Abstract: Methods and systems are provided for controlling a propulsion system of a vessel including an engine and a propeller. In one embodiment, the method comprises independently adjusting each of an engine setting and a propeller setting responsive to real-time vessel operating data.

Abstract: An outboard motor includes a variable speed mechanism portion arranged to transmit a driving force to propellers such that the driving force is changed in its speed by a low reduction ratio and a high reduction ratio, an upper housing that houses the variable speed mechanism portion, oil tanks provided on the outside of the upper housing and arranged to retain oil to be supplied to the upper housing, and an oil lubrication route arranged to supply oil in the oil tanks to the upper housing and to collect the oil supplied in the upper housing in the oil tanks. The above arrangement provides a boat propulsion unit capable of allowing both a performance of acceleration and a maximum speed to approach a level desired by a user and to prevent the occurrence of a loss of the driving energy of an engine.

Abstract: A power transmission system for a marine propulsion unit includes a case arranged to be supported on a hull; a propeller supported at the lower end portion of the case for rotation about an axis extending in a fore-and-aft direction; a transmission housed in the case and having an axis with planetary gear trains extending vertically to receive an output from an engine, and change the speed of the output prior to transmission thereof; and an interlocking device arranged to receive the output from the transmission and transmit the output to the propeller. A speed reduction device is arranged such that it is interposed between the transmission and the interlocking device, receives the output from the transmission, and decelerates the output to transmit it to the interlocking device. This arrangement reduces the weight of a transmission unit in a power transmission system of a marine propulsion unit and decreases an external size of the transmission unit.

Abstract: A power transmission system of a marine propulsion system includes a transmission arranged to change the speed of an output from an engine and then to transmit the output to a propeller shaft. Wet-type multi-plate clutches provided in the transmission include a plurality of clutch plates fitted to a clutch rotating body for axial movement with the clutch rotating body. The clutch rotating body includes an oil reservoir in its inner bottom portion and arranged to hold lubricating oil and a peripheral wall arranged to cover the oil reservoir from the radial outside and fit to each of the clutch plates to permit axial movement of the clutch plates. Communicating holes are arranged on the peripheral wall such that they communicate the oil reservoir side to the outside of the clutch rotating body in the radial direction.

Abstract: An outboard motor includes a lower casing provided below an upper casing, amounting plate provided above the upper casing, and an engine with a vertically-arranged crankshaft mounted on the mounting plate. The rotation of the crankshaft is transmitted to a drive shaft that is pivotally supported in the upper casing, changed in speed by a transmission mounted on the drive shaft, and transmitted to a propeller shaft that is pivotally supported in the lower casing. The outboard motor has upper mounts and lower mounts arranged to mount the outboard motor on a hull. The upper mounts are disposed on upper lateral surfaces of the upper casing, and the lower mounts are disposed on lower lateral surfaces of the upper casing. The outboard motor simplifies the upper casing for disposing a transmission therein and assembly and maintenance thereof.

Abstract: A method to assemble a marine drive system wherein an acceptable-unacceptable criterion on the torsional vibration of a shaft of the marine drive system is established based on the correlation between the torsional stiffness of a propeller shaft and the moment of inertia of a propeller. A desirable elastic coupling for the marine drive shaft is selected based on the criterion. The marine drive system is assembled by using a flywheel, a marine reverse and reduction gear, and an elastic coupling, whose property is changeable, lying between an input shaft of the marine reverse and reduction gear and the flywheel.

Abstract: The present invention relates to an outboard drive device (10) comprising an outboard motor (11) having a crankshaft (16), wherein said outboard drive device (10) further comprises a propeller which propeller is below the hull (13) of a boat when said outboard drive device (10) is operated, and a power coupling system for transferring power from the motor (11) to the propeller. The power coupling system comprises a power transfer device (17) for transferring output power from the crankshaft (16) to a transmission drive shaft (19) of a transmission (18), and a power transfer means (20) for transferring output power from the transmission (18) to a drive shaft (21) of an endless loop flexible drive coupling (22) operatively connecting said transmission (18) to a propeller shaft (12) for driving said propeller, wherein the crankshaft (16) is substantially horizontal and substantially parallel to the propeller shaft (12) when said outboard drive device (10) is operated.

