Abstract: The invention relates to a hand-lever control for motor and sport boats with a hand lever having a handle and guided in at least one function plane for controlling the engine. In order to facilitate maneuvering for the pilot, the hand lever or its handle is pivotal about the axis of the hand lever in two directions against a spring force and at least one sensor detecting this rotation is provided whose output controls a steering system.

Abstract: A variable-pitch boat propeller has a hub rotatable about a hub axis, a plurality of vanes rotatable on the hub and extending generally radially of the hub axis, and an adjustment element rotatable on the hub about the hub axis and connected to the vanes for pivoting the vanes on the hub. An adjustment knob is pivotal on the hub about the hub axis and interengaging formations on the knob and hub limit angular displacement of the knob on the hub between a pair of end positions so that a limited range of adjustment of the vanes is possible with the knob. The interengaging formations include an axially open groove having a pair of ends constituting abutments and an axially projecting screw head and rotationally fixed relative to the hub and received in the groove. The groove is formed in the knob and the screw head is carried on a yoke rotationally coupled to the hub. The groove is arcuate, centered on the hub axis, and has an arc length of substantially less than 360°.

Abstract: A variable-pitch boat propeller has a hub centered on and rotatable about a hub axis and formed with a radially out-wardly open pocket having a predetermined inside diameter and centered on a vane axis extending generally radially of the hub axis and a mounting plate rotatable in the pocket about the vane axis and having an outer face. A ring fixed in the pocket and having inner and outer peripheries bears radially inward of the hub axis on the mounting plate. An inner seal is provided between the inner ring periphery and the plate and an outer seal between the outer ring periphery and the pocket. A vane extending along the vane axis has a base of an outside diameter smaller than the inside diameter of the pocket and fitting in the pocket on the face of the plate. A screw or the like releasably secures the vane base to the plate face, and mechanism pivots the plate in the pocket about the vane axis.

Abstract: A boat propeller has a housing adapted to be fixed to a boat, a hub rotatable about a main axis on the housing, a plurality of generally radially projecting vanes pivotable on the hub, and an operating core shaft coaxially received in the hub, rotatable about the main axis but axially nondisplaceable relative thereto, and having a rear end projecting axially from the hub and a front end. A yoke is fixed to the rear core-shaft end and respective rods fixed to the yoke are connected to the vanes for pivoting the vanes on angular movement of the core shaft about the main axis. A cylinder axially fixed in the housing at the front core-shaft end holds an axially displaceable piston. A nut element having a nonbinding internal screwthread is threaded on a screw element. One of the elements is axially coupled to the piston and the other of the elements is axially coupled to the core-shaft front end.

Abstract: A boat drive having a variable-speed engine connected through a clutch to a variable-pitch propeller has a control having a housing and a guide on the housing defining a central crosswise track having a travel end and a start end, forward and backward travel tracks extending from the travel end, and a forward start track extending from the start end. A lever pivoted on the housing is movable in the tracks of the guide. A pitch controller connected to the propeller includes a position detector operable by the lever when in the travel end and travel tracks for increasing propeller pitch positively on movement of the lever forward from the travel end in the forward travel track and negatively on movement of the lever backward from the travel end in the backward track and for setting the propeller at 0° pitch when the lever is in the travel end.

Abstract: A boat drive has a housing, a tube shaft rotatable in the housing about a shaft axis and having axially opposite front and rear ends, a hub carried on the shaft rear end, and a plurality of radially projecting vanes pivotal on the hub. An axially shiftable core shaft extending coaxially in the tube shaft has a rear end rearward of the tube-shaft rear end and a front end forward of the tube-shaft front end. Mechanism connecting the core-shaft rear end with the vanes pivots the vanes on the hub on axial displacement of the core shaft. A pair of oppositely directed axial-thrust bearings on the core-shaft front end are contained in and surrounded by a hollow piston having front and rear faces axially flanking the thrust bearings. A cylinder fixed in the housing and surrounding the piston forms with the respective faces thereof front and rear compartments so that pressurization of the front compartment shifts the core shaft rearward and pressurization of the rear compartment shifts the core shaft forward.