(under the class definition) Apparatus in which one or more working members act to form a progression of completely isolated expanding working chambers by a unidirectional movement.
(1) Note. Motors comprising a series of working members or a single working member carried on an endless flexible member and travelling unidirectionally are found here.
SEE OR SEARCH CLASS
415, Rotary Kinetic Fluid Motors or Pumps,
5, for fluid motors of the endless type operated by a
directed or confined fluid flow and see section III of this class definition for a general statement of the line between this Class 91 and Class 415.
416, Fluid Reaction Surfaces (i.e., Impellers), 7+, for one or more working members supported or an endless flexible carrier and reacting with an undirected or unconfined medium fluid flow.
