Pipetting device
View Patent ↗The present invention is related to a pipetting device with a throw-off system for detachably connecting with at least one pipette tip, at least one displacement device, a driving device for driving a displacement member of the displacement device and an adjustment device with a lead screw nut and a lead screw for adjusting the metering volume.
1. A pipetting device with
means ( 6 ) for detachably connecting with at least one pipette tip ( 7 ) and at least one displacement device ( 9 , 10 ) having a displacement chamber ( 9 ) and a displacement member ( 10 ) movably arranged therein, for sucking in and ejecting liquid into and out of the at least one pipette tip ( 7 ), or means for detachably connecting with at least one syringe with a cylinder and a plunger relocatable therein,
a lifting rod ( 15 ) for driving the displacement member ( 10 ) or the plunger of the at least one syringe,
with a driving means ( 14 ) for driving the lifting rod ( 15 ),
an adjustment device ( 5 ) for adjusting the metering volume with a lead screw nut ( 17 ) and a lead screw ( 16 ), wherein one of the components lead screw nut ( 17 ) and lead screw ( 16 ) is stationary with respect to the displacement chamber ( 9 ) or the cylinder of the connected syringe, and the other component is screwable with respect to the stationary component and has a stop ( 28 ), to which a counter-stop ( 27 ) of the lifting rod ( 15 ) is related,
wherein the lead screw ( 16 ) has a first external thread ( 23 . 1 ) and at least one further external thread ( 23 . 2 ) with a thread form shaped different than that of the first external thread ( 23 . 1 ), and the lead screw nut ( 17 ) has at least one related internal thread ( 24 ), and
wherein on the further external thread ( 23 . 2 ) of the lead screw ( 16 ) the lead screw nut ( 17 ) features at least in parts a distance (d) to the lead screw ( 16 ) in the radial direction (R) to the axis (A) of the lead screw ( 16 ) in the level (h) of the outer diameter and/or inner diameter of the external thread ( 23 . 2 , 23 ) of the lead screw ( 16 ).
2. A pipetting device according to claim 1 , characterised in that the related internal thread ( 24 ) of the lead screw nut ( 17 ) or the related external thread ( 23 ) of the lead screw ( 16 ) is produced or has been produced at least partly by screwing in the lead screw ( 16 ) into the lead screw nut ( 17 ) or by screwing on the lead screw nut ( 17 ) onto the lead screw ( 16 ).
3. A pipetting device according to claim 1 , wherein the first external thread ( 23 . 1 ) has another outer diameter and/or another inner diameter and/or another included thread angle and/or another pitch diameter and/or another shape of the thread form than the further external thread ( 23 . 2 ).
4. A pipetting device according to claim 1 , wherein in the whole adjustment range of the adjustment device ( 5 ), the further external thread ( 23 . 2 ) engages into the internal thread ( 24 ) produced by means of the lead screw ( 16 ).
5. A pipetting device according to claim 1 , wherein the lead screw ( 16 ) or the lead screw nut ( 17 ) is single started, and the further external thread ( 23 . 2 ) is added to the first external thread ( 23 . 1 ).
6. A pipetting device according to claim 1 , wherein the lead screw ( 16 ) or the lead screw nut ( 17 ) is multi started, and a first thread path is provided by the first external thread ( 23 . 1 ), and a further thread path is provided by the further external thread ( 23 . 1 ).
7. A pipetting device according to claim 1 , wherein the internal thread ( 24 ) is produced by screwing in the lead screw ( 16 ) into an even cylindrical bore ( 25 ) of the lead screw nut ( 17 ), or the external thread ( 23 ) is produced by screwing in an even cylindrical lead screw ( 16 ) into the lead screw nut ( 17 ).
8. A pipetting device according to claim 1 , wherein the internal thread ( 24 ) is produced by screwing in the lead screw ( 16 ) into a bore ( 25 ) of the lead screw nut ( 17 ), the bore ( 25 ) being provided with inwardly projecting noses, or the external thread ( 23 ) is produced by screwing in the lead screw ( 16 ), provided with outwardly projecting noses, into the lead screw nut ( 17 ).
9. A pipetting device according to claim 1 , wherein the internal thread ( 24 ) is produced by screwing in the lead screw ( 16 ) into a lead screw nut ( 17 ) provided with a partly prefabricated internal thread, or the external thread ( 23 ) is produced by screwing in the lead screw ( 16 ) which is provided with a partly prefabricated external thread.
10. A pipetting device according to claim 1 , wherein the external thread ( 24 ) or the internal thread is produced by machining and/or in a non-machining manner.
11. A pipetting device according to claim 1 , wherein the first external thread ( 23 . 1 ) is a thread with a triangular shape, and the further external thread ( 23 . 2 ) is a thread with a trapezoidal shape.
12. A pipetting device according to claim 1 , wherein the lead screw nut ( 17 ) is made at least in the region in which the internal thread ( 24 ) is produced by means of the lead screw ( 16 ) of a softer material than the lead screw ( 16 ) at least in the region of the external thread ( 23 ), or wherein the lead screw ( 16 ) is made at least in the region in which the external thread ( 23 ) is produced by means of the lead screw nut ( 17 ) of a softer material than the lead screw nut ( 17 ) at least in the region of the internal thread ( 24 ).
13. A pipetting device according to claim 1 , wherein the lead screw nut ( 17 ) is made of a plastic at least in the region in which the internal thread ( 24 ) is produced by means of the lead screw ( 16 ), or the lead screw ( 16 ) is made of a plastic at least in the region in which the external thread ( 23 ) is produced by means of the lead screw nut ( 17 ).
