ALEXANDRIA, Va., April 9 -- United States Patent no. 12,268,820, issued on April 8, was assigned to Hunan Ventmed Medical Technology Co. Ltd. (Shaoyang, China).

"Non-hysteretic oxygen supply respirator system" was invented by Zhe Liu (Shaoyang, China), Lei Zhou (Shaoyang, China), Congneng Tang (Shaoyang, China), Qichang Zheng (Shaoyang, China), Jinping Su (Shaoyang, China) and Zaixin Yuan (Shaoyang, China).

According to the abstract* released by the U.S. Patent & Trademark Office: "The present invention discloses a non-hysteretic oxygen supply respirator system, comprising a respiratory mask, an inhaling pipe, an exhaling pipe, an oxygen supply chamber, an auxiliary oxygen supply pipeline, and a start-stop cylinder for opening and closing...