Electrochemical gage for measuring partial pressures of oxygen

Claim 2

In an electrochemical gage for measuring partial pressures of oxygen, said gage comprising a solid electrolyte and an internal reference, the improvement whereby the internal reference consists essentially of a palladium:palladium oxide redox couple.

Claim 3

An electrochemical oxygen gage, said gage including an internal reference compartment with a hermetic seal, said compartment being substantially filled with an internal reference consisting of solid material selected from the class consisting of palladium, palladium oxide and mixtures thereof, said compartment being defined at least in part by a solid electrolyte, and at least one electronic conductor leading into said compartment and electronically connected within said compartment both with the reference material and said electrolyte.

Claim 4

An electrochemical oxygen gage, said gage including an internal reference compartment with a hermetic seal, said compartment being substantially filled with an internal reference consisting of solid material selected from the class consisting of palladium, palladium oxide and mixtures thereof, said compartment being defined at least in part by a solid electrolyte, and at least one electronic conductor leading into said compartment and electronically connected within said compartment both with the reference material and said electrolyte.

Claim 5

A gage according to claim 2 wherein said compartment is sealed at the point where said conductor enters.

Claim 6

A gage according to claim 2 wherein said compartment is in the shape of a sheath which is closed at one end and which is formed of said solid electrolyte.

Claim 7

A gage according to claim 4 wherein said sheath is sealed around said conductor at the end of the sheath opposite to the said one end.

Claim 8

A gage according to claim 2 including a thermocouple mounted inside said compartment.

Claim 9

A gage according to claim 6 wherein said thermocouple has a pair of limbs at least one of which constitutes at least a part of said conductor.

Claim 10

A gage according to claim 6 wherein said thermocouple has a pair of limbs and said electronic conductor is constituted by one of said limbs, the other limb being in electronic contact with the interior surface of the electrolyte.

Claim 11

A gage according to claim 2 including an exterior electronic conductor attached in electronic contact with the exterior surface of said electrolyte.

Claim 12

The gage of claim 9, wherein the exterior conductor is positioned in a groove in the exterior surface of the electrolyte.

Claim 13

The gage of claim 9, wherein the one electronic conductor has a generally serpentine shape and touches the interior surface of the compartment at the peaks.

Claim 14

The gage of claim 11, wherein alternate peaks of the conductor touch opposite surfaces of the compartment.

Claim 15

The gage of claim 2, wherein the compartment is not more than about 12 mm long and has an exterior diameter of not more than about 2 mm.

Claim 16

The gage of claim 13 having an internal reference compartment volume of no more than about 10 mm 3 .

Claim 17

The gage of claim 13 having an external diameter of the order of 1 mm.

Claim 18

The gage of claim 2, in combination with means for supplying current to the gage to produce transfer of oxygen through the solid electrolyte in a direction to regenerate the reference material within the compartment.

Claim 19

An oxygen gage comprising a sheath which is closed at one end and which is formed of solid electrolyte, said sheath having interior and exterior surfaces, an internal reference material within said sheath, said material consisting essentially of palladium and palladium oxide in intimate association, a thermocouple including a pair of leads within said internal reference material, and making electrical contact with said reference material and said interior surface of said sheath, at least one of said leads constituting an internal electrode, said sheath being hermetically sealed around said leads and an exterior electrode attached in electrically conductive contact with the exterior surface of said electrolyte.

Claim 20

An oxygen gage comprising a sheath which is closed at one end and which is formed of solid electrolyte, said sheath having interior and exterior surfaces, an internal reference material within said sheath, said material consisting essentially of palladium and palladium oxide in intimate association, a thermocouple including a pair of leads within said internal reference material, and making electrical contact with said reference material and said interior surface of said sheath, at least one of said leads constituting an internal electrode, said sheath being hermetically sealed around said leads and an exterior electrode attached in electrically conductive contact with the exterior surface of said electrolyte.

Claim 25

An electrochemical gage for measuring the partial pressure of oxygen in a medium, which comprises: a solid oxide electrolyte having ionic conduction and forming at least part of the walls of a compartment; a chemical system within said compartment effective for providing a reference pressure of oxygen at a determined temperature; an inner electronic conductor electrode in contact with said solid electrolyte within said compartment, an outer electronic conductor electrode outside said compartment for providing electric contact to said outside, both said electrochemical gage and said outer electronic conductor being adapted to be brought in contact at an operative temperature with the medium containing the oxygen under partial pressure to be measured; and said chemical system consisting essentially of a palladium: palladium oxide redox couple.

Claim 26

An electrochemical gage for measuring the partial pressure of oxygen in a medium, which comprises: a solid oxide electrolyte having ionic conduction and forming at least part of the walls of a compartment; a chemical system within said compartment effective for providing a reference pressure of oxygen at a determined temperature; an inner electronic conductor electrode in contact with said solid electrolyte within said compartment, an outer electronic conductor electrode outside said compartment for providing electric contact to said outside, both said electrochemical gage and said outer electronic conductor being adapted to be brought in contact at an operative temperature with the medium containing the oxygen under partial pressure to be measured; and said chemical system consisting essentially of a palladium: palladium oxide redox couple.

Claim 27

An electrochemical gage according to claim 20, wherein said compartment has a hermetic seal and wherein said inner electronic conductor electrode is formed of a conductor in electronic contact both with the chemical system and said solid electrolyte, said inner electronic conductor electrode passing through the seal of said compartment.

Claim 28

An electrochemical gage according to claim 15 wherein said chemical system substantially fills the interior of said compartment.

Claim 29

An electrochemical gage for measuring the partial pressure of oxygen in a medium, said gage comprising: a solid oxide electrolyte having ionic conduction and forming at least part of the walls of a compartment, a solid chemical system substantially filling said compartment, said system being responsive to the application of predetermined electrical energy to form a redox-mixture of a metal and an oxide of the same metal providing a reference pressure of oxygen at a determined temperature, an inner electronic conductor electrode in contact with said solid electrolyte within said compartment, an outer electronic conductor electrode outside said compartment for providing electric contact to said outside, both said electrochemical gage and said outer electronic conductor being adapted to be brought in contact at an operative temperature with the medium containing the oxygen under partial pressure to be measured, and said solid chemical system being formed of palladium, palladium oxide, or a mixture thereof.

Claim 30

An electrochemical gage for measuring the partial pressure of oxygen in a medium, said gage comprising: a solid oxide electrolyte having ionic conduction and forming at least part of the walls of a compartment, a solid chemical system substantially filling said compartment, said system being responsive to the application of predetermined electrical energy to form a redox-mixture of a metal and an oxide of the same metal providing a reference pressure of oxygen at a determined temperature, an inner electronic conductor electrode in contact with said solid electrolyte within said compartment, an outer electronic conductor electrode outside said compartment for providing electric contact to said outside, both said electrochemical gage and said outer electronic conductor being adapted to be brought in contact at an operative temperature with the medium containing the oxygen under partial pressure to be measured, and said solid chemical system being formed of palladium, palladium oxide, or a mixture thereof.