Patent Publication Number: US-11397011-B2

Title: Air-sending device and refrigeration cycle apparatus

Description:
TECHNICAL FIELD 
     The present disclosure relates to an air-sending device including a fan grille, and a refrigeration cycle apparatus including the air-sending device. 
     BACKGROUND ART 
     There has been proposed an air-sending device including a propeller fan and a bell mouth, as an air-sending device to be mounted on a refrigeration cycle apparatus or other apparatuses. The bell mouth is a component that surrounds the outer periphery of the propeller fan to form an air passage. Some air-sending devices including a propeller fan and a bell mouth further includes a fan grille disposed downstream of an air outlet of the bell mouth in the direction of airflow generated by the propeller fan. The fan grille is a component that covers the propeller fan and the air outlet of the bell mouth to prevent human fingers from coming into contact with the propeller fan, while allowing ventilation. 
     The noise and energy loss that occur when driving the air-sending device are caused by the ventilation resistance and disturbance of airflow in the air-sending device. Here, as described above, the fan grille is a component that prevents human fingers from coming into contact with the propeller fan. Accordingly, the fan grille includes a plurality of crosspieces arranged at intervals that prevent human fingers from being inserted therebetween. Therefore, the fan grille is likely to increase the ventilation resistance and disturbance of airflow. 
     To solve this problem, there has been proposed an air-sending device including a propeller fan, a bell mouth, and a fan grille, wherein the fan grille has a shape that reduces the ventilation resistance and disturbance of airflow. For example, a fan grille of an air-sending device disclosed in Patent Literature 1 includes a plurality of horizontal crosspieces. Each of the horizontal crosspieces has a shape in which a dimension in the direction from its upstream side end portion to its downstream side end portion is larger than a dimension in the direction perpendicular to that direction, in a cross-section perpendicular to the longitudinal direction of the horizontal crosspiece. That is, each of the horizontal crosspieces has an elongated shape in the direction from its upstream side end portion to its downstream side end portion, in the cross-section perpendicular to the longitudinal direction of the horizontal crosspiece. Further, each of the horizontal crosspieces is twisted such that one longitudinal end and the other longitudinal end thereof are inclined in opposite directions. The horizontal crosspieces are twisted at the same angle. The airflow blown out from the propeller fan is a swirling flow. Therefore, according to Patent Literature 1, by configuring each horizontal crosspiece as in Patent Literature 1, the direction from the upstream side end portion to the downstream side end portion can be aligned with the direction of airflow blown out from the propeller fan. That is, according to Patent Literature 1, by configuring each horizontal crosspiece as in Patent Literature 1, it is possible to reduce the ventilation resistance and disturbance of airflow, and to reduce noise and energy loss that occur when driving the air-sending device. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2007-163036 
     SUMMARY OF INVENTION 
     Technical Problem 
     The direction of airflow blown out from a propeller fan, that is, the degree of inclination of a swirling flow with respect to the rotation axis of a propeller fan is affected not only by the blade shape of the propeller fan but also by the shape of a bell mouth. For example, if an air outlet of a bell mouth is circular, that is, if an air outlet of a bell mouth is axially symmetric with respect to the rotation axis of a propeller fan, the degree of inclination of a swirling flow with respect to the rotation axis of the propeller fan is constant. In other words, if the distance between the edge of the air outlet of the bell mouth and the rotation axis of the propeller fan is constant, the degree of inclination of the swirling flow with respect to the rotation axis of the propeller fan is constant. The propeller fan disclosed in Patent Literature 1 is designed on the premise that the air outlet of the bell mouth is circular. Therefore, in the case where the air outlet of the bell mouth is circular, if each horizontal crosspiece is configured as in Patent Literature 1, the direction from the upstream side end portion to the downstream side end portion can be aligned with the direction of airflow blown out from the propeller fan. That is, in the case where the air outlet of the bell mouth is circular, if each horizontal crosspiece is configured as in Patent Literature 1, it is possible to reduce the ventilation resistance and disturbance of airflow, and to reduce noise and energy loss that occur when driving the air-sending device. 
     In recent years, there have been cases where, to reduce the size of a casing in which an air-sending device is mounted, a part of the edge of an air outlet of a bell mouth is displaced toward the rotation axis of a propeller fan. That is, an air outlet of a bell mouth is often axially asymmetric with respect to the rotation axis of a propeller fan. In this case, the distance between the edge of the air outlet of the bell mouth and the rotation axis of the propeller fan varies with the position. Accordingly, the degree of inclination of a swirling flow with respect to the rotation axis of the propeller fan varies with the position, at the air outlet of the bell mouth. Specifically, when viewed in the rotation direction of the propeller fan, in the range where the distance between the edge of the air outlet of the bell mouth and the rotation axis of the propeller fan decreases, the airflow blown out of the propeller fan is accelerated, so that the inclination of the swirling flow with respect to the rotation axis of the propeller fan is reduced. On the other hand, when viewed in the rotation direction of the propeller fan, in the range where the distance between the edge of the air outlet of the bell mouth and the rotation axis of the propeller fan increases, the airflow blown out of the propeller fan is decelerated, so that the inclination of the swirling flow with respect to the rotation axis of the propeller fan is increased. 
     In this manner, in the case where an air outlet of a bell mouth is axially asymmetric with respect to the rotation axis of a propeller fan, the inclination of a swirling flow with respect to the rotation axis of the propeller fan varies with the position, at the air outlet of the bell mouth. Accordingly, in the case of an air-sending device in which an air outlet of a bell mouth is axially asymmetric with respect to the rotation axis of a propeller fan, even if the configuration of the horizontal crosspieces of Patent Literature 1 is adopted to a fan grille; the direction from the upstream side end portion to the downstream side end portion is not aligned with the direction of airflow blown out from the propeller fan. As a result; it is not possible to reduce noise and energy loss that occur when driving the air-sending device. 
     The present disclosure has been made to solve the above problem. A first object of the present disclosure is to provide an air-sending device in which an air outlet of a bell mouth is axially asymmetric with respect to the rotation axis of a propeller fan, the air-sending device including a fan grille that makes it possible to reduce noise and energy loss that occur when driving the air-sending device as compared to the related art. A second object of the present disclosure is to provide a refrigeration cycle apparatus including the air-sending device. 
     Solution to Problem 
     An air-sending device according to an embodiment of the present disclosure includes: a propeller fan configured to rotate about a rotation axis; a bell mouth having an air outlet and surrounding an outer periphery of the propeller fan; and a fan grille disposed downstream of the air outlet in a direction of airflow generated by the propeller fan; the fan grille including a plurality of first crosspieces; each of the plurality of first crosspieces having an upstream side end portion and a downstream side end portion, the upstream side end portion being positioned on an upstream side of the airflow; the downstream side end portion being positioned on a downstream side of the airflow, wherein the air-sending device is configured such that where in a cross-section of any of the plurality of first crosspieces, the cross-section being perpendicular to a longitudinal direction of the any of the plurality of first crosspieces, a virtual line segment connecting the upstream side end portion and the downstream side end portion is a first virtual line segment, an acute angle of angles formed by the first virtual line segment and a virtual line segment extending in parallel to the rotation axis, the acute angle being formed on a side of the downstream side end portion, is an inclination angle, and on a virtual plane that is orthogonal to the rotation axis and on which the rotation axis, the air outlet and the plurality of first crosspieces are projected, a position of the rotation axis on the virtual plane is a center point, a virtual line segment connecting between the center point and any one point of an edge of the air outlet is a second virtual line segment, a length of the second virtual line segment is a radial distance, a first point is a point on the edge of the air outlet, from which the radial distance decreases when the second virtual line segment rotates about the center point in a rotation direction of the propeller fan, a second point is a point on the edge of the air outlet, from which the radial distance increases when the second virtual line segment rotates about the center point in the rotation direction past the first point, a third point is a point on the edge of the air outlet, from which the radial distance no longer increases when the second virtual line segment rotates about the center point in the rotation direction past the second point, a fourth point is a point on the edge of the air outlet, a point located before the second point and after the first point in the rotation direction, being a midpoint between the first point and the second point, a fifth point is a point on the edge of the air outlet, a point located before the third point and after the second point in the rotation direction, being a midpoint between the second point and the third point, a sixth point is a point on the edge of the air outlet, located before the fourth point and after the first point in the rotation direction, and the radial distance between the center point and the sixth point is a first radial distance, a seventh point is a point on the edge of the air outlet, located before the third point and after the fifth point in the rotation direction, and the radial distance between the center point and the seventh point is the first radial distance, a virtual line segment connecting between the center point and the sixth point is a third virtual line segment, a virtual line segment connecting between the center point and the seventh point is a fourth virtual line segment, an eighth point is a point of intersection of a virtual circle having a center being the center point and the third virtual line segment of the plurality of first crosspieces, a ninth point is a point of intersection of the virtual circle and the fourth virtual line segment of the plurality of first crosspieces, the cross-section at the eighth point and the ninth point has a shape in which a dimension in a first direction from the upstream side end portion to the downstream side end portion is larger than a dimension in a second direction perpendicular to the first direction of the cross-section of the first crosspiece, and the inclination angle at the eighth point is smaller than the inclination angle at the ninth point. 
     A refrigeration cycle apparatus according to another embodiment of the present disclosure includes the air-sending device according to the above embodiment of the present disclosure, and a heat exchanger configured to exchange heat between refrigerant flowing inside and air supplied by the air-sending device. 
