Patent US4485001A successfully refreshed from Google Patents.
US4485001A
Expired / Lapsed
US
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Sterilizable pH electrode and method for producing the same
Assignee: Rosemount Inc
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Filing: 1984-02-21
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Granted: 1984-11-27
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Expires: 2004-02-21
Abstract
Abstract A pH electrode which is capable of withstanding repeated exposures to sterilizing temperatures. An electrode body having a pH sensing member is at least partially filled with a bed of electrochemically inert particles. After an internal reference is inserted into the particle bed, the bed is injected with a quantity of electrolyte which is sufficient to establish continuity between the sensing member and the internal reference, but which is not sufficient to produce destructive internal pressures when the electrode is subjected to sterilizing temperatures. The electrode is completed by forming a seal between the electrode body and the internal reference.
Inventors
- 👤 John N. Harman, III
- 👤 Radhakrishna M. Neti
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:38
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/28; G01N27/30; G01N27/36
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
126 words
A pH electrode which is capable of retaining its pH sensitivity in spite of repeated exposures to sterilizing temperatures, comprising: (a) an electrode body having a pH sensing member and a support member, (b) a bed of electrochemically inert particles packed within the electrode body adjacent to the sensing member, (c) an internal reference at least part of which is embedded in said bed, (d) a quantity of an electrolyte retained within said bed, the quantity of said electrolyte being large enough to establish electrical continuity between the sensing member and the internal reference, but small enough to prevent destructive pressures from arising within said body when the electrode is exposed to sterilizing temperatures, and (e) means for sealing the internal reference to the support member.
Claim 2
Dependent Claim
126 words
A pH electrode which is capable of retaining its pH sensitivity in spite of repeated exposures to sterilizing temperatures, comprising: (a) an electrode body having a pH sensing member and a support member, (b) a bed of electrochemically inert particles packed within the electrode body adjacent to the sensing member, (c) an internal reference at least part of which is embedded in said bed, (d) a quantity of an electrolyte retained within said bed, the quantity of said electrolyte being large enough to establish electrical continuity between the sensing member and the internal reference, but small enough to prevent destructive pressures from arising within said body when the electrode is exposed to sterilizing temperatures, and (e) means for sealing the internal reference to the support member.
Claim 3
Dependent Claim
14 words
The electrode of claim 1 in which said particles are composed primarily of silica.
Claim 4
Dependent Claim
15 words
The electrode of claim 1 in which said particles are composed primarily of hydrated silica.
Claim 5
Dependent Claim
13 words
The electrode of claim 1 in which said particles are composed of glass.
Claim 6
Dependent Claim
24 words
The electrode of claim 1 in which the thermal expansion and contraction of the bed is adapted to track that of the electrode body.
Claim 7
Dependent Claim
18 words
The electrode of claim 1 in which said particles have a maximum size corresponding to approximately 100 mesh.
Claim 8
Dependent Claim
23 words
The electrode of claim 6 in which the quantity of electrolyte is approximately 20 to 100 microliters per cubic centimeter of the bed.
Claim 9
Dependent Claim
31 words
The electrode of claim 1 in which the tendency of the particles to adhere to the sensing member is similar to the tendency of the particles to adhere to one another.
Claim 10
Dependent Claim
28 words
The electrode of claim 1 in which said particles are small enough to produce capillary forces that are sufficient to distribute the electrolyte approximately uniformly throughout the bed.
Claim 11
Dependent Claim
30 words
The electrode of claim 1 in which the support member comprises a length of glass tubing, and in which the sealing means comprises a heat sealed portion of said tubing.
Claim 12
Dependent Claim
35 words
The electrode of claim 1 in which the support member comprises a length of glass tubing, and in which the sealing means comprises an electrochemically inert plug located at one end of the support member.
Claim 13
Dependent Claim
23 words
The electrode of claim 1 in which the bed is compressed into a substantially solid mass prior to the introduction of the electrolyte.
Claim 14
Dependent Claim
142 words
A pH electrode which is capable of retaining its pH sensitivity in spite of repeated exposures to sterilizing temperatures, comprising (a) a glass pH sensing member, (b) an electrically nonconducting support member for supporting and forming a liquid-tight seal with the sensing member, (c) said sensing and support members together defining an electrolyte retaining space, (d) a fluid retaining matrix comprising particles of an electrochemically inert material packed within said space, (e) a conductor having one end embedded in said matrix, (f) means penetrated by the conductor for fluidically sealing said matrix within said space, and (g) a quantity of an electrolyte fluid within said matrix, the quantity of said electrolyte being sufficient to establish fluidic continuity between the sensing member and the conductor, but not sufficient to produce destructive pressures within said space when the electrode is exposed to sterilizing temperatures.
