JP2011226407A - Multi-blade fan, air conditioner, and guide member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-blade fan having superior fan efficiency and an air conditioner having the multi-blade fan.SOLUTION: A delivery port 19 of the multi-blade fan 10 is provided with a guide wall 35. The guide wall 35 has a main guide portion 31 extending in one direction from an edge of an outer pipe wall portion 433, and a pair of lateral guide portions 33 extending along the one direction from edges of a pair of pipe wall portions 412 and connected to both lateral ends of the main guide portion 31, respectively. An area facing the main guide portion 31 is open.

Description

  The present invention relates to a multiblade fan including a spiral casing, an air conditioner including the same, and a guide member that can be attached to a discharge port in the spiral casing of the multiblade fan.

  Conventionally, for example, a multiblade fan has been used as a blower of an air conditioner. The multiblade fan includes an impeller that is rotated by a fan motor and a spiral casing that houses the impeller. The spiral casing has a pair of side walls disposed on both sides in the axial direction of the impeller, and a peripheral wall (body plate) disposed between the pair of side walls. The pair of side walls respectively cover the side portions on both sides of the impeller, and the peripheral wall covers the periphery of the impeller along the rotation direction.

  In this multiblade fan, when the fan motor is driven and the impeller rotates, air is sucked into the spiral casing from the air suction port provided in the side wall. The air sucked into the spiral casing is sent into the impeller along the axial direction of the rotating shaft of the impeller, and further sent radially outward to pass through the gap between the blades. The air that has passed through this gap travels downstream in a spiral shape along the peripheral wall, and is blown out from the discharge port of the spiral casing (see, for example, Patent Document 1). The discharge port is an opening formed by a peripheral edge including a downstream edge of the peripheral wall and a downstream edge of the pair of side walls.

JP 2009-281198 A

  However, in the conventional multiblade fan disclosed in Patent Document 1, when air is blown out from the discharge port, the blown air entrains the surrounding air, resulting in energy loss (mixing loss). This mixing loss causes a decrease in fan efficiency. Moreover, since the air flow in the spiral casing and the air flow in the vicinity of the discharge port of the spiral casing are complicated, the flow of air blown from the discharge port tends to become unstable. This unstable air flow causes a decrease in fan efficiency.

  Therefore, the present invention has been made in view of such a point, and an object of the present invention is to provide a multiblade fan having excellent fan efficiency and an air conditioner including the same.

  The multiblade fan of the present invention has a plurality of blades arranged along the rotation direction (D) and is capable of rotating around a rotation axis (S), and the impeller (11). And a discharge pipe portion (172) that protrudes in one direction from the casing main body (171) and is provided with a discharge port (19) at the end and communicates with the casing main body (171). ) Having a spiral casing (17).

  The spiral casing (17) is formed between a pair of side plates (41) and a pair of side plates (41) disposed on both sides in the axial direction of the rotating shaft (S) of the impeller (11). And a trunk plate (43). The pair of side plates (41) includes a pair of side wall portions (411) that cover side portions on both sides in the axial direction of the rotating shaft (S) and constitute side walls on both sides of the casing body (171), and each side wall. A pair of tube wall portions (412) extending from the portion (411) in the one direction and constituting side walls on both sides of the discharge tube portion (172).

  The body plate (43) is disposed along the periphery of the impeller (11) between the pair of side wall portions (411), and constitutes a peripheral wall portion (431) constituting the peripheral wall of the casing body (171). And an inner tube wall portion (432) that extends in the one direction from a portion of the peripheral wall portion (431) on the proximal end side in the rotation direction (D) and constitutes an inner wall of the discharge pipe portion (172). ), And an outer tube wall portion (433) that extends in the one direction from the distal end portion in the rotation direction (D) of the peripheral wall portion (431) and constitutes an outer wall of the discharge pipe portion (172). ) And.

  The discharge port (19) includes an edge portion of the inner tube wall portion (432), an edge portion of the outer tube wall portion (433), and an edge portion of the discharge tube portion (172) in the one direction. It is formed by each edge part of a pair of pipe wall part (412).

  The discharge port (19) includes a main guide portion (31) extending along the one direction from the edge portion of the outer tube wall portion (433), and each edge portion of the pair of tube wall portions (412). A guide wall (35) having a pair of lateral guide portions (33) respectively extending along the one direction and connected to both ends in the width direction of the main guide portion (31) is provided. A region facing the main guide portion (31) is open.

  In general, in a multiblade fan having a spiral casing, air flows spirally between a peripheral wall and an impeller in the casing, so that the flow of air along the body plate located radially outward is particularly large. Prone to instability.

  Therefore, in the present configuration, the guide wall (35) is provided at the discharge port (19). The guide wall (35) plays a role of guiding the air blown from the discharge port through the spiral casing (17) along the body plate (43). Therefore, it is possible to prevent the air of an unstable flow immediately after flowing in the spiral casing (17) along the body plate (43) and blown out from the discharge port (19) from entraining the surrounding air. .