Abstract: A hybrid marine power train system is provided that facilitates selective use of one of multiple prime movers for powering and driving a boat. The multiple prime movers can include an internal combustion engine and an electric motor which can itself be part of a motor/generator assembly. The system further includes a power-take-in assembly that can have either an active or passive clutching device for selectively importing power from the prime movers into the transmission. The system is configured so that the second prime mover occupies relatively little space within an engine compartment of the boat, for example when compared to an amount of space occupied by the first prime mover and transmission. Since the second prime mover occupies relatively little space within the engine compartment, the system can be readily retrofitted to existing marine power train systems.

Abstract: A marine vessel propulsion unit includes an engine, a drive shaft, a single propeller shaft, a single propeller, and a planetary gear mechanism. The drive shaft is arranged to extend vertically. The propeller shaft is arranged to extend in a direction intersecting the drive shaft. The rotation of the engine is transmitted to the propeller shaft via the drive shaft. The propeller is arranged to rotate together with the propeller shaft. The planetary gear mechanism is arranged at the front relative to the drive shaft and coaxial to a central rotation axis of the propeller shaft. The planetary gear mechanism is arranged to decelerate the rotation from the drive shaft and transmit the decelerated rotation toward the propeller shaft.

Abstract: An outboard engine system includes: a casing coupled to a swivel case via a swivel shaft; an engine mounted in an upper part of the casing such that a crankshaft of the engine is vertically arranged and a cylinder block of the engine faces in a direction opposite to the swivel shaft; a torque converter; a vertically arranged output shaft connected to the crankshaft through the torque converter; a horizontally arranged propeller shaft provided below the output shaft; and a forward-reverse shifting gear mechanism for providing a connection between the output shaft and the propeller shaft; the torque converter, the output shaft, the propeller shaft and the forward-reverse shifting gear mechanism being disposed in the casing. The crankshaft and the torque converter which is coaxially connected to a lower end of the crankshaft are disposed above the swivel shaft; and the torque converter and the output shaft which is disposed behind the swivel shaft are connected to each other via a transmission device.

Abstract: A marine vessel propulsion unit includes an engine, a drive shaft, a propeller shaft, a propeller, an intermediate shaft, a forward-reverse switching mechanism, and a shock reduction mechanism. The intermediate shaft is arranged on a central rotation axis of the propeller shaft. The intermediate shaft is arranged to transmit rotation between the drive shaft and the propeller shaft. The forward-reverse switching mechanism is arranged to switch a rotational direction of the propeller shaft to a forward drive direction or a reverse drive direction. The shock reduction mechanism includes a plurality of spring members and a pair of stopper portions. The shock reduction mechanism is arranged on the central rotation axis of the propeller shaft. The plurality of spring members are arranged to absorb a force in the rotational direction by elastically deforming in the rotational direction when the force in the rotational direction is applied to the intermediate shaft.

Abstract: A marine vessel propulsion unit includes an engine, a drive shaft, a propeller shaft, a propeller, an intermediate shaft, and a first reduction gear mechanism. The drive shaft is arranged to be rotated by the engine. The rotation of the drive shaft is transmitted to the propeller shaft. The propeller is arranged to be rotated together with the propeller shaft. The intermediate shaft is arranged on a central rotation axis of the propeller shaft or an extension of the central rotation axis. The intermediate shaft is arranged to transmit rotation between the drive shaft and the propeller shaft. The first reduction gear mechanism is arranged on a central rotation axis of the propeller shaft or the extension of the central rotation axis. The first reduction gear mechanism is arranged to decelerate the rotation of the intermediate shaft so as to transmit the decelerated rotation to the propeller shaft during both forward propulsion and backward propulsion.

