US Patent 8409495 Rotor with inlet perimeters

A device for use in a molten metal pump helps alleviate jams between rotating rotor blades and a stationary pump base. The device includes inlet perimeters that partially define one or more openings, and one or more rotor blades, wherein each rotor blade has a portion that directs molten metal into a pump chamber, and a portion that directs molten metal outwards. Each rotor blade may also include a recess that makes an opening larger to enable more molten metal to pass through the openings.