     Advantageous Effects of Invention 
     An air-sending device according to an embodiment of the present disclosure is configured such that an air outlet of a bell mouth is axially asymmetric round the rotation axis of a propeller fan, and such that even when the inclination of a swirling flow varies, the direction from an upstream side end portion to a downstream side end portion can be aligned with the direction of airflow blown out from the propeller fan, as compared to the related art. Accordingly, the air-sending device according to the above embodiment of the present disclosure is an air-sending device in which the air outlet of the bell mouth is axially asymmetric with respect to the rotation axis of the propeller fan, and it is possible to reduce noise and energy loss that occur when driving the air-sending device as compare to the related art. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  illustrates a propeller fan of an air-sending device according to Embodiment 1 of the present disclosure. 
         FIG. 2  is a perspective view of the air-sending device, with a fan grille removed, according to Embodiment 1 of the present disclosure. 
         FIG. 3  is a front view of the fan grille according to Embodiment 1 of the present disclosure. 
         FIG. 4  is a perspective view of the air-sending device, with the fan grille attached, according to Embodiment 1 of the present disclosure. 
         FIG. 5  is a cross-sectional view of a first crosspiece of the fan grille according to Embodiment 1 of the present disclosure, illustrating a cross-section of any first crosspiece perpendicular to a longitudinal direction of the first crosspiece. 
         FIG. 6  illustrates the air-sending device according to Embodiment 1 of the present disclosure, wherein a rotation axis and an air outlet of a bell mouth are projected on a virtual plane orthogonal to the rotation axis. 
         FIG. 7  is a view for explaining the distance between the rotation axis and the air outlet of the bell mouth, in the air-sending device according to Embodiment 1 of the present disclosure. 
         FIG. 8  is a view for explaining the state of a swirling flow of the air-sending device according to Embodiment 1 of the present disclosure. 
         FIG. 9  illustrates the air-sending device according to Embodiment 1 of the present disclosure, wherein the rotation axis, the air outlet of the bell mouth, and a plurality of first crosspieces are projected on a virtual plane orthogonal to the rotation axis. 
         FIG. 10  illustrates the air-sending device according to Embodiment 1 of the present disclosure, wherein the rotation axis, the air outlet of the bell mouth, and the plurality of first crosspieces are projected on a virtual plane orthogonal to the rotation axis. 
         FIG. 11  is a cross-sectional view of the first crosspieces at an eighth point and a ninth point of  FIG. 9 , illustrating cross-sections of the first crosspieces perpendicular to the longitudinal direction of the first crosspieces at the eighth point and the ninth point. 
         FIG. 12  illustrates the air-sending device according to Embodiment 1 of the present disclosure, wherein the rotation axis, the air outlet of the bell mouth, and the plurality of first crosspieces are projected on a virtual plane orthogonal to the rotation axis. 
         FIG. 13  illustrates an air-sending device according to Embodiment 2 of the present disclosure, wherein a rotation axis and an air outlet of a bell mouth are projected on a virtual plane orthogonal to the rotation axis. 
         FIG. 14  is a view for explaining the distance between the rotation axis and the air outlet of the bell mouth, in the air-sending device according to Embodiment 2 of the present disclosure. 
         FIG. 15  illustrates the air-sending device according to Embodiment 2 of the present disclosure, wherein the rotation axis, the air outlet of the bell mouth, and a plurality of first crosspieces are projected on a virtual plane orthogonal to the rotation axis. 
         FIG. 16  illustrates an example of changes in the inclination angle, in an air-sending device according to Embodiment 3 of the present disclosure. 
         FIG. 17  illustrates another example of changes in the inclination angle, in the air-sending device according to Embodiment 3 of the present disclosure. 
         FIG. 18  illustrates an air-sending device according to Embodiment 4 of the present disclosure, wherein a rotation axis, an air outlet of a bell mouth, and a plurality of first crosspieces are projected on a virtual plane orthogonal to the rotation axis. 
         FIG. 19  is a cross-sectional view of the first crosspieces at a fifteenth point and a sixteenth point of  FIG. 18 , illustrating cross-sections of the first crosspieces perpendicular to the longitudinal direction of the first crosspieces at the fifteenth point and the sixteenth point. 
         FIG. 20  illustrates an air-sending device according to Embodiment 5 of the present disclosure, wherein a rotation axis, an air outlet of a bell mouth, and a plurality of first crosspieces are projected on a virtual plane orthogonal to the rotation axis. 
         FIG. 21  is a cross-sectional view of the first crosspieces at a seventeenth point and an eighteenth point of  FIG. 20 , illustrating cross-sections of the first crosspieces perpendicular to the longitudinal direction of the first crosspieces at the seventeenth point and the eighteenth point. 
         FIG. 22  is an enlarged perspective view illustrating a part of a fan grille of an air-sending device according to Embodiment 6 of the present disclosure. 
         FIG. 23  illustrates the air-sending device according to Embodiment 6 of the present disclosure, wherein a rotation axis, an air outlet of a bell mouth, and the fan grille are projected on a virtual plane orthogonal to the rotation axis. 
         FIG. 24  is a perspective view of an outdoor unit of an air-conditioning apparatus according to Embodiment 7 of the present disclosure, as viewed from an air outlet. 
         FIG. 25  illustrates the internal configuration of the outdoor unit of the air-conditioning apparatus according to Embodiment 7 of the present disclosure as viewed from the above. 
         FIG. 26  is a perspective view illustrating the outdoor unit of the air-conditioning apparatus, with a fan grille removed, according to Embodiment 7 of the present disclosure, as viewed from the air outlet. 
         FIG. 27  is a perspective view illustrating the internal configuration of the outdoor unit of the air-conditioning apparatus according to Embodiment 7 of the present disclosure. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Embodiment 1 
       FIG. 1  illustrates a propeller fan of an air-sending device according to Embodiment 1 of the present disclosure. Note that  FIG. 1  illustrates a propeller fan  1  as viewed from the pressure surface side of blades  3  in the direction of a rotation axis  1   a  of the propeller fan  1 . The pressure surface of each blade  3  is the surface of one of the sides of the blade  3  that pushes out air. 
     The propeller fan  1  rotates about the rotation axis  1   a . Specifically, as indicated by the thin arc-shaped arrow in  FIG. 1 , the propeller fan  1  rotates about the rotation axis  1   a  in a rotation direction  4 . The propeller fan  1  includes a boss  2  that rotates about the rotation axis  1   a . The propeller fan  1  also includes the plurality of blades  3  on the outer periphery of the boss  2 , That is, the plurality of blades  3  rotate about the rotation axis  1   a , together with the boss  2 . 
     Each blade  3  includes, as edges, a leading edge  5 , a trailing edge  6 , and an outer peripheral edge  7 . The leading edge  5  is an edge on the front side in the rotation direction of the blade  3 . The trailing edge  6  is an edge on the rear side in the rotation direction of the blade  3 . The outer peripheral edge  7  is a portion defining the outer peripheral edge in the radial direction of the blade  3 . When the propeller fan  1  is rotated by a driving source (not illustrated) such as a motor in the rotation direction  4 , air flows on the surface of each blade  3  as indicated by airflow  8 . 
       FIG. 2  is a perspective view of the air-sending device, with a fan grille removed, according to Embodiment 1 of the present disclosure. Note that  FIG. 2  illustrates an air-sending device  40 , with a fan grille  20  removed, as viewed from an air outlet  11  side of a bell mouth  10 . 
     The air-sending device  40  according to Embodiment 1 includes the bell mouth  10 . The bell mouth  10  has the air outlet  11 , and surrounds the outer periphery of the propeller fan  1 . That is, the bell mouth  10  is a component that forms an air passage. 
     In general, the edge of an air outlet of a bell mouth is circular about the rotation axis of a propeller fan. That is, in general, the edge of an air outlet of a bell mouth is axially symmetric with respect to the rotation axis of a propeller fan. Meanwhile, an edge  12  of the air outlet  11  of the bell mouth  10  according to Embodiment 1 is axially asymmetric with respect to the rotation axis  1   a  of the propeller fan  1 . Specifically, the edge  12  of the air outlet  11  of the bell mouth  10  includes constant portions  13  and varying portions  14 . Each constant portion  13  is a portion of the edge  12  whose distance from the rotation axis  1   a  is constant. The constant portion  13  has the shape of a circular arc about the rotation axis  1   a  when the constant portion  13  is viewed in the direction of the rotation axis  1   a . Each varying portion  14  is a portion of the edge  12  whose distance from the rotation axis  1   a  varies. In Embodiment 1, the varying portion  14  has a linear shape when the varying portion  14  is viewed in the direction of the rotation axis  1   a.    
       FIG. 3  is a front view of the fan grille according to Embodiment 1 of the present disclosure.  FIG. 4  is a perspective view of the air-sending device, with the fan grille attached, according to Embodiment 1 of the present disclosure.  FIG. 5  is a cross-sectional view of a first crosspiece of the fan grille according to Embodiment 1 of the present disclosure, illustrating a cross-section of any first crosspiece perpendicular to a longitudinal direction of the first crosspiece. Note that  FIG. 4  illustrates the air-sending device  40 , with the fan grille  20  attached, as viewed from the air outlet  11  side of the bell mouth  10 .  FIG. 5  is, for example, a cross-sectional view of a first crosspiece  21  in the Z-Z cross-section of  FIG. 3 . The white arrow illustrated in  FIG. 5  indicates the direction of airflow  90  blown out from the propeller fan  1 , in the cross-section illustrated in  FIG. 5 . 
