(under subclass 309) Structures in which one of the components, when both are in housed, inoperative or inaccessible position, must be moved before the other can be moved.
SEE OR SEARCH THIS CLASS, SUBCLASS:
216, for doors and exterior walls of movable compartments having marginal extensions or marginal portions which overlap and block movement of two or more housed components, unless and until the door or compartment is moved from closed position.
222, for sequentially movable diverse parts wherein the movement of one part release the latch of another movable part.
