Mechanism for fixing a blood centrifuge bowl to a rotating spindle

A chuck for fixing a blood centrifuge bowl to a rotating spindle, the chuck having a central axis, the chuck comprising:

• a) a base plate having a transverse plane within the base plate that intersects the central axis at a right angle, the base plate having an upper surface, an outer periphery and a cam surface that extends upward from the upper surface of the base plate around the outer periphery of the base plate;
• b) at least one finger extending upward from the outer periphery of the base plate, the finger having a collar contact surface, a bowl contact surface and a cam contact surface and wherein the finger is made of a material with sufficient flexibility to allow the finger to move toward and away from the central axis;
• c) a collar having a main body, the collar having an upper side and a lower side, the main body being contoured to fit around the base plate, the main body including a finger contact surface that slopes inwardly from the main body moving from the lower side to the upper side, the finger contact surface shaped to contact the collar contact surface;
• whereby, downward movement of the collar causes the finger contact surface to contact the collar contact surface and move the finger toward the central axis of the chuck, and,
• whereby, contact between the cam surface and the cam contact surface prevents the finger from moving too far toward the central axis of the chuck.

A chuck for fixing a blood centrifuge bowl to a rotating spindle, the chuck having a central axis, the chuck comprising:

• a) a base plate having a transverse plane within the base plate that intersects the central axis at a right angle, the base plate having an upper surface, an outer periphery and at least one plunger bore formed in the base plate extending away from the central axis;
• b) at least one finger extending upward from the outer periphery of the base plate, the finger having a collar contact surface and a bowl contact surface and wherein the finger is made of a material with sufficient flexibility to allow the finger to move toward and away from the central axis;
• c) a collar having an upper side and a lower side, the collar having a main body, the main body being contoured to fit around the base plate and finger, the main body including:
• 1) a finger contact surface that slopes toward the central axis from the main body moving from the lower side to the upper side, the finger contact surface shaped to contact the collar contact surface;
• 2) a plunger capture wall formed at the lower edge of the main body, the plunger capture wall having a sloping pressure wall that slopes toward the central axis moving from the upper side to the lower side;
• d) at least one plunger located in the respective plunger bore and able to move along the plunger bore;
• whereby, movement of the chuck around the central axis produces centrifugal forces that cause the plunger to move away from the central axis in the plunger bore, and
• whereby, contact between the plunger and the plunger pressure wall causes downward movement of the collar, and,
• whereby, downward movement of the collar causes the finger contact surface to contact the collar contact surface and move the finger toward the central axis of the chuck.

A system for centrifuging blood comprising:

• a) a blood bowl having a central axis, an outer surface, an outer edge and a lower base;
• and,
• b) a chuck comprising:
• 1) a base having an outer periphery, the base having at least one finger extending upward from the outer periphery of the base, the finger having a collar contact surface and a bowl contact surface and wherein the finger is made of a material with sufficient flexibility to allow the finger to move toward and away from the central axis of the chuck;
• 2) a collar having a main body, the collar having an upper side and a lower side, the main body being contoured to fit around the base and finger, the main body including a finger contact surface that slopes inwardly from the main body moving from the lower side to the upper side, the finger contact surface shaped to contact the collar contact surface;
• whereby, downward movement of the collar causes the finger contact surface to contact the collar contact surface and move the finger toward the central axis of the chuck;
• and,
• whereby movement of the finger toward the central axis of the chuck causes the bowl contact surface to contact the outer surface of the blood bowl.

A system for centrifuging blood comprising:

• a) a blood bowl having a central axis, an outer surface, an outer edge and a lower base;
• and,
• b) a chuck for fixing a blood bowl to a rotating spindle, the chuck having a central axis, the chuck comprising:
• 1) a base plate having a transverse plane within the base plate that intersects the central axis at a right angle, the base plate having an upper surface, an outer periphery and a cam surface that extends upward from the upper surface of the base plate around the outer periphery of the base plate;
• 2) at least one finger extending upward from the outer periphery of the base plate, the finger having a collar contact surface, a bowl contact surface and a cam contact surface and wherein the finger is made of a material with sufficient flexibility to allow the finger to move toward and away from the central axis;
• 3) a collar having a main body, the collar having an upper side and a lower side, the main body being contoured to fit around the base plate and finger, the main body including a finger contact surface that slopes inwardly from the main body moving from the lower side to the upper side, the finger contact surface shaped to contact the collar contact surface;
• whereby, downward movement of the collar causes the finger contact surface to contact the collar contact surface and move the finger toward the central axis of the chuck and,
• whereby movement of the finger toward the central axis of the chuck causes the bowl contact surface to contact the outer surface of the blood bowl;
• and,
• whereby, contact between the cam surface and the cam contact surface prevents the finger from moving too far toward the central axis of the chuck.

