Patent Description:
The following U. Patents are presented.

<CIT> discloses an apparatus is for supporting an outboard motor on a transom of a marine vessel. The apparatus has a transom bracket configured for fixed attachment to the transom; a supporting cradle that supports the outboard motor with respect to the transom bracket, wherein the supporting cradle is pivotable with respect to the transom bracket about a trim axis; and a trim actuator that is pivotally coupled to the transom bracket at a first trim actuator pivot axis and to the supporting cradle at a second trim actuator pivot axis. Extension of the trim actuator pivots the supporting cradle upwardly about the trim axis. Retraction of the trim actuator pivots the supporting cradle downwardly about the trim axis. The trim axis is located aftwardly of the first trim actuator pivot axis.

<CIT> discloses a system for mounting an outboard motor propulsion unit to a marine vessel transom. The propulsion unit's midsection has an upper end supporting an engine system and a lower end carrying a gear housing. The mounting system includes a support cradle having a head section coupled to a transom bracket, an upper structural support section extending aftward from the head section and along opposite port and starboard sides of the midsection, and a lower structural support section suspended from the upper structural support section and situated on the port and starboard sides of the midsection. A pair of upper mounts couples the upper structural support section to the midsection proximate the engine system. A pair of lower mounts couples the lower structural support section to the midsection proximate the gear housing. At least one of the upper and lower structural support sections comprises an extrusion or a casting.

<CIT> discloses an assembly for mounting an outboard motor to a transom of a marine vessel. A support structure is configured to be coupled to the transom by a plurality of fasteners that extend through the support structure and through a set of holes that have been drilled in the transom. A steering head is coupled to the support structure and configured to support an outboard motor thereupon for rotation about a generally vertical steering axis. The set of holes is divided by a generally vertical fore-aft central plane, and the outboard motor extends along a generally vertical fore-aft central plane. The support structure and the steering head are coupled to one another such that the central plane of the outboard motor is capable of being laterally offset from the central plane of the set of holes. An assembly for mounting two or more outboard motors is also provided.

Document <CIT> discloses means for mounting and controlling an electric motor propeller unit in connection with a small boat.

Document <CIT> discloses an outboard motor for a marine vessel having an upper portion adapted to be affixed to a hull of an associated water craft.

Document <CIT> discloses an outboard motor for a small boat which has a concentric shaft and column and a steering motor.

Document <CIT> discloses an outboard motor for a boat, the outboard motor having a motor housing that is preferably streamlined.

This Summary is provided to introduce a selection of concepts which are further described herein below in the Detailed Description. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting scope of the claimed subject matter.

In examples disclosed herein, a marine drive comprises a supporting frame for coupling the marine drive to a marine vessel; a gearcase configured for supporting a propulsor for propelling the marine vessel in water; an extension leg disposed between the supporting frame and the gearcase, an adapter plate between the supporting frame and the extension leg; and a tube in the extension leg, the tube having an upper end and a lower end, wherein the lower end is rigidly coupled to the gearcase. A compression nut directly or indirectly couples the upper end of the tube to the supporting frame, in particular so as to clamp the extension leg in place between the supporting frame and the gearcase. The extension leg comprises a perimeter sidewall, the adapter plate comprises a perimeter sidewall, and the gearcase comprises an upwardly-facing gearcase housing portion having a perimeter sidewall, and wherein the perimeter sidewall of the extension leg is clamped between perimeter sidewall of the adapter plate and the perimeter sidewall of the upwardly-facing gearcase housing portion. A radially outer profile of the lower end of the extension leg generally matches a radially outer profile of an upper end of the upwardly-facing gearcase housing portion, and a radially outer profile of the upper end of the extension leg generally matches a radially outer profile of the perimeter sidewall of the adapter plate, such that the extension leg, the upwardly-facing gearcase housing portion and the adapter plate together provide a smooth outer surface which is streamlined and encounters minimal hydrodynamic drag as the marine vessel travels through the water.

In further non-limiting examples, the compression nut is engaged with the tube by a threaded connection such that rotating the compression nut relative to the tube in a first direction causes the compression nut to travel downwardly along the tube and such that rotating the compression nut relative to the tube in an opposite, second direction causes the compression nut to travel upwardly along the tube.

In further non-limiting examples, the tube extends through the adapter plate, and rotating the compression nut relative to the tube in the first direction moves the compression nut into compressing engagement with the adapter plate, which in turn clamps the extension leg between the adapter plate and the gearcase. Rotating the compression nut relative to the tube in the second direction moves the compression nut out of compressing engagement with the adapter plate, which in turn unclamps the extension leg relative to the adapter plate and the gearcase.