     The air-sending device  40  according to Embodiment 1 includes the fan grille  20  that covers the propeller fan  1  and the air outlet  11  of the bell mouth  10  to prevent human fingers from coming into contact with the propeller fan  1 , while allowing ventilation. The fan grille  20  is disposed downstream of the air outlet  11  of the bell mouth  10  in the direction of airflow generated by the propeller fan  1 . The fan grille  20  includes the plurality of first crosspieces  21 . The plurality of first crosspieces  21  are arranged at such intervals that prevent human fingers from being inserted between the adjacent first crosspieces  21 . That is, the fan grille  20  covers the propeller fan  1  and the air outlet  11  of the bell mouth  10 , with the plurality of first crosspieces  21 , while allowing ventilation. In  FIG. 3 , the first crosspieces  21  each extending in the vertical direction in the drawing are arranged at predetermined intervals in the lateral direction in the drawing. 
     The fan grille  20  includes a plurality of second crosspieces  22  each intersecting the first crosspieces  21 . In  FIG. 3 , the second crosspieces  22  each extending in the lateral direction in the drawing are arranged at predetermined intervals in the vertical direction in the drawing. That is, the plurality of first crosspieces  21  and the plurality of second crosspieces  22  are arranged in a mesh form. Each of the plurality of second crosspieces  22  supports the first crosspieces  21  to secure the strength of the first crosspieces  21 . In Embodiment 1, to reduce the ventilation resistance of the fan grille  20 , the number of the second crosspieces  22  is less than the number of first crosspieces  21 . 
     As illustrated in  FIG. 5 , each of the first crosspieces  21  has an elongated shape, such as an ellipse, in a cross-section perpendicular to the longitudinal direction of the first crosspiece  21 . Specifically, each of the first crosspieces  21  has an upstream side end portion  23  positioned on an upstream side and a downstream side end portion  24  positioned on a downstream side, in the direction of airflow generated by the propeller fan  1 . Further, each of the first crosspieces  21  has a shape in which a dimension in a first direction from the upstream side end portion  23  to the downstream side end portion  24  is larger than a dimension in a second direction perpendicular to the first direction, in the cross-section perpendicular to the longitudinal direction of the first crosspiece  21 . 
     Further, in the cross-section perpendicular to the longitudinal direction of the first crosspiece  21 , at least a part of the first crosspiece  21  is configured such that the longitudinal direction as the first direction is inclined with respect to the rotation axis  1   a  of the propeller fan  1 . Specifically, as illustrated in  FIG. 5 , in the cross-section perpendicular to the longitudinal direction of the first crosspiece  21 , a first virtual line segment  121  is a virtual line segment connecting between the upstream side end portion  23  and the downstream side end portion  24 . In  FIG. 5 , a virtual line segment  1   b  parallel to the rotation axis  1   a  of the propeller fan  1  is illustrated. As illustrated in  FIG. 5 , in the cross-section perpendicular to the longitudinal direction of the first crosspiece  21 , an inclination angle  140  is an acute angle that is one of angles formed by the first virtual line segment  121  and the virtual line segment  1   b  and that is formed on the downstream side end portion  24  side. In this case, the inclination angle  140  is larger than 0 degrees. That is, the first virtual line segment  121  is inclined with respect to the virtual line segment  1   b . More specifically, in the cross-section perpendicular to the longitudinal direction of the first crosspiece  21 , the first virtual line segment  121  is inclined with respect to the virtual line segment  1   b  such that the first direction from the upstream side end portion  23  to the downstream side end portion  24  is directed toward the rotation direction of the propeller fan  1  at a position in the cross-section. 
     The airflow blown out from the propeller fan  1  is a swirling flow. That is, the direction of airflow blown out from the propeller fan  1  is inclined with respect to the rotation axis  1   a  of the propeller fan  1 . Therefore, when the first virtual line segment  121  is inclined with respect to the virtual line segment  1   b  as described above, the airflow blown out from the propeller fan  1  easily flows along the first crosspieces  21 . If the airflow blown out from the propeller fan  1  can flow along the first crosspieces  21 , it is possible to reduce the ventilation resistance of the fan grille  20 . Further, if the airflow blown out from the propeller fan  1  can flow along the first crosspieces  21 , it is possible to prevent the airflow blown out from the propeller fan  1  from being directed away from the surface of the first crosspieces  21 , and to reduce disturbance of airflow. That is, if the airflow blown out from the propeller fan  1  can flow along the first crosspieces  21 , it is possible to reduce noise and energy loss that occur when driving the air-sending device  40 . 
     In the case where the air outlet  11  of the bell mouth  10  is axially symmetric with respect to the rotation axis  1   a  of the propeller fan  1 , the degree of inclination of the swirling flow with respect to the rotation axis  1   a  of the propeller fan  1  is constant. Therefore, in the case where the air outlet  11  of the bell mouth  10  is axially symmetric with respect to the rotation axis  1   a  of the propeller fan  1 , even if the inclination of the first virtual line segment  121  with respect to the virtual line segment  1   b  is constant at every position on the first crosspieces  21 , the airflow blown out from the propeller fan  1  can flow along the first crosspieces  21 . 
     However, as mentioned above, in the air-sending device  40  of Embodiment 1, the air outlet  11  of the bell mouth  10  is axially asymmetric with respect to the rotation axis  1   a  of the propeller fan  1 . Therefore, in the air-sending device  40  of Embodiment 1, the inclination of the swirling flow with respect to the rotation axis  1   a  of the propeller fan  1  varies with the position. Accordingly, in the air-sending device  40  of Embodiment 1, if the inclination of the first virtual line segment  121  with respect to the virtual line segment  1   b  is constant at every position on the first crosspieces  21 , the airflow blown out from the propeller fan  1  cannot flow along the first crosspieces  21  at some positions. In consideration of this, in the air-sending device  40  of Embodiment 1, the inclination of the first virtual line segment  121  with respect to the virtual line segment  1   b  is changed according to the position. 
     The following describes in detail how the airflow blown out from the propeller fan  1  flows, in the air-sending device  40  of Embodiment 1. The following also describes in detail how the inclination of the first virtual line segment  121  with respect to the virtual line segment  1   b  is changed according to the position. 
       FIG. 6  illustrates the air-sending device according to Embodiment 1 of the present disclosure, wherein the rotation axis and the air outlet of the bell mouth are projected on a virtual plane orthogonal to the rotation axis.  FIG. 7  is a view for explaining the distance between the rotation axis and the air outlet of the bell mouth, in the air-sending device according to Embodiment 1 of the present disclosure. 
     On the virtual plane illustrated in  FIG. 6 , a center point  100 , a second virtual line segment  122 , and a radial distance  130  are defined as follows. The center point  100  is the position of the rotation axis  1   a  of the propeller fan  1 . The second virtual line segment  122  is a virtual line segment connecting between the center point  100  and any one point on the edge  12  of the air outlet  11  of the bell mouth  10 . The radial distance  130  is the length of the second virtual line segment  122 . That is, the radial distance  130  is the distance between the rotation axis  1   a  of the propeller fan  1  and any one point on the edge  12  of the air outlet  11  of the bell mouth  10 . 
     The radial distance  130  varies as illustrated in  FIG. 7  as the second virtual line segment  122  rotates about the center point  100  in the rotation direction  4  of the propeller fan  1 . In other words, the radial distance  130  varies as illustrated in  FIG. 7  when any one point on the edge  12  of the air outlet  11  as an end of the second virtual line segment moves in the rotation direction  4  of the propeller fan  1 . 
     Specifically, the range from a point A to a point B illustrated in  FIG. 6  is the range of the constant portion  13  of the edge  12  of the air outlet  11 . As described above, the constant portion  13  has the shape of a circular arc about the rotation axis  1   a . Accordingly, in the range from the point A to the point B, the radial distance  130  is constant without varying. That is, in the range from the point A to the point B, the distance from the rotation axis  1   a  of the propeller fan  1  is constant. 
     The range from the point B to a point D illustrated in  FIG. 6  is the range of the varying portion  14  of the edge  12  of the air outlet  11 . As described above, the varying portion  14  has a linear shape when the varying portion  14  is viewed in the direction of the rotation axis  1   a . Accordingly, when the midpoint between the point B and the point C is defined as a point C, the radial distance  130  decreases in the range from the point B to the point C. That is, in the range from the point B to the point C, the distance from the rotation axis  1   a  of the propeller fan  1  decreases. Meanwhile, in the range from the point C to the point D, the radial distance  130  increases. That is, in the range from the point C to the point D, the distance from the rotation axis  1   a  of the propeller fan  1  increases. 
     The range from the point D to a point E illustrated in  FIG. 6  is the range of the constant portion  13  of the edge  12  of the air outlet  11 . Accordingly, in the range from the point D to the point E, the radial distance  130  is constant without varying, as in the range from the point A to the point B. In the subsequent varying portions  14  of the edge  12  of the air outlet  11 , the radial distance  130  varies as in the range from the point B to the point D. In the subsequent constant portions  13  of the edge  12  of the air outlet  11 , the radial distance  130  is constant as in the range from the point A to the point B. 
     In the air-sending device  40  according to Embodiment 1, since the edge  12  of the air outlet  11  of the bell mouth  10  has the shape described above, the inclination of the airflow blown out from the propeller fan  1  with respect to the rotation axis  1   a  varies in the manner describe below. 
       FIG. 8  is a diagram for explaining the state of a swirling flow of the air-sending device according to Embodiment 1 of the present disclosure. Note that  FIG. 8  illustrates the air-sending device  40 , with the fan grille  20  removed, as viewed from the air outlet  11  side of the bell mouth  10 . 
