JP6494022B2 - Blower - Google Patents

Description

  The present invention relates to a blower used for an air conditioner, for example.

  Conventionally, as this type of blower, a cylindrical impeller that allows air to flow in from an axial end and flow out of the outer peripheral portion, and an outer peripheral side of the impeller are provided so as to flow out of the outer peripheral portion of the impeller. There is known a casing provided with a spiral air passage for allowing the air to flow in the rotation direction of the impeller and a discharge air passage extending from a terminal portion of the spiral air passage toward the discharge port.

  In this blower, by rotating the impeller by an electric motor, the air that has flowed in from the axial end of the impeller is caused to flow out of the outer peripheral portion of the impeller to circulate the spiral air passage, and circulate through the spiral air passage. Air is discharged from the discharge port through the discharge ventilation path.

  The casing is provided with a first side plate provided on one end side of the impeller in the axial direction and an intake end provided on the other end side of the impeller in the axial direction, and sucks air flowing in from the one end side in the axial direction of the impeller into the casing. A second side plate having a mouth, and a tongue that extends between the first side plate and the second side plate in the axial direction of the impeller and separates the start end portion of the spiral air passage and the discharge air passage. doing.

  In the blower, it is desirable that all the air flowing through the spiral air passage is discharged from the discharge port, but a part of the air flowing through the discharge air passage is in the vicinity of the tongue portion, and a gap between the impeller and the inner surface of the casing. A circulation flow returning from the vortex to the spiral air passage can occur. In the blower, there is a problem that, due to the circulation flow, the air discharge amount and static pressure are reduced, and noise during operation is increased.

  Therefore, as a blower capable of suppressing the generation of the circulation flow, the first side plate and the second side plate are arranged on the outer peripheral side of the impeller from the tongue portion to the start end portion of the spiral air passage along the circumferential direction of the impeller. There are known ones that are provided so as to extend toward the spiral air passages and project into the spiral air passages (see, for example, Patent Document 1).

JP 08-135599 A

  However, in a blower provided with a protrusion in the spiral ventilation path, it is possible to suppress the generation of a circulating flow, but the flow of air flowing in the spiral ventilation path and the discharge ventilation path is disturbed by the protrusion. Therefore, it is difficult to sufficiently suppress a decrease in the air discharge amount and static pressure and an increase in noise.

  An object of the present invention is to provide a blower capable of achieving high efficiency and low noise.

  In order to achieve the above object, the present invention is provided so as to surround a cylindrical impeller that allows air to flow in from an axial end and flow out of an outer peripheral portion, and to surround an outer peripheral side of the impeller. And a casing formed with a spiral ventilation path that circulates air that has flowed out from the section in the rotation direction of the impeller and a discharge ventilation path that extends from the terminal end of the spiral ventilation path toward the discharge port. A first side plate provided on one end side of the vehicle in the axial direction, a second side plate provided on the other end side in the axial direction of the impeller and having a suction port, a start end portion of the spiral air passage, and a discharge air passage. The first side plate is provided with a protrusion that extends on the outer peripheral side of the impeller along the circumferential direction of the impeller and protrudes toward the second side plate, The protrusion is centered on the rotation axis of the impeller and is directed from the start end to the end of the spiral air passage. Between the protrusion start position and the tongue that are located within a range of 345 degrees or less, and the height gradually increases from the protrusion start position toward the tongue until reaching the maximum height. In the axial direction, the distance between the end on the first side plate side of the portion where the air of the impeller flows out and the portion having the maximum height is 0.42 times or less the axial dimension of the portion where the air of the impeller flows out And an outer peripheral portion of the impeller on a straight line extending radially outward from the rotation center of the impeller on the outer peripheral side of the protrusion. Between the outer peripheral portion of the impeller and the outer peripheral portion of the inclined surface and the inner peripheral surface of the spiral air passage or the discharge air passage. is there.

  In order to achieve the above object, the present invention is provided so as to surround a cylindrical impeller that allows air to flow in from an axial end and flow out of an outer peripheral portion, and to surround an outer peripheral side of the impeller. And a casing formed with a spiral ventilation path for circulating the air flowing out from the outer peripheral portion in the rotation direction of the impeller and a discharge ventilation path extending from the terminal end of the spiral ventilation path toward the discharge port. A first side plate provided on one end side in the axial direction of the impeller, a second side plate provided on the other end side in the axial direction of the impeller and formed with a suction port, a start end portion of the spiral air passage, and a discharge air passage And the second side plate is provided with a protrusion that extends on the outer peripheral side of the impeller along the circumferential direction of the impeller and protrudes toward the first side plate. The projecting part is centered on the rotating shaft of the impeller, and the end part from the start part of the spiral air passage Toward the tongue from the discharge start position to the maximum height, and the impeller is gradually increased from the discharge start position to the maximum height. In the axial direction, the distance between the end portion on the second side plate side of the portion where the air of the impeller flows out and the portion having the maximum height is 0.45 times the axial dimension of the portion where the air of the impeller flows out. In the outer peripheral side of the protrusion, an inclined surface that gradually decreases in height toward the radially outer side is provided, and on the straight line extending radially outward from the rotation center of the impeller, the outer periphery of the impeller The distance between the outer peripheral part of the inclined surface and the radially outer side of the inclined surface is within a range of 0.15 to 0.65 times the distance between the outer peripheral part of the impeller and the inner peripheral surface of the spiral air passage or the discharge air passage. It is.

  As a result, the flow of air flowing through the spiral ventilation path and the discharge ventilation path is regulated by the protrusion and rectified by the inclined surface, so that the air flowing through the spiral ventilation path and the discharge ventilation path is the start of the spiral ventilation path. The occurrence of a circulating flow returning to the part side is suppressed, and the air that has flowed out of the impeller smoothly flows into the swirl air passage and the discharge air passage, and the secondary flow in the swirl air passage and the discharge air passage is disturbed. Is suppressed.

  In order to achieve the above object, the present invention is provided so as to surround a cylindrical impeller that allows air to flow in from an axial end and flow out of an outer peripheral portion, and to surround an outer peripheral side of the impeller. And a casing formed with a spiral ventilation path for circulating the air flowing out from the outer peripheral portion in the rotation direction of the impeller and a discharge ventilation path extending from the terminal end of the spiral ventilation path toward the discharge port. A first side plate provided on one end side in the axial direction of the impeller, a second side plate provided on the other end side in the axial direction of the impeller and formed with a suction port, a start end portion of the spiral air passage, and a discharge air passage Each of the first side plate and the second side plate is provided so as to extend along a circumferential direction of the impeller from a predetermined position on the outer peripheral side of the impeller toward the tongue. A protrusion that protrudes into the spiral air passage is provided, and the protrusion is located on the radially inner side. An inner surface portion, an outer surface portion located radially outward, and a tip surface portion provided between the tip portion of the inner surface portion and the tip portion of the outer surface portion, and the distance between the inner surface portion and the outer surface portion is , It becomes smaller from the proximal end portion toward the distal end portion.