Abstract: An outboard motor is provided that can include an exhaust guide, a shift shaft, a shift shaft rotating mechanism, and a shifting mechanism. The exhaust guide, on which an engine can be mounted, can be utilized to fix the relative positions of an axis of the shift shaft and a body of the shift shaft rotating mechanism for facilitating highly accurate and well-executed shifting of a propeller to or from one of forward and reverse rotating directions. The shift shaft can be rotatably supported by the exhaust guide, and the shift shaft rotating mechanism can be fixed to the exhaust guide. Further, the shift shaft rotating mechanism can be configured to selectively rotate the shift shaft.

Abstract: The present invention provides a marine reversing gear assembly, wherein a manual directional control valve 7a and an electromagnetic directional control valve 7b for a forward/reverse directional control valve 7 for hydraulic oil supply circuit 10 have a common structure of an oil line joint surface for the hydraulic oil supply circuit 10 for friction discs of a forward clutch 2f and a reverse clutch 2a, and the forward/reverse directional control valve 7 for the hydraulic oil supply circuit 10 can be changed to either the manual directional control valve 7a or the electromagnetic directional control valve 7b by exchanging spools 7c or 7e of the manual directional control valve 7a or the electromagnetic directional control valve 7b. Therefore, the operational manner of the forward/reverse directional control valve for the hydraulic oil supply line of a marine reversing gear assembly can be changed quite easily between the manual directional control valve and the electromagnetic directional control valve.

Abstract: A two speed transmission including an input shaft; a lay shaft spaced from the input shaft; a first gear train connecting the input shaft to the lay shaft; a second gear train connecting the lay shaft to an output shaft, the gear train including a one way clutch or similar; and a clutch for engaging the input shaft with the output shaft. When the clutch is disengaged, power is transmitted from the input shaft via the gear trains and the lay shaft via the one way clutch to the output shaft which typically provides first or low gear for use in low speed maneuvering or where greater torque is required. With the clutch engaged, power may be transmitted from the input shaft directly to the output shaft to provide a second gear for when the watercraft is cruising.

Abstract: A marine drive system mounted in the hull of a marine craft, the marine drive system comprising an engine connected to a gearbox by means of a drive shaft (532), a propeller (1) connected to the gearbox by means of a propeller shaft (501), wherein the gearbox and the propeller are formed as a single rigid body for flexibly mounting in the hull of the marine craft as a single unit, and wherein the engine, gearbox and propeller are positioned such that they are always generally aligned with the longitudinal axis of the craft.

Abstract: A shock absorber for a marine propulsion device is configured to provide an adapter, coupler and resilient device which can be assembled into a unit, or module, that can be inserted into a propeller. The resilient device includes two helical springs that urge the coupler into a central position with respect to the adapter and resist relative axial motion between the adapter and coupler. The shock absorber is intended to absorb the forces which occur during a shift from neutral to forward gear of the marine propulsion device.

Abstract: A hydraulic valve, such as a rotary valve, is connected in fluid communication with a hydraulic actuator that, in turn, causes a clutch to move between forward, neutral, and reverse gear positions. A marine transmission is caused to shift between these gear positions in response to movement of a spool of the hydraulic valve, which can be a rotary valve. Movement of the valve causes an actuator to move to the selected gear position and maintain that gear position until a subsequent movement of the hydraulic valve.

Abstract: A boat propulsion unit has a construction that prevents a structure near a drive shaft from becoming complicated and increased in size. The boat propulsion unit preferably in the form of an outboard motor includes a front propeller that is rotated together with a front propeller drive shaft during both forward travel and reverse travel of the boat, a rear propeller that is rotated together with a rear propeller drive shaft in an opposite direction of the front propeller during both of the forward travel and the reverse travel of the boat, and a forward-reverse drive that is arranged on an axis of the front propeller drive shaft and the rear propeller drive shaft, and that can be switched between a direction in which the front propeller drive shaft and the rear propeller drive shaft are rotated during the forward travel of the boat and a direction in which the front propeller drive shaft and the rear propeller drive shaft are rotated during the reverse travel of the boat.

