Abstract: A power transmission device for an outboard motor, comprising a drive shaft, an endless loop flexible drive coupling and a propeller shaft, wherein the endless loop flexible drive coupling operatively connects said drive shaft to said propeller shaft for transferring output power from the drive shaft to the propeller shaft. The power transmission device comprises a first drive shaft, a second drive shaft, a first endless loop flexible drive coupling, a second endless loop flexible drive coupling, a first propeller shaft and a second propeller shaft, wherein the first propeller shaft is connected to the first drive shaft through the first endless loop flexible drive coupling to rotate the first propeller shaft in a first direction, and wherein the second propeller shaft is connected to the second drive shaft through the second endless loop flexible drive coupling to rotate the second propeller shaft in a second direction opposite to the first direction.

Abstract: An outdrive for a marine vessel, such as a watercraft having an inboard engine, includes a standoff box configured to continuously provide power to the drive unit as the drive unit vertically moves from a raised mode to a lowered mode, thereby lowering a thrust point produced by a propeller, all while the watercraft is moving through water and while the propeller is producing thrust. The standoff box can include one or more idler gears that move via a system of brackets relative to an input gear and a transfer gear to maintain rotational engagement between the input gear and the transfer gear, which is joined with the drive unit to rotate the propeller. A related method also is provided.

Abstract: A utility vehicle includes a vehicle interior, a front panel that defines a front side of the vehicle interior and extends in a vertical direction, a floor panel that defines a lower side of the vehicle interior and extends from a lower side of the front panel to a rear side, and is provided with a tunnel portion extending in a front-rear direction on a center side in a vehicle width direction, a propeller shaft that is disposed in the front-rear direction in the tunnel portion and extends to a front side with respect to the front panel, and a cover member that covers space between the propeller shaft and the tunnel portion on a front side of the tunnel portion.

Abstract: An accessory system for a gas turbine engine having a driveshaft with an axis of rotation is provided. The accessory system includes a towershaft coupled to the driveshaft and driven by the driveshaft along a towershaft axis of rotation. The accessory system also includes a shaft including a first shaft bevel gear coupled to a towershaft bevel gear. The shaft is rotatable by the towershaft along a shaft axis of rotation. The shaft axis of rotation is transverse to the towershaft axis of rotation. The accessory system includes a first accessory drive shaft having a first accessory bevel gear driven by the shaft. The accessory system also includes a second accessory drive shaft having a second accessory bevel gear driven by the shaft. A first accessory axis of rotation and a second accessory axis of rotation are substantially transverse to the shaft axis of rotation.

Abstract: A marine propulsion system having a steering axis that allows pivoting of propellers along a first vertical axis directly beneath a gear box located inside the hull of a boat. A lower gear box can be placed within a vented or non-vented tunnel eliminating the need for a rudder and providing directional control of the boat by the orientation of the lower gear box. Surface piercing propellers and/or counter-rotating propellers may be used with the propellers pivoted around the vertical axis of the gear box. The offset steering axis allows pivoting around the first vertical axis wherein a secondary axis is moved with minimal drag providing superior maneuverability at both high and low speeds.

Abstract: A method of controlling a marine propulsion system includes receiving a roll position measurement signal from a roll sensor measuring roll position of a marine vessel and receiving a steering input. The method includes determining based on the roll position measurement signal and the steering input that the roll position of the marine vessel exceeds a port threshold in a port roll direction where no corresponding steering input is present, and determining based on the roll position measurement signal and the steering input that the roll position of the marine vessel exceeds a starboard threshold in a starboard roll direction where no corresponding steering input is present. A steering compensation is then determined based on the roll position measurement signal, and an actuator is controlled to effectuate the steering compensation to reduce a magnitude of the roll position of the marine vessel.

Abstract: A lubrication system in a marine drive has a lubrication circuit that conveys lubrication to componentry of the marine drive and a lubrication service port connected to the lubrication circuit. The lubrication system further includes a pump disposed in the marine drive, wherein the pump pumps lubrication through the lubrication circuit. A hydraulic valve is connected to the lubrication circuit, wherein the hydraulic valve has a normal operating position wherein lubrication in the lubrication circuit is pumped by the pump to the componentry, and has a servicing position wherein lubrication in the lubrication circuit is pumped by the pump to the lubrication service port.