  As a result, the air that flows radially outward from the outer peripheral portion of the impeller and flows into the end portion side of the spiral air passage is rectified by flowing along the inner surface portion, the tip surface portion, and the outer surface portion, and the spiral air passage and discharge Generation of turbulence such as secondary flow in the ventilation path is suppressed.

  According to the present invention, the air flowing through the spiral air passage and the discharge air passage is prevented from returning to the start end side of the spiral air passage, and the air flowing out from the impeller is smoothly discharged and discharged. Since it is possible to suppress the occurrence of turbulence such as a secondary flow in the spiral ventilation path and the discharge ventilation path, it is possible to achieve high efficiency and low noise.

It is a perspective view of the air blower which shows 1st Embodiment of this invention. It is the figure which looked at the air blower from the inlet side. It is sectional drawing of the casing for demonstrating the 1st protrusion part of a 1st side plate. It is sectional drawing of the casing for demonstrating the 2nd protrusion part of a 2nd side plate. It is the figure which looked at the air blower from the discharge outlet side. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is CC sectional drawing of FIG. It is a graph which shows the relationship between a 1st protrusion start angle and a specific noise. It is a graph which shows the relationship between 1st protrusion height ratio and specific noise. It is a graph which shows the relationship between a 1st inclination width ratio and a specific noise. It is a graph which shows the relationship between a 2nd protrusion start angle and specific noise. It is a graph which shows the relationship between 2nd protrusion height ratio and specific noise. It is a graph which shows the relationship between a 2nd inclination width ratio and a specific noise. It is a graph which compares the relationship between an air volume and a specific noise in the conventional air blower and the air blower of this embodiment. It is a graph which compares the relationship between an air volume and efficiency in the conventional air blower and the air blower of this embodiment. It is sectional drawing of the air blower which shows 2nd Embodiment of this invention. It is a graph which shows the relationship between a 1st protrusion start angle and a specific noise. It is a graph which shows the relationship between a 2nd protrusion start angle and specific noise. It is principal part sectional drawing of the air blower which shows 3rd Embodiment of this invention. It is sectional drawing of the casing for demonstrating the 1st protrusion part of a 1st side plate. It is sectional drawing of the casing for demonstrating the 2nd protrusion part of a 2nd side plate. It is sectional drawing of the casing for demonstrating the 2nd protrusion part of the 2nd side plate which shows 4th Embodiment of this invention.

  1 to 16 show a first embodiment of the present invention.

  As shown in FIG. 1, the blower 1 of the present invention is a centrifugal blower, and is used as, for example, a blower of a vehicle air conditioner.

  As shown in FIG. 6, the blower 1 includes an impeller 10 formed in a cylindrical shape, an electric motor 20 for rotating the impeller 10, and a casing 30 that surrounds an outer peripheral portion and an outer peripheral side of the impeller 10. It is equipped with.

  As shown in FIG. 6, the impeller 10 extends in the axial direction, and has a plurality of blades 11 provided at predetermined intervals in the circumferential direction, and a substrate 12 provided on one end side in the axial direction, And a rim 13 provided on the other axial end side.

  The wing | blade 11 is arrange | positioned so that it may extend toward the outer side from radial inside. The blade 11 has a radially outer side curved toward one side in the circumferential direction with respect to the radially inner side.

  The substrate 12 is a disk-shaped member in which one end portions of a plurality of blades 11 are connected to each other on the outer peripheral side at intervals in the circumferential direction. The board | substrate 12 has the overhang | projection part 12a which protrudes gradually to an axial direction other end side toward the center part from the radial inside of the outer peripheral part to which the one end part of each wing | blade 11 was connected. On the one end surface in the axial direction of the overhanging portion 12a, a concave portion is formed which is gradually depressed toward the other end side in the axial direction toward the radial center with respect to the outer peripheral side.

  The rim 13 is a cylindrical member in which the other end portions of the plurality of blades 11 are connected to each other at intervals in the circumferential direction. The rim 13 extends from the other end of the wing 11 toward the outside in the axial direction and extends obliquely toward the inside in the axial direction and the outside in the radial direction.

  When the impeller 10 is rotated in the circumferential direction about the radial center as a rotation axis, air flows inward from the other axial end side, and the air is radially radiated outward from the gaps of the blades 11. Spill. Air that flows out radially outward of the impeller 10 flows out between the substrate 12 and the rim 13.

  Here, the distance between the outer peripheral portion of the other end surface of the substrate 12 and one end portion of the rim 13 is defined as an air outlet height H.

  As shown in FIG. 6, the electric motor 20 is disposed in a concave portion on one axial end surface of the substrate 12 on one axial end side of the impeller 10. The electric motor 20 has a rotating shaft connected to the central portion of the substrate in the radial direction, and rotates the impeller 10 in one circumferential direction, which is the direction in which the blades 11 are curved.

  As shown in FIG. 6, the casing 30 includes a first side plate 31 provided on one axial end side of the impeller 10, a second side plate 32 provided on the other axial end side of the impeller 10, and a first side plate 31. An outer peripheral plate 33 extending in the circumferential direction of the impeller 10 is provided between the outer peripheral portions of the side plate 31 and the second side plate 32.

  The outer peripheral plate 33 has a spiral spiral portion 33a in which the distance from the rotation shaft of the impeller 10 gradually increases from a predetermined reference position away from the rotation shaft of the impeller 10 toward the rotation direction of the impeller 10; A linear portion 33b extending linearly from the radially outer end of the spiral portion 33a, and a tongue extending in a direction opposite to the spiral portion 33a with a predetermined radius of curvature from the radially inner end of the spiral portion 33a 33c and an extending portion 33d extending from the tongue portion 33c and extending from the straight portion 33b at an interval.

  Further, in the casing 30, as shown in FIG. 6, a suction port 34 for sucking air outside the casing 30 is provided in the second side plate 32. Further, as shown in FIG. 5, the casing 30 has discharge ports 35 for discharging the air sucked into the casing 30 in the first side plate 31, the second side plate 32, the straight portion 33b, and the extending portion 33d. It is provided at the end of the enclosed part.

  As shown in FIGS. 3 and 4, a spiral air passage 36 for circulating the air flowing in from the suction port 34 on the outer peripheral side of the impeller 10 in the rotation direction of the impeller 10 is provided in the casing 30. 31 and the second side plate 32 and between the outer peripheral portion of the impeller 10 and the spiral portion 33a of the outer peripheral plate 33 and the portion of the linear portion 33b on the spiral portion 33a side. Further, in the casing 30, a discharge ventilation path 37 that communicates the terminal end portion of the spiral ventilation path 36 and the discharge port 35 is provided between the first side plate 31 and the second side plate 32 and is discharged from the straight portion 33 b. It is provided between the outlet 35 side and the extending portion 33d.

