JP5353994B2 - Axial fan - Google Patents

Description

  The present invention relates to an axial flow fan, and more particularly to an axial flow fan in which a hub and a plurality of blades formed so as to protrude from the outer peripheral edge of the hub are integrally molded with resin.

  Conventionally, in an outdoor unit or the like of an air conditioner, an axial fan in which a hub and a plurality of blades formed so as to protrude from the outer peripheral edge of the hub are integrally formed with resin has been used.

  As such an axial fan, there is a fan in which a meat stealing portion is formed at the base of the blade hub as shown in Patent Document 1 (Japanese Patent Laid-Open No. 2011-74817).

  However, forming the meat stealing portion at the base portion of the blade leads to narrowing the space in which the resin injected into the mold flows toward the outer peripheral side when the axial flow fan is formed. For this reason, in the axial fan in which the meat stealing portion is formed at the base of the blade, it is difficult for the resin to flow into the outer peripheral portion of the meat stealing portion at the time of molding, and there is a risk that molding failure may occur in the outer peripheral portion of the blade. is there.

  SUMMARY OF THE INVENTION An object of the present invention is to form a meat stealing portion at the base of a blade in an axial fan in which a hub and a plurality of blades are integrally molded with a resin while suppressing molding defects at the outer peripheral portion of the blade.

  The axial fan according to the first aspect is one in which a hub and a plurality of blades formed so as to protrude from the outer peripheral edge of the hub are integrally molded with resin. And the 1st blade meat stealing part is formed in the base part with the hub of a blade | wing so that the radial rib extended radially toward the outer peripheral side may remain.

  The inventor of the present application, when forming the meat stealing portion at the base of the blade, is left when the meat stealing portion is formed in consideration of the flow of the resin during molding to the outer peripheral portion of the meat stealing portion. The shape of the rib was studied. As a result, the inventors of the present application have found that the first blade meat stealing portion is formed so that the radial ribs extending radially toward the outer peripheral side are left as described above.

  Such radial ribs facilitate the flow of the resin injected into the mold at the time of molding toward the outer peripheral side, so that the resin can flow into the outer peripheral portion more than the first blade meat stealing portion at the time of molding. Can be made. In addition, the radial ribs make it easier for the resin injected into the mold to flow toward the outer peripheral side than when the ribs that do not extend radially are left.

  Thereby, in this axial flow fan, the meat stealing portion can be formed at the base portion of the blade while suppressing the molding failure in the outer peripheral portion of the blade.

Further, in this axial fan, a front edge rib that is continuous with the front edge of the blade, a portion of the root portion on the front edge side of the blade with respect to the radial rib is formed. A second blade meat stealing portion larger than the first blade meat stealing portion is formed between the circumferential directions of the leading edge rib and the radial rib.

As described above, in this axial fan, the strength at the leading edge of the blade is improved by forming the leading edge rib continuous to the leading edge of the blade at the portion of the leading edge side of the blade from the radial rib. . However, if such a leading edge rib is formed, the leading edge rib and its vicinity may be difficult to be cooled during molding.

Therefore, in this axial fan, as described above, the front edge rib is formed, and the second blade meat stealing portion larger than the first blade meat stealing portion is formed between the front edge rib and the radial rib in the circumferential direction. Thus, the leading edge rib and its vicinity are prevented from becoming difficult to be cooled during molding.

Thereby, in this axial fan, although not only the radial rib but also the leading edge rib is formed, the occurrence of sink marks during molding can be suppressed.

  The axial fan according to the second aspect is the axial fan according to the first aspect, in which a plurality of radial ribs are arranged in the circumferential direction.

  As described above, when a plurality of radial ribs are arranged in the circumferential direction, it is possible to increase in the circumferential direction the portion where the resin flows to the outer peripheral side of the first blade meat stealing portion during molding.

