(under subclass 650) Apparatus in which a part of the apparatus shifts its position relative to an adjacent part without the intervention of a human operator, and in response to a transient condition in which a part of the apparatus would be subjected to undesirable stress (e.g., when a lump, clod or rock is encountered in otherwise easily disintegratable material) if shifting did not occur.
(1) Note. Shifting of position which occurs in order to take up the shock of starting is not included under this definition. Such devices are classified on other features.