In further non-limiting examples, the adapter plate comprises an abutment surface disposed around the tube, wherein rotating the compression nut relative to the tube in the first direction moves the compression nut onto the abutment surface, which thereby clamps the extension leg between the adapter plate and the gearcase.

In further non-limiting examples, the extension leg comprises a perimeter sidewall, the adapter plate comprises a perimeter sidewall, and the gearcase comprises an upwardly-facing gearcase housing portion having a perimeter sidewall. The perimeter sidewall of the extension leg is clamped between perimeter sidewall of the adapter plate and the perimeter sidewall of the upwardly-facing gearcase housing.

In further non-limiting examples, an anti-ventilation plate which is sandwiched between the extension leg and the upper opening of the gearcase.

In further non-limiting examples, a motor is in the gearcase, the motor being configured to rotate the propulsor, and the tube provides a passageway for electrical connectors extending into the gearcase for connection to the motor.

In further non-limiting examples, a marine drive comprises a supporting frame for coupling the marine drive to a marine vessel; a gearcase supporting a propulsor for propelling the marine vessel in water; an extension leg disposed between the supporting frame and the gearcase; an adapter plate between the supporting frame and the extension leg; and a tube in the extension leg, the tube having a lower end which is coupled to the gearcase and upper end which is coupled to the adapter plate by a compression nut threaded onto the tube, wherein threading the compression nut down on the tube compressively engages the compression nut with the adapter plate, which in turn clamps the extension leg between the supporting frame and the gearcase.

The above examples are contemplated by the present disclosure in various combinations as further described herein below.

Examples are described with reference to the following drawing figures. The same numbers are used throughout to reference like features and components.

During research and development in the field of marine drives, the present inventors determined it is desirable to reconfigure the lower unit of a marine drive, such as an outboard marine drive, an inboard marine drive, or a stern drive, preferably so as to increase overall load carrying capability, and also preferably so as to avoid the use of externally visible fasteners, thus providing a more durable and visually appealing product. The present disclosure is a result of the present inventors' efforts in this regard.

The invention described herein below has been found to be particularly useful in configurations of marine drives having an electric motor located in a lower gearcase and being configured to power a propulsor, such as one or more propeller(s), impeller(s), and/or the like. The illustrated embodiment is just one example of such a marine drive; however the present invention is not limited for use with the illustrated configuration, and in other examples the present invention can be implemented in differently configured marine drives having an internal combustion engine, a hybrid-electric powerhead, and/or the like. The particular configurations of the marine drive shown and described herein below, including the supporting frame, electric motor, and gearcase, are merely exemplary. The present invention is also useful in conjunction with many other marine drive configurations.

<FIG> depicts a marine drive <NUM> for propelling a marine vessel in water. <FIG> depicts only lower portions of the marine drive <NUM>. Although not shown, the marine drive <NUM> also has upper portions, for example one or more upper cowling member(s) which cover an upper supporting frame portion, and/or other conventional apparatuses for supporting various electrical and mechanical components of the marine drive <NUM>. Although not shown, the marine drive <NUM> is attachable to the marine vessel via for example a conventional transom bracket and/or the like. Some examples of suitable arrangements are provided in the above-described patents, and others are widely commercially available for purchase from Brunswick Corporation and its companies Attwood and Mercury Marine, among others.

In the illustrated embodiment, the marine drive <NUM> extends from top to bottom in an axial direction AX, from front to back in a longitudinal direction LO which is perpendicular to the axial direction AX, and from side to opposite side in a lateral direction LA which is perpendicular to the axial direction AX and perpendicular to the longitudinal direction LO.

As shown, the marine drive <NUM> has a lower unit <NUM> comprised of a supporting frame <NUM>, a gearcase <NUM>, an extension leg <NUM> which is located axially between the supporting frame <NUM> and the gearcase <NUM>, an adapter plate <NUM> which is located between the extension leg <NUM> and the supporting frame <NUM>, and an anti-ventilation plate <NUM> which is located axially between the extension leg <NUM> and the gearcase <NUM>, and extending rearwardly therefrom.

The upper portions of the supporting frame <NUM> are not shown in the figures because the type and configuration of the supporting frame <NUM> can vary. The present invention is not limited for use with a particular type of supporting frame. The supporting frame <NUM> can be any type of supporting frame known in the art for framing and supporting portions of the marine drive, including being configured to support various components of the marine drive, and/or to couple the marine drive to the marine vessel. Examples of various suitable supporting frames for marine drives are provided in the above-described patents.

