Variable Stroke Length Electrically Operated Diaphragm Pump

Abstract

A variable stroke length EOD pump system is provided that includes a diaphragm pump and an electromagnetic linear actuator that operates the diaphragm pump. The linear actuator includes two stator halves, and an armature. The armature is supported for linear motion along an axis of and between field poles of the stator halves. Each stator half may also include a drive coil partially surrounded by a magnetically permeable core.

What is claimed: 
     
         1 . An electrically operated diaphragm pump system comprising:
 a diaphragm pump;   an electromagnetic linear actuator that operates the diaphragm pump;   wherein the linear actuator includes:
 two stator halves, and 
 an armature; 
   wherein the armature is supported for linear motion along an axis of and between field poles of the stator halves;   wherein each stator half includes a drive coil partially surrounded by a magnetically permeable core;   a drive circuit;   wherein the drive circuit includes a microcontroller, a position sensor for communicating the armature position to the microcontroller, an electronic switch associated with each stator coil for controlling current through the associated coil, the drive circuit including elements enabling the microcontroller to selectively operate the switches, the microcontroller being programmed to monitor the armature position and operated the switches at appropriate times to control the armatures motion.   
     
     
         2 . The pump system of  claim 1 , wherein the microcontroller is programmed to control an axial position of the armature as a function of time.