ELECTROCHEMICAL CELL

• US 3,655,546 A
• Filed: 04/22/1969
• Issued: 04/11/1972
• Est. Priority Date: 04/22/1969
• Status: Expired due to Term

• Current Assignee: Frank A. Marovich, Ray I. Wilson
• Original Assignee: Frank A. Marovich, Ray I. Wilson
• Inventors: Marovich, Frank A., Wilson, Ray I.
• Primary Examiner(s): Tung, T.
• Application Number:
  US04/818,214
• Time in Patent Office: 1,085 Days
• Field of Search: 204/1T,195
• US Class Current: 204/415
• CPC Class Codes: G01N 27/404 Cells with anode, cathode and cell electrolyte on the same side of a permeable membrane which separates them from the sample fluid , e.g. Clark-type oxygen sensors

Abstract

An electrochemical cell for determining a constituent in a sample in which a pair of electrodes are joined by an electrolyte and separated from the sample by a selectively permeable membrane. A perforated plate overlying the membrane adjacent to the sensing electrode of the cell is spring biased toward said electrode. As a consequence, when the cell is subjected to a vacuum environment, the spring biased perforated plate will prevent alterations in the thickness of the electrolyte film space between the membrane and sensing electrode or bursting of the membrane due to the relatively higher pressure within the cell. The cell is stable in a vacuum environment and has fast response when utilized at low sample gas pressure.

Claims

1. An electrochemical cell for determining a constituent in a sample comprising a pair of electrodes adapted to be joined by an electrolyte, one of said electrodes being a sensing electrode, a membrane permeable to the constituent and impermeable to the electrolyte arranged to separate said electrodes and electrolyte from the sample being analyzed, and said membrane overlying said sensing electrode to define an electrolyte film space therebetween wherein the improvement comprises:

a perforated plate overlying said membrane adjacent to said sensing electrode, said plate comprising a ring provided with a plurality of spaced radially inwardly extending spokes; and

means biasing said plate toward the sensing electrode.

2. A cell as set forth in claim 1 wherein said spokes and the force applied thereto by said biasing means provide sufficient external support for said membrane to withstand about one atmosphere internal cell pressure when the exterior of the cell is exposed to a vacuum environment.

3. A cell as set forth in claim 1 wherein some of said radially inwardly extending spokes terminate short of the center of said ring, and said center overlies said sensing electrode.

4. An electrochemical cell for determining a constituent in a sample comprising a pair of electrodes adapted to be joined by an electrolyte, one of said electrodes being a sensing electrode, a membrane permeable to the constituent and impermeable to the electrolyte arranged to separate said electrodes and electrolyte from the sample being analyzed, and said membrane overlying said sensing electrode to define an electrolyte film space therebetween wherein the improvement comprises:

a circular perforated plate overlying said membrane adjacent to said sensing electrode, said plate being formed with a plurality of radially extending perforations with the center of said plate approximately overlying the center of said sensing electrode; and

means biasing said plate toward said sensing electrode.

5. A cell as set forth in claim 4 wherein said cell includes a nonconductive body positioned in an electrolyte reservoir, said sensing electrode being mounted in said body and terminating at one end thereof, said membrane and plate overlying said one end of said body, a passage in said body extending from the side thereof in communication with said reservoir to said one end of the body and within the outer limits of said radially extending perforations.