Heater and method of making same

A heater comprising:

• a metallic tubular sheath;
• an elongate, solid metal center conductor;
• fibrous, inorganic electrical insulation material enwrapped around said center conductor;
• an elongate electrical resistance heating element wrapped around said insulated center conductor, said heating element being substantially coaxial with said center conductor;
• said insulated center conductor with heating element thereon being positioned substantially coaxially within said sheath with one end of said center conductor extending out beyond one end of said sheath, said center conductor being electrically connected to said heating element within said sheath adjacent the other end of said center conductor, said one end of said center conductor being adapted to be connected to a source of electrical power and constituting a terminal for said heater;
• a sleeve of electrically conductive material fitted on said center conductor and being electrically insulated therefrom by said insulation material, said sleeve being in electrical contact with said heating element and extending out from said one end of said sheath, said sleeve being adapted to be electrically connected to a source of electrical power and thus constituting a second terminal for said heater, said first and second terminals extending from the same end of said sheath;
• and
• other electrical insulation material disposed between said heating element and said sheath and between said sleeve and said sheath thereby to electrically insulate the heating element from the sheath, to provide a conductive heat transfer path between the heating element and the sheath, and to electrically insulate the sleeve from said sheath.