     When the propeller fan  1  rotates, the airflow around each blade  3  is introduced from the leading edge  5  side of the blade  3  and is discharged from the trailing edge  6  of the blade  3 . The direction of the airflow passing between the blades  3  is changed due to the inclination and camber of each blade  3  when the airflow flows along the blade  3 , and a static pressure thereof increases due to a change in momentum. The airflow blown out from the propeller fan  1  is inclined toward the rotation direction  4  and radially outward with respect to the direction of the rotation axis  1   a , as the blade  3  rotates. That is, the airflow blown out from the propeller fan  1  is a swirling flow. 
     In the air-sending device  40  of Embodiment 1, the air outlet  11  of the bell mouth  10  is axially asymmetric with respect to the rotation axis  1   a  of the propeller fan  1 . Therefore, in the air-sending device  40  of Embodiment 1, the following phenomenon occurs to the airflow blown out from the propeller fan  1 . 
     As described above, in the range from the point B to the point C of the varying portion  14  of the edge  12  of the air outlet  11  of the bell mouth  10 , the radial distance  130  decreases. That is, in the range from the point B to the point C, a side wall  15  of the edge  12  of the air outlet  11  becomes closer to the rotation axis  1   a  of the propeller fan  1 , toward the rotation direction  4  of the propeller fan  1 . Therefore, the blown-out airflow from the propeller fan  1  swirling and spreading radially outward is corrected to the direction of the rotation axis  1   a , in the range from the point B to the point C on the side wall  15  of the edge  12  of the air outlet  11 . Accordingly, as illustrated as airflow  91  in  FIG. 8 , in the range from the point B to the point C, the component in the direction of the rotation axis  1   a  of the blown-out airflow from the propeller fan  1  becomes greater, so that the inclination of the airflow with respect to the rotation axis  1   a  is reduced. 
     Meanwhile, as described above, in the range from the point C to the point D of the varying portion  14  of the edge  12  of the air outlet  11  of the bell mouth  10 , the radial distance  130  increases. That is, in the range from the point C to the point D, the side wall  15  of the edge  12  of the air outlet  11  becomes farther from the rotation axis  1   a  of the propeller fan  1 , toward the rotation direction  4  of the propeller fan  1 . This allows the blown-out airflow from the propeller fan  1  swirling and spreading radially outward to easily spread radially outward. Accordingly, as illustrated as airflow  92  in  FIG. 8 , in the range from the point C to the point D, the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  is increased. 
     In consideration of this, according to the air-sending device  40  of Embodiment 1, the inclination angle  140 , which is the inclination of the first virtual line segment  121  with respect to the virtual line segment  1   b , is changed according to the position as described below. 
       FIGS. 9 and 10  illustrate the air-sending device according to Embodiment 1 of the present disclosure; wherein the rotation axis; the air outlet of the bell mouth, and the plurality of first crosspieces are projected on a virtual plane orthogonal to the rotation axis.  FIG. 11  is a cross-sectional view of the first crosspieces at an eighth point and a ninth point of  FIG. 9 , illustrating cross-sections of the first crosspieces perpendicular to the longitudinal direction of the first crosspieces at the eighth point and the ninth point. Note that  FIG. 11( a )  is a cross-sectional view of the first crosspiece  21  at the eighth point illustrated in  FIG. 9 .  FIG. 11( b )  is a cross-sectional view of the first crosspiece  21  at the ninth point illustrated in  FIG. 9 . 
     On the virtual plane illustrated in  FIG. 9 , a first point  101 , a second point  102 , a third point  103 , a fourth point  104 , a fifth point  105 , a sixth point  106 , a first radial distance  131 , a seventh point  107 , a third virtual line segment  123 , a fourth virtual line segment  124 , an eighth point  108 , and a ninth point  109  are defined as follows. 
     The first point  101  is a point that is on the edge  12  of the air outlet  11 , and from which the radial distance  130  decreases when the second virtual line segment  122  rotates about the center point  100  in the rotation direction  4  of the propeller fan  1 . That is, the first point  101  is, for example, the point B of  FIG. 6 . The second point  102  is a point that is on the edge  12  of the air outlet  11 , and from which the radial distance  130  increases when the second virtual line segment  122  rotates about the center point  100  in the rotation direction  4  of the propeller fan  1  past the first point  101 . That is, the second point  102  is, for example, the point C of  FIG. 6 . The third point  103  is a point that is on the edge  12  of the air outlet  11 , and from which the radial distance  130  no longer increases when the second virtual line segment  122  rotates about the center point  100  in the rotation direction  4  of the propeller fan  1  past the second point  102 , That is, the third point  103  is, for example, the point D of  FIG. 6 . 
     The fourth point  104  is a point that is on the edge  12  of the air outlet  11 , that is located before the second point  102  and after the first point  101  in the rotation direction  4  of the propeller fan  1 , and that is a midpoint between the first point  101  and the second point  102 . The fifth point  105  is a point that is on the edge  12  of the air outlet  11 , that is located before the third point  103  and after the second point  102  in the rotation direction  4  of the propeller fan  1 , and that is a midpoint between the second point  102  and the third point  103 . The sixth point  106  is a point that is on the edge  12  of the air outlet  11  and that is located before the fourth point  104  and after the first point  101  in the rotation direction  4  of the propeller fan  1 . The first radial distance  131  is the radial distance  130  between the center point  100  and the sixth point  106 . 
     The seventh point  107  is a point that is on the edge  12  of the air outlet  11 , and that is located before the third point  103  and after the fifth point  105  in the rotation direction  4  of the propeller fan  1 , and the radial distance  130  is the first radial distance  131 . The third virtual line segment  123  is a virtual line segment connecting between the center point  100  and the sixth point  106 . The fourth virtual line segment  124  is a virtual line segment connecting between the center point  100  and the seventh point  107 . The eighth point  108  is a point of intersection of a virtual circle  150  having its center at the center point  100  and having any radius and the third virtual line segment  123 , of the plurality of first crosspieces  21 . The ninth point  109  is a point of intersection of the virtual circle  150  and the fourth virtual line segment  124 , of the plurality of first crosspieces  21 . 
     When the above definitions are applied, the eighth point  108  of the plurality of first crosspieces  21  is any one point on the portions of the plurality of first crosspieces  21  that are present in an area P 1  illustrated in  FIG. 10 . Further, the ninth point  109  of the plurality of first crosspieces  21  is a point on the portions of the plurality of first crosspieces  21  that are present in an area Q 1  illustrated in  FIG. 10 , and satisfies the above definitions. Note that the area P 1  is an area defined by a virtual line segment connecting between the center point  100  and the first point  101 , a portion between the first point  101  and the fourth point  104  in the varying portion  14  of the edge  12  of the air outlet  11 , and a virtual line segment connecting between the center point  100  and the fourth point  104 . Further, the area Q 1  is an area defined by a virtual line segment connecting between the center point  100  and the fifth point  105 , a portion between the fifth point  105  and the third point  103  in the varying portion  14  of the edge  12  of the air outlet  11 , and a virtual line segment connecting between the center point  100  and the third point  103 . 
     The area P 1  has only to include at least the range of the area P 1  illustrated in  FIG. 10 . Accordingly, the area P 1  may include an area located before the area P 1  illustrated in  FIG. 10  in the rotation direction  4  of the propeller fan  1 . For example, in  FIG. 10 , a midpoint between the point A and the point B illustrated in  FIG. 6  on the edge  12  of the air outlet  11  is connected to the center point  100  by a virtual line segment. Then, the area P 1  may be the area between this virtual line segment and a virtual line segment connecting between the center point  100  and the fourth point  104 . Similarly, the area Q 1  has only to include at least the range of the area Q 1  illustrated in  FIG. 10 . Accordingly, the area Q 1  may include an area located after the area Q 1  illustrated in  FIG. 10  in the rotation direction  4  of the propeller fan  1 . For example, in  FIG. 10 , a midpoint between the point D and the point E illustrated in  FIG. 6  on the edge  12  of the air outlet  11  is connected to the center point  100  by a virtual line segment. Then, the area Q 1  may be the area between this virtual line segment and a virtual line segment connecting between the center point  100  and the fifth point  105 . 
     As is understood from the description of  FIGS. 6 to 8 , in the area P 1  of  FIG. 10 , the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  is smaller compared to that in the area Q 1  of  FIG. 10 . In other words, in the area Q 1  of  FIG. 10 , the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  is larger compared to that in the area P 1  of  FIG. 10 . 
     In consideration of this, in Embodiment 1, as illustrated in  FIG. 11 , the inclination angle  140  at the eighth point  108  present in the area P 1  is set to be smaller than the inclination angle  140  at the ninth point  109  present in the area Q 1 . By setting the inclination angle  140  of the first crosspieces  21  in this manner, the inclination angle  140  can be reduced in the area P 1  where the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  is small. Meanwhile, the inclination angle  140  can be increased in the area Q 1  where the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  is large. 
     Thus, according to the air-sending device  40  of Embodiment 1, the airflow blown out from the propeller fan  1  can flow along the first crosspieces  21 , in the area P 1  and the area Q 1  that differ in the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a . Therefore, according to the air-sending device  40  of Embodiment 1, it is possible to reduce the ventilation resistance of the fan grille  20  as compared to the related art. Further, according to the air-sending device  40  of Embodiment 1, it is possible to prevent the airflow blown out from the propeller fan  1  from being directed away from the surface of the first crosspieces  21  as compared to the related art, and to reduce disturbance of airflow as compared to the related art. That is, according to the air-sending device  40  of Embodiment 1, it is possible to reduce noise and energy loss that occur when driving the air-sending device  40  as compared to the related art. 
