Apparatus for Separating a Composite Liquid Into At Least Two Components

Abstract

An apparatus for separating blood into blood components using a separation vessel satellite bags mounted on a centrifuge rotor and a balancing assembly for the centrifuge to compensate for changes to the center of gravity.

1 . An apparatus for separating at least one volume of a composite liquid into at least a first component and a second component, the apparatus comprising:
 a centrifuge having a rotation axis, comprising:
 a first container for storing a liquid at a distance from the rotation axis, whereby the storage of a liquid in the first container can cause an unbalance of the centrifuge; 
 a second container for storing a liquid at a distance from the rotation axis, whereby the storage of a liquid in the second container can cause an unbalance of the centrifuge; 
   a liquid transferring system for transferring a liquid between at least one of the first container and the second container whereby the transfer of a liquid can cause an unbalance of the centrifuge and wherein the liquid transferring system comprises a pump for transferring a separated component from at least one separation bag container in the first container into at least one satellite bag contained in the second container;   a balancing assembly for substantially neutralizing an unbalance of the centrifuge as it occurs comprising:
 a plurality of ponderous satellites; and 
 a housing for containing the ponderous satellites and defining a circular orbit along which the ponderous satellites can move substantially freely; 
   a memory for storing a separation speed at which a volume of composite liquid is separated into at least first and second components; and   a control unit programmed for:
 receiving the separation speed from the memory;
 causing the centrifuge to rotate at the separation speed and separate a volume of composite liquid in a separation bag contained in the first container into at least a first and second components; 
 causing the transferring system to transfer at least one portion of the first component into a satellite bag contained in the second container, whereby an unbalance of the centrifuge resulting from the transfer of liquid is substantially neutralized by the balancing assembly when it occurs. 
 
   
     
     
         2 . An apparatus according to  claim 1 , wherein the at least one balancing assembly further comprises a plurality of stops for temporarily stopping the ponderous satellites when the centrifuge does not rotate and the balancing assembly is inclined to no more than a predetermined angle with respect to a horizontal plane, and for allowing a movement of the ponderous satellites in the housing when the centrifuge is rotating at a speed that is above a determined speed. 
     
     
         3 . An apparatus according to  claim 2 , wherein the housing comprises a bottom wall, the plurality of ponderous satellites comprises a plurality of balls, and the stops comprise a plurality of dents in the bottom wall that are so shaped that a ball can partially engage in a dent. 
     
     
         4 . An apparatus according to  claim 3 , wherein the dents of the stops have a substantially conic shape. 
     
     
         5 . An apparatus according to  claim 2 , wherein the housing comprises a bottom wall, the plurality of ponderous satellites comprises a plurality of balls, and the stops comprise a plurality of protruding elements on the bottom wall. 
     
     
         6 . An apparatus according to  claim 2 , wherein the stops are so shaped that a ponderous satellite stopped by a stop gets released therefrom when the balancing assembly is inclined with respect to a horizontal plane of more than between about 15 degrees and about 20 degrees. 
     
     
         7 . An apparatus according to  claim 2 , wherein the number of stops is between about the number of ponderous satellites and about twice the number of ponderous satellites. 
     
     
         8 . An apparatus according to  claim 1 , wherein the number of ponderous satellites is selected so that the ponderous satellites fill a sector of the housing between about 90 degrees and about 270 degrees. 
     
     
         9 . An apparatus according to  claim 8 , wherein the ponderous satellites fill a sector of the housing of about 180 degrees. 
     
     
         10 . An apparatus according to  claim 1 , wherein the balancing assembly further comprises a dampening system for providing resistance to movement of the plurality of ponderous satellites and for dampening any noise caused by two or more ponderous satellites coming into contact. 
     
     
         11 . An apparatus according to  claims 10 , wherein the dampening system comprises a volume of a liquid that at least partially fills the housing of the balancing assembly. 
     
     
         12 . An apparatus according to  claim 11 , wherein the volume of liquid and the viscosity of the liquid are so selected as to contribute to a substantially accurate balancing and a substantially limited amplitude of a movement of the centrifuge at a resonance frequency thereof. 
     
     
         13 . An apparatus according to  claim 11 , wherein the volume of liquid fills between about 10% and about 90% of the housing. 
     
     
         14 . An apparatus according to  claim 11 , wherein the viscosity of the liquid is between about 200 cst and about 700 cst. 
     
