Sirocco fan unit and air conditioning device

Abstract

A sirocco fan unit (1) comprises a sirocco-type fan (10) and a casing (20) for accommodating the fan. The casing has a suction port (22) through which a fluid (A) is drawn in. The suction port has provided thereto a suction guide (30) that is curved to extend toward the outer peripheral side (Ro) in the radial direction (R) of the suction port as the suction guide extends toward the upstream side (Fa) in the flowing direction (F) of the fluid. A hollow muffler container (40) that has a space (E) formed in the inside (41) thereof is disposed on the outer peripheral side in the radial direction, relative to the suction guide. The muffler container has provided thereto an opening (42) that is in communication with the space and that faces the inner peripheral side (Ri) in the radial direction. The muffler container is located at a position that overlaps with the suction guide when viewed in the radial direction.

Description

Sirocco fan unit and air conditioner

[0001] The present disclosure relates to a sirocco fan unit and an air conditioner.

[0002] The blower disclosed in Patent Document 1 includes a fan, a casing that surrounds the periphery of the fan and has a bellmouth-shaped suction port on one side, and a bellmouth-shaped orifice having an opening that is concentric with the suction port and has the same diameter as the suction port. The resonance space formed by the orifice resonantly silences the noise emitted from the suction port.

[0003] Japanese Unexamined Patent Application Publication No. 2010 - 90767

[0004] In the blower according to Patent Document 1, a bellmouth is provided at the suction port. The resonance space formed by the orifice is provided only on the upstream side of the bellmouth in the fluid flow direction. The outer peripheral side of the bellmouth is a dead space.

[0005] In the above layout, there are restrictions on increasing the size of the resonance space, which consequently hinders the improvement of the silencing effect. Particularly when applying a sirocco fan with a large amount of noise, in a structure where the resonance space cannot be enlarged as in Patent Document 1, the noise cannot be sufficiently suppressed.

[0006] An object of the present disclosure is to suppress noise in a sirocco fan unit.

[0007] A first aspect of this disclosure relates to a sirocco fan unit (1). This sirocco fan unit (1) comprises a sirocco fan (10) and a casing (20) housing the fan (10), wherein the casing (20) has an inlet (22) into which a fluid (A) is drawn in, and the inlet (22) has a curved suction guide (30) that extends toward the outer circumference (Ro) in the radial direction (R) of the inlet (22) as it extends toward the upstream side (Fa) in the flow direction (F) of the fluid (A). A suction guide (30) is provided, and a hollow sound-dampening container (40) with a space (E) formed inside (41) is positioned on the outer circumference (Ro) side of the suction guide (30) in the radial direction (R), and the sound-dampening container (40) is provided with an opening (42) that communicates with the space (E) and faces the inner circumference (Ri) in the radial direction (R), and the sound-dampening container (40) is positioned to overlap the suction guide (30) when viewed in the radial direction (R).

[0008] According to the first embodiment, noise is easily generated by the rotation of the Sirocco fan (10) housed in the casing (20). A sound-dampening container (40) is positioned on the outer circumference (Ro) of the bell-mouth-shaped intake guide (30). The sound-dampening container (40) functions as a Helmholtz resonator.

[0009] Since the opening (42) of the sound-absorbing container (40) faces the inner circumference (Ri), noise generated from the fan (10) can be effectively silenced. Because the sound-absorbing container (40) is positioned to overlap with the suction guide (30) when viewed in the radial direction (R), the internal space (E) of the sound-absorbing container (40) can be increased, thereby improving the sound-absorbing capacity of the sound-absorbing container (40).

[0010] As described above, noise can be suppressed in the sirocco fan unit (1).

[0011] A second aspect of this disclosure relates to a sirocco fan unit (1) according to the first aspect. In this sirocco fan unit (1), the opening (42) is located upstream (Fa) of the suction guide (30) in the flow direction (F).

