US20140373769A1

US20140373769A1 - Watercraft hull

Info

Publication number: US20140373769A1
Application number: US14/483,427
Authority: US
Inventors: Sam Spade; Rick Adamczyk; Lonnie Lieb
Original assignee: Bombardier Recreational Products Inc
Current assignee: Bombardier Recreational Products Inc
Priority date: 2010-04-30
Filing date: 2014-09-11
Publication date: 2014-12-25
Also published as: USD865634S1; US20110265705A1

Abstract

A hull for a watercraft has a port side, a starboard side, and a keel disposed between the port side and the starboard side. Each of the port and starboard sides has a first portion having a first deadrise angle, and a second portion having a second deadrise angle. The first portion is disposed laterally between the second portion and the keel. A first chine is connected to the first portion. The first portion is disposed laterally between the keel and the first chine. A second chine is connected to the second portion. The second portion is disposed laterally between the first chine and the second chine. The second chine is a soft chine. The first chine has a smaller radius of curvature than the second chine.

Description

TECHNICAL FIELD

The present invention relates to hulls for watercraft.

BACKGROUND

Watercraft for buoy courses have hulls designed to plane (or glide) on the water at high speeds and to lean the watercraft sideways, such as during a sharp turn around a buoy. Typically, in a buoy course, when engaging into a turn, the driver of the watercraft leans the watercraft and uses his momentum to glide around the buoy. The more the driver can lean, the sharper his turn will be.
To allow leaning, buoy course watercraft have hulls with a high deadrise angle. The deadrise angle is the angle formed between the hull or a portion of the hull and the horizontal. Hulls which have such deadrise angles have less surface area contact with the water which is beneficial for drag reduction. However, because a hull with a high deadrise angle shifts the center of gravity of the watercraft upwards, a watercraft with a high deadrise angle is usually less stable than a similar watercraft with a low deadrise angle. Watercraft with high deadrise angles allow the driver to lean more and thus, to provide more lateral force, or sharper cornering capability. However, there is a threshold to how much the driver can lean his watercraft before the watercraft looses grip with the water and begin sliding sideways. Hulls with high deadrise angles have a higher threshold leaning angle than hulls with low deadrise angles. As a consequence, to avoid losing grip, the driver adapts his driving by typically engaging the turn early on and turns at a wide angle around the buoy and turns using inertia momentum.
To address this trade-off between cornering capability and watercraft stability, planning type hulls have been designed as double deadrise hulls. In a double deadrise hull, the bottom part of the hull has a high deadrise angle, and the top part of the hull has a low deadrise angle. Therefore, in a double deadrise hull, the bottom portion is narrow and high to allow leaning at high speed, while the top portion is wide and low for increase stability at low speed. The vertical distance between the two portions also allows for increased leaning/banking capability.
The different portions of the hull (having same or different deadrise angles) are connected to each other by chines. Chines are the corners (or vertex) between these different portions. Among the different types of chines, chines can be designed as soft chines or hard chines. A soft chine is a chine that has a large radius of curvature, and that give a smooth ride. A hard chine is a chine that has a small radius of curvature or is even a sharp corner. When there is a hard chine, the sharp transition between the two portions of the hull causes water separation, which is advantageous for reducing drag. However, during buoy course at the time of cornering a buoy, water separation is not desirable as it promotes potential sideways sliding. The current double deadrise hulls have a hard chine at an upper part of the hull which limits the corning capability. In addition, in high wave condition, hard chines act against the hull penetration is water.
Therefore, there is a need for a watercraft that would permit fast and sharp cornering while being stable.

