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US4476734A Expired / Lapsed US ⏱️ 0.0 years remaining

Wet needle sampler for use with a gas chromatograph

Assignee: International Business Machines Corp
•
Filing: 1983-03-07
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Granted: 1984-10-16
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Expires: 2003-03-07
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Abstract

Abstract The flushing of the syringe with a side port is performed by introducing a liquid solvent through the side port while the plunger is retracted from the barrel. At the completion of the flushing operation the plunger is fully inserted into the barrel expelling all the solvent except that in the needle. The needle is then inserted into the sample and the plunger is raised to withdraw the sample. With this arrangement, it is possible to take a 0.1 L sample and dispense it because of the solvent reserve in the barrel. Furthermore, the solvent reserved in the barrel provides a buffer so that sampled material does not contact the plunger or get into the annular space around the retracted plunger.

Inventors

  • 👤 Thomas M. Banks
  • 👤 Raymond R. Ruckel
  • 👤 Samuel F. Spencer
  • 👤 John Q. Walker

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 08:25
CPC Classifications
G; G01; G01N; G01N30/00; G01N30/02; G01N30/04; G01N30/24; G01N35/00; G01N35/10; G01N35/1095

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 146 words
In an automatic sample handler having a syringe with a barrel with a needle at one end and a plunger inserted into the barrel at the other end and also having a port through the body of the barrel, the method of taking samples comprising: (a) pumping a solvent into the port through the barrel and out the needle while the end of the plunger is withdrawn beyond the port so that the syringe is back flushed of contaminants and the barrel filled with solvent, (b) inserting the end of the plunger past the port in the barrel to expel through the needle solvent introduced by step (a), and (c) drawing a liquid sample material up into the barrel through a needle by partially withdrawing the plunger from the barrel after completion of cleaning of the syringe using steps (a) and (b) to take a sample.
Claim 2
Dependent Claim 146 words
In an automatic sample handler having a syringe with a barrel with a needle at one end and a plunger inserted into the barrel at the other end and also having a port through the body of the barrel, the method of taking samples comprising: (a) pumping a solvent into the port through the barrel and out the needle while the end of the plunger is withdrawn beyond the port so that the syringe is back flushed of contaminants and the barrel filled with solvent, (b) inserting the end of the plunger past the port in the barrel to expel through the needle solvent introduced by step (a), and (c) drawing a liquid sample material up into the barrel through a needle by partially withdrawing the plunger from the barrel after completion of cleaning of the syringe using steps (a) and (b) to take a sample.
Claim 3
Dependent Claim 31 words
The method of claim 1 including the additional step (d) of expelling the sample from the syringe into a gas chromatograph through the needle by inserting the plunger into the barrel.
Claim 4
Dependent Claim 18 words
The method of claim 2 including inserting the plunger completely into the barrel during steps (b) and (d).
Claim 5
Dependent Claim 30 words
The method of claim 3 wherein in withdrawing the plunger in step (c) the plunger's movement is sufficient only to draw liquid into the needle and not into the barrel.
Claim 6
Dependent Claim 131 words
In an automatic sample handler having a syringe with a barrel having a needle attached to one end and a plunger inserted into the other end and also having a port through the body of the barrel, apparatus for taking samples comprising: (a) pumping means for forcing solvent through the port into the barrel and out the needle to flush the syringe of contaminants, (b) sampling means for relative positioning of the needle and liquid sample vials for introduction of samples in the vials into syringe through the tip of the needle, and (c) syringe actuation means both for movement of the plunger to withdraw the plunger during flushing of the syringe and the taking of samples and for movement of the barrel during insertion of the needle into sample vials.
Claim 7
Dependent Claim 131 words
In an automatic sample handler having a syringe with a barrel having a needle attached to one end and a plunger inserted into the other end and also having a port through the body of the barrel, apparatus for taking samples comprising: (a) pumping means for forcing solvent through the port into the barrel and out the needle to flush the syringe of contaminants, (b) sampling means for relative positioning of the needle and liquid sample vials for introduction of samples in the vials into syringe through the tip of the needle, and (c) syringe actuation means both for movement of the plunger to withdraw the plunger during flushing of the syringe and the taking of samples and for movement of the barrel during insertion of the needle into sample vials.
Claim 8
Dependent Claim 20 words
The automatic sample handler of claim 5 including waste means for receiving liquid pumped through the syringe during flushing operations.

References Cited (Backward Citations)

US3508442A Cited
US3529475A Cited
US3800984A Cited
US4130394A Cited
US4429583A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-10-16 1988-04-16 1988-10-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-10-16 1992-04-16 1992-10-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-10-16 1996-04-16 1996-10-16 $7700.00 Window Closed / Lapsed

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