  Then, the air guided along the guide wall (35) is guided by the guide wall (35) and flows toward the discharge direction (downstream side) as compared with the case where the guide wall (35) is not provided. In the meantime, the flow stabilizes. When the flow is stabilized in this way, it passes through the downstream end of the guide wall (35) and mixes with the surrounding air, thus reducing energy loss due to the surrounding air being entrained. be able to.

  In addition, in this configuration, since the region facing the main guide portion (31) is open, there is no friction between the air and the wall surface in that region. Thereby, it can suppress that the energy loss by friction of the air which blown off from the discharge outlet (19) becomes large. From the above, according to this configuration, it is possible to provide a multiblade fan having excellent fan efficiency.

  In addition, when at least one of the main guide portion (31) and the lateral guide portion (33) extends so as to spread outward as it goes in the one direction, compared to a case where it does not extend so as to spread. Thus, the air blown from the discharge port can be blown out in a wider range.

  Moreover, it is preferable that at least one of the pair of lateral guide portions (33) is configured so that the width thereof is smaller than the width of the tube wall portion (412).

  In this configuration, the narrow lateral guide portion (33) is provided in the region on the main guide portion (31) side (the upper region in FIG. 1), but is opposite to the main guide portion (31). It is not provided in the side region (the lower region in FIG. 1). Accordingly, the lateral guide portion (33) having a small width serves to assist the air guiding function by the main guide portion (31) in the region on the main guide portion (31) side. On the other hand, since the lateral guide portion (33) having the small width is not provided in the region opposite to the main guide portion (31), the lateral guide portion (33) is connected to the tube wall portion (412). Compared with the case of extending to the one side with the same width, the friction between the wall surface of the lateral guide portion (33) and the air can be further reduced. Thereby, energy loss can be further suppressed.

  At least one of the pair of lateral guide portions (33) is configured such that a width at a distal end portion in the one direction is smaller than a width at a proximal end portion connected to the edge portion of the tube wall portion (412). It is preferable.

  In this configuration, the width of the lateral guide portion (33) is reduced in the downstream region where the air flow is relatively stabilized by the guide wall (35), that is, in the distal end portion side of the lateral guide portion (33). On the other hand, in the upstream region where the air flow is unstable, that is, in the proximal end portion side of the lateral guide portion (33), the width of the lateral guide portion (33) is made larger than that of the distal end portion. . As a result, the lateral guide portion (33) plays a role of assisting the air guiding function by the main guide portion (31) in the region on the proximal end side, while in the region on the distal end side, Friction between the wall surface of the guide portion (33) and air can be further reduced. Thereby, energy loss can be further suppressed.

  The air conditioner of the present invention is provided between a casing having an air outlet, the multi-blade fan accommodated in the casing, and the outlet and the discharge port (19) of the multi-blade fan. And a plenum chamber having a cross-sectional area parallel to the discharge port (19) in the space larger than the opening area of the discharge port (19).

  As in this configuration, the multiblade fan including the guide wall is suitable for an air conditioner including the plenum chamber. For example, when a duct having a passage similar to the opening cross section of the discharge port is directly attached to the discharge port of the multiblade fan, the duct itself serves to guide the air discharged from the discharge port. Fulfill. In this way, the duct is not directly attached to the discharge port of the multiblade fan, but the cross-sectional area of the space between the air outlet of the air conditioner and the discharge port of the multiblade fan is the opening area of the discharge port (19). In the case where a larger plenum chamber is provided, the above-described effect by the guide wall can be obtained. That is, since the air blown from the discharge port of the multiblade fan is guided by the guide wall in the plenum chamber, the air of an unstable flow immediately after being blown from the discharge port entrains the surrounding air. Can be suppressed.

  The guide member of the present invention can be attached to the substantially rectangular discharge port (19) in the spiral casing (17) of the multiblade fan. The guide member can be connected to one edge portion of the peripheral edge portion forming the discharge port (19), and has a plate-like main guide portion (31) extending along one direction, and the edge portion. A pair of lateral guide portions that can be connected to a pair of lateral edge portions located on both sides and extend in a direction substantially perpendicular to the main guide portion (31) from both ends in the width direction of the main guide portion (31) ( 33).

  In this configuration, the fan efficiency of the air conditioner can be improved by attaching the guide member to, for example, a multi-blade fan of an existing air conditioner.

  As described above, according to the present invention, it is possible to suppress a decrease in fan efficiency and to suppress the generation of noise.

