A ceramic heater according to one aspect of the present invention has a cylindrical ceramic heater and an annular metal flange fitted around the ceramic heater. In the ceramic heater, one side of the flange with respect to an axial direction of the heater body is concave in the axial direction to define a concave part. The concave part includes a glass accumulation region filled with a glass material. The glass material in the glass accumulation is fused to the flange and to the heater body.

A ceramic heater according to one aspect of the present invention has a cylindrical ceramic heater and an annular metal flange fitted around the ceramic heater. In the ceramic heater, one side of the flange with respect to an axial direction of the heater body is concave in the axial direction to define a concave part. The concave part includes a glass accumulation region filled with a glass material. The glass material in the glass accumulation is fused to the flange and to the heater body.

A resistance element includes a resistance coil having a first end and a second end opposite the first end. The resistance coil defines a plurality of first portions defining a first constant diameter and a plurality of second portions defining a second constant diameter smaller than the first diameter. At least one of the first portions and the second portions has a continuously variable pitch. The resistance coil may also further define two third portions, each third portion being disposed adjacent to a corresponding first or second end. The resistance element may be disposed between first and second conducting pins in a heater.

A resistance element includes a resistance coil having a first end and a second end opposite the first end. The resistance coil defines a plurality of first portions defining a first constant diameter and a plurality of second portions defining a second constant diameter smaller than the first diameter. At least one of the first portions and the second portions has a continuously variable pitch. The resistance coil may also further define two third portions, each third portion being disposed adjacent to a corresponding first or second end. The resistance element may be disposed between first and second conducting pins in a heater.

A splice for a skin-effect effect heating cable is provided. The splice includes a primary shim configured to be shrunk over part of an insulation layer of a first portion of the heating cable, a secondary shim configured to be shrunk part of the insulation layer of a second portion of the heating cable, a connector configured to electrically couple the first portion of the heating cable and the second portion of the heating cable, and an outer cold shrink tube configured to be shrunk over the primary shim, the secondary shim, and the connector.

A splice for a skin-effect effect heating cable is provided. The splice includes a primary shim configured to be shrunk over part of an insulation layer of a first portion of the heating cable, a secondary shim configured to be shrunk part of the insulation layer of a second portion of the heating cable, a connector configured to electrically couple the first portion of the heating cable and the second portion of the heating cable, and an outer cold shrink tube configured to be shrunk over the primary shim, the secondary shim, and the connector.

A heat transfer assembly includes a sheath which in one embodiment is elliptical in cross-section and in another embodiment has a complex cross-section with flat wall sections and curved wall sections. The sheath is elastically deformable so as to accept a heat transfer element sub-assembly. Once installed, the sheath holds the sub-assembly in place by an interference fit.

A heat transfer assembly includes a sheath which in one embodiment is elliptical in cross-section and in another embodiment has a complex cross-section with flat wall sections and curved wall sections. The sheath is elastically deformable so as to accept a heat transfer element sub-assembly. Once installed, the sheath holds the sub-assembly in place by an interference fit.

An electric heating device includes at least one PTC element, conductor tracks electrically connected to the PTC element for energizing the PTC element, and insulating layers abutting in a thermally conductive manner against the PTC element. At least one of the insulating layers comprises at least one duct for the passage of a fluid to be heated.

An electric heating device includes at least one PTC element, conductor tracks electrically connected to the PTC element for energizing the PTC element, and insulating layers abutting in a thermally conductive manner against the PTC element. At least one of the insulating layers comprises at least one duct for the passage of a fluid to be heated.