Dosing pump system

Abstract

A compact, modular dosing pump system that is capable of microdose and macrodose volume flow rates, reduces or eliminates the need for additional flow control components such as temperature and pressure sensors, and utilizes a wider operational flow range than existing systems while maintaining the level of accuracy and precision exhibited by conventional dosing pump systems is provided. The dosing pump utilizes a control system to deliver a range of fluid volumes. The control system monitors the motor emf voltage, calculates the flow rate, and makes adjustments to the pump motor voltage to precisely maintain the desired flowrate.

What is claimed is: 
     
         1 . A pump system comprising:
 A controller and a fluid pump including a motor, said controller being operably connected to said fluid pump;   wherein the controller monitors a motor electromotive force and controls the operation of said motor by utilizing information pertaining to the motor electromotive force to adjust the pulse width of a voltage applied to the motor.   
     
     
         2 . The pump system of  claim 1  wherein said fluid pump further comprises one or more valves and wherein the valves are only opened upon an application of sufficient pressure by fluid to the valves and only closed when there is an application of insufficient pressure by fluid to force fluid through the valves. 
     
     
         3 . The pump system of  claim 1  wherein the controller generates a signal based on the motor electromotive force indicating that a fluid supply for the pump is depleted. 
     
     
         4 . The pump system of  claim 1  wherein the controller includes a predefined set of flow rate values such that at least one of said predefined flow rate values corresponds to a fluid to be pumped; and wherein the controller, in response to an input provided to the controller corresponding to a fluid to be pumped, utilizes at least one of said flow rate values to control a flow rate of fluid flowing out of the fluid pump by controlling the operation of the motor. 
     
     
         5 . The pump system of  claim 1  wherein the controller includes one or more predefined flow rate values, one or more predefined motor electromotive force values, and one or more predefined fluid property values; and wherein the controller adjusts the pulse width of the voltage to be applied to the motor by using at least one predefined flow rate value, at least one predefined motor electromotive force value, and at least one fluid property value. 
     
     
         6 . The pump system of  claim 1  wherein the controller controls the operation of the motor without utilizing an input from a sensor that senses an actual fluid flow rate. 
     
     
         7 . The pump system of  claim 1  wherein the controller includes a predefined value corresponding to a desired motor electromotive force and wherein said controller modulates the voltage applied to the motor based on a sensed motor electromotive force in order to reduce a divergence between the sensed motor electromotive force and the predefined value corresponding to the desired motor electromotive force. 
     
     
         8 . The pump system of  claim 1  wherein a flow rate of fluid exiting the fluid pump is calculated by the controller based on information pertaining the motor electromotive force. 
     
     
         9 . A pump system as in  claim 1  wherein said fluid pump further comprises a pump input and a pump output in fluid communication with a fluid flow circuit, said flow circuit comprising a circuit fluid inlet, a bypass loop, an outlet branch and a circuit fluid outlet, wherein
 said bypass loop includes, an input flow channel in fluid communication with said circuit fluid inlet and said pump input, a bypass loop valve, an output flow channel in fluid communication with said pump output and said bypass loop valve, and a fluid return channel in fluid communication with said bypass loop valve and said input flow channel; 
 said outlet branch includes, an outlet branch valve, an outlet branch flow channel in fluid communication with said output flow channel of said bypass loop and said outlet branch valve, and a fluid exhaust channel in fluid communication with said outlet branch valve and said circuit fluid outlet; and 
 wherein at least one of said bypass loop valve and said outlet branch valve includes an orifice size selector, wherein said orifice size selector comprises a first orifice having a discrete size and a second orifice having a discrete size that is different than the discrete size of the first orifice. 
 
     
     
         10 . The pump system of  claim 9  wherein at least one of said bypass loop valve and said outlet branch valve is a check valve. 
     
     
         11 . The pump system of  claim 10  wherein the cracking pressure of said bypass loop valve is greater than the cracking pressure of said outlet branch valve. 
     
     
         12 . The pump system of  claim 9  wherein said orifice size selector comprises two or more orifices each having a discrete size such that said orifices may be moved into alignment with at least one of said bypass loop valve and said outlet branch valve so as to provide a fluid pathway through the orifice size selector and into at least one of said bypass loop valve and said outlet branch valve. 
     
