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:
Oct. 01, 1991
Filed:
Aug. 28, 1990
Applicant:
Inventors:
Shunroku Sukumoda, Aizuwakamatsu, JP;
Seizo Masukawa, Aizuwakamatsu, JP;
Haruo Kohno, Aizuwakamatsu, JP;
Assignee:
501 Mitsubishi Shindoh Co., Ltd., Fukushima, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F28F / ;
U.S. Cl.
CPC ...
165133 ; 165179 ; 165183 ; 165184 ; 138 38 ;
Abstract
A heat transfer tube having an inner surface in which are formed primary grooves and secondary grooves. The primary grooves parallel to one another, extending at an angle to the longitudinal direction of the heat transfer tube and secondary grooves parallel to one another, extending an angle to the primary grooves. At the intersections of the primary and secondary grooves is formed a series of pear-shaped grooves whose inner opening dimension is smaller than the dimension of the bottom of the pear-shaped groove.