Sample analysis apparatus

1. Apparatus for analysis of liquid samples, comprising:

a support ( 4 ) for carrying, in a vertical position, plural sample tubes;

a removal and distribution unit ( 8 ) for removing from each carried sample tube a portion of a contained liquid sample and for distributing a fraction of the removed portion into at least one receptacle ( 74 ) as a distributed fraction,

said removal and distribution unit comprising a hollow needle ( 45 ) connected to an aspiration/delivery means ( 47 ) and fixed in vertical position to a vertically movable needle carrier ( 48 ), and drive means ( 53 , 54 , 57 , 58 , 59 , 61 ) to move the needle carrier,

said support ( 4 ) comprising a circular plate with peripheral tube carriers ( 5 ),

each tube carrier comprising a recess with a vertical access to receive and support a sample tube,

said circular plate being adapted to turn about a vertical axis to bring in position successively an selectively the tube carriers ( 5 ) to a workstation where the removal and distribution unit ( 8 ) is located such that the removal and distribution unit can act on a positioned sample tube ( 6 ) brought to and positioned in the workstation,

each tube carrier ( 5 ) connected to the circular plate ( 4 ) by a connection ( 31 ) with two degrees of freedom, a first of the two degrees of freedom being a vertical translatory movement and a second of the two degrees of freedom being a freedom of movement of rotation about a horizontal axis oriented tangentially relative to the circular plate,

a support means ( 44 ) adapted to support the tube carrier ( 5 ),

each tube carrier ( 5 ) constituted by a cylindrical sleeve ( 24 ) and two pivots ( 25 ) defining the horizontal axis with two degrees of freedom,

an end of each cylindrical sleeve ( 24 ) supported by a mounting member ( 28 ) secured to the circular plate,

each of the two pivots ( 25 ) resiliently supported in a vertical notch ( 32 ) by a flexible spring ( 33 ).

2. Apparatus for analysis of liquid samples, comprising:

a support ( 4 ) for carrying plural sample tubes;

a removal and distribution unit ( 8 ) for removing from each carried sample tube a portion of a contained liquid sample,

said removal and distribution unit comprising a hollow needle ( 45 ) connected to an aspiration/delivery means ( 47 ),

said support ( 4 ) comprising a circular plate with peripheral tube carriers ( 5 ),

each tube carrier comprising a recess with a vertical access to receive and support a sample tube,

said circular plate being adapted to turn about a vertical axis to bring in position successively the tube carriers ( 5 ) to the removal and distribution unit ( 8 ),

each tube carrier ( 5 ) connected to the circular plate ( 4 ) by a connection ( 31 ) with two degrees of freedom, a first of the two degrees of freedom being a vertical translatory movement and a second of the two degrees of freedom being a freedom of movement of rotation about a horizontal axis oriented tangentially relative to the circular plate,

a support means ( 44 ) adapted to support each tube carrier ( 5 ),

each tube carrier ( 5 ) constituted by cylindrical sleeve ( 24 ) and two pivots ( 25 ) defining the horizontal axis with two degrees of freedom,

an end of each cylindrical sleeve ( 24 ) supported by a mounting member ( 28 ) secured to the circular plate,

each of the two pivots ( 25 ) resiliently supported in a vertical notch ( 32 ) by a flexible spring ( 33 ).

3. Apparatus for analysis of liquid samples in sample tubes ( 6 ) closed by a pierceable stopper ( 7 ), comprising:

a support ( 4 ) adapted to support, in a vertical position, sample tubes closed by pierceable stoppers ( 7 );

a removal and distribution unit ( 8 )

i) to remove, from each sample tube supported by the support, a portion of a liquid sample contained in each sample tube, the removal creating a removed portion of the liquid sample, and

ii) to distribute at least a fraction of the removed portion of the liquid sample into at least one receptacle ( 74 ) for treatment and/or analysis as a distributed fraction,

said removal and distribution unit comprising

i) a hollow needle ( 45 ) connected to an aspiration/delivery means ( 47 ) and fixed in vertical position to a vertically movable needle carrier ( 48 ), and

ii) drive means ( 53 , 54 , 57 , 58 , 59 , 61 ) to move the needle carrier and needle vertically between a first position with a lower end of the needle located at a higher level than a stopper of a positioned sample tube carried by the support, and a second position with the lower end of the needle located within a liquid contained in said positioned sample tube,

said support ( 4 ) constituted by a circular plate with a periphery and provided with several tube carriers ( 5 ) disposed at intervals about the periphery,

each tube carrier comprising a recess with a vertical access to receive and support individual ones of the sample tubes,

said circular plate being adapted to turn about a vertical axis to bring in position successively and selectively the tube carriers ( 5 ) to a workstation where the removal and distribution unit ( 8 ) is located such that the removal and distribution unit can act on a positioned sample tube ( 6 ) supported by the tube carrier brought to and positioned in the workstation,

plural connections ( 31 ), each tube carrier ( 5 ) connected to the circular plate ( 4 ) by a respective one of the connections ( 31 ),

each of the connections having two degrees of freedom, a first of the two degrees of freedom being a vertical translatory movement and a second of the two degrees of freedom being a freedom of movement of rotation about a horizontal axis oriented tangentially relative to the circular plate,

a support means ( 44 ), disposed at the workstation, adapted to support from below the tube carrier ( 5 ) brought to and positioned in the workstation,

