Pump actuator and method for pump operation

Abstract

Method and apparatus for controlling a moveable pumping diaphragm and a liquid color diaphragm pump, including a housing, a movable pin slidably residing within the housing, a potentiometer connected to and residing within the housing for sensing movement of the pin, riding against the diaphragm of the pump and a spring for biasing the pin against the diaphragm.

1 ) A method for operating a pump having a movable pumping member and a pumping chamber, comprising:
 a) positioning a movable reciprocable member in contact with the pumping member to move reciprocally in concert with the pumping member;   b) sensing position of the reciprocable member and producing signals indicative thereof;   c) periodically applying force to the pumping member to move the pumping member and thereby effectuate pumping of fluid from the chamber;   d) using the signals to regulate frequency of force application to the pumping member to achieve a preselected rate of output from the pump.   
     
     
         2 ) The method of  claim 1  further comprising:
 a) recording the signals at the extremities of reciprocable member travel; 
 b) using those signals and known length of reciprocable member travel to determine location of the reciproable member based on signal received at a given time; 
 c) adjusting the frequency of application of force to the pumping member according to the location of the reciprocable member to maintain a desired output from the pump. 
 
     
     
         3 ) The method of  claim 2  wherein the step of using those signals and known length of reciprocable member travel to determine location of the reciproable member based on signal received at a given time further includes determining the relationship between duration of force application to the pumping member and pumping member displacement. 
     
     
         4 ) The method of  claim 1  wherein the pumping member is a diaphragm. 
     
     
         5 ) The method of  claim 1  wherein the sensing is performed by a potentiometer. 
     
     
         6 ) The method of  claim 1  wherein the force is pneumatically applied. 
     
     
         7 ) The method of  claim 1  wherein the pumping chamber is air-tight. 
     
     
         8 ) The method of  claim 5  wherein the potentiometer is within an actuator chamber. 
     
     
         9 ) The method of  claim 8  wherein the actuator chamber is sealed. 
     
     
         10 ) The method of  claim 9  wherein the actuator chamber is within polymer foam. 
     
     
         11 ) The method of  claim 1  further comprising adjusting the frequency of application of force to the pumping member according to the location of the reciprocable member to maintain a desired output from the pump. 
     
     
         12 ) The method of  claim 2  wherein the force is applied to the pumping member by bursts of air. 
     
     
         13 ) The method of  claim 1  further comprising the steps of:
 a) noting position of the reciprocable member as indicated by a potentiometer signal; 
 b) applying a burst of air to the pumping member; 
 c) recording a second potentiometer signal indicative of reciprocable member position; and 
 d) determining pumping member movement as a function of applied force duration from the movement of the reciprocable member in response to the air burst applied to the pumping member. 
 
     
     
         14 ) The method of  claim 1  wherein periodically applying force to the pumping member to move the pumping member and thereby effectuate pumping of fluid from the chamber is performed by controlling duration and timing of air bursts applied to the pumping member. 
     
     
         15 ) A method for operating a liquid color diaphragm pump, comprising controlling duration and sequencing of bursts of air applied to a diaphragm contacting the liquid color being pumped. 
     
     
         16 ) A method for operating a liquid color pump having a movable pumping member and a sealed pumping chamber, comprising:
 a) positioning a movable reciprocable member within an actuator chamber in contact with the pumping member to move reciprocally in concert with the pumping member;   b) sensing position of the reciprocable member within the actuator chamber and producing signals indicative thereof;   c) periodically pneumatic applying force to the movable pumping member to move the pumping member and thereby effectuate pumping of liquid color;   d) using the signals to regulate frequency of pneumatic force application to the pumping member to achieve a desired rate of output from the pump.   
     
     
         17 ) An actuator for controlling a movable pumping member in a pump, comprising:
 a) a housing;   b) a movable pin slidably residing within the housing, having an extremity portion passing through the housing for contacting the movable pumping member and moving unitarily therewith;   c) a potentiometer connected to and residing within the housing for sensing movement of the pin and producing a signal indicative thereof; and   d) a spring for biasing the pin against the pumping member.   
     
     
         18 ) Apparatus of  claim 17  wherein the housing has a first aperture for connection to a supply of pulsed air, wherein the housing has a sealed chamber within the pin, spring and potentiometer reside. 
     
     
         19 ) Apparatus of  claim 17  wherein the potentiometer has a movable portion positioned between and contacting the spring and the pin, for movement with the pin. 
     
     
         20 ) Apparatus of  claim 18  wherein a portion of the housing comprising the chamber is polymer foam. 
     
     
         21 ) Apparatus of  claim 17  wherein the signals are electrical signals, the potentiometer has terminals providing the electrical signals indicative of movement of the pin, and the apparatus further comprises:
 a) signal carriers electrically connected to the terminals and passing through housing; and 
 b) electrical connectors mounted on the housing exterior and being electrically connected to the signal carriers. 
 
     
     
         22 ) Apparatus of  claim 20  wherein the signals are electrical signals, the potentiometer has terminals providing the electrical signals indicative of movement of the pin, and the apparatus further comprises:
 a) signal carriers electrically connected to the terminals and passing through the polymer foam; and 
 b) electrical connectors mounted on the chamber exterior and being electrically connected to the signal carriers. 
 
     
     
         23 ) Apparatus of  claim 17  wherein the pumping member is a diaphragm. 
     
     
         24 ) An actuator for controlling a movable pumping diaphragm in a liquid color diaphragm pump, comprising:
 a) a housing;   b) a movable pin slidably residing within the housing, having an extremity portion passing through the housing for contacting the movable pumping member and moving unitarily therewith;   c) a potentiometer connected to and residing within the housing for sensing movement of the pin and producing a signal indicative thereof; and   d) a spring for biasing the pin against the pumping member;   
       wherein the housing comprises a sealed chamber within which the pin, spring and potentiometer reside; the potentiometer comprises a movable portion positioned between and contacting the spring and the pin for movement with the pin; a portion of the housing comprising the chamber is polymer foam; the potentiometer has terminals providing the signals indicative of pin movement; and further comprising
 e) signal carriers electrically connected to the terminals and passing through the polymer foam.