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:
May. 02, 2000
Filed:
Mar. 12, 1999
Hiroyuki Takahashi, Kanagawa, JP;
Chikara Saeki, Kanagawa, JP;
Kabushiki Kaisha Kobe Seiko Sho, Kobe, JP;
Sanyo Electric Co., Ltd., Moriguchi, JP;
Abstract
A heat exchanger tube includes ribs formed in protrusion on an internal surface of the tube and extending spirally with a suitable distance between adjacent ribs, concavities formed on the external surface of the tube and extending spirally with a suitable distance between adjacent concavities, and a plurality of independent projections formed on the external surface of the tube and laid out spirally. The projections are formed with a recess on their top surfaces in such a way that a portion aligned with the ribs on the internal surface of the tube is lower than a portion aligned with an area between the ribs. Further, the concavities on the external surface of the tube and the ribs on the internal surface of the tube are formed at mutually aligned positions.