Abstract: A hydrojet for ships, intended for use in shallow waters, has a semiaxially bladed impeller with a vertical axis of rotation rotatably arranged in a well-shaped housing. The drive for the impeller is introduced into the housing from the top through a cover plate, and the housing is closed at the bottom by a bottom plate which has a water inlet arranged in the center for axial admission to the impeller and at least one flatly sloped water outlet. A control device in which the water delivered by the impeller is fed to at least one outlet nozzle without conversion of kinetic energy into pressure energy, is arranged between the discharge end of the delivery channels of the impeller and at least one water outlet. The control device forms a ring channel without blading. The water inlet is designed asymmetrically.

Abstract: Propulsion unit for watercraft, with a drive shafting (3) between a drive motor (2) and a propulsive device (1), wherein this propulsion unit with vertical drive shafting is arranged in the shaft-like housing (12) of the hull (14) such that the distance between the motor and the propulsive device is adjustable. The motor (2) acts on the drive shafting (3) via a disengaging coupling (19), and is adjustable in the horizontal plane between two end positions when the coupling (19) is disengaged, wherein the motor (2) and the drive shafting (3) can be coupled with one another in one end position, and the drive shafting (3) with the propulsive device (1) associated with it can be moved past the motor in the other end position of the motor (2).

Abstract: A boat propulsion unit has a propeller which can be withdrawn into a sleeve to a position above the plane of the boat's bottom and enclosed by a cover plate. The water in the closed sleeve can be pumped out, so that the emptied sleeve is accessible for inspection and maintenance operations.

Abstract: A drive unit for a relatively small watercraft has a cylindrical underwater partial housing which carries, at one end, an electric motor to be operated photovoltaically, with which a propeller is arranged, at the other end, in such a way that it is seated on a shaft which is rotatably mounted in parallel relationship to the motor output shaft. The propeller shaft is supported in non-lubricated bearings in a partial housing connected to the cylindrical underwater partial housing. A toothed belt drive, having a toothed belt extending from the motor-side open end of the cylindrical underwater partial housing into the cylindrical underwater partial housing, to the motor shaft, is inserted between the motor output shaft and the propeller shaft.

Abstract: An energy-generating plant including a solar generator, having solar cells, for producing electrical energy. The electrical energy is supplied to a direct current converter, the output power of which may be used to charge an energy storage system, such as batteries. The input resistance of the direct current converter is adapted, such as by a microcomputer, to the maximum power point (MPP) of the solar generator, the MPP being dependent upon the solar insolation and the temperature of the solar cells. At start up of the plant, or when there is a change of power at the output of the direct current converter, a search process is carried out to attain the MPP of the solar generator. The energy storage system may be used to energize an electric motor for driving the propeller of a ship.

Abstract: A speed and direction indicator for ships having at least one rudder propeller, or pump jet, and preferably several such devices for determining the direction of the ship and its speed in the selected direction. An optical display is provided in the area occupied by the ship operator, on which display are shown the angle which is formed between the direction of force and a reference direction, and the strength of the thrust, independently of the operating state of the rudder propeller(s) or the pump jet(s).

Abstract: A drive mechanism particularly for flat-bottomed watercrafts with at least one centrifugal pump or the like producing a water jet, which pump is arranged closely above the intake opening within the watercraft and within an elbow which is pivotal for controlling the watercraft and the blades or the like of which pump are connected by a ring or the like.

Abstract: A watercraft includes two steerable propellers driven by motors, the angular positions of and the thrusts produced by the steerable propellers being controlled by a control system. The control system includes an input device having a frame, a head and a handwheel supported on the frame for independent pivotal movement about a common first axis, and a lever supported on the head for pivotal movement about a second axis normal to the first axis. The head, handwheel and lever are each operatively coupled to a respective input element by a respective gear arrangement. A microcomputer responsive to the input elements is connected through several control devices to the motor and the steerable propellers for effecting the requisite control thereof.

Abstract: A water-jet drive mechanism for driving and controlling a watercraft includes a substantially cylindrical support housing which is supported for rotational movement about a substantially vertical pivot axis in a cylindrical recess in the undersurface of the watercraft, with its undersurface flush with that of the watercraft. A centrifugal water pump is encased in the support housing so that its inlet and its discharge nozzle open through the undersurface of the support housing. The pump drive shaft is inclined and lies in a vertical plane arranged at an angle to the direction of water discharge from the nozzle. A normally open ventilating valve provided in a wall of the pump is closed by the flow of water through the pump.

