Abstract: Methods and systems for controlling windmilling in an engine are described. An electric starter motor is coupled to the engine, a circuit element is coupled to the electric starter engine and to a DC signal source, and a control system coupled to the engine and to the circuit element. The control system is configured for: determining whether the engine is in a windmilling state; when the engine is in a windmilling state, commanding the circuit element to apply a DC signal to the electric starter motor; and modulating the DC signal applied to the electric starter motor to control a level of rotational motion of the engine.

Abstract: A system for providing marine propulsion is provided including an input shaft driven by a prime mover, a pinion gear coupled to the input shaft, a plurality of planet gears coupled to the pinion gear, a planet carrier having the plurality of planet gears rotationally mounted thereto, and a ring gear surrounding the planet gears and coupled thereto. The planet carrier and ring gear are coupled to internal and external output shafts that are coaxially aligned, which are coupled to aft and forward propulsor elements. The ring gear and planet carrier rotate in opposite directions to provide contra-rotating forward and aft propulsor elements. The ring gear and planet gear are each coupled to rotation altering devices that, when at least one is activated, the rotation of both the planet carrier and ring gear will be altered, thereby altering the rotation of the propulsor elements.

Abstract: The invention relates to a method for improving the propulsion efficiency of vessels. The improvement is obtained by utilizing wave induced variations in propeller inflow, i.e. the speed of water flowing towards the propeller. The wave induced water speed variation is used to calculate the propeller speed in a way so that the propeller speed is optimal with respect to the total propulsion efficiency. The optimal propeller speed is determined by solving an optimization problem formulated as the maximization of the ratio of energy delivered by the propeller and the energy delivered to the propeller. The method may be used for vessels with one or more propellers.

Abstract: A control system is provided which allows the operator of a marine vessel to select a transmission position (e.g. forward, neutral, or reverse) and an engine speed in the event that a throttle lever malfunctions. By providing messages to the operator on an annunciator and receiving selections from the operator on a plurality of push button switches, a microprocessor selects gear positions and engine operating speed in response to commands received from the operator.

Abstract: The invention discloses an apparatus for reducing maneuverability of a moving ship. The apparatus comprises a propeller fouling element, mountable upon the bow of a second ship. The proper fouling element is deployable towards a propeller of a moving ship. The invention further discloses a rudder engaging component. In one embodiment, the rudder engaging component is U-shaped for accepting a rudder within. The invention also provides a method for reducing the maneuverability of a moving ship, by providing the rudder engaging component and/or the propeller fouling element. The rudder engaging component, when present, is advanced to engage and surround the rudder of the ship. The propeller fouling element is advanced towards a propeller of a ship until it contacts the propeller; thereby reducing the maneuverability of said ship.

Abstract: A self-contained marine reversing gear assembly is provided with a locking device for an internal combustion engine in which introduction of the working oil from the lubricating oil circuit is unnecessary. The locking device includes an input shaft driven by an internal combustion engine; an output shaft connected to a propeller shaft; a hydraulic pump driven by the input shaft; a hydraulic forward and reverse clutch; a directional control valve for switching the forward and reverse clutch by the supply of working oil from the hydraulic pump; and a locking device provided with a locking mechanism member for locking the output shaft. The locking device includes a hydraulic actuator for unlocking the output shaft by operating on the locking mechanism member due to the supply of working oil from the hydraulic pump.

Abstract: The present invention relates to a propeller drive arrangement for vessels used in water-borne traffic, and specifically to a propeller drive arrangement containing a propulsion unit, and to such an arrangement, which contains a propulsion unit, which is turnable relative the hull of the vessel. Particularly the present invention relates to a system and a method for braking a motor of a propulsion unit. The solution for braking the propulsion unit according to the present invention is based on short-circuiting a permanently magnetized motor.

Abstract: A housing for an outdrive is installed with a replaceable tower support for a ball bearing race through which the drive shaft rotates. When the bearing race becomes worn, rather than replacing the entire housing and installing a new bearing race, only the tower support and worn bearing race is removed and replaced, which represents a considerable cost saving.