  Thereby, in this axial fan, it can further accelerate | stimulate that the resin inject | poured into a metal mold | die flows toward the outer peripheral side at the time of shaping | molding. Further, at the time of molding, the resin can easily flow evenly at any circumferential position of the portion on the outer peripheral side of the first blade meat stealing portion.

  The axial fan according to the third aspect is the axial fan according to the first or second aspect, wherein the radial ribs are directed from the hub axis toward the outer peripheral side when the hub and the blades are viewed from the axial direction. It extends on a straight line extending radially.

  As described above, if the radial ribs extend on a straight line extending radially from the hub axis toward the outer peripheral side, the resin injected into the mold during molding flows straight toward the outer peripheral side. .

  Thereby, in this axial fan, at the time of molding, the resin injected into the mold can be further flowed toward the outer peripheral side.

The axial fan according to the fourth aspect is the axial fan according to the second or third aspect , in which radial ribs are arranged at equal intervals in the circumferential direction.

  As described above, when the radial ribs are arranged at equal intervals in the circumferential direction, the resin can easily flow into the plurality of radial ribs at the time of molding.

  Thereby, in this axial flow fan, at the time of molding, the resin can more easily flow in the circumferential direction into the portion on the outer peripheral side than the first blade meat stealing portion.

In the axial fan according to the fifth aspect , in any one of the first to fourth aspects , a recessed portion that is recessed toward the front edge side of the blade is formed at the rear edge of the blade. And the 1st blade meat stealing part is located in the front edge side of a wing | blade rather than a recessed part, when a hub and a blade | wing are seen from an axial direction.

  As described above, in this axial flow fan, at the trailing edge of the blade, a recessed portion that is recessed toward the front edge side of the blade is formed, thereby improving the blowing performance and suppressing noise. However, if such a dent is formed, the resin is less likely to flow into the dent and its vicinity during molding, and there is a possibility that a molding defect in the dent and its vicinity may occur.

  Therefore, in this axial fan, as described above, the first blade meat stealing portion is positioned on the front edge side of the blade with respect to the recess portion, and at the time of molding, the resin passes through the first blade meat stealing portion. It flows into the dent part and the vicinity thereof without any problems.

  Thereby, in this axial flow fan, although both the first blade meat stealing part and the dent part are formed, the inflow of the resin to the dent part at the time of molding and the vicinity thereof is secured, and the dent part And the molding defect of the vicinity can be suppressed.

  As described above, according to the present invention, the following effects can be obtained.

In the axial fan according to the first aspect, the meat stealing portion can be formed at the base portion of the blade while suppressing the molding failure in the outer peripheral portion of the blade. Moreover, although not only the radial ribs but also the leading edge ribs are formed, the occurrence of sink marks during molding can be suppressed.

  In the axial fan according to the second aspect, the resin injected into the mold can be further promoted to flow toward the outer peripheral side during molding. Further, at the time of molding, the resin can easily flow evenly at any circumferential position of the portion on the outer peripheral side of the first blade meat stealing portion.

  In the axial fan according to the third aspect, at the time of molding, the resin injected into the mold can be further flowed toward the outer peripheral side.

In the axial fan according to the fourth aspect , at the time of molding, the resin can flow more evenly in the circumferential direction into the portion on the outer peripheral side than the first blade meat stealing portion.

In the axial fan according to the fifth aspect , despite the formation of both the first blade meat stealing part and the dent part, ensuring the inflow of the resin to the dent part and its vicinity during molding, It is possible to suppress molding defects in the recessed portion and the vicinity thereof.