Claim 15
Dependent Claim
142 words
A pH electrode which is capable of retaining its pH sensitivity in spite of repeated exposures to sterilizing temperatures, comprising (a) a glass pH sensing member, (b) an electrically nonconducting support member for supporting and forming a liquid-tight seal with the sensing member, (c) said sensing and support members together defining an electrolyte retaining space, (d) a fluid retaining matrix comprising particles of an electrochemically inert material packed within said space, (e) a conductor having one end embedded in said matrix, (f) means penetrated by the conductor for fluidically sealing said matrix within said space, and (g) a quantity of an electrolyte fluid within said matrix, the quantity of said electrolyte being sufficient to establish fluidic continuity between the sensing member and the conductor, but not sufficient to produce destructive pressures within said space when the electrode is exposed to sterilizing temperatures.
Claim 16
Dependent Claim
14 words
The electrode of claim 13 in which said particles are composed primarily of silica.
Claim 17
Dependent Claim
15 words
The electrode of claim 13 in which the particles are composed primarily of hydrated silica.
Claim 18
Dependent Claim
13 words
The electrode of claim 13 in which said particles are composed of glass.
Claim 19
Dependent Claim
18 words
The electrode of claim 13 in which the particles have a maximum size corresponding to approximately 100 mesh.
Claim 20
Dependent Claim
23 words
The electrode of claim 17 in which the quantity of electrolyte is approximately 20 to 100 microliters per cubic centimeter of said space.
Claim 21
Dependent Claim
31 words
The electrode of claim 13 in which the tendency of the particles to adhere to the sensing member is similar to the tendency of the particles to adhere to one another.
Claim 22
Dependent Claim
28 words
The electrode of claim 13 in which the particles are small enough to produce capillary forces which are sufficient to distribute the electrolyte approximately uniformly throughout said space.
Claim 23
Dependent Claim
28 words
The electrode of claim 13 in which the support member comprises a glass tube, and in which the sealing means comprises a heat sealed portion of said tube.
Claim 24
Dependent Claim
32 words
The electrode of claim 13 in which the support member comprises a glass tube, and in which the sealing means comprises an electrochemically inert plug located at one end of said tube.
Claim 25
Dependent Claim
23 words
The electrode of claim 13 in which the bed is compressed into a substantially solid mass prior to the introduction of the electrolyte.
Claim 26
Independent Claim
131 words
A method for fabricating a pH electrode which is capable of retaining its pH sensitivity in spite of repeated exposures to sterilizing temperatures, said method comprising the steps of: (a) forming a pH electrode body having a pH sensing member and a support member, (b) filling at least the portion of the body which is adjacent to the sensing member with electrochemically inert particles, (c) inserting an electrical conductor into the particles, (d) compressing the particles into a solid bed, (e) introducing into the bed a quantity of electrolyte which is large enough to establish electrical continuity between the sensing member and the conductor, but which is small enough to prevent a pressure-initiated fracture of said body, and (f) forming a fluid tight seal between the conductor and the support member.
Claim 27
Independent Claim
131 words
A method for fabricating a pH electrode which is capable of retaining its pH sensitivity in spite of repeated exposures to sterilizing temperatures, said method comprising the steps of: (a) forming a pH electrode body having a pH sensing member and a support member, (b) filling at least the portion of the body which is adjacent to the sensing member with electrochemically inert particles, (c) inserting an electrical conductor into the particles, (d) compressing the particles into a solid bed, (e) introducing into the bed a quantity of electrolyte which is large enough to establish electrical continuity between the sensing member and the conductor, but which is small enough to prevent a pressure-initiated fracture of said body, and (f) forming a fluid tight seal between the conductor and the support member.
Claim 28
Dependent Claim
14 words
The method of claim 24 in which the particles are composed primarily of silica.
Claim 29
Dependent Claim
15 words
The method of claim 24 in which the particles are composed primarily of hydrated silica.
Claim 30
Dependent Claim
13 words
The method of claim 24 in which the particles are composed of glass.
Claim 31
Dependent Claim
18 words
The method of claim 24 in which the maximum size of the particles corresponds to approximately 100 mesh.
Claim 32
Dependent Claim
26 words
The method of claim 24 in which step (e) includes the introduction of from 20 to 100 microliters of electrolyte per cubic centimeter of the bed.
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) | 1987-11-27 | 1988-05-28 | 1988-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-11-27 | 1992-05-28 | 1992-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-11-27 | 1996-05-28 | 1996-11-27 | $7700.00 | Window Closed / Lapsed |