Abstract: A housing for an outdrive is installed with a replaceable tower support for a ball bearing race through which the drive shaft rotates. When the bearing race becomes worn, rather than replacing the entire housing and installing a new bearing race, only the tower support and worn bearing race is removed and replaced, which represents a considerable cost saving.

Abstract: A shiftable disk clutch or disk brake having two clutch parts which are rotatable relative to one another about a theoretical axis of rotation. One of the clutch parts has at least one rigid pressure disk which is connected with the clutch part so as to be fixed against movement and rigid. The other clutch part has at least two friction disks which are stiff in the circumferential direction and axially flexible in the manner of a diaphragm and are connected with this other clutch part so as to be fixed with respect to movement and rigid and are arranged on both sides of the pressure disk.

Abstract: A shiftable disk clutch or disk brake having two clutch parts which are rotatable relative to one another about a theoretical axis of rotation. Each of the two clutch parts has at least one clutch disk which is stiff against rotation and is rigidly connected with the clutch part so as to be fixed against movement in every direction. A remotely actuatable pressure supply is divided into at least two separate pressure systems, each of which is, by itself, capable of coupling or separating the clutch disks.

Abstract: A multi-propeller drive system having a single input shaft for connection an engine system, a differential gear assembly for dividing the driving force from the input drive shaft between a pair of output shafts and a pair of laterally spaced propellers driven by the output shafts of the differential gear assembly. The differential gear assembly operates in a manner wherein one output shaft, if required, is permitted to revolve at a different rate than the other output shaft. A pair of brake mechanisms acting on the output shafts of the differential gear assembly enable an operator to control the rotational speed of the respective propellers without modifying the engine speed or transmission settings.

Abstract: A block structure of a generally trapezoidal configuration is interposed between a cavitation plate and propeller of a marine engine's lower unit to effect abutment of the propeller permitting loosening and removal of the associated propeller retaining nut member.

Abstract: A personal watercraft, such as a jet ski, is equipped with a hull, an engine and propulsion and a ride plate assembly attached to the bottom section of the hull. The ride plate assembly includes a fixed plate and a lower plate or flap hingedly mounted to the fixed plate to occupy continuously adjustable varying angular positions relative to the fixed plate. A manually operated control mechanism, controlled by an operator, adjusts the angular positioning of the flap within a predetermined range. It is an important characteristic of the continuously adjustable flap that within the range in which its angular positioning relative to the fixed plate and to the water can be changed, an initial and moderate change in angular positioning results in more hydrodynamic lift to act on the watercraft, and therefore in increased speed of the watercraft. However, beyond a certain value, further deflection of the flap results in significant braking action.

Abstract: An improved device for blocking the rotation of marine propellers on lower units of outboards or out-drives is described. The blocking unit has a fixed part and a movable clamp. The fixed part is held by the movable clamp against the under side of the anti-cavitation plate of the lower unit and has a height sufficient to extend down into the propeller rotation circle. When torque is applied to the propeller retaining nut a propeller blade engages the side or bottom of the fixed part and the propeller is prevented from rotating. The blocking unit has an enriching flange and central and transverse webs to provide a low stress design so that it may be fabricated of plastic.

Abstract: A fluid coupling is provided in a marine drive between the engine and the propulsion unit. The fluid coupling includes a fluid pump adapted to be driven by the crankshaft of the engine, and a turbine adapted to be driven by the fluid pump. A series of reactor vanes is provided in the fluid coupling. The reactor vanes are adapted to be driven in a direction opposite the direction of rotation of the fluid pump. The turbine and the reactor vanes are connected to shafts which extend from the fluid coupling to a transmission housing. Each shaft is provided with a gear and a brake disc. An output shaft extends from the transmission housing, and includes a pair of freely rotatable gears engageable with the gears on the reactor shaft and the turbine shaft. Clutch mechanisms are provided on the freely rotatable output shaft gears for selectively engaging the reactor shaft gear and the turbine shaft gear to provide rotation of the output shaft in response to rotation of the reactor shaft and turbine shaft gears.