Abstract: An outboard motor S has a first drive shaft 31 directly interlocked with an engine E, a second drive shaft 32, an intermediate gear mechanism 33 interlocking the first drive shaft 31 and the second drive shaft 32, an output gear mechanism 50 driven by power transmitted thereto through the second drive shaft 32, a propeller shaft 17 driven for rotation by power transmitted thereto through the output gear mechanism 50, and a gear case 13 holding the output gear mechanism 50. The second drive shaft 32 extends downward beyond a vertical position corresponding to the lower end of the first drive shaft 31. The gear case 13 is provided with water intakes 98 through which a water pump 90 sucks water in a space between the first drive shaft 31 and the output gear mechanism 50 with respect to a vertical direction on the front side of the second drive shaft 32. The space for the water intakes 98 can be easily secured because the second drive shaft 32 is disposed on the rear side of the first drive shaft 31.

Abstract: The invention relates to a marine-vessel transmission having an input-drive shaft (10), which extends along an input-drive shaft axis (A) and on which an input-drive shaft gearwheel (12) is arranged, a first pinion shaft (14), which extends coaxially with respect to the input-drive shaft (10) and on which a first pinion (16) is arranged, a second pinion shaft (24), which extends parallel to the input-drive shaft (10) and on which a pinion shaft gearwheel (28), which engages with the input-drive shaft gearwheel (12), and a second pinion (26) are arranged, an intermediate shaft (18), on which a spur gear (20), which engages with the first pinion (16) and the second pinion (26), and a bevel pinion (22) are arranged, and an output-drive shaft (30), which extends along an output-drive shaft axis (P) which runs at an angle (?) of more than 75° with respect to the input-drive shaft axis (A), and on which a spur bevel gear (31) is arranged, which forms a bevel drive with the bevel pinion (22).

Abstract: A boat has a hull, a deck having a deck floor, and an engine disposed in the hull. A top of the engine is disposed vertically below the deck floor. The engine includes a crankcase, a crankshaft, a pair of cylinder banks connected to the crankcase at an angle relative to each other. A transom extends generally vertically upwardly from a rear portion of the hull. A stern drive unit is connected to the transom and is operatively connected to the engine through the transom. In another aspect, a marine engine has a crankcase, a cylinder block, and a crankshaft. An output shaft is disposed vertically above the crankshaft. The output shaft is disposed at least partially internal to the engine. A drive, internal to the engine, is operatively connected to the crankshaft and the output shaft. A driveshaft coupling is disposed on the output shaft.

Abstract: A boat propulsion unit includes a power source, a propeller, a shift position changing mechanism, a control device, and a speed reducing switch. The shift position changing mechanism has an input shaft, an output shaft, and first and second clutches. The first and second clutches change the connection state between the input shaft and the output shaft. In the shift position changing mechanism, the first and second clutches are engaged or disengaged, thereby changing the shift position among forward, neutral, and reverse. The control device controls connecting forces of the first and second clutches so that the propeller generates propulsive forces in the direction opposite to the present propulsive direction of a hull when the speed reducing switch is turned on by the operator of the boat. The boat propulsion unit easily retains the propulsive speed of a hull substantially at zero.

Abstract: A watercraft suitable for operation in rough water conditions is disclosed. The watercraft comprises a central platform (13) and two pairs of hull units (60), a forward pair and an aft pair. The hull units are located on opposite sides of tie platform and extend below the platform, with each hull unit comprising a mount (54) attached to the platform and a trailing hull connected to the mount via a movable hull support. The components of the hull units are connected by joints (58,62) arranged to constrain lateral and axial movement of: the hull relative to the platform (12) but to permit pivoting thereof about the mount (54). Each hull unit has a suspension assembly arranged to support the respective hull units, and comprises a suspension member (66) extending from the platform (12) to a mounting point (20) on the hull aft of the respective mount, and being arranged to accommodate movement of the hull relative t) the platform and to apply damping to movement of the hull.

