Gas sensing electrode system employing hydrophilic wick

Claim 2

An electro-chemical gas detection system, comprising: a housing defining a chamber, a body of a liquid electrolyte carried by said housing within the chamber defined thereby, an elongated reference electrode rod in said housing and being partially immersed in said liquid electrolyte body but having at least one end thereof disposed outwardly of said liquid electrolyte body, an elongated non-porous sensing electrode rod in said housing in spaced relation to said reference electrode rod and being partially immersed in said liquid electrolyte body but having both ends thereof disposed outwardly of said liquid electrolyte body, one end surface of said non-porous sensing electrode rod comprising a sensing surface to which gas to be monitored is adapted to be exposed, meter means electrically connected between said at least one end of said reference electrode rod and the end of said non-porous sensing electrode rod opposite from the end thereof on which said sensing surface is provided, and an elongated hydrophilic porous fiber wick extending transversely across said sensing surface of said non-porous sensing electrode rod and into partial immersion with said liquid electrolyte body for providing a small quantity of the liquid electrolyte across said sensing surface through capillary attraction and absorption by said porous fiber wick of the liquid electrolyte to complete an ohmic connection, said porous fiber wick having a relatively small diametral dimension as compared to the width of said sensing surface and covering only a minor portion of the area of said sensing surface.

Claim 3

AN ELECTRO-CHEMICAL GAS DETECTION SYSTEM, COMPRISING: A HOUSING DEFINING A CHAMBER, SAID HOUSING HAVING A BOTTOM WALL PROVIDED WITH AN APERTURE THEREIN, A BODY OF A LIQUID ELECTROLYTE CARRIED BY SAID HOUSING AND THE CHAMBER DEFINED THEREBY, AN ELONGATED REFERENCE ELECTRODE ROD IN SAID HOUSING AND BEING PARTIALLY IMMERSED IN SAID LIQUID ELECTROLYTE BODY BUT HAVING AT LEAST ONE END THEREOF DISPOSED OUTWARDLY OF SAID LIQUID ELECTROLYTE BODY, AN ELONGATED NON-POROUS SENSING ELECTRODE ROD IN SAID HOUSING IN SPACED RELATION TO SAID REFERENCE ELECTRODE ROD AND BEING PARTIALLY IMMERSED IN SAID LIQUID ELECTRODE BODY BUT HAVING BOTH ENDS THEREOF DISPOSED OUTWARDLY OF SAID LIQUID ELECTROLYTE BODY, ONE END SURFACE OF SAID NON-POROUS SENSING ELECTRODE ROD COMPRISING A SENSING SURFACE TO WHICH GAS TO BE MONITORED IS ADAPTED TO BE EXPOSED, THE END OF SAID NON-POROUS SENSING ELECTRODE ROD OPPOSITE FROM THE END THEREOF ON WHICH SAID SENSING SURFACE IS PROVIDED EXTENDING THROUGH THE APERTURE IN THE BOTTOM WALL OF SAID HOUSING IN LIQUID-TIGHT SEALED RELATION TO THE BOTTOM WALL OF SAID HOUSING, COVER MEANS CLOSING THE TOP OF SAID HOUSING IN LIQUID-TIGHT SEALED RELATION, SAID COVER MEANS INCLUDING AN INLET PASSAGEWAY IN COMMUNICATION WITH SAID SENSING SURFACE OF SAID NON-POROUS SENSING ELECTRODE ROD FOR INTRODUCING A GASOUS BODY INTO THE INTERIOR OF THE CHAMBER, METER MEANS ELECTRICALLY CONNECTED BETWEEN SAID AT LEAST ONE END OF SAID REFERENCE ELECTRODE ROD AND THE END OF SAID NON-POROUS SENSING ELECTRODE ROD OPPOSITE FROM THE END THEREOF ON WHICH SAID SENSING SURFACE IS PROVIDED, AN ELONGATED HYDROPHILIC POROUS FIBER WICK EXTENDING TRANSVERSELY ACROSS SAID SENSING SURFACE OF SAID NON-POROUS SENSING ELECTRODE ROD AND INTO PARTIAL IMMERSION WITH SAID LIQUID ELECTROLYTE BODY FOR PROVIDING A SMALL QUANTITY OF THE LIQUID ELECTROLYTE ACROSS SAID SENSING SURFACE THROUGH CAPILLARY ATTRACTION AND ABSORPTION BY SAID POROUS FIBER WICK OF THE LIQUID ELECTROLYTE TO COMPLETE AN OHMIC CONNECTION, SAID POROUS FIBER WICK HAVING A RELATIVELY SMALL DIAMETRAL DIMENSION AS COMPARED TO THE WIDTH OF SAID SENSING SURFACE AND COVERING ONLY A MINOR PORTION OF THE AREA OF SAID SENSING SURFACE, AND SAID COVER MEANS FURTHER INCLUDING A GAS-PERMEABLE MEMBRANE DISPOSED IN SAID INLET PASSAGEWAY IN ALIGNMENT WITH SAID SENSING SURFACE AND IN SPACED RELATION TO SAID POROUS FIBER WICK.

