摘要:
An oxygen sensor with an oxygen sensor element having an outer protective layer of alumina, acting as getters with respect to catalyst poisons, particularly phosphorus, in exhaust gases, formed on the outer surface of a catalyst layer of platinum or a mixture of platinum and rhodium which is coated on an electrode protective layer provided on the outer electrode of an oxygen sensor element. Such an outer protective layer is additionally provided on the inner wall of the inner louver of the oxygen sensor having a double louver structure. A method of manufacturing an oxygen sensor with an oxygen sensor element comprising the steps of coating such an outer alumina protective layer onto the outer surface of said catalyst layer formed on an electrode protective layer provided onto the outer electrode of an oxygen sensor element and additionally coating such an alumina protective layer onto the inner wall of the inner louver of an oxygen sensor having a double louver structure.
摘要:
A catalyst supported oxygen sensor element detecting the oxygen concentration in exhaust gas from vehicle engines is composed of a tubular container of a solid ion-conductive electrolyte with the one end portion thereof closed, an inner electrode being positioned on the inner circumference of the container, an outer electrode being positioned on the outer circumference, a protective layer of a refractory material being provided on the outer circumference of the outer electrode, a catalyst layer being provided on the outer circumference of the protective layer, and optionally provided on the outer circumference of the catalyst layer, and a method of manufacturing the same.
摘要:
An oxygen sensing element capable of measuring partial pressures of oxygen in sample gases, which element has a solid electrolyte member having totally embedded therein a means for providing a reference partial pressure of oxygen composed of a sintered product of a finely divided metal or metal-metal oxide mixture and having a lead-out wire connected thereto is prepared by a method wherein: p1 (a) a part of the finely divided solid electrolyte material is compression-molded to form a provisional solid electrolyte member having a hole;(b) a provisional product of the reference oxygen partial pressure-providing means is formed in the hole of the provisional solid electrolyte member from the finely divided metal or metal-metal oxide mixture;(c) the remaining part of the finely divided solid electrolyte material is piled up on the provisional reference oxygen partial pressure-providing means product, followed by compression molding the piled up solid electrolyte material to form an integrated structure comprising the solid electrolyte member having totally embedded therein the provisional reference oxygen partial pressure-providing means;(d) the integrated structure is sintered in a non-oxidizing atmosphere at approximately 1,350.degree. to 1,500.degree. C.; and,(e) a layer or layers of an external conductive metal electrode or electrodes is formed on at least a part of the exterior surface of the sintered product.
摘要:
A protective layer of a refractory material deposited on a metal electrode layer of an oxygen sensing element is improved by a process comprising forming the protective layer onto the surface of the metal electrode layer by plasma spray coating the surface of the metal electrode layer, first with a refractory material powder at a position of a prescribed distance from a plasma spray coating device and at a prescribed electric power, and second, with a refractory material powder having the same particle size and composition as said refractory material powder used in the first plasma spray coating at a position of a distance greater than said prescribed distance and/or at an electric power lower than said prescribed electric power.
摘要:
The high temperature durability of an oxygen sensing element, which comprises a solid electrolyte member composed of sintered material, and a means for providing a reference oxygen partial pressure, composed of a sintered product of a finely divided metal or metal-metal oxide mixture powder and being completely embedded within the solid electrolyte member, is improved by incorporating in the finely divided metal or metal-metal oxide mixture powder an antisintering material and a pore-forming material capable of subliming or being decomposed, thereby to generate gas upon sintering. The amounts of the antisintering material and the pore-forming material are from 5 to 70% by weight and from 20 to 80% by weight, respectively, based on the total weight of these additives-incorporated metal or metal-metal oxide mixture. The low temperature operation capability of the oxygen sensing element is improved by further incorporating therein a minor amount of a platinum group metal.
摘要:
In an oxygen concentration cell having metal electrodes formed on both inner and outer wall surfaces of its solid electrolyte vessel and a solid pole as a reference oxygen partial pressure source made of a metal alone or a mixture of a metal and an oxide of the metal filled in said vessel, a method of activating said oxygen concentration cell by heat-treating the cell so as to diffuse the metal of said reference oxygen partial pressure source into said metal electrode on the inner wall or into said solid electrolyte through the metal on the inner wall surface and the oxygen concentration cell produced by this method.
摘要:
Low temperature operability of an oxygen sensing element, which comprises a solid electrolyte member composed of sintered material, and a means for providing a reference oxygen partial pressure, composed of a sintered product of a finely divided metal or metal-metal oxide mixture powder and being completely embedded within the solid electrolyte member, is improved by the incorporation of from 0.5 to 10% by weight, based on the total weight of the sintered product, of a finely divided platinum group metal powder in the sintered product of the reference oxygen partial pressure-providing means.
摘要:
An oxygen sensor element is manufactured by successively forming on the outside of the output lead wire, a solid pole, a first metal electrode layer, a solid electrolyte layer, and a second metal electrode layer from inside to outside.
摘要:
A solid pole oxygen sensor having a solid pole, in which one end of a lead wire of platinum or platinum rhodium is buried, tightly covered by a solid electrolyte and pressure-molded into a circular plate, which is dried and then fired in a reducing atmosphere. The surface of a sintered mass thus obtained is plated or baked to form a platinum electrode, and the oxygen sensor element thus obtained is secured by a bonding agent to the tip of a cylindrical ceramic insulator having electroconductive zones to be connected to the platinum electrode in such a manner that the circular face of the circular plate-shaped oxygen sensor element is in contact with the tip surface of the cylindrical ceramic insulator.
摘要:
A solid pole oxygen sensor in which one end of a lead wire of platinum or platinum/rhodium is buried in a solid pole and the surfaces of the solid pole and the lead wire are coated with an electroconductive paste. The solid pole is wrapped or encased in a solid electrolyte, pressure-molded into a pellet, which is dried and then fired in a reducing atmosphere. The surface of the sintered mass thus obtained is then plated or baked to form a platinum electrode, and the oxygen sensor element thus obtained is fitted or secured to the tip of an approximately cylindrical ceramic insulator equipped with electroconductive zones to be connected to the platinum electrode.