Abstract: A spark electrode assembly and method of assembling same is disclosed. A ceramic housing having a cylindrical passage provides clearance for a conductive metal electrode. The electrode has a tubular body with rod shaped wires inserted at each end, the wires extending outwardly from the tubular body at each of its ends colinearly. During assembly, the wires are crimped into the tubular body in such a manner that the tubular body is deformed outwardly forming bosses. The bosses are of such a size as to cause an interference fit between the tubular body and the housing passage so that the electrode is captured within the housing. An impact force on the electrode forces the tubular body to expand radially outwardly, thereby further engaging the ceramic housing for holding the electrode in the housing. That part of the electrode body that is not in contact with the housing still has ample room to expand within the housing.

Abstract: A spark electrode assembly and method of assembling same is disclosed. A ceramic housing having a cylindrical passage provides clearance for a conductive metal electrode of rod construction. The electrode has a body portion having a relatively large diameter, an emitter portion of relatively smaller diameter extending concentrically from one side of the body portion, and an umbrella-shaped portion extending concentrically from the other side of the body portion. During assembly, the electrode is inserted into the passage of the ceramic housing until the umbrella portion of the electrode makes contact with an annular side wall of the passage. An impact force on the electrode forces the umbrella portion to expand radially outwardly, thereby engaging an annular groove portion of the ceramic housing for holding the electrode in the housing.