US4393726A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sampling valve useful in liquid chromatography
Assignee: PE Manufacturing GmbH
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Filing: 1981-09-23
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Granted: 1983-07-19
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Expires: 2001-09-23
Abstract
Abstract A sampling valve useful in liquid chromatography includes a stationary valve member and a valve member movable with respect thereto. The movable valve member includes an axial bore having a cross-section permitting the insertion therethrough of a sample injection needle.
Inventors
- 👤 Rolf Tamm
- 👤 Toma Tomoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:13
CPC Classifications
G; G01; G01N; G01N30/00; G01N30/02; G01N30/04; G01N30/16; G01N30/18; G01N30/20
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
127 words
Method of feeding samples in liquid chromatography, said method comprises the steps of: providing a sample into a dosing loop by means of an injection needle through a sample inlet valve said valve having stationary and movable members in a first position of said valve, changing said sample valve to a second position, thereby connecting, in series, a transport liquid source, said dosing loop and a separating column, and wherein said providing step includes: sucking an air volume into said injection needle prior to sucking-in said sample; inserting said injection needle, through a bore in said movable valve member into a dosing bore of said stationary valve member, retracting said injection needle after the sample has been introduced and prior to said changing-over of said sample valve.
Claim 2
Dependent Claim
127 words
Method of feeding samples in liquid chromatography, said method comprises the steps of: providing a sample into a dosing loop by means of an injection needle through a sample inlet valve said valve having stationary and movable members in a first position of said valve, changing said sample valve to a second position, thereby connecting, in series, a transport liquid source, said dosing loop and a separating column, and wherein said providing step includes: sucking an air volume into said injection needle prior to sucking-in said sample; inserting said injection needle, through a bore in said movable valve member into a dosing bore of said stationary valve member, retracting said injection needle after the sample has been introduced and prior to said changing-over of said sample valve.
Claim 3
Dependent Claim
16 words
Method as claimed in claim 1, wherein an injection needle having a pointed tip is used.
Claim 4
Dependent Claim
81 words
Method as claimed in claim 2, wherein the use of an injection needle which has been made by lateral bending of the end of a capillary and oblique cutting off of this bend end, whereby the injection needle which has been made by lateral bending of the end of a capillary and oblique cutting off of this bend end, whereby the injection needle has a tip substantially omits longitudinal axis and a longitudinal passage deflected at its end and opening laterally.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-07-18 | 1987-01-17 | 1987-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-07-18 | 1991-01-17 | 1991-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-07-18 | 1995-01-17 | 1995-07-19 | $7700.00 | Window Closed / Lapsed |