The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 12, 1993
Filed:
Aug. 12, 1991
Lin-Tao Lu, Fort Smith, AR (US);
Ali Shenasa, Fort Smith, AR (US);
Diane M Jakobs, Alma, AR (US);
Gallen W Stokes, Fort Smith, AR (US);
Rheem Manufacturing Company, New York, NY (US);
Abstract
A high efficiency fuel-fired condensing furnace is provided with a compact recuperative heat exchanger structure comprising a metal primary heat exchanger positioned above and operatively connected to the inlet side of a secondary heat exchanger formed from a polyetherimide (PEI) plastic material. The primary heat exchanger is formed from a horizontally spaced series of vertically serpentined metal combustor tubes, and the second heat exchanger if formed from horizontally spaced apart injection molded inlet and outlet collector boxes interconnected by a horizontally spaced series of elongated hollow extruded plate members sealingly secured at their opposite ends to the collector boxes with the side edge-to-side edge widths of the hollow plate members being vertically oriented. The outlet ends of the metal tubes are operatively connected to the plastic inlet collector box. Cross-sectionally along their lengths, the hollow plastic plate members have horizontally flattened portions interdigitated with horizontally enlarged, convexly curved poritons. Various heat transfer-enhancing alternate embodiments of the hollow plate members are disclosed. Additionally disclosed is an alternate embodiment of the plastic secondary heat exchanger in which the inlet collector box is positioned atop the outlet collector box, and the hollow plate members are internally baffled in a manner causing combustion gas exiting the inlet collector box to make two passes through the hollow plate members before entering the outlet collector box.