Abstract: A stern drive for a marine vessel comprises a gimbal housing that is configured for connection to the transom of the marine vessel; a gimbal ring that is steerable with respect to the gimbal housing about a vertical steering axis; a drive leg that is trimmable with respect to the gimbal ring about a horizontal trim axis, wherein the drive leg supports a propulsor for propelling the marine vessel; a trim actuator that is configured to trim the drive leg about the trim axis; and a cradle that decouples the drive leg from the transom of the marine vessel and pivots with and supports the drive leg and as the trim actuator trims the drive leg about the trim axis.

Abstract: A stern drive is for a marine vessel. The stern drive comprises a gimbal housing that is configured for connection to the marine vessel, a gimbal ring that is steerable with respect to the gimbal housing about a vertical steering axis, a driveshaft housing that is connected to the gimbal ring, and a trim actuator that is configured to trim the driveshaft housing about a horizontal trim axis. The trim actuator has a first end that is pivotably connected to the gimbal ring at a horizontal first pivot axis and a second end that is pivotably connected to the driveshaft housing at a horizontal second pivot axis. A resilient driveshaft housing vibration isolator is located along the second pivot axis. The resilient vibration isolator isolates vibration forces on the driveshaft housing. A resilient gimbal ring vibration isolator is located along the trim axis. The gimbal ring vibration isolator isolates vibration forces on the gimbal ring.

Abstract: An improved marine drive system for a marine vessel includes a longitudinally extending drive shaft assembly, a hydraulic cylinder and piston assembly pivotally attached between the drive shaft assembly and the vessel. The cylinder has a first fluid filled cylinder chamber that retains a coiled spring that urges a translatable cylinder piston through a second fluid cylinder chamber to extend the piston rod from said hydraulic cylinder lowering the drive shaft assembly. Fluid lines in communication with switch controlled valves allow for selective evacuation of fluid from the first fluid filled chamber to reduce fluid pressure to move the piston in response to fluid pressure in the second cylinder chamber to collapse the spring to retract the rod to raise the drive shaft assembly.

Abstract: A marine propulsion system is for propelling a marine vessel in water. The system comprises an outboard motor that is coupled to a marine vessel, and that comprises an exhaust gas relief outlet that is located above the water when the outboard motor is at idle speed. A conduit conveys exhaust gas from the exhaust gas relief outlet to a discharge outlet located on the marine vessel.

Abstract: Methods and systems are for controlling movement of at least one propulsion unit on a marine vessel. The method comprises plotting a first plurality of points representing a first surface of a first propulsion unit and plotting a second plurality of points representing a second surface. The method further comprises limiting movement of at least the first propulsion unit such that the first surface does not come within a predetermined distance of the second surface during said movement.

Abstract: A propeller drive assembly, for steering and driving a ship (1), comprises a drive motor (2) and a transmission housing (4) secured to a ship hull and a control housing (7) secured to an exterior surface of the hull. The control housing (7) comprises a propeller (8) supported on a driven shaft (6) and the control housing (7) is pivotably coupled, via a steering shaft (10), to the transmission housing (4) for steering the ship (1). A transmission output shaft (5) is connected with the driven shaft (6) and a lubricant circuit of the transmission housing (4) is separate from a lubricant circuit of the control housing (7). At least one sealing element is provided, in a region of a shaft passage of the transmission output shaft (5) and in a region of a shaft passage of the steering shaft (10), for mutually sealing the transmission housing lubricant circuit and the control housing lubricant circuit.

