Method for making evaporator or condenser construction

Claim 1

In a method for making an evaporator or condenser construction for refrigeration apparatus the steps of providing at least two elongated main metal tubes defining a plurality of main tube ends, each of said main tubes having substantially uniform inside and outside diameters throughout the length thereof and having a mill stock finish, providing at least one generally U-shaped connector tube having substantially uniform inside and outside diameters throughout the length thereof and a mill stock finish and defining a pair of connector tube ends, said main tube ends and said connector tube ends having such relative inside and outside diameters that said U-shaped connector tube may have each of its two tube ends telescopically assembled with an associated one of said main tube ends to form a connection consisting of two joints each involving one tube end inserted in another tube end, thrusting said main tubes through heat exchanged plates and in general parallel relation, forming only a radially inwardly directed bead on the larger diameter tube end of each proposed joint and which bead is spaced from the adjacent open end of said larger diameter tube end to define a socket between said open end and said bead, said socket having an inside diameter equal to the inside diameter of the remainder of the tube in which it is formed and an interior surface having a mill stock finish, assembling each tube end of said connector tube telescopically with an associated one of the pair of the pair of main tube ends to bring the smaller diameter tube end of each joint into abutting relation with an associated bead, applying a solder bonding material around each end portion of said smaller diameter tube end of each joint and generally adjacent the open end of said larger diameter tube end of each joint, heating each joint to cause said bonding material to flow and thereby to run it into any space between the end portion of each tube to be connected and the associated end portion of the end of the connector tube and cooling each joint to achieve fluid type solidification of the bonding material.