[0012] According to the second embodiment, the layout of the opening (42) becomes easier.

[0013] A third aspect of this disclosure relates to a sirocco fan unit (1) according to the first or second aspect. In this sirocco fan unit (1), the sound-dampening container (40) is provided with a curved portion (45) that extends from the upstream side (Fa) in the flow direction (F) to the outer circumference side (Ro) in the radial direction (R), the opening (42) is provided in the curved portion (45), and there is no step (G) between the sound-dampening container (40) and the suction guide (30).

[0014] According to the third embodiment, noise caused by sound waves resonating when they strike a step (G) can be suppressed.

[0015] A fourth aspect of the present disclosure relates to a sirocco fan unit (1) according to any one of the first to third aspects. In this sirocco fan unit (1), the sound-dampening container (40) is provided with a curved portion (45) that extends from the upstream side (Fa) in the flow direction (F) to the outer circumference side (Ro) in the radial direction (R), the opening (42) is provided in the curved portion (45), and the curved portion (45) and the suction guide (30) are connected to each other in a continuous manner.

[0016] According to the fourth embodiment, it is possible to suppress the occurrence of a step between the sound-absorbing container (40) and the suction guide (30). This suppresses noise caused by sound waves resonating when they hit the step.

[0017] A fifth aspect of the present disclosure relates to a sirocco fan unit (1) according to any one of the first to fourth aspects. In this sirocco fan unit (1), the sound-dampening container (40) is provided with a curved portion (45) that extends from the upstream side (Fa) in the flow direction (F) to the outer circumference side (Ro) in the radial direction (R), the opening (42) is provided in the curved portion (45), and the curved portion (45) and the suction guide (30) are integral with each other such that the curved portion (45) also serves as the suction guide (30).

[0018] According to the fifth embodiment, it is possible to suppress the occurrence of a step between the sound-absorbing container (40) and the suction guide (30). This suppresses noise caused by sound waves resonating when they hit the step.

[0019] A sixth aspect of this disclosure relates to a sirocco fan unit (1) according to any one of the first to fifth aspects. In this sirocco fan unit (1), a gap (H) is formed between the suction guide (30) and the sound-dampening container (40) in the radial direction (R).

[0020] According to the sixth embodiment, the degree of freedom in the layout of the sound-absorbing container (40) can be increased.

[0021] A seventh aspect of this disclosure relates to a sirocco fan unit (1) according to any one of the first to sixth aspects. In this sirocco fan unit (1), the opening (42) is partially arranged in the circumferential direction (T) of the intake port (22).

[0022] According to the seventh embodiment, the layout of the opening (42) becomes easier.

[0023] An eighth aspect of the present disclosure relates to a sirocco fan unit (1) according to any one of the first to seventh aspects. In this sirocco fan unit (1), the casing (20) has a tongue (25), and the opening (42) is located on the tongue (25) side of a straight line (L) connecting the tongue (25) and the axis (O) of the fan (10), as viewed in the axial direction (X) of the fan (10).

[0024] According to the eighth aspect, since the fluid (A) generally has a slower flow velocity on the tongue (25) side than on the straight side (L), the inflow of fluid (A) into the opening (42) can be suppressed.

[0025] A ninth aspect of this disclosure relates to an air conditioning system (100), which comprises a sirocco fan unit (1) according to any one of the first to eighth aspects.

[0026] In the ninth aspect, noise can be suppressed in the air conditioning system (100).

[0027] Figure 1 shows a sirocco fan unit (1) according to the first embodiment. Figure 2 shows a fan (10) according to the first embodiment. Figure 3 shows a suction guide (30) and a sound-dampening container (40) according to the first embodiment. Figure 4 shows the positional relationship between the opening (42) and the tongue (25) of the sound-dampening container (40) according to the first embodiment. Figure 5 shows a suction guide (30) and a sound-dampening container (40) according to the second embodiment. Figure 6 shows a suction guide (30) and a sound-dampening container (40) according to the third embodiment. Figure 7 shows a sirocco fan unit (1) according to the fourth embodiment.

