Micro peristaltic pump

Abstract

A circular arc shaped flow path ( 21 ) is formed as a microfluidic flow path in a sheet-like microfluidic chip ( 20 ). A roller ( 15 ) on a rotor ( 10 ) is pressed against the circular arc shaped flow path ( 21 ) in the microfluidic chip ( 20 ), the rotor ( 10 ) is rotary-driven by a driving motor 4 , and the circular arc shaped flow path ( 21 ) is caused to make a peristaltic motion by rotation of the rotor ( 10 ), to send a liquid in the flow path. On the flat surface of the rotor ( 10 ), a plurality of rollers ( 15 ) are held so as to be pressed in contact with the circular arc shaped flow path ( 21 ), to freely rotate on the flat surface perpendicular to a rotary shaft ( 13 ) of the rotor ( 10 ). The circular arc shaped flow path ( 21 ) is disposed along the rotational trajectory of the plurality of rollers ( 15 ).

1 . A micro peristaltic pump comprising:
 a base having a chip housing portion;   a sheet-like microfluidic chip housed in the chip housing portion, and having a circular arc shaped flow path which swells out of a flat surface in a substantially mountain shape at its cross section, to be formed into a circular arc shape:   a rotor installed in the base so as to be able to he rotary-driven opposite the flat surface of the microfluidic chip a plurality of free-rotating bodies held so as to be pressed in contact with the circular arc shaped flow path to he freely rotatable on a flat surface perpendicular to a rotary shaft of the rotor:   a rotary driving means which is attached to an attaching portion of the base, and rotatory-drives the rotor: and   a solid member fixed to the base so as to cover the microfluidic chip, wherein   the circular arc shaped flow path is formed such that its radius is the same as a radius of the rotational trajectory of the free-rotating bodies,   the rotor is installed so as to be rotatable in an opening portion provided near the chip housing portion of the base,   the sheet-like microfluidic chi is house n the chip housing portion with the circular arc shaped flow path faced toward the rotor,   the solid member is fixed to the base so as to cover the microfluidic chi) from a side opposite to the free-rotating bodies on the rotor and so as to be detachable by a retainer, and   the microfluidic chip is exposed so as to be detachable when the solid member is detached.   
     
     
         2 . (canceled) 
     
     
         3 . The micro peristaltic pump according to  claim 1 , wherein a spring holding portion v tit into an output shaft of the rotary driving means, a spring is mounted between the spring holding portion and the rotor, and the free-rotating bodies on the rotor are pressed against the circular arc shaped flow path in the microfluidic chip, to be biased by the spring. 
     
     
         4 . The micro peristaltic pump according to  claim 1 , wherein a plurality of rollers are disposed as the free-rotating bodies so as to locate outer circumferential surfaces of the rollers on the flat surface perpendicular to the rot-my shaft of the rotor, and to slightly protrude from the flat surface of the rotor to be capable of pressing the outer circumferential surfaces against the circular arc shaped flow path, and the rollers are rotatably-pivotally supported via spindles radially installed on the rotor. 
     
     
         5 . The micro peristaltic pump according to Claim I, wherein a plurality of balls are rotatable housed in retention holes provided in the flat surface of the rotor, and a part of the ball slightly protrudes from the flat surface of the rotor, and the outer circumferential surface of the ball is pressed in contact with the circular arc shaped flow path in the microfluidic chip. 
     
     
         6 . The micro peristaltic pump according to  claim 1 , wherein the circular arc shaped flow path in the microfluidic chip is formed such that two polymeric elastic sheets are superposed, and the two polymeric elastic sheets are bonded to one another in a state in which one of the polymeric elastic sheets on a side with which the free-rotating bodies come into contact is caused to bow at a circular arc shaped portion of the flow path, so as to swell out to be a mountain shape. 
     
     
         7 . The micro peristaltic pump according to  claim 4 , wherein the roller on the rotor is formed into a substantially circular truncated cone shape such that circumferential velocities at an inner circumferential side and an outer circumferential side of the roller are the same during rotation, and a spindle of the roller is pivotally supported in a sloped manner such that the outer circumferential surface of the roller is parallel to the surface of the circular arc shaped flow path in the microfluidic chip. 
     
     
         8 . The micro peristaltic pump according, to  claim 1 , wherein three free-rotating bodies are installed at intervals of approximately 120 degrees on the rotor, and the circular arc shaped flow path in the microfluidic chip is formed into a circular arc shape within an angular range of approximately 240 degrees. 
     
     
         9 . (canceled) 
     
     
         10 . (canceled) 
     
     
         11 . The micro peristaltic pump according to  claim 1 , wherein, as the solid member, a transparent plate-like solid cover body is fixed to the base by a retainer so as to be detachable from a side opposite to the free-rotating bodies, so as to cover the circular arc shaped flow path.