Abstract

An electric soldering iron includes an elongated metal housing tube enclosing a metallic heat conducting member having a first zone snugly fit within the housing and having a portion projecting out of the front end thereof for removably receiving a soldering tip. A second zone of the member extends rearwardly from the first zone and has a smaller cross section than the interior of the tube to create an insulating space therebetween. The heat conducting member is formed with an opening sized and shaped to receive the end of an elongated flat ceramic heater having embedded therein an electric heating element. The portion of the ceramic heater not located within the heat conducting member is surrounded and positioned by a refractory heat insulating tube abutting the rear end of the heat conducting member. The other end of the tube is closed by a male electrical terminal unit adapted to be removably connected to a female terminal unit at the front end of a soldering iron handle for mechanically attaching the heating unit to the handle and electrically connecting the heating element of the ceramic heater to power supply wires in the handle. Since the heat conducting member engages the housing tube only at the end where the tip is attached heat is preferentially directed to the tip. The space formed by the second zone of the heat conducting member and the provision of the refractory tube thermally insulates the housing tube form the ceramic heater and further reduces the transfer of heat to the handle.