Patent Publication Number: US-11041506-B2

Title: Blower fan and air conditioner having same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS AND CLAIM OF PRIORITY 
     This application is a 371 of International Application No. PCT/KR2016/012616 filed Nov. 4, 2016, which claims priority to Korean Patent Application No. 10-2015-0168770 filed Nov. 30, 2015, the disclosures of which are herein incorporated by reference in their entirety. 
     TECHNICAL FIELD 
     The present disclosure relates to a blower fan and an air conditioner having the same, and more particularly, to a blower fan capable of reducing blowing noise and power consumption due to an operation of a propeller fan and an air conditioner having the same. 
     BACKGROUND 
     Air conditioner is an apparatus which keeps indoor air fresh to be suitable for human activity using a refrigeration cycle. The air conditioner cools the room through a repetitive operation which sucks hot air in a room, heat-exchanges the hot air into a low-temperature refrigerant, and discharges the refrigerant to the room. The air conditioners may heat the room through the reverse operation to the repetitive operation. 
     The air conditioner may cool or heat the room through a cooling cycle in which the air circulates in a compressor, a condenser, an expansion valve, and an evaporator in the forward or reverse direction. The compressor provides the high-temperature and high-pressure gaseous refrigerant and the condenser provides the room-temperature and high-pressure liquid refrigerant. The expansion value reduces the pressure of the room-temperature and high-pressure liquid refrigerant and the evaporator evaporates the pressure-reduced refrigerant to a low-temperature gas state. 
     The air conditioners may be divided into a separate type air conditioner in which an outdoor unit and an indoor unit are separated from each other and an integrated type air conditioner in which the indoor unit and the outdoor unit are integrally installed. Typically, in the separated type air conditioner, the compressor and the condenser (outdoor heat exchanger) are provided in the outdoor unit and the evaporator (indoor heat exchanger) is provided in the indoor unit. The refrigerant circulates and flows in the outdoor unit and the indoor unit via a pipe which couples the indoor unit and the outdoor unit. 
     The outdoor unit in the separate type air conditioner includes the compressor, the condenser, a blower fan, a driving motor which rotates the blower fan, and the like. The driving motor rotates the blower fan, condenses the refrigerant to a liquid state through heat exchange with the gaseous refrigerant flowing inside the condenser of the outdoor unit, and discharges the condensed refrigerant to the outside. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Summary 
     The object of the present disclosure is to provide a blower fan capable of reducing blowing noise and power consumption and an air conditioner having the same. 
     According to an embodiment of the present invention, a blower fan may include a hub coupled to a driving member and configured to receive rotation force; and a plurality of wings radially arranged along a circumference of the hub. Each of the plurality of wings may include an uneven part formed at a trailing edge which is a rear edge portion of the wing with respect to a rotational direction thereof; and a tail wing part having a convex portion which is formed on an outer side of the uneven part and protrudes rather than the uneven part. 
     A position P 1  of the tail wing part may be located in a section 0.85*D≤P 1 ≤D on the basis of a maximum straight distance D of the wing from a center C of the hub. 
     A position P 2  of the uneven part may be located in the section 0.5*D≤P 2 ≤0.9*D. 
     The uneven part may be located from an inner end of the tail wing part toward the center C of the hub by an interval of 0.01*D or less. 
     The tail wing part may have an inclined portion which is coupled to an inner side of the convex portion and is arranged to be inclined upward toward the convex portion. 
     A protruding portion of the uneven part which protrudes from a surface of the trailing edge and a recessed portion of the uneven part which is recessed from the surface of the trailing edge may be alternately arranged and the recessed portion may be located closest to the convex portion. 
     The protruding portion may have a convex shape to have a preset curvature. 
     The protruding portion may have a polygonal shape. 
     The convex portion may have a convex shape to have a preset curvature and protrude backward rather than the uneven part with respect to the rotational direction. 
     An outer end of the tail wing part may be located in an end portion of the wing. 
     According to an embodiment of the present invention, an air conditioner may include a blower fan configured to cool a refrigerant. The blower fan may have a plurality of wings. Each of the plurality of wings may include an uneven part formed at a trailing edge which is a rear edge portion of the wing with respect to a rotational direction thereof; and a convex portion formed on an outer side of the uneven part and having a preset curvature to protrude backward rather than the uneven part with respect to the rotational direction. 
     The wing may further include a tail wing part formed in an end portion of a trailing edge of the wing and the convex portion may be provided in the tail wing part. 
