Patent US5028328A successfully refreshed from Google Patents.
US5028328A
Expired / Lapsed
US
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Controlled pore size coffee filter
Assignee: Individual
•
Filing: 1989-11-30
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Granted: 1991-07-02
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Expires: 2009-11-30
Abstract
Abstract A washable coffee filter using a plastic membrane with a multiplicity of openings with a maximum diameter of less-than-20-microns for making a clear beverage by hot water extraction of finely ground coffee beans.
Inventors
- 👤 Joseph F. Long
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:51
CPC Classifications
A; A47; A47J; A47J31/00; A47J31/44; A47J31/4403; A47J31/446
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
59 words
A controlled pore size coffee filter comprising: a) an open cup means with support means to hold said open cup means in the top of an open coffee pot; b) a membrane filter means in the bottom of said open cup means with said membrane filter means having a multiplicity of openings with a maximum diameter of less-than-20- microns.
Claim 2
Dependent Claim
59 words
A controlled pore size coffee filter comprising: a) an open cup means with support means to hold said open cup means in the top of an open coffee pot; b) a membrane filter means in the bottom of said open cup means with said membrane filter means having a multiplicity of openings with a maximum diameter of less-than-20- microns.
Claim 3
Dependent Claim
24 words
A controlled pore size coffee filter as in claim 1 wherein said membrane filter means snaps into a bottom of said open cup means.
Claim 4
Dependent Claim
48 words
A controlled pore size coffee filter as in claim 2 wherein said membrane filter means comprises a stainless support grid attached to a solid outer ring with a plastic membrane having a multiplicity of openings with a maximum diameter of less-than-20 microns fused to said stainless support grid.
Claim 5
Dependent Claim
48 words
A controlled pore size coffee filter as in claim 2 wherein said membrane filter means comprises a plastic support grid attached to a solid outer ring with a plastic membrane having a multiplicity of openings with a maximum diameter of less-than-20 microns fused to said plastic support grid.
Claim 6
Dependent Claim
43 words
A controlled pore size coffee filter as in claim 1 wherein said membrane filter means is a plastic supported membrane with a multiplicity of openings with a maximum diameter of less-than-20 microns and is sealed in the bottom of said open cup means.
Claim 7
Dependent Claim
19 words
A controlled pore size coffee filter as in claim 5 where said plastic supported membrane is a fluorocarbon polymer.
Claim 8
Dependent Claim
43 words
A controlled pore size coffee filter as in claim 1 wherein said membrane filter means is a plastic membrane having a multiplicity of openings with a maximum diameter of less-than-20 microns and is adhering to the top surface of an open support grid.
Claim 9
Dependent Claim
77 words
A controlled pore size coffee filter comprising: a) an open cup means with support means to hold said open cup means in the top of an open coffee pot; b) a membrane filter means in the bottom of said open cup means with uniform pore size openings with a maximum diameter of less-than-20 microns to permit gravity flow of a minimum of 100 ml. per minute when said membrane filter means is approximately four inches in diameter.
Claim 10
Dependent Claim
77 words
A controlled pore size coffee filter comprising: a) an open cup means with support means to hold said open cup means in the top of an open coffee pot; b) a membrane filter means in the bottom of said open cup means with uniform pore size openings with a maximum diameter of less-than-20 microns to permit gravity flow of a minimum of 100 ml. per minute when said membrane filter means is approximately four inches in diameter.
References Cited (Backward Citations)
US3935112A
Cited
US3943058A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-07-01 | 1994-12-31 | 1995-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-01 | 1998-12-31 | 1999-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-01 | 2002-12-31 | 2003-07-02 | $7700.00 | Window Closed / Lapsed |