Patent ID: 6920919
Filing Date: 2005-07-26
Classification: F28D

Abstract:
1. A heat exchanger comprising: a first tube of generally circular cross section and having an internal diameter of relatively large size, said first tube being generally U-shaped with opposite ends adjacent to one another; a second tube having a circular cross section that is relatively small in relation to said relatively large size and with opposed ends and, intermediate said opposed ends, being in a helical configuration having an external diameter about that of said relatively large size or less; said second tube helical configuration being located within said first tube with said opposed ends extending out of said opposite ends of said first tube; hollow headers impaled by said first tube adjacent each said opposite end of said first tube and sealed thereto; a port in said first tube adjacent each said opposite end and aligned with and in fluid communication with a corresponding one of said headers; a cap on each of said opposite ends of said first tube and sealed thereto; and an aperture in each said cap sized to receive a corresponding one of said opposed ends of said second tube and to allow the corresponding one of said opposed ends to extend past said cap; said caps and each said corresponding one of said opposed ends of said second tube being sealed to each other at the corresponding aperture.