Air-fuel ratio sensor

Claim 2

AN EXHAUST GAS SENSOR FOR MEASURING THE RELATIVE PRESENCE OF OXYGEN IN THE EXHAUST GAS COMPRISING: A HOLLOW OUTER METAL SHELL HAVING A BODY SECTION THAT IS ADAPTED TO BE MOUNTED IN AN EXHAUST SYSTEM, INSULATOR MEANS SECURED WITHIN SAID HOLLOW METAL SHELL, SAID BODY SECTION HAVING A SHOULDER THEREIN THAT IS ADAPTED TO HOLD ONE END OF A HOLLOW CYLINDRICAL ZIRCONIA CELL IN FIXED POSITION, FASTENER MEANS THAT INCLUDES A BOLT PORTION ALSO HAVING A SIMILAR SHOULDER THEREON IN ALIGNMENT WITH THE SHOULDER ON SAID BODY SECTION TO HOLD THE OTHER END OF THE ZIRCONIA CELL, SAID FASTENER MEANS EXTEND THROUGH SAID ZIRCONIA CELL, SAID INSULATOR MEANS, AND SAID HOLLOW OUTER METAL SHELL, AND IS HELD IN FIXED POSITION AGAINST THE TOP OF SAID INSULATOR MEANS BY A SECURING MEANS TO CREATE A SEAL BETWEEN SAID ZIRCONIA CELL, SAID BODY SECTION, AND SAID FASTENER MEANS TO PREVENT EXHAUST GASES FROM ENTERING THE INTERIOR OF THE ZIRCONIA CELL, THE BOLT PORTION OF SAID FASTENER MEANS BEING SMALLER

Claim 3

An exhaust gas sensor for measuring the relative presence of oxygen in the exhaust gas comprising: a hollow outer metal shell having a body section extending therefrom that is adapted to be mounted in an exhaust system, insulator means secured within said hollow outer metal shell; said body section having a shoulder thereon positioned within the exhaust system that positions and retains one end of a hollow cylindrical zirconia cell in fixed position against the shoulder and the bottom of said body section, fastener means that includes a bolt portion having threads at one end and a shoulder similar to the shoulder on said body section at the other end in alignment with the shoulder on said body section to hold the other end of the zirconia cell in alignment therewith, said fastener means extends through said insulator means, said zirconia cell, and said hollow outer metal shell, and is held in fixed position against the top of said insulator by a nut and washer to hold said fastener means in a fixed position to create a seal between said fastener means, said zirconia cell, and said body section to prevent exhaust gases from entering the interior of the zirconia cell, the bolt portion of said fastener means being smaller in diameter than the inside of said insulator, said outer shell, and said zirconia cell, to permit air to enter into said zirconia cell from a plurality of openings in said insulator means, said zirconia cell having a platinum coating on the inside surface that extends over the end surface in contact with said fastener means to form an inner electrode, and a similar platinum coating on the outside surface that extends over the end surface in contact with said body section to form an outer electrode, with the inside and outside surfaces of said zirconia cell being uncoated at a section adjacent the ends of said zirconia cell to thereby insulate the inner electrode from the outer electrode, one of said electrodes and said hollow outer metal shell forming a first contact means and the other of said electrodes and said fastener means forming a second contact means.

Claim 4

An exhaust gas sensor for measuring the relative presence of oxygen in the exhaust gas comprising: a hollow outer metal shell having a body section extending therefrom that is adapted to be mounted in an exhaust system, insulator means secured within said hollow outer metal shell; said body section having a shoulder thereon positioned within the exhaust system that positions and retains one end of a hollow cylindrical zirconia cell in fixed position against the shoulder and the bottom of said body section, fastener means that includes a bolt portion having threads at one end and a shoulder similar to the shoulder on said body section at the other end in alignment with the shoulder on said body section to hold the other end of the zirconia cell in alignment therewith, said fastener means extends through said insulator means, said zirconia cell, and said hollow outer metal shell, and is held in fixed position against the top of said insulator by a nut and washer to hold said fastener means in a fixed position to create a seal between said fastener means, said zirconia cell, and said body section to prevent exhaust gases from entering the interior of the zirconia cell, the bolt portion of said fastener means being smaller in diameter than the inside of said insulator, said outer shell, and said zirconia cell, to permit air to enter into said zirconia cell from a plurality of openings in said insulator means, said zirconia cell having a platinum coating on the inside surface that extends over the end surface in contact with said fastener means to form an inner electrode, and a similar platinum coating on the outside surface that extends over the end surface in contact with said body section to form an outer electrode, with the inside and outside surfaces of said zirconia cell being uncoated at a section adjacent the ends of said zirconia cell to thereby insulate the inner electrode from the outer electrode, one of said electrodes and said hollow outer metal shell forming a first contact means and the other of said electrodes and said fastener means forming a second contact means.