Patent US1981600A successfully refreshed from Google Patents.
Patent US3572648A successfully refreshed from Google Patents.
US3572648A
Expired / Lapsed
US
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Pharmeceutical testing instrument
Assignee: WILLIAM A HANSON
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Filing: 1969-06-13
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Granted: 1971-03-30
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Expires: 1989-06-13
Abstract
Abstract A basket stirrer for testing the dissolution rate of solid pharmaceutical preparations such as tablets and capsules. Passage means is provided through the drive plug which forms a closure at the upper end of the generally cylindrical screen basket to break the air or fluid lock which otherwise introduces errors in the routine laboratory use of this type of equipment by preventing proper fluid drainage from the basket when it is raised out of the testing solution at the end of a test, or proper circulation of the fluid through the basket during the test.
Inventors
- 👤 William A Hanson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:10
CPC Classifications
G; G01; G01N; G01N13/00; G01N2013/006; G01N35/00; G01N2035/00178; G01N2035/00188; G01N2035/00198; G01N33/00; G01N33/15
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
41 words
A pharmaceutical testing instrument as defined in claim 1, wherein said passage means includes at least one passage having a minimum cross-sectional area at least as great as that of a circular passage having a diameter of about 1 1/2 millimeters.
Claim 2
Dependent Claim
35 words
A pharmaceutical testing instrument as defined in claim 2, wherein said passage means includes no passage having a minimum cross-sectional area greater than that of a circular passage having a diameter of about 4 millimeters.
Claim 3
Dependent Claim
62 words
A pharmaceutical testing instrument as defined in claim 1, wherein said passage means includes at least one passage having a minimum cross-sectional area at least as great as that of a circular passage having a diameter of about 2 millimeters, but no passage having a minimum cross-sectional area greater than that of a circular passage having a diameter of about 3 millimeters.
Claim 4
Dependent Claim
31 words
A pharmaceuticAl testing instrument as defined in claim 3, wherein said passage means is substantially straight and oriented substantially parallel to the axis of the drive shaft, drive plug and basket.
Claim 5
Dependent Claim
29 words
A pharmaceutical testing instrument as defined in claim 5, wherein said basket includes a generally cylindrical screen sidewall, and said passage means is offset substantially radially inwardly relative thereto.
Claim 6
Dependent Claim
23 words
A pharmaceutical testing instrument as defined in claim 6, wherein said passage means comprises a single passage having a substantially circular cross section.
Claim 7
Dependent Claim
22 words
A pharmaceutical testing instrument as defined in claim 3, wherein said passage means comprises a peripherally located notch in said drive plug.
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) | 1974-03-29 | 1974-09-28 | 1975-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-29 | 1978-09-28 | 1979-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-29 | 1982-09-28 | 1983-03-30 | $7700.00 | Window Closed / Lapsed |