US4410409A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Amperometric gas sensor, cathode assembly therefor and method of making said cathode assembly
Assignee: Beckman Coulter Inc
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Filing: 1981-12-28
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Granted: 1983-10-18
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Expires: 2001-12-28
Abstract
Abstract An improved electrode assembly for use in amperometric gas sensors. A portion of the interior of the electrode assembly that is adjacent to the electrode is filled with an electrochemically inert water-repellant fluid. Once the fluid is in place, a fluid barrier is inserted to cover the fluid and to serve as a foundation for the introduction of a sealing compound. A pressure relief structure, such as a gas bubble, may be provided within the fluid to relieve the pressures incident to the thermal expansion and contraction of the electrode assembly. Because of the water repellancy of the fluid, the electrolyte solution which surrounds the electrode assembly is prevented from migrating into the interior thereof and thereby initiating output current errors.
Inventors
- 👤 John N. Harman, III
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:33
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/403; G01N27/404; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
114 words
In an electrochemical gas sensor of the type having a gas permeable membrane, a housing defining an electrolyte chamber for receiving an electrolyte solution, an electrode, and an electrode mounting element for mounting the electrode in the electrolyte chamber in the vicinity of the gas permeable membrane, the improvement comprising: (a) a quantity of an electrochemically inert, electrically nonconductive fluid which is immiscible with the electrolyte solution, (b) means for sealing said quantity of fluid, within the electrode mounting element, in direct contact with the inner surface of the electrode, (c) whereby the electrolyte solution is substantially prevented from entering the mounting element and coming into contact with the inner surface of the electrode.
Claim 2
Dependent Claim
114 words
In an electrochemical gas sensor of the type having a gas permeable membrane, a housing defining an electrolyte chamber for receiving an electrolyte solution, an electrode, and an electrode mounting element for mounting the electrode in the electrolyte chamber in the vicinity of the gas permeable membrane, the improvement comprising: (a) a quantity of an electrochemically inert, electrically nonconductive fluid which is immiscible with the electrolyte solution, (b) means for sealing said quantity of fluid, within the electrode mounting element, in direct contact with the inner surface of the electrode, (c) whereby the electrolyte solution is substantially prevented from entering the mounting element and coming into contact with the inner surface of the electrode.
Claim 3
Dependent Claim
28 words
A gas sensor as set forth in claim 1 in which the inert fluid is selected from the group consisting of silicone oils, fluorinated oils and mineral oils.
Claim 4
Dependent Claim
30 words
A gas sensor as set forth in claim 1 including pressure-relief means for protecting the electrode from the pressures incident to the thermal expansion and contraction of the gas sensor.
Claim 5
Dependent Claim
43 words
A gas sensor as set forth in claim 1 in which the sealing means includes a fluid barrier for confining the fluid to the electrode end of the mounting element, and a potting compound for sealing the fluid barrier to the mounting element.
Claim 6
Dependent Claim
124 words
An electrode assembly for use in electrochemical gas sensors of the type having a gas permeable membrane and an electrolyte chamber containing an electrolyte solution, said electrode assembly being characterized by: (a) an electrode, (b) an electrode mounting element for supporting the electrode in the electrolyte chamber in the vicinity of the membrane, (c) a conductor within the mounting element for connecting the electrode in a remote measuring circuit, (d) an electrochemically inert, electrically insulating water repellant fluid, (e) means for sealing a body of said fluid within the electrode mounting element in direct contact with the inner surface of the electrode, (f) whereby said fluid covers the inner surface of the electrode and prevents the electrolyte solution from entering the electrode mounting element.
Claim 7
Dependent Claim
124 words
An electrode assembly for use in electrochemical gas sensors of the type having a gas permeable membrane and an electrolyte chamber containing an electrolyte solution, said electrode assembly being characterized by: (a) an electrode, (b) an electrode mounting element for supporting the electrode in the electrolyte chamber in the vicinity of the membrane, (c) a conductor within the mounting element for connecting the electrode in a remote measuring circuit, (d) an electrochemically inert, electrically insulating water repellant fluid, (e) means for sealing a body of said fluid within the electrode mounting element in direct contact with the inner surface of the electrode, (f) whereby said fluid covers the inner surface of the electrode and prevents the electrolyte solution from entering the electrode mounting element.
Claim 8
Dependent Claim
19 words
An electrode assembly as set forth in claim 5 in which said inert fluid contains a di-methyl siloxane polymer.
Claim 9
Dependent Claim
18 words
An electrode assembly as set forth in claim 5 in which said inert fluid contains a fluorinated oil.
Claim 10
Dependent Claim
17 words
An electrode assembly as set forth in claim 5 in which said inert fluid contains mineral oil.
Claim 11
Dependent Claim
30 words
A cathode assembly as set forth in claim 5 including pressure-relief means for protecting the electrode from the pressures incident to the thermal expansion and contraction of the electrode assembly.
Claim 12
Independent Claim
154 words
A method for forming an electrode assembly for use in an electrochemical gas sensor of the type having a gas permeable membrane, an electrolyte chamber, and an electrode, said method including the steps of: (a) producing an electrode mounting element having an axial opening, (b) attaching a conductor to one side of the electrode, (c) glueing the electrode on one end of the mounting element to form a substantially fluid tight seal therewith, said conductor projecting into the axial opening of the mounting element, (d) injecting an electrochemically inert water repellant fluid into the axial opening to form a layer of fluid covering the inner surface of the electrode and the attached end of the conductor, (e) inserting a fluid barrier into the axial opening to cover said fluid layer, and (f) injecting a sealing compound into the axial opening to cover the fluid barrier and thereby seal the interior of the electrode assembly.
Claim 13
Independent Claim
154 words
A method for forming an electrode assembly for use in an electrochemical gas sensor of the type having a gas permeable membrane, an electrolyte chamber, and an electrode, said method including the steps of: (a) producing an electrode mounting element having an axial opening, (b) attaching a conductor to one side of the electrode, (c) glueing the electrode on one end of the mounting element to form a substantially fluid tight seal therewith, said conductor projecting into the axial opening of the mounting element, (d) injecting an electrochemically inert water repellant fluid into the axial opening to form a layer of fluid covering the inner surface of the electrode and the attached end of the conductor, (e) inserting a fluid barrier into the axial opening to cover said fluid layer, and (f) injecting a sealing compound into the axial opening to cover the fluid barrier and thereby seal the interior of the electrode assembly.
Claim 14
Dependent Claim
22 words
The method of claim 10 in which the inert fluid contains one or more of silicone oils, fluorinated oils, and mineral oils.
Claim 15
Dependent Claim
25 words
The method of claim 10 further including the step of introducing pressure-relief means into said layer of fluid before the insertion of the fluid barrier.
References Cited (Backward Citations)
US3518179A
Cited
US4268370A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-10-17 | 1987-04-18 | 1987-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-17 | 1991-04-18 | 1991-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-17 | 1995-04-18 | 1995-10-18 | $7700.00 | Window Closed / Lapsed |