Gas sensor

• US 5,719,325 A
• Filed: 12/16/1996
• Issued: 02/17/1998
• Est. Priority Date: 12/16/1995
• Status: Expired due to Fees

• Current Assignee: Dragerwerk AG
• Original Assignee: Dragerwerk AG
• Inventors: Kiesele, Herbert, Dietrich, Michael
• Primary Examiner(s): Williams, Hezron E.
• Assistant Examiner(s): WIGGINS, JOHN DAVID
• Application Number:
  US08/767,069
• Time in Patent Office: 428 Days
• Field of Search: 73/31.06, 204/431-432, 204/412, 204/406, 204/424, 422/98, 422/90
• US Class Current: 73/31.06
• 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
• CPC Class Codes: G01N 27/4045 for gases other than oxygen

Abstract

A gas sensor has at least a measuring electrode and a counter electrode on an electrolyte layer. This gas sensor is improved with respect to the complete extent of the electrochemical reaction achieved of the gas molecules, which are to be detected, at the measuring electrode by the manner of determining an electrical charge developed or accumulated thereat. To solve this task, the invention provides that the measuring electrode (14) has component electrodes (14a, 14b) which enclose the electrolyte layer (11, 12) in the manner of a sandwich.

Claims

1. A gas sensor for measuring a gas, the gas sensor comprising:

a measuring electrode permeable to said gas to be measured;

said measuring electrode having structure defining first and second individual surfaces which can be subjected to the gas;

said individual surfaces being mutually adjacent and defining a space therebetween;

counter electrode means;

electrolyte means interconnecting said counter electrode and said measuring electrode and at least a portion of said electrolyte means being disposed in said space;

said structure being a conductive porous body defining said individual surfaces; and

,

said electrolyte means including an electrolyte impregnated in said porous body.

2. The gas sensor of claim 1, said body being a sinter metal body.

3. The gas sensor of claim 1, said body being made of a material selected from the group consisting of metal foam and porous carbon.

4. A gas sensor for measuring a gas, the gas sensor comprising:

a measuring electrode permeable to said gas and having first and second gas permeable component measuring electrodes defining respective surfaces which can be subjected to the gas;

counter electrode means;

said component measuring electrodes being mutually adjacent so as to define a space therebetween;

electrolyte means disposed in said space and interconnecting said counter electrode means and said measuring electrode;

said component measuring electrodes and said electrolyte means conjointly defining a sandwich-like structure;

said measuring electrodes being a first measuring electrode and said space being a first space;

a second measuring electrode having first and second ancillary measuring electrodes conjointly defining a second space therebetween; and

,

said electrolyte means extending into said second space whereby said ancillary measuring electrodes and said electrolyte means also define a sandwich-like structure.

5. The gas sensor of claim 4, said counter electrode means including a counter electrode having first and second component counter electrodes conjointly defining a third space therebetween;

and, said electrolyte means also extending into said third space whereby said component counter electrodes and said electrolyte means also define a sandwich-like structure.

6. The gas sensor of claim 5, further comprising a reference electrode including first and second component reference electrodes conjointly defining a fourth space therebetween;

and, said electrolyte means also extending into said fourth space whereby said component reference electrodes and said electrolyte means also conjointly define a sandwich-like structure.

7. The gas sensor of claim 6, further comprising a membrane permeable to said gas and foil-like enclosing said electrolyte means;

and, said component measuring electrodes, said ancillary measuring electrodes, said component counter electrodes and said component reference electrodes all being arranged on said membrane.

8. The gas sensor of claim 7, said electrolyte means including a nonwoven fabric and a liquid electrolyte impregnated in said nonwoven fabric.

9. The gas sensor of claim 7, said electrolyte means being configured as a gel electrolyte layer.

10. The gas sensor of claim 4, said component measuring electrodes being mutually parallel.

11. A gas sensor for measuring a gas, the gas sensor comprising:

a measuring electrode permeable to said gas and having first and second gas permeable component measuring electrodes defining respective surfaces which can be subjected to the gas;

said component measuring electrodes being mutually adjacent so as to define a space therebetween;

counter electrode means;

said counter electrode means having first and second component counter electrodes conjointly defining a space therebetween;

electrolyte means disposed in said spaces and interconnecting said component measuring electrodes and said component counter electrodes; and

,

said component measuring electrodes, said component counter electrodes and said electrolyte means conjointly defining a sandwich-like structure.

12. The gas sensor of claim 11, further comprising a reference electrode including first and second component reference electrodes conjointly defining a space therebetween;

and, said electrolyte means also extending into said space between said reference electrodes.