US4852581A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure transducer with conductive polymer bridge
Assignee: Smiths Medical ASD Inc
•
Filing: 1987-12-14
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Granted: 1989-08-01
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Expires: 2007-12-14
Abstract
Abstract A pressure transducer has a thin central portion formed of a molded thermoplastic resin. A conductive polymer forms the resistive elements of a Wheatstone bridge printed and baked onto the molded substrate.
Inventors
- 👤 Thomas P. Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:57
CPC Classifications
G; G01; G01L; G01L9/00; G01L9/0041; G01L9/0051; G01L9/0052; G01L9/0055; G01L1/00; G01L1/20; G01L1/22; G01L1/2287
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
36 words
A pressure transducer comprising: a molded high temperature, thermoplastic substrate having a thin flexible section, at least one conductive polymer resistor printed on said flexible section, said resistor changing its resistance when said substrate is flexed.
Claim 2
Dependent Claim
36 words
A pressure transducer comprising: a molded high temperature, thermoplastic substrate having a thin flexible section, at least one conductive polymer resistor printed on said flexible section, said resistor changing its resistance when said substrate is flexed.
Claim 3
Dependent Claim
53 words
A pressure transducer comprising: a molded substrate formed from a high temperature thermoplastic material having a thick border and a thin flexible central section, a resistance bridge formed of conductive polymer resistors printed and baked on said thin central section, said resistors having ends, and conductors connected to the ends of said resistors.
Claim 4
Dependent Claim
53 words
A pressure transducer comprising: a molded substrate formed from a high temperature thermoplastic material having a thick border and a thin flexible central section, a resistance bridge formed of conductive polymer resistors printed and baked on said thin central section, said resistors having ends, and conductors connected to the ends of said resistors.
Claim 5
Dependent Claim
26 words
A transducer as in claim 2 in which said conductors are printed on said substrate and leads are connected to said conductors with a conductive epoxy.
Claim 6
Dependent Claim
13 words
A transducer as in claim 2 in which said thick border is circular.
Claim 7
Dependent Claim
29 words
A transducer as in claim 2 in which said thick border is circular and the center of said central section has a thick integrally-molded boss forming a rigid center.
Claim 8
Dependent Claim
24 words
A transducer as in claim 2 in which said thin central section has a thickness in the range of about 5 to 15 mils.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-31 | 1993-01-30 | 1993-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-31 | 1997-01-30 | 1997-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-31 | 2001-01-30 | 2001-08-01 | $7700.00 | Window Closed / Lapsed |