| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a highly reliable oxygen sensor element capable of preventing the occurrences of a crack due to a rapid temperature rise while maintaining the strength of the element. <P>SOLUTION: The oxygen sensor element comprises a sensor section having a plate-shaped solid electrolyte substrate 22 whose end is sealed in which an air inlet hole 22a is formed. A reference electrode 23 is formed on an inner wall of the air inlet hole 22a. A measuring electrode 24 of platinum is formed on a surface of the substrate 22 opposite to the reference electrode 23. The length Ws of an end face of the air inlet hole 22a located on the side of the reference electrode 23 as taken in a direction perpendicular to the direction of the length of the element inside the air inlet hole 22a is greater than the width W of the reference electrode 23 as taken in the direction perpendicular to the direction of the length of the element, and greater than the length Wh of the opposite end face of the air inlet hole 22a. <P>COPYRIGHT: (C)2004,JPO |