(A) is a front view which shows the multiblade fan which concerns on 1st Embodiment of this invention, (B) is a top view of the said multiblade fan. It is the II-II sectional view taken on the line of FIG. (A) is a perspective view which shows the shape of the guide wall of the multiblade fan which concerns on 1st Embodiment, (B) is a perspective view which shows the modification, (C) is another modification. FIG. It is sectional drawing which shows an example of the air conditioning apparatus provided with the multiblade fan which concerns on 1st Embodiment. (A) is sectional drawing which shows the other example of the air conditioning apparatus provided with the multiblade fan which concerns on 1st Embodiment, (B) is the air conditioning provided with the multiblade fan which concerns on 1st Embodiment. It is sectional drawing which shows the further another example of an apparatus. (A) And (B) is a graph which shows the evaluation result which confirmed the effect of the guide wall of the multiblade fan which concerns on 1st Embodiment. It is a front view which shows the multiblade fan used for evaluation shown to the graph of FIG. It is a top view which shows the multiblade fan which concerns on 2nd Embodiment of this invention. (A) is a perspective view which shows the shape of the guide wall of the multiblade fan which concerns on 2nd Embodiment, (B) is a perspective view which shows the modification.

  Hereinafter, a multiblade fan according to an embodiment of the present invention will be described with reference to the drawings.

<First Embodiment>
As shown in FIGS. 1A, 1B, and 2, the multiblade fan 10 of this embodiment includes a spiral casing 17, an impeller 11 accommodated in the spiral casing 17, and the blades. And a motor 93 connected to the vehicle 11. In FIG. 2, the motor 93 is not shown.

  The spiral casing 17 includes a casing main body 171 that houses the impeller 11, and a discharge pipe portion 172 that protrudes from the casing main body 171 in the air discharge direction T. The discharge pipe portion 172 communicates with the casing body 171 and has a discharge port 19 at an end portion in the air discharge direction T. The spiral casing 17 includes a pair of side plates 41 disposed on the front F side and the back R side in the axial direction of the rotation axis S of the impeller 11, and a body plate 43 disposed between the side plates 41. And have.

  As shown in FIG. 1A, each side plate 41 has a side wall portion 411 and a tube wall portion 412. One side wall part 411 covers the side part on the front surface F side in the axial direction of the rotation axis S, and the other side wall part 411 covers the side part on the back surface R side. The pair of side wall portions 411 constitute side walls on both sides of the casing body 171. A pair of tube wall portions 412 located on both sides in the axial direction extend from each side wall portion 411 in the discharge direction T, and constitute side walls on both sides of the discharge tube portion 172.

  The body plate 43 has a peripheral wall portion 431, an inner tube wall portion 432, and an outer tube wall portion 433. The peripheral wall portion 431 is disposed along the periphery of the impeller 11 between the pair of side wall portions 411, and constitutes the peripheral wall of the casing body 171. The inner tube wall portion 432 extends in the discharge direction T from the proximal end side in the rotation direction D of the peripheral wall portion 431 and constitutes the inner wall of the discharge tube portion 172. The outer tube wall portion 433 extends in the discharge direction T from a portion on the distal end side in the rotation direction D of the peripheral wall portion 431, and constitutes an outer wall of the discharge tube portion 172.

  Therefore, the casing body 171 is configured by the side wall portions 411 of the side plates 41 and the peripheral wall portion 431 of the body plate 43. The discharge pipe part 172 includes a pipe wall part 412, an inner pipe wall part 432, and an outer pipe wall part 433 of each side plate 41. Further, the discharge port 19 is formed by an edge portion of the inner tube wall portion 432, an edge portion of the outer tube wall portion 433, and each edge portion of the pair of tube wall portions 412 at the end portion in the discharge direction T.

  As shown in FIGS. 1A, 1 </ b> B, and 2, the spiral casing 17 has a bell mouth 91 provided on the side plate 41 on the front F side. The bell mouth 91 is disposed opposite to the impeller 11 on the front F side. The bell mouth 91 has a substantially circular opening serving as a suction port for sucking air into the casing 17 and plays a role of guiding air to the impeller 11. As shown in FIG. 2, the inner peripheral surface 91 a of the bell mouth 91 has a curved shape whose inner diameter decreases from the front F side toward the back R side. Similarly, the outer peripheral surface 91b of the bell mouth 91 has a curved shape whose outer diameter decreases from the front F side toward the back R side.

  The impeller 11 includes a disk-shaped main plate 82 disposed to face the side wall portion 411 on the back surface R side, a plurality of forward blades 83 arranged along the rotation direction D, and a front surface F of these forward blades 83. And a ring portion 84 connected to the end portion on the side. The end on the back R side of each forward blade 83 is connected to the main plate 82. The length (chord length) from the front edge 83f to the rear edge 83r in each forward blade 83 is substantially constant in the axial direction of the rotation axis S. The main plate 82 includes a disk-shaped main plate main body 98 and a hub 97 protruding from the center of the main plate main body 98 to the front F side.