  In the spiral ventilation path 36, the width dimension of the ventilation path gradually increases in the radial direction and the axial direction from the start end to the end. Further, in the discharge ventilation path 37, the width dimension of the ventilation path gradually increases in the radial direction and the axial direction from the end of the spiral ventilation path 36 toward the discharge port 35. Further, the start end side of the spiral air passage 36 is partitioned from the discharge air passage 37 by the tongue 33c.

  Here, as shown in FIG. 6, the outer peripheral portion of the impeller 10 and the spiral portion 33 a or the straight line on a straight line that extends perpendicularly to the rotational axis of the impeller 10 and extends radially outward from the rotation center of the impeller 10. The distance to the inner surface of the portion 33b is defined as the ventilation path width L.

  As shown in FIGS. 3 and 6, a motor support hole 31 a for supporting the electric motor 20 in a state where the electric motor 20 is penetrated is provided in a substantially central portion of the first side plate 31.

  Further, as shown in FIGS. 3 and 6, a portion of the first side plate 31 located on the radially outer side of the impeller 10 (a portion where the tongue portion 33c is located) protrudes toward the second side plate 32 side. The 1st protrusion 31b extended in the circumferential direction toward the opposite side to the rotation direction of the impeller 10 from the tongue part 33c is provided.

  As shown in FIG. 3, the first protrusion 31 b is arranged in the rotational direction of the impeller 10 with the rotational position of the impeller 10 as a center and the position S of the radially inner end of the spiral portion 33 a as a reference. It is provided between a first protrusion start position, which is a position rotated by one protrusion start angle θL, and the tongue 33c. As shown in FIG. 8, the height of the first protrusion 31b gradually increases from the protrusion start position to the maximum height toward the tongue 33c. Further, a first flat portion 31c extending in a circumferential direction with a predetermined length is provided in the vicinity of the tongue portion 33c of the first protrusion 31b.

  Here, the maximum height dimension of the first protrusion 31b is defined as a first maximum height dimension ZL. As shown in FIG. 8, the first maximum height dimension ZL is the distance from the inner surface of the base plate 12 of the impeller 10 to the maximum height of the first protrusion 31b in the axial direction of the impeller 10. is there.

  Further, a ratio between the air outlet height H and the first maximum height dimension ZL is defined as a first protrusion height ratio (ZL / H).

  Further, as shown in FIGS. 3 and 6, the first slope on the outer peripheral side of the first protrusion 31b gradually decreases in the radial direction over the extending direction of the first protrusion 31b. A surface 31d is provided.

  Here, as shown in FIG. 6, the outer peripheral portion of the impeller 10 and the first inclined surface 31 d on a straight line that extends perpendicularly to the rotational axis of the impeller 10 and extends radially outward from the rotation center of the impeller 10. Is defined as a first inclined width WL. Further, a ratio between the ventilation path width L and the first inclination width WL is defined as a first inclination width ratio (WL / L).

  As shown in FIGS. 4 and 6, a cover portion 32 a that surrounds the other axial end side, the radially inner surface side, and the outer surface side of the rim 13 of the impeller 10 is provided at the edge portion of the suction port 34 of the second side plate 32. It has been.

  Further, as shown in FIGS. 4 and 6, the portion of the second side plate 32 located on the radially outer side of the impeller 10 (the portion where the tongue portion 33 c is located) protrudes toward the first side plate 31 side. A second protrusion 32b extending in the circumferential direction from the tongue 33c toward the side opposite to the rotation direction of the impeller 10 is provided.

  As shown in FIG. 4, the second projecting portion 32 b is arranged in the rotational direction of the impeller 10 with the rotational position of the impeller 10 as a center and the position S of the radially inner end of the spiral portion 33 a as a reference. It is provided between the 2nd protrusion start position located in 2 protrusion start angle (theta) U, and the tongue part 33c. As shown in FIG. 8, the height of the second protrusion 32b gradually increases from the protrusion start position toward the tongue 33c until it reaches the maximum height. In addition, a second flat portion 32c that extends in a circumferential direction with a predetermined length is provided in the vicinity of the tongue portion 33c of the second protrusion 32b.

  Here, the maximum height dimension of the second protrusion 32b is defined as a second maximum height dimension ZU. As shown in FIG. 8, the second maximum height dimension ZU is from the inner end of the rim 13 of the impeller 10 to the maximum height of the second protrusion 32 b in the axial direction of the impeller 10. Distance.

  Further, a ratio between the air outlet height H and the second maximum height dimension ZU is defined as a second protrusion height ratio (ZU / H).

  Further, as shown in FIGS. 4 and 6, a second slope that gradually decreases in height toward the outer side in the radial direction over the extending direction of the second protrusion 32 b is formed on the outer peripheral side of the second protrusion 32 b. A surface 32d is provided.

  Here, as shown in FIG. 6, the outer peripheral portion of the impeller 10 and the second inclined surface 32 d on a straight line that extends perpendicularly to the rotational axis of the impeller 10 and extends radially outward from the rotation center of the impeller 10. The distance from the radially outer end is defined as the second inclined width WU. Further, a ratio between the ventilation path width L and the second inclination width WU is defined as a second inclination width ratio (WU / L).

  In the blower 1 configured as described above, when the electric motor 20 is driven, the impeller 10 rotates in one circumferential direction. When the impeller 10 rotates, the air outside the casing 30 is sucked into the casing 30 through the suction port 34 provided in the second side plate 32. The air sucked into the casing 30 through the suction port 34 flows inward from the other axial end of the impeller 10 and flows out radially from the outer peripheral portion of the impeller 10. The air flowing out radially from the outer peripheral portion of the impeller 10 is rectified while flowing through the spiral air passage 36 and the discharge air passage 37 of the casing 30 and is discharged from the discharge port 35.

  Further, the air flowing through the end side of the spiral air passage 36 and the discharge air passage 37 is swirled by the first protrusion 31 b provided on the first side plate 31 and the second protrusion 32 b provided on the second side plate 32. Inflow to the start end side of the ventilation path 36 is suppressed. Further, the air flowing through the end portion side of the spiral air passage 36 and the discharge air passage 37 is provided on the outer peripheral side of the first inclined surface 31d and the second protrusion 32b provided on the outer peripheral side of the first protrusion 31b. The air flowing out from the impeller 10 by the second inclined surface 32d smoothly flows into the spiral air passage 36 and the discharge air passage 37, and the turbulence such as the secondary flow in the spiral air passage 36 and the discharge air passage 37 is generated. Can be suppressed.

  Further, the air flowing through the end side of the spiral air passage 36 and the discharge air passage 37 causes noise by colliding with the tongue portion 33c, but the first protrusion 31b and the second protrusion 32b protrude. As a result, the surface area of the tongue 33c is reduced, so that the amount of air that collides with the tongue 33c is reduced, and noise is suppressed.

