Micropump and driving method thereof

Abstract

Provided are a micropump that makes it possible to reduce the entire size and improve pumping performance of fluid, and a method of operating the micropump. The micropump includes a case that forms a first space and a second space that are connected through a connection channel, a fluid intake pipe that is connected to the first space, a fluid discharge pipe that is connected to the second space, a first deforming member that is disposed on the case to cover the first space, and a second deforming member that is disposed on the case to cover the second space. The second deforming member is formed larger than the first deforming member and the maximum displacement of the second deforming member is larger than the maximum displacement of the first deforming member.

What is claimed is: 
     
         1 . A micropump comprising:
 a case that forms a first space and a second space that are connected through a connection channel;   a fluid intake pipe that is positioned at a side of the case and connected with the first space;   a fluid discharge pipe that is positioned at the other side of the case and connected with the second space;   a first deforming member that is disposed on the case to cover the first space and deformed by an electric signal; and   a second deforming member that is disposed on the case to cover the second space and deformed by an electric signal,   wherein the second deforming member is formed larger than the first deforming member, and   the maximum displacement of the second deforming member is larger than the maximum displacement of the first deforming member.   
     
     
         2 . The micrcopump of  claim 1 , wherein:
 the first deforming member and the second deforming member are implemented by piezoelectric actuators.   
     
     
         3 . The micropump of  claim 2 , wherein:
 the first deforming plate includes a first conductive elastic plate and a first piezoelectric device, and   the second deforming member includes a second conductive elastic plate and a second piezoelectric device.   
     
     
         4 . The micropump of  claim 3 , further comprising:
 a plurality of lead wires that is connected to the first conductive elastic plate, the first piezoelectric device, the second conductive elastic plate, and the second piezoelectric device, respectively; and   a controller that is electrically connected with the plurality of lead wires.   
     
     
         5 . The micropump of  claim 1 , wherein:
 the first deforming member and the second deforming member are made of artificial muscles.   
     
     
         6 . The micropump of  claim 5 , wherein:
 the first deforming member includes a first imitative muscle and a first electrode, and   the second deforming member includes a second imitative muscle and a second electrode.   
     
     
         7 . The micropump of  claim 6 , wherein:
 the first imitative muscle and the second imitative muscle include nanofiber made of electric active hydrogel.   
     
     
         8 . The micropump of  claim 6 , further comprising:
 a pair of lead wires that is connected to the first electrode and the second electrode, respectively; and   a controller that is electrically connected with the pair of lead wires.   
     
     
         9 . The micropump of  claim 1 , wherein:
 the volume of the second space is larger than the volume of the first space.   
     
     
         10 . The micropump of  claim 1 , further comprising:
 an on/off valve that is disposed in the connection channel; and   an anti-backflow member that is disposed in the fluid intake pipe and the fluid discharge pipe.   
     
     
         11 . The micropump of  claim 10 , wherein:
 the on/off valve is a piezoelectric valve that includes a first piezoelectric disk and a second piezoelectric disk that are disposed in parallel with the connection channel.   
     
     
         12 . The micropump of  claim 10 , wherein:
 the anti-backflow member is formed in a cone shape of which the inner diameter gradually increases from a side facing the fluid intake pipe to the opposite side facing the fluid discharge pipe.   
     
     
         13 . The micropump of  claim 10 , wherein:
 the anti-backflow member includes:   a deforming plate that is formed of a thin layer and has a fixed end and a free end; and   a fixing protrusion that is positioned ahead of the free end of the deforming plate in a forward direction toward the fluid discharge pipe from the fluid intake pipe.   
     
     
         14 . The micropump of  claim 1 , further comprising:
 an anti-backflow member that is disposed in the fluid intake pipe, the connection channel, and the fluid discharge pipe.   
     
     
         15 . The micropump of  claim 14 , wherein:
 the anti-backflow member is formed in a cone shape of which the inner diameter gradually increases from a side facing the fluid intake pipe to the opposite side facing the fluid discharge pipe.   
     
     
         16 . The micropump of  claim 14 , wherein:
 the anti-backflow member includes:   a deforming plate that is formed of a thin layer and has a fixed end and a free end; and   a fixing protrusion that is positioned ahead of the free end of the deforming plate in a forward direction toward the fluid discharge pipe from the fluid intake pipe.   
     
     
         17 . A method of operating the micropump of  claim 1 , comprising:
 a first section where the first deforming member expands from the minimum displacement to the maximum displacement and the second deforming member initially expands from the minimum displacement;   a second section where the first deforming member retracts from the maximum displacement and the second deforming member expands to the maximum displacement; and   a third section where the first deforming member retracts to the minimum displacement and the second deforming member retracts from the maximum displacement.   
     
     
         18 . The method of  claim 17 , wherein:
 the second deforming member starts to expand from the minimum displacement with a time difference from the maximum displacement position of the first deforming member in the first section.   
     
     
         19 . The method of  claim 17 , wherein:
 the minimum displacement position of the first deforming member has a time difference from the maximum displacement position of the second deforming member in the third section.   
     
     
         20 . The method of  claim 17 , wherein:
 an on/off valve is disposed in a connection channel of the micropump, and   the on/off valve opens the connection channel by operating simultaneously with the expansion of the second deforming member and closes the connection channel by operating simultaneously with that the second deforming member reaches the maximum displacement.   
     
     
         21 . A method of operating the micropump of  claim 1 , comprising:
 a first section where the first deforming member expands from the minimum displacement to the maximum displacement and the second deforming member initially expands from the minimum displacement;   a second section where the first deforming member retracts from the maximum displacement to the minimum displacement and the second deforming member expands to the maximum displacement; and   a third section where the first deforming member initially expands from the minimum displacement and the second deforming member retracts to the minimum displacement.   
     
     
         22 . The method of  claim 21 , wherein:
 the second deforming member starts to expand from the minimum displacement with a time difference from the maximum displacement position of the first deforming member in the first section.   
     
     
         23 . The method of  claim 21 , wherein:
 the maximum displacement position of the first deforming member agrees with the maximum displacement position of the second deforming member in the second section.   
     
     
         24 . The method of  claim 21 , wherein:
 an on/off valve is disposed in a connection channel of the micropump, and   the on/off valve opens the connection channel by operating simultaneously with the expansion of the second deforming member and closes the connection channel by operating simultaneously with that the second deforming member reaches the maximum displacement.   
     
     
         25 . A method of operating the micropump of  claim 1 , comprising:
 a first section where fluid is sucked into the first space by expanding the first deforming member from the minimum displacement to the maximum displacement;   a second section where fluid is sucked into the first space and the second space by retracting the first deforming member from the maximum displacement to the minimum displacement and expanding the second deforming member from the minimum displacement to the maximum displacement; and   a third section where the fluid in the first space and the second space is discharged by retracting the second deforming member from the maximum displacement to the minimum displacement.   
     
     
         26 . The method of  claim 25 , wherein:
 the maximum displacement position of the first deforming member agrees with the minimum displacement position of the second deforming member.   
     
     
         27 . The method of  claim 25 , wherein:
 an on/off valve is disposed in a connection channel of the micropump, and   the on/off valve opens the connection channel by operating simultaneously with the expansion of the second deforming member and closes the connection channel by operating simultaneously with that the second deforming member reaches the maximum displacement.