LAMINATED-TYPE OXYGEN SENSOR ELEMENT, ITS MANUFACTURING METHOD, AND OXYGEN SENSOR

摘要

PROBLEM TO BE SOLVED: To provide a laminated-type oxygen sensor element to suppress current leakage between solid electrolyte layers, its manufacturing method, and an oxygen sensor in which leakage does not occur between the element and main body metal fixture. SOLUTION: An oxygen concentration cell element in which a detecting electrode and reference electrode are formed and a ceramic heater in which a heating resistor embedded in an insulating layer is sandwiched by heater main body layers are laminated. An insulating coating 29 is formed in both side surfaces 27a and 27b and a face on the side to be exposed to a gas to be measured. Both longitudinal edges of the surface of the ceramic heater in which heater energizing terminals 25a and 25b are formed are chamfered. The insulating coating 29 is also formed in the surfaces formed by the chamfering in the laminated-type oxygen sensor element. Such the element superior in insulation is used to obtain the compact oxygen sensor in which leakage does not occur even if the element and main body metal fixture are close to each other and the minimum distance between them is 1 mm or less.