each tube carrier ( 5 ) constituted by cylindrical sleeve ( 24 ) open at an upper end and closed at a lower end and comprising, adjacent the upper end of the corresponding cylindrical sleeve, two aligned pivots ( 25 ) defining the horizontal axis of the respective connection ( 31 ),

the upper end of each cylindrical sleeve ( 24 ) being disposed between two legs ( 26 , 27 ) of a mounting member ( 28 ) in the form of a fork, the corresponding fork secured to the circular plate ( 4 ) with the corresponding two legs ( 26 , 27 ) extending radially outwardly of said circular plate, the two pivots ( 25 ) of each cylindrical sleeve ( 24 ) being supported respectively by the corresponding two legs of the corresponding mounting member ( 28 ),

each of the two legs ( 26 , 27 ) of the corresponding mounting member ( 28 ) comprising a vertical notch ( 32 ) engaging a respective one of the two pivots ( 25 ) of the corresponding cylindrical sleeve ( 24 ),

each of the corresponding two pivots ( 25 ) resiliently supported, in a respective one of the vertical notches ( 32 ), by a flexible spring ( 33 ).

4. Apparatus according to claim 3 , characterized in that the cylindrical tube-carrying sleeves ( 24 ) are of a transparent material so as to permit reading an individual identification code ( 39 ) carried by a label ( 38 ) fixed to each sample tube ( 6 ) by a code reader ( 41 ) installed at a predefined angular position relative to the vertical axis of rotation of the circular plate ( 4 ).

5. Apparatus according to claim 3 , characterized in that each cylindrical tube-carrying sleeve ( 24 ) comprises, in a cylindrical wall, a wide window ( 42 ) permitting reading an individual identification code ( 39 ) carried by a label ( 38 ) fixed to each sample tube ( 6 ) by code reader ( 41 ) installed at a fixed station in a predetermined angular position relative to the vertical axis of rotation of the circular plate ( 4 ).

6. Apparatus according to claim 3 , characterized in that each vertical notch ( 32 ) is formed in an upper surface of a corresponding leg ( 26 or 27 ) and the corresponding flexible spring ( 33 ) supports the corresponding pivot ( 25 ).

7. Apparatus according to claim 6 , characterized in that each mounting member ( 28 ) carries a removable retaining means ( 34 ), each removable retaining means, in service, retaining each of the corresponding two pivots ( 25 ) in the respective vertical notch ( 32 ).

8. Apparatus according to claim 3 , characterized in that each vertical notch ( 32 ) is formed in a lower surface of a corresponding leg ( 26 or 27 ) an each flexible spring ( 33 ) is constituted by a flexible blade with one end fixed to a lower surface of said corresponding leg and another end that resiliently supports and retains a corresponding pivot ( 25 ) in the respective vertical notch.

9. Apparatus according to claim 3 , characterized in that,

each said cylindrical sleeve is a cylindrical tube-carrying sleeve having a maximum breadth of vertical movement,

the support means ( 44 ) is constituted by a fixed stop disposed below a lower sleeve end of each cylindrical tube-carrying sleeve ( 24 ) brought to and positioned in the workstation, at a vertical distance (d) from said lower sleeve end, said lower sleeve end being smaller than said maximum breadth of vertical movement as permitted by said respective connection ( 31 ) and by the corresponding flexible spring ( 33 ) when the needle ( 45 ) of the removal and distribution unit ( 8 ) exerts a vertical penetration force, directed downwardly, on a stopper ( 7 ) of an installed sample tube ( 6 ) installed in any of said cylindrical tube-carrying sleeves ( 44 ).

10. Apparatus according to claim 3 , characterized in that each vertical notch ( 32 ) is formed in the upper surface of the corresponding leg ( 26 or 27 ) of the corresponding mounting member ( 28 ) and each pivot ( 25 ) rests on the bottom of the corresponding vertical notch.

11. Apparatus according to claim 10 , characterized in that the support means ( 44 ) is constituted by a wedge, which can be moved by an actuator ( 113 ) between a first position in which said wedge does not interfere with the cylindrical tube-carrying sleeves ( 24 ) when the circular plate ( 4 ) is rotated, and a second position in which said wedge is in contact with the lower end of one cylindrical tube-carrying sleeve brought to and positioned in the workstation and supports said one cylindrical sleeve in a vertical position such that the two pivots ( 25 ) of said one cylindrical sleeve no longer rest on the bottom of corresponding vertical notches ( 32 ).

12. Apparatus according to claim 11 , characterized in that said wedge ( 44 ) is constituted by a piece in the form of a wedge which can slide, under control of the actuator ( 113 ), over a fixed support and horizontal guidance surface ( 11 a ).

13. Apparatus according to claim 12 , characterized in that each mounting member ( 28 ) comprises an abutment means ( 114 ) adapted to prevent the one cylindrical tube-carrying sleeve ( 24 ) from pivoting about the horizontal axis and to hold said one cylindrical sleeve in a vertical position when the wedge ( 44 ) is moved from the first to the second position by the actuator ( 113 ) and comes in the course of this movement into contact with the lower end of said one cylindrical sleeve.

14. Apparatus according to claim 3 , characterized in that the circular plate ( 4 ) is connected to drive means ( 19 , 21 , 22 , 23 ) adapted to turn said circular plate selectively at a first relatively high speed to submit to centrifugation the liquid samples contained in the sample tubes ( 6 ) carried by the circular plate, and at a second substantially slower speed than the first speed, to bring and position successively and selectively said sample tubes to and in the workstation.