It is a top view which shows the state which removed the top plate of the outdoor unit as which the outdoor fan as an axial fan concerning one Embodiment of this invention was employ | adopted. It is a front view of the outdoor unit by which the outdoor fan concerning one Embodiment of this invention was employ | adopted. It is a perspective view of the outdoor fan concerning one embodiment of the present invention. It is a positive pressure surface side top view of an outdoor fan concerning one embodiment of the present invention. It is a negative surface side top view of the outdoor fan concerning one embodiment of the present invention. It is a side view of the outdoor fan concerning one embodiment of the present invention. FIG. 6 is an enlarged view of a base portion of the blade of FIG. 5 and its vicinity. It is II sectional drawing of FIG. FIG. 7 is an enlarged view of the front edge rib of FIG. 6 and its vicinity. It is side surface sectional drawing of the metal mold | die for demonstrating the formation process of an outdoor fan. It is sectional drawing which shows the part which forms the root part of the blade | wing of a metal mold | die for demonstrating the formation process of an outdoor fan, and its vicinity.

  Hereinafter, an embodiment of an axial fan according to the present invention will be described with reference to the drawings. In addition, the specific structure of the axial fan concerning this invention is not restricted to the following embodiment, It can change in the range which does not deviate from the summary of invention. In the following description, an example in which the present invention is applied to an axial fan constituting an outdoor unit will be described. However, the present invention is not limited to this and can be applied to an axial fan used for other purposes. It is.

(1) Overall Configuration of Outdoor Unit FIGS. 1 and 2 are views showing an outdoor unit 2 of an air conditioner that employs an outdoor fan 70 as an axial fan according to an embodiment of the present invention. Here, FIG. 1 is a plan view showing a state in which the top plate 57 of the outdoor unit 2 is removed. FIG. 2 is a front view of the outdoor unit 2. In the following explanation, directions and surfaces such as “top”, “bottom”, “left”, “right”, “front”, “side”, “back”, “top”, “bottom” are shown. The wording means a direction and a surface when the outdoor unit 2 shown in FIG.

  The outdoor unit 2 has a structure (so-called trunk type structure) in which the blower chamber S1 and the machine chamber S2 are formed by dividing the internal space of the unit casing 51 into left and right by a partition plate 58 extending in the vertical direction. . The outdoor unit 2 is configured to suck outdoor air into the unit casing 51 from a part of the back surface and side surface of the unit casing 51 and blow out outdoor air from the front surface of the unit casing 51. The outdoor unit 2 mainly includes a unit casing 51, a compressor 21, an outdoor heat exchanger 24, refrigerant circuit components including refrigerant pipes connecting these devices, an outdoor fan 70 (axial fan), And a bell mouth 80. Here, an example in which the blower chamber S1 is formed near the left side surface of the unit casing 51 and the machine chamber S2 is formed near the right side surface of the unit casing 51 will be described, but the left and right sides may be reversed.

  The unit casing 51 is formed in a substantially rectangular parallelepiped shape, and mainly accommodates the compressor 21, the outdoor heat exchanger 24, refrigerant circuit components including refrigerant pipes connecting these devices, and the outdoor fan 70. doing. The unit casing 51 includes a bottom plate 52, a blower chamber side plate 53, a machine chamber side plate 54, a blower chamber side front plate 55, a machine chamber side front plate 56, and a top plate 57.

  The bottom plate 52 is a metal plate member that constitutes the bottom surface portion of the unit casing 51. Below the bottom plate 52, two foundation legs 59 and 60 fixed to the field installation surface are provided.

  The blower chamber side plate 53 is a metal plate-like member that constitutes a side surface portion of the unit casing 51 near the blower chamber S1. The lower part of the blower chamber side plate 53 is fixed to the bottom plate 52. The blower room side plate 53 is formed with an outdoor air suction port 53 a that is sucked into the unit casing 51 by the outdoor fan 70.

  The machine room side plate 54 is a metal plate-like member that constitutes a part of a side surface portion of the unit casing 51 near the machine room S2 and a back surface portion of the unit casing 51 near the machine room S2. The lower part of the machine room side plate 54 is fixed to the bottom plate 52. Here, the machine room side plate 54 covers a portion closer to the back surface of the side surface of the machine room S2. Between the rear side end of the blower chamber side plate 53 and the end of the machine chamber side plate 54 on the blower chamber S1 side, an outdoor air suction port 53b that is sucked into the unit casing 51 by the outdoor fan 70 is formed. Has been.