[0028] The embodiments of this disclosure will be described in detail below with reference to the drawings. However, this disclosure is not limited to the embodiments shown below, and various modifications are possible without departing from the technical idea of ​​this disclosure. Since the drawings are for conceptual explanation of this disclosure, dimensions, ratios, or numbers may be exaggerated or simplified as necessary for ease of understanding.

[0029] <First Embodiment> (Sirocco Fan Unit) The first embodiment will be described. Figure 1 shows a cross-sectional view of the sirocco fan unit (1). Figure 2 shows a perspective view of the fan (10). The sirocco fan unit (1) is applied to an air purifier (100). The air purifier (100) is an example of an air conditioning system. The air purifier (100) comprises the sirocco fan unit (1) and a filter (101) (see Figure 3).

[0030] The sirocco fan unit (1) comprises a fan (10), a casing (20), a suction guide (30), and a sound-dampening container (40). In the following description, using Figure 1 as a reference, the front of the page is referred to as the rear, the back of the page as the front, left as left, right as right, top as top, and bottom as bottom. Figure 1 is a cross-sectional view of the sirocco fan unit (1) as seen from the rear.

[0031] Fan (10) is a Sirocco-type fan. The direction in which the axis (O) of fan (10) extends is called the axial direction (X). The axis (O) is the rotation axis of fan (10). The side away from the axis (O) is called the outer circumference (Ro) of the radial direction (R). The side approaching the axis (O) is called the inner circumference (R) of the radial direction (R). The radial direction (R) is perpendicular to the axial direction (X). The direction of rotation around the axis (O) and the opposite direction are called the circumferential direction (T). The circumferential direction (T) is perpendicular to the axial direction (X). In the drawing, an arrow is shown indicating the direction of rotation within the circumferential direction (T).

[0032] The fan (10) has a disc (11), a ring (12), and a plurality of blades (13). The disc (11) and the ring (12) are separated in the axial direction (X). The disc (11) is in the forward direction in the axial direction (X). The ring (12) is in the rear direction in the axial direction (X). The blades (13) are plate-shaped with the circumferential direction (T) as the thickness direction. The blades (13) extend longitudinally in the axial direction (X) and shortened radially (R). The blades (13) connect the outer circumference of the disc (11) and the ring (12). The plurality of blades (13) are arranged in the circumferential direction (T). The fan (10) is rotationally driven by, for example, an electric motor (not shown).

[0033] The casing (20) includes a fan housing (21), an inlet (22), a discharge passage (23), an outlet (24), a tongue (25), and an inlet guide (30).

[0034] The fan housing (21) of the casing (20) houses the fan (10). The fan (10) is confined within the casing (20). Within the fan housing (21), the fan (10) extends in the axial direction (X) and rotates counterclockwise (when viewed from the rear) in the circumferential direction (T).

[0035] The intake port (22) is provided in the rear wall portion (21a) of the fan housing portion (21) of the casing (20). The intake port (22) penetrates the rear wall portion (21a) in the axial direction (X). The intake port (22) is circular when viewed in the axial direction (X). The axis (O) of the intake port (22) and the axis (O) of the fan (10) coincide with each other. The inner diameter of the intake port (22) is smaller than the outer diameter of the fan (10). Air (A) is drawn into the intake port (22).

[0036] The discharge passage (23) is located to the right and above the outer periphery (Ro) of the fan housing (21) (fan (10)). The discharge passage (23) extends vertically. More specifically, the discharge passage (23) extends diagonally, slightly to the left as it goes upwards. A discharge port (24) is provided at the upper end of the discharge passage (23). Air (A) is discharged from the discharge port (24).

