ALEXANDRIA, Va., Dec. 2 -- United States Patent no. 12,487,035, issued on Dec. 2, was assigned to RINNAI Corp. (Aichi, Japan).
"Heat exchanger" was invented by Hidenao Negi (Aichi, Japan) and Toshimitsu Nagasaka (Aichi, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "In a heat exchanger, a respective meander passage 31, 32 in each of two stages connecting heat absorbing tubes 31 divided into the two stages and arranged in a flow direction of a combustion gas in an inside of a casing 1 from one side to the other side in a Y-axis direction is constituted, and both a heat absorbing tube 31 of #11 at an upstream end of the meander passage 31 in a first stage and a heat absorbing tube 31 of #21 at a downstre...