  Next, in the first side plate 31, the first protrusion start angle θL of the first protrusion 31b, the first protrusion height ratio (ZL / H), the first inclination width ratio (WL / L), and the second side plate 32 to obtain appropriate values for the second protrusion start angle θU, the second protrusion height ratio (ZU / H), and the second slope width ratio (WU / L) of the second protrusion 32b. The tests and test results conducted in Section 1 will be described.

  First, in order to obtain an appropriate value for the first protrusion 31b of the first side plate 31, a second side plate having no second protrusion 32b is used, and the first protrusion start angle θL and the first protrusion height ratio ( Two numerical values of ZL / H) and the first slope width ratio (WL / L) are fixed and one numerical value is changed, and the magnitude of noise generated in each is measured.

  In FIG. 9, the first protrusion start angle θL is changed while the first protrusion height ratio (ZL / H = 0.12) and the first inclination width ratio (WL / L = 0.55) are fixed. It is a graph which shows the change of the specific noise value at the time. As shown in FIG. 9, the specific noise value is low when the first protrusion start angle θL is less than 360 degrees (indicating a state where the first protrusion 31 b is not formed). The first protrusion start angle θL is preferably 345 degrees or less, and more preferably 330 degrees or less. Moreover, it becomes a lower state in the range of 90 degrees to 330 degrees. The first protrusion start angle θL is preferably in the range of 180 degrees to 290 degrees as shown in FIG.

  FIG. 10 shows that the first protrusion start angle (θL = 250 °) and the first inclination width ratio (WL / L = 0.55) are fixed, and the first protrusion height ratio (ZL / H) is changed. It is a graph which shows the change of the specific noise value at the time. As shown in FIG. 10, the specific noise value is low in a range of −0.12 to 0.45. The specific noise value is particularly lowered in the range of −0.1 to 0.42. Accordingly, the first protrusion height ratio (ZL / H) is desirably in the range of −0.1 to 0.42.

  Here, the negative value in the first protrusion height ratio (ZL / H) is such that the portion where the maximum height of the first protrusion 31b is higher than that of the inner surface of the base plate 12 of the impeller 10 is greater than that of the impeller 10. The state located in the axial direction outer side is shown.

  FIG. 11 shows that the first inclination start ratio (θL = 250 °) and the first protrusion height ratio (ZL / H = 0.12) are fixed and the first inclination width ratio (WL / L) is changed. It is a graph which shows the change of the specific noise value at the time. As shown in FIG. 11, the specific noise value is in a low state except when the first protrusion 31b is not provided. The specific noise value is particularly reduced when the first slope width ratio (WL / L) is in the range of 0.25 to 0.8. Therefore, the first slope width ratio (WL / L) is desirably in the range of 0.25 to 0.8.

  In addition, in order to obtain an appropriate value for the second protrusion 32b of the second side plate 32, a first side plate that does not have the first protrusion 31b is used, and the second protrusion start angle θU and the second protrusion height ratio ( Two numerical values of ZU / H) and the second slope width ratio (WU / L) are fixed and one numerical value is changed, and the magnitude of noise generated in each is measured.

  In FIG. 12, the second protrusion start angle θU is changed while the second protrusion height ratio (ZU / H = 0.1) and the second inclination width ratio (WU / L = 0.4) are fixed. It is a graph which shows the change of the specific noise value at the time. As shown in FIG. 12, the specific noise value is low when the second protrusion start angle θU is less than 360 degrees. The second protrusion start angle θU is preferably 345 degrees or less, and more preferably in the range of 120 degrees to 330 degrees. Moreover, it will be in a lower state in the range of 180 degrees to 315 degrees.

  FIG. 13 shows that the second protrusion start angle (θU = 270 °) and the second slope width ratio (WU / L = 0.4) are fixed, and the second protrusion height ratio (ZU / H) is changed. It is a graph which shows the change of the specific noise value at the time. As shown in FIG. 13, the specific noise value is low in the range of −0.1 to 0.5. The specific noise value is particularly lowered in the range of -0.08 to 0.45. Therefore, the second protrusion height ratio (ZU / H) is desirably in the range of −0.08 to 0.45.

  Here, the negative value in the second protrusion height ratio (ZU / H) indicates that the portion where the maximum height of the second protrusion 32b is higher than the inner surface of the rim 13 of the impeller 10 is greater than that of the impeller 10. The state located in the axial direction outer side is shown.

  FIG. 14 shows that the second protrusion start angle (θU = 270 °) and the second protrusion height ratio (ZU / H = 0.1) are fixed and the second inclination width ratio (WU / L) is changed. It is a graph which shows the change of the specific noise value at the time. As shown in FIG. 14, the specific noise value has a low second slope width ratio (WU / L) in the range of 0.05 to 0.75. The specific noise value is particularly lowered when the second slope width ratio (WU / L) is in the range of 0.15 to 0.65. Therefore, the second slope width ratio (WU / L) is desirably in the range of 0.15 to 0.65.

  The result of the test comparing the blower to which the appropriate values obtained by the respective tests are applied and the conventional blower without the first protrusion 31b and the second protrusion 32b of the present embodiment will be described.

  FIG. 15 shows the change in specific noise value when the air volume of each blower is changed (specific noise characteristics). As shown in FIG. 15, the blower 1 to which the appropriate value is applied has a lower specific noise value than the conventional blower when the air volume is 150 m 3 / h or more. It can be seen that the specific noise value has the largest difference when the air volume is 450 m <3> / h, and the noise reduction effect appears in a wide air volume range.

  FIG. 16 shows changes in fan efficiency when the air volume of each fan is changed (blower efficiency characteristics). As shown in FIG. 16, the blower 1 to which the appropriate value is applied has higher blower efficiency than the conventional blower in all the air volumes.

  Thus, according to the blower of the present embodiment, the first side plate 31 is provided so that the outer peripheral side of the impeller 10 extends along the circumferential direction of the impeller 10 and toward the second side plate 32 side. A protruding first protrusion 31b is provided, and the first protrusion 31b is located within a range of 345 degrees or less from the start end to the end of the spiral air passage 36 around the rotation axis of the impeller 10. Is provided between the protruding start position and the tongue 33c, and gradually increases in height toward the tongue 33c from the protruding start position to the maximum height, and in the axial direction of the impeller 10, the impeller 10 The distance ZL between the end portion on the first side plate 31 side of the portion where the air flows out and the portion having the maximum height is 0.42 times or less the axial dimension H of the portion where the air of the impeller 10 flows out. On the outer peripheral side of the first protrusion 31b, gradually toward the radially outer side. A first inclined surface 31d having a small height is provided, and on the straight line extending radially outward from the rotation center of the impeller 10, the outer peripheral portion of the impeller 10 and the radially outer end of the first inclined surface 31d The distance WL is 0.25 to 0.8 times the distance L between the outer peripheral portion of the impeller 10 and the inner peripheral surface of the spiral air passage 36 or the discharge air passage 37.