     The blower fan may further include a hub coupled to a driving shaft and configured to receive rotation force. 
     The plurality of wings may be arranged along a circumference of the hub. A position P 1  of the tail wing part may be located in a section 0.85*D≤P 1 ≤D on the basis of a maximum straight distance D of the wing from a center C of the hub. 
     A position P 2  of the uneven part may be located in a section 0.5*D≤P 2 ≤0.9*D. 
     The uneven part may be located from an inner end of the tail wing part toward the center C of the hub by an interval of 0.01*D or less. 
     The tail wing part may have an inclined portion which is coupled to an inner side of the convex portion and is arranged to be inclined upward toward the convex portion. 
     A protruding portion of the uneven part which protrudes from a surface of the trailing edge and a recessed portion of the uneven part which is recessed from the surface of the trailing edge may be alternately arranged and the recessed portion may be located closest to the convex portion. 
     The protruding portion may have a convex shape to have a preset curvature. 
     The protruding portion may have a polygonal shape. 
     An outer end of the tail wing part may be located in an end portion of the wing. To obtain the above-described object, according to an embodiment of the present invention, an air conditioner may include a blower fan configured to cool a refrigerant. The blower fan may have a plurality of wings. 
     Each of the plurality of wings may include an uneven part formed at a trailing edge which is a rear edge portion of the wing with respect to a rotational direction thereof; and a convex portion formed on an outer side of the uneven part and having a preset curvature to protrude from the uneven part. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram illustrating an air conditioner according to an embodiment of the present invention. 
         FIG. 2  is a perspective view illustrating a figure of a blower fan according to an embodiment of the present invention. 
         FIG. 3  is a front view illustrating a figure of a blower fan according to an embodiment of the present invention. 
         FIG. 4  is an enlarged view illustrating an A portion of the blower fan illustrated in  FIG. 3 . 
         FIG. 5  is a diagram illustrating a comparison between a magnitude of noise to an air volume in a blower fan according to an embodiment of the present invention and a magnitude of noise to an air volume in a blower fan in the related art. 
         FIG. 6  is a diagram illustrating a comparison between a value of power consumption to an air volume in a blower fan according to an embodiment of the present invention and a value of power consumption to an air volume in a blower fan in the related art. 
         FIG. 7  is a diagram illustrating a modified example of a wing illustrated in  FIG. 4 . 
         FIG. 8  is a diagram illustrating another modified example of a wing illustrated in  FIG. 4 . 
         FIG. 9  is a front view illustrating a blower fan according to another embodiment of the present invention. 
         FIG. 10  is an enlarged view illustrating a B portion of the blower fan illustrated in  FIG. 9 . 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying  FIGS. 1 to 10 . The embodiments described herein will be exemplarily described based on embodiments most suitable to understand technical features of the present invention. It is understood that the technical features of the present invention are not limited by the embodiments described herein but are illustrated to implement the present invention like the embodiments described herein. 
     Various modifications, equivalents, and/or alternatives of the embodiments may be included therein without departing from the principles and spirit of the present disclosure. In the following description, unless otherwise described, the same reference numerals are used for the same elements when they are depicted in different drawings. 
       FIG. 1  is a schematic diagram illustrating an air conditioner according to an embodiment of the present invention. Referring to  FIG. 1 , an air conditioner  100  includes an indoor unit  10  and an outdoor unit  20 . The indoor unit  10  and the outdoor unit  20  may be coupled to a coupling pipe  30 . The coupling pipe  30  may include a refrigerant supply pipe  40  and a refrigerant discharge pipe  50 . The refrigerant may circulate in a refrigerant tube (not shown) provided in the indoor unit  10  and a refrigerant tube (not shown) provided in the outdoor unit  20  through the coupling pipe  30 . 
     The indoor unit  10  may maintain the indoor temperature to an appropriate temperature by discharging the air heat-exchanged with the refrigerant compressed and condensed in the outdoor unit  20  to the room. The indoor unit  10  may include an expansion value and an evaporator. The indoor air may be cooled through the refrigerant evaporated in the evaporator. 
     The outdoor unit  20  may include a compressor, a condenser, and a blower fan  200 . An air inlet through which external air flows in or flows out may be formed in one side of the outdoor unit  20 . The compressor compresses the refrigerant and the compressed refrigerant flows and is condensed in the condenser. At this time, the blower fan  200  may be driven and the heat generated in the condenser may be cooled through the external air flowing through the air inlet and then discharged to the outside of the outdoor unit  20  again through the blower fan  200 . 