Referring to <FIG>, the lower end of the supporting frame <NUM> has a radial flange <NUM> which extends from and around the perimeter of the perimeter sidewall <NUM> of the supporting frame <NUM>. The sidewall <NUM> of the supporting frame defines an interior passage <NUM>. Fasteners <NUM> extend through bores in the radial flange <NUM> and into engagement with bores in the perimeter sidewall <NUM> of the adapter plate <NUM>. Thus the fasteners <NUM> fasten the supporting frame <NUM> to the adapter plate <NUM>.

The gearcase <NUM> has a front gearcase housing <NUM> and a rear gearcase housing <NUM>, which together define a gearcase cavity <NUM> containing an electric motor <NUM>. The front gearcase housing <NUM> has a nosecone <NUM> with a smooth outer surface which transitions to an upwardly-facing gearcase housing portion <NUM> and a downwardly-extending skeg <NUM>. The upwardly-facing gearcase housing portion <NUM> has a perimeter sidewall <NUM> which preferably is monolithic so as to avoid visible fasteners or unsightly seams, or can be made of multiple pieces. The nosecone <NUM> is generally located axially between the upwardly-facing gearcase housing portion <NUM> and the skeg <NUM>, and protrudes forwardly therefrom. The front gearcase housing <NUM> further has a rear-facing gearcase housing portion <NUM> which receives the rear gearcase housing <NUM> in a nested configuration. O-ring seals <NUM> are disposed therebetween for limiting water intrusion into the gearcase cavity <NUM>.

The rear gearcase housing <NUM> has a radially outer flange <NUM>. Fasteners <NUM> extend through bores in the radially outer flange <NUM> and into threaded engagement with corresponding bores in the front gearcase housing <NUM>, so as to fasten the rear gearcase housing <NUM> to the front gearcase housing <NUM>, as shown in a nested arrangement. The rear gearcase housing <NUM> is generally cylindrical and has a perimeter sidewall <NUM> which smoothly tapers, radially inwardly at its rear end. The electric motor <NUM> is also generally cylindrical and is contained within the rear gearcase housing <NUM>, in particular being mounted between a rear end cap <NUM> and a front end wall <NUM> of the rear gearcase housing <NUM>. The electric motor <NUM> causes rotation of an output shaft <NUM> which longitudinally extends from the rear of the rear gearcase housing <NUM>, through the noted rear end cap <NUM>. The electric motor <NUM> can be a conventional item, for example an axial flux motor, a radial flux motor, or a transverse flux motor, such as those produced by Electric Torque Machines of Flagstaff, Arizona (a Graco Company). Front and rear bearings <NUM>, <NUM> support rotation of the output shaft <NUM> relative to the electric motor <NUM>. A conventional propeller (not shown) is mounted on the outer end of the output shaft <NUM> such that rotation of the output shaft <NUM> by the electric motor <NUM> causes rotation of the propeller, which in turn generates a thrust force for propelling the marine vessel in water.

Referring to <FIG> and <FIG>, the anti-ventilation plate <NUM> has a head <NUM> at its forward end which is sandwiched between the extension leg <NUM> and the upwardly-facing gearcase housing portion <NUM> of the front gearcase housing <NUM>. The head <NUM> has a tear-drop shaped perimeter sidewall <NUM> having a rounded forward end. The perimeter sidewall <NUM> is preferably monolithic so as to avoid external fasteners or other unsightly seams, or in other examples can be made of multiple pieces. The radially outer profile of the head <NUM> is foil-shaped or tear-drop shaped and generally matches the radially outer profile of the lower end of the extension leg <NUM> and also generally matches the radially outer profile of the upper end of the upwardly-facing gearcase housing portion <NUM>, such that these components together provide a smooth outer surface which is streamlined and encounters minimal hydrodynamic drag as the marine vessel travels through the water. Dowel pins <NUM> register and maintain the head <NUM> of the anti-ventilation plate <NUM> in alignment with the upwardly-facing gearcase housing portion <NUM> and the lower end of the extension leg <NUM>. The dowel pins <NUM> extend through bores formed through the head <NUM> of the anti-ventilation plate <NUM> and into corresponding bores formed in the lower end of the extension leg <NUM> and corresponding bores the upper end of the upwardly-facing gearcase housing portion <NUM>. The anti-ventilation plate <NUM> has a generally flat tail <NUM> which extends rearwardly from the head <NUM>. The tail <NUM> extends rearwardly from both sides of the head <NUM>.