  The blower chamber side front plate 55 is a metal plate-like member that constitutes the front portion of the blower chamber S1 of the unit casing 51 and a part of the front portion of the machine chamber S2 of the unit casing 51. The blower chamber side front plate 55 is provided with an outlet 55 a for blowing outdoor air sucked into the unit casing 51 by the outdoor fan 70. The front side of the outlet 55a is covered with a fan grill 55b. The lower portion of the blower chamber side front plate 55 is fixed to the bottom plate 52, and the left end portion thereof is fixed to the front end portion of the blower chamber side plate 53.

  The machine room side front plate 56 is a metal plate that is removed during a trial run or maintenance in order to access the machine room S2 from the front side of the unit casing 51 and inspect the equipment disposed in the machine room S2. It is a member. The machine room side front plate 56 is a metal plate-like member that constitutes a part of the front part of the machine room S2 of the unit casing 51 and a part of the side part of the machine room S2 of the unit casing 51. The machine room side front plate 56 has an end on the fan chamber S1 side fixed to an end on the machine room S2 side of the fan room side front plate 55, and an end on the back side of the machine room side front plate 55 It is fixed to the end of the. In addition, although a part of front part of machine room S2 of the unit casing 51 is comprised here by the fan room side front board 55, you may be comprised by the machine room side front board 56 here. Further, the chamber side front plate 55 and the blower chamber side front plate 55 and the machine room side front plate 56 may be an integral member.

  The top plate 57 is a metal plate-like member that constitutes the top surface portion of the unit casing 51. The top plate 57 is fixed to the blower chamber side plate 53, the machine room side plate 54, and the blower chamber side front plate 55.

  The partition plate 58 is a metal plate-like member that is disposed on the bottom plate 52 and extends in the vertical direction. The partition plate 58 divides the internal space of the unit casing 51 into left and right to form a blower chamber S1 near the left side and a machine chamber S2 near the right side. The partition plate 58 has a curved shape such that a central portion in the front-rear direction protrudes toward the blower chamber S1. The lower portion of the partition plate 58 is fixed to the bottom plate 52, the front end portion thereof is fixed to the blower chamber side front plate 55, and the rear end portion thereof is the end of the outdoor heat exchanger 24 on the machine room S 2 side. It is fixed to the part.

  The outdoor fan 70 is a propeller fan in which a hub 71 and a plurality of (here, three) blades 72 formed so as to protrude from the outer periphery of the hub 71 are integrally molded with resin. The outdoor fan 70 is provided so as to face the front surface of the unit casing 51 in the blower chamber S1. More specifically, the outdoor fan 70 is provided at a position on the front surface side of the outdoor heat exchanger 24 so as to face the air outlet 55 a formed in the blower room side front plate 55. Here, a recessed portion 72a that is recessed toward the front edge side of the blade 72 is formed on the rear edge of the blade 72 in order to improve the blowing performance and suppress noise. The outdoor fan 70 is rotationally driven by a fan motor 79 disposed between the outdoor fan 70 and the outdoor heat exchanger 24 in the front-rear direction. The fan motor 79 is supported by a fan motor base 61 extending vertically between the top plate 57 and the bottom plate 52. The detailed configuration of the outdoor fan 70 will be described later.

  The bell mouth 80 is a member having a bell-shaped opening 81 having an opening at the center, and is provided on the outer peripheral side of the outdoor fan 70. That is, the bell mouth 80 is provided so as to face the front surface of the unit casing 51 in the blower chamber S <b> 1 like the outdoor fan 70, and the opening 81 surrounds the outer periphery of the outdoor fan 70. The bell mouth 80 is fixed to the front surface of the unit casing 51. A portion of the bell mouth 80 near the blower room side plate 53 is disposed close to the front end of the outdoor heat exchanger 24. Further, the portion of the bell mouth 80 near the machine room S <b> 1 is disposed close to the partition plate 58.

