Patent ID: 8317478
Filing Date: 2012-11-27
Classification: F04D

Abstract:
1. An impeller comprising: a support portion centered on a central axis; a plurality of blades extending radially outward from an outside surface of the support portion, and arranged to rotate about the central axis together with the support portion to produce an airflow; and a substantially annular joining member extending in a circumferential direction along an arbitrary circle centered on the central axis, and arranged to join the blades to one another; wherein in each of the blades, a point of intersection of a leading edge of the blade with a blade end of the blade is positioned forward, with respect to a rotation direction, relative to a point of intersection of the leading edge with the outside surface of the support portion, the leading edge being an edge of the blade positioned most forward with respect to the rotation direction, the blade end being a radially outer end of the blade; the joining member is positioned radially inward of the blade end of each of the blades; the support portion, the blades, and the joining member are defined together as a single continuous monolithic member of molded resin or plastic; the joining member includes two surfaces facing in opposite directions along the central axis, and at least one of the two surfaces has provided thereon at least one increased width portion defined by an increase in a radial width of the surface; and the at least one increased width portion is a solid member that is provided in an overlapping section where the surface of the joining member on which the increased width portion is provided overlaps with one of the blades when viewed in a direction along the central axis.