  The motor 93 is fixed to the side wall portion 411 on the rear surface R side of the spiral casing 17. A shaft 95 of the motor 93 is inserted into the casing body 171 through a not-shown through-hole provided in the side wall portion 411. The shaft 95 is fixed to the hub 97 of the impeller 11. In this way, the impeller 11 is supported by the spiral casing 17 so as to be rotatable about the rotation axis S thereof.

  When the impeller 11 is rotated by the motor 93, air is sucked into the casing 17 from the bell mouth 91 as shown by a two-dot chain line in FIG. The sucked air flows into the impeller 11 from the front F side in the axial direction of the rotating shaft S toward the rear R side along the axial direction, passes through the gap between the forward blades 83, and is radial. Outflow from the impeller 11 to the outside. The outflowed air moves inside the casing body 171 of the spiral casing 17 along the rotation direction D and is discharged from the discharge port 19 of the discharge pipe portion 172.

  A guide wall 35 is provided at the discharge port 19. The guide wall 35 extends from the edge of the outer tube wall portion 433 along the discharge direction T, and extends from each edge of the pair of tube wall portions 412 along the discharge direction T. And a pair of lateral guide portions 33 respectively connected to both end portions of the portion 31 in the width direction.

  As shown in FIGS. 1 (A) and 3 (A), the main guide portion 31 of the guide wall 35 in this embodiment has substantially the same width as the outer tube wall portion 433 and is discharged substantially parallel to the outer tube wall portion 433. It has a substantially rectangular shape extending in the direction T.

  Each lateral guide portion 33 of the guide wall 35 has a substantially rectangular shape extending in the discharge direction T substantially parallel to the tube wall portion 412. Each lateral guide portion 33 has a width B smaller than the width D of the edge portion of the tube wall portion 412 from the base end portion 33b connected to the edge portion of the tube wall portion 412 to the entire distal end portion 33b in the discharge direction T, and is constant. is there.

  Each dimension of each lateral guide portion 33 is not particularly limited, but the ratio (B / D) is as shown in the evaluation results of FIGS. 6 (A) and 6 (B) described later. The ratio is preferably in the range of 0.06 to 0.48, and the ratio (A / C) is preferably in the range of 0.15 to 0.60.

  A region facing the main guide portion 31, that is, a lower portion of the main guide portion 31 in FIG. Therefore, among the air discharged from the discharge port 19, the air discharged from the region on the inner tube wall 432 side is forward (discharge direction T), downward, side as indicated by arrows in FIG. It spreads to the people and proceeds. On the other hand, the air discharged from the region on the outer tube wall 433 side is guided by the guide wall 35 and proceeds along the discharge direction T.

  The guide wall 35 is obtained, for example, by bending a sheet metal. The guide wall 35 may be manufactured separately from the discharge pipe portion 172 of the spiral casing 17 and then attached to the discharge port 19 or may be integrally formed with the discharge pipe portion 172. The guide wall 35 can be retrofitted as a guide member 35 to a multi-blade fan of an existing air conditioner. In order to attach the guide wall 35 to the discharge pipe portion 172, various methods such as screwing, welding, brazing, and the like can be used.

  FIG. 3B is a perspective view showing a modification of the multiblade fan 10 in FIG. 3A, and FIG. 3C is a perspective view showing another modification. As shown in FIGS. 3B and 3C, each of the lateral guide portions 33 of the multiblade fan 10 has a width B at the distal end portion 33b in the discharge direction T at the edge of the tube wall portion 412. It is smaller than the width B at the connected proximal end portion 33b.

  Each of these lateral guide portions 33 has a width B that gradually decreases from the proximal end portion 33a toward the distal end portion 33b. The lower side of the lateral guide portion 33 in FIG. 3B is curved in an arcuate shape. On the other hand, the lateral guide portion 33 in FIG. 3C has a substantially triangular shape in a side view.

  FIG. 4 is a cross-sectional view illustrating an example of the indoor unit 71 of the air conditioner including the multiblade fan 10 according to the first embodiment. As shown in FIG. 4, the indoor unit 71 is of a type having a vertically long shape that is arranged on an indoor floor, for example. In the indoor unit 71, the heat exchanger 76 and the multiblade fan 10 are accommodated in a substantially rectangular parallelepiped casing 72.

  The casing 72 has a suction port 73 for sucking air into the casing 72 on the lower front surface, and a blower outlet 77 for blowing the air in the casing 72 to the outside on the front surface of the upper portion. A grill 74 is attached to the suction port 73, and a filter 75 is disposed along the grill 74 inside the grill 74. A plurality of flaps 78 that are rotatably supported on a rotation shaft (not shown) are disposed at the air outlet 77. The air blowing direction can be adjusted by rotating these flaps 78.