Abstract: A gimbal assembly for a watercraft propeller propulsion system including first and second generally cylindrical gimbal ends each having a pair of diametrically opposing gimbal yokes, and an external gimbal ring pivotally coupled to the opposing gimbal yokes of each of the first and second gimbal ends. The gimbal ring may include a zigzag shaped gimbal ring body with opposing extensions orthogonal to opposing depressions and corresponding pairs of opposing gimbal pin couplings. The opposing gimbal yokes of each gimbal end may include opposing gimbal pin couplings for coupling to the couplings of the gimbal ring. Each gimbal end may be assembled through one face of the gimbal ring and internally coupled to pin couplings of an opposite face of the gimbal ring. The gimbal pins may be clamped with U-bolts. The opposing gimbal yokes may have minimal clearance around a universal joint. A bellows may be mounted externally.

Abstract: The present invention discloses apparatuses, systems, and methods for operating a marine vessel, drilling subsea wells, and producing hydrocarbons therefrom. The marine vessel comprises at least two matching pairs of controlled azimuthing propulsion devices to ice-vane the vessel in the event of a changing ice drift or other conditions and keep station in a body of water containing pack ice. In one embodiment, a matching pair of azimuthing propulsion devices are provided. In one embodiment, the propulsion devices share a single physical axis of rotation and in another each propulsion device has its own physical axis of rotation. In another embodiment, the azimuthing propulsion devices are controlled by an automatic control system with a feedback loop. In yet another embodiment, the vessel is substantially oblong having a centrally mounted turret with mooring lines capable of disconnecting from the vessel.

Abstract: A joint 10 is shown for transmission of torque between an input shaft 12 and an output shaft 14. In the form shown, the joint 10 comprises an outermost helical coil spring 16 and an innermost helical coil spring 18, both of which are connected at their respective opposite ends to the input shaft 12 and to the output shaft 14. The innermost helical spring 18 is arranged to be entirely located within, and co-axially aligned with, the outermost helical spring 16 along the same centerline. The springs 16, 18 are arranged to be counter wound relative to one another to provide delivery of torque in a stabilised manner reflected in a significant reduction in the vibration observed within the joint 10 during use. The joint 10 is also arranged for transmission of thrust (or axial force) between the input shaft 12 and the output shaft 14.

Abstract: A method and a conversion kit are provided for assembling marine propulsion systems such as those comprised of a Mercruiser Alpha One® type sterndrive unit, an OMC Cobra® type inboard engine and a transom assembly, and attaching the propulsion systems to marine vessels. The method and the kit use commercially available parts and minimal special hardware. The technique involves a modified transom assembly comprised of an inner transom plate, a gimbal housing, a gimbal ring equipped with machined custom-made hinge pins, two trim cylinders with corresponding trim pins, and a bell housing with specially designed bellows and adaptor nipple. The invention is also applicable to the assembling of other marine propulsion systems that are comprised of equivalent combinations of similar sterndrive units attached to other similar inboard engines by means of transom assemblies.

Abstract: An adjustable propeller assembly that includes a propeller housing and a drive shaft. A propeller shaft is linked with a propeller. The propeller is linked with a pivotal housing. A coupling member is connected to the drive shaft and propeller shaft. The coupling member pivotally transmits a torque from the drive shaft to the propeller shaft. An actuator is connected to the pivotal housing.

Abstract: A method and a conversion kit are provided for assembling marine propulsion systems such as those comprised of a Mercruiser Alpha-One-type sterndrive unit, an OMC Cobra-type inboard engine and a transom assembly, and attaching the propulsion systems to marine vessels. The method and the kit use commercially available parts and minimal special hardware. The technique involves a modified transom assembly comprised of an inner transom plate, a gimbal housing, a gimbal ring equipped with machined custom-made hinge pins, two trim cylinders with corresponding trim pins, and a bell housing with specially designed bellows and adaptor nipple. The invention is also applicable to the assembling of other marine propulsion systems that are comprised of equivalent combinations of similar sterndrive units attached to other similar inboard engines by means of transom assemblies.

Abstract: A transom shield assembly adapted to be coupled to a transom of an inboard/outboard boat includes a transom shield, and a cover, attachable to the transom shield, for covering a trim pump. The transom shield assembly permits a trim pump to be hydraulically connected to a trim cylinder to form a tilt/trim assembly and, after hydraulically connecting the trim pump to the trim cylinder to form a tilt/trim assembly, permits the tilt/trim assembly to be installed on the inboard/outboard boat without hydraulically disconnecting the trim pump and the trim cylinder.