  The outdoor heat exchanger 24 is a substantially L-shaped heat exchanger panel, and is disposed on the bottom plate 52 along the left side surface and the back surface of the unit casing 51 in the blower chamber S1.

  The compressor 21 is a vertical cylindrical hermetic compressor and is disposed in the machine room S2.

  In addition, although illustration is abbreviate | omitted here, refrigerant circuit components, such as apparatuses other than the compressor 21, and a refrigerant pipe, are also arrange | positioned in machine room S2.

(2) Detailed structure of outdoor fan Next, the detailed structure of the outdoor fan 70 as an axial fan concerning this embodiment is demonstrated using FIGS. Here, FIG. 3 is a perspective view of the outdoor fan 70. FIG. 4 is a plan view of the positive pressure surface side of the outdoor fan 70. FIG. 5 is a plan view of the negative pressure surface side of the outdoor fan 70. FIG. 6 is a side view of the outdoor fan 70. FIG. 7 is an enlarged view of the base portion 73 of the blade 72 and the vicinity thereof. 8 is a cross-sectional view taken along the line II of FIG. FIG. 9 is an enlarged view of the leading edge rib 76 of FIG. 6 and the vicinity thereof. In the following description, the axis (rotation center) of the outdoor fan 70 is defined as the axis O, and the axis is defined as the rotation axis OO.

  As described above, the outdoor fan 70 is a propeller fan in which the hub 71 and a plurality of (here, three) blades 72 formed so as to protrude from the outer periphery of the hub 71 are integrally molded with resin. . The number of blades 72 is not limited to three, and may be four or more.

  The blade | wing 72 has the blade | wing shape which moved forward and inclined forward (refer FIG.4 and FIG.5). And the thickness of the blade | wing 72 is large in the base part 73 with the hub 71, and is small as it goes to an outer peripheral side (refer FIG. 9). The recessed part 72a formed in the rear edge of the blade | wing 72 is arrange | positioned rather than the base part 73 at the outer peripheral side (refer FIG.3, FIG5 and FIG.7). Here, the surface on the side into which air flows when the outdoor fan 70 is rotated (the upstream side in the air flow direction) is defined as the negative pressure surface 72b, and the surface on the opposite side (the downstream side in the air flow direction) is the positive surface. The pressure surface 72c is used.

  A first blade meat stealing portion 74 is formed at the base portion 73 of the blade 72 so that the radial ribs 75 extending radially toward the outer peripheral side are left. Further, a front edge rib 76 that is continuous with the front edge of the blade 72 is formed in a portion of the root portion 73 on the front edge side of the blade 72 relative to the radial rib 75. A second blade meat stealing portion 77 larger than the first blade meat stealing portion 74 is formed between the circumferential direction of the leading edge rib 76 and the radial rib 75.

  Specifically, the blade stealing portions 74 and 77 are formed on the suction surface 72 b of the blade 72. The blade stealing portions 74 and 77 are not formed on the negative pressure surface 72b, but may be formed only on the positive pressure surface 72c, or may be formed on both the negative pressure surface 72b and the positive pressure surface 72c. Good.

  The radial rib 75 has a thickness equivalent to that of the root portion 73, and its axial end is smoothly continuous with the blade surface of the blade 72 (see FIGS. 8 and 9). A plurality of radial ribs 75 (here, four) are arranged in the circumferential direction. That is, a plurality (four in this case) of the first blade meat stealing portions 74 are arranged so as to be located on both sides in the circumferential direction of the radial rib 75 from the rear edge side to the front edge side of the blade 72. And the 2nd blade meat stealing part 77 is arrange | positioned at the circumferential direction front edge side of the radial rib 75 arrange | positioned at the most front edge side among the some radial ribs 75. As shown in FIG. For this reason, two radial ribs 75 that are adjacent to each other with the first blade stealing portion 74 in the circumferential direction are smoothly continuous at their axial ends. The number of the radial ribs 75 is not limited to four, and may be three or less or five or more.

