Servo driven pump

Abstract

A double diaphragm pump having opposing diaphragms acted upon by a thrust rod are driven by a linear actuator preferably connected to a motor, such as a servo motor. The linear actuator is restricted to linear only motion and may have a piston oppositely oriented relative to a direction of a shaft extending from the motor.

Having set forth the nature of the invention, what is claimed herein is: 
     
         1 . A double diaphragm pump characterized by opposing first and second fluid chambers which selectively receive input from an inlet and discharge output from an outlet, with the fluid chambers respectively acted upon by respective diaphragms in an alternating manner whereby when the first chamber is filling with input, the second chamber is discharging output, and when the first chamber is discharging output, the second chamber is filling with input, the improvement comprising:
 a linear actuator connected to a thrust tube, whereby the thrust tube is connected to the diaphragms of the first and second fluid chambers and the linear actuator is restricted to linear motion along an axis thereby driving the thrust tube in reciprocating linear motion.   
     
     
         2 . The pump of  claim 1  further comprising a motor having a rotating shaft operably coupled to the linear actuator instigating the reciprocating linear motion of the linear actuator. 
     
     
         3 . The pump of  claim 2  further comprising a gear box intermediate the motor and the linear actuator. 
     
     
         4 . The pump of  claim 3  whereby the gear box increases torque from the motor as applied to the linear actuator. 
     
     
         5 . The pump of  claim 4  wherein the motor is a servo motor. 
     
     
         6 . The pump of  claim 3  wherein a drive shaft of the motor extends in a direction oppositely oriented relative to a piston extending from the linear actuator. 
     
     
         7 . The pump of  claim 1  wherein the linear actuator has threads which selectively drive a piston linearly along the axis. 
     
     
         8 . The pump of  claim 7  wherein the piston is connected to the thrust tube. 
     
     
         9 . The pump of  claim 7  wherein the threads are a portion of a precision lead screw. 
     
     
         10 . The pump of  claim 9  wherein the precision lead screw has a rotation axis and the rotation axis is parallel to a reciprocation axis of the thrust tube. 
     
     
         11 . The pump of  claim 1  driven by a controller. 
     
     
         12 . The pump of  claim 11  wherein the controller is one of a programmable logic controller (PLC) and a human machine interface (HMI). 
     
     
         13 . The pump of  claim 11  wherein the controller directs at least one of stroke, speed and cycles. 
     
     
         14 . The pump of  claim 11  wherein the controller permits adjustment of at least one of stroke, speed and cycles by an operator. 
     
     
         15 . The pump of  claim 11  wherein the controller provides feedback to an electric data acquisition system. 
     
     
         16 . The pump of  claim 1  wherein the axis is parallel to a reciprocation axis of the thrust tube. 
     
     
         17 . The pump of  claim 16  wherein the axis is colinear with the reciprocation axis.