  Further, the second side plate 32 is provided with a second protrusion 32b that is provided so as to extend on the outer peripheral side of the impeller 10 along the circumferential direction of the impeller 10 and protrudes toward the first side plate 31 side, The second protrusion 32b is located between the protrusion start position and the tongue 33c located within a range of 345 degrees or less from the start end to the end of the spiral air passage 36 around the rotation axis of the impeller 10. The second side plate 32 of the portion that is gradually increased in height toward the tongue portion 33c from the discharge start position and reaches the maximum height and flows out the air of the impeller 10 in the axial direction of the impeller 10. The distance ZU between the end portion on the side and the portion having the maximum height is 0.15 times or less the axial dimension H of the portion through which the air of the impeller 10 flows out, and the outer peripheral side of the second protrusion 32b is The second inclined surface 32d whose height gradually decreases toward the outside in the radial direction. The distance WU between the outer peripheral portion of the impeller 10 and the radially outer end of the second inclined surface 32d on a straight line provided and extending radially outward from the rotation center of the impeller 10 is the outer peripheral portion of the impeller 10 And 0.15 to 0.65 times the distance L between the spiral air passage 36 and the inner peripheral surface of the discharge air passage 37.

  Thereby, the air flowing through the spiral air passage 36 and the discharge air passage 37 is prevented from returning to the starting end side of the spiral air passage 36, and the air flowing out from the impeller 10 is smoothly discharged. In addition, it is possible to suppress the occurrence of turbulence such as a secondary flow in the spiral ventilation path 36 and the discharge ventilation path 37 and to increase the efficiency and reduce the noise. Become.

  Moreover, the 1st flat part 31c and the 2nd flat part 32c which are extended in the circumferential direction by the maximum height ZL and ZU are provided in the tongue part 33c side of the 1st protrusion part 31b and the 2nd protrusion part 32b.

  As a result, it is possible to suppress the occurrence of the circulation flow and turbulence of the air flowing through the spiral ventilation path 36 and the discharge ventilation path 37.

   17 to 19 show a second embodiment of the present invention. In addition, the same code | symbol is attached | subjected and shown to the component similar to the said embodiment.

  As shown in FIG. 17, the first protrusion 31b of the present embodiment gradually increases until it reaches a maximum height in the range of 30 to 60 degrees in the rotation direction of the impeller 10 from the protrusion start position toward the tongue 33c. The first flat part 31c is provided in the range from the position where the height dimension is increased to the tongue part 33c.

  In addition, as shown in FIG. 17, the second protrusion 32b gradually increases from the protrusion start position toward the tongue 33c until it reaches the maximum height in the range of 30 to 60 degrees in the rotational direction of the impeller 10. The second flat portion 32c is provided in a range from the position where the height is increased to the maximum height to the tongue portion 33c.

  In the blower 1 configured as described above, the first protrusion start angle θL of the first protrusion 31b, the first protrusion height ratio (ZL / H), and the first side plate 31 in the same manner as in the above embodiment. The first inclination width ratio (WL / L), the second protrusion start angle θU of the second protrusion 32b, the second protrusion height ratio (ZU / H), and the second inclination width ratio (second side plate 32) WU / L) and the tests conducted to obtain appropriate values and test results will be described.

  In FIG. 18, the first protrusion start angle θL was changed with the first protrusion height ratio (ZL / H = 0.12) and the first inclination width ratio (WL / L = 0.55) fixed. It is a graph which shows the change of the specific noise value at the time. As shown in FIG. 18, the specific noise value is low when the first protrusion start angle θL is less than 360 degrees (indicating a state in which the first protrusion 31b is not formed). The first protrusion start angle θL is preferably 345 degrees or less, and more preferably 330 degrees or less. Moreover, it becomes a lower state in the range of 90 degrees to 330 degrees. As shown in FIG. 18, the first protrusion start angle θL is preferably in the range of 180 degrees to 290 degrees.

  In a test where the first protrusion start angle (θL = 250 °) and the first slope width ratio (WL / L = 0.55) are fixed and the first protrusion height ratio (ZL / H) is changed, the ratio The noise value is low in the range of −0.12 to 0.45, as in the above embodiment. The specific noise value is particularly lowered in the range of −0.1 to 0.42. Accordingly, the first protrusion height ratio (ZL / H) is desirably in the range of −0.1 to 0.42.

  In a test in which the first inclination start ratio (θL = 250 °) and the first protrusion height ratio (ZL / H = 0.12) are fixed and the first inclination width ratio (WL / L) is changed, the ratio The noise level is in a low state except for the case where the first protrusion 31b is not provided, as in the above embodiment. The specific noise value is particularly reduced when the first slope width ratio (WL / L) is in the range of 0.25 to 0.8. Therefore, the first slope width ratio (WL / L) is desirably in the range of 0.25 to 0.8.

  In addition, in order to obtain an appropriate value for the second protrusion 32b of the second side plate 32, a first side plate that does not have the first protrusion 31b is used, and the second protrusion start angle θU and the second protrusion height ratio ( Two numerical values of ZU / H) and the second slope width ratio (WU / L) are fixed and one numerical value is changed, and the magnitude of noise generated in each is measured.

  In FIG. 19, the second protrusion start angle θU is changed while the second protrusion height ratio (ZU / H = 0.1) and the second inclination width ratio (WU / L = 0.4) are fixed. It is a graph which shows the change of the specific noise value at the time. As shown in FIG. 19, the specific noise value is low when the second protrusion start angle θU is less than 360 degrees. The second protrusion start angle θU is preferably 345 degrees or less, and more preferably in the range of 45 degrees to 330 degrees. Moreover, it becomes a lower state in the range of 60 degrees to 330 degrees. The second protrusion start angle θU is preferably in the range of 150 degrees to 300 degrees as shown in FIG.

  In a test in which the second protrusion start angle (θU = 270 °) and the second slope width ratio (WU / L = 0.4) are fixed and the second protrusion height ratio (ZU / H) is changed, the ratio is The noise level is low in the range of -0.1 to 0.5. The specific noise value is particularly lowered in the range of -0.08 to 0.5. Therefore, the second protrusion height ratio (ZU / H) is desirably in the range of -0.08 to 0.5.

  In a test in which the second inclination width ratio (WU / L) is changed by fixing the second protrusion start angle (θU = 270 °) and the second protrusion height ratio (ZU / H = 0.1), the ratio As in the above embodiment, the second slope width ratio (WU / L) is low in the range of 0.05 to 0.75. The specific noise value is particularly lowered when the second slope width ratio (WU / L) is in the range of 0.15 to 0.65. Therefore, the second slope width ratio (WU / L) is desirably in the range of 0.15 to 0.65.

  As described above, according to the blower of the present embodiment, the generation of a circulating flow in which the air flowing through the spiral ventilation path 36 and the discharge ventilation path 37 returns to the start end side of the spiral ventilation path 36 is suppressed as in the above-described embodiment. At the same time, the air flowing out from the impeller 10 can smoothly flow into the spiral air passage 36 and the discharge air passage 37, and the occurrence of turbulence such as a secondary flow in the spiral air passage 36 and the discharge air passage 37 can be suppressed. Therefore, high efficiency and low noise can be achieved.