SUMMARY

It is an object of the present invention to ameliorate at least some of the inconveniences present in the prior art.
It is also an object of the present invention to provide a hull for a watercraft. The hull comprises a port side, a starboard side, and a keel disposed between the port side and the starboard side. Each of the port and starboard sides comprises a first portion having a first deadrise angle, and a second portion having a second deadrise angle. The first portion is disposed laterally between the second portion and the keel. A first chine is connected to the first portion. The first portion is disposed laterally between the keel and the first chine. A second chine is connected to the second portion. The second portion is disposed laterally between the first chine and the second chine. The second chine is a soft chine.
The hull of the present invention is a double deadrise hull which provides leaning capabilities at high speeds during planning, and also stable ride in non-planning conditions. At low speeds (typically below 30 mph for a personal watercraft (PWC)) where the watercraft is non-planning (sometimes referred as water displacement mode), both first and second portions of the hull are immerged and the hull displaces the water for supporting the weight of the watercraft. The watercraft is stable which is desirable when docking or maneuvering through a marina for example, where there is high watercraft traffic and little space to maneuver. At high speeds (typically above 30 mph for a PWC), when in straight line or in moderate turn conditions, the watercraft glides on the first portion of the hull (lower portion).
Because only the first portion of the hull is in contact with the water, less drag is produced than when the first and second portions are in contact with the water.
Contrarily of the prior art, the hull of the present invention has a soft second chine (i.e. chine at the upper part of the hull). The soft chine comes in contact with the water at high leaning angles and does not promote water separation. As a consequence, the soft chine allows for a greater threshold leaning angle.
The soft chine retains the water flow at the boundary layer. The retained water creates a downward hydrostatic force on the bow and the front sides of the watercraft when the driver slightly releases the throttle to allow the bow of the hull to dive slightly. This downward force acts as a pivot point for the hull to corner without losing much of its speed.
In an additional aspect, the chine is a hard chine.
The hard chine provides water separation between the first portion and the second portion of the hull.
In a further aspect, the hull has a length. For each of the port and starboard sides, the first and second chines extend parallel to each other on at least a portion of the length of the hull.
In an additional aspect, for each of the port and starboard sides at least one of the first and second portions is uninterrupted.
In a further aspect, for each of the port and starboard sides, the first portion comprises at least one lifting strake. Lifting strakes are used to peel water away from the hull around the waterline in order to decrease the area of the hull in contact with the water and thus reduces drag.
In an additional aspect, for each of the port and starboard sides, the first deadrise angle and the second deadrise angle are identical.
In a further aspect, for each of the port and starboard sides, at least one of the first and second chines is uninterrupted and extends on a majority of a length of the hull.
In an additional aspect, for each of the port and starboard sides, when seen from the port and starboard sides, at least one of the first and second chines is generally parallel to a waterline of the hull.
In a further aspect, the hull further comprises a port sponson connected to the port side, and a starboard sponson connected to the starboard side.
In an additional aspect, for each of the port and starboard sides, the hull further comprises a third portion and a third chine. The first chine connects the third portion to the first portion. The third chine connects the third portion to the second portion. The third portion has a third deadrise angle. The third deadrise angle is different from the first and second deadrise angles.
In a further aspect, for each of the port and starboard sides, a reverse chine is connected to the second chine. The second chine is disposed laterally between the second portion and the reverse chine. The reverse chines are used to produce additional lift for easier planning.
