Temperature control system for liquid chromatographic columns employing a thin film heater/sensor

A temperature control system for a liquid chromatographic column comprising in combination:

• a thin film heater for removable wrap mounting about the exterior surface of a liquid chromatographic column, comprising at least one foil-like patterned heating elements adhesively mounted between upper and lower flexible, electrically insulative layers and including at least one patterned foil-like temperature sensing element integrally coextensively mounted in temperature sensing relation to said at least one heating element:
• retainer means comprising a spirally tubularly wound length of flexible wrapping, the windings of which may be unwound but which return to their unflexed shape when released, having a cross-sectional bore area less than that of a thin film heater wrapped column for uniformly compressively securing the wrapped thin film heater in heat transfer relation to the liquid chromatographic column;
• and
• means responsively coupled to said at least one sensing element for controlling the watt density applied to said at least one heating element in a linear proportional fashion, thereby maintaining a predetermined temperature profile over the length of said column.

A temperature control system comprising in combination:

• a thin film heater for removable wrap mounting about the exterior surface of a member to be heated, comprising a foil-like patterned heating element having a plurality of heating zones adhesively mounted between upper and lower flexible, electrically insulative layers and including a plurality of patterned foil-like temperature sensing elements integrally coextensively mounted in coplanar and temperature sensing relation to respective ones of said heating zones;
• retainer means comprising a spirally tubularly wound length of flexible wrapping the windings of which may be unwound but which return to an unflexed shape when released, having a cross-sectional bore area less than that of said member when wrapped with said thin film heater for uniformly compressively securing the wrapped thin film heater to the member upon wrapping said retainer means therearound;
• and
• means responsively coupled to each of said plurality of temperature sensing elements for controlling the watt density applied to each of said plurality of heating zones in a linear proportional fashion, thereby maintaining a predetermined temperature gradient over the length of said member.