[0037] The tongue portion (25) is provided between the fan housing portion (21) and the discharge passage (23) in the casing (20). The tongue portion (25) is positioned between the upper right end of the fan housing portion (21) and the lower end of the left wall portion of the discharge passage (23). The tongue portion (25) has a tongue-like shape that protrudes diagonally downward to the right. The tongue portion (25) is the starting point of a spiral volute between the fan housing portion (21) and the discharge passage (23). The tongue portion (25) is positioned to the right and above on the outer circumference (Ro) with respect to the axis (O) of the fan (10) (inlet (22)).

[0038] As will be described in detail later, the suction guide (30) is provided at the suction port (22). As will be described in detail later, the sound-dampening container (40) is located on the outer circumference (Ro) of the suction guide (30) (shown by the dashed line in Figure 1).

[0039] (Airflow) The airflow of the sirocco fan unit (1) will be described. Fig. 3 shows a cross-sectional view of the suction guide (30) and the soundproof container (40) along line III. Air (A) is an example of a fluid. In the following description, the direction in which the air (A) flows is referred to as the flow direction (F). The upstream side in the flow direction (F) may be simply referred to as the upstream side (Fa). The downstream side in the flow direction (F) may be simply referred to as the downstream side (Fb).

[0040] The air (A) is sucked into the casing (20) from outside the casing through the suction port (22). The air (A) sucked by the suction port (22) flows from the rear to the front in the axial direction (X) and flows into the fan housing part (21). At the suction port (22), the upstream side (Fa) in the flow direction (F) is the rear in the axial direction (X). At the suction port (22), the downstream side (Fb) in the flow direction (F) is the front in the axial direction (X).

[0041] In the fan housing part (21), the air (A) is caused by the fan (10) to change its flow direction (F) and flow from below to above, and then flows into the discharge passage (23). The flow of the air (A) becomes swirling at the tongue part (25) between the fan housing part (21) (the fan (10)) and the discharge passage (23).

[0042] The air (A) flows through the discharge passage (23) from below to above and is discharged outside the casing through the discharge port (24).

[0043] (Suction Guide) As shown in Fig. 3, a suction guide (30) is provided at the suction port (22). The suction guide (30) is provided at the opening edge of the suction port (22).

[0044] The suction guide (30) is bellmouth-shaped. As the suction guide (30) extends rearward in the axial direction (X), it extends to the outer peripheral side (Ro) in the radial direction (R). The suction guide (30) is curved so as to extend to the outer peripheral side (Ro) in the radial direction (R) of the suction port (22) as it extends upstream in the flow direction (F) of the air (A).

[0045] The suction guide (30) is provided annularly around the suction port (22) over the entire circumference in the circumferential direction (T) (see FIG. 1).

[0046] (Sound absorption container) As shown in FIG. 3, a sound absorption container (40) is arranged on the outer peripheral side (Ro) in the radial direction (R) rather than the suction guide (30). The sound absorption container (40) is arranged on the rear wall portion (21a) of the fan housing portion (21) in the casing (20).

[0047] The sound absorption container (40) functions as a Helmholtz resonator. In a Helmholtz resonator, the air inside a hollow container with an opening resonates, playing the role of a spring. Due to this resonance of the air, the energy of the sound is absorbed and the sound is attenuated.

[0048] The sound absorption container (40) has a substantially rectangular frame shape in a cross section orthogonal to the circumferential direction (T) (in the cross section of FIG. 3). The sound absorption container (40) is provided annularly around the outer peripheral side (Ro) of the suction guide (30) over the entire circumference in the circumferential direction (T) (see FIG. 1).

[0049] The sound absorption container (40) includes a first wall (40a), a second wall (40b), a third wall (40c), and a fourth wall (40d). The first wall (40a) is on the upstream side (Fa) (rear). The second wall (40b) is on the downstream side (Fb) (front). The third wall (40c) is on the outer peripheral side (Ro). The fourth wall (40d) is on the inner peripheral side (Ri).

