Molten metal pump with vaned impeller

摘要

A molten metal pump having an elongated shaft with an impeller disposed adjacent the end of the shaft and a means for rotating the shaft. The impeller is formed with an imperforate substantially circular base surrounded by a bearing and has a surface facing toward the shaft. At least two imperforate vanes are connected to and extend substantially perpendicular from the surface and radially from the shaft or a hub securing the shaft toward a peripheral portion of the base. The vanes are spaced apart at terminal inlet ends along their entire radial dimension to create an inlet area comprised of the axial opening between adjacent vanes at the terminal ends and an outlet area comprised of a radial opening between adjacent vanes along the axial direction of the vanes. Each vane has a leading edge with a distal portion adjacent the periphery of the base portion which forms an angle of less than about 100 DEG relative to a tangent to said circular base drawn at the center of the vane.