Method of adjusting output of gas sensor

Abstract

A method of adjusting an output of a gas sensor element is provided. The gas sensor element includes a lamination of a solid electrolyte body, a target gas-exposed electrode, a reference gas-exposed electrode, and a diffused resistance layer in which a target gas to be measured diffuses. The target gas-exposed electrode is disposed on a first surface of the solid electrolyte body exposed to the target gas. The reference gas-exposed electrode is disposed on a second surface of the solid electrolyte body exposed to a reference gas. The diffused resistance layer is disposed on the first surface of the solid electrolyte body. The target gas-exposed electrode and the reference gas-exposed electrode produce a sensor output. The adjustment of the sensor output is achieved by decreasing a diffusion length of the target gas in the diffused resistance layer as a function of a quantity of the sensor output to be adjusted by, for example, removing a portion of the diffused resistance layer.

What is claimed is:  
     
         1 . A gas sensor output adjusting method comprising: 
 preparing a gas sensor element including a lamination of a solid electrolyte body, a target gas-exposed electrode, a reference gas-exposed electrode, and a diffused resistance layer in which a target gas to be measured diffuses, the target gas-exposed electrode being disposed on a first surface of the solid electrolyte body exposed to the target gas, the reference gas-exposed electrode being disposed on a second surface of the solid electrolyte body exposed to a reference gas, the diffused resistance layer being disposed on the first surface of the solid electrolyte body, the target gas-exposed electrode and the reference gas-exposed electrode producing a sensor output; and    decreasing a diffusion length of the target gas in the diffused resistance layer as a function of a quantity of the sensor output to be adjusted.    
     
     
         2 . A gas sensor output adjusting method as set forth in  claim 1 , wherein the decreasing the diffusion length is achieved by removing a portion of the diffused resistance layer.  
     
     
         3 . A gas sensor output adjusting method as set forth in  claim 1 , wherein said diffused resistance layer includes a porous layer and a dense layer and wherein the decreasing the diffusion length is achieved by removing a portion of the porous layer.  
     
     
         4 . A gas sensor output adjusting method as set forth in  claim 1 , wherein said diffused resistance layer includes a porous layer and wherein the decreasing the diffusion length is achieved by removing a portion of the porous layer.  
     
     
         5 . A gas sensor output adjusting method as set forth in  claim 1 , wherein said diffused resistance layer includes a porous layer and a dense layer and wherein the decreasing the diffusion length is achieved by removing a portion of the dense layer.  
     
     
         6 . A gas sensor output adjusting method comprising: 
 preparing a gas sensor element including a lamination of a solid electrolyte body, a target gas-exposed electrode, a reference gas-exposed electrode, and a diffused resistance layer in which a target gas to be measured diffuses, the target gas-exposed electrode being disposed on a first surface of the solid electrolyte body exposed to the target gas, the reference gas-exposed electrode being disposed on a second surface of the solid electrolyte body exposed to a reference gas, the diffused resistance layer being disposed on the first surface of the solid electrolyte body, the target gas-exposed electrode and the reference gas-exposed electrode producing a sensor output; and    decreasing a gas-diffusing sectional area of the diffused resistance layer within which the target gas diffuses as a function of a quantity of the sensor output to be adjusted.    
     
     
         7 . A gas sensor output adjusting method as set forth in  claim 6 , wherein said diffused resistance layer includes a porous layer and a dense layer and wherein the decreasing the gas-diffusing sectional area of the diffused resistance layer is achieved by partially sealing a surface of the porous layer exposed to the target gas.  
     
     
         8 . A gas sensor output adjusting method as set forth in  claim 6 , wherein said diffused resistance layer includes a porous layer and a dense layer and wherein the decreasing the gas-diffusing sectional area of the diffused resistance layer is achieved by forming a plurality of output-adjusting holes in the dense layer which lead to the porous layer and sealing a given number of the output-adjusting holes as a function of the quantity of the sensor output to be adjusted.  
     
     
         9 . A gas sensor output adjusting method comprising: 
 preparing a gas sensor element including a lamination of a solid electrolyte body, a target gas-exposed electrode, a reference gas-exposed electrode, and a diffused resistance layer in which a target gas to be measured diffuses, the target gas-exposed electrode being disposed on a first surface of the solid electrolyte body exposed to the target gas, the reference gas-exposed electrode being disposed on a second surface of the solid electrolyte body exposed to a reference gas, the diffused resistance layer having an outer surface exposed to the target gas, an inner surface opposite the outer surface, disposed on the first surface of the solid electrolyte body, and side surfaces formed between the outer and inner surfaces, defining portions of side surfaces of the lamination, the target gas-exposed electrode and the reference gas-exposed electrode producing a sensor output; and    decreasing a diffusion length of the target gas in the diffused resistance layer as a function of a quantity of the sensor output to be adjusted by removing a portion of the diffused resistance layer obliquely to at least one of the side surfaces of the lamination.