This application describes clutch mechanisms for use in a steering control system, e.g., a steering control system used to steer a trolling motor for a boat. Such clutch mechanisms can reduce and avoid damage to the steering control system (e.g., a steering motor) when the system is subjected to unusually large impact loads (e.g., when the trolling motor or boat contacts an obstruction). The clutches described in this application can be used to decouple the steering control system from a steering shaft (or other drive mechanism) upon application of a large impact load, thus reducing damage to and increasing the lifespan of such system. In some cases, the clutch is a ball and spring mechanism. In other cases, the clutch is a slip tooth mechanism.

This application describes clutch mechanisms for use in a steering control system, e.g., a steering control system used to steer a trolling motor for a boat. Such clutch mechanisms can reduce and avoid damage to the steering control system (e.g., a steering motor) when the system is subjected to unusually large impact loads (e.g., when the trolling motor or boat contacts an obstruction). The clutches described in this application can be used to decouple the steering control system from a steering shaft (or other drive mechanism) upon application of a large impact load, thus reducing damage to and increasing the lifespan of such system. In some cases, the clutch is a ball and spring mechanism. In other cases, the clutch is a slip tooth mechanism.

A propeller for a water vehicle is provided, comprising a hub and at least two blades, said blades extending outwards from the hub in the radial direction, and the propeller having a uniform blade distribution. The problem addressed by the invention is to provide a propeller for a water vehicle which allows unwanted generation of noise to be efficiently reduced or avoided. According to the invention, the angular distance between the blade tips of two consecutive blades of the propeller varies in relation to the angular distance between the blade tips of two other consecutive blades.

A propeller for a water vehicle is provided, comprising a hub and at least two blades, said blades extending outwards from the hub in the radial direction, and the propeller having a uniform blade distribution. The problem addressed by the invention is to provide a propeller for a water vehicle which allows unwanted generation of noise to be efficiently reduced or avoided. According to the invention, the angular distance between the blade tips of two consecutive blades of the propeller varies in relation to the angular distance between the blade tips of two other consecutive blades.

A drive device for a vessel includes an electric motor, driving a rotatable drive shaft; an elongate drive device housing, encapsulating the electric motor and the drive shaft; and a propeller, detachably mounted to the rotatable drive shaft. The drive device housing has an upper connection device. The upper connection device is symmetrical about a transverse axis, enabling the drive device housing to be mounted to a structure onboard the vessel in either of two longitudinal directions. The drive device and the hull of the vessel are separated from each other by using an isolation plate with a central isolation sleeve. The electric motor drives the drive shaft via an interconnected gear device encapsulated in the drive device housing or integrated as a part of the drive device housing and are arranged pivotably with respect to the tilt device housing.

A drive device for a vessel includes an electric motor, driving a rotatable drive shaft; an elongate drive device housing, encapsulating the electric motor and the drive shaft; and a propeller, detachably mounted to the rotatable drive shaft. The drive device housing has an upper connection device. The upper connection device is symmetrical about a transverse axis, enabling the drive device housing to be mounted to a structure onboard the vessel in either of two longitudinal directions. The drive device and the hull of the vessel are separated from each other by using an isolation plate with a central isolation sleeve. The electric motor drives the drive shaft via an interconnected gear device encapsulated in the drive device housing or integrated as a part of the drive device housing and are arranged pivotably with respect to the tilt device housing.

The present invention provides a hetero-stiffness robotic device with a central body portion having a head end and a tail end. A rigid rotatable head propeller extends from the head end while a flexible rotatable tail propeller extends from the tail end. A head motor positioned in the central body portion rotates the rigid rotatable head propeller and a tail motor positioned in the central body portion rotates the flexible rotatable tail propeller. A controller independently controls a rotational speed of the head motor and the tail motor. The head and tail propellers may have helical shapes. The hetero-stiffness propulsion gives the robotic device a high level of environmental adaptivity over a wide range of viscosities. The device demonstrates advantages in linearity, straightness, bi-directional locomotion ability, and efficiency, which provides a critical competence for moving in low Reynolds number environments.

The present invention provides a hetero-stiffness robotic device with a central body portion having a head end and a tail end. A rigid rotatable head propeller extends from the head end while a flexible rotatable tail propeller extends from the tail end. A head motor positioned in the central body portion rotates the rigid rotatable head propeller and a tail motor positioned in the central body portion rotates the flexible rotatable tail propeller. A controller independently controls a rotational speed of the head motor and the tail motor. The head and tail propellers may have helical shapes. The hetero-stiffness propulsion gives the robotic device a high level of environmental adaptivity over a wide range of viscosities. The device demonstrates advantages in linearity, straightness, bi-directional locomotion ability, and efficiency, which provides a critical competence for moving in low Reynolds number environments.

An outboard motor includes: an outboard motor body including a propeller driven by an internal combustion engine; a mounting portion configured to mount the outboard motor body to a hull so as to be movable relative to the hull; and an operation mechanism provided between the outboard motor body and the mounting portion and configured to adjust a relative position of the outboard motor body with respect to the hull. The operation mechanism is a link-type operation mechanism including a hydraulic cylinder as an actuator.

An outboard motor includes: an outboard motor body including a propeller driven by an internal combustion engine; a mounting portion configured to mount the outboard motor body to a hull so as to be movable relative to the hull; and an operation mechanism provided between the outboard motor body and the mounting portion and configured to adjust a relative position of the outboard motor body with respect to the hull. The operation mechanism is a link-type operation mechanism including a hydraulic cylinder as an actuator.