Abstract: An outboard engine system includes a casing and an engine mounted in an upper part of the casing. The casing also contains a torque converter, and a vertically arranged output shaft connected to a crankshaft through the torque converter. In the torque converter, a turbine runner is arranged above a pump impeller and connected to the output shaft, and a transmission cover is connected to an outer periphery of the pump impeller so as to cover an upper surface of the turbine runner. A drive plate is secured at its central portion to a lower end of the crankshaft by a first bolt, and an outer peripheral portion of the drive plate is secured to the transmission cover by a second bolt. The torque converter is suspended from the crankshaft via the drive plate. Thus, it is possible to provide an outboard engine system which enables support of a torque converter without using any bearing exclusively for supporting the overall weight of the torque converter, thereby reducing the cost.

Abstract: A marine propulsion system includes an engine, propellers rotated by the engine, a transmission mechanism arranged to transmit a driving force of the engine to the propellers with a speed thereof shifted to at least a low speed reduction ratio or a high speed reduction ratio in forward travel and reverse travel, and a gear shift switch operable by a user to shift speed reduction ratios of the transmission mechanism to the low speed reduction ratio in at least the reverse travel. This arrangement provides a marine propulsion system in which both of acceleration performance and a maximum speed can approach levels that a user desires.

Abstract: A propulsion system is provided for an underwater vehicle such as a Remote Operated Vehicle (ROV). Two propellers are independently driven by motors, while the orientation of the propellers is simultaneously controlled by a third motor. A means is provided for reprogramming the control electronics that can be disabled when the vehicle is underwater. The control electronics also provides that all signals including video are transmitted to a base station without requiring coaxial cable.

Abstract: A boat propulsion system includes a drive bevel gear fixed on a lower end of a drive shaft, a forwarding bevel gear and a reversing bevel gear rotatably fitted on a propeller shaft and meshing together with the drive bevel gear, and a dog clutch mounted on the propeller shaft and rotatable with the propeller shaft, moves in an axial direction of the propeller shaft, and meshes together with the forwarding bevel gear or the reversing bevel gear to rotate the propeller shaft, in which the propeller shaft comes in contact with the forwarding bevel gear via a forwarding side buffer member having a disc spring as a component member. The boat propulsion system prevents and minimizes sound and impact even when variations in thrust force occur.

Abstract: A modified marine vessel system including a marine vessel configured to carry and transport marine freight in an ocean environment, and at least one engine module carried on the marine vessel. The engine module includes an engine housed inside a marine freight container. The system further includes a propeller and a power coupling operably connecting the engine and the propeller such that the propeller is rotatably drivable by the engine, wherein the power coupling does not extend through a hull of the marine vessel.

Abstract: An outboard motor includes a variable speed mechanism portion arranged to transmit a driving force to propellers such that the driving force is changed in its speed by a low reduction ratio and a high reduction ratio, an upper housing that houses the variable speed mechanism portion, oil tanks provided on the outside of the upper housing and arranged to retain oil to be supplied to the upper housing, and an oil lubrication route arranged to supply oil in the oil tanks to the upper housing and to collect the oil supplied in the upper housing in the oil tanks. The above arrangement provides a boat propulsion unit capable of allowing both a performance of acceleration and a maximum speed to approach a level desired by a user and to prevent the occurrence of a loss of the driving energy of an engine.