Abstract: A marine propulsion device is provided with an access opening through a portion of its gimbal housing. At least two support locations, formed integrally with the gimbal housing, provide locations to support a swivel shaft that attaches a gimbal ring to the gimbal housing. A steering lever is attached to the swivel shaft at a location between the points of support. The shaft extends through cylindrical holes in both support portions of the gimbal housing and a nut extends at least partially through one of the cylindrical holes to retain the swivel shaft and steering lever in position. The nut is removable from the shaft by accessing the nut through the opening formed in the support structure of the gimbal housing.

Abstract: An improved amphibious drive system for a watercraft. The amphibious drive system features a paddled drive wheel which is operatively mounted to a drive frame. The drive frame pivots about a horizontal pivot joint. The drive wheel can thereby be raised and lowered with respect to the watercraft. In the elevated position the drive wheel is only partially submerged in the water (such that the drive wheel may operate like a paddlewheel). In the lowered position the drive is submerged more deeply in the water. The amphibious drive system also features a mount plate for attaching the amphibious drive system to the transom of the watercraft. A swing-arm frame links the drive frame to the mount plate. The swing-arm frame pivots in the horizontal direction relative to the watercraft via a vertically-oriented kingpin. This action angularly offsets the thrust from the drive wheel, thereby allowing steering.

Abstract: A marine propulsion system is configured to be preassembled prior to the attachment of a marine engine to the marine vessel. In other words, the marine engine is attached to a transom plate, a gimbal ring, and a bell housing prior to insertion of the engine into the marine vessel. The subassembly is then moved rearwardly to cause the bell housing, gimbal ring, and portion of the transom, bracket to pass through a preformed opening in the transom. Subsequently, a transom ring is attached to the transom bracket to affix the subassembly to the transom. Then a marine drive unit is attached to the bell housing.

Abstract: A hydraulic system for a sterndrive marine propulsion device directs the flow of hydraulic fluid through the body and peripheral components of a gimbal ring in order to reduce the number and length of flexible hydraulic conduits necessary to conduct pressurized hydraulic fluid from a pump to one or more hydraulic cylinders used to control the trim or tilt of a marine drive unit relative to a gimbal housing.

Abstract: An improved marine vessel includes a hull, the hull including a transom and having a predetermined waterline intersecting the hull and the transom. The vessel further includes an upper driveshaft disposed above the waterline, an engine disposed within the hull including an engine drive shaft, and a transmission shaft. The transmission shaft is configured to operatively couple the engine drive shaft to the upper drive shaft. The transmission shaft extends in an inclined orientation relative to a bottom of the hull between the engine drive shaft and the upper drive shaft. The vessel includes a stern drive attached to the transom, wherein the stern drive operatively couples the upper drive shaft to a propeller.

Abstract: A ball and socket joint assembly for a water vehicle outdrive system pivots both the trim-lift and the rudder as well as provides a reverse thrust without the need of a shifting mechanism. The ball and socket joint assembly includes a control mechanism for generating a user input and directing the outdrive system to rotate freely in a select arcuate path so that the water vehicle can be propelled in a corresponding direction, a ball and socket joint section operably connected to the control mechanism for cooperating therewith to selectively position the outdrive system corresponding to the user input, and a support mechanism for assisting to maintain the ball and socket joint section at a substantially stable position during operating conditions. The support mechanism is selectively operable independently of the control mechanism so that a user may pivot the outdrive during non-operating conditions, for maintenance, repairs and the like.

Abstract: The dual propeller surface drive propulsion system for boats is a combined propulsion and steering system for vessels with inboard engines comprising an enclosed thrust bearing assembly mounted to the transom of the vessel, a transom box mounted to the transom of the vessel that encompasses the thrust bearing assembly, an articulated outdrive pivotally connected to the transom box, a gearbox contained within the articulated outdrive, two counter rotating propeller shafts equipped with surface-piercing propellers and a steerable rudder system. Counter-rotating propellers reduce propeller-induced torque. By combining an articulated outdrive with a steerable rudder greater maneuverability of the vessel is achieved.

