ALEXANDRIA, Va., Feb. 26 -- United States Patent no. 12,233,931, issued on Feb. 25, was assigned to WONDERLAND SWITZERLAND AG (Steinhausen, Switzerland).
"Vehicle frame and baby stroller" was invented by Jian-Qun Li (Guangdong, China).
According to the abstract* released by the U.S. Patent & Trademark Office: "A vehicle frame applied to a baby stroller includes a first tube, a second tube, a third tube and a foldable unit. The second tube is pivoted to the first tube. The third tube is pivoted to the second tube. The foldable unit includes a fourth tube. An end of the fourth tube is pivoted to the first tube, and the other end of the fourth tube is pivoted to the third tube. A linkage mechanism is formed by the first tube, the second tube...