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:
Apr. 20, 2021
Filed:
Aug. 17, 2018
Han Yong Cho, Yongin-si, KR;
Han Yong Cho, Yongin-si, KR;
Other;
Abstract
A dual pipe includes an outer pipe having a valley/ridge portion on an outer circumferential surface thereof, and an inner pipe having a valley/ridge portion formed on an inner circumferential surface thereof and inserted into the outer pipe. In the dual pipe, the inner pipe and the outer pipe are threadedly engaged with each other. A low pressure refrigerant passes through the inner pipe. In order to secure a passage of a high pressure refrigerant in a space between the outer circumferential surface of the inner pipe and the inner circumferential surface of the outer pipe, a part of the helical valley/ridge portion formed on the outer circumferential surface of the inner pipe is composed of a multiple-helix helical valley/ridge portion.