Patent ID: 8061460

Claim:
A stair climbing device comprising at least one climbing element which can be moved on a circular path so that the element can get in contact with a next step of a stair and lift or lower the stair climbing device on the next step, said stair climbing device comprising: a drive motor for providing a driving force for moving the at least one climbing element on the circular path, wherein the at least one climbing element is mounted on eccentric arms, wherein the movement of the at least one climbing element on the circular path is carried out with a non-constant rotational speed, wherein a gear transmission assembly is provided between the drive motor and the at least one climbing element, said gear transmission assembly is adapted to cyclically vary the rotational speed of the at least one climbing element with respect to the rotational speed of the drive motor, and wherein the at least one climbing element is implemented as a running wheel mounted on at least one of said eccentric arms.