Patent ID: 8261445

Claim:
A method of forming an aluminum baseboard heat exchanger, comprising: (a) forming an elongated strip of sheet aluminum into a series of fin portions and spacer portions, each fin portion of said series of fin portions having a predetermined height H and width W and each of the said fin portions being joined to the next in said series by one of the a spacer portions having a predetermined spacing distance S and with each said fin portion having a central aperture formed therein; (b) bending said elongated strip into a serpentine fin array in which said fin portions are disposed generally parallel to one another and spaced apart by said spacer portions, said spacer portions joining successive ones of said fin portions and appearing alternately at a left side and a right side of said array, and such that the center apertures of said fin portions are aligned; (c) placing said serpentine fin assembly into an assembly fixture, the fixture having spacer members that are disposed to enter into voids formed between successive ones of said fin portions; (d) inserting a thermally conductive aluminum center tube through the aligned center apertures in said fin assembly such that the aluminum tube contacts and deforms the fin portions at said openings to create an interference fit of the tube with each of said fin portions; and resulting with one end of the tube projecting from said fin assembly; (e) affixing a connector nipple into said one end portion of the aluminum center tube, the connector nipple having a male portion fitting to said one end portion and having a gripping structure formed on an outer surface to mate with an inside surface of said one end portion of the aluminum center tube; and (f) deforming said one end portion of said aluminum center tube inward to flow the material thereof onto said gripping structure to create a hermetic seal between said tube and said connector nipple; wherein said step of deforming includes closing a jaw arrangement onto said one end of the center tube, the jaw arrangement comprising a plurality of jaw members applying a compressive force thereon around the circumference of the end portion of the tube, the compression force being of a sufficient level to compress the aluminum center tube radially inward against the male portion of said connector nipple, wherein there are a sufficient number of said jaw members so that the deformation of the one end of the aluminum center tube is made smooth and even over the circumference thereof, and wherein the step of deforming includes sliding the jaw arrangement, while held closed, along the one end portion of the center tube in a longitudinal direction of the tube.