Sensor element for gas sensor
AssigneeNGK Insulators, Ltd.
InventorRyo ONISHI
Life of this patent
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Abstract
A sensor element includes an element base and a leading-end protective layer disposed around an outer periphery in a predetermined range at least including an end surface having a gas inlet, and being a porous layer including one or more unit layers, and a thickness Tj (j=1 to n: n is a natural number) in μm of a j-th unit layer from a side of the element base on the end surface, a porosity ρj in % of the j-th unit layer, and a distance Le in mm from the heater to the end surface of the element base satisfy a predetermined inequality on an end surface of the leading-end protective layer.
Claims10
A sensor element for a gas sensor, said sensor element comprising:
- an element base being a ceramic structure, said element base having an end surface having a gas inlet through which a measurement gas is introduced into said element base, and including a sensing part for sensing a gas component to be measured and a heater for heating said sensor element;
- and
- a leading-end protective layer disposed around an outer periphery of said element base in a predetermined range at least including said end surface, and being a porous layer including one or more unit layers, wherein
- said leading-end protective layer is provided on said end surface to satisfy
- 1
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- where Tj (j=1 to n:
- n is a natural number) is a thickness in μm of a j-th unit layer of said leading-end protective layer from a side of said element base on said end surface, ρj is a porosity in % of said j-th unit layer, and Le is a distance in mm from said heater to said end surface.
Dependencies are inferred from the claim text.