Abstract: A transmission device includes hydraulic type transmission mechanisms arranged to change the speed or the direction of rotation of an engine, and hydraulic pressure control valves arranged to control hydraulic pressure supplied to the hydraulic type transmission mechanisms. The hydraulic pressure control valves are disposed on one side or the other side in the watercraft width direction. The transmission device provides an outboard motor capable of securing cooling characteristics of a hydraulic pressure control valve without incurring complexity in structure and increase in cost.

Abstract: A power transmitting portion of an outboard motor has a power transmitting shaft connected to an output shaft of an engine to rotate together therewith, an oil pump disposed on the power transmitting shaft, and a driving force acquisition mechanism arranged to acquire driving force from the power transmitting shaft. The power transmitting portion is able to provide an outboard motor capable of ensuring a pump discharge amount without incurring an increase in the pump size and the oil amount.

Abstract: The invention is directed to a torque transmission device for a ship for optionally transmitting a drive torque from a main drive or from an auxiliary drive to a propeller shaft (1, 2, 3) of the ship, with a gear unit (10, 11) which can be driven by the main drive and which can be connected to the propeller shaft by a first clutch (14), and with a second clutch (15) by which the auxiliary drive can be connected to the propeller shaft. The gear unit is received in a gear unit housing (6), the first clutch and/or second clutch are/is received in a clutch housing (7) that is separate from the gear unit housing, and the first clutch, the second clutch and/or the auxiliary drive are arranged on the side of the gear unit remote of a propeller.

Abstract: An outboard motor includes a lower casing provided below an upper casing, amounting plate provided above the upper casing, and an engine with a vertically-arranged crankshaft mounted on the mounting plate. The rotation of the crankshaft is transmitted to a drive shaft that is pivotally supported in the upper casing, changed in speed by a transmission mounted on the drive shaft, and transmitted to a propeller shaft that is pivotally supported in the lower casing. The outboard motor has upper mounts and lower mounts arranged to mount the outboard motor on a hull. The upper mounts are disposed on upper lateral surfaces of the upper casing, and the lower mounts are disposed on lower lateral surfaces of the upper casing. The outboard motor simplifies the upper casing for disposing a transmission therein and assembly and maintenance thereof.

Abstract: An actuator for a marine transmission uses four cavities of preselected size in order to provide four potential forces resulting from pressurized hydraulic fluid within those cavities. The effective areas of surfaces acted upon by the hydraulic pressure are selected in order to provide increased force to move the actuator toward a neutral position from either a forward or reverse gear position. Also, the relative magnitudes of these effective areas are also selected to provide a quicker movement into gear than out of gear, given a similar differential magnitude of pressures within the cavities.

Abstract: The invention relates to a ship propulsion unit with drive devices in the hull and all underwater pod, which is located outside of the hull and which has a front propeller and a rear propeller as well as torque transmitting devices between the drive devices and the propellers. The torque transmitting devices contain: a torque transmitting shalt that is shared by both propellers and serves to transmit torque from the drive devices into the underwater pod; front transmission devices, which are placed in the underwater pod and which are located between the shared torque transmitting shaft or both propellers and the front propeller, and; rear transmission devices that are located between the shared torque transmitting shaft of both propellers and the rear propeller. The invention also relates to a ship propulsion method during which a front propeller and a rear propeller, which are assigned to an underwater pod located outside of the hull, are driven by drive devices in the hull via torque transmitting devices.

Abstract: In an outboard motor S, a first drive shaft 31 and a second drive shaft 32 are interlocked by an intermediate gear mechanism 33 including a drive gear 34 mounted on the first drive shaft 31 and a driven gear 35 mounted on the second drive shaft 32. The second drive shaft 32 is supported in an upper bearing 38 and a lower bearing 39 disposed on the upper and the lower side of the driven gear 35. The upper bearing 38 supports an upper end part 32a of the second drive shaft 32 extending upward from the driven gear 35 and the upper bearing 38 is at a vertical position coinciding with that of the drive gear 34. The lower bearing 39 is placed at a position on a lower end part 32b of the second drive shaft 32. The lower end part 32b extends between the driven gear 35 and an input gear 51 included in the output gear mechanism 50.

