US Patent 7856871 Wheel for vehicles

A wheel for vehicles includes a rim, a tyre mounted on the rim, and at least one device for energy generation operatively associated with the tyre. The device for energy generation includes a first element that is fixed relative to the rim or to the tyre, and a second element mounted on the first element and free to rotate relative to the first element around a predetermined rotation axis. The second element has a mass centre eccentric to the predetermined rotation axis. The device for energy generation further includes an electric generator having a stator mounted on the first element and a rotor mounted on the second element.