[0050] The sound absorption container (40) is hollow. A space (E) is formed inside the sound absorption container (40). The inside (41) is a region surrounded by the first wall (40a), the second wall (40b), the third wall (40c), and the fourth wall (40d). Air is contained in the space (E).

[0051] An opening (42) is provided in the sound absorption container (40). The opening (42) is provided in the fourth wall (40d). The opening (42) faces the inner peripheral side (Ri) in the radial direction (R). Specifically, the opening (42) faces the inner peripheral side (Ri) straight. The opening (42) communicates with the space (E) inside the sound absorption container (40).

[0052] The sound-dampening container (40) is positioned to overlap with the suction guide (30) when viewed in the radial direction (R). In other words, in the flow direction (F), the downstream end (43) of the downstream side (Fb) of the sound-dampening container (40) is located downstream (Fb) of the upstream end (31) of the upstream side (Fa) of the suction guide (30).

[0053] In the sound-dampening container (40), the downstream end (43) is located on the second wall (40b). The upstream end (31) of the suction guide (30) is connected to the fourth wall (40d) of the sound-dampening container (40). The connection point between the upstream end (31) and the fourth wall (40d) is located in the center (44) of the fourth wall (40d) in the flow direction (F).

[0054] The opening (42) is located upstream (Fa) of the central part (44) of the fourth wall (40d) of the sound-absorbing container (40) in the flow direction (F). The opening (42) is located upstream (Fa) of the suction guide (30) in the flow direction (F).

[0055] A step (G) exists between the sound-dampening container (40) and the suction guide (30). The step (G) is formed between the fourth wall (40d) of the sound-dampening container (40) and the upstream end (31) of the suction guide (30). The step (G) is formed perpendicularly by the fourth wall (40d), which extends in the axial direction (X) (flow direction (F)), and the upstream end (31), which extends in the radial direction (R).

[0056] A gap (H) is formed between the suction guide (30) and the sound-absorbing container (40) in the radial direction (R). The gap (H) is formed between the fourth wall (40d) of the sound-absorbing container (40) and the suction guide (30). The gap (H) is in communication with the fan housing (21) of the casing (20).

[0057] (Positional relationship between the opening and tongue of the sound-dampening container) Figure 4 shows the positional relationship between the opening (42) and the tongue (25) of the sound-dampening container (40) as seen from the rear. As described above, the sound-dampening container (40) is provided in an annular shape around the outer circumference (Ro) of the suction guide (30) over the entire circumference in the circumferential direction (T). The opening (42) is partially located in the circumferential direction (T) of the suction port (22). The opening (42) is provided only in a part of the sound-dampening container (40) in the circumferential direction (T). Multiple openings (42) are arranged side by side with spacing in the circumferential direction (T).

[0058] The opening (42) is located on the tongue (25) side of the line (L) connecting the tongue (25) (tip) and the axis (O) of the fan (10), when viewed in the axial direction (X) of the fan (10). The opening (42) is not located on the opposite side of the tongue (25) from the line (L) connecting the tongue (25) and the axis (O), when viewed in the axial direction (X).

[0059] (Effects) The rotation of the Sirocco fan (10) housed in the casing (20) easily generates noise. A sound-dampening container (40) is positioned on the outer circumference (Ro) of the bell-mouth-shaped intake guide (30). The sound-dampening container (40) functions as a Helmholtz resonator.

[0060] Since the opening (42) of the sound-absorbing container (40) faces the inner circumference (Ri), noise generated from the fan (10) can be effectively silenced. Because the sound-absorbing container (40) is positioned to overlap with the suction guide (30) when viewed in the radial direction (R), the internal space (E) of the sound-absorbing container (40) can be increased, thereby improving the sound-absorbing capacity of the sound-absorbing container (40).

[0061] As described above, noise can be suppressed in the sirocco fan unit (1).

[0062] The opening (42) is positioned upstream (Fa) of the suction guide (30) in the flow direction (F). This facilitates the layout of the opening (42).

