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:
Dec. 02, 2025
Filed:
Dec. 05, 2023
Rinnai Corporation, Aichi, JP;
Hidenao Negi, Aichi, JP;
Toshimitsu Nagasaka, Aichi, JP;
RINNAI CORPORATION, Aichi, JP;
Abstract
In a heat exchanger, a respective meander passagein each of two stages connecting heat absorbing tubesdivided into the two stages and arranged in a flow direction of a combustion gas in an inside of a casingfrom one side to the other side in a Y-axis direction is constituted, and both a heat absorbing tubeof #at an upstream end of the meander passagein a first stage and a heat absorbing tubeof #at a downstream end of the meander passagein a second stage are made to be positioned at the one side in the Y-axis direction, notches are provided with each heat absorbing finat portions positioned at a more upstream side in the flow direction of the combustion gas than each heat absorbing tubeof the meander passagein the second stage, and first notchescorresponding to the heat absorbing tubeat a downstream end of the meander passagein the second passage are formed larger than second notchescorresponding to each heat absorbing tubeother than the heat absorbing tubeof #at the downstream end.