     
         15 . An apparatus according to  claim 14 , wherein the viscosity of the liquid is about 350 cst. 
     
     
         16 . An apparatus according to  claim 1 , wherein the housing of the balancing assembly comprises a circular cavity having a generally rectangular cross-section. 
     
     
         17 . An apparatus according to  claim 1 , wherein the housing of the balancing assembly comprises a bottom wall, an inner lateral wall, an outer race and a top wall delimiting a circular cavity for containing the plurality of ponderous satellites, and wherein the outer race is made of hardened steel. 
     
     
         18 . An apparatus according to  claim 3 , wherein the plurality of ponderous satellites is made of hardened steel. 
     
     
         19 . An apparatus according to  claim 1 , wherein
 the first container comprises at least one separation compartment and the second container comprises at least one storage container, and   the at least one separation compartment is further apart from the rotation axis than the at least one storage container.   
     
     
         20 . An apparatus according to  claim 19 , wherein the centrifuge comprises a rotor comprising:
 a central storage member having a bottom and an upper portion, wherein the at least one storage container is included in the central storage member;   a peripheral storage member surrounding the central storage member and connected to the upper portion thereof, wherein the at least one separation compartment is included in the peripheral storage member; and   a shaft connected to the bottom of the central storage member.   
     
     
         21 . An apparatus according to  claim 20 , wherein the balancing assembly comprises an upper balancing assembly secured to the rotor around the central storage member underneath the peripheral storage member, so that a plane containing the upper balancing assembly is substantially perpendicular to the rotation axis of the centrifuge. 
     
     
         22 . An apparatus according to  claim 20 , wherein the balancing assembly comprises a lower balancing assembly that is connected to the shaft. 
     
     
         23 . An apparatus according to  claim 1 , wherein the liquid transferring system comprises a squeezing system for squeezing the at least one separation bag contained in the first container so as to cause a transfer of a separated component into at least one satellite bag contained in the second container. 
     
     
         24 . An apparatus according to  claim 23 , wherein the squeezing system comprises:
 at least one flexible hydraulic chamber included in the first container;   a hydraulic pumping station for pumping a hydraulic fluid in and out the at least one hydraulic chamber.   
     
     
         25 . An apparatus according to  claim 1 , wherein the transferring system transfers a liquid from at least one satellite bag contained in the second container into at least one separation bag contained in the first container. 
     
     
         26 . An apparatus according to  claim 25 , wherein the transferring system comprises a support for supporting at least one satellite bag within the second container so that the supported satellite bag has a lower portion that is closer to the axis of rotation than an upper portion thereof by which the supported satellite bag is connected to the separation bag, and so that a liquid contained in the supported satellite bag drains from the supported satellite bag into the separation bag under centrifugation forces when the centrifuge is rotated at a transfer rotation speed. 
     
     
         27 . An apparatus according to  claim 26 , wherein the support comprises:
 a wall that is inclined with respect to the rotation axis;   a securing member for securing an upper portion of the supported satellite bag to an upper part of the inclined wall so that the supported satellite bag containing a liquid that is secured to the inclined wall by the securing assembly is adjacent to the inclined wall.   
     
     
         28 . An apparatus according to  claim 27 , wherein the support comprises a cradle having:
 a body comprised of a portion of a generally frusto-conical wall inclined with respect to the rotation axis, and   a bottom wall connected to the frusto-conical wall comprising a curved portion having a concavity oriented towards the rotation axis.   
     
     
         29 . An apparatus according to  claim 27 , wherein the securing member comprises:
 a bag holder having an elongated body having:
 a hanger for removably holding the least one satellite bag by an upper part thereof; and 
   a first locking element for removably securing the elongated body to the inclined wall, and   a second locking element integral with the inclined wall, complementary to the first locking element.   
     
     
         30 . An apparatus according to  claim 25 , further comprising:
 a memory for storing a transfer speed at which a volume of liquid in a satellite bag contained in the second container is transferred into a separation bag contained in the first container; and   the control unit is programmed for:
 receiving the transfer centrifugation speed from the memory; 
 causing the centrifuge to rotate at the transfer centrifugation speed so as to transfer at least a portion of a liquid in a satellite bag contained in the second container into a separation bag contained in the first container, whereby an unbalance of the centrifuge resulting from the transfer of liquid is substantially neutralized by the balancing assembly when it occurs.