     A propeller fan may be used as the blower fan  200  of the outdoor unit  20 . The blower fan  200  may be used in the outdoor unit  20  of the air conditioner  100  and the like and may allow the air to forcibly flow by a difference between pressures in the front and rear of the blower fan. 
     Hereinafter, a structure of a blower fan will be described in detail with reference to the accompanying drawings. 
       FIG. 2  is a perspective view illustrating a figure of a blower fan according to an embodiment of the present invention and  FIG. 3  is a front view illustrating a figure of a blower fan according to an embodiment of the present invention. Further,  FIG. 4  is an enlarged view illustrating an A portion of the blower fan illustrated in  FIG. 3 . Referring to  FIGS. 2 to 4 , the blower fan  200  according to an embodiment of the present invention includes a hub  110  and a plurality of wings  120 . 
     A shaft (not shown) of a driving member (not shown) may be coupled to the hub  110 . The hub  110  is firmly coupled to the shaft of the driving member through a screw fastening structure and the like and receives rotational force from the shaft. Accordingly, the blower fan  200  may be rotated through the driving force of the driving member. For example, the driving member may be a driving motor. 
     The wings  120  may be radically arranged in a circumference of the hub  110  at intervals. The plurality of wings  120  may be provided in the same shape. Each of the wings  120  may be provided to have a gentle slope so as to blow the air in the rear of the blower fan  200  to a forward direction along an axis direction. 
     The wing  120  may include a trailing edge  121  and a leading edge  122 . The leading edge  122  refers to a front edge portion with respect to a rotational direction (a clockwise direction on the basis of  FIG. 3 ) of the wing  120  and the trailing edge  121  refers to a rear edge portion with respect to the rotational direction of the wing  120 . The leading edges  122  and the trailing edges  121  of the wings may be arranged close to each other to face each other. 
     The air flowing into a wing  120  side through the leading edge  122  according to the rotation of the blower fan  200  flows along the front surface of the wing  120  and is discharged from the trailing edge  121 . The wing  120  may be provided to have a gentle slope toward the front of the blower fan  200  from the leading edge  122  toward the trailing edge  121 . Accordingly, in response to the rotation of the blower fan  200 , the air flowing into the leading edge  122  may flow along the front surface of the wing  120  inclined toward the front of the blower fan  200  and thus the air may be blown along the axis direction of the blower fan  200  from the rear of the blower fan  200  to the front thereof. 
     The trailing edge  121  may have an uneven part  130  and a tail wing part  140 . The uneven part  130  may have a protruding portion  131  and a recessed portion  132  so that the trailing edge  121  is curved. The protruding portion  131  and the recessed portion  132  are alternately arranged so that the uneven part  130  may have a curved shape. 
     For example, the protruding portion  131  may have a crest shape of a wave and the recessed portion  132  may have a trough shape of the wave. Accordingly, the uneven part  130  may have a wave shape having the crest and trough periodically. The protruding portion  131  and the recessed portion  132  may have a preset curvature. 
     The protruding portion  131  protrudes from a surface of the trailing edge  121  and the recessed portion  132  may be recessed from the surface of the trailing edge  121 . A position P 2  of the uneven part  130  may be located in a section 0.5*D≤P 2 ≤0.9*D on the basis of a distance (hereinafter, referred to as maximum straight distance D) from the center C of the hub  110  to an end portion of the wing  120 . 
     Here, the position P 2  of the uneven part  130  means that the uneven part  130  may be located in the section 0.5*D≤P 2 ≤0.9*D in the distance D from the center C of the hub  110  to the end portion of the wing  120  and the position P 2  of the uneven part  130  may correspond to a length of the uneven part  130 . A width of the uneven part  130  in the position P 2  may be flexibly changed within the section 0.5*D≤P 2 ≤0.9*D. 
     The tail wing part  140  may be located in the outer side of the uneven part  130  and have an inclined portion  141  and a convex portion  142 . The convex portion  142  is formed in the outer side of the uneven part  130 . The convex portion  142  is arranged in the outer side of the uneven part  130  and has a protruding shape from the trailing edge  121 . The convex portion  142  may have a preset curvature to protrude toward a rear side with respect to the rotational direction of the blower fan  200  and a front end of the convex portion  142  may be formed higher than a front end of the protruding portion  131 . 
