Stacked piezoelectric diaphragm members

Abstract

A diaphragm assembly ( 20 ) comprises at least two piezoelectric diaphragm members ( 22 ) arranged in a stacking direction ( 23 ). An interface layer ( 24 ) is situated between adjacent piezoelectric diaphragm members ( 22 ). The interface layer ( 24 ) in the stacking direction ( 23 ) is displaceable but incompressible. The interface layer ( 24 ) permits lateral movement of the adjacent piezoelectric diaphragm members ( 22 ) relative to the interface layer ( 24 ) in a direction perpendicular to the stacking direction ( 23 ). The interface layer ( 24 ) can comprise, for example, an incompressible liquid or a semi-liquid. A gasket ( 26 ) can be used to seal the incompressible substance in the interface layer if necessary.

1 . A diaphragm assembly comprising: 
 at least two piezoelectric diaphragm members arranged in a stacking direction;    an interface layer situated between adjacent piezoelectric diaphragm members, the interface layer in the stacking direction being displaceable but incompressible.    
   
   
       2 . The apparatus of  claim 1 , wherein the interface layer comprises an incompressible liquid.  
   
   
       3 . The apparatus of  claim 2 , wherein a gasket entraps the interface layer between the adjacent piezoelectric diaphragm members.  
   
   
       4 . The apparatus of  claim 1 , wherein the interface layer is a semi-liquid.  
   
   
       5 . The apparatus of  claim 4 , wherein a gasket entraps the interface layer between the adjacent piezoelectric diaphragm members.  
   
   
       6 . The apparatus of  claim 1 , wherein each piezoelectric diaphragm member comprises: 
 a piezoelectric core;    a metal substrate laminated on a first side of the piezoelectric core; and    an outer metal laminated on a second side of the piezoelectric core.    
   
   
       7 . The apparatus of  claim 1 , wherein the interface layer permits lateral movement of the adjacent piezoelectric diaphragm members relative to the interface layer in a direction perpendicular to the stacking direction.  
   
   
       8 . A pump comprising: 
 a pump body for at least partially defining a pumping chamber, an inlet port, and an outlet port;    a diaphragm assembly situated in the pump body, the diaphragm assembly comprising: 
 at least two piezoelectric diaphragm members arranged in a stacking direction;  
 an interface layer situated between adjacent piezoelectric diaphragm members, the interface layer in the stacking direction being displaceable but incompressible.  
   
   
   
       9 . The apparatus of  claim 8 , wherein the interface layer comprises an incompressible liquid.  
   
   
       10 . The apparatus of  claim 9 , wherein a gasket entraps the interface layer between the adjacent piezoelectric diaphragm members.  
   
   
       11 . The apparatus of  claim 8 , wherein the interface layer comprises a semi- liquid.  
   
   
       12 . The apparatus of  claim 11 , wherein a gasket entraps the interface layer between the adjacent piezoelectric diaphragm members.  
   
   
       13 . The apparatus of  claim 8 , wherein each piezoelectric diaphragm member comprises: 
 a piezoelectric core;    a metal substrate laminated on a first side of the piezoelectric core; and    an outer metal laminated on a second side of the piezoelectric core.    
   
   
       14 . The apparatus of  claim 8 , wherein the interface layer permits lateral movement of the adjacent piezoelectric diaphragm members relative to the interface layer in a direction perpendicular to the stacking direction.