     Note that in Embodiment 1, the inclination angle  140  at the portions of the plurality of first crosspieces  21  that are present in the area P 1  is constant. Also, the inclination angle  140  at the portions of the plurality of first crosspieces  21  that are present in the area Q 1  is constant. 
     Embodiment 1 aims to further reduce noise and energy loss that occur when driving the air-sending device  40 . To this end, the inclination angle  140  at the portions of the plurality of first crosspieces  21  that are present in an area P 2  illustrated in  FIG. 10  and the inclination angle  140  at the portions of the plurality of first crosspieces  21  that are present in an area Q 2  illustrated in  FIG. 10  are set as described below. Note that the area P 2  is an area defined by a virtual line segment connecting between the center point  100  and the fourth point  104 , a portion between the fourth point  104  and the second point  102  in the varying portion  14  of the edge  12  of the air outlet  11 , and a virtual line segment connecting between the center point  100  and the second point  102 . Further, the area Q 2  is an area defined by a virtual line segment connecting between the center point  100  and the second point  102 , a portion between the second point  102  and the fifth point  105  in the varying portion  14  of the edge  12  of the air outlet  11 , and a virtual line segment connecting between the center point  100  and the fifth point  105 . 
       FIG. 12  illustrates the air-sending device according to Embodiment 1 of the present disclosure, wherein the rotation axis, the air outlet of the bell mouth, and a plurality of first crosspieces are projected on a virtual plane orthogonal to the rotation axis. 
     On the virtual plane illustrated in  FIG. 12 , a tenth point  110 , a second radial distance  132 , an eleventh point  111 , a fifth virtual line segment  125 , a sixth virtual line segment  126 , a twelfth point  112 , and a thirteenth point  113  are defined as follows. 
     The tenth point  110  is a point that is on the edge  12  of the air outlet  11 , and that is located before the second point  102  and after the fourth point  104  in the rotation direction  4  of the propeller fan  1 . The second radial distance  132  is the radial distance  130  between the center point  100  and the tenth point  110 . The eleventh point  111  is a point that is on the edge  12  of the air outlet  11 , and that is located before the fifth point  105  and after the second point  102  in the rotation direction  4  of the propeller fan  1 , and the radial distance  130  is the second radial distance  132 . The fifth virtual line segment  125  is a virtual line segment connecting between the center point  100  and the tenth point  110 . The sixth virtual line segment  126  is a virtual line segment connecting between the center point  100  and the eleventh point  111 . The twelfth point  112  is a point of intersection of the virtual circle  150  and the fifth virtual line segment  125 , of the plurality of first crosspieces  21 . The thirteenth point  113  is a point of intersection of the virtual circle  150  and the sixth virtual line segment  126 , of the plurality of first crosspieces  21 . 
     When the above definitions are applied, the twelfth point  112  of the plurality of first crosspieces  21  is any one point on the portions of the plurality of first crosspieces  21  that are present in the area P 2  illustrated in  FIG. 10 . Further, the thirteenth point  113  of the plurality of first crosspieces  21  is a point on the portions of the plurality of first crosspieces  21  that are present in the area Q 2  illustrated in  FIG. 10 , and satisfies the above definitions. 
     As is understood from the description of  FIGS. 6 to 8 , in the area P 2  of  FIG. 10 , the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  is smaller compared to that in the area Q 2  of  FIG. 10 . In other words, in the area Q 2  of  FIG. 10 , the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  is larger compared to that in the area P 2  of  FIG. 10 . 
     In consideration of this, in Embodiment 1, the inclination angle  140  at the twelfth point  112  present in the area P 2  is set to be smaller than that at the thirteenth point  113  present in the area Q 2 . By setting the inclination angle  140  of the first crosspieces  21  in this manner, the inclination angle  140  can be reduced in the area P 2  where the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  is small. Meanwhile, the inclination angle  140  can be increased in the area Q 2  where the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  is large. 
     Thus, according to the air-sending device  40  of Embodiment 1, the airflow blown out from the propeller fan  1  can flow along the first crosspieces  21 , in the area P 2  and the area Q 2  that differ in the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  as well. Therefore, according to the air-sending device  40  of Embodiment 1, it is possible to further reduce the ventilation resistance of the fan grille  20 . Further, according to the air-sending device  40  of Embodiment 1, it is possible to further prevent the airflow blown out from the propeller fan  1  from being directed away from the surface of the first crosspieces  21 , and to further reduce disturbance of airflow. That is, according to the air-sending device  40  of Embodiment 1, it is possible to further reduce noise and energy loss that occur when driving the air-sending device  40 . 
     Note that in Embodiment 1, the inclination angle  140  at the twelfth point  112  present in the area P 2  is equal to the inclination angle  140  at the eighth point  108  present in the area P 1 . Further, the inclination angle  140  at the portions of the plurality of first crosspieces  21  that are present in the area P 2  illustrated in  FIG. 10  is constant. Further, the inclination angle  140  at the thirteenth point  113  present in the area Q 2  is equal to the inclination angle  140  at the ninth point  109  present in the area Q 1 . Also, the inclination angle  140  at the portions of the plurality of first crosspieces  21  that are present in the area Q 2  illustrated in  FIG. 10  is constant. 
     Embodiment 1 does not particularly mention the configuration of the plurality of second crosspieces  22 . The plurality of second crosspieces  22  may have the same configuration as the plurality of first crosspieces  21  described above. Thus, it is possible to further reduce the ventilation resistance and disturbance of airflow, and to further reduce noise and energy loss that occur when driving the air-sending device  40 . 
     Embodiment 2 
     The shape of the air outlet  11  of the bell mouth  10  illustrated in Embodiment 1 is merely an example. By setting the inclination angle of the first crosspieces  21  as in Embodiment 1 for the air outlet  11  of the bell mouth  10  that is axially asymmetric with respect to the rotation axis  1   a  of the propeller fan  1 , it is possible to reduce noise and energy loss that occur when driving the air-sending device  40  as compared to the related art. The air outlet  11  of the bell mouth  10  may have the following shape, for example. It should be noted that, in Embodiment 2, items not specifically described are the same as those of Embodiment 1, and the same functions and configurations as those of Embodiment 1 are denoted by the same reference signs. 
       FIG. 13  illustrates an air-sending device according to Embodiment 2 of the present disclosure, wherein a rotation axis and an air outlet of a bell mouth are projected on a virtual plane orthogonal to the rotation axis.  FIG. 14  is a view for explaining the distance between the rotation axis and the air outlet of the bell mouth, in the air-sending device according to Embodiment 2 of the present disclosure.  FIG. 15  illustrates the air-sending device according to Embodiment 2 of the present disclosure, wherein the rotation axis, the air outlet of the bell mouth, and a plurality of first crosspieces are projected on a virtual plane orthogonal to the rotation axis. 
     The air-sending device  40  of Embodiment 2 is different from the air-sending device  40  of Embodiment 1 in the shape of the varying portion  14  of the edge  12  of the air outlet  11  of the bell mouth  10 . In Embodiment 1, the varying portion  14  has a linear shape when the varying portion  14  is viewed in the direction of the rotation axis  1   a . Meanwhile, in Embodiment 2, the varying portion  14  has a circular-arc shape when the varying portion  14  is viewed in the direction of the rotation axis  1   a . Further, the curvature radius of the varying portion  14  of Embodiment 2 is greater than the curvature radius of the constant portion  13 . 
     As illustrated in  FIG. 14 , in the air-sending device  40  of Embodiment 2 as well, when any one point on the edge  12  of the air outlet  11  as an end of the second virtual line segment moves in the rotation direction of the propeller fan  1 , namely, the rotation direction  4 , the radial distance  130  varies in the same manner as in Embodiment 1. 
     Specifically, as illustrated in  FIG. 13 , the varying portion  14  is the range from a point F to a point H. When the midpoint between the point F and the point H is defined as a point G, the radial distance  130  decreases in the range from the point F to the point G. That is, in the range from the point F to the point G, the distance from the rotation axis  1   a  of the propeller fan  1  decreases. Meanwhile, in the range from the point G to the point H, the radial distance  130  increases. That is, in the range from the point G to the point H, the distance from the rotation axis  1   a  of the propeller fan  1  increases. 
     Therefore, in the air-sending device  40  of Embodiment 2 as well, the airflow blown out from the propeller fan  1  varies in the same manner as in Embodiment 1, due to the influence of the varying portion  14 . Accordingly, in the range from the point F to the point G where the radial distance  130  decreases, the component in the direction of the rotation axis  1   a  of the blown-out airflow from the propeller fan  1  becomes greater, so that the inclination of the airflow with respect to the rotation axis  1   a  is reduced. Meanwhile, in the range from the point G to the point H where the radial distance  130  increases, the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  is increased. 
     Accordingly, as illustrated in  FIG. 15 , in the air-sending device  40  of Embodiment 2 as well, the eighth point  108  and the ninth point  109  are defined as in Embodiment 1. Note that in Embodiment 2, the first point  101  is, for example, the point F of  FIG. 13 . The second point  102  is, for example, the point G of  FIG. 13 . The third point is, for example, the point H of  FIG. 13 . 