     
         13 . The pump system of  claim 12  wherein the controller is further operatively connected to said orifice size selector and operates the orifice size selector so as to move an orifice of the orifice size selector into alignment with a fluid path in response to an input. 
     
     
         14 . The pump system of  claim 13  wherein the controller further includes a predefined flowrate value and a predefined fluid property value and wherein said controller selects at least one of the orifices of the orifice size selector based at least in part on said predefined flowrate value and said predefined fluid property value. 
     
     
         15 . The pump system of  claim 12  wherein the only moving structures in the pump system are the pump motor, the valves, and the orifice size selector. 
     
     
         16 . The pump system of  claim 14  wherein the controller only controls the operation of the pump motor and the operation of the orifice size selector. 
     
     
         17 . The pump system of  claim 1  further comprising a computer wherein the controller transmits information regarding the operation of the pump system to the computer. 
     
     
         18 . A pump system comprising:
 a fluid pump having an pump input and a pump output in fluid communication with a fluid flow circuit wherein said flow circuit comprises a circuit fluid inlet, a bypass loop, an outlet branch and a circuit fluid outlet, wherein   said bypass loop includes, an input flow channel in fluid communication with said circuit fluid inlet and said pump input, a bypass loop valve, an output flow channel in fluid communication with said pump output and said bypass loop valve, and a fluid return channel in fluid communication with said bypass loop valve and said input flow channel;   said outlet branch includes, an outlet branch valve, an outlet branch flow channel in fluid communication with said output flow channel of said bypass loop and said outlet branch valve, a secondary exhaust orifice, said outlet branch valve being in fluid communication with said secondary exhaust orifice, and a fluid exhaust channel in fluid communication with said secondary exhaust orifice such and said circuit fluid outlet; and   wherein at least one of said bypass loop valve and said outlet branch valve includes an orifice size selector, wherein said orifice size selector comprises a first orifice having a discrete size and a second orifice having a discrete size that is different than the discrete size of the first orifice.   
     
     
         19 . A pump system comprising:
 (a) a first fluid pump having an pump input and a pump output in fluid communication with a fluid flow circuit wherein said flow circuit comprises a circuit fluid inlet, a bypass loop, an outlet branch and a circuit fluid outlet, wherein
 said bypass loop includes, a input flow channel in fluid communication with said circuit fluid inlet and said pump input, a bypass loop valve, an output flow channel in fluid communication with said pump output and said bypass loop valve, and a fluid return channel in fluid communication with said bypass loop valve and said input flow channel; 
 said outlet branch includes, an outlet branch valve, an outlet branch flow channel in fluid communication with said output flow channel of said bypass loop and said outlet branch valve, and a fluid exhaust channel in fluid communication with said outlet branch valve and said circuit fluid outlet; and 
 wherein at least one of said bypass loop valve and said outlet branch valve includes an orifice size selector, wherein said orifice size selector comprises a first orifice having a discrete size and a second orifice having a discrete size that is different than the discrete size of the first orifice; 
   (b) a second fluid pump having an pump input and a pump output in fluid communication with a fluid flow circuit wherein said flow circuit comprises a circuit fluid inlet, a bypass loop, an outlet branch and a circuit fluid outlet, wherein
 said bypass loop includes, a input flow channel in fluid communication with said circuit fluid inlet and said pump input, a bypass loop valve, an output flow channel in fluid communication with said pump output and said bypass loop valve, and a fluid return channel in fluid communication with said bypass loop valve and said input flow channel; 
 said outlet branch includes, an outlet branch valve, an outlet branch flow channel in fluid communication with said output flow channel of said bypass loop and said outlet branch valve, and a fluid exhaust channel in fluid communication with said outlet branch valve and said circuit fluid outlet; and 
 wherein at least one of said bypass loop valve and said outlet branch valve includes an orifice size selector, wherein said orifice size selector comprises a first orifice having a discrete size and a second orifice having a discrete size that is different than the discrete size of the first orifice; and 
   (c) one or more controllers wherein a first predefined reference value is stored in at least one controller and a second predefined reference value is stored in at least one controller; wherein the first predefined reference value is based on at least one physical property of the first fluid pump; and wherein the second predefined reference value is based on at least one physical property of the second fluid pump.