14. A pipetting device according to claim 1 , wherein the lead screw ( 16 ) producing the internal thread ( 24 ) is made of a metal at least in the region of the external threads ( 23 . 1 , 23 . 2 ), or the lead screw nut ( 17 ) producing the external thread ( 23 ) is made of a metal at least in the region of the internal threads ( 24 ).
15. A pipetting device according to claim 1 , wherein the torque for moving the lead screw ( 16 ) in the lead screw nut ( 17 ) is about 50 mNm at maximum.
16. A pipetting device according to claim 1 , characterised in that on the further external thread ( 23 . 2 ) of the lead screw ( 16 ), the lead screw nut ( 17 ) features a distance (d) to the lead screw ( 16 ) in the radial direction (R) to the axis (A) of the lead screw ( 16 ) in the level (h) of the outer diameter and/or inner diameter of the external thread ( 23 . 2 , 23 ) of the lead screw ( 16 ).
17. A pipetting device according to claim 1 , characterised in that the distance of the lead screw nut ( 17 ) to the lead screw ( 16 ) on the further external thread ( 23 . 2 ) of the lead screw ( 16 ) or the further internal thread ( 24 . 2 ) of the lead screw nut ( 17 ) in the radial direction (R) to the axis (A) of the lead screw ( 16 ) in the level (h) of the outer diameter and/or inner diameter of the external thread ( 23 . 2 , 23 ) of the lead screw ( 16 ) is greater than 0.015 mm.
18. A pipetting device according to claim 1 , characterised in that the distance of the lead screw nut ( 17 ) to the lead screw ( 16 ) on the further external thread ( 23 . 2 ) of the lead screw ( 16 ) is in the range from 0.020 mm to 0.060 mm.
19. A pipetting device with
means ( 6 ) for detachably connecting with at least one pipette tip ( 7 ) and at least one displacement device ( 9 , 10 ) having a displacement chamber ( 9 ) and a displacement member ( 10 ) movably arranged therein, for sucking in and ejecting liquid into and out of the at least one pipette tip ( 7 ), or means for detachably connecting with at least one syringe with a cylinder and a plunger relocatable therein,
a lifting rod ( 15 ) for driving the displacement member ( 10 ) or the plunger of the at least one syringe,
with a driving means ( 14 ) for driving the lifting rod ( 15 ),
an adjustment device ( 5 ) for adjusting the metering volume with a lead screw nut ( 17 ) and a lead screw ( 16 ), wherein one of the components lead screw nut ( 17 ) and lead screw ( 16 ) is stationary with respect to the displacement chamber ( 9 ) or the cylinder of the connected syringe, and the other component is screwable with respect to the stationary component and has a stop ( 28 ), to which a counter-stop ( 27 ) of the lifting rod ( 15 ) is related,
wherein the lead screw nut ( 17 ) has a first internal thread ( 24 . 1 ) and at least one further internal thread ( 24 . 2 ) with a thread form shaped different than that of the first internal thread, and the lead screw ( 16 ) has at least one related external thread ( 23 ), and
wherein on the further internal thread ( 24 . 2 ) of the lead screw nut ( 17 ), the lead screw nut ( 17 ) features at least in parts a distance (d) to the lead screw ( 16 ) in the radial direction (R) to the axis (A) of the lead screw ( 16 ) in the level (h) of the outer diameter and/or inner diameter of the external thread ( 23 . 2 , 23 ) of the lead screw ( 16 ).
20. A pipetting device according to claim 19 , wherein the first internal thread ( 24 . 1 ) has another outer diameter and/or another inner diameter and/or another included thread angle and/or another pitch diameter and/or another shape of the thread form than the or the further internal thread ( 24 . 2 ).
21. A pipetting device according to claim 19 , wherein in the whole adjustment range of the adjustment device ( 5 ), or the external thread ( 23 ) produced by means of the lead screw nut ( 17 ) engages into the further internal thread ( 24 . 2 ).
22. A pipetting device according to claim 19 , wherein the lead screw ( 16 ) or the lead screw nut ( 17 ) is single started, and the further internal thread ( 24 . 2 ) is added to the first internal thread ( 24 . 1 ).
23. A pipetting device according to claim 19 , wherein the lead screw ( 16 ) or the lead screw nut ( 17 ) is multi started, and the first internal thread ( 24 . 1 ), and a further thread path is provided by the further internal thread ( 24 . 2 ).
24. A pipetting device according to claim 19 , wherein or the first internal thread ( 24 . 1 ) is a thread with a triangular shape, and the further internal thread ( 24 . 2 ) is a thread with a trapezoidal shape.
25. A pipetting device according to claim 19 , characterised in that or on the further internal thread ( 24 . 2 ) of the lead screw nut ( 17 ), the lead screw nut ( 17 ) features a distance (d) to the lead screw ( 16 ) in the radial direction (R) to the axis (A) of the lead screw ( 16 ) in the level (h) of the outer diameter and/or inner diameter of the external thread ( 23 . 2 , 23 ) of the lead screw ( 16 ).
26. A pipetting device according to claim 19 , characterised in that or the further internal thread ( 24 . 2 ) of the lead screw nut ( 17 ) in the radial direction (R) to the axis (A) of the lead screw ( 16 ) in the level (h) of the outer diameter and/or inner diameter of the external thread ( 23 . 2 , 23 ) of the lead screw ( 16 ) is in the range from 0.020 mm to 0.060 mm.