     Further, in the air-sending device  40  of Embodiment 2 as well, the inclination angle  140  at the eighth point  108  is set to be smaller than the inclination angle  140  at the ninth point  109 . By setting the inclination angle  140  of the first crosspieces  21  in this manner, the inclination angle  140  can be reduced in the area P 1  where the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  is small, as in Embodiment 1. Meanwhile, the inclination angle  140  can be increased in the area Q 1  where the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  is large. Note that in Embodiment 2, the inclination angle  140  at the portions of the plurality of first crosspieces  21  that are present in the area P 1  is constant. Also, the inclination angle  140  at the portions of the plurality of first crosspieces  21  that are present in the area Q 1  is constant. 
     Thus, according to the air-sending device  40  of Embodiment 2, the airflow blown out from the propeller fan  1  can flow along the first crosspieces  21 , in the area P 1  and the area Q 1  that differ in the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a , as in Embodiment 1. Therefore, according to the air-sending device  40  of Embodiment 2, it is possible to reduce the ventilation resistance of the fan grille  20  as compared to the related art, as in Embodiment 1. Further; according to the air-sending device  40  of Embodiment 2, it is possible to prevent the airflow blown out from the propeller fan  1  from being directed away from the surface of the first crosspieces  21  as compared to the related art, and to reduce disturbance of airflow as compared to the related art, as in Embodiment 1. That is, according to the air-sending device  40  of Embodiment 2, it is possible to reduce noise and energy loss that occur when driving the air-sending device  40  as compared to the related art, as in Embodiment 1. 
     Note that, as in Embodiment 1, the twelfth point  112  and the thirteenth point  113  may be defined, and the inclination angle  140  at the twelfth point  112  may be set to be smaller than that at the thirteenth point  113 . Thus, the airflow blown out from the propeller fan  1  can flow along the first crosspieces  21 , in the area P 2  and the area Q 2  that differ in the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  as well. Accordingly, it is possible to further reduce noise and energy loss that occur when driving the air-sending device  40 . 
     Embodiment 3 
     The inclination angle  140  may vary with the position, at the portions of the plurality of first crosspieces  21  that are present in the area P 1  and the area P 2 . Also, the inclination angle  140  may vary with the position, at the portions of the plurality of first crosspieces  21  that are present in the area Q 1  and the area Q 2 . It should be noted that, in Embodiment 3, items not specifically described are the same as those of Embodiment 1 or Embodiment 2, and the same functions and configurations as those of Embodiment 1 or Embodiment 2 are denoted by the same reference signs. 
       FIG. 16  illustrates an example of changes in the inclination angle, in an air-sending device according to Embodiment 3 of the present disclosure. The solid line illustrated in  FIG. 16  indicates changes in the inclination angle  140  of the air-sending device  40  of Embodiment 3. The dashed line illustrated in  FIG. 16  indicates changes in the inclination angle  140  of the air-sending device  40  of Embodiment 1. 
     As is clear from the dashed line from the first point  101  to the second point  102  in  FIG. 16 , in the air-sending device  40  of Embodiment 1, the inclination angle  140  is constant at the portions of the plurality of first crosspieces  21  that are present in the area P 1  and the area P 2 . Also, as is clear from the dashed line from the second point  102  to the third point  103  in  FIG. 16 , in the air-sending device  40  of Embodiment 1, the inclination angle  140  is constant at the portions of the plurality of first crosspieces  21  that are present in the area Q 1  and the area Q 2 . 
     Meanwhile, as is clear from the solid line from the first point  101  to the second point  102  in  FIG. 16 , in the air-sending device  40  of Embodiment 3, the inclination angle  140  varies at the portions of the plurality of first crosspieces  21  that are present in the area P 1  and the area P 2  when the inclination angle  140  is viewed in the rotation direction  4  of the propeller fan  1 . Note that the way in which the inclination angle  140  increases and decreases in  FIG. 16  is merely an example. Also, as is clear from the solid line from the second point  102  to the third point  103  in  FIG. 16 , in the air-sending device  40  of Embodiment 3, the inclination angle  140  varies at the portions of the plurality of first crosspieces  21  that are present in the area Q 1  and the area Q 2  when the inclination angle  140  is viewed in the rotation direction  4  of the propeller fan  1 . Note that the way in which the inclination angle  140  increases and decreases in  FIG. 16  is merely an example. 
     In the air-sending device  40  configured as in Embodiment 3 as well, by setting the inclination angle  140  at the eighth point  108  to be smaller than the inclination angle  140  at the ninth point  109 , it is possible to reduce noise and energy loss that occur when driving the air-sending device  40 , as compared to the related art. Also, in the air-sending device  40  configured as in Embodiment 3 as well, by setting the inclination angle  140  at the twelfth point  112  to be smaller than that at the thirteenth point  113 , it is possible to further reduce noise and energy loss that occur when driving the air-sending device  40 . 
     As described above, in the range where the side wall  15  becomes closer to the rotation axis  1   a  of the propeller fan  1  in the varying portion  14  of the edge  12  of the air outlet  11 , the flow of the blown-out airflow from the propeller fan  1  is forced by the side wall  15 , so that the inclination of the airflow with respect to the rotation axis  1   a  is reduced. Here, in the range where the side wall  15  becomes closer to the rotation axis  1   a  of the propeller fan  1  in the varying portion  14  of the edge  12  of the air outlet  11 , the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  is not uniform. The inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  varies with the shape of the varying portion  14  of the edge  12  of the air outlet  11 . Further, as described above, in the range where the side wall  15  becomes farther from the rotation axis  1   a  of the propeller fan  1  in the varying portion  14  of the edge  12  of the air outlet  11 , the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  increases. In the range where the side wall  15  becomes farther from the rotation axis  1   a  of the propeller fan  1  in the varying portion  14  of the edge  12  of the air outlet  11  as well, the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  varies with the shape of the varying portion  14  of the edge  12  of the air outlet  11 . 
     In consideration of this, in the air-sending device  40  of Embodiment 3, the inclination angle  140  varies at the portions of the plurality of first crosspieces  21  that are present in the area P 1  and the area P 2  when the inclination angle  140  is viewed in the rotation direction of the propeller fan  1 . Also, in the air-sending device  40  of Embodiment 3, the inclination angle  140  varies at the portions of the plurality of first crosspieces  21  that are present in the area Q 1  and the area Q 2  when the inclination angle  140  is viewed in the rotation direction of the propeller fan  1 . With this configuration, the airflow blown out from the propeller fan  1  can flow further along the first crosspieces  21 , so that it is possible to further reduce the ventilation resistance and disturbance of airflow. Accordingly, by configuring the air-sending device  40  as in Embodiment 3, it is possible to further reduce noise and energy loss that occur when driving the air-sending device  40 . 
       FIG. 17  illustrates another example of changes in the inclination angle, in an air-sending device according to Embodiment 3 of the present disclosure. 
     In  FIG. 16 , the inclination angle  140  at the portions of the plurality of first crosspieces  21  that are present in the area P 1  and the area P 2  varies gradually. 
     However, for example, as illustrated in  FIG. 17 , the inclination angle  140  at the portions of the plurality of first crosspieces  21  that are present in the area P 1  and the area P 2  may vary in a stepwise manner. Similarly, for example, as illustrated in  FIG. 17 , the inclination angle  140  at the portions of the plurality of first crosspieces  21  that are present in the area Q 1  and the area Q 2  may vary in a stepwise manner. 
     Embodiment 4 
     In the air-sending devices  40  of Embodiments 1 to 3, the inclination angle  140  of the first crosspieces  21  may be changed in accordance with the distance from the rotation axis  1   a . Then, it is possible to further reduce noise and energy loss that occur when driving the air-sending device  40 . It should be noted that, in Embodiment 4, items not specifically described are the same as those of any of Embodiments 1 to 3, and the same functions and configurations as those of any of Embodiments 1 to 3 are denoted by the same reference signs. 
       FIG. 18  illustrates an air-sending device according to Embodiment 4 of the present disclosure, wherein a rotation axis, an air outlet of a bell mouth, and a plurality of first crosspieces are projected on a virtual plane orthogonal to the rotation axis.  FIG. 19  is a cross-sectional view of the first crosspieces at a fifteenth point and a sixteenth point of  FIG. 18 , illustrating cross-sections of the first crosspieces perpendicular to the longitudinal direction of the first crosspieces at the fifteenth point and the sixteenth point. Note that  FIG. 19( a )  is a cross-sectional view of the first crosspiece  21  at the fifteenth point illustrated in  FIG. 18 .  FIG. 19( b )  is a cross-sectional view of the first crosspiece  21  at the sixteenth point illustrated in  FIG. 18 . 
     On the virtual plane illustrated in  FIG. 18 , a fourteenth point  114 , a seventh virtual line segment  127 , a fifteenth point  115 , and a sixteenth point  116  are defined as follows. The fourteenth point  114  is a point that is on the edge  12  of the air outlet  11 , and that is located before the third point  103  and after the first point  101  in the rotation direction  4  of the propeller fan  1 . The seventh virtual line segment  127  is a virtual line segment connecting between the center point  100  and the fourteenth point  114 . The fifteenth point  115  is any one point of intersection with the seventh virtual line segment  127  of the plurality of first crosspieces  21 . The sixteenth point  116  is a point of intersection with the seventh virtual line segment  127  of the plurality of first crosspieces  21 , at a position farther from the center point  100  than the fifteenth point  115 . 
     When the above definitions are applied, in the air-sending device  40  of Embodiment 4, the inclination angle  140  at the sixteenth point  116  is larger than the inclination angle  140  at the fifteenth point  115 , as illustrated in  FIG. 19 . That is, in the air-sending device  40  of Embodiment 4, the inclination angle  140  at a point of the plurality of first crosspieces  21  on a virtual line segment connecting between any point on the varying portion  14  of the edge  12  and the center point  100  is greater when the point is farther from the center point  100 , that is, the rotation axis  1   a.    
