Abstract: The invention relates to mechanical engineering, in particular to devices for converting oscillatory motion into unidirectional rotational motion and can be used, for example, in lifting devices, electric power producing devices, machine tools, pumps and transportation means, particularly internal combustion engines. The device comprises a body and input and output axes. The essence of the invention is that the device is provided with an intermediate axis arranged in the body perpendicularly to the input axis, at least two rotation transmitting coupling elements in the form of a freewheel clutch or ratchet clutch rigidly mounted on the output axis so as to be capable of mutually inverse rotational action and at least three interconnected rotation transmitting elements rigidly mounted between the coupling elements so as to be capable likewise of mutually inverse rotational action for transmitting the rotation of the output axis in one direction.