Inner terminal installation jig used to install an inner electrode terminal

An inner terminal installation jig used to install an inner electrode terminal on an inner terminal mount formed on an inner peripheral surface of a hollow cylindrical sensor element of a gas sensor, the inner electrode terminal having an annular holder whose outer diameter is greater than an inner diameter of the inner terminal mount, comprising:

• a member of a given length which has a first and a second end opposed to each other and a through hole extending from the first to the second end, the through hole tapering off to the first end, an inner diameter of an opening of the through hole formed in the first end being smaller than or equal to the inner diameter of the inner terminal mount of the sensor element, an outer diameter of an opening of the through hole formed in the second end being greater than an outer diameter of the annular holder of the inner electrode terminal before installed in the cylindrical sensor element;
• and
• a recess formed in the first end of said member in communication with the through hole, said recess being configured to establish engagement of said member with an end of the cylindrical sensor element for installing the inner electrode terminal on the inner terminal mount of the cylindrical sensor element.