Sampling with fitting between needle and housing

Patent metadata

Field	Value
Publication number	US-12507925-B2
Application number	US-202118011127-A
Country	US
Kind code	B2
Filing date	Jun 22, 2021
Priority date	Jun 30, 2020
Publication date	Dec 30, 2025
Grant date	Dec 30, 2025

Abstract

A sampling unit includes a needle for aspirating a sample fluid, a housing, and a fitting. The needle includes a needle tip and a needle channel through the needle for guiding the aspirated sample fluid. The needle channel opens at the needle tip. The housing includes a housing cavity and a housing channel opening into the housing cavity. The fitting includes a fitting cavity and a fitting channel. The fitting is configured for sealingly receiving the needle tip into the fitting cavity and for being inserted into the housing cavity, so that the fitting channel on one side fluidically couples to the needle channel and on another side couples to the housing channel.

First claim

The invention claimed is:

1 . A sampling unit, comprising:
a needle configured for aspirating a sample fluid, wherein the needle comprises a needle tip and a needle channel through the needle for guiding the aspirated sample fluid, and wherein the needle channel opens at the needle tip; a housing comprising a housing cavity and a housing channel opening into the housing cavity; and a fitting having a fitting cavity and a fitting channel, wherein: the fitting comprises an external tapered shape extending on a lateral side of the fitting and decreasing in diameter towards an end of the fitting channel; the housing cavity comprises an internal tapered shape decreasing in diameter towards the housing channel; the fitting is configured to sealingly receive the needle tip into the fitting cavity and to be inserted into the housing cavity, so that the fitting channel on one side fluidically couples to the needle channel and on another side couples to the housing channel; and the needle, the housing, and the fitting are configured such that, when the needle tip is received into the fitting cavity and the fitting is inserted into the housing cavity, the needle provides an axial force that presses the external tapered shape of the fitting against the internal tapered shape of the housing cavity to provide a sealing between the fitting and the housing.

2 . The sampling unit of claim 1 , wherein:
the housing comprises a valve comprising a plurality of ports and being configured for switching one or more fluidic connections between the plurality of ports; and one of the plurality of ports is provided by or at least fluidically coupled to the housing cavity.

3 . The sampling unit of claim 1 , wherein the fitting is configured to provide a sealing fluidic coupling between the needle channel and the housing channel, when the needle tip is received into the fitting cavity, the fitting is inserted into the housing cavity, and the needle is pressed against the housing.

4 . The sampling unit of claim 3 , comprising at least one of:
a coupling between the needle tip and the fitting cavity is provided by a cone-to-cone coupling; a coupling between the fitting and the housing cavity is provided by a cone-to-cone coupling.

5 . The sampling unit of claim 1 , comprising at least one of:
the needle comprises a tapered shape comprising an external cone extending on a lateral side of the needle tip and decreasing in diameter towards an end of the needle tip; the fitting cavity comprises a tapered shape comprising an internal cone decreasing in diameter towards the one end of the fitting channel; the external tapered shape of the fitting comprises an external cone; the internal tapered shape of the housing cavity comprises an internal cone.

6 . The sampling unit of claim 5 , wherein the fitting is configured to provide a sealing fluidic coupling between the needle channel and the housing channel when the needle is pressed against the housing, by coupling the external cone of the needle to the internal cone of the fitting cavity, and by coupling the external cone of the fitting to the internal cone of the housing cavity.

7 . The sampling unit of claim 1 , comprising at least one of:
the needle comprises an elongated shape; the needle comprises a cylindrical shape; the needle channel is configured for at least partly buffering the aspirated sample fluid; the housing channel comprises a conduit; the fitting is configured as a needle seat for seating the needle.

8 . The sampling unit of claim 1 , wherein the fitting comprises a channel element comprising at least a portion of the fitting channel, and further comprising at least one of:
the channel element is configured for providing an axial alignment of the needle channel opening at the needle tip and the fitting channel opening into the fitting cavity; the channel element is configured to at least substantially maintain a diameter of the fitting channel when the needle is pressed against the housing; the channel element is configured to at least substantially maintain a value of flow restriction provided by the fitting channel when the needle is pressed against the housing; the channel element comprises one or more materials selected from the group consisting of: a ceramic material; hardened steel; and a nickel-cobalt based alloy; the channel element comprises a tapered shape comprising an external cone extending on a lateral side of the fitting and decreasing in diameter towards the other end of the fitting channel.

9 . The sampling unit of claim 1 , wherein the sampling unit is a sample injector for a chromatography system comprising a mobile phase drive and a separation unit, the mobile phase drive is configured for driving a mobile phase through the separation unit, the separation unit is configured for chromatographically separating compounds of a sample fluid in the mobile phase, and the sample injector is configured for injecting the sample fluid into the mobile phase.

10 . A fluid separation system for separating compounds of a sample fluid in a mobile phase, the fluid separation system comprising:
a mobile phase drive configured to drive the mobile phase through the fluid separation system; a separation unit configured to separate compounds of the sample fluid in the mobile phase; and the sampling unit of claim 1 , configured to introduce the sample fluid into the mobile phase.

11 . The fluid separation system of claim 10 , further comprising at least one of:
a detector configured to detect separated compounds of the sample fluid; a collection unit configured to collect separated compounds of the sample fluid; a data processing unit configured to process data received from the fluid separation system; a degassing apparatus configured to degas the mobile phase.

12 . A method for sampling, the method comprising:
providing the sampling unit of claim 1 ; aspirating the sample fluid via the needle; inserting the fitting into the housing cavity; penetrating at least a portion of the needle tip into the fitting cavity; pressing the needle against the housing so that the fitting channel on one side fluidically couples to the needle channel and on another side fluidically couples to the housing channel; and injecting at least a portion of the aspirated sample fluid via the fitting channel into the housing channel.

13 . The method of claim 12 , further comprising:
injecting at least a portion of the sample fluid contained in the housing channel into a mobile phase; and chromatographically separating the sample fluid in the mobile phase.

14 . A non-transitory computer-readable medium with instructions stored thereon, that when executed by a processor, control the steps of aspirating, inserting, penetrating, pressing, and injecting according to the method of claim 12 .

15 . The sampling unit of claim 1 , wherein the housing cavity comprises an internal thread interacting with an external thread of the fitting for coupling the fitting to the housing.

16 . The sampling unit of claim 1 , wherein the fitting comprises, in a region where the needle tip abuts to the fitting cavity, a material being softer than a material of the needle tip.

17 . The sampling unit of claim 1 , wherein the fitting comprises a first element and a second element, wherein the first element is configured to receive the needle tip, the second element is configured to mechanically couple to and engage with the housing cavity, and the first element is pivotally coupled with the second element to allo

Assignees

• Agilent Technologies Inc

Inventors

• Ortmann Thomas
• Lang Michael

Classifications

• A61B5/14

  Devices for taking samples of blood (hypodermic syringes A61M5/00); Measuring characteristics of blood in vivo, e.g. gas concentration within the blood, pH-value of blood (measuring of blood pressure A61B5/02; non-radiation detecting or locating of foreign bodies in blood A61B5/06) · CPC title

• G01N30/24

  Automatic injection systems · CPC title

• B01D15/14

  relating to the introduction of the feed to the apparatus · CPC title

• G01N2030/185

  specially adapted to seal the inlet · CPC title

• A61B5/15 Primary

  Devices for taking samples of blood · CPC title