Abstract: A water borne craft includes a smooth rounded elongate sailboard type hull of little depth. The hull tapers down in width and in depth from its middle towards its ends and has smooth upper and lower surfaces. A cockpit extends downwardly into the hull from its upper surface to provide a craft usable in canoe mode. The craft also includes at least one removable reversible insert which fits snugly in two modes into the cockpit. The upper surface of the insert in one mode, being a paddle-ski mode, has recesses to accommodate the buttocks and feet of a paddle skier when the craft is used in the paddle ski mode. The opposite surface of the insert is uppermost in the other mode, being the sailboard mode. The opposite surface has structure for mounting a mast so that the craft can be used as a sailboard in this mode.

Abstract: A stop device for application to an outboard marine engine to retain the propeller against rotation while the prop nut is being tightened or loosened. The device is T-shaped and includes side wings and a vertical leg. The wings have slots which permit the device to be slipped onto a tail plate located above the propeller. The leg extends downwardly between the blades of the propeller and engages the blades to prevent propeller rotation.

Abstract: A propeller shaft immobilizer having a substantially hollow, open ended rectangular lower base portion fixedly mounted to the floor portion of a boat. An upper support base portion is slidably mounted on the lower base portion to allow vertical movement of the upper base portion. Upper and lower engaging surfaces are movably mounted on the upper base portion and movable by hydraulic power to frictionally engage the propeller shaft to be immobilized.

Abstract: An improved control system is disclosed for air actuated ahead and astern clutches, an engine speed governor, and a propeller shaft brake of a marine propulsion system. The control is actuated by a throttle lever which is moved from a neutral position to select a direction of travel. The degree of movement of the throttle lever from neutral is representative of the desired speed in the selected direction. The improved control engages the brake when the throttle lever is moved from an ahead to an astern direction at medium or high forward speeds. When such a change is commanded, a pair of serially connected brake valves are piloted to connect the brake to a source of air under pressure. One of the brake valves is piloted by an accumulated speed pressure signal indicating an ahead speed greater than a predetermined minimum and the other valve is piloted by the throttle signal commanding astern direction.

Abstract: A marine propulsion system for a water craft comprises a relatively large engine or power plant and a power transmission including an output shaft for driving the propeller. The power transmission includes forward and reverse shafts, gear trains between these shafts and the output shaft, and clutches for the forward and reverse shafts. A shaft brake is provided to stop rotation of the output shaft for the propeller which minimizes damaging shocks to the propulsion system which sometimes occur during maneuvering operations. The brake is located concentrically with the forward shaft of the power transmission and is effective to brake the propeller shaft through interconnecting gears when both clutches are disengaged.

Abstract: An auxiliary engine propeller shaft locking device for sail boats and the like comprising, a base having an upper lock housing and a lower shaft housing; the housings being integral and in substantially abutting relation with each other. The shaft housing includes a rotatable propeller shaft disc mounted thereon having an inner and outer surface. The housings have front and back surfaces, with the shaft disc mounted on the shaft housing front surface, and the lock housing front surface being above the shaft housing front surface. The disc outer surface is below the plane of the front lock housing surface and the disc inner surface is above the plane of the shaft housing front surface to provide rotating clearance for the disc. The shaft disc has a width less than the width of the shaft housing to provide rotating clearance for the disc. The lock housing includes a locking pin and a shot pin for the locking pin, and the disc includes locking pin engaging means.

Abstract: A low noise level, rapidly reversible propulsion system for a submarine or other vessel comprises a non-reversible adjustable speed prime mover, a reversible drive mechanism driven by the prime mover and including a fluid-cooled torque converter and speed reduction apparatus, an energy-dissipating load selectively connectable to the reversible drive mechanism, and a propeller driven by the reversible drive mechanism.