fixed to the inner surface of the peripheral wall (43). The fan according to claim 1 or 2.

6. It is a Sirocco fan. The fan according to claim 1 or 2.

7. The fan according to claim 1 or 2 is provided. Air conditioning equipment.

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