Referring to <FIG> and <FIG>, the extension leg <NUM> is a sleeve having the perimeter sidewall <NUM> which defines a hollow interior <NUM>. The sleeve is preferably monolithic to as to avoid externally visible fasteners or unsightly seam lines, or can be formed from multiple pieces. A hollow, axially-elongated tube <NUM> is located in the hollow interior <NUM>. The tube <NUM> has a lower end <NUM> which is fixedly coupled to the gearcase <NUM> and an upper end <NUM> which is coupled to the supporting frame <NUM> via a compression nut <NUM>, which will be further described herein below. In a non-limiting example, the tube <NUM> is a monolithic aluminum tube. The hollow interior of the tube <NUM> provides a passageway for electrical connectors <NUM> extending from an upper portion of the marine drive <NUM> to the gearcase cavity <NUM>, and for connection to the electric motor <NUM>, i.e., for providing electricity to the electric motor <NUM> and/or for controlling the electric motor <NUM>. The lower end <NUM> of the tube <NUM> is fixedly or rigidly coupled to the gearcase <NUM> by a threaded connection <NUM> comprising outer threads <NUM> on the outer diameter of the tube <NUM> and inner threads <NUM> on the inner diameter of a cylindrical stack <NUM> extending upwardly from a bottom wall <NUM> of the upwardly-facing gearcase housing portion <NUM>. O-ring seals <NUM> provide a water-tight seal between the outer diameter of the tube <NUM> and the inner diameter of the cylindrical stack <NUM>. A radially outer shoulder <NUM> on the lower end <NUM> of the tube <NUM> bottoms out on a radially inner shoulder <NUM> in the cylindrical stack <NUM> when the threaded connection <NUM> is fully engaged. The outer diameter of the tube <NUM> at the upper end <NUM> has flat surfaces <NUM> for engagement by a manual tool during installation, in particular for rotating the upper end <NUM> of the tube <NUM> relative to the gearcase <NUM> so as to complete the threaded connection <NUM>.

The sidewall <NUM> of the adapter plate <NUM> has a radially outer profile that generally matches the radially outer profile of the upper end of the extension leg <NUM>, in particular such that these components together provide a smooth outer surface which is streamlined and provides minimal hydrodynamic drag as the marine vessel travels through the water. Dowel pins <NUM> register and maintain the adapter plate <NUM> in alignment with upper end of the extension leg <NUM>. The dowel pins <NUM> extend into bores formed in the perimeter sidewall of the adapter plate <NUM> and into corresponding bores formed in the perimeter sidewall of the upper end of the extension leg <NUM>. The adapter plate <NUM> has an interior abutment surface <NUM> that laterally and longitudinally extends between the inner diameter of the sidewall <NUM> of the adapter plate <NUM>. As best seen in <FIG>, the upper end <NUM> of the tube <NUM> axially extends out of the hollow interior <NUM> of the extension leg <NUM>, through a hole in the interior abutment surface <NUM>, and protrudes the interior passage <NUM> of the supporting frame <NUM>. The interior abutment surface <NUM> extends entirely around the tube <NUM>.

The noted compression nut <NUM> is engaged with the upper end <NUM> of the tube <NUM> via a threaded connection <NUM>, and particularly as further explained herein below so as to clamp the extension leg <NUM> in place between the supporting frame <NUM> and the gearcase <NUM>, thereby providing increased overall load carrying capability compared to the prior art and avoiding the use of fasteners that are visible from the exterior of the lower unit. The outer diameter of the upper end <NUM> of the tube <NUM> has threads <NUM>. The inner diameter of the compression nut <NUM> has corresponding threads <NUM> for engaging the threads <NUM>. Flats <NUM> are disposed around the outer perimeter of the compression nut <NUM> for engagement by a manual tool for rotating the compression nut <NUM> about the tube <NUM>.

To assemble the lower unit, a washer <NUM> and the compression nut <NUM> are slid onto the upper end <NUM> of the tube <NUM> until the threads <NUM> engage the threads <NUM>. The compression nut <NUM> is then rotated in the direction that causes the compression nut <NUM> to travel downwardly along the tube <NUM>, via engagement between the threads <NUM>, <NUM>. Continued rotation of the compression nut <NUM> moves the compression nut <NUM> into compressing engagement with the top of the interior abutment surface <NUM> of the adapter plate <NUM>. Thus, rotation of the compression nut <NUM> applies a compression force on the adapter plate <NUM>, which in turn pulls the tube <NUM> and gearcase <NUM> axially upwardly. This firmly compresses and clamps the head <NUM> of the anti-ventilation plate <NUM> and the extension leg <NUM> between the gearcase <NUM> and bottom of the adapter plate <NUM> without the need for external fasteners and in an improved load-bearing arrangement. Advantageously the entire arrangement can be easily assembled in an efficient manner.