  The inside of the casing 72 is divided into two upper and lower spaces 80 and 81 by a partition plate 79. A suction port 73 is provided in a lower space 80 inside the casing 72, and the heat exchanger 76 and the spiral casing 17 of the multiblade fan 10 are disposed. The heat exchanger 76 is disposed below the multiblade fan 10. The upper space (plenum chamber) 81 is provided with an air outlet 77, and the guide wall 35 of the multiblade fan 10 is disposed.

  The partition plate 79 is a plate-like member that is located in the upper part of the internal space of the casing 72 and is arranged in a substantially horizontal direction in the vicinity of the lower end of the air outlet 77. A through-hole is provided in a region on the back side of the partition plate 79, and the end of the discharge pipe portion 172 of the multiblade fan 10 is disposed in the through-hole.

  The plenum chamber 81 is a space provided between the air outlet 77 and the discharge port 19 of the multiblade fan 10. As shown in FIG. 4, the area of the cross section parallel to the discharge port 19 in the space of the plenum chamber 81 is larger than the opening area of the discharge port 19.

  In the air conditioner 71, when the motor 93 is driven to rotate the impeller 11, air is sucked into the casing 72 from the suction port 73, passes through the heat exchanger 76, and reaches the bell mouth 91 of the multiblade fan 10. And is sucked into the spiral casing 17. The air sucked into the spiral casing 17 advances spirally in the spiral casing 17 and is discharged from the discharge port 19 to the plenum chamber 81. In the plenum chamber 81, the air is made uniform to some extent in the plenum chamber 81 and then blown into the room from the outlet 77.

  FIG. 5A is a cross-sectional view illustrating another example of the indoor unit 71 of the air conditioner including the multiblade fan according to the first embodiment. As shown in FIG. 5A, the indoor unit 71 is a built-in ceiling-embedded indoor unit that is used by being embedded in a ceiling. In the indoor unit 71, the heat exchanger 76 and the multiblade fan 10 are accommodated in a substantially rectangular parallelepiped casing 72.

  The casing 72 has a suction port 73 for sucking air into the casing 72 on the lower surface of the rear part, and has a blower outlet 77 for blowing the air in the casing 72 to the outside on the front surface of the front part. A grill 74 is attached to the suction port 73, and a filter 75 is disposed along the grill 74 inside the grill 74. A duct 70 is connected to the air outlet 77.

  The inside of the casing 72 is divided into two front and rear spaces 80 and 81 by a partition plate 79. A suction space 73 is provided in a space 80 behind the casing 72, and the spiral casing 17 of the multiblade fan 10 is disposed. The front space (plenum chamber) 81 is provided with an air outlet 77, the guide wall 35 of the multiblade fan 10 is disposed, and the heat exchanger 76 is disposed. The heat exchanger 76 is disposed between the discharge port 19 and the guide wall 35 of the multiblade fan 10 and the air outlet 77. The multi-blade fan 10 of the indoor unit 71 communicates with the duct 70 via the plenum chamber 81.

  The partition plate 79 is a plate-like member that is positioned in the vicinity of the center in the front-rear direction in the internal space of the casing 72 and that is disposed in a substantially vertical direction near the front end of the suction port 73. A through hole is provided in the upper region of the partition plate 79, and the end of the discharge pipe portion 172 of the multiblade fan 10 is disposed in the through hole.

  The plenum chamber 81 is a space provided between the air outlet 77 and the discharge port 19 of the multiblade fan 10. As shown in FIG. 5A, the area of the cross section parallel to the discharge port 19 in the space of the plenum chamber 81 is larger than the opening area of the discharge port 19.

  In the air conditioner 71, when the motor 93 is driven to rotate the impeller 11, air is sucked into the casing 72 from the suction port 73 and enters the spiral casing 17 along the bell mouth 91 of the multiblade fan 10. Inhaled. The air sucked into the spiral casing 17 advances spirally in the spiral casing 17 and is discharged from the discharge port 19 to the plenum chamber 81. The air discharged into the plenum chamber 81 passes through the heat exchanger 76 and is sent to the duct 70 through the air outlet 77.

  FIG. 5B is a cross-sectional view showing still another example of the indoor unit 71 of the air conditioner including the multiblade fan according to the first embodiment. As shown in FIG. 5B, the indoor unit 71 is a ceiling-suspended indoor unit. About this indoor unit 71, a difference with FIG. 5 (A) is demonstrated, about the other site | part, the same code | symbol as FIG. 5 (A) is attached | subjected, and the description is abbreviate | omitted.

  The indoor unit 71 in FIG. 5B is different from the indoor unit 71 in FIG. 5A in that it is not connected to the duct 70 like the indoor unit 71 in FIG. In the indoor unit 71, air is blown directly into the room from the air outlet 77.

  In addition, the partition plate 79 of the indoor unit 71 in FIG. 5B has an upper partition portion 79a and a lower partition portion 79b because the blowing direction of the multi-blade fan 10 is slightly inclined with respect to the horizontal direction. There is a step between them. With this partition plate 79, the inside of the casing 72 is divided into two spaces 80 and 81 in the front and rear directions. It arrange | positions so that the edge part of the discharge pipe part 172 of the multiblade fan 10 may fit in the through-hole provided in the partition plate 79. FIG.