Abstract: The invention pertains to a theft preventive installation on a boat. Particularly, it is directed to prevent a theft of the drive for the boat at its connection to a housing containing the drive shaft from the motor. It is commonly known that up to six bolts connect the drive to the housing. This particular connection is prone to be broken by unscrewing the bolts whereby the drive can easily be removed from the housing and thereby from the boat. According to the invention, the view of the bolts is obstructed whereby any application of tools to the bolts is prevented. In most installations, there are four bolts placed in a pattern with two bolts each on each side of the upper section of the drive. A plate having inwardly facing flanges thereon is placed under the bolts of each side of the drive. This will securely fasten the plates under the bolts.

Abstract: An improved drive unit for propelling a watercraft through shallow water comprising a steering box pivotally attached to the watercraft transom; a first drive shaft extending through the transom to the steering box; a second drive connected to said first drive shaft by means of a double universal joint; and a drive shaft housing for the second drive shaft, the housing being pivotally connected to the steering box to allow the drive shaft housing to pivot vertically on the steering box. A propeller is mounted to the second propeller shaft for propelling the watercraft. A single action spring-return hydraulic ram, said ram having a housing, a piston and a piston rod, is attached to absorb movement of the shaft housing in the event that an obstacle is encountered. The hydraulic ram is provided with means for moving the ram piston and thereby the piston rod to raise and lower said drive shaft housing and propeller.

Abstract: A fluid cylinder such as a hydraulic cylinder used on marine engines to control the steering direction and/or trim position of a propeller shaft comprises internally ported fluid lines located in line with the longitudinal axis of the cylinder and may be either ported in the base of such a cylinder or, alternatively, in the head.

Abstract: A stern drive system having an outdrive rotatable about a generally horizontal axis to impart a desired trim or tilt to the drive system is provided. The system includes a gimbal ring that defines an inner region. The gimbal ring is configured to pivotally receive a first anchor pin. A tilt-trim assembly is affixed to the outdrive, and the tilt-trim assembly has one respective end thereof configured to pivotally receive a second anchor pin supported by the outdrive. The assembly includes a single cylinder through the inner region of the gimbal ring and has one end thereof connected to the first anchor pin so that when the cylinder is actuated the outdrive is rotated about the generally horizontal axis.

Abstract: A stern drive system having an outdrive generally disposed downstream relative to water flow aft a transom of the boat is configured to be rotated about a generally horizontal axis to impart a desired trim or tilt to the drive system. A tilt-trim subsystem assembly is affixed to the outdrive and has one respective end thereof configured to pivotally receive an anchor pin supported by the outdrive. The assembly includes at least one cylinder having one end thereof connected to another anchor pin so that when the cylinder is actuated by a circuit therein the outdrive and the tilt subsystem assembly are rotated about the generally horizontal axis during tilt maneuvers. A housing is provided to shield the tilt assembly and configured within the footprint of the outdrive to avoid resistance to water flow. Additionally, the housing may be configured to visually shield the tilt assembly from observers.

Abstract: A drive apparatus (12) for a boat having a planing hull (14) including a notch (24). An engine (30) and a transmission (32) are mounted within the hull. A propeller shaft (38) is connected to the transmission with a universal joint (34) and extends rearwardly therefrom into the notch. The propeller shaft passes through a shaft support (56), and a propeller (46) is affixed to the propeller shaft behind the shaft support. The shaft support depends from a strut (58), which is mounted on the underside of a pivot arm (50). A trim drive (62) is mounted within the hull and above the notch and the pivot arm. A linearly extendable trim drive shaft (64) extends between the trim drive and the pivot arm and, when the trim drive is actuated, pivots the pivot arm, and thus the propeller, selectively upwardly and downwardly to adjust trim for maximum drive efficiency under various boat load distribution, water surface and wind conditions.

