Immersion heater

Claim 1

A continuous, flexible heating cable assembly array for immersion heating of a liquid in a container, said cable array comprising: (a) a heating element disposed in coiled pitches of substantially uniform diameter having a length substantially greater than the coil diameter, said element being formed of a continuous bare wire having a high electrical resistance; (b) a flexible braided sheath of fibrous glass material received over said coiled pitches continuously along the length thereof; (c) said coil heating element having at least one uncoiled region disposed intermediate the ends thereof and intermediate to regions of said coiled pitches, which region has the element disposed in axially substantially linear arrangement for a predetermined interval of length; (d) an outer tubular casing formed of flexible, electrical insulating material having a low surface coefficient of friction and a high resistance to heat and attacks by acid and alkaline solutions, said casing being received over said sheath element and continuous along the length thereof; (e) connecting means attached to each end of said coiled element and disposed within said casing; (f) power lead means attached to each of said connecting means, said lead means extending beyond the respective adjacent end of said casing, said lead means being adapted for connection to a source of electrical power; (g) said cable assembly being folded or bent at a radius less than twice the diameter of said casing in said uncoiled region without materially disturbing said coiled pitches wherein said cable assembly has a plurality of said uncoiled regions spaced therealong and forms an array of side-by-side closely spaced, unbent sections disposed in generally serpentine arrangement; (h) support means; and, (i) means for attaching the individual sections to said support means for maintaining said side-by-side closely spaced serpentine arrangement.