Abstract: A vertical power unit includes an input shaft and an output shaft which have axes in the vertical direction and are vertically arranged to each other; and a torque converter between the input shaft and the output shaft. The output shaft includes an upper output shaft connected to a turbine runner and a lower output shaft connected to the upper output shaft. An oil tank and an oil pump are provided outside the torque converter. The upper output shaft is provided with a vertical hole which communicates at an upper end with a circulation circuit of the torque converter so as to introduce the oil discharged by the oil pump into the circulation circuit, and a bottom wall which closes a lower end of the vertical hole. Thus, an working oil is constantly supplied to the circulation circuit of the torque converter through the interior of the output shaft, thereby cooling the working oil in the circulation circuit, and improves maintainability of loading devices driven by the output shaft.

Abstract: An outboard motor includes an engine vertically supporting a crankshaft above an engine holder and a shift mechanism switching a rotational direction of a propeller shaft by actuating a shift apparatus through a remote control from a shift lever. The shift mechanism includes a first link mechanism connecting a shift cable extending from the shift lever and a clutch rod extending toward a shift rod, the first link mechanism being disposed in a space formed between a lower surface of the engine and an upper surface of the engine holder and also includes a second link mechanism connecting the clutch rod and the shift rod and disposed in a space between a drive shaft housing and a gear case of the outboard motor.

Abstract: A boat drive system is provided for a power boat which includes an engine having a drive shaft, connected to a pair of propeller shafts. The drive system includes a primary gearbox and opposed outboard gearboxes. The primary gearbox includes a housing and a gear arrangement connected to the engine shaft and the outboard gearboxes, which are connected to the primary gearbox by a transverse shaft, include a housing and a gear arrangement connected to associated propeller shafts. A cooling system is provided including a cooling pad for each gearbox. A support system is provided for each outboard gearbox including a cradle connected to the bearing points on the hull. The engine includes an adapter plate attached to the primary gearbox for movement of the primary gearbox with the engine. In a modified drive system only one outboard gearbox is used in conjunction with a single engine. In another modified drive system a single engine and propeller are used in conjunction with a gearbox having a take-off shaft.

Abstract: A marine drive is engaged with and is driven by a vessel's engine drive shaft. The drive includes: a universal joint secured to the vessel's hull; a first screw shaft supporting a first screw; a first gear set driven by the first screw shaft; a second screw shaft driven by the first gear set; a second gear set driven by the second screw shaft; a third screw shaft driven by the second gear set and supporting a second screw; and a third screw supported by the second screw shaft at its terminal end. The first and second gear sets are enclosed within a water-tight enclosure enabling rotational speed differentiation between the first and second screw shafts and enabling rotational sense reversal between the second and third screw shafts. An actuator provides changes in angle of attack of the second and third screws.

Abstract: A drop in-module consisting of a mass produced engine coupled to a drive system by use of a common mid-section mounting platform. The module provides a single assembly that can be easily installed and removed from a vessel. The drive system is based on motors using a vertical crankshaft orientation joined to a 90 degree gearbox with a forward-neutral-reverse transmission. A speed sensitive clutch arrangement separates the engine from the gearbox. The heat created by the air cooled versions of these engines can be vented into the propeller wash through a passage formed in the mounting plate.

Abstract: An outboard motor includes a case extending generally vertically and supported on a hull. An engine is supported at an upper end of the case. A propeller is supported by a lower end of the case. A drive shaft is supported within the case for rotation about a generally vertical axis. The driveshaft has an upper end operatively connected to the engine and a lower end operatively connected to the propeller. An upper portion of the case includes an elongate extruded portion having substantially the same cross-sectional shape along its length.

