Oxygen sensor based on a metal-air battery
First Claim
Patent Images
1. A sensor for measuring oxygen concentration comprising:
- a metal-air cell which generates an electric current when exposed to oxygen comprising a casing having at least one port therein for admission of oxygen to serve as a cathode, a metal anode and first and second terminal means for making electrical contact with said anode and cathode, respectively;
electrical circuit means connected to said terminal means providing a variable resistive load across said terminal means, the resistive load increasing under conditions of low current output from the cell so as to reduce hydrogen evolution at the cathode, andmeans for measuring the current through the cell which is proportional to oxygen concentration.
1 Assignment
0 Petitions
Accused Products
Abstract
An oxygen sensor based on a metal-air cell, typically a commercially available zinc-air battery of the type used in hearing aids. The cell, which admits oxygen to generate electric current at its cathode is disposed in a mechanical housing which restricts the flow of oxygen to the cell, and is connected to an electrical circuit which provides a variable resistance load, the load increasing as current flow through the circuit decreases, to prevent hydrogen evolution at the cathode. Current flow through the cell is measured, and is proportional to oxygen concentration.
-
Citations
20 Claims
-
1. A sensor for measuring oxygen concentration comprising:
-
a metal-air cell which generates an electric current when exposed to oxygen comprising a casing having at least one port therein for admission of oxygen to serve as a cathode, a metal anode and first and second terminal means for making electrical contact with said anode and cathode, respectively; electrical circuit means connected to said terminal means providing a variable resistive load across said terminal means, the resistive load increasing under conditions of low current output from the cell so as to reduce hydrogen evolution at the cathode, and means for measuring the current through the cell which is proportional to oxygen concentration. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. An apparatus for oxygen measurement, comprising:
-
a mechanical housing having a recess therein adapted for receiving a metal-air cell having a port therein for admission of oxygen to serve as a cathode, a metal anode and terminal means for contacting the anode and the cathode, means for restricting diffusion of oxygen from an atmosphere being measured to the port of the metal-air cell, a means for making electrical connection with the terminal means of the metal-air cell, and electrical circuit means connected to said terminal means, said electrical circuit means providing a variable resistance load across said terminal means, with the resistance load across said terminal means increasing when current flow through the electrical circuit means decreases. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19, 20)
-
Specification