| 摘要 |
<p>The centrifuge is a vessel with a height of 25-50 mm (75-125% of its radius), with the side wall enclosing the separation chamber. The speed of rotation (2omega ) is 500 rad/second so the liquid flow is at least 100 ml/minute. The materials and dimensions of the circuits are chosen so traction exerted on them is 0.7 N/mm 2>, the modulus of elasticity is 5 N/mm 2> and the resistance to fatigue is 1.5 N/mm 2> : The centrifuge has a circular centrifuge (2) for the liquid which has at least three channels (4,5,6) connecting its center to a peripheral separation chamber (3), means (1,23-33) of driving the centrifuge in rotation, and three channels (4a,5a,6a) made of elastically deformable material with one end fixed to each of the three channels in the centrifuge. The channels each form an open circuit around the centrifuge, with the second end coaxial with the first and fixed angularly. One channel is connected to the source of the liquid to be centrifuged and the other two act to recover the different density components produced by the centrifuge. The angular speed of rotation is omega and the device includes a means of turning each circuit concentrically about the centrifuge at an angular speed omega . The vessel has an inner and an outer vessel which are welded or glued together and which contain the channels and the separation chamber. The three channels are integrated into the same tube (7), whose diameter does not exceed 7 mm. The sections of the three channels are elliptical, with the major axes tangential to a circle which is concentric with the longitudinal axis of the tube. A detector on one of the channels detects the purity of the liquid in the pipe and as a result controls the flow using a valve. A photoelectric detector measures the frontier between the blood cells and the plasma. Friction is reduced by coating the tube with silica on a PVC base and/or reduction of the contact surface using spiral grooves. The liquid is pressurized to overcome pressure losses in the system.</p> |