A system for centrifuging blood comprising:

• a) a blood bowl having a central axis, an outer surface, an outer edge and a lower base;
• and,
• b) a chuck for fixing a blood bowl to a rotating spindle, the chuck having a central axis, the chuck comprising:
• 1) a base plate having a transverse plane within the base plate that intersects the central axis at a right angle, the base plate having an upper surface, an outer periphery and at least one plunger bore formed in the base plate extending away from the central axis;
• 2) at least one finger extending upward from the outer periphery of the base plate, the finger having a collar contact surface and a bowl contact surface and wherein the finger is made of a material with sufficient flexibility to allow the finger to move toward and away from the central axis;
• 3) a collar having an upper side and a lower side, the collar having a main body, the main body being contoured to fit around the base plate and finger, the main body including:
• a) a finger contact surface that slopes toward the central axis from the main body moving from the lower side to the upper side, the finger contact surface shaped to contact the collar contact surface;
• b) a plunger capture wall formed at the lower edge of the main body, the plunger capture wall having a sloping pressure wall that slopes toward the central axis moving from the upper side to the lower side;
• 4) at least one plunger located in the respective plunger bore and able to move along the plunger bore;
• whereby, movement of the chuck around the central axis produces centrifugal forces that cause the plunger to move away from the central axis in the plunger bore, and
• whereby, contact between the plunger and the plunger pressure wall causes downward movement of the collar, and,
• whereby, downward movement of the collar causes the finger contact surface to contact the collar contact surface and move the finger toward the central axis of the chuck and thereby contact and firmly hold the blood bowl.

A method of converting outwardly directed centrifugal forces into a downward bias on a collar comprising the steps of:

• a) providing a mass capable of moving away from a first central axis under the influence of centrifugal forces;
• b) providing a collar around the mass, the collar having a top and a bottom and an inwardly directed sloping surface, moving from top to bottom, the collar having a second central axis, the first and second central axes aligned when the collar is in position around the mass;
• c) positioning the collar so that the mass contacts the sloping surface when the mass is acted on by centrifugal forces;
• d) rotating the mass and collar around their aligned first and second central axes;
• whereby, centrifugal forces acting on the mass cause the mass to move away from the first axis into contact with the sloping surface;
• and,
• whereby, contact between the mass and the sloping surface causes the collar to be biased downwardly.

A method of converting downward movement on a collar into a inward movement of a finger comprising the steps of:

• a) providing a collar, the collar having a top and a bottom and an inwardly directed sloping surface, moving from bottom to top, the collar having a first central axis;
• b) providing at least one finger, the finger rotatable around a pivot point, the finger having a sloping surface contact point and an object contact point, the sloping surface contact point contacting the sloping surface, the object contact point being generally directed toward a second central axis, the finger rotating around the pivot point in response to contact between the sloping surface and the sloping surface contact point so that the object contact point moves toward the second axis;
• c) moving the collar downwardly;
• whereby, contact between the sloping surface and the sloping surface contact point moves the object contact point toward the second axis.

A method of converting outwardly directed centrifugal forces into inward movement of a finger comprising the steps of:

• a) providing a mass capable of moving away from a first central axis under the influence of centrifugal forces;
• b) providing a collar around the mass, the collar having a top and a bottom, a first inwardly directed sloping surface, moving from top to bottom, and a second inwardly directed sloping surface, moving from bottom to top, the collar having a second central axis, the first and second central axes aligned when the collar is in position around the mass;
• c) providing at least one finger, the finger rotatable around a pivot point the finger having a sloping surface contact point and an object contact point, the sloping surface contact point contacting the second inwardly directed sloping surface, the object contact point being generally directed toward the second central axis, the finger rotating around the pivot point in response to contact between the second inwardly directed sloping surface and the sloping surface contact point so that the object contact point moves toward the second axis;
• d) positioning the collar so that the mass contacts the sloping surface when the mass is acted on by centrifugal forces;
• e) rotating the mass and collar around their aligned first and second central axes;
• whereby, centrifugal forces acting on the mass cause the mass to move away from the first axis into contact with the first inwardly directed sloping surface;
• whereby, contact between the mass and the sloping surface causes the collar to move downwardly;
• and,
• whereby, contact between the second inwardly directed sloping surface and the sloping surface contact point moves the object contact point toward the second axis.