  Further, the radial ribs 75 extend on a straight line L extending radially from the axis O of the hub 71 toward the outer peripheral side when the hub 71 and the blades 72 are viewed from the axial direction (see FIG. 7). Further, the radial ribs 75 are arranged at equal intervals in the circumferential direction. In other words, all the first blade meat stealing portions 74 have the same circumferential dimension at any radial position, whereby the radial ribs 75 are arranged at equal intervals in the circumferential direction.

  In contrast, the circumferential interval between the second feather meat stealing portion 77 and the first feather meat stealing portion 74 is larger than the circumferential interval between the first feather meat stealing portion 74 ( (See FIGS. 5 and 7). That is, the second blade meat stealing portion 77 has a circumferential dimension larger than that of the first blade meat stealing portion 74 at the same radial position.

  The leading edge rib 76 is formed so as to protrude from the blade surface of the blade 72 in the axial direction at the leading edge of the base portion 73 in order to improve the strength at the leading edge of the blade 72. Here, the leading edge rib 76 has a substantially triangular prism shape, and is formed on both the negative pressure surface 72 b and the positive pressure surface 72 c of the blade 72. The circumferential width of the leading edge rib 76 is larger than the circumferential width of the radial rib 75 at the same radial position (see FIGS. 5 and 7). A substantially triangular recess 76a is formed in the portion of the front edge rib 76 near the hub 71 when the hub 71 and the blades 72 are viewed from the axial direction. The leading edge rib 76 is not formed on both the negative pressure surface 72b and the positive pressure surface 72c, but may be formed only on the negative pressure surface 72b or the positive pressure surface 72c.

  Further, a rear edge rib 78 projecting in the axial direction from the blade surface of the blade 72 is formed at a portion of the root portion 73 on the rear edge side of the first blade meat stealing portion 74. The trailing edge rib 78 is formed on the negative pressure surface 72 b and the positive pressure surface 72 c of the blade 72. That is, the first blade meat stealing portion 74 and the radial rib 75 are formed in the portion near the front edge of the base portion 73 and are not formed in the portion near the rear edge. The first blade meat stealing portion 74 is located closer to the front edge of the blade 72 than the recessed portion 72a when the hub 71 and the blade 72 are viewed from the axial direction (arranged closest to the rear edge in FIG. 7). (See the straight line M extending from the first blade stealing portion 74 to the outer peripheral side).

(3) Molding of outdoor fan Next, the molding process of the outdoor fan 70 as an axial fan according to the present embodiment will be described with reference to FIGS. 10 and 11. Here, FIG. 10 is a side cross-sectional view of the mold 90 for explaining the molding process of the outdoor fan 70. FIG. 11 is a cross-sectional view showing the base portion 73 of the blade 72 of the mold 90 and the portion forming the vicinity thereof for explaining the molding process of the outdoor fan 70.

  First, an injection molding apparatus (not shown) having a mold 90 is prepared. The mold 90 includes a first mold 91 and a second mold 92 that is movable with respect to the first mold 91. And the cavity 93 which comprises the shape of the outdoor fan 70 is formed by combining the 1st metal mold | die 91 and the 2nd metal mold | die 92 (refer FIG. 10).

  Next, a resin is injected from the gate 94 provided in the first mold 91. The pouring gate 94 is provided so as to inject the resin into the cavity 93 from a position close to the axis O of the cavity 93 (here, a portion forming the hub 71 of the outdoor fan 70). Then, the resin flows from the inner peripheral portion of the cavity 93 toward the outer peripheral side, and the resin spreads into the cavity 93. At this time, the resin flows into the outer peripheral side through the portions of the cavity 93 where the blade stealing portions 74 and 77, the radial ribs 75 and the leading edge ribs 76 are formed.