     The inclined portion  141  is coupled to an inner side of the convex portion  142  and is coupled to be inclined upward toward the convex portion  142 . Although the inclined portion  141  is illustrated in a linear shape, the inclined portion  141  may have a curved form to be inclined upward toward the convex portion  142 . A position P 1  of the tail wing part  140  may be located in a section 0.85*D≤P 1 ≤D on the basis of the maximum straight distance D. 
     Here, the position P 1  of the tail wing part  140  means that the tail wing part  140  may be located in the section 0.85*D≤P 1 ≤D in the distance D from the center C of the hub  110  to the end portion of the wing  120 . Here, the outer end of the tail wing part  140  may be arranged in the end portion of the wing  120 . The width of the tail wing part  140  may have the largest width in response to the inner end of the tail wing part  140  being arranged in 0.85*D. For example, the width of the tail wing part  140  may be 0.15*D. In response to an inner portion of the tail wing part  140  being located in a section between 0.85*D and D, the width of the tail wing part  140  may be flexibly changed. 
     Referring to  FIG. 4 , the uneven part  130  may be formed from an inner side of the tail wing part  140  (or inclined portion  141 ) toward the center C of the hub  110  and a pitch of the uneven part  130  may be located to have an interval d of 0.01*D or less on the basis of the maximum straight distance D. The protruding portion  131  may protrude to a present height h from the surface of the trailing edge  121 . 
       FIG. 5  is a diagram illustrating a comparison between a magnitude of noise to an air volume in a blower fan according to an embodiment of the present invention and a magnitude of noise to an air volume in a blower fan (in which an uneven part and a tail wing part are not included) in the related art and  FIG. 6  is a diagram illustrating a comparison between a value of power consumption to an air volume in a blower fan according to an embodiment of the present invention and a value of power consumption to an air volume in a blower fan (in which an uneven part and a tail wing part are not included) in the related art. 
     It can be seen from  FIG. 5  that the blower fan  200  according to an embodiment of the present invention has an effect that the noise of about 1 dBA is reduced under the same air volume condition as compared with a blower fan in the related art. 
     It can be seen from  FIG. 6  that the blower fan  200  according to an embodiment of the present invention has an effect that the power consumption of about 3 W is reduced under the same air volume condition as compared with a blower fan in the related art. 
     Accordingly, the mixing action of the flow of a pressure surface and the flow of a negative pressure surface may be increased by forming the uneven part  130  and the tail wing part  140  in the wing  120  and thus the counter current strength of the counter current region and the counter current region in a slipstream may be reduced. As the counter current is reduced, the power consumption of the blower fan  200  may be reduced and the noise which may be generated in air suction and discharge process may be reduced and thus the satisfaction of the user may be improved. 
     The uneven part  130  and the tail wing part  140  may be provided to correspond to each wing  120 . A shape, a size, the number of uneven parts  130  and the like are not limited thereto and may be changed according to the structure and shape of the applied blower fan  200 . The shapes of the plurality of protruding portions  131  and recessed portions  132  constituting the uneven part  130  may be differently formed from each other. For example, the height of the protruding portion  131  close to the hub  110  may be formed larger than the protruding portion  131  close to the tail wing part  140 . 
     Hereinafter, modification examples of the wing  120  according to an embodiment described in  FIGS. 1 to 4  will be described. The modification examples to be described later will be described on the basis of a difference from the wing described in  FIGS. 1 to 4  and omitted description may be replaced with the above-described contents. 
       FIG. 7  is a diagram illustrating a modified example of the wing illustrated in  FIG. 4  and  FIG. 8  is a diagram illustrating another modified example of the wing illustrated in  FIG. 4 . As illustrated in  FIGS. 7 and 8 , uneven parts  130 A and  130 B may have a polygonal shape. 
     Referring to  FIG. 7 , a protruding portion  131 A may have a triangular shape. The protruding portion  131 A may have an equilateral triangular shape or an isosceles triangular shape of which a cross-sectional area is constantly reduced upward. 
     The protruding portions  131 A may be continuously arranged at intervals and the recessed portions  132 A may be formed between the protrusion portions  131 A. The protruding portions  131 A and the recessed portions  132 A may have a symmetrical shape with each other with respect to the surface of the trailing edge  121 . The protruding portion  131 A may be provided to protrude from the trailing edge  121  and the recessed portion  132 A may be provided to be recessed from the trailing edge  121 . 