Abstract: Stern drive assembly configured for utilization in an inboard/outboard power plant for a boat. The stern drive assembly includes a central rigid core that is configured at an upper portion to be coupled to the stern of a carrying boat. A lower portion of the core is designed to accept a boat-moving force generated by a water propulsion unit that is coupled thereto. A thin-walled housing is configured to be secured about a predominance of the centrally located rigid core. The housing has an outer surface that establishes an exterior of the stern drive assembly and an inner surface directed generally toward the central rigid core. A portion of an exterior surface of the central rigid core is configured to cooperate with a corresponding portion of the inner surface of the thin-walled housing. These two portions, when in cooperative orientation one with the other, form a functional feature for the stern drive assembly.

Abstract: A marine propulsion system is provided with a drive unit that is attachable to a transom of a marine vessel and provided with steering cylinder assemblies and trimming cylinder assemblies which are connected to a common location on a structural member, such as a gimbal ring. This arrangement improves the geometric relationship between the steering and trimming functions. In addition, the hydraulic steering system is provided with pressure relief valves that are located at the transom of the marine vessel in order to shorten the distance of the hydraulic conduits extending between the pressure relief valves and the steering cylinders.

Abstract: A tilt-trim subsystem assembly affixed to an outdrive of a stern drive that may be supported by a gimbal unit and may be configured to rotate about a predetermined axis to impart a desired trim or tilt to the drive system is provided. The tilt-trim assembly has one respective end thereof configured to pivotally receive one anchor pin supported by the outdrive. The assembly includes one or more cylinders having one end thereof pivotally connected to another anchor pin so that when the cylinder is actuated the outdrive and the tilt-trim subsystem assembly are jointly rotated about the predetermined axis.

Abstract: A double-acting hydraulic cylinder and piston rod unit having fluid hoses for conducting fluid thereto. A generally flat outer end is provided on the piston or cylinder. A bracket has a spherical socket and either the piston rod end or cylinder has a spherical ball portion swively mounted in the socket. A yoke has a slot in which the generally flat end is slidably mounted for sliding in opposite directions. The flat end prevents relative rotation between the rod and cylinder about a longitudinal axis. Guide slots are provided and arranged at right angles to the yoke slot, the yoke being slidable in the guide slots whereby the unit can swivel about the socket and can slide in the opposite directions in the yoke and the unit can also move at right angles thereto by sliding with the yoke in the guide slots. The piston rod and cylinder are prevented from rotating relative to one another about their longitudinal axis and thereby prevent twisting of the hoses.

Abstract: A vertical trim system for a marine inboard-outboard outdrive includes a transom plate (12) and arms (18, 20) having first ends attached to the transom plate and second ends attached to a gibal ring (76) of the outdrive.

Abstract: A marine propulsion system having an integral-piece gimbal ring and steering means is provided. The system is made up of a gimbal housing affixed through the rear of a boat transom and a gimbal ring pivotally connected to the gimbal housing. The system is further made up of a steering assembly configured to provide pivotal movement of the gimbal ring relative to the gimbal housing about a steering axis. The gimbal ring and the steering assembly comprise an integral-piece assembly.

Abstract: An assembly and techniques for facilitating assemblage of a drive unit to a gimbal housing in a boat are provided. The assembly uses a universal joint (U-joint) in the gimbal housing for pivotally engaging the drive unit to the gimbal housing. The U-joint includes an input shaft that receives driving power and an output shaft connectable to the drive unit. The assembly further uses an alignment subassembly configured to support the U-joint in an alignment position while its output shaft is being connected to the drive unit.

Abstract: An inboard/outboard boat drive having a housing with first and second ends and a cavity passing between the housing first and second ends. The first end of housing is pivotally mounted on the boat stern. The drive includes an input drive shaft for coupling to an engine mounted within the boat, an intermediate drive shaft disposed within the housing cavity, a first universal joint coupling the input device shaft and the intermediate drive shaft, together with an output drive shaft coupled to a propulsion element and a second universal joint coupling the intermediate drive shaft and the output drive shaft.

