Rotor with inlet perimeters

Abstract

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.

What is claimed is: 
     
         1 . A rotor device for use in a molten metal pump, the device comprising:
 (a) inlet means for permitting molten metal to enter a pump chamber and help prevent the jamming of a moving rotor blade against a stationary pump base;   (b) displacement means for directing molten metal into the pump chamber and then directing it outwards.   
     
     
         2 . The rotor device of  claim 1  wherein the displacement means is a plurality of rotor blades wherein each of the rotor blades has a leading face that includes a first portion that directs molten metal downward and a second portion beneath the second portion that directs molten metal outwards. 
     
     
         3 . The rotor device of  claim 2  wherein the inlet means are openings between the rotor blades. 
     
     
         4 . The rotor device of  claim 1  that further includes recess means on the displacement means, the recess means for increasing the size of the openings in order to permit more molten metal to pass through the openings. 
     
     
         5 . The rotor device of  claim 1  that further includes a bearing surface. 
     
     
         6 . The device of  claim 5  wherein the bearing surface is a ring comprised of ceramic. 
     
     
         7 . The rotor device of  claim 1  that has a plurality of rotor blades and wherein the recess means is a trailing face on each rotor blade that includes a recess that increases the size of one of the openings to help permit molten metal to pass therethrough and into a pump chamber 
     
     
         8 . The device of  claim 2  wherein the one or more rotor blades are comprised of graphite. 
     
     
         9 . The device of  claim 1  that is comprised of graphite. 
     
     
         10 . The device of  claim 1  that has a top surface comprised of ceramic. 
     
     
         11 . The device of  claim 3  wherein there are three openings. 
     
     
         12 . The device of  claim 11  wherein there are three rotor blades. 
     
     
         13 . The device of  claim 1  that further includes a threaded connective portion at the top for connecting to a rotor shaft. 
     
     
         14 . The device of  claim 1  wherein the device includes a flow-blocking plate at the bottom. 
     
     
         15 . The device of  claim 1  that further includes a flow blocking plate at the bottom and a bearing ring on the flow blocking plate. 
     
     
         16 . The device of  claim 2  wherein the first portion of each rotor blade has a horizontally-extending projection with a top surface and a bottom surface, wherein the bottom surface is angled to move molten metal into the pump chamber. 
     
     
         17 . The device of  claim 2  wherein the second portion of each rotor blade is vertical. 
     
     
         18 . The device of  claim 17  wherein the bottom surface of each horizontally-extending projection is formed at a 10°-60° downward angle relative a horizontal axis. 
     
     
         19 . The device of  claim 7  wherein each recess begins at a position forward of the second portion of the rotor blade.