  20 to 22 show a third embodiment of the present invention. In addition, the same code | symbol is attached | subjected and shown to the component similar to the said embodiment.

  The first and second side plates 31 and 32 of the present embodiment are provided so as to extend from a predetermined position on the outer peripheral side of the impeller 10 toward the tongue portion 33c along the circumferential direction of the impeller 10, respectively. First and second projecting portions 41 and 42 projecting into the path 36 are provided.

  As shown in FIG. 20, the first and second projecting portions 41 and 42 are first and second inner side surface portions 41a and 42a located on the radially inner side, and first and second outer side surface portions located on the radially outer side. 41b, 42b, and first and second front end surface portions 41c, 42c provided between the front end portions of the first and second inner side surface portions 41a, 42a and the front end portions of the first and second outer side surface portions 41b, 42b, have.

  As shown in FIG. 20, the first and second protrusions 41 and 42 have a distance between the first and second inner side surfaces 41a and 42a and the first and second outer side surfaces 41b and 42b from the proximal end to the distal end. It becomes smaller toward the part. That is, the first and second protrusions 41 and 42 have a trapezoidal cross-sectional shape.

  The first and second protrusions 41 and 42 are provided so as to extend in the circumferential direction of the impeller 10 between the first and second inner side surface portions 41a and 42a and the first and second tip end surface portions 41c and 42c. It has the 1st and 2nd inner curved surface part 41d and 42d formed in the curved surface form.

  The first and second protrusions 41 and 42 are provided so as to extend in the circumferential direction of the impeller 10 between the first and second outer surface portions 41b and 42b and the first and second tip end surface portions 41c and 42c. The first and second outer curved surface portions 41e and 42e are formed in a curved shape.

  The first and second inner curved surface portions 41d and 42d and the first and second outer curved surface portions 41e and 42e have a curvature radius that gradually increases from a predetermined position on the outer peripheral side of the impeller 10 toward the tongue portion 33c. Is formed. The first and second outer curved surface portions 41e and 42e are formed larger than the radius of curvature of the first and second inner curved surface portions 41d and 42d in the radial direction of the impeller 10.

  As shown in FIGS. 21 and 22, the first and second projecting portions 41 and 42 are such that the first and second tip end surface portions 41 c and 42 c are directed from the predetermined position on the outer peripheral side of the impeller 10 toward the tongue portion 33 c. The width dimension is gradually increased. The width dimensions W1 and W2 of the first and second tip surface portions 41c and 42c are formed substantially the same as the width dimension of the tongue portion 33c in the vicinity of the tongue portion 33c. Here, as shown in FIGS. 21 and 22, the width dimension of the tongue portion 33c is a position S that is a contact point between the radially inner end portion of the spiral portion 33a and the radially inner end portion of the tongue portion 33c. And a position E that is a contact point between the radially outer end of the tongue 33c and the end of the extended portion 33d. Further, the width dimension of the first and second tip surface portions 41c and 42c is substantially the same as the width dimension of the tongue portion 33c, which is within a range of about 0.8 to 1.3 times the width dimension of the tongue portion 33c. .

  The first and second tip surface portions 41c and 42c are directed from the plane orthogonal to the axial direction of the impeller 10 or from the first and second inner surface portions 41a and 42a to the first and second outer surface portions 41b and 42b. It is a surface that is inclined downward. The inclination angle when the first and second tip surface portions 41c and 42c are inclined downward is in the range of 0 to 20 degrees.

  As shown in FIGS. 21 and 22, the first and second protrusions 41 and 42 are formed on the wall surface of the discharge air passage 37 from the first and second outer side surfaces 41 b and 42 b toward the discharge port 35 from the tongue 33 c. It has the 1st and 2nd extension outer side surface parts 41f and 42f extended along. The first and second extended outer surface portions 41 f and 42 f gradually decrease in the amount of protrusion from the wall surface of the discharge ventilation path 37 toward the discharge port 35.

  In the blower configured as described above, the air flowing through the end portion side of the spiral air passage 36 and the discharge air passage 37 is provided in the first protrusion 41 and the second side plate 32 provided in the first side plate 31. Further, the second protrusion 42 suppresses the inflow of the spiral air passage 36 to the start end side.

  In addition, the air that flows radially outward from the outer peripheral portion of the impeller 10 and flows into the terminal end side of the spiral air passage 36 is the first and second protrusions 41 and 42 having a trapezoidal cross section. It rectifies by flowing along the first and second inner side surface portions 41a and 42a, the first and second tip end surface portions 41c and 42c, and the first and second outer side surface portions 41b and 42b.

  The air that flows radially outward from the outer peripheral portion of the impeller 10 and flows into the spiral air passage 36 gradually increases in flow rate from the start end portion to the end portion of the spiral air passage 36. However, the air with a large flow rate that flows in the radial direction with respect to the terminal end side of the spiral air passage 36 is rectified by flowing along the first and second tip end face portions 41c and 42c having a large width dimension.

  The first and second tip surface portions 41c and 42c are flat surfaces orthogonal to the axial direction of the impeller 10, or from the first and second inner surface portions 41a and 42a to the first and second outer surface portions 41b and 42b. It is a surface which becomes a downward slope toward. For this reason, the air flowing in the radial direction of the impeller 10 with respect to the spiral air passage 36 does not peel off at the first and second tip end surface portions 41c and 42c, and is generated on the first and second outer side surface portions 41b and 42b. Rectified to flow along.

  Furthermore, the air flowing along the first and second inner side surface portions 41a and 42a of the first and second protrusions 41 and 42 is along the first and second inner curved surface portions 41d and 42d formed in a curved surface shape. To reach the first and second tip surface portions 41c, 42c. Further, the air flowing along the radial direction of the impeller 10 through the first and second tip surface portions 41c and 42c is first and second along the first and second outer curved surface portions 41e and 42e formed in a curved shape. It reaches the second outer surface portions 41b and 42b.

  Here, the first and second outer curved surface portions 41e and 42e are formed to have a larger radius of curvature than the first and second inner curved surface portions 41d and 42d. For this reason, the air flowing in the radial direction of the impeller 10 with respect to the spiral air passage 36 does not peel off at the first and second outer surface portions 41b and 42b, but travels along the first and second outer surface portions 41b and 42b. Rectified to flow.

  Further, the first and second inner curved surface portions 41d and 42d and the first and second outer curved surface portions 41e and 42e each have a larger radius of curvature toward the tongue portion 33c. For this reason, the air of a large flow rate that flows in the radial direction with respect to the terminal end side of the spiral air passage 36 is the first and second inner side surface portions 41a and 42a, the first and second front end surface portions 41c and 42c, and the first and second The flow is rectified so as to flow along the second outer surface portions 41b and 42b.

