US Patent 9648983 Helical dynamic flow through heater

A flow though heater device comprising a fluid tube carrying a fluid to be heated, a tubular heating element extending at least partially parallel and in thermal contact with the fluid tube, wherein the tubular heating element comprises a profiled casing tube and at least one heating coil mounted in a tubular portion of said profiled casing tube. The profiled casing tube further comprises at least one tab portion laterally protruding from the tubular portion and being wrapped around the fluid tube, wherein the assembly of the fluid tube and the tubular heating element has an approximately helical shape so that the tubular portion of the casing tube is positioned with respect to the helix radially inside of the fluid tube.