Blood pump

Claim 1

A BLOOD PUMP COMPRISING A PUMP BODY HAVING A HORIZONTAL CENTRAL AXIS, A U-SHAPED GUIDE SEAT MOUNTED ON SAID BAODY WITH THE ARC-SHAPED CENTRAL PORTION THEREOF DISPOSED BELOW AND CENTERED ABOUT SAID CENTRAL AXIS, A FLEXIBLE RESILIENT U-SHAPED TUBE SEATED ON SAID GUIDE SEAT AND HAVING ITS ENDS EXTENDING UPWARDLY ON OPPOSITE SIDES OF SAID CENTRAL AXIS, MEANS ON THE UPPER PORTION OF SAID PUMP BODY FOR SUPPORTING THE ENDS OF SAID TUBE, A PLURALITY OF PRESSURE ROLLERS MOUNTED ON SAID BODY WITH THEIR AXES IN SPACED PARALLEL RELATION TO SAID TUBE, MEANS ROTATIONAL MOVEMENT ABOUT THE LATTER AND IN ENGAGEMENT WITH THE ARC-SHAPED CENTRAL PORTION OF SAID TUBE, MEANS SUPPORTING SAID PRESSURE ROLLERS FOR MOVEMENT AS A WHOLE ABOUT PIVOTAL POINTS OFFSET FROM LINES CONNECTING SAID ROLLERS AXES WITH SAID CENTRAL AXIS, AND MEANS SAID TUBE BIASING EACH PRESSURE ROLLER INTO CONTACT WITH SAID TUBE WITH A GIVEN, SUBSTANTIALLY CONSTANT BEARING PRESSURE, SAID TUBE HAVING A FLATTISH, CONVEXO-CONVEX SHAPE AND INCLUDING AN OUTER WALL SEATED ON SAID GUIDE SEAT AND AN INNER WALL ENGAGED BY SAID PRESSURE ROLLERS, SAID FLATTISH WALLS BEING SUBSTANTIALLY UNIFORM IN THICKNESS THROUGHOUT THEIR WIDTHS, BEING OPPOSITELY CONVEX AND MEETING AT THEIR SIDE EDGES IN ACUTE ANGLES, SAID TUBE ALONG THE LONGITUDINAL LINES OF JUNCTURE OF THE WALLS THEREOF BEING OF SUBSTANTIALLY THE SAME THICKNESS AS IN THE WALLS THEREOF AND HAVING IN CROSS-SECTION A TRANSVERSE AXIS PARALLEL TO SAID CENTRAL AXIS AND SUBSTANTIALLY GREATER IN LENGTH THAN ITS CONJUGATE AXIS AND SUCH THAT ALL SYMMETRICALLY OPPOSITE PORTIONS OF THE WALLS THEREOF COME INTO CONTACT WHEN THE TUBE IS FLATTENED BY A ROLLER TO COMPLETELY CLOSE THE TUBE WITHOUT LEAVING ANY LATERAL OPENINGS, THE OUTER WALL OF SAID TUBE HAVING A CENTRAL LONGITUDINALLY EXTENDING INTEGRAL FIN OF SUBSTANTIAL CORSS-SECTIONAL AREA FOR SECURING SAID TUBE TO SAID GUIDE SEAT, AND THE INNER WALL OF SAID TUBE BEING SMOOTH TO ENABLE THE ROLLERS TO UNIFORMLY CONTACT THE SAME THROUGHOUT ITS WIDTH.