In another aspect, the invention provides a watercraft comprising a hull and a deck disposed on the hull. The hull has port and starboard sides and a keel disposed therebetween. An engine is connected to at least one of the hull and the deck. A propulsion system is operatively connected to the engine. Each of the port and starboard sides comprises a first portion having a first deadrise angle, and a second portion having a second deadrise angle. The first portion is disposed laterally between the second portion and the keel. A first chine is connected to the first portion. The first portion is disposed laterally between the keel and the first chine. A second chine is connected to the second portion. The second portion is disposed laterally between the first chine and the second chine. The second chine is a soft chine.
In an additional aspect, for each of the port and starboard sides, the first chine is a hard chine.
In a further aspect, the watercraft has a length. For each of the port and starboard sides, the first and second chines extend parallel to each other on at least a portion of the length of the hull.
In an additional aspect, for each of the port and starboard sides, at least one of the first and second portions is uninterrupted.
In a further aspect, for each of the port and starboard sides, the first portion comprises at least one lifting strake.
In an additional aspect, for each of the port and starboard sides, the first deadrise angle and the second deadrise angle are identical.
In a further aspect, for each of the port and starboard sides, at least one of the first and second chines is uninterrupted and extends on a majority of a length of the hull.
In an additional aspect, for each of the port and starboard sides, when seen from the port and starboard sides, at least one of the first and second chines is generally parallel to a waterline of the hull.
In a further aspect, the watercraft further comprises a port sponson connected to the port side, and a starboard sponson connected to the starboard side.
In an additional aspect, for each of the port and starboard sides, the hull further comprises a third portion and a third chine. The first chine connects the third portion to the first portion. The third chine connects the third portion to the second portion. The third portion has a third deadrise angle. The third deadrise angle is different from the first and second deadrise angles.
In a further aspect, for each of the port and starboard sides, the hull further comprises a reverse chine connected to the second chine. The second chine is disposed laterally between the second portion and the reverse chine.
In yet another aspect, the present invention provides a hull for a watercraft. The hull comprises a port side, a starboard side, and a keel disposed between the port side and the starboard side. Each of the port and starboard sides comprises a first portion having a first deadrise angle, and a second portion having a second deadrise angle. The first portion is disposed laterally between the second portion and the keel. A first chine is connected to the first portion. The first portion is disposed laterally between the keel and the first chine. A second chine is connected to the second portion. The second portion is disposed laterally between the first chine and the second chine. The first chine has a smaller radius of curvature than the second chine.
For the purposes of this application, the term ‘deadrise angle’ refers to the angle formed between a portion of the hull and the horizontal when the hull is level. If the portion is curved, the deadrise angle is the average angle of that portion. The term ‘chine’ refers to the connection between two portions of the hull having different orientations. A chine is called ‘reverse chine’ when the chine protrudes from the hull and is downwardly with respect to a waterline. A chine is called ‘flat chine’ when the chine protrudes from the hull and goes parallel to the waterline. The term ‘hard chine’ refers to a chine forming in the hull a sharp or a blunt edge with a small radius of curvature. The term ‘soft chine’ refers to a chine forming in the hull a blunt edge with a large radius of curvature. The term ‘strake’ refers to a protruding portion of the hull. The term ‘keel’ refers to a structural element located at a lowest most part of the hull. The term ‘waterline’ refers to the line on the hull of a watercraft where the water comes to, when the watercraft is unloaded, at rest and level.
Embodiments of the present invention each have at least one of the above-mentioned objects and/or aspects, but do not necessarily have all of them. It should be understood that some aspect of the present invention that have resulted from attempting to attain the above-mentioned objects may not satisfy these objects and/or may satisfy other objects not specifically recited herein.
Additional and/or alternative features, aspects, and advantages of the embodiments of the present invention will become apparent from the following description, the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention, as well as other aspects and further features thereof, reference is made to the following description which is to be used in conjunction with the accompanying drawings, where:

FIG. 1 illustrates a left side elevation view of a personal watercraft having a hull according to an embodiment of the invention;

FIG. 2 is a top plan view of the watercraft of FIG. 1;

FIG. 3 is a perspective view, taken from a front, left side, of a jet boat having a hull according to an embodiment of the invention;

FIG. 4 is a perspective view, taken from a rear, left side, of the jet boat of FIG. 3;

FIG. 5 a perspective view, taken from a bottom, rear, left side, of the hull of the personal watercraft of FIG. 1;

FIG. 6 is a left side elevation view of the hull of FIG. 5;

FIG. 7 is a transversal cross-sectional view of the hull taken along line 7-7 in FIG. 6;

FIG. 8 is a transversal cross-sectional view of the hull taken along line 8-8 in FIG. 6;

FIG. 9 is a transversal cross-sectional view of the hull taken along line 9-9 in FIG. 6;

FIG. 10 is a transversal cross-sectional view of the hull taken along line 10-10 in FIG. 6;

FIG. 11 is a transversal cross-sectional view of the hull taken along line 11-11 in FIG. 6; and

FIG. 12 is a front elevation view of the hull of FIG. 6.

DETAILED DESCRIPTION

The general construction of a personal watercraft 10 in accordance with this invention is shown in FIGS. 1 and 2. The following description relates to one way of manufacturing a personal watercraft. Obviously, those of ordinary skill in the watercraft art will recognize that there are other known ways of manufacturing and designing watercraft and that this invention would encompass these other known ways and designs.
The watercraft 10 of FIG. 1 is made of a hull 200 and a deck 14. The hull 200 buoyantly supports the watercraft 10 in the water. The deck 14 is designed to accommodate a rider and, in some watercraft, one or more passengers. The hull 200 and deck 14 are joined together at a seam 16 that joins the parts in a sealing relationship. Preferably, the seam 16 comprises a bond line formed by an adhesive. Of course, other known joining methods could be used to sealingly engage the parts together, including but not limited to thermal fusion, molding or fasteners such as rivets or screws. A bumper 18 generally covers the seam 16, which helps to prevent damage to the outer surface of the watercraft 10 when the watercraft 10 is docked, for example. The bumper 18 can extend around the bow, as shown, or around any portion or all of the seam 16. The hull 200, which is schematically shown in FIG. 1, has a width 262 (shown in FIG. 10) of 110 cm (43 inches) and a length 264 (shown in FIG. 6) of 325 cm (128 inches). Throughout this application, widths are measured with respect to a transverse direction of the hull 200 extending from port side 205 to starboard side 207, and lengths are measured with respect to a longitudinal direction of the hull 200, i.e. extending between the bow 202 and the aft 204. It is contemplated that the hull 200 could have a width 262 comprised between 101 and 127 cm (40 and 50 inches), and a length 262 comprises between 228 and 330 cm (90 and 130 inches). However, other widths and lengths are also contemplated. The hull 200 will be described in greater detail below with respect to FIGS. 5 to 12.
The space between the hull 200 and the deck 14 forms a volume commonly referred to as the engine compartment 20 (shown in phantom). The engine compartment 20 accommodates an engine 22, as well as a muffler, tuning pipe, gas tank, electrical system (battery, electronic control unit, etc.), air box, storage bins 24, 26, and other elements required or desirable in the watercraft 10.
As seen in FIGS. 1 and 2, the deck 14 has a centrally positioned straddle-type seat 28 positioned on top of a pedestal 30 to accommodate multiple riders in a straddling position. As seen in FIG. 2, the seat 28 includes a first, front seat portion 32 and a rear, raised seat portion 34. The seat 28 is preferably made as a cushioned or padded unit, or as interfitting units. The first and second seat portions 32, 34 are removably attached to the pedestal 30 by a hook and tongue assembly (not shown) at the front of each seat and by a latch assembly (not shown) at the rear of each seat, or by any other known attachment mechanism. The seat portions 32, 34 can be individually tilted or removed completely. Seat portion 32 covers an engine access opening defined by a top portion of the pedestal 30 to provide access to the engine 22. Seat portion 34 covers a removable storage bin 26. A “glove compartment” or small storage box 36 is provided in front of the seat 28.
