A propeller. The blades of the propeller are characterized by a blade center axis which corresponds to a generator line of a cone to which the blade, or blade thrust surface, conforms. The propeller hub is fixed to the blade at the root, in line with the blade center axis, such that the hub axis and blade center axis lie in the same plane, and the leading edge of the blade is positioned forward (referring to the upstream direction of movement caused by the propeller) of the trailing edge of the blade.

A propeller. The blades of the propeller are characterized by a blade center axis which corresponds to a generator line of a cone to which the blade, or blade thrust surface, conforms. The propeller hub is fixed to the blade at the root, in line with the blade center axis, such that the hub axis and blade center axis lie in the same plane, and the leading edge of the blade is positioned forward (referring to the upstream direction of movement caused by the propeller) of the trailing edge of the blade.

An underwater motive device includes a rear main housing including two opposite handle bar elements on two sides respectively, and longitudinal rear joining projections on an inner surface; a power mechanism in the rear main housing; a propeller driven by a driving shaft of the power mechanism; a bridging housing including a battery compartment, a forward joining member, a shoulder abutted the forward joining member, and a rear joining member; a hollow intermediate housing including two opposite handle bar members on two sides respectively, the handle bar members joined the handle bar elements, longitudinal front joining projections on an inner surface, and an internal annular limit element at a front end; and a front cone including a rear opening and a structure on an inner surface for securing to the forward joining member of the bridging housing.

An underwater motive device includes a rear main housing including two opposite handle bar elements on two sides respectively, and longitudinal rear joining projections on an inner surface; a power mechanism in the rear main housing; a propeller driven by a driving shaft of the power mechanism; a bridging housing including a battery compartment, a forward joining member, a shoulder abutted the forward joining member, and a rear joining member; a hollow intermediate housing including two opposite handle bar members on two sides respectively, the handle bar members joined the handle bar elements, longitudinal front joining projections on an inner surface, and an internal annular limit element at a front end; and a front cone including a rear opening and a structure on an inner surface for securing to the forward joining member of the bridging housing.

The present invention involves a method for manufacturing a blade (1) for a propeller, which blade (1) has a leading edge (2) and a trailing edge, the method comprising the steps of: forming a conduit in the blade (1), making a plurality of holes (7) through which the conduit (6) communicates with the exterior of the blade (1), and providing a blade blank having an edge part receiving surface (4) extending along at least a major part of the leading edge (2) of the blade (1) to be manufactured, wherein forming a conduit (6) comprises building up an edge part (3) onto the edge part receiving surface (4) by a wire-based additive manufacturing process, wherein the additive manufacturing process is adapted to form the conduit (6) at least partly delimited by the edge part (3) and extending along the leading edge (2) of the blade (1) to be manufactured.

A blade member includes a leading edge, a trailing edge, and a blade body extending therebetween. The blade member also includes a dovetail, a transition region, and a transition relief. The dovetail includes a dovetail chord line extending between an axially forward face of the dovetail and an axially aft face of the dovetail. The dovetail chord line has a dovetail chord length. The transition region is formed between the blade body and the dovetail. The blade body and the transition region form a blade body transition chord line at the interface of the blade body and the transition region which has a blade body transition chord length. The transition relief includes a geometric relief in at least one of a forward and an aft end of the transition region and the dovetail. The dovetail chord length is less than the blade body transition chord length.

A blade member includes a leading edge, a trailing edge, and a blade body extending therebetween. The blade member also includes a dovetail, a transition region, and a transition relief. The dovetail includes a dovetail chord line extending between an axially forward face of the dovetail and an axially aft face of the dovetail. The dovetail chord line has a dovetail chord length. The transition region is formed between the blade body and the dovetail. The blade body and the transition region form a blade body transition chord line at the interface of the blade body and the transition region which has a blade body transition chord length. The transition relief includes a geometric relief in at least one of a forward and an aft end of the transition region and the dovetail. The dovetail chord length is less than the blade body transition chord length.

A peller device with a flap is an apparatus used to enhance the capabilities and efficiency of water circulation and aeration systems. The apparatus is configured to act as both a propeller and an impeller as necessary for a particular water circulation requirement. A flap is an addition to the blade tip which propels a fluid by pushing against the fluid, thus enabling the peller to function as a propeller. In addition, the flap facilitates the generation of a sucking force so the peller can also function efficiently as an impeller. The peller assembly can be encased in circular housings having a vertical axis in which the peller assembly is mounted for rotation on the central axis of the housing. The peller assembly is formed with a hub and a plurality of blades symmetrically positioned around the hub. The flap of the apparatus is attached to the base of the peller assembly.

A peller device with a flap is an apparatus used to enhance the capabilities and efficiency of water circulation and aeration systems. The apparatus is configured to act as both a propeller and an impeller as necessary for a particular water circulation requirement. A flap is an addition to the blade tip which propels a fluid by pushing against the fluid, thus enabling the peller to function as a propeller. In addition, the flap facilitates the generation of a sucking force so the peller can also function efficiently as an impeller. The peller assembly can be encased in circular housings having a vertical axis in which the peller assembly is mounted for rotation on the central axis of the housing. The peller assembly is formed with a hub and a plurality of blades symmetrically positioned around the hub. The flap of the apparatus is attached to the base of the peller assembly.

A method of making a propeller includes forming the propeller to have blades coupled to an outer hub, the outer hub coupled to an inner hub via ribs, and the inner hub configured to be coupled to the marine vessel. The ribs each have first and second ends with a midpoint therebetween, an inner end and an outer end that define a width therebetween, and a leading surface and a trailing surface that define a thickness therebetween. The ribs are tapered such that the thickness is greater at the midpoint than at least at one of the first end and the second end, and scalloped such that the width is greater at the midpoint than at least at one of the first end and the second end. Each of the ribs is coupled to the outer hub in radial alignment with one of the blades.