     The speed of the swirling flow blown out from the propeller fan  1  is higher when the distance from the rotation axis  1   a  is greater, Therefore, the inclination of the airflow blown out of the propeller fan  1  with respect to the rotation axis  1   a  is greater when the distance from the rotation axis  1   a  is greater. Accordingly, by setting the inclination angle  140  of the first crosspieces  21  as in Embodiment 4, it is possible to make the airflow blown out from the propeller fan  1  flow further along the first crosspieces  21 , and to further reduce the ventilation resistance and disturbance of airflow. Accordingly, by configuring the air-sending device  40  as in Embodiment 4, it is possible to further reduce noise and energy loss that occur when driving the air-sending device  40 . 
     Embodiment 5 
     It is possible to further reduce noise and energy loss that occur when driving the air-sending device  40 , by adopting the configuration of the inclination angle  140  of the first crosspieces  21  illustrated in Embodiment 5 to the air-sending device  40  of any of Embodiments 1 to 4. It should be noted that, in Embodiment 5, items not specifically described are the same as those of any of Embodiments 1 to 4, and the same functions and configurations as those of any of Embodiments 1 to 4 are denoted by the same reference signs. 
       FIG. 20  illustrates an air-sending device according to Embodiment 5 of the present disclosure, wherein a rotation axis, an air outlet of a bell mouth, and a plurality of first crosspieces are projected on a virtual plane orthogonal to the rotation axis.  FIG. 21  is a cross-sectional view of the first crosspieces at a seventeenth point and an eighteenth point of  FIG. 20 , illustrating cross-sections of the first crosspieces perpendicular to the longitudinal direction of the first crosspieces at the seventeenth point and the eighteenth point. Note that  FIG. 21( a )  is a cross-sectional view of the first crosspiece  21  at the seventeenth point illustrated in  FIG. 20 .  FIG. 21( b )  is a cross-sectional view of the first crosspiece  21  at the eighteenth point illustrated in  FIG. 20 .  FIGS. 21( a ) and 21( b )  illustrate the cross-sections of the first crosspieces  21  when viewed from the same direction.  FIGS. 21( a ) and 21( b )  illustrate the cross-sections of the first crosspieces  21  when viewed from the lower side of the drawing. That is,  FIG. 21( a )  is an X-X cross-sectional view of  FIG. 20 . Further,  FIG. 21( b )  is a Y-Y cross-sectional view of  FIG. 20 . 
     On the virtual plane illustrated in  FIG. 20 , a seventeenth point  117  and an eighteenth point  118  are defined as follows. The seventeenth point  117  is any one point of the plurality of first crosspieces  21 . The eighteenth point  118  is a point symmetric to the seventeenth point  117  with respect to a center of symmetry at the center point  100 , of the plurality of first crosspieces  21 . 
     When the above definitions are used, the inclination directions at the seventeenth point  117  and the eighteenth point  118  are opposite when the seventeenth point  117  and the eighteenth point  118  are viewed from the same direction. 
     As described above, the airflow blown out from the propeller fan  1  is a swirling flow. Therefore, when the blown-out airflows from the propeller fan  1  passing through two points symmetric with respect to the center point  100  are viewed from the same direction, the blown-out airflows from the propeller fan  1  are inclined in opposite directions with respect to the rotation axis  1   a . Accordingly, by setting the inclination angle  140  of the first crosspieces  21  as in Embodiment 5, it is possible to make the airflow blown out from the propeller fan  1  flow further along the first crosspieces  21 , and to further reduce the ventilation resistance and disturbance of airflow. Therefore, by configuring the air-sending device  40  as in Embodiment 5, it is possible to further reduce noise and energy loss that occur when driving the air-sending device  40 . 
     Note that the inclination angle  140  at the seventeenth point  117  and the inclination angle  140  at the eighteenth point  118  do not have to be equal. The inclination angle  140  at the seventeenth point  117  may be appropriately determined in accordance with the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  when passing through the seventeenth point  117 . The inclination angle  140  at the eighteenth point  118  may be appropriately determined in accordance with the inclination of the blown-out airflow from the propeller fan  1  with respect to the rotation axis  1   a  when passing through the eighteenth point  118 . 
     For example, at the seventeenth point  117  illustrated in  FIG. 20 , the blown-out airflow from the propeller fan  1  is affected by the varying portion  14  of the edge  12 . Specifically, the flow of the blown-out airflow from the propeller fan  1  passing through the seventeenth point  117  is forced by the side wall  15 , so that the inclination of the airflow with respect to the rotation axis  1   a  is smaller than the blown-out airflow from the propeller fan  1  passing through the eighteenth point  118 . Meanwhile, at the eighteenth point  118  illustrated in  FIG. 20 , the blown-out airflow from the propeller fan  1  is not affected by the varying portion  14  of the edge  12 . Therefore, the inclination of the blown-out airflow from the propeller fan  1  passing through the eighteenth point  118  with respect to the rotation axis  1   a  is smaller than the blown-out airflow from the propeller fan  1  passing through the seventeenth point  117 . Accordingly, in  FIG. 21 , the inclination angle  140  at the seventeenth point  117  is smaller than the inclination angle  140  at the eighteenth point  118 . 
     Embodiment 6 
     In the case where the fan grille  20  of any of Embodiments 1 to 5 is manufactured to have the configuration of Embodiment 6, another advantage is obtained in that the fan grille  20  is easily manufactured, in addition to the advantages of Embodiments 1 to 5. It should be noted that, in Embodiment 6, items not specifically described are the same as those of any of Embodiments 1 to 5, and the same functions and configurations as those of any of Embodiments 1 to 5 are denoted by the same reference signs. 
       FIG. 22  is an enlarged perspective view illustrating a part of a fan grille of an air-sending device according to Embodiment 6 of the present disclosure.  FIG. 23  illustrates the air-sending device according to Embodiment 6 of the present disclosure, wherein a rotation axis, an air outlet of a bell mouth, and the fan grille are projected on a virtual plane orthogonal to the rotation axis.  FIG. 23  is a view for explaining the area P 1  and the area Q 1  in Embodiment 6. 
     In the fan grille  20  of the air-sending device  40  of Embodiment 6, the inclination angle  140  of any one of the plurality of first crosspieces  21  is constant between adjacent second crosspieces  22 . Specifically, in  FIG. 22 , each of the first crosspieces  21  extends diagonally upward and rightward in the drawing. Referring to one of the first crosspieces  21 , the first crosspiece  21  includes a plurality of crosspiece portions  21   a  that are divided at the positions of the second crosspieces  22 . Further, referring to any one of the plurality of crosspiece portions  21   a , the crosspiece portion  21   a  is configured such that the inclination angle  140  does not vary. 
     In the case of manufacturing the fan grille  20  of any of Embodiments 1 to 5, referring to each of the first crosspieces  21 , the first crosspiece  21  is configured such that the inclination angle  140  varies with the position. In this case, in each of the first crosspieces  21  of Embodiment 6, the inclination angle  140  differs between the crosspiece portions  21   a  such that the inclination angle  140  is changed at intersections with the second crosspieces  22 . Note that similar to each first crosspiece  21 , each second crosspiece  22  of Embodiment 6 has an elongated shape in the cross-section perpendicular to the longitudinal direction. The inclination angle  140  of each second crosspiece  22  of Embodiment 6 is, for example, 0 degrees. 
     To make the inclination angle  140  vary with the position on each first crosspiece  21 , the first crosspiece  21  may be twisted such that the inclination angle  140  varies continuously. However, this configuration makes it difficult to manufacture the fan grille  20 . Specifically, the fan grille  20  is manufactured by, for example, injection molding of resin. Thus, in the case of the configuration in which the first crosspiece  21  is twisted such that the inclination angle  140  varies continuously, the structure of a mold portion that molds the first crosspiece  21  becomes complex. 
     Also, to make the inclination angle  140  vary with the position on each first crosspiece  21 , the first crosspiece  21  may include the plurality of crosspiece portions  21   a  as in Embodiment 6 such that the inclination angle  140  differs between the crosspiece portions  21   a . In this case, if the inclination angle  140  is changed at positions other than the intersections with the second crosspieces  22 , the ends of the adjacent crosspiece portions  21   a  need to be directly connected to each other. However, if the ends of the adjacent crosspiece portions  21   a  are directly connected to each other, the area of the connection portion is reduced. Therefore, if the ends of the adjacent crosspiece portions  21   a  are directly connected to each other, the function of preventing foreign matter from entering from the outside may be impaired due to insufficient strength at the connection portion. 
     In the fan grille  20  of Embodiment 6, each end of each crosspiece portion  21   a  is connected to a side surface of one of the second crosspieces  22 . Therefore, in the fan grille  20  of Embodiment 6, the area of each connection portion is increased. For example, the entire surface of the crosspiece portion  21   a  is connected to the side surface of the second crosspiece  22 . Therefore, in the fan grille  20  of Embodiment 6, the strength of each connection portion is prevented from being insufficient. Further, in the fan grille  20  of Embodiment 6, referring to any one of the plurality of crosspiece portions  21   a , the inclination angle  140  of the crosspiece portion  21   a  does not vary. Therefore, the structure of a mold portion that molds the crosspiece portion  21   a  does not become complex. Accordingly, when the fan grille  20  is configured as in Embodiment 6, the fan grille  20  is easily manufactured. 