A grab handle 38 is provided between the pedestal 30 and the rear of the seat 28 to provide a handle onto which a passenger may hold. This arrangement is particularly convenient for a passenger seated facing backwards for spotting a water skier, for example. Beneath the grab handle 38, a tow hook 40 is mounted on the pedestal 30. The tow hook 40 can be used for towing a skier or floatation device, such as an inflatable water toy.
The watercraft 10 has a pair of generally upwardly extending walls located on either side of the watercraft 10 known as gunwales or gunnels 42. The gunnels 42 help to prevent the entry of water in the footrests 46 of the watercraft 10, provide lateral support for the riders' feet, and also provide buoyancy when turning the watercraft 10, since personal watercraft roll slightly when turning. Towards the rear of the watercraft 10, the gunnels 42 extend inwardly to act as heel rests 44. A passenger riding the watercraft 10 facing towards the rear, to spot a water-skier for example, may place his or her heels on the heel rests 44, thereby providing a more stable riding position. Heel rests 44 could also be formed separately from the gunnels 42.
Located on both sides of the watercraft 10, between the pedestal 30 and the gunnels 42 are the footrests 46. The footrests 46 are designed to accommodate the riders' feet in various riding positions. To this effect, the footrests 46 each have a forward portion 48 angled such that the front portion of the forward portion 48 (toward the bow 202 of the watercraft 10) is higher than the rear portion of the forward portion 48. The remaining portions of the footrests 46 are generally horizontal. Of course, any contour conducive to a comfortable rest for the riders could be used. The footrests 46 are covered by carpeting 50 made of a rubber-type material, for example, to provide additional comfort and traction for the feet of the riders.
A reboarding platform 52 is provided at the rear of the watercraft 10 on the deck 14 to allow the rider or a passenger to easily reboard the watercraft 10 from the water. Carpeting or some other suitable covering may cover the reboarding platform 52. A retractable ladder (not shown) may be affixed to the transom 54 to facilitate boarding the watercraft 10 from the water onto the reboarding platform 52.
Referring to the bow 202 of the watercraft 10, the watercraft 10 is provided with a hood 58 located forwardly of the seat 28 and a helm assembly 60. A hinge (not shown) is attached between a forward portion of the hood 58 and the deck 14 to allow hood 58 to move to an open position to provide access to the front storage bin 24. A latch (not shown) located at a rearward portion of hood 58 locks hood 58 into a closed position. When in the closed position, hood 58 prevents water from entering front storage bin 24. Rearview mirrors 62 are positioned on either side of hood 58 to allow the rider to see behind the watercraft 10. A hook 64 (shown in FIG. 5) is located at the bow 202 of the watercraft 10. The hook 64 is used to attach the watercraft 10 to a dock when the watercraft 10 is not in use or to attach to a winch when loading the watercraft 10 on a trailer, for instance.
The helm assembly 60 is positioned forwardly of the seat 28. The helm assembly 60 has a central helm portion 72, that is padded, and a pair of steering handles 74, also referred to as a handlebar. One of the steering handles 74 is provided with a throttle operator 76, which allows the rider to control the engine 22, and therefore the speed of the watercraft 10. The throttle operator 76 can be in the form of a thumb-actuated throttle lever (as shown), a finger-actuated throttle lever, or a twist grip. The throttle operator 76 is movable between an idle position and multiple actuated positions. In a preferred embodiment, the throttle operator 76 is biased towards the idle position, such that, should the driver of the watercraft 10 let go of the throttle operator 76, it will move to the idle position. The other of the steering handles 74 is provided with a lever 75 used by the driver to decelerate the watercraft 10 as described in greater detail below.
As seen in FIG. 2, a display area or cluster 78 is located forwardly of the helm assembly 60. The display cluster 78 can be of any conventional display type, including a liquid crystal display (LCD), dials or LED (light emitting diodes). The central helm portion 72 has various buttons 80, which could alternatively be in the form of levers or switches, that allow the driver to modify the display data or mode (speed, engine rpm, time . . . ) on the display cluster 78 or to change a condition of the watercraft 10, such as trim (the pitch of the watercraft 10).