  The plenum chamber 81 is a space provided between the air outlet 77 and the discharge port 19 of the multiblade fan 10. As shown in FIG. 5B, the area of the cross section parallel to the discharge port 19 in the space of the plenum chamber 81 is larger than the opening area of the discharge port 19.

  Next, the evaluation result of the multiblade fan 10 of 1st Embodiment is demonstrated.

  6A and 6B are graphs comparing the fan efficiencies of the multiblade fan 10 according to this embodiment and the conventional multiblade fan. The data of these graphs are obtained by actually operating the multi-blade fan 10 of the present embodiment and the conventional multi-blade fan, measuring the fan efficiency at that time, and using the fan efficiency of the conventional multi-blade fan as a reference (zero). The fan efficiency of the multi-blade fan 10 of the present embodiment is shown. Therefore, when the data is positive, it indicates that the fan efficiency of the multiblade fan 10 of the present embodiment is higher than the fan efficiency of the conventional multiblade fan.

  The data shown in FIG. 6A is a comparison between the fan efficiency of the multiblade fan 10 and the fan efficiency of a conventional multiblade fan that does not have the guide wall 35. These data include the width B of the lateral guide portion 33 of the guide wall 35 of the multiblade fan 10 shown in FIG. 7 (the width of the base end portion of the lateral guide portion 33 connected to the discharge port 19), and the discharge port 19. The ratio (B / D) with the edge length D of the tube wall portion 412 to be formed was changed from zero to 0.48 and measured (the length D was set to a constant value of 97 mm, and the width B was changed. ). In addition, the case where the ratio (B / D) is zero is a form in which a guide wall including only the main guide portion 31 without the lateral guide portion 33 is attached to the discharge port 19.

  When measuring the data shown in FIG. 6A, the value of the ratio (A / C) was 0.6. The dimension A is the length of the guide wall 35 in the discharge direction T. The dimension C is a distance between the discharge port 19 and a straight line L that is perpendicular to the outer surface of the main guide portion 31 of the guide wall 35 and passes through the rotation axis S. This dimension C was 160 mm. The casing body 171 of the spiral casing 17 has a dimension in the direction parallel to the straight line L of 278 mm, a dimension in the direction perpendicular to the straight line L of 247 mm, and a dimension (depth) in the axial direction of the rotating shaft S of 75 mm. did.

  The multiblade fan 10 shown in FIG. 7 used for this data measurement is slightly different from the multiblade fan 10 shown in FIG. 1 in the shape of the discharge pipe portion 172. That is, in the discharge pipe portion 172 of the multiblade fan 10 shown in FIG. 7, the portion on the casing body 171 side is inclined downward in FIG. 7 with respect to the extending direction of the guide wall 35 (discharge direction T). The vicinity of the distal end portion of the discharge pipe portion 172 on the discharge port 19 side extends substantially in parallel with the extending direction of the guide wall 35 (discharge direction T). The length of the parallel extending portion was 20 mm as shown in FIG.

  The fan efficiency ηt of the multiblade fan is obtained by multiplying the air volume Q by the total pressure Pt and dividing by the shaft power L (fan efficiency ηt = (air volume Q × total pressure Pt) ÷ shaft power L). The total pressure Pt is a value obtained by adding the static pressure Ps and the dynamic pressure Pv of the discharge port (total pressure Pt = static pressure Ps + dynamic pressure Pv of the discharge port).

  As shown in FIG. 6 (A), the fan efficiency when the guide wall is composed only of the main guide portion 31 and no lateral guide portion 33, that is, the ratio (B / D) is zero, is the conventional fan efficiency without the guide wall. It is almost the same as a multi-blade fan, and it can be seen that the effect of improving fan efficiency is not obtained. On the other hand, the multi-blade fan 10 having the main guide portion 31 and the lateral guide portion 33 is superior in fan efficiency compared to the conventional multi-blade fan and the multi-blade fan in which the ratio (B / D) is zero. It can be seen that the fan efficiency is improved as the width B of the lateral guide portion 33 is increased. Although not shown in FIG. 6A, the fan efficiency when the ratio (B / D) is larger than 0.48 is the fan efficiency when the ratio (B / D) is 0.48. It was almost the same level.

  The data shown in FIG. 6B is a comparison between the fan efficiency of the multiblade fan 10 and the fan efficiency of a conventional multiblade fan that does not have the guide wall 35. These data show that the ratio (A / C) between the dimension A in the ejection direction T of the guide wall 35 shown in FIG. 7 and the dimension C from the ejection port 19 to the straight line L is between 0.15 and 0.60. Measured by changing. When measuring the data shown in FIG. 6B, the ratio (B / D) was set to 0.48.