     In the case where the fan grille  20  is configured as in Embodiment 6, if there is no connection portion between the first crosspiece  21  and the second crosspiece  22  on the virtual line segment connecting between the center point  100  and the first point  101 , it is not possible to change the inclination angle  140  on the virtual line segment. Also, in the case where the fan grille  20  is configured as in Embodiment 6, if there is no connection portion between the first crosspiece  21  and the second crosspiece  22  on the virtual line segment connecting between the center point  100  and the fourth point  104 , it is not possible to change the inclination angle  140  on the virtual line segment. 
     Therefore, in the case where the fan grille  20  is configured as in Embodiment 6, it is not possible to define the area P 1  in the manner illustrated in  FIG. 10 . Accordingly, in the case where the fan grille  20  is configured as in Embodiment 6, the area P 1  may be defined in a stepped shape in accordance with the positions of the second crosspieces  22  as illustrated in  FIG. 23 . The area P 1  defined in a stepped shape has only to include the area P 1  illustrated in  FIG. 10 . 
     Likewise, in the case where the fan grille  20  is configured as in Embodiment 6, if there is no connection portion between the first crosspiece  21  and the second crosspiece  22  on the virtual line segment connecting between the center point  100  and the third point  103 , it is not possible to change the inclination angle  140  on the virtual line segment. Also, in the case where the fan grille  20  is configured as in Embodiment 6, if there is no connection portion between the first crosspiece  21  and the second crosspiece  22  on the virtual line segment connecting between the center point  100  and the fifth point  105 , it is not possible to change the inclination angle  140  on the virtual line segment. Therefore, in the case where the fan grille  20  is configured as in Embodiment 6, it is not possible to define the area Q 1  in the manner illustrated in  FIG. 10 . Accordingly, in the case where the fan grille  20  is configured as in Embodiment 6, the area Q 1  may be defined in a stepped shape in accordance with the positions of the second crosspieces  22  as illustrated in  FIG. 23 . The area Q 1  defined in a stepped shape has only to include the area Q 1  illustrated in  FIG. 10 . 
     Note that in the case where each second crosspiece  22  has an elongated shape in the cross-section perpendicular to the longitudinal direction, each second crosspiece  22  of Embodiment 6 is preferably configured such that the inclination angle  140  does not vary with the position on the second crosspiece  22 , in view of the easiness of manufacturing the fan grille  20 . 
     Embodiment 7 
     A refrigeration cycle apparatus includes an air-sending device, and a heat exchanger configured to exchange heat between the refrigerant flowing inside and the air supplied by the air-sending device. The air-sending device  40  of any of Embodiments 1 to 6 may be used as an air-sending device for such a refrigeration cycle apparatus other than an air-conditioning apparatus, for example. The following describes an example in which the air-sending device  40  of any of Embodiments 1 to 6 is used in an air-conditioning apparatus as an example of a refrigeration cycle apparatus. More specifically, in the following example in which the air-sending device  40  is used in a refrigeration cycle apparatus, the air-sending device  40  is used as an air-sending device for an outdoor unit of an air-conditioning apparatus. It should be noted that, in Embodiment 7, items not specifically described are the same as those of any of Embodiments 1 to 6, and the same functions and configurations as those of any of Embodiments 1 to 6 are denoted by the same reference signs. 
       FIG. 24  is a perspective view of an outdoor unit of an air-conditioning apparatus according to Embodiment 7 of the present disclosure, as viewed from an air outlet.  FIG. 25  illustrates the internal configuration of the outdoor unit of the air-conditioning apparatus according to Embodiment 7 of the present disclosure as viewed from the above.  FIG. 26  is a perspective view illustrating the outdoor unit of the air-conditioning apparatus, with a fan grille removed, according to Embodiment 7 of the present disclosure, as viewed from the air outlet.  FIG. 27  is a perspective view illustrating the internal configuration of the outdoor unit of the air-conditioning apparatus according to Embodiment 7 of the present disclosure. Note that the straight arrows in  FIG. 25  indicate the flow of air around an outdoor unit  50 . 
     The outdoor unit  50  of the air-conditioning apparatus includes an outdoor unit main body  51  serving as a casing. The outdoor unit main body  51  includes a side surface  51   a , a side surface  51   c , a front surface  51   b , a rear surface  51   d , a top surface  51   e , and a bottom surface  51   f . The side surface  51   a  and the rear surface  51   d  have air inlets  51   h  for introducing air from the outside into the outdoor unit main body  51 . The front surface  51   b  has an air outlet  53  for blowing out air from the inside of the outdoor unit main body  51  to the outside, in a front panel  52  forming a part of the front surface  51   b.    
     The inside of the outdoor unit main body  51  is divided into an air-sending chamber  56  and a machine chamber  57  by a partition plate  51   g . The air-sending chamber  56  accommodates the propeller fan  1  and the bell mouth  10  of the air-sending device  40  of any of Embodiments 1 to 6. The propeller fan  1  of the air-sending device  40  is connected to a fan motor  61  disposed on the rear surface  51   d  side via a shaft portion  62 , and is rotated by the fan motor  61 . 
     The air outlet  11  of the bell mouth  10  of the air-sending device  40  is connected to the front panel  52  of the outdoor unit to surround the outer periphery of the air outlet  53 . Note that the bell mouth  10  may be formed integrally with the front panel  52 , or may be formed separately from the front panel  52 . The air passage near the air outlet  53  is separated from the other space inside the air-sending chamber  56  by the bell mouth  10 . 
     As described above, the air-sending device  40  includes the fan grille  20  at the position downstream of the air outlet  11  of the bell mouth  10  in the direction of airflow generated by the propeller fan  1 . In the outdoor unit  50  of Embodiment 7, the fan grille  20  is disposed on the front panel  52 . Then, the front panel  52  is configured to cover the propeller fan  1  of the air-sending device  40  and the air outlet  11  of the bell mouth  10 , and also cover the air outlet  53  formed in the front panel  52 , while allowing ventilation. This prevents objects from coming into contact with the propeller fan  1 , thereby ensuring safety. 
     The air-sending chamber  56  accommodates a heat exchanger  68 . The heat exchanger  68  has a substantially L-shape in plan view, and is disposed to face the air inlets  51   h  formed in the side surface  51   a  and the rear surface  51   d . The heat exchanger  68  is configured to exchange heat between the refrigerant flowing inside and the air supplied by the air-sending device  40 . In Embodiment 7, the heat exchanger  68  is a fin-and-tube heat exchanger. That is, the heat exchanger  68  includes a plurality of fins arranged at predetermined intervals, and a plurality of heat transfer pipes extending through the fins in the arrangement direction of the fins. Refrigerant circulating in a refrigerant circuit flows through each heat transfer pipe. 
     The machine chamber  57  accommodates a compressor  64 . The compressor  64  is connected to the heat exchanger  68  via a pipe  65  and other components. The compressor  64  and the heat exchanger  68  are connected to an indoor heat exchanger, an expansion valve, and other components (not illustrated) to form a refrigerant circuit. The machine chamber  57  accommodates a board box  66 . A control board  67  disposed in the board box  66  controls the devices such as the fan motor  61  and the compressor  64  mounted on the outdoor unit  50 . 
     The outdoor unit  50  of the air-conditioning apparatus of Embodiment 7 includes the air-sending device  40  of any of Embodiments 1 to 6 that reduces noise and energy loss as compared to the related art. Therefore, the outdoor unit  50  of the air-conditioning apparatus of Embodiment 7 achieves low noise and low energy loss. 
     The air-sending device  40  of any of Embodiments 1 to 6 may be used in a refrigeration cycle apparatus other than an air-conditioning apparatus. For example, a water heater as an example of a refrigeration cycle apparatus includes a heat exchanger disposed in an outdoor unit and configured to exchange heat between the refrigerant flowing inside and the air supplied by an air-sending device. Accordingly, the air-sending device  40  of any of Embodiments 1 to 6 may be used in the outdoor unit of the water heater. 
     REFERENCE SIGNS LIST 
       1  propeller fan  1   a  rotation axis  1   b  virtual line segment  2  boss  3  blade  4  rotation direction  5  leading edge  6  trailing edge  7  outer peripheral edge  8  airflow  10  bell mouth  11  air outlet  12  edge  13  constant portion  14  varying portion  15  side wall  20  fan grille  21  first crosspiece  21   a  crosspiece portion  22  second crosspiece  23  upstream side end portion  24  downstream side end portion  40  air-sending device  50  outdoor unit  51  outdoor unit main body  51   a  side surface  51   b  front surface  51   c  side surface  51   d  rear surface  51   e  top surface  51   f  bottom surface  51   g  partition plate  51   h  air inlet  52  front panel  53  air outlet  56  air-sending chamber  57  machine chamber  61  fan motor  62  shaft portion  64  compressor  65  pipe  66  board box  67  control board  68  heat exchanger  90  airflow  91  airflow  92  airflow  100  center point  101  first point  102  second point  103  third point  104  fourth point  105  fifth point  106  sixth point  107  seventh point  108  eighth point  109  ninth point  110  tenth point  111  eleventh point  112  twelfth point  113  thirteenth point  114  fourteenth point  115  fifteenth point  116  sixteenth point  117  seventeenth point  118  eighteenth point  121  first virtual line segment  122  second virtual line segment  123  third virtual line segment  124  fourth virtual line segment  125  fifth virtual line segment  126  sixth virtual line segment  127  seventh virtual line segment  130  radial distance  131  first radial distance  132  second radial distance  140  inclination angle  150  virtual circle