[0063] A gap (H) is formed between the suction guide (30) and the sound-absorbing container (40) in the radial direction (R). This increases the degree of freedom in the layout of the sound-absorbing container (40).

[0064] The openings (42) are partially arranged in the circumferential direction (T). This facilitates the layout of the openings (42).

[0065] The opening (42) is provided only in a portion of the circumferential direction (T) of the sound-absorbing container (40). This facilitates the layout of the opening (42).

[0066] The opening (42) is located on the tongue (25) side of the straight line (L) connecting the tongue (25) and the axis (O) of the fan (10), when viewed in the axial direction (X) of the fan (10). On the tongue (25) side of the straight line (L), the air (A) flow velocity is generally slower (compared to the side opposite the tongue (25) of the straight line (L), so it is possible to suppress the flow of air (A) into the opening (42).

[0067] The air purifier (100) includes a sirocco fan unit (1). Noise can be suppressed in the air purifier (100).

[0068] <Second Embodiment> A second embodiment will now be described. In the following description, components similar to those in the above embodiment will be denoted by the same reference numerals, and detailed descriptions will be omitted. Figure 5 shows the suction guide (30) and the sound-dampening container (40).

[0069] The sound-dampening container (40) is provided with a curved section (45). The curved section (45) is formed at the connection between the first wall (40a) and the fourth wall (40d). The curved section (45) is an arc shape that is convex on the upstream side (Fa) and the inner circumference side (R). The curved section (45) is curved such that as it extends upstream (Fa) in the flow direction (F), it extends radially (R) towards the outer circumference side (Ro).

[0070] The upstream end (31) of the suction guide (30) is connected to the curved portion (45) of the sound-dampening container (40). The radius of curvature of the suction guide (30) and the radius of curvature of the curved portion (45) are approximately equal. The curved portion (45) and the suction guide (30) are connected to each other in a continuous manner. The curved portion (45) and the suction guide (30) are smoothly connected. There is no step (G) (see Figure 3) between the sound-dampening container (40) and the suction guide (30). When viewed in the radial direction (R), the sound-dampening container (40) is positioned to overlap the suction guide (30).

[0071] The opening (42) is provided in the curved portion (45). The opening (42) faces upstream (Fa) and inward (Ri).

[0072] A gap (H) is formed between the suction guide (30) and the sound-absorbing container (40) in the radial direction (R). The gap (H) is formed between the fourth wall (40d) of the sound-absorbing container (40) and the suction guide (30). The gap (H) is in communication with the fan housing (21) of the casing (20).

[0073] The other configurations are the same as in the first embodiment.

[0074] This can suppress the formation of a step (G) (see Figure 3) between the sound-absorbing container (40) and the suction guide (30). It can also suppress noise (see Figure 3) caused by sound waves (P) resonating when they strike the step (G).

[0075] The sound wave (P) consists of incident sound that travels from inside the casing (20) upstream (Fa) through the intake port (22) to the outside of the casing (20), and reflected sound that travels from outside the casing (20) downstream (Fb) through the intake port (22) to the inside of the casing (20) (Figure 3 illustrates the reflected sound).

[0076] <Third Embodiment> A third embodiment will now be described. In the following description, components similar to those in the above embodiments will be denoted by the same reference numerals, and detailed descriptions will be omitted. Figure 6 shows the suction guide (30) and the sound-dampening container (40).

[0077] The sound-dampening container (40) is provided with a curved section (45). The curved section (45) is formed at the connection between the first wall (40a) and the fourth wall (40d). The curved section (45) is an arc shape that is convex on the upstream side (Fa) and the inner circumference side (R). The curved section (45) is curved such that as it extends upstream (Fa) in the flow direction (F), it extends radially (R) towards the outer circumference side (Ro).

