Glass impeller for a blood pump

Abstract

A blood pump includes an impeller assembly housing; and an impeller assembly disposed within the impeller assembly housing. The impeller assembly includes an impeller having a main body, at least one impeller blade extending outwardly therefrom, and a skirt disposed around at least a portion of the main body. At least a portion of the at least one impeller blade is disposed between the main body and an inner surface of the skirt.

We claim: 
     
         1 . A method of manufacturing a glass impeller for a blood pump, the method comprising:
 providing a block of a glass;   modifying the glass by laser radiation; and   selectively removing a portion of the modified glass by wet chemical etching to form the glass impeller.   
     
     
         2 . The method of  claim 1 , wherein the glass is a chemically strengthened glass. 
     
     
         3 . The method of  claim 1 , wherein the glass comprises a surface enriched with potassium ions. 
     
     
         4 . The method of  claim 1 , wherein the glass comprises a surface in a state of compression and a core in a state of tension. 
     
     
         5 . The method of  claim 1 , wherein the glass impeller has a selectivity greater than 500:1. 
     
     
         6 . The method of  claim 1 , wherein the glass impeller has a root mean square surface roughness of less than 5 nm with a 1×1 mm 2  measuring field. 
     
     
         7 . The method of  claim 1 , wherein the glass impeller has a root mean square micro roughness of less than 0.4 nm with a 50×70 μ 2  measuring field. 
     
     
         8 . A method of manufacturing a blood pump, the method comprising:
 providing a block of a glass;   modifying the glass by laser radiation;   selectively removing a portion of the modified glass by wet chemical etching to form a glass impeller; and   coupling the glass impeller to a drive shaft within a housing of the blood pump.   
     
     
         9 . The method of  claim 8 , wherein the glass is a chemically strengthened glass. 
     
     
         10 . The method of  claim 8 , wherein the glass comprises a surface enriched with potassium ions. 
     
     
         11 . The method of  claim 8 , wherein the glass comprises a surface in a state of compression and a core in a state of tension. 
     
     
         12 . The method of  claim 8 , wherein the glass impeller has a selectivity greater than 500:1. 
     
     
         13 . The method of  claim 8 , wherein the glass impeller has a root mean square surface roughness of less than 5 nm with a 1×1 mm 2  measuring field. 
     
     
         14 . The method of  claim 8 , wherein the glass impeller has a root mean square micro roughness of less than 0.4 nm with a 50×70 μ 2  measuring field.