Linear pump cooling system

Abstract

A linear pump has a housing containing a cylinder and piston arrangement and a motor with a slotted stator containing a wire coil driving an armature connected to the piston to reciprocate the piston within the cylinder along a piston axis. The housing defines a pair of straight air intake vent tubes in communication with ambient air and extending to proximate the motor. The vent tubes serve to provide both the primary breathing passages of the pump as well as cooling passages for the motor.

1 - 10 . (canceled)  
   
   
       11 . A pump comprising a housing containing a motor and having an air intake opening and a vent tube extending from the intake opening to proximate the motor.  
   
   
       12 . The pump of  claim 11 , wherein the vent tube directs the intake air at the motor essentially perpendicular to the axis.  
   
   
       13 . The pump of  claim 12 , wherein the motor includes an armature coupled to a pumping member disposed in a pump chamber and a stator containing a wire coil disposed about the armature, the stator having an opening to allow intake air to pass by the wire coil.  
   
   
       14 . The pump of  claim 13 , wherein the pump chamber is a cylinder and the pumping member is a piston adapted for reciprocation within the cylinder.  
   
   
       15 . The pump of  claim 13 , wherein the stator includes a plurality of axial slots spaced apart about the axis allowing intake air exiting the vent tube to pass directly through the motor.  
   
   
       16 . The pump of  claim 11 , wherein the vent tube is defined by the housing.  
   
   
       17 . The pump of  claim 11 , wherein the pump housing has a plurality of air intake openings and wherein there are a plurality of vent tubes.  
   
   
       18 . The pump of  claim 11 , wherein the vent tube is rigid and straight.  
   
   
       19 . A linear pump comprising a housing containing a cylinder and a piston disposed along a piston axis and a motor having a slotted 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 housing defines an air intake vent tube in communication with ambient air and extending to proximate the motor.  
   
   
       20 . The pump of  claim 19 , wherein the stator includes a plurality of axial slots spaced apart about the piston axis allowing intake air exiting the vent tube to pass directly through the motor.  
   
   
       21 . The pump of  claim 19 , wherein the housing defines two such vent tubes arranged in parallel.