[0078] The curved section (45) and the suction guide (30) are integrally connected, such that the curved section (45) also functions as the suction guide (30). There is no step (G) (see Figure 3) between the sound-dampening container (40) and the suction guide (30). When viewed in the radial direction (R), the sound-dampening container (40) is positioned to overlap the suction guide (30).

[0079] The opening (42) is provided in the curved portion (45). The opening (42) faces upstream (Fa) and inward (Ri).

[0080] There is no gap (H) in the radial direction (R) between the suction guide (30) and the sound-dampening container (40) (see Figures 3 and 5). There may also be no gap between the sound-dampening container (40) and the rear wall portion (21a) of the casing (20).

[0081] The other configurations are the same as in the second embodiment.

[0082] This design prevents the formation of a step (G) (see Figure 3) between the sound-absorbing container (40) and the suction guide (30). It also suppresses noise (see Figure 3) caused by sound waves (P) resonating when they strike the step (G). By integrating the sound-absorbing container (40) and the suction guide (30), the internal space (E) of the sound-absorbing container (40) (41) can be increased.

[0083] <Fourth Embodiment> A fourth embodiment will now be described. In the following description, components similar to those in the above embodiments will be denoted by the same reference numerals, and detailed descriptions will be omitted. Figure 7 shows a sirocco fan unit (1).

[0084] The sirocco fan unit (1) is equipped with an auxiliary guide (50). The auxiliary guide (50) is bell-mouth shaped. The auxiliary guide (50) is curved such that it extends radially (R) outward (Ro) as it extends upstream (F) in the flow direction (F).

[0085] The auxiliary guide (50) is positioned upstream (Fa) of the suction port (22). The auxiliary guide (50) has an opening (51). The axis (O) of the opening (51) of the auxiliary guide (50) coincides with the axis (O) of the suction port (22). The diameter of the opening (51) of the auxiliary guide (50) and the diameter of the suction port (22) are approximately equal.

[0086] A sound-absorbing container (40) is positioned on the outer circumference (Ro) of the suction guide (30) and auxiliary guide (50) in the radial direction (R). The sound-absorbing container (40) is constructed by combining a casing (20), suction guide (30), and auxiliary guide (50), among other things.

[0087] The sound-dampening container (40) is hollow. A space (E) is formed inside (41) the sound-dampening container (40). The space (E) includes a first space (E1) and a second space (E2). The first space (E1) is partitioned by an auxiliary guide (50) and the rear surface of the rear wall portion (21a) of the casing (20). A recess (26) is formed in the rear wall portion (21a) of the casing (20) that is recessed on the downstream side (Fb). The second space (E2) is partitioned by the recess (26) and the suction guide (30).

[0088] The sound-dampening container (40) is provided with an opening (42). The opening (42) faces the inner circumference (R) in the radial direction (R). The opening (42) communicates with space (E).

[0089] The sound-dampening container (40) is positioned to overlap the suction guide (30) and the auxiliary guide (50) when viewed in the radial direction (R). In the flow direction (F), the downstream end (43) of the sound-dampening container (40) (the bottom surface of the recess (26)) is located downstream (Fb) of the upstream end (31) of the suction guide (30).

[0090] The opening (42) is located upstream (Fa) of the upstream end (31) of the suction guide (30) in the flow direction (F). The opening (42) is located downstream (Fb) of the downstream end (52) of the auxiliary guide (50) in the flow direction (F). The opening (42) is located between the upstream end (31) of the suction guide (30) and the downstream end (52) of the auxiliary guide (50) in the flow direction (F).

[0091] The other configurations are the same as in the first embodiment.

[0092] <Other Embodiments> The openings (42) may be arranged around the entire circumference in the circumferential direction (T). In this case, by making the number of openings (42) on the tongue side (25) of the straight line (L) greater than the number of openings (42) on the opposite side of the tongue side (25) of the straight line (L), the inflow of air (A) into the openings (42) can be suppressed.

