Abstract: Folding propeller which consists of blades (1) hinged to a hub (7) in such a way that they can turn about 56 degrees from a position at rest, where they are pointing aft, to a working position towards a stop. The identical movements of the blades (1) are achieved by the use of two cog-wheel connections, where each cog-wheel consists of only one tooth. The two connections are arranged side by side but in opposite directions in order to ensure a fixed connection. The tooth faces (10) may be given the shape of an arc of a circle. The propeller blades (1) may be fixed to the hub mechanism by means of pins (2) arranged in the longitudinal axis of the blades (1). The pitch of the blades (1) may then be changed.

Abstract: A fluid pump including a shaft arranged to be rotatably driven by a motor of the like which includes one or more blades pivotally mounted at their inner ends on the shaft so as to be freely pivotal during the rotation of the shaft into an equilibrium angular position throughout an angular range extending in both directions from a 90.degree. position and in an axial plane with respect to the axis of the shaft.

Abstract: A propeller such as a ship's propeller or screw comprises at least one propeller blade, and a propeller drive shaft. The propeller blade is mounted on the propeller drive shaft by employing a hub having a free end secured on the propeller drive shaft. The hub is provided with a central bore in the free end thereof. A pivot axis is defined mounted within the hub and perpendicular to the axis of the drive shaft. The pivot axis comprises a pivot shaft.The blade is pivotally mounted about the inner end of the blade freely about the pivot shaft, the pivot shaft intersecting the longitudinal direction of the blade. Abutment means for the blade are provided for limiting the free pivotal movement of the blade between two extreme positions at either side of the position in which the propeller blade extends substantially perpendicular to the axis of the shaft. The abutment means comprises a pair of abutment members secured in the bore to serve as abutments for the blades.

Abstract: There is disclosed a propeller adapted for driving a vehicle, such as a boat. The propeller comprises a pair of pivotally mounted propeller blades which are adapted to assume an inactive position wherein the blades are substantially aligned with the direction of vehicle movement, and a working position wherein the blades are at an angle with respect to the direction of vehicle movement. A stop means on the propeller limits the forward pivotal movement of the propeller blades to those locations between the inactive position and a stop position wherein the propeller blades each forms an oblique angle with respect to the inactive position so the propeller blades can each assume a working position which is located on either side of a perpendicular position wherein the propeller blades are perpendicularly disposed to the direction of vehicle movement.