It will thus be understood that the present disclosure provides improved embodiments of marine drives comprising a supporting frame for coupling the marine drive to a marine vessel; a gearcase supporting a propulsor for propelling the marine vessel in water; an extension leg disposed between the supporting frame and the gearcase; and a tube in the extension leg, the tube having an upper end and a lower end, wherein the lower end is rigidly coupled to the gearcase. A compression nut advantageously directly or indirectly couples the upper end of the tube to the supporting frame, in particular so as to clamp the extension leg in place between the supporting frame and the gearcase. The compression nut is engaged with the tube by a threaded connection such that rotating the compression nut relative to the tube in a first direction causes the compression nut to travel downwardly along the tube and such that rotating the compression nut relative to the tube in an opposite, second direction causes the compression nut to travel upwardly along the tube. An adapter plate is located between the supporting frame and the extension leg. The tube extends through the adapter plate. Rotating the compression nut relative to the tube in the first direction moves the compression nut into compressing engagement with the adapter plate, which in turn clamps the extension leg between the adapter plate and the gearcase. Rotating the compression nut relative to the tube in the second direction moves the compression nut out of compressing engagement with the adapter plate, which in turn unclamps the extension leg relative to the adapter plate and the gearcase.

The adapter plate comprises an abutment surface disposed around the tube, wherein rotating the compression nut relative to the tube in the first direction moves the compression nut onto the abutment surface, which thereby clamps the extension leg between the adapter plate and the gearcase. The extension leg comprises a perimeter sidewall, the adapter plate comprises a perimeter sidewall, and the gearcase comprises an upwardly-facing gearcase housing portion having a perimeter sidewall. The perimeter sidewall of the extension leg is clamped between perimeter sidewall of the adapter plate and the perimeter sidewall of the upwardly-facing gearcase housing. Preferably the respective sidewalls are monolithic sleeves that do not have externally visible fasteners or seams, thus providing an aesthetically pleasing appearance in a hydrodynamically effective package that is easy to assemble, and which also has improved load-bearing stability over other embodiments in the prior art.

An anti-ventilation plate is sandwiched between the extension leg and the upper opening of the gearcase. A motor in the gearcase, the motor being configured to rotate the propulsor. The tube provides a passageway for electrical connectors extending into the gearcase for connection to the motor. The lower end of the tube is fixed to the gearcase by a threaded connection comprising outer threads on the tube and inner threads on the gearcase.

In certain examples, the extension leg is a monolithic sleeve and the tube in the extension leg is a monolithic aluminum tube.

Claim 1:
A marine drive (<NUM>) comprising:
a supporting frame (<NUM>) for coupling the marine drive (<NUM>) to a marine vessel;
a gearcase (<NUM>) configured for supporting a propulsor for propelling the marine vessel in water;
an extension leg (<NUM>) disposed between the supporting frame (<NUM>) and the gearcase (<NUM>);
an adapter plate (<NUM>) between the supporting frame (<NUM>) and the extension leg (<NUM>);
a tube (<NUM>) in the extension leg (<NUM>), the tube (<NUM>) having an upper end (<NUM>) and a lower end (<NUM>), wherein the lower end (<NUM>) is rigidly coupled to the gearcase (<NUM>); and
a compression nut (<NUM>) which directly or indirectly couples the upper end (<NUM>) of the tube (<NUM>) to the supporting frame (<NUM>), in particular so as to clamp the extension leg (<NUM>) in place between the supporting frame (<NUM>) and the gearcase (<NUM>);
wherein the extension leg (<NUM>) comprises a perimeter sidewall (<NUM>), the adapter plate (<NUM>) comprises a perimeter sidewall (<NUM>), and the gearcase (<NUM>) comprises an upwardly-facing gearcase housing portion (<NUM>) having a perimeter sidewall (<NUM>), and wherein the perimeter sidewall of the extension leg (<NUM>) is clamped between the perimeter sidewall (<NUM>) of the adapter plate (<NUM>) and the perimeter sidewall (<NUM>) of the upwardly-facing gearcase housing portion (<NUM>);
wherein a radially outer profile of the lower end of the extension leg (<NUM>) generally matches a radially outer profile of an upper end of the upwardly-facing gearcase housing portion (<NUM>), and a radially outer profile of the upper end of the extension leg (<NUM>) generally matches a radially outer profile of the perimeter sidewall (<NUM>) of the adapter plate (<NUM>), such that the extension leg (<NUM>), the upwardly-facing gearcase housing portion (<NUM>) and the adapter plate (<NUM>) together provide a smooth outer surface which is streamlined and encounters minimal hydrodynamic drag as the marine vessel travels through the water.