Abstract: A boat drive mechanism is constructed of an engine mounted in the boat; a propeller; a drive shaft having a front end connected to the engine and a rear end extending through the exterior of the transom; a propeller shaft having a rear end connected to the propeller and a front end, with the propeller shaft being moveable between a lowered position and a raised position; and a universal joint connecting the drive shaft rear end to the propeller shaft front end and spaced from the rear of the transom, the universal joint being the sole thrust connection between the drive shaft and the propeller shaft. A propeller tube surrounds at least a part of the propeller shaft. The propeller tube and shaft are raised and lowered by a first hydraulic cylinder pivotally connected to the propeller tube and the transom above the drive shaft.

Abstract: A mount for an outboard motor is disclosed in which the cylinder block of the motor is within the hull and the gear box and propeller are outside the hull. The drive shaft passes through the mount from the block to the gear box. The mount permits the motor to be swung about a horizontal axis to raise and lower the propeller. It also permits the motor to perform rotary steering oscillations about an inclined axis which passes through the propeller, or close to the propeller. Because the propeller is oscillated about an axis which passes through or close to it, it remains on the boat center line when the motor is turned for steering purposes and moves to a position in which the line of thrust is downwards.

Abstract: An adjustable propeller system includes an outboard drive portion having a propeller. At least one linearly extendable and retractable trim arm is mounted between an outboard plate and the propeller to adjust the trim angle between the outboard plate and the propeller. An upper arm and a lower arm are each pivotally mounted to a transom mounting plate and pivotally mounted to the outboard mounting plate. The upper and lower arm are linearly extendable and retractable to adjust the depth of the outboard drive portion.

Abstract: A vertical trim system for a marine inboard-outboard outdrive includes a transom plate defining an opening therethrough and having first and second sides, the first side adapted to be mounted to a boat transom. At least one arm includes first and second ends, the first end being pivotally coupled to the second side of the transom plate, such that the arm pivots about a horizontal axis. The second end of the arm is adapted to be pivotally coupled to a gimbal ring of an outdrive.

Abstract: A marine outdrive attachable to the transom of a small fishing boat having an inboard engine. The marine outdrive includes a kit having through transom mounting plate, a fabricated propeller shaft housing pivotally attached to a pivot member which is pivotally attached to said transom plate thereby providing freedom of movement in two planes. The outdrive is supported and maintained under tension in the horizontal plane by a flexible member and a shock absorber thus maintaining automatically contact with any surface in contact with the boat's keel. A kit is provided containing all essential components and instructions for installation of the outdrive on a small fishing craft. All working components are off the shelf stock items or fabricated for easy field repair.

Abstract: Boat propeller drive unit, comprising a frame-like carrier (1) intended to be fixedly joined to a boat transom, and a propeller rig (4) which is suspended in a fork (13) for trim and tilting movement relative to the fork about a horizontal axis (a). The fork in turn is mounted in the carrier for pivoting about a vertical steering axis (b). A pair of hydraulically operated piston cylinder devices (18,20) are pivotally joined at opposite ends to the rig (4) and to the legs (12) of the fork.

Abstract: A number of embodiments of outboard drive systems that include a combined vertically extending drive shaft driven by the propulsion unit and which drives a generally horizontally extending propeller shaft that drives a propeller positioned substantially rearwardly of the transom. The propulsion system is supported for steering and trim movement about respective spaced apart axes and these axes are both disposed substantially below the transom of the associated watercraft. The propeller driven by the propeller shaft is disposed further from the trim axis than the forward end of a tiller that is affixed to the outboard drive for affecting the steering and trim movement.

Abstract: A number of embodiments of outboard drive systems that include a combined vertically extending drive shaft driven by the propulsion unit and which drives a generally horizontally extending drive shaft that drives a propulsion device positioned substantially rearwardly of the transom. The propulsion system is supported for steering and trim movement about respective spaced apart axes and these axes are both disposed substantially below the transom of the associated watercraft.

Abstract: An improved fin structure for attachment to the propeller shaft mount of a surface piercing marine outdrive apparatus. The fin structure has one fin member at one side of the mount for the propeller drive shaft of the marine outdrive. The fin member is so situated that it is in a position to destroy any side thrust exerted by the propeller on the water so as to avoid "walking" of the mount on the water and the propeller laterally.