Touch down of blood pump impellers

Abstract

A blood pump having rotor and/or stator touch down zones to prevent pump failure or hernolysis which can occur if the rotor comes into contact with the stator due to power failure or mechanical shock. The touch down zones can include forming, or coating, portions of adjacent surfaces of the stator and rotor which can come into contact if a rotor touch down occurs. The materials used to form or coat the touch down zones can have properties which ensure that no consequential damage to the contacting surfaces occurs.

1 . A blood pump having inlet and outlet regions, said blood pump comprising: 
 a. a stator having at least one of first and second contact portions adjacent at least one of said inlet and outlet regions, respectively;    b. a rotor magnetically supported adjacent said stator for rotation relative thereto, said rotor having at least one of third and fourth contact portions adjacent said at least one of first and second contact portions, respectively;    c. each of said first and second contact portions having properties resistant to damage resulting from potential touch down of said rotor against said stator; and    d. each of said third and fourth contact portions having properties resistant to damage resulting from potential touch down of said rotor against said stator.    
     
     
         2 . The blood pump of  claim 1  further comprising: 
 a. at least one of said first and second contact portions being a relatively hard material;  
 b. at least one of said third and fourth contact portions being a relatively soft material;  
 c. wherein at least one of said first and third and said second and fourth contact portions are soft and hard materials, respectively, such that a soft contact portion is adjacent a hard contact portion.  
 
     
     
         3 . The blood pump of  claim 2  further comprising: 
 a. said relatively hard materials are at least one of titanium, alloyed titanium, and a jewel; and  
 b. said relatively soft materials are at least one of polymer, rubber, and a combination thereof.  
 
     
     
         4 . The blood pump of  claim 1  wherein each of said first through fourth contact portions are relatively hard materials.  
     
     
         5 . The blood pump of  claim 4  wherein each of said first through fourth contact portions are at least one of titanium, alloyed titanium, and a jewel.  
     
     
         6 . The blood pump of  claim 5  wherein said first through fourth contact portions are one of titanium and alloyed titanium, and further comprising said first through fourth contact portions having one of a crystalline-diamond-like coating, titanium nitride coating, and graphitic-diamond-like coating.  
     
     
         7 . The blood pump of  claim 1  wherein each of said first through fourth contact portions are relatively soft materials.  
     
     
         8 . The blood pump of  claim 7  wherein each of said first through fourth contact portions are at least one of polymer, rubber, and a combination thereof.  
     
     
         9 . The blood pump of  claim 1  wherein at least one of said second and third contact portions comprise blade members, and said blade members being a relatively soft material.  
     
     
         10 . The blood pump of  claim 9  further comprising at least one of said first and fourth contact portions adjacent said at least one of said second and third contact portions being a relatively hard material.  
     
     
         11 . A blood pump having inlet and outlet regions, said blood pump comprising: 
 a. a stator having at least one of first and second contact portions adjacent said outlet region;    b. a rotor magnetically supported adjacent said stator for rotation relative thereto, said rotor having at least one of third and fourth contact portions adjacent said at least one of first and second contact portions, respectively;    c. each of said first and second contact portions having properties resistant to damage resulting from potential touch down of said rotor against said stator; and    d. each of said third and fourth contact portions having properties resistant to damage resulting from potential touch down of said rotor against said stator.    
     
     
         12 . The blood pump of  claim 11  further comprising: 
 a. at least one of said first and second contact portions being a relatively hard material;  
 b. at least one of said third and fourth contact portions being a relatively soft material;  
 c. wherein at least one of said first and third and said second and fourth contact portions are soft and hard materials, respectively, such that a soft contact portion is adjacent a hard contact portion.  
 
     
     
         13 . The blood pump of  claim 12  further comprising: 
 a. said relatively hard materials are at least one of titanium, alloyed titanium, and a jewel; and  
 b. said relatively soft materials are at least one of polymer, rubber, and a combination thereof.  
 
     
     
         14 . The blood pump of  claim 11  wherein each of said first through fourth contact portions are relatively hard materials.  
     
     
         15 . The blood pump of  claim 14  wherein each of said first through fourth contact portions are at least one of titanium, alloyed titanium, and a jewel.  
     
     
         16 . The blood pump of  claim 15  wherein said first through fourth contact portions are one of titanium and alloyed titanium, and further comprising said first through fourth contact portions having one of a crystalline-diamond-like coating, titanium nitride coating, and graphitic-diamond-like coating.  
     
     
         17 . The blood pump of  claim 11  wherein each of said first through fourth contact portions are relatively soft materials.  
     
     
         18 . The blood pump of  claim 17  wherein each of said first through fourth contact portions are at least one of polymer, rubber, and a combination thereof.  
     
     
         19 . The blood pump of  claim 11  wherein at least one of said third and fourth contact portions comprise blade members, and said blade members being a relatively soft material.  
     
     
         20 . The blood pump of  claim 19  further comprising at least one of said first and second contact portions being a relatively hard material.