  Further, the air flowing from the vicinity of the tongue portion 33 c toward the discharge port 35 extends along the wall surface of the discharge ventilation path 37, and the amount of protrusion from the wall surface of the discharge ventilation path 37 gradually increases toward the discharge port 35. The flow is guided to the discharge port 35 without being disturbed by the first and second extended outer surface portions 41f and 42f formed small.

  As described above, according to the blower of the present embodiment, the first and second protrusions 41 and 42 are the first and second inner side surface portions 41a and 42a located on the radially inner side and the first radially located outer side. First and second tips provided between the leading ends of the first and second outer side surfaces 41b and 42b and the leading ends of the first and second outer side surfaces 41b and 42b. It has surface portions 41c and 42c, and the distance between the first and second inner side surface portions 41a and 42a and the first and second outer side surface portions 41b and 42b decreases from the base end portion toward the tip end portion.

  Thereby, the air flowing radially outward from the outer peripheral portion of the impeller 10 and flowing into the terminal end side of the spiral air passage 36 is converted into the first and second inner side surface portions 41a and 42a, the first and second tip end surface portions 41c, 42c is rectified by flowing along the first and second outer surface portions 41b and 42b, so that the air flowing through the spiral ventilation path 36 and the discharge ventilation path 37 returns to the start end side of the spiral ventilation path 36. While suppressing generation | occurrence | production, the air which flowed out from the impeller 10 can be smoothly flowed in in the spiral ventilation path 36 and the discharge ventilation path 37, and it becomes possible to achieve high efficiency and low noise.

  The first and second tip surface portions 41c and 42c are formed so that the width dimension increases from a predetermined position on the outer peripheral side of the impeller 10 toward the tongue portion 33c. The width dimension of the tongue portion 33c is It is substantially the same as the width dimension of 33c.

  Accordingly, air having a large flow rate flowing in the radial direction with respect to the terminal end side of the spiral air passage 36 is reliably rectified by flowing along the first and second tip end face portions 41c and 42c having a large width dimension. It becomes possible.

  In addition, the first and second protrusions 41 and 42 have first and second outer surface portions 41b and 42b extending from the tongue portion 33c toward the discharge port 35 along the side wall of the discharge ventilation passage 37 only. It has 2 extended outer side surface parts 41f and 42f, and the 1st and 2nd extended outer side surface parts 41f and 42f become small toward the discharge port 35, and the protrusion amount becomes small.

  Thereby, it becomes possible to guide to the discharge port 35 without disturbing the flow of the air flowing through the discharge ventilation path 37.

  The first and second protrusions 41 and 42 are first and second curved surfaces formed between the first and second inner side surface portions 41a and 42a and the first and second tip end surface portions 41c and 42c. First and second outer curved surfaces having two inner curved surface portions 41d and 42d and formed between the first and second outer surface portions 41b and 42b and the first and second tip surface portions 41c and 42c. The first and second outer curved surface portions 41e and 42e have a radius of curvature larger than that of the first and second inner curved surface portions 41d and 42d.

  Thereby, the air flowing in the radial direction with respect to the spiral air passage 36 flows along the first and second outer surface portions 41b and 42b without causing separation at the first and second outer surface portions 41b and 42b. Thus, it becomes possible to rectify.

  The first and second inner curved surface portions 41d and 42d and the first and second outer curved surface portions 41e and 42e are formed so that the radius of curvature increases toward the tongue portion 33c.

  As a result, a large flow rate of air flowing in the radial direction with respect to the terminal end side of the spiral air passage 36 is supplied to the first and second inner side surface portions 41a and 42a, the first and second tip end surface portions 41c and 42c, It becomes possible to rectify so as to flow along the second outer surface portions 41b and 42b.

  Further, the first and second tip surface portions 41c and 42c are surfaces orthogonal to the axial direction of the impeller 10, or the first and second outer surface portions 41b and 42b from the first and second inner surface portions 41a and 42a. The surface has a downward slope toward the surface.

  Thus, the air flowing in the radial direction with respect to the spiral air passage 36 flows along the first and second outer surface portions 41b and 42b without causing separation at the first and second tip surface portions 41c and 42c. Thus, it becomes possible to rectify.

  FIG. 23 shows a fourth embodiment of the present invention. In addition, the same code | symbol is attached | subjected and shown to the component similar to the said embodiment. In the present embodiment, only the second protrusion 42 of the second side plate 32 will be described, but the first side plate 31 has the same configuration.

  The second protrusion 42 of the second side plate 32 of the present embodiment has a second extended protrusion 42g extending from the tongue 33c to the start end side of the spiral air passage 36 in addition to the same configuration as in the third embodiment. doing.

  The second extending protrusion 42g is provided within a range of 120 degrees from the start end to the end of the spiral air passage 36 around the rotation axis of the impeller 10. Further, the second extension protrusion 42g is formed so that the protrusion height gradually decreases toward the terminal end of the spiral air passage 36.

  Further, the axial end dimension of the spiral air passage 36 on the start end side is reduced by projecting the second extended protrusion 42 g into the spiral air passage 36 from the second side plate 32.

  In the blower configured as described above, in addition to the air flowing in the same manner as in the third embodiment, the air flowing through the radially inner side of the second protrusion 42 extends along the second extended protrusion 42g. By circulating, disturbance of the air flow is suppressed.

  In addition, the circulating air is rectified on the start end side of the spiral air passage 36 where the flow rate of air is small because the axial dimension is small.

  As described above, according to the blower of the present embodiment, as in the third embodiment, the air flowing radially outward from the outer peripheral portion of the impeller 10 and flowing into the end portion side of the spiral air passage 36 is the first. And since it rectifies | straightens by flowing along 2nd inner side surface part 41a, 42a, 1st and 2nd front end surface part 41c, 42c, 1st and 2nd outer side surface part 41b, 42b, the spiral ventilation path 36 and the discharge ventilation path 37 The generation of a circulating flow that returns to the start end side of the spiral air passage 36 is suppressed, and the air that has flowed out of the impeller 10 is smoothly flowed into the spiral air passage 36 and the discharge air passage 37 to improve efficiency. In addition, the noise can be reduced.

  The second protrusion 42 has a second extension protrusion 42g extending from the tongue 33c toward the start end of the spiral air passage 36, and the second extension protrusion 42g is centered on the rotation axis of the impeller 10. The spiral air passage 36 is provided within a range of 120 degrees from the start end portion toward the terminal end portion, and is formed so that the protruding height gradually decreases toward the terminal end portion of the spiral air passage 36.

  Thereby, the air flowing in the radial direction of the second protrusion 42 is circulated along the second extension protrusion 42g, so that the turbulence of the air flow can be suppressed. Moreover, since the dimension of the axial direction becomes small at the start end side of the spiral air passage 36 where the flow rate of air is small, it becomes possible to rectify the circulating air.

  In addition, in the said embodiment, it is also possible to apply to ventilation means, such as an air conditioning apparatus in the room | chamber interior of a building, and a ventilation apparatus other than the sending means of the air conditioning apparatus for vehicles.

