Patent ID: 7229244

Claim:
A fluid flow actuated drive means including: a rotatably mounted impeller which defines a set of circumferentially spaced outer chambers which extend inwardly from openings along a peripheral edge of the impeller and a set of inner chambers which are arranged radially inwards the outer chambers, each outer chamber being connected to a corresponding inner chamber via a passage to facilitate the forming of a Venturi between corresponding inner and outer chambers; a housing which is configured to span the peripheral edge and to inhibit fluid flow out of the openings when the impeller is rotated relative to the housing; an inlet defined in the housing to permit a jet of gas to be directed at a desired angle relative to the openings when they are in alignment with the inlet to rotate the impeller; and an outlet defined in the housing to permit expulsion of the gas from the chambers when the openings pass and are in momentary alignment with the outlet to further encourage rotation of the impeller.