Abstract: An apparatus for driving and controlling a watercraft or the like having at least one pair of steerable propellers, the steerable propellers of each pair being located substantially symmetrically on opposite sides of the center line of the watercraft, such center line extending through the center of lateral resistance of the watercraft. A control element is provided for carrying out control movements in two degrees of freedom. Each control movement acts for remote control of the steerable propellers through transmitters corresponding respectively to such steerable propellers. Movement of the control element in one degree of freedom effects a rotation about an axis for controlling, through the transmitters, a synchronous pivoting of the servo propellers of each pair. Movement of the control element in the second degree of freedom effects movement of a rack element for controlling, through the same transmitters, an oppositely directed pivoting of the servo propellers relative to one another.

Abstract: A water-jet drive mechanism for driving and controlling a watercraft. A centrifugal water pump is encased in the support housing so that its inlet and its discharge nozzle open through the undersurface of the support housing. The pump drive shaft is inclined and lies in a vertical plane arranged at an angle to the direction of water discharge from the nozzle. A normally open ventilating valve provided in a wall of the pump is closed by the flow of water through the pump.

Abstract: A drive mechanism for ships or the like having at least one main propeller or the like drivable by at least one main motor and further having at least one drivable auxiliary mechanism, for example a maneuvering propeller. An energy producer is drivable by the main motor. A further motor is driven by the energy producer and arranged for driving the drivable auxiliary mechanism. An adjusting mechanism is provided for adjusting energy emitted by the energy producer or absorbed by the further motor. A regulator adjusts the adjusting mechanism to a preselected energy output. The main motor and the auxiliary mechanism are sized such that in the higher part of the speed range of the main motor, the sum of the energy required to drive the propulsion means at that speed and simultaneously drive the auxiliary mechanism at that speed exceed the output available from the main motor.

Abstract: A water-jet drive mechanism for driving of watercraft and including an elbow located in the hull of the watercraft and containing a pump or the like by which water is sucked in at the bottom of the watercraft through a suction passage and is ejected downwardly through an ejector passage. A gas is supplied to the water jet at the ejector passage.

Abstract: A reversing mechanism for steerable propellers on ships wherein the direction of travel of the ship is controlled by the position of the steerable propeller. A selector switch is provided for controlling the direction of travel as well as directions forward and rearward such that when the direction of travel is to be reversed, the steerable propeller will be sequentially disengaged from the propeller driving mechanism and automatically pivoted through 180.degree. to effect a reverse operation without altering the position of the steering control. In other words, the position of the steerable propeller will be altered without altering the position of the steering control when the direction of travel of the ship is to be reversed.

Abstract: A hydro-jet drive for watercraft. A device is provided applicable for mounting in the hull of a boat by which a jet stream can be created and directed in any desired direction for movement of the boat accordingly. There is provided an elbow having an intake portion and a substantially horizontal discharge opening. The elbow is rotatable on an axis of rotation and contains a suitable motor driven impeller. A motor driven device is provided for rotating the elbow about the axis of rotation thereof for effecting discharge in an operator determined direction. The axis of rotation of the impeller is arranged eccentrically with respect to the axis of rotation of the elbow. The device is particularly adaptable for shallow draft vessels.

Abstract: A watercraft having at least a pair of steerable propellers thereon spaced longitudinally along the center of the watercraft from a center of lateral resistance on the watercraft. The steerable propellers are also spaced equidistant from the longitudinal center line and on opposite sides thereof. The propellers are rotatably supported in underwater housings supported for angular movement through 360.degree.. A control device is provided for varying the direction of applied thrust to the watercraft by systematically varying the axes of rotation of the propellers relative to each other, assuming the thrust force for each steerable propeller is of the same magnitude. The magnitude of thrust can be, if desired, varied to provide additional control variations for the watercraft.

Abstract: A steerable propeller arrangement in a watercraft wherein the propeller is mounted in the forward one-half of the hull of the watercraft. The steerable propeller projects downwardly from the bottom portion of the hull and is pivotal about 360.degree.. The propeller is mounted in a downwardly opening cylindrical well in the bottom of the hull and is housed in an inner cylindrical member which is spaced radially inwardly from an outer cylindrical wall defining the well in the hull. The steerable propeller arrangement can be removed from the hull by raising the inner cylindrical member and propeller upwardly into the interior of the watercraft. Thrust blocks are provided between the two cylindrical members to absorb thrust applied by the drivable propeller arrangement.