Disposable blood transfusion device

1. A blood transfusion device comprising:

a drip chamber ( 10 ) comprising a bottom outlet ( 113 );

a filter ( 40 ) fixedly disposed in the drip chamber ( 10 ); and

a float regulator ( 20 ) moveably disposed in the drip chamber ( 10 ) under the filter ( 40 ), the float regulator ( 20 ) comprising an inverted upper cup ( 21 ) including a top projection ( 212 ), a lower cup ( 22 ) secured to the upper cup ( 21 ), and a suction cup ( 23 ) secured to an underside of the lower cup ( 22 );

wherein an inner diameter of the upper cup ( 21 ) is greater than an outer diameter of the lower cup ( 22 );

wherein the projection ( 212 ) is configured to contact an underside of the filter ( 40 ) when blood from a blood bag ( 90 ) sufficiently fills the drip chamber ( 10 ); and

wherein the suction cup ( 23 ) is configured to fall to permanently close the outlet ( 113 ) when blood in the drip chamber ( 10 ) completely drains.

2. The blood transfusion device of claim 1 , wherein the projection ( 212 ) is cross shaped.

3. The blood transfusion device of claim 1 , wherein the upper cup ( 21 ) further comprises a peg ( 211 ) extending downward from a bottom center, and wherein the lower cup ( 22 ) comprises a hollow connector ( 221 ) through a bottom center complimentarily secured to the peg ( 211 ).

4. The blood transfusion device of claim 1 , wherein the filter ( 40 ) is cylindrical and comprises a top mounting member ( 41 ), a bottom support ( 42 ), two opposite posts ( 43 ) disposed between the mounting member ( 41 ) and the support ( 42 ), and a mesh structure ( 44 ), disposed between the mounting member ( 41 ) and the support ( 42 ) with the posts ( 43 ) being disposed on an outer surface of the mesh structure ( 44 ).