The helm assembly 60 is provided with a key receiving post (not shown) located near a center of the central helm portion 72. The key receiving post 82 is adapted to receive a key (not shown) that starts the watercraft 10. As is known, the key is typically attached to a safety lanyard (not shown). It should be noted that the key receiving post 82 may be placed in any suitable location on the watercraft 10.
The watercraft 10 is generally propelled by a jet propulsion system 84. As is known, the jet propulsion system 84 pressurizes water to create thrust. The water is first scooped from under the hull 200 through an inlet 86, which has an inlet grate (not shown in detail). The inlet grate prevents large rocks, weeds, and other debris from entering the jet propulsion system 84, which may damage the system or negatively affect performance. Water flows from the inlet 86 through a water intake ramp 88. The top portion 90 of the water intake ramp 88 is formed by the hull 200, and a ride shoe (not shown in detail) forms its bottom portion 92. Alternatively, the intake ramp 88 may be a single piece or an insert to which the jet propulsion system 84 attaches. In such cases, the intake ramp 88 and the jet propulsion system 84 are attached as a unit in a recess in the bottom of hull 200.
From the intake ramp 88, water enters a jet pump (not shown). The jet pump is located in a formation in the hull 200, referred to as the tunnel 94. The tunnel 94 is defined at the front, sides, and top by the hull 200 and is open at the transom 54. The bottom of the tunnel 94 is closed by a ride plate (not shown). The ride plate creates a surface on which the watercraft 10 rides or planes at high speeds.
The jet pump includes an impeller (not shown) and a stator (not shown). The impeller is coupled to the engine 22 by one or more shafts 98, such as a driveshaft and an impeller shaft. The rotation of the impeller pressurizes the water, which then moves over the stator that is made of a plurality of fixed stator blades (not shown). The role of the stator blades is to decrease the rotational motion of the water so that almost all the energy given to the water is used for thrust, as opposed to swirling the water. Once the water leaves the jet pump, it goes through a venturi (not shown). Since the venturi's exit diameter is smaller than its entrance diameter, the water is accelerated further, thereby providing more thrust. A steering nozzle 73 is pivotally attached to the venturi so as to pivot about a vertical axis 71. The steering nozzle 73 could also be supported at the exit of the tunnel 94 in other ways without a direct connection to the venturi. Moreover, the steering nozzle 73 can be replaced by a rudder or other diverting mechanism disposed at the exit of the tunnel 94 to selectively direct the thrust generated by the jet propulsion system 84 to effect turning.
The steering nozzle 73 is operatively connected to the helm assembly 60 preferably via a push-pull cable (not shown) such that when the helm assembly 60 is turned, the steering nozzle 73 pivots. This movement redirects the pressurized water coming from the venturi, so as to redirect the thrust and steer the watercraft 10 in the desired direction. Optionally, the steering nozzle 73 may be gimbaled to allow it to move around a second horizontal pivot axis (not shown). The up and down movement of the steering nozzle 73 provided by this additional pivot axis is known as trim and controls the pitch of the watercraft 10.
When the watercraft 10 is moving, its speed is measured by a speed sensor (not shown) attached to the transom 54 of the watercraft 10. The speed sensor has a paddle wheel (not shown) that is turned by the water flowing past the hull 200. In operation, as the watercraft 10 goes faster, the paddle wheel also turns faster. An electronic control unit (ECU) (not shown) connected to the speed sensor converts the rotational speed of the paddle wheel to the speed of the watercraft 10 in kilometers or miles per hour, depending on the rider's preference. The speed sensor may also be placed in the ride plate or at any other suitable position. Other types of speed sensors, such as pitot tubes, and processing units could be used, as would be readily recognized by one of ordinary skill in the art. Alternatively, a global positioning system (GPS) unit could be used to determine the speed of the watercraft 10 by calculating the change in position of the watercraft 10 over a period of time based on information obtained from the GPS unit.
The watercraft 10 is provided with a reverse gate (not shown) which is movable between a first stowed position where it does not interfere with the jet of