Method of making a finned heat exchange panel

Claim 1

THE METHOD OF MAKING A FINNED HEAT EXCHANGE PANEL COMPRISING THE STEPS OF (A) FORMING A COMPOSITE OF A PAIR OF SHEETS OF METAL, ONE OF SAID SHEETS HAVING ON A CONFRONTING SURFACE THEREOF A PATERN OF WELD PREVENTING MATERIAL, (B) FORMING FROM METAL SHEET FIN STOCK A SUBSTANTIALLY FLAT STACK OF A PLURALITY OF OVERLAPPED AND STEPPED LAYERS WITHOPPOSITELY FACING END PORTIONS OF EACH LAYER EXTENDING BEYOND THE ENDS OF ADJACENT LAYERS, SAID LAYERS BEING COATED WITH WELD PREVENTING MATERIAL ON BOTH SIDES THEREOF EXCEPT FOR A RELATIVELY NARROW UNCOATED STRIP ADJACENT AT LEAST ONE LONGITUDINAL EDGE OF SAID LAYERS ON THE OUTER SURFACE THEREOF, SAID UNCOATED STRIP BEING DISPOSED ON AT LEAST ONE OF SAID OPPOSITELY FACING END PORTION, (C) FORMING A BLANK BY SUPERPOSING SAID STACK ON SAID COMPOSITE WITH SAID UNCOATED STRIPS OF SAID LAYERS IN CONTACT WITH SAID COMPOSITE, (D) FORMING AN INTEGRATED UNITARY STRUCTURE BY PRESSURE WELDING SAID SHEETS OF SAID COMPOSITE TOGETHER EXCEPT IN THE AREA OF SAID PATTERN OF WELD PREVENTING MATERIAL AND SIMULTANEOUSLY PRESSURE WELDING SAID STACK TO SAID COMPOSITE IN THE AREAS OF SAID UNCOATED STRIPS, (E) INFLATING THE UNJOINED PORTIONS OF SAID COMPOSITE BY INJECTING THEREINTO A FLUID UNDER PRESSURE THEREBY FORMING INTERIOR HOLLOW PASSEGEWAYS, AND (F) RAISING THE UNJOINED PORTIONS OF SAID LAYERS THEREBY PROVIDING INTEGRAL ERECT FINS OVERLYING SAID HOLLOW PASSAGEWAYS.

Claim 2

THE METHOD OF MAKING A FINNED HEAT EXCHANGE PANEL COMPRISING THE STEPS OF (A) FORMING A COMPOSITE OF A PAIR OF SHEETS OF METAL, ONE OF SAID SHEETS HAVING ON A CONFRONTING SURFACE THEREOF A PATERN OF WELD PREVENTING MATERIAL, (B) FORMING FROM METAL SHEET FIN STOCK A SUBSTANTIALLY FLAT STACK OF A PLURALITY OF OVERLAPPED AND STEPPED LAYERS WITHOPPOSITELY FACING END PORTIONS OF EACH LAYER EXTENDING BEYOND THE ENDS OF ADJACENT LAYERS, SAID LAYERS BEING COATED WITH WELD PREVENTING MATERIAL ON BOTH SIDES THEREOF EXCEPT FOR A RELATIVELY NARROW UNCOATED STRIP ADJACENT AT LEAST ONE LONGITUDINAL EDGE OF SAID LAYERS ON THE OUTER SURFACE THEREOF, SAID UNCOATED STRIP BEING DISPOSED ON AT LEAST ONE OF SAID OPPOSITELY FACING END PORTION, (C) FORMING A BLANK BY SUPERPOSING SAID STACK ON SAID COMPOSITE WITH SAID UNCOATED STRIPS OF SAID LAYERS IN CONTACT WITH SAID COMPOSITE, (D) FORMING AN INTEGRATED UNITARY STRUCTURE BY PRESSURE WELDING SAID SHEETS OF SAID COMPOSITE TOGETHER EXCEPT IN THE AREA OF SAID PATTERN OF WELD PREVENTING MATERIAL AND SIMULTANEOUSLY PRESSURE WELDING SAID STACK TO SAID COMPOSITE IN THE AREAS OF SAID UNCOATED STRIPS, (E) INFLATING THE UNJOINED PORTIONS OF SAID COMPOSITE BY INJECTING THEREINTO A FLUID UNDER PRESSURE THEREBY FORMING INTERIOR HOLLOW PASSEGEWAYS, AND (F) RAISING THE UNJOINED PORTIONS OF SAID LAYERS THEREBY PROVIDING INTEGRAL ERECT FINS OVERLYING SAID HOLLOW PASSAGEWAYS.