  DESCRIPTION OF SYMBOLS 1 ... Blower, 10 ... Impeller, 30 ... Casing, 31 ... 1st side plate, 31b ... 1st protrusion, 31c ... 1st flat part, 31d ... 1st inclined surface, 32 ... 2nd side plate, 32b ... 2nd Projection, 32c: second flat part, 32d: second inclined surface, 33c ... tongue, 34 ... suction port, 35 ... discharge port, 36 ... spiral air passage, 37 ... discharge air passage, 41 ... first protrusion 41a ... first inner side surface portion, 41b ... first outer surface portion, 41c ... first tip surface portion, 41d ... first inner curved surface portion, 41e ... first outer curved surface portion, 41f ... first extended outer surface portion, 42 ... second. Projection, 42a ... second inner surface, 42b ... second outer surface, 42c ... second tip surface, 42d ... second inner curved surface, 42e ... second outer curved surface, 42f ... second extended outer surface, 42g ... Second extension protrusion.

Claims (10)

A cylindrical impeller that allows air to flow in from an axial end and flow out of the outer periphery; and
A spiral air passage that is provided so as to surround the outer peripheral side of the impeller and that flows air that flows out of the outer peripheral portion of the impeller in the rotation direction of the impeller, and a discharge air that extends from the end portion of the spiral air passage toward the discharge port A casing formed with a path,
The casing includes a first side plate provided on one end side in the axial direction of the impeller, a second side plate provided on the other end side in the axial direction of the impeller and formed with a suction port, a start end portion of the spiral air passage, and a discharge A tongue that separates the ventilation path;
The first side plate is provided so as to extend the outer peripheral side of the impeller along the circumferential direction of the impeller, and is provided with a protrusion that protrudes toward the second side plate side,
The protrusion is
Centering on the rotation axis of the impeller, it is provided between the protrusion start position and the tongue portion located within a range of 345 degrees or less from the start end portion of the spiral air passage toward the end portion,
From the protruding start position to the maximum height, the height gradually increases toward the tongue,
In the axial direction of the impeller, the distance between the end portion on the first side plate side of the portion where the air of the impeller flows out and the portion having the maximum height is 0. 42 times or less,
On the outer peripheral side of the protrusion,
An inclined surface that gradually decreases in height toward the radially outer side is provided,
On the straight line extending radially outward from the rotational center of the impeller, the distance between the outer periphery of the impeller and the radially outer end of the inclined surface is the distance between the outer periphery of the impeller and the spiral or discharge ventilation path. The blower characterized by being in the range of 0.25 to 0.8 times the distance to the peripheral surface. A cylindrical impeller that allows air to flow in from an axial end and flow out of the outer periphery; and
A spiral air passage that is provided so as to surround the outer peripheral side of the impeller and that flows air that flows out of the outer peripheral portion of the impeller in the rotation direction of the impeller, and a discharge air that extends from the end portion of the spiral air passage toward the discharge port A casing formed with a path,
The casing includes a first side plate provided on one end side in the axial direction of the impeller, a second side plate provided on the other end side in the axial direction of the impeller and formed with a suction port, a start end portion of the spiral air passage, and a discharge A tongue that separates the ventilation path;
The second side plate is provided with an outer peripheral side of the impeller so as to extend along the circumferential direction of the impeller, and is provided with a protrusion that protrudes toward the first side plate side,
The protrusion is
Centering on the rotation axis of the impeller, it is provided between the protrusion start position and the tongue portion located within a range of 345 degrees or less from the start end portion of the spiral air passage toward the end portion,
The height gradually increases toward the tongue from the discharge start position to the maximum height,
In the axial direction of the impeller, the distance between the end portion on the second side plate side of the portion where the air of the impeller flows out and the portion having the maximum height is 0. 45 times or less,
On the outer peripheral side of the protrusion,
An inclined surface that gradually decreases in height toward the radially outer side is provided,
On the straight line extending radially outward from the rotational center of the impeller, the distance between the outer periphery of the impeller and the radially outer end of the inclined surface is the distance between the outer periphery of the impeller and the spiral or discharge ventilation path. A blower characterized by being in a range of 0.15 to 0.65 times the distance to the peripheral surface. The blower according to claim 1, wherein a flat portion extending in the circumferential direction at a maximum height is provided on a tongue portion side of the protrusion. A cylindrical impeller that allows air to flow in from an axial end and flow out of the outer periphery; and
A spiral air passage that is provided so as to surround the outer peripheral side of the impeller and that flows air that flows out of the outer peripheral portion of the impeller in the rotation direction of the impeller, and a discharge air that extends from the end portion of the spiral air passage toward the discharge port A casing formed with a path,
The casing includes a first side plate provided on one end side in the axial direction of the impeller, a second side plate provided on the other end side in the axial direction of the impeller and formed with a suction port, a start end portion of the spiral air passage, and a discharge A tongue that separates the ventilation path;
The first side plate and the second side plate are each provided with a protrusion that extends from a predetermined position on the outer peripheral side of the impeller toward the tongue portion along the circumferential direction of the impeller and protrudes into the spiral air passage. And
The protrusion has an inner side surface portion located on the radially inner side, an outer surface portion located on the radially outer side, and a distal end surface portion provided between the distal end portion of the inner side surface portion and the distal end portion of the outer surface portion,
The air blower characterized in that an interval between the inner side surface portion and the outer side surface portion decreases from the base end portion toward the tip end portion. The tip surface portion has a width that increases from a predetermined position on the outer peripheral side of the impeller toward the tongue,
The blower according to claim 4, wherein a width dimension of the tip surface portion near the tongue portion is substantially the same as a width dimension of the tongue portion. The protrusion has an extended outer surface extending from the outer surface toward the discharge port along the wall surface of the discharge ventilation path,
The blower according to claim 5, wherein the extended outer surface portion has a smaller amount of protrusion toward the discharge port. The projecting portion has an inner curved surface portion formed in a curved shape between the inner side surface portion and the distal end surface portion, and has an outer curved surface portion formed in a curved shape between the outer surface portion and the distal end surface portion,
The blower according to any one of claims 4 to 6, wherein a radius of curvature of the outer curved surface portion is larger than a curvature radius of the inner curved surface portion. The blower according to claim 7, wherein the inner curved surface portion and the outer curved surface portion each have a curvature radius that increases toward the tongue portion. The tip surface portion has a surface orthogonal to the axial direction of the impeller, or a surface inclined downward from the inner surface portion toward the outer surface portion. The blower described. The protrusion has an extended protrusion extending from the tongue to the start end side of the spiral air passage,
The extension protrusion is provided within a range of 120 degrees from the start end portion of the spiral air passage toward the end portion around the rotation axis of the impeller, and gradually protrudes toward the end portion of the spiral air passage. The blower according to claim 4, wherein the blower is smaller.

Images