  Next, the mold 90 is cooled with cooling water or the like to solidify the resin.

  Next, the mold 90 is opened by releasing the combination of the first mold 91 and the second mold 92. Then, the molded outdoor fan 70 is taken out from the mold 90.

(4) Features of outdoor fan The outdoor fan 70 as an axial fan of the present embodiment has the following features.

  First, in the outdoor fan 70 of the present embodiment, as described above, the first blade meat stealing is performed such that the radial ribs 75 extending radially toward the outer peripheral side are left at the base portion 73 of the blade 72 with the hub 71. A portion 74 is formed. Here, when the hub 71 and the blade | wing 72 are seen from an axial direction, the radial rib 75 shall extend on the straight line L extended radially from the axial center O of the hub 71 toward an outer peripheral side (FIG.5 and FIG.5). 7).

  This radial rib 75 is a study of the rib shape in consideration of the inflow of the resin at the time of molding the outer peripheral side of the meat stealing portion when the inventor forms the meat stealing portion at the base portion 73 of the blade 72. It was discovered by doing.

  Such radial ribs 75 promote the flow of the resin injected into the mold 90 toward the outer peripheral side at the time of molding, so that the resin on the outer peripheral side of the first blade meat stealing portion 74 at the time of molding is reduced. The flow can be improved. Also, the radial rib 74 is more likely to allow the resin injected into the mold during molding to flow toward the outer peripheral side as compared with the case where the rib that does not extend radially is left. In particular, here, since the radial ribs 75 extend on the straight line L, the resin injected into the mold 90 during molding flows straight toward the outer peripheral side, and the resin moves toward the outer peripheral side. Furthermore, it is easier to flow (see FIG. 11).

  Thereby, in the outdoor fan 70 of this embodiment, a meat stealing part can be formed in the base part 73 of the blade | wing 72, suppressing the molding defect in the outer peripheral part of the blade | wing 72. FIG.

  Further, in the outdoor fan 70 of the present embodiment, as described above, a plurality of radial ribs 75 (here, four) are arranged in the circumferential direction (see FIGS. 5 and 7).

  For this reason, at the time of shaping | molding, the part which resin flows into the part of the outer peripheral side rather than the 1st blade meat stealing part 74 can be increased in the circumferential direction (refer FIG. 11).

  Thereby, in the outdoor fan 70 of this embodiment, it can further accelerate | stimulate that the resin inject | poured into the metal mold | die 90 flows toward an outer peripheral side at the time of shaping | molding. Further, at the time of molding, the resin can easily flow evenly at any position in the circumferential direction of the portion on the outer peripheral side of the first blade meat stealing portion 74.

  Further, in the outdoor fan 70 of the present embodiment, as described above, the front edge rib 76 that is continuous with the front edge of the blade 72 is formed in the base portion 73 on the front edge side of the blade 72 relative to the radial rib 75. ing. And the 2nd blade meat stealing part 77 larger than the 1st blade meat stealing part 74 is formed between the circumferential directions of the front edge rib 76 and the radial rib 75 (refer FIG.5 and FIG.7).

  Here, as described above, the leading edge rib 76 is formed in order to improve the strength at the leading edge of the blade 72, and the circumferential width thereof is larger than that of the radial rib 75 (FIG. 5). And FIG. 7). For this reason, there is a possibility that the leading edge rib 76 and its vicinity are difficult to be cooled during molding.

  In contrast, in the outdoor fan 70 of the present embodiment, as described above, the second blade meat stealing portion 75 that is larger than the first blade meat stealing portion 74 between the front edge ribs 76 and the radial ribs 75 in the circumferential direction. Is forming. For this reason, it can suppress that it becomes difficult to cool the front edge rib 76 and its vicinity.

