US4440550A
Expired / Lapsed
US
⏱️ 0.0 years remaining
On-column injector
Assignee: FISONS US Inc
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Filing: 1983-06-28
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Granted: 1984-04-03
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Expires: 2003-06-28
Abstract
Abstract An apparatus and method for injecting samples into capillary-type gas chromatographic columns allows a portion of the column to be withdrawn from the chromatograph oven prior to injection. The sample is injected into the withdrawn portion of the column which is then inserted back into the oven to initiate volatilization. The apparatus includes a syringe holder which is attached to the inlet end of the column and a collapsible support mechanism for extending the syringe holder away from the chromatograph oven. The sample is injected into the column while the support is extended away from the oven. After the injection is completed, the support is collapsed causing the portion of the column carrying the sample to be abruptly introduced into the oven.
Inventors
- 👤 Rand G. Jenkins
- 👤 Norman W. Wohlers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 05:53
CPC Classifications
G; G01; G01N; G01N30/00; G01N30/02; G01N30/04; G01N30/16; G01N30/18; G01N2030/167
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
122 words
An injector for receiving a sample from a syringe needle and introducing said sample into a capillary column in an oven of a gas chromatograph, said injector comprising: a syringe holder having a central bore for receiving the syringe needle; means located at one end of the central bore for fastening an inlet end of the capillary tube; means located at the other end of the central bore for sealing the central bore when the syringe needle is not therein; and means for supporting the syringe holder relative to the gas chromatograph, said supporting means being collapsible so that the distance between the syringe and the oven can be abruptly varied to withdraw a portion of the capillary column from the oven.
Claim 2
Dependent Claim
122 words
An injector for receiving a sample from a syringe needle and introducing said sample into a capillary column in an oven of a gas chromatograph, said injector comprising: a syringe holder having a central bore for receiving the syringe needle; means located at one end of the central bore for fastening an inlet end of the capillary tube; means located at the other end of the central bore for sealing the central bore when the syringe needle is not therein; and means for supporting the syringe holder relative to the gas chromatograph, said supporting means being collapsible so that the distance between the syringe and the oven can be abruptly varied to withdraw a portion of the capillary column from the oven.
Claim 3
Dependent Claim
30 words
An injector as in claim 1, wherein the supporting means comprises a baseplate fixed to the chromatograph oven and a telescopic column extending between the baseplate and the syringe holder.
Claim 4
Dependent Claim
54 words
An injector as in claim 1, wherein the syringe holder includes an inlet port communicating with the central bore for introducing a carrier gas into the capillary column and a purge port communicating with the central bore for bleeding at least a portion of the carrier gas before it can enter the capillary column.
Claim 5
Dependent Claim
14 words
An injector as in claim 1, wherein the sealing means is a stop cock.
Claim 6
Dependent Claim
81 words
An on-column injector for a gas chromatographic system having an oven and a capillary column within the oven, wherein the injector includes means for receiving a syringe needle and guiding the needle to an inlet end of said capillary column, said injector characterized by means for collapsibly mounting the injector so that said inlet end may be removed from the oven during injection of a sample from the syringe needle and inserted into the oven after the sample injection is completed.
Claim 7
Dependent Claim
81 words
An on-column injector for a gas chromatographic system having an oven and a capillary column within the oven, wherein the injector includes means for receiving a syringe needle and guiding the needle to an inlet end of said capillary column, said injector characterized by means for collapsibly mounting the injector so that said inlet end may be removed from the oven during injection of a sample from the syringe needle and inserted into the oven after the sample injection is completed.
Claim 8
Dependent Claim
20 words
An on-column injector as in claim 5, wherein the means for collapsibly mounting the injector comprises a telescopic column support.
Claim 9
Independent Claim
62 words
A method for introducing a sample into a capillary column located within the oven of a gas chromatograph, said method comprising: maintaining an initial portion of the column outside of the oven; continuously flowing a carrier gas through the column; injecting the sample into the initial portion of the column; and abruptly inserting the intitial portion of the column into the oven.
Claim 10
Independent Claim
62 words
A method for introducing a sample into a capillary column located within the oven of a gas chromatograph, said method comprising: maintaining an initial portion of the column outside of the oven; continuously flowing a carrier gas through the column; injecting the sample into the initial portion of the column; and abruptly inserting the intitial portion of the column into the oven.
Claim 11
Dependent Claim
31 words
A method as in claim 7, wherein the sample volume is less than 1 μl and the sample is injected into the column over a period of less than 1 second.
Claim 12
Dependent Claim
36 words
A method as in claim 7, wherein the sample volume is in the range from 1 to 2 μl and the sample is injected into the column over a period of from 1 to 5 seconds.
Claim 13
Dependent Claim
31 words
A method as in claim 7, wherein the sample volume is over 2 μl and the sample is injected into the column over a period of from 5 to 10 seconds.
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) | 1987-04-03 | 1987-10-03 | 1988-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-04-03 | 1991-10-03 | 1992-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-04-03 | 1995-10-03 | 1996-04-03 | $7700.00 | Window Closed / Lapsed |