     Referring to  FIG. 8 , the protruding portion  131 B may have a trapezoidal shape of which a cross-sectional area is constantly reduced upward. The protruding portions  131 B may be continuously arranged at intervals and the recessed portions  132 B may be formed between the protrusion portions  131 B. The protruding portions  131 B and the recessed portions  132 B may have a symmetrical shape with each other with respect to the surface of the trailing edge  121 . The protruding portion  131 B may be provided to protrude from the trailing edge  121  and the recessed portion  132 B may be provided to be recessed from the trailing edge  121 . 
       FIG. 9  is a front view illustrating a blower fan according to another embodiment of the present invention and  FIG. 10  is an enlarged diagram illustrating a B portion of the blower fan illustrated in  FIG. 9 . As described in  FIGS. 1 to 4 , a protruding portion  131 C protrudes the surface of the trailing edge  121  and a recessed portion  132 C is recessed from the surface of the trailing edge  121 . 
     A position P 2 ′ of an uneven part  130 C may be located in a section 0.5*D≤P 2 ′≤0.9*D on the basis of the maximum straight distance D. 
     A tail wing part  140 A may have an inclined portion  141 A and a convex portion  142 A. The convex portion  142 A is formed in the outer side of the uneven part  130 C. The convex portion  142 A is arranged on the outer side of the uneven part  130 C and has a protruding shape from the trailing edge  121 . The convex portion  142 A may have a preset curvature to protrude toward a rear side with respect to the rotational direction of the blower fan  200  and a front end of the convex portion  142 A may be formed higher than a front end of the protruding portion  131 C. 
     The inclined portion  141 A is coupled to an inner side of the convex portion  142 A and is arranged to be inclined upward toward the convex portion  142 A. A position P 1 ′ of the of the tail wing part  140 A may be located in a section 0.85*D≤P 1 ′≤D on the basis of the maximum straight distance D. 
     Referring to  FIGS. 9 and 10 , the uneven part  130 C may be formed on the tail wing part  140 A. 
     Here, the position P 1 ′ of the tail wing part  140 A means that the tail wing part  140 A may be located in the section 0.85*D≤P 1 ′≤D in the distance D from the center C of the hub  110  to an end portion of a wing  120 C. Here, the outer end of the tail wing part  140 A may be the end portion of the wing  120 C. 
     At this time, the width of the tail wing part  140 A may have the largest width in response to the inner end of the tail wing part  140 A being arranged in 0.85*D. In response to an inner portion of the tail wing part  140 A being located in a section between 0.85*D and D, the width of the tail wing part  140 A may be flexibly changed. 
     Here, the position P 2 ′ of the uneven part  130 C means that the uneven part  130 C may be located in the section 0.5*D≤P 2 ′≤0.9*D in the distance D from the center C of the hub  110  to the edge portion of the wing  120 C. The width of the uneven part  130 C may be flexibly changed in the section 0.5*D≤P 2 ′≤0.9*D. 
     For example, in response to the position P 1 ′ of the tail wing part  140 A being formed in 0.86*D≤P 1 ′≤D, the position P 2 ′ of the uneven part  130 C may be formed in 0.5*D≤P 2 ′≤0.89*D. In this case, the position P 2 ′ of the uneven part  130 C may be formed to partially overlap the position P 1 ′ of the tail wing part  140 A (0.86*D≤P 1 ′∩P 2 ′≤0.89*D). In response to a distance ratio of the inclined portion  141 A and the convex portion  142 A being 1:1, the uneven part  130 C may be formed on the inclined portion  141 A. 
     In the blower fans  200  described in the embodiments of the present invention, air flows in along the leading edge  122 . The flowing-in air flows along the wing  120  and the flow of the air may be changed through the uneven part  130  and the tail wing part  140  provided in the trailing edge  121  in response to the air being discharged to the training edge  121 . 
     At this time, since the blower fan  200  can mix the flow of the pressure surface and the flow of the negative pressure surface near the uneven part  130 , the blower fan  200  may effectively reduce the strength and region of the counter current which may be generated in the discharged air. The blower fan can simultaneously reduce the noise and power consumption through control of the generation of the counter current. 
     The various embodiments of the present invention have been separately described above, but the embodiments may not be inevitably separately implemented and the configuration and operation of each of the embodiments may be implemented through the combination of at least one of other embodiments. 
     The foregoing exemplary embodiments and advantages are merely exemplary and are not to be construed as limiting the present inventive concept. The description of the exemplary embodiments is intended to be illustrative, and not to limit the scope of the claims, and many alternatives, modifications, and variations will be apparent to those skilled in the art.