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:
Nov. 04, 1997
Filed:
Mar. 18, 1996
Martin Schmidt, Frondenberg, DE;
Ulrich Naumann, Menden, DE;
KM Europa Metal Aktiengesellschaft, Osnabruck, DE;
Abstract
A heat exchanger tube having a smooth outer surface and a textured inner surface. The inner surface is composed of parallel ribs which run at an angle deviating from 90.degree. relative to the longitudinal axis of the exchanger tube. The ribs further have inclined flanks, channels delimited on the sides by the ribs, and depressions formed in the ribs, which may run crosswise at a distance from the bottom of the channels. The depressions are formed so as to follow a sine-shaped progression, in longitudinal cross-section of the ribs, which are provided with a surface micro-roughness and which are rounded on the top. The center longitudinal planes of the depressions are arranged at an angle deviating from 90.degree. relative to the longitudinal axis of the exchanger tube. The opposite flanks of adjacent ribs are connected by means of rounded channel bottoms. The micro-roughness of the rib surfaces is produced by corundum blasting or laser beams.