Linear pump suspension system

Abstract

A linear pump with a cylinder and piston arrangement uses the armature of an electromagnet to reciprocate the piston within the cylinder along a piston axis. The armature is suspended along the piston axis by a suspension assembly including a first set of leaf springs mounted by a first retainer at a first end of the armature and a second set of leaf springs mounted by a second retainer at a second end of the armature, wherein each spring has a radially extending alignment tab mating with a corresponding alignment pocket of the associated retainer so as to align the leaf springs in the same orientation.

1 . A linear pump comprising a cylinder and piston disposed along a piston axis and an electromagnet having a stator containing a wire coil driving an armature connected to the piston to reciprocate the piston within the cylinder along the piston axis, wherein the armature is suspended along the piston axis by a plurality of leaf springs captured in at least one retainer, wherein each leaf spring has an alignment feature mating with a corresponding alignment feature of each of the at least one retainers so as to fix the orientation of each leaf spring.  
   
   
       2 . The pump of  claim 1 , wherein the plurality of leaf springs are aligned about the piston axis in essentially the same orientation.  
   
   
       3 . The pump of  claim 2 , wherein the leaf springs are bowed out of a plane perpendicular to the piston axis and wherein the leaf springs are oriented with the bow facing the same direction.  
   
   
       4 . The pump of  claim 2 , wherein the leaf springs have a web pattern and wherein the leaf springs are oriented with their web patterns aligned.  
   
   
       5 . The pump of  claim 1 , wherein the armature is suspended at each end by the leaf springs.  
   
   
       6 . The pump of  claim 1 , wherein there are two such retainers and wherein each end of the armature is suspended by at least two of the leaf springs mounted about the piston axis by the retainers.  
   
   
       7 . The pump of  claim 1 , wherein the alignment feature of the leaf springs mate with the at least one retainer in only one axial orientation.  
   
   
       8 . The pump of  claim 1 , wherein the alignment feature of the leaf springs is a radially projecting tab and the alignment feature of the at least one retainer is a pocket.  
   
   
       9 . The pump of  claim 8 , wherein there are a plurality of angularly spaced alignment tabs on each of the leaf springs and a plurality of correspondingly angularly spaced pockets in the at least one retainer.  
   
   
       10 . The pump of  claim 8 , wherein the leaf spring tab is asymmetric such that the alignment tab fits into the pocket of the retainer in only one axial orientation.  
   
   
       11 . A linear pump comprising a cylinder and piston disposed along a piston axis and an electromagnet having a stator containing a wire coil driving an armature connected to the piston to reciprocate the piston within the cylinder along the piston axis, wherein the armature is suspended along the piston axis by a suspension assembly including a first set of leaf springs mounted by a first retainer at a first end of the armature and a second set of leaf springs mounted by a second retainer at a second end of the armature, wherein each spring has a radially extending alignment tab mating with a corresponding alignment pocket of the associated retainer so as to align the leaf springs in the same axial and angular orientation.