A propeller apparatus of a ship propulsion machine includes a tubular member inserted into an insertion hole so as to be movable in a circumferential direction with respect to a hub. First concave portions arranged in a circumferential direction are formed in an outer peripheral surface of the tubular member. Second concave portions arranged in the circumferential direction so as to respectively face the first concave portions are formed in an inner peripheral surface of the insertion hole. Each of the elastic bodies has a spherical or columnar shape, a first portion of each of the elastic bodies is disposed in each of the first concave portions, a second portion of each of the elastic bodies is disposed in each of the second concave portions, and the elastic bodies are rotatably held between the first concave portions and the second concave portions facing each other.

Disclosed herein is an inventive dual propeller assembly that can be manually or automatively assembled and includes a leading propeller, a torsion bushing, a thrust washer, a drive sleeve, and a trailing propeller. The propellers were coupled with an alignment system that did not require welding of the two propellers. The leading propeller includes a cylindrical hub and a plurality of blades that extend from an outer surface of the cylindrical hub. The trailing propeller includes a first cylindrical hub having a plurality of grooves, a second cylindrical hub having a cylindrical mount ring, and a conical profile formed between the first cylindrical hub and the second cylindrical hub. The outer surface of the first cylindrical hub is designed to mate with the inner surface of the cylindrical hub of the leading propeller. The trailing propeller is secured and aligned coaxially with the leading propeller. The trailing propeller can be effectively and consistently used with existing propellers.

Disclosed herein is an inventive dual propeller assembly that can be manually or automatively assembled and includes a leading propeller, a torsion bushing, a thrust washer, a drive sleeve, and a trailing propeller. The propellers were coupled with an alignment system that did not require welding of the two propellers. The leading propeller includes a cylindrical hub and a plurality of blades that extend from an outer surface of the cylindrical hub. The trailing propeller includes a first cylindrical hub having a plurality of grooves, a second cylindrical hub having a cylindrical mount ring, and a conical profile formed between the first cylindrical hub and the second cylindrical hub. The outer surface of the first cylindrical hub is designed to mate with the inner surface of the cylindrical hub of the leading propeller. The trailing propeller is secured and aligned coaxially with the leading propeller. The trailing propeller can be effectively and consistently used with existing propellers.

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.

One embodiment of submerged superventilated blades (101) that provide hydrodynamic force to a vessel or aircraft (117) that can lift it above the surface of the water (106) at high speed by creating thrust with a wetted high pressure surface (111), the low pressure surface (112) being covered with a gas filled void in the liquid, thus preventing sudden loss of lift as speed increases due to cavitation or surface venting. Other embodiments are described and shown.

One embodiment of submerged superventilated blades (101) that provide hydrodynamic force to a vessel or aircraft (117) that can lift it above the surface of the water (106) at high speed by creating thrust with a wetted high pressure surface (111), the low pressure surface (112) being covered with a gas filled void in the liquid, thus preventing sudden loss of lift as speed increases due to cavitation or surface venting. Other embodiments are described and shown.

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.

The invention comprises an improved nut for securing a propeller to a drive shaft of a vehicle engine. The invention further comprises a nut that may be securely fastened to the end of the drive shaft of a trolling motor engine without the use of separate tools, such as wrenches or drivers. The invention even further comprises a nut with an exterior portion and a shaft portion that communicates along an axis of the drive shaft of a marine engine against the propeller assembly, the shaft portion having elastomeric materials to interface with the propeller assembly and at least one channel which together absorb vibration, heat and sound from the propeller assembly.

The invention comprises an improved nut for securing a propeller to a drive shaft of a vehicle engine. The invention further comprises a nut that may be securely fastened to the end of the drive shaft of a trolling motor engine without the use of separate tools, such as wrenches or drivers. The invention even further comprises a nut with an exterior portion and a shaft portion that communicates along an axis of the drive shaft of a marine engine against the propeller assembly, the shaft portion having elastomeric materials to interface with the propeller assembly and at least one channel which together absorb vibration, heat and sound from the propeller assembly.