  Thereby, in the outdoor fan 70 of this embodiment, although not only the radial rib 75 but the front edge rib 76 is formed, it can suppress that the sink mark at the time of shaping | molding generate | occur | produces.

  Further, in the outdoor fan 70 of the present embodiment, the radial ribs 70 are arranged at equal intervals in the circumferential direction (see FIGS. 5 and 7).

  For this reason, at the time of shaping | molding, resin becomes easy to flow equally with respect to several (here four) radial ribs 75 (refer FIG. 11).

  Thereby, in the outdoor fan 70 of this embodiment, at the time of shaping | molding, it can make it easier for resin to flow into the part of the outer peripheral side rather than the 1st blade meat stealing part 74 further in the circumferential direction.

  Furthermore, in the outdoor fan 70 of the present embodiment, a recessed portion 72 a that is recessed toward the front edge side of the blade 72 is formed at the rear edge of the blade 72. And the 1st blade meat stealing part 74 is located in the front edge side of the blade | wing 72 rather than the recessed part 72a, when the hub 71 and the blade | wing 72 are seen from an axial direction (refer FIG. 7).

  Here, as described above, the recess 72a is formed in order to improve the blowing performance and suppress noise, and the resin hardly flows into the recess 72a and the vicinity thereof during molding. For this reason, there exists a possibility that the molding defect of the recessed part 72a and its vicinity may generate | occur | produce at the time of shaping | molding.

  On the other hand, in the outdoor fan 70 of the present embodiment, as described above, the first blade meat stealing portion 74 is positioned on the front edge side of the blade 72 relative to the recessed portion 72a. For this reason, at the time of molding, the resin can flow into the recessed portion 72a and the vicinity thereof without passing through the first blade meat stealing portion 74.

  Thereby, in the outdoor fan 70 of this embodiment, although both the 1st blade meat stealing part 74 and the recessed part 72a are formed, the resin flows into the recessed part 72a and its vicinity at the time of shaping | molding. It is possible to secure molding defects in the recess 72a and the vicinity thereof.

  The present invention can be widely applied to an axial fan in which a hub and a plurality of blades formed so as to protrude from the outer peripheral edge of the hub are integrally formed with a resin.

70 Axial fan 71 Hub 72 Blade 72a Recessed portion 73 Base portion 74 First blade meat stealing portion 75 Radial rib 76 Leading edge rib 77 Second blade meat stealing portion

JP 2011-74817 A

Claims (5)

In the axial fan in which the hub (71) and a plurality of blades (72) formed so as to protrude from the outer peripheral edge of the hub are integrally molded with resin,
A first blade meat stealing portion (74) is formed at the base portion (73) of the blade with the hub so that radial ribs (75) extending radially toward the outer peripheral side are left behind ,
A leading edge rib (76) continuous to the leading edge of the blade is formed in a portion of the root portion (73) on the leading edge side of the blade (72) with respect to the radial rib (75).
Between the circumferential direction of the front edge rib and the radial rib, a second blade meat stealing portion (77) larger than the first blade meat stealing portion (74) is formed,
An axial fan (70). A plurality of the radial ribs (75) are arranged in the circumferential direction,
The axial fan (70) according to claim 1. The radial rib (75) extends on a straight line extending radially from the axial center of the hub toward the outer peripheral side when the hub (71) and the blade (72) are viewed from the axial direction.
The axial fan (70) according to claim 1 or 2. The radial ribs (75) are arranged at equal intervals in the circumferential direction,
The axial fan (70) according to any one of claims 2 or 3 . On the rear edge of the blade (72), a recess (72a) is formed that is recessed toward the front edge of the blade.
The first blade meat stealing portion (74) is located on the front edge side of the blade from the recessed portion when the hub (71) and the blade (72) are viewed from the axial direction.
The axial fan (70) according to any one of claims 1 to 4 .

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