[0093] In the above embodiment, the sound-dampening container (40) is provided in an annular shape over the entire circumference in the circumferential direction (T), but is not limited to this. The sound-dampening container (40) may be arranged only in a part of the circumferential direction (T), rather than over the entire circumference.

[0094] The fluid (A) is not limited to air.

[0095] The sirocco fan unit (1) may be applied, for example, to a refrigerant-type or other type of air conditioning system (100). The sirocco fan unit (1) may also be used on its own.

[0096] Although embodiments have been described above, it will be understood that various modifications to the form and details are possible without departing from the spirit and scope of the claims. The above embodiments, modifications, and elements of other embodiments may be combined or substituted as appropriate.

[0097] The designations "first," "second," "third," etc., mentioned above are used to distinguish between the terms to which these designations are attached, and do not limit the number or order of those terms.

[0098] O Axis X Axial direction R Radial direction Ro Outer circumference Ri Inner circumference T Circumferential direction F Flow direction Fa Upstream Fb Downstream A Air (fluid) E Space G Step H Gap L Straight line 1 Sirocco fan unit 10 Fan 20 Casing 22 Inlet 25 Tongue 30 Inlet guide 40 Silencer container 41 Interior 42 Opening 45 Curved section 100 Air purifier (air conditioning device)

Claims

1. The device comprises a sirocco fan (10) and a casing (20) housing the fan (10), wherein the casing (20) has a suction port (22) into which a fluid (A) is drawn in, and the suction port (22) is provided with a curved suction guide (30) that extends upstream (Fa) in the flow direction (F) of the fluid (A) and extends outward (Ro) in the radial direction (R) of the suction port (22), and a hollow sound-dampening container (40) having a space (E) formed inside (41) is arranged on the outward side (Ro) of the suction guide (30) in the radial direction (R), and the sound-dampening container (40) is provided with an opening (42) that communicates with the space (E) and faces inward (Ri) in the radial direction (R). The sound-dampening container (40) is a sirocco fan unit located in a position that overlaps with the suction guide (30) when viewed in the radial direction (R).

2. The sirocco fan unit according to claim 1, wherein the opening (42) is located upstream (Fa) of the suction guide (30) in the flow direction (F).

3. The sound-dampening container (40) is provided with a curved portion (45) that extends from the upstream side (Fa) in the flow direction (F) to the outer circumference side (Ro) in the radial direction (R), the opening (42) is provided in the curved portion (45), and there is no step (G) between the sound-dampening container (40) and the suction guide (30), as described in claim 1 or 2.

4. The sound-dampening container (40) is provided with a curved portion (45) that extends toward the outer circumference (Ro) in the radial direction (R) as it extends toward the upstream side (F) in the flow direction (F), the opening (42) is provided in the curved portion (45), and the curved portion (45) and the suction guide (30) are connected to each other in a continuous manner, the sirocco fan unit according to any one of claims 1 to 3.

5. The sound-dampening container (40) is provided with a curved portion (45) that extends toward the outer circumference (Ro) in the radial direction (R) as it extends toward the upstream side (F) in the flow direction (F), the opening (42) is provided in the curved portion (45), and the curved portion (45) and the suction guide (30) are integrally connected such that the curved portion (45) also serves as the suction guide (30), as described in any one of claims 1 to 4.

6. A gap (H) is formed between the suction guide (30) and the sound-dampening container (40) in the radial direction (R), as described in any one of claims 1 to 5.

7. The sirocco fan unit according to any one of claims 1 to 6, wherein the opening (42) is partially arranged in the circumferential direction (T) of the intake port (22).

8. The sirocco fan unit according to any one of claims 1 to 7, wherein the casing (20) has a tongue portion (25), and the opening (42) is located on the tongue portion (25) side of the straight line (L) connecting the tongue portion (25) and the axis (O) of the fan (10), as viewed in the axial direction (X) of the fan (10).

9. An air conditioning system comprising a sirocco fan unit (1) according to any one of claims 1 to 8.

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