  As shown in FIG. 6B, the multi-blade fan 10 having the main guide portion 31 and the lateral guide portion 33 is superior in fan efficiency as compared with a conventional multi-blade fan having no guide wall. It can be seen that the fan efficiency improves as the value increases. Although not shown in FIG. 6B, the fan efficiency when the ratio (A / C) is larger than 0.60 is the fan efficiency when the ratio (A / C) is 0.60. It was almost the same level.

  As described above, in this embodiment, the guide wall 35 is provided at the discharge port 19. The guide wall 35 plays a role of guiding the air blown from the discharge port by flowing along the body plate 43 in the spiral casing 17. Therefore, it is possible to prevent the air of an unstable flow immediately after flowing in the spiral casing 17 along the body plate 43 and blown out from the discharge port 19 from entraining the surrounding air. Then, the air guided along the guide wall 35 is more stable while being guided by the guide wall 35 and flowing in the discharge direction T (downstream side) than when the guide wall 35 is not provided. Turn into. When the flow is stabilized in this way, it passes through the end portion on the downstream side of the guide wall 35 and is mixed with the surrounding air, so that it is possible to reduce energy loss caused by the surrounding air being entrained. it can. Moreover, since it can suppress that the air of an unstable flow mixes with the surrounding air, the effect of reducing a noise level can also be anticipated. In addition, when the dimension of the discharge pipe portion 172 in the discharge direction T is short, the air flow tends to become particularly unstable, and thus the above-described effect by providing the guide wall 35 is high.

  In addition, in the present embodiment, since the region facing the main guide portion 31 is open, there is no friction between the air and the wall surface in that region. Thereby, it is possible to suppress an increase in energy loss due to friction of air blown from the discharge port 19.

  In the present embodiment, the pair of lateral guide portions 33 is configured such that each width is smaller than the width of the tube wall portion 412. That is, each lateral guide portion 33 is provided in a region on the main guide portion 31 side, but is not provided in a region on the opposite side to the main guide portion 31. Accordingly, each lateral guide portion 33 plays a role of assisting the air guiding function by the main guide portion 31 in the region on the main guide portion 31 side. On the other hand, since each lateral guide portion 33 is not provided in a region opposite to the main guide portion 31, each lateral guide portion 33 has the same width as the tube wall portion 412 and extends in the discharge direction T. Compared to the case, the friction between the wall surface of each lateral guide portion 33 and the air can be further reduced. Thereby, energy loss can be further suppressed.

  In the modification of the present embodiment, the pair of lateral guide portions 33 has a width at the distal end portion 33b in the discharge direction T that is smaller than a width at the proximal end portion 33a connected to the edge of the tube wall portion 412. It is configured. That is, in this modified example, in the downstream region where the air flow is relatively stabilized by the guide wall 35 (region on the tip 33b side of each lateral guide portion 33), the width of each lateral guide portion 33 is increased. On the other hand, in the upstream region (region on the base end portion 33a side of each lateral guide portion 33) where the air flow is unstable, the width of each lateral guide portion 33 is made larger than that of the distal end portion 33b. It is getting bigger.

  Thereby, each lateral guide portion 33 plays a role of assisting the air guiding function by the main guide portion 31 in the region on the base end portion 33a side, while each lateral guide portion 33 in the region on the distal end portion 33b side. The friction between the wall surface of the guide portion 33 and the air can be further reduced. Therefore, energy loss can be further suppressed.

Second Embodiment
FIG. 8 is a plan view showing the multiblade fan 10 according to the second embodiment of the present invention, and FIG. 9A is a perspective view showing the shape of the guide wall 35 of the multiblade fan 10. In addition, the same code | symbol is attached | subjected to the same component as 1st Embodiment here, and the detailed description is abbreviate | omitted.

  The multi-blade fan 10 of the second embodiment is different from the first embodiment in that each lateral guide portion 33 extends so as to spread outward as it goes in the discharge direction T. In this 2nd Embodiment, compared with the case where the horizontal guide part 33 is not extended so that it may spread outside, the air which blows off from the discharge outlet 19 can be blown out more widely. The lateral guide portion 33 may be flat or curved.

  FIG. 9B is a perspective view showing a modification of the shape of the guide wall 35 of the multiblade fan 10 according to the second embodiment. As shown in FIG. 9B, each lateral guide portion 33 of the multiblade fan 10 has a width at the distal end portion 33b in the discharge direction T that is larger than a width at the proximal end portion 33b connected to the edge portion of the tube wall portion 412. Is also small.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to each said embodiment, A various change, improvement, etc. are possible in the range which does not deviate from the meaning.

  For example, in the above-described embodiment, the case where the lateral guide portion 33 extends so as to spread outward as it goes in the discharge direction T has been illustrated, but the main guide portion 31 extends so as to spread outward as it goes in the discharge direction T. May be.

