US4495039A
Expired / Lapsed
US
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Method for activating a pyrocarbon electrode tip
Assignee: Sorin Biomedica Cardio SpA
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Filing: 1982-08-06
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Granted: 1985-01-22
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Expires: 2002-08-06
Abstract
Abstract A pyrocarbon tip for a cardiac stimulator electrode is subjected to an anodic electrolytic treatment in which a strong, concentrated acid with oxidizing properties, or a mixture of two or more such acids, is used as the electrolyte. The treatment is carried out with a voltage greater than 1 V, preferably between 1 and 20 V, and with a current density greater than 3 mA/mm 2 , preferably between 30 and 40 mA/mm 2 . Pyrocarbon tips treated in this manner have very low bias voltages in use.
Inventors
- 👤 Osvaldo Cerise
- 👤 Pietro Arru
- 👤 Franco Vallana
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:52
CPC Classifications
A; A61; A61N; A61N1/00; A61N1/02; A61N1/04; A61N1/05
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
77 words
Method for activating a pyrocarbon tip for an electrode for a cardiac stimulator, consisting of subjecting the tip to an anodic electrolytic treatment in an electrolyte composed of a mixture of 50 parts by weight of concentrated sulphuric acid (98% by weight) and 50 parts by weight of concentrated nitric acid (65% by weight), said electrolytic treatment being carried out with a voltage greater than 1 V and a current density greater than 3 mA/mm 2 .
Claim 2
Dependent Claim
77 words
Method for activating a pyrocarbon tip for an electrode for a cardiac stimulator, consisting of subjecting the tip to an anodic electrolytic treatment in an electrolyte composed of a mixture of 50 parts by weight of concentrated sulphuric acid (98% by weight) and 50 parts by weight of concentrated nitric acid (65% by weight), said electrolytic treatment being carried out with a voltage greater than 1 V and a current density greater than 3 mA/mm 2 .
Claim 3
Dependent Claim
27 words
Method as claimed in claim 1, wherein said voltage is between 2 and 20 V and said current density is between 3 and 40 mA/mm 2 .
Claim 4
Dependent Claim
22 words
Method as claimed in claim 1, wherein said electrolytic treatment is carried out for a period of between 5 and 45 seconds.
Claim 5
Dependent Claim
28 words
Method as claimed in claim 1, wherein said electrolyte is selected from the group consisting of nitric acid, sulphuric acid, percholoric acid and phosphoric acid and their mixtures.
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) | 1988-01-22 | 1988-07-23 | 1989-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-01-22 | 1992-07-23 | 1993-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-01-22 | 1996-07-23 | 1997-01-22 | $7700.00 | Window Closed / Lapsed |