Miniature pressure-driven pumps

Abstract

A miniature pump including a first chamber, a second chamber, a deformable membrane provided within the second chamber that divides the second chamber into first and second sub-chambers, the second sub-chamber defining a reservoir configured to contain liquid to be dispensed, a passage that connects the first chamber to the first sub-chamber, and an outlet in fluid communication with the reservoir, wherein pressurized fluid within the first internal chamber flows through the passage and into the first sub-chamber to compress the deformable membrane and cause liquid contained within the reservoir to flow out from the reservoir through the outlet and wherein the deformable membrane does not generate significant restoring forces when it is deformed and, therefore, will not return to its initial undeformed shape unless the reservoir is refilled.

1 . A miniature pump comprising:
 a pump chamber comprising a first sub-chamber and a second sub-chamber;   a deformable membrane provided within the pump chamber, the deformable membrane dividing the pump chamber into the first sub-chamber and the second sub-chamber, the second sub-chamber defining a reservoir to contain a liquid to be dispensed, the reservoir configured to store the liquid when the reservoir is in an undeformed state with a second pressure being applied on the deformable membrane, the second pressure being equal to or greater than a first pressure of fluid in the first sub-chamber being applied on the deformable membrane in the undeformed state;   a passage attached to the first sub-chamber, the passage configured to deliver the fluid into the first sub-chamber; and   an outlet connected to the reservoir of the second sub-chamber.   
     
     
         2 . The miniature pump of  claim 1 , wherein the second sub-chamber is configured to, in a deformed state, dispense the liquid when the second pressure in the second sub-chamber being applied on the deformable membrane is less than the first pressure of the fluid in the first sub-chamber being applied on the deformable membrane. 
     
     
         3 . The miniature pump of  claim 1 , further comprising:
 an air chamber,   wherein the passage connects the air chamber to the first sub-chamber.   
     
     
         4 . The miniature pump of  claim 3 , wherein the air chamber includes the fluid, and wherein the fluid comprises pressurized air. 
     
     
         5 . The miniature pump of  claim 4 , further comprising an air inlet for supplying the pressurized air to the air chamber. 
     
     
         6 . The miniature pump of  claim 1 , further comprising a liquid inlet connected to the second sub-chamber for filling the reservoir with the liquid. 
     
     
         7 . The miniature pump of  claim 6 , further comprising a resealable septum associated with the liquid inlet for delivering the liquid to the reservoir. 
     
     
         8 . The miniature pump of  claim 7 , further comprising a compression ring for compressing the resealable septum to induce lateral stress within the resealable septum that prevents leakage. 
     
     
         9 . The miniature pump of  claim 1 , further comprising a debubbler in fluid communication with the outlet, the debubbler being configured to remove bubbles from dispensed liquid. 
     
     
         10 . The miniature pump of  claim 9 , further comprising a fluidic resistor in fluid communication with the debubbler, the fluidic resistor being configured to control a rate of flow of the dispensed liquid. 
     
     
         11 . A method for pumping via a miniature pump, comprising:
 introducing liquid into a pump chamber, the pump chamber comprising a first sub-chamber, a second sub-chamber, and a deformable membrane, the deformable membrane dividing the pump chamber into the first sub-chamber and the second sub-chamber, the second sub-chamber defining a reservoir configured to contain the liquid to be dispensed;   introducing, via a passage, fluid to the first sub-chamber;   pressurizing the fluid in the first sub-chamber to compress the deformable membrane; and   in response to the compressed deformable membrane, dispensing the liquid through an output connected to the second sub-chamber.   
     
     
         12 . The method of  claim 11 , wherein introducing the liquid to the pump chamber comprises:
 inserting the liquid into the second sub-chamber to generate a restoring force to the deformable membrane.   
     
     
         13 . The method of  claim 11 , wherein pressurizing the fluid in the first sub-chamber comprises:
 pressuring the fluid in the first sub-chamber with a first pressure in the first sub-chamber to be greater than a second pressure of the liquid in the second sub-chamber.   
     
     
         14 . The method of  claim 11 , further comprising:
 inserting the fluid into an air chamber being connected to the passage.   
     
     
         15 . The method of  claim 14 , further comprising:
 supplying, via an air inlet connected to the air chamber, the fluid to the air chamber.   
     
     
         16 . The method of  claim 11 , further comprising:
 filling, via a liquid inlet connected to the second sub-chamber, the reservoir with the liquid.   
     
     
         17 . The method of  claim 16 , further comprising:
 delivering, via a resealable septum associated with the liquid inlet, the liquid to the reservoir.   
     
     
         18 . The method of  claim 17 , further comprising:
 compressing, via a compression ring, the resealable septum to induce lateral stress within the resealable septum that prevents leakage.   
     
     
         19 . The method of  claim 11 , further comprising
 removing, via a debubbler in fluid communication with an outlet, bubbles from the dispensed liquid.   
     
     
         20 . A miniature pressure-driven pump comprising:
 a pump body comprising an internal air chamber, an internal pump chamber, and an internal passage connecting the internal air chamber to the internal pump chamber, the pump body further comprising an air inlet in fluid communication with the air chamber, a liquid inlet in fluid communication with the pump chamber, and a liquid outlet in fluid communication with the pump chamber;   a deformable membrane provided within the pump chamber that divides the pump chamber into an air sub-chamber and a liquid sub-chamber, the liquid sub-chamber defining a liquid reservoir configured to contain liquid to be dispensed, the liquid sub-chamber in an undeformed state containing the liquid with a first pressure in the liquid sub-chamber to the deformable membrane being equal to or greater than a second pressure of fluid in the air sub-chamber to the deformable membrane;   a valve provided within the air inlet through which air can pass to fill the air chamber with pressurized air;   a septum provided within the liquid inlet through which the liquid can pass to fill the liquid reservoir with the liquid;   a compression ring that compresses the septum to induce lateral stress within the septum that prevents liquid leakage;   a debubbler in fluid communication with the liquid outlet, the debubbler being configured to remove bubbles from dispensed liquid; and   a fluidic resistor in fluid communication with the debubbler, the fluidic resistor being configured to control a rate of flow of the dispensed liquid.