Patent US3219432A successfully refreshed from Google Patents.
Patent US4024061A successfully refreshed from Google Patents.
US4024061A
Expired / Lapsed
US
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Pulse dampers for liquid chromatography
Assignee: Pye Electronic Products Ltd
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Filing: 1975-08-26
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Granted: 1977-05-17
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Expires: 1995-08-26
Abstract
Abstract In a liquid chromatograph apparatus, a pulse damper consists of a block of solid material almost filling the cavity of the damper, for example a polytetrafluoroethylene block occupying 99% of the volume of the cavity but arranged to move freely therein.
Inventors
- 👤 John William Gatiss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:46
CPC Classifications
B; B01; B01D; B01D15/00; B01D15/08; B01D15/10; B01D15/16; B01D15/163; G; G01; G01N; G01N30/00; G01N30/02; G01N30/26; G01N30/28; G01N30/32; G01N30/36; G01N2030/322
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
120 words
A liquid chromatograph apparatus comprising a liquid system including a pulse damper, said system being arranged to contain a liquid and having a given total hydraulic capacitance, wherein said pulse damper comprises a chamber having rigid walls and enclosing a cavity having a given volume, means for communication of said liquid with said cavity, and at least one block formed entirely of a solid material and arranged to be immersed in said liquid, said at least one block being arranged in said cavity and occupying a large portion of the volume of the cavity, said solid material having a volume and a bulk elastic modulus such that compressibility of said material provides a major portion of the total hydraulic capacitance.
Claim 2
Dependent Claim
120 words
A liquid chromatograph apparatus comprising a liquid system including a pulse damper, said system being arranged to contain a liquid and having a given total hydraulic capacitance, wherein said pulse damper comprises a chamber having rigid walls and enclosing a cavity having a given volume, means for communication of said liquid with said cavity, and at least one block formed entirely of a solid material and arranged to be immersed in said liquid, said at least one block being arranged in said cavity and occupying a large portion of the volume of the cavity, said solid material having a volume and a bulk elastic modulus such that compressibility of said material provides a major portion of the total hydraulic capacitance.
Claim 3
Dependent Claim
27 words
An apparatus as claimed in claim 1 wherein said pulse damper comprises one solid block only, said block having uniform mechanical properties and construction over all regions.
Claim 4
Dependent Claim
15 words
An apparatus as claimed in claim 2 wherein said block is made of homogeneous material.
Claim 5
Dependent Claim
26 words
An apparatus as claimed in claim 3 wherein said material has a bulk elastic modulus of the same order of magnitude as that of said liquid.
Claim 6
Dependent Claim
12 words
An apparatus as claimed in claim 2 wherein said material is polytetrafluoroethylene.
Claim 7
Dependent Claim
13 words
An apparatus as claimed in claim 1 wherein said proportion is approximately 99%.
Claim 8
Dependent Claim
20 words
An apparatus as claimed in claim 1 wherein said block is arranged to be free to move within the chamber.
Claim 9
Dependent Claim
68 words
An apparatus as claimed in claim 1 wherein said means for communication comprises a first passage through an end wall of the chamber, said chamber additionally comprising a second passage through the chamber wall at an end opposite said first passage, and means for communicating between said second passage and a drain valve, whereby liquid can be passed through the pulse damper from one end to the other.
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) | 1980-05-16 | 1980-11-15 | 1981-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-16 | 1984-11-15 | 1985-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-16 | 1988-11-15 | 1989-05-17 | $7700.00 | Window Closed / Lapsed |