Claim 4

AN ELECTRO-CHEMICAL GAS DETECTION SYSTEM, COMPRISING: A HOUSING DEFINING A CHAMBER, SAID HOUSING HAVING A BOTTOM WALL PROVIDED WITH AN APERTURE THEREIN, A BODY OF A LIQUID ELECTROLYTE CARRIED BY SAID HOUSING AND THE CHAMBER DEFINED THEREBY, AN ELONGATED REFERENCE ELECTRODE ROD IN SAID HOUSING AND BEING PARTIALLY IMMERSED IN SAID LIQUID ELECTROLYTE BODY BUT HAVING AT LEAST ONE END THEREOF DISPOSED OUTWARDLY OF SAID LIQUID ELECTROLYTE BODY, AN ELONGATED NON-POROUS SENSING ELECTRODE ROD IN SAID HOUSING IN SPACED RELATION TO SAID REFERENCE ELECTRODE ROD AND BEING PARTIALLY IMMERSED IN SAID LIQUID ELECTRODE BODY BUT HAVING BOTH ENDS THEREOF DISPOSED OUTWARDLY OF SAID LIQUID ELECTROLYTE BODY, ONE END SURFACE OF SAID NON-POROUS SENSING ELECTRODE ROD COMPRISING A SENSING SURFACE TO WHICH GAS TO BE MONITORED IS ADAPTED TO BE EXPOSED, THE END OF SAID NON-POROUS SENSING ELECTRODE ROD OPPOSITE FROM THE END THEREOF ON WHICH SAID SENSING SURFACE IS PROVIDED EXTENDING THROUGH THE APERTURE IN THE BOTTOM WALL OF SAID HOUSING IN LIQUID-TIGHT SEALED RELATION TO THE BOTTOM WALL OF SAID HOUSING, COVER MEANS CLOSING THE TOP OF SAID HOUSING IN LIQUID-TIGHT SEALED RELATION, SAID COVER MEANS INCLUDING AN INLET PASSAGEWAY IN COMMUNICATION WITH SAID SENSING SURFACE OF SAID NON-POROUS SENSING ELECTRODE ROD FOR INTRODUCING A GASOUS BODY INTO THE INTERIOR OF THE CHAMBER, METER MEANS ELECTRICALLY CONNECTED BETWEEN SAID AT LEAST ONE END OF SAID REFERENCE ELECTRODE ROD AND THE END OF SAID NON-POROUS SENSING ELECTRODE ROD OPPOSITE FROM THE END THEREOF ON WHICH SAID SENSING SURFACE IS PROVIDED, AN ELONGATED HYDROPHILIC POROUS FIBER WICK EXTENDING TRANSVERSELY ACROSS SAID SENSING SURFACE OF SAID NON-POROUS SENSING ELECTRODE ROD AND INTO PARTIAL IMMERSION WITH SAID LIQUID ELECTROLYTE BODY FOR PROVIDING A SMALL QUANTITY OF THE LIQUID ELECTROLYTE ACROSS SAID SENSING SURFACE THROUGH CAPILLARY ATTRACTION AND ABSORPTION BY SAID POROUS FIBER WICK OF THE LIQUID ELECTROLYTE TO COMPLETE AN OHMIC CONNECTION, SAID POROUS FIBER WICK HAVING A RELATIVELY SMALL DIAMETRAL DIMENSION AS COMPARED TO THE WIDTH OF SAID SENSING SURFACE AND COVERING ONLY A MINOR PORTION OF THE AREA OF SAID SENSING SURFACE, AND SAID COVER MEANS FURTHER INCLUDING A GAS-PERMEABLE MEMBRANE DISPOSED IN SAID INLET PASSAGEWAY IN ALIGNMENT WITH SAID SENSING SURFACE AND IN SPACED RELATION TO SAID POROUS FIBER WICK.