ALEXANDRIA, Va., Oct. 21 -- United States Patent no. 12,767,452, issued on Oct. 20, was assigned to Daifuku Co. Ltd. (Osaka, Japan).

"Conveyance device" was invented by Ryo Nakagawa (Shiga, Japan) and Jun Tanaka (Shiga, Japan).

According to the abstract* released by the U.S. Patent & Trademark Office: "A conveyance device includes a traveling vehicle, a mast, a raising and lowering section, and a control section. The traveling vehicle includes a wheel, a motor which drives the wheel, and a slippage detection section which detects slippage at the wheel. In a case where two or more slippage detection sections out of the slippage detection sections detect, at least in a state where the traveling vehicle is accelerated, slippage of not less t...