Hollow needle for a sample pipettor

Patent metadata

Field	Value
Publication number	US-10040060-B2
Application number	US-201314031090-A
Country	US
Kind code	B2
Filing date	Sep 19, 2013
Priority date	Sep 24, 2012
Publication date	Aug 7, 2018
Grant date	Aug 7, 2018

Abstract

The invention relates to a hollow needle (1) for a sample pipettor in an automated analysis instrument, which sample pipettor is suitable for withdrawing sample liquid from a sealed sample vessel by virtue of the cover or the cap of the sample vessel being pierced by the hollow needle (1). The hollow needle (1) has a substantially straight cylindrical basic shape with a tip (8) for piercing a cover and enables a removal of sample liquid, comparatively less susceptible to errors, from a sample vessel in an automated analysis instrument. In the region of the tip (8) of the hollow needle (1), a number of faces (22, 26, 28, 30) have been introduced in such a way that the radial force components resulting at the respective faces (22, 26, 28, 30) during an axial movement into an elastic material cancel one another.

First claim

The invention claimed is:

1. A hollow needle for piercing a sealing device on a sample vessel, comprising:
a needle axis extending in an axial direction of the hollow needle;
a first axial portion having a first external diameter;
a second axial portion adjoining the first axial portion, the second axial portion having a conical shape; and
a third axial portion adjoining the second axial portion; wherein:
the third axial portion has a second external diameter greater than the first external diameter;
the first, second, and third axial portions have a hollow channel extending there through at a constant internal diameter, the hollow channel having a bend in the first axial portion;
the first axial portion has a first face inclined against the needle axis at a first angle of about 19 degrees with respect to the needle axis, the first face forming a tip for piercing the sealing device, the first face having an outlet of the hollow channel arranged laterally with respect to the needle axis;
the first axial portion has a second face inclined against the needle axis opposite the first face at a second angle of about 31 degrees with respect to the needle axis; and
the first face and the second face generate respective force components in a radial direction during an axial movement into the sealing device that cancel each other out.

2. The hollow needle as claimed in claim 1 , wherein the first axial portion has two to eight faces.

3. The hollow needle as claimed in claim 1 , wherein a line normal to the center of the first face and a line normal to the center of the second face lies in a plane with the needle axis.

4. The hollow needle as claimed in claim 1 , wherein the first face at least partly surrounds the outlet of the hollow channel.

5. The hollow needle as claimed in claim 1 , wherein the second axial portion has a third external diameter equal to the first external diameter adjacent the first portion and has a fourth external diameter equal to the second external diameter adjacent to the third portion.

6. The hollow needle as claimed in claim 1 , wherein the tip is offset from the needle axis.

7. A sample pipettor for an automated analysis instrument, the sample pipettor comprising:
the hollow needle of claim 1 ; and
a holder for attaching the hollow needle to a transfer arm.

8. An automated analysis instrument comprising:
the sample pipettor of claim 7 ;
a measurement system; and
a storage unit to store measurement results captured by the measurement system.

9. The hollow needle as claimed in claim 1 , wherein the second face has a smaller surface than the first face.

10. The hollow needle as claimed in claim 1 , wherein the first axial portion has two semicircular faces arranged symmetrically about the first face.

11. The hollow needle as claimed in claim 1 , wherein the third axial portion has an axial recess extending in the axial direction.

12. The hollow needle as claimed in claim 1 , wherein the bend has a bending radius of about 1.15 mm.

13. The hollow needle as claimed in claim 1 , wherein the first axial portion has an external diameter of about 1.2 mm.

14. The hollow needle as claimed in claim 1 , wherein the third axial portion has an external diameter of about 2.1 mm.

Assignees

• Siemens Healthcare Diagnostics Products Gmbh

Inventors

• Kressirer Rudolf
• Ziechner Eike

Classifications

• B01L3/021 Primary

  Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids · CPC title

• B01L2300/0838

  Capillaries · CPC title

• B01L2200/14

  Process control and prevention of errors · CPC title

• A61M5/3286

  Needle tip design, e.g. for improved penetration · CPC title

• B01L2200/0689

  Sealing · CPC title