It is a coupling realizing efficient power transmission by a compact design for power transmission by a different shaft center that was conventionally composed of a spline shaft or universal joint. SCHMIDT coupling is a coupling for a different shaft center utilizing a crank motion of link. Motive power inputted on one end disc is transmitted to the other end disc through a link and center disc. Shaft center displacement is determined by the link length. This coupling enables parallel displacement of shaft center during rotation as well as power transmission by a different shaft center