  Moreover, although the said embodiment illustrated the case where the width | variety B of each horizontal guide part 33 was smaller than the width | variety of the pipe wall part 412, it is not limited to this. For example, the width B of one lateral guide portion 33 may be smaller than the width of the tube wall portion 412, and the width B of the other lateral guide portion 33 may be the same width as the tube wall portion 412. Further, the width B of both the lateral guide portions 33 may be the same width as the tube wall portion 412.

DESCRIPTION OF SYMBOLS 10 Multiblade fan 11 Impeller 17 Spiral-shaped casing 171 Casing main body 172 Discharge pipe part 19 Discharge port 41 Side plate 411 Side wall part 412 Tube wall part 43 Body plate 431 Circumferential wall part 432 Inner pipe wall part 433 Outer pipe wall part 83 Forward blade | wing 83f Front edge of forward blade 83r Rear edge of forward blade D Rotating direction F Front side in the axial direction of the rotating shaft R Back side in the axial direction of the rotating shaft S Rotating shaft

Claims (9)

An impeller (11) having a plurality of blades arranged along the rotation direction (D) and rotatable about the rotation shaft (S), and a casing body (171) for housing the impeller (11) And a spiral casing (17) having a discharge port (19) projecting in one direction from the casing body (171) and having a discharge port (19) at its end and communicating with the casing body (171). ), And a multi-wing fan,
The spiral casing (17) is formed between a pair of side plates (41) and a pair of side plates (41) disposed on both sides in the axial direction of the rotating shaft (S) of the impeller (11). A body plate (43) disposed on the
The pair of side plates (41) includes a pair of side wall portions (411) that cover side portions on both sides in the axial direction of the rotating shaft (S) and constitute side walls on both sides of the casing body (171), and each side wall. A pair of tube wall portions (412) extending in one direction from the portion (411) and constituting side walls on both sides of the discharge tube portion (172),
The body plate (43) is disposed along the periphery of the impeller (11) between the pair of side wall portions (411), and constitutes a peripheral wall portion (431) constituting the peripheral wall of the casing body (171). And an inner tube wall portion (432) that extends in the one direction from a portion of the peripheral wall portion (431) on the proximal end side in the rotation direction (D) and constitutes an inner wall of the discharge pipe portion (172). ), And an outer tube wall portion (433) that extends in the one direction from the distal end portion in the rotation direction (D) of the peripheral wall portion (431) and constitutes an outer wall of the discharge pipe portion (172). ) And
The discharge port (19) includes an edge portion of the inner tube wall portion (432), an edge portion of the outer tube wall portion (433), and an edge portion of the discharge tube portion (172) in the one direction. Formed by each edge of the pair of tube wall portions (412),
The discharge port (19) includes a main guide portion (31) extending along the one direction from the edge portion of the outer tube wall portion (433), and each edge portion of the pair of tube wall portions (412). A guide wall (35) having a pair of lateral guide portions (33) respectively extending from one side to the other in the width direction of the main guide portion (31).
A multiblade fan in which a region facing the main guide portion (31) is open.   2. The multiblade fan according to claim 1, wherein at least one of the main guide portion (31) and the lateral guide portion (33) extends so as to spread outward in the one direction.   The multiblade fan according to claim 1 or 2, wherein the width of at least one of the pair of lateral guide portions (33) is smaller than the width of the tube wall portion (412).   At least one of the pair of lateral guide portions (33) has a width at a distal end portion in the one direction smaller than a width at a proximal end portion connected to the edge portion of the tube wall portion (412). The multiblade fan of any one of -3. A casing having an air outlet;
The multiblade fan according to any one of claims 1 to 4, housed in the casing,
A space provided between the air outlet and the discharge port (19) of the multiblade fan, and an area of a cross section parallel to the discharge port (19) in the space is an opening of the discharge port (19). An air conditioner having a plenum chamber larger than the area. A guide member attachable to a substantially rectangular discharge port (19) in a spiral casing (17) of a multiblade fan,
A plate-shaped main guide portion (31) connectable to one edge portion of the peripheral edge portion forming the discharge port (19), and extending along one direction;
A pair of lateral edges that can be connected to both sides of the edge, and a pair extending from both ends in the width direction of the main guide (31) in a direction substantially orthogonal to the main guide (31) A guide member having a lateral guide portion (33).   The guide member according to claim 6, wherein at least one of the main guide portion (31) and the lateral guide portion (33) extends so as to spread outward as it goes in the one direction.   The guide member according to claim 6 or 7, wherein at least one of the pair of lateral guide portions (33) has a width smaller than a length of the lateral edge portion. At least one of the pair of lateral guide portions (33) has a width at a distal end portion in the one direction smaller than a width at a proximal end portion connected to the lateral edge portion. The guide member according to Item 1.

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