(under the class definition) Apparatus comprising a working member* including conduit means for conducting a flow of fluid therethrough and wherein either the inlet or outlet to the flow conducting means is on the working member for the intake or discharge of fluid directly to or from the working fluid*.
(1) Note. Impellers having means for modifying the aerodynamic action of the blades thereof by giving motion to the layer of fluid in contact with the blades by an intake or discharge of fluid adjacent the layer (i.e., boundary layer excitation) are here classified.
(2) Note. A mere apertured, looped or foraminous working member wherein the medium fluid flows substantially uninterruptedly through the member is not included under this definition, being properly classifiable in subclasses 227+ or 231 below.
