Pipette with adjustable dosing volume

Patent metadata

Field	Value
Publication number	US-11602744-B2
Application number	US-202016993484-A
Country	US
Kind code	B2
Filing date	Aug 14, 2020
Priority date	Aug 15, 2019
Publication date	Mar 14, 2023
Grant date	Mar 14, 2023

Abstract

A pipette with an adjustable dosing volume comprises a housing connected to at least one seat configured to releasably hold a pipette tip. A displacement device is positioned within the housing and configured to aspirate and discharge liquid from the pipette tip. A stroke rod is coupled to the displacement element and configured to be longitudinally displaced relative to the housing to displace the displacement device. A catch sleeve is rotatably mounted within the housing and is connected to the stroke rod. An adjusting sleeve configured to engage a transducer shaft that is rotatably mounted within the housing and comprises a countershaft of a gearbox that is configured to be shifted between different shift stages. Each shift stage comprises different gear ratios between a rotational speed of the adjusting sleeve and a rotational speed of the catch sleeve. The different gear ratios enable coarse volume adjustment and fine volume adjustment.

First claim

The invention claimed is:

1. A pipette with an adjustable dosing volume comprising:
a housing comprising an upper end and an opposing lower end;
at least one seat connected to the housing and configured to releasably hold a pipette tip to the lower end of the housing;
a displacement device positioned within the housing and comprising,
a displacement chamber fluidly connected to the at least one seat, and
a displacement element configured to move within the displacement chamber to aspirate and discharge liquid from the pipette tip;

a stroke rod coupled to the displacement element and configured to be longitudinally displaced relative to the housing to displace the displacement element within the displacement chamber;
a control button configured to connect to the stroke rod to control movement of the stroke rod, wherein at least a portion of the control button projects from the housing;
a threaded spindle comprising at least one catch and defining a central spindle hole configured to guide the stroke rod;
a catch sleeve rotatably mounted within the housing and comprising an output shaft and at least one groove extending in a longitudinal direction that is configured to engage the at least one catch of the threaded spindle;
a counter configured to detect the rotation of the catch sleeve and display a dosing volume;
an adjusting sleeve rotatably mounted within the housing and comprising an input shaft;
an adjusting element accessible from an outside of the housing and connected to the adjusting sleeve; and
a transducer shaft rotatably mounted within the housing and comprising a countershaft of a gearbox, wherein the gearbox comprises,
a shifting device, and
a shift element accessible from outside of the housing, wherein the shift element is configured to shift the gearbox between different shift stages,

wherein each different shift stage comprises different gear ratios between a rotational speed of the adjusting sleeve and a rotational speed of the catch sleeve, and
wherein the different gear ratios enable coarse volume adjustment and fine volume adjustment.

2. The pipette according to claim 1 , wherein one of the adjusting sleeve and the catch sleeve include an outer circumference comprising a plurality of toothings with different diameters, wherein the transducer shaft comprises a plurality of toothings with different diameters, and wherein the shifting element is configured to cause the plurality of toothings of the transducer shaft to engage one of the plurality of toothings of the adjusting sleeve and the plurality of toothings of the catch sleeve.

3. The pipette according to claim 2 , wherein the counter comprises a drive gear configured to engage a first toothing on the outer circumference of the catch sleeve.

4. The pipette according to claim 1 , wherein:
the catch sleeve comprises a first toothing positioned on an outer circumference;
the adjusting sleeve comprises a second toothing on an outer circumference and a third toothing above the second toothing, wherein the second toothing has a different diameter than the third toothing; and
the transducer shaft comprises a fourth toothing configured to engage with the first toothing, a fifth toothing positioned above the fourth toothing, and a sixth toothing positioned above the fifth toothing, wherein the fifth toothing and the sixth toothing have different diameters.

5. The pipette according to claim 4 , wherein the shifting device is configured to displace the adjusting sleeve and the transducer shaft in an axial direction relative to each other to bring the second toothing into engagement with the fifth toothing, and wherein the third toothing is simultaneously disengaged from the sixth toothing.

6. The pipette according to claim 5 , wherein the shifting device is configured to displace the adjusting sleeve and the transducer shaft in an axial direction relative to each other to bring the third toothing into engagement with the sixth toothing and simultaneously disengage the second toothing from the fifth toothing, and wherein the displacement of the adjusting sleeve and the transducer shaft alters the rotational speed of the adjusting sleeve and the rotational speed of the catch sleeve can be altered.

7. The pipette according to claim 6 , wherein the fourth toothing has a same diameter and a same number of teeth as the fifth toothing.

8. The pipette according to claim 7 , wherein the first toothing and the second toothing have a same number of teeth and a same diameter.

9. The pipette according to claim 7 , wherein the first toothing the second toothing have a different number of teeth and a same diameter.

10. The pipette according to claim 6 , wherein the fourth toothing and the fifth toothing have different diameters.

11. The pipette according to claim 4 , wherein the shifting device is configured to displace the adjusting sleeve in an axial direction relative to the housing to bring the second toothing into engagement with the fifth toothing and simultaneously disengage the third toothing from the sixth toothing.

12. The pipette according to claim 11 , wherein the shifting device is configured to displace the adjusting sleeve in the axial direction relative to the housing to bring the third toothing into engagement with the sixth toothing and simultaneously disengage the second toothing from the fifth toothing.

13. The pipette according to claim 4 , wherein the shifting device is configured to displace the transducer shaft in an axial direction relative to the housing to bring the second toothing into engagement with the fifth toothing and simultaneously disengage the third toothing from the sixth toothing.

14. The pipette according to claim 13 , wherein the shifting device is configured to displace the transducer shaft in an axial direction relative to the housing to bring the third toothing into engagement with the sixth toothing and simultaneously disengage the second toothing from the fifth toothing.

15. The pipette according to claim 1 , further comprising a first spring device positioned within the housing and braced against one of the stroke rod and the displacement element.

16. The pipette according to claim 1 , further comprising a second spring device configured to adjust the shifting device into a certain shifting stage.

17. The pipette according to claim 1 , wherein the transducer shaft is positioned between the adjusting sleeve and the counter.

18. The pipette according to claim 1 , wherein the counter comprises one or more counter rollers having a rotational axis that is parallel to the adjusting sleeve.

19. The pipette according to claim 1 , wherein the adjusting element is an adjusting ring positioned at an upper end of the adjusting sleeve.

20. A pipette with an adjustable dosing volume comprising:
a housing;
at least one seat connected to the housing and configured to releasably hold a pipette tip;
a displacement device positioned within the housing and configured to aspirate and discharge liquid from the pipette tip;
a stroke rod coupled to the displacement device and configured to be longitudinally displaced relative to the housing to displace the displacement device;
a control button configured to connect to the stroke rod to control movement of the stroke rod, wherein at least a portion of the control button projects from the housing;
a threaded spindle defining a central spindle hole configured to guide the stroke rod;
a catch sleeve rotatably mounted within the housing and configured to engage the threaded

Assignees

• Eppendorf Ag

Inventors

• Molitor Peter
• Tesch Florian

Classifications

• B01L2300/026

  Drum counters · CPC title

• B01L3/0224 Primary

  having mechanical means to set stroke length, e.g. movable stops (B01L3/0231, B01L3/0234 take precedence) · CPC title

• B01L2200/0605

  Metering of fluids · CPC title

• B01L2200/12

  Specific details about manufacturing devices · CPC title

• B01L3/0275

  Interchangeable or disposable dispensing tips · CPC title