US Patent 7086135 Method and apparatus for manufacturing glow plug

A method for manufacturing a glow plug, the glow plug comprising a cylindrical metal shell having an internal bore formed in an axial direction, and a heater tube adapted to be press-fitted from its rear end side into the internal bore and having a leading end closed, the method comprising the steps of: place a stopper abutting on the leading end; and applying an axial load between the stopper and the metal shell so as to start a clamping of a side of the heater tube through a support member and to start a press-fit of the heater tube in the metal shell and an apparatus for manufacturing the glow plug.