An unmanned aerial vehicle includes a propulsion system including a driving device having a main body, a driving shaft rotatable relative to the main body, and a locking member disposed on the main body. The locking member includes at least one snap-fitting member. The propulsion system also includes a propeller coupled with the driving device, the propeller including a blade base and a blade mounted on the blade base. The at least one snap-fitting member is configured to snap-fit with the propeller. The propulsion system also includes an elastic abutting member sleeve coupled with the driving shaft, a first installation foolproof member disposed on the blade base, and a second installation foolproof member disposed on the locking member.

An unmanned aerial vehicle includes a propulsion system including a driving device having a main body, a driving shaft rotatable relative to the main body, and a locking member disposed on the main body. The locking member includes at least one snap-fitting member. The propulsion system also includes a propeller coupled with the driving device, the propeller including a blade base and a blade mounted on the blade base. The at least one snap-fitting member is configured to snap-fit with the propeller. The propulsion system also includes an elastic abutting member sleeve coupled with the driving shaft, a first installation foolproof member disposed on the blade base, and a second installation foolproof member disposed on the locking member.

The invention relates to a drive system, and method of forming the same, for a craft in water, said drive system comprising a drive means, one or more shafts which are provided in connection with the drive means via one or more gear assemblies and at least one of said shafts having a free end with location means to allow the same to be located with a propeller of the said craft to impart rotational drive to the propeller. The location means are at least partially located within a port in the body of the propeller and intermediate said location means and the walls of the said port there is provided a substantially non-conductive deformable material sleeve which separates the propeller body from the said shaft and retains the propeller body in drive engagement with the location means. The provision of the sleeve allows the electrical isolation of the sleeve and propeller, allows a more robust connection between the propeller and drive means and reduces the impact of vibration on the operation and efficiency of the propeller.

The invention relates to a drive system, and method of forming the same, for a craft in water, said drive system comprising a drive means, one or more shafts which are provided in connection with the drive means via one or more gear assemblies and at least one of said shafts having a free end with location means to allow the same to be located with a propeller of the said craft to impart rotational drive to the propeller. The location means are at least partially located within a port in the body of the propeller and intermediate said location means and the walls of the said port there is provided a substantially non-conductive deformable material sleeve which separates the propeller body from the said shaft and retains the propeller body in drive engagement with the location means. The provision of the sleeve allows the electrical isolation of the sleeve and propeller, allows a more robust connection between the propeller and drive means and reduces the impact of vibration on the operation and efficiency of the propeller.

The present invention relates to a lightweight composite propeller for an outboard motor, wherein the propeller has a separate hub and blades which are easily repaired when damaged, improves fuel efficiency because a lightweight composite material is used therefor, and is easily manufactured in large quantities.

The present invention relates to a lightweight composite propeller for an outboard motor, wherein the propeller has a separate hub and blades which are easily repaired when damaged, improves fuel efficiency because a lightweight composite material is used therefor, and is easily manufactured in large quantities.

The present disclosure relates to the field of outboard engines, particularly to a direct-drive electric outboard engine and an outboard engine system for alleviating the problem of the existing outboard engines, i.e., incapability of simultaneously meeting requirements on rev and torque of different types of ships. The direct-drive electric outboard engine includes an external rotor mechanism and a stator mechanism; wherein the external rotor mechanism includes an external stator and an impeller; the external rotor is located outside the stator mechanism; and the impeller is located outside the external rotor.

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.

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.