Watkins, Dunbar & Pollick
Heat transfer apparatus
 A refrigeration and heating system has been made in which improved efficiencies are obtained by placing helical concentric coils of at least two generators (80 and 81) and recuperators (86 and 95) on a common axis (232) with a heating unit (84) at the center and allowing the hot combustion gases (245) to circulate in serpentine fashion through separate concentric chambers containing the coils. Further efficiencies are obtained by placing an absorber (97), condenser (100) and recuperator (107) in a single module (270) and by using tube-in-tube or tube-in-cylinder construction with fluted inner tubes. A general purpose, divided-flow, tube-in-cylinder, heat-transfer device (400) is used to reduce the pressure drop in the circulating fluid. 
Columbia Gas System Service Corporation
F F F F Y Y
F25B F25B F28F F28D Y02A Y02B
inventional inventional additional inventional additional additional
F. Bert Kevin R. Richard N. Howard C. Stephen E.
Cook McGahey Christensen Meacham, Jr. Petty