Abstract: A propeller power transmission device according to the present invention comprises an input shaft 9 connected to a drive shaft 7 of an engine 3 via a coupling 8; a pair of right and left output shafts 12 and 13 connected to the right and left propeller shafts 5 and 6 via couplings 10 and 11, respectively; a gear train comprised of gears 20 to 30 for transmitting the power of the input shaft 9 to each of the output shafts 12 and 13 through clutch mechanisms 14, 15, 16 and 17, and causing the output shafts to undergo forward or reverse rotation in response to switching between forward and reverse rotation clutch mechanisms; and a gear case 4 for containing the input shaft 9, the output shafts 12 and 13, the gear train of gears 20 to 30, and the forward and reverse rotation clutch mechanisms 14 to 17.

Abstract: A shift system for outboard motors, which is reduced in size, and is capable securing compatibility with an outboard motor of a type for which the shift operation is manually performed using a shift cable. A motor-driven shift actuator is disposed at a location forward of and to the right of an engine within an engine cover covering the engine. A clutch motor is provided for the actuator and disposed at a location rearward thereof, with a motor output shaft disposed in a manner extending forward, and is operated in response to the detected vessel operator's shift. An actuator output shaft is disposed at a location forward of the clutch motor and extends downward from a front part of the actuator. The actuator output shaft rotates in accordance with rotation of the motor output shaft. A clutch shaft is disposed below the actuator and rearward of the actuator output shaft.

Abstract: An outboard drive includes a prime mover having an output shaft. A driveshaft is coupled with the output shaft. Both shafts having axes that extend at least generally parallel to each other. A propulsion device is coupled with the driveshaft. The prime mover rotates the output shaft to drive the propulsion device through the driveshaft. A speed change mechanism is positioned between the output shaft and the driveshaft. The speed change mechanism changes a rotational speed of the output shaft transmitted to the driveshaft.

Abstract: A vertical fluid power transmission includes: a vertical crankshaft of an engine; a vertical output shaft; and a vertical torque converter disposed between the crankshaft and the output shaft. An oil supply passage is connected to one end of the circulation circuit of the vertical torque converter, and guides a stored oil that is drawn up from an oil tank and discharged by an oil pump. An oil return passage is connected to the other one end of the circulation circuit, and leads to the oil tank. A normally-closed pressure response valve is provided in the oil return passage. The pressure response valve is opened by an upstream pressure. Thus, the oil tank for storing a working oil of the torque converter is separated from the torque converter, thereby downsizing the torque converter, and the working oil is circulated between the oil tank and the circulation circuit of the torque converter, thereby promoting cooling of the working oil.

Abstract: A shift cutout control system is provided that can comprise a shift mechanism, an engine electronic control unit, a remote controller, and an ignition control means. The shift mechanism can switch a rotation of a propeller shaft into one of a neutral, forward, and reverse drive state. The propeller shaft can be driven by an output power of an engine. The engine electronic control unit can control a drive state of the engine. The remote controller can transmit a control signal to the engine electronic control unit to achieve a target drive state. The ignition control means can initiate an ignition cutout in the engine when an operating position signal from a lever position detector indicates that a control lever is in a neutral position and a shift position signal from a shift position detector indicates that a shift position is not in neutral.

Abstract: This boat drive system includes a primary and first and second outboard gearboxes. A drive shaft is connected between the engine and the primary gearbox and parallel shafts are connected between each outboard gearbox and a pair of first and second stern drive units mounted to the transom. The drive system also includes a cooling system provided by cooling pads operatively connected to each gearbox.

Abstract: A forward and reverse drive switching device for an outboard motor can include a switching mechanism that is actuated so as to set a propeller to a forward drive mode or a reverse drive mode. An actuator can have an electric motor and can serve as a drive source for the switching mechanism. A coupling member can transmit a driving force from the actuator to the switching mechanism to actuate the switching mechanism. The coupling member can include a rod disposed on an axis of the electric motor and can have an end coupled to the switching mechanism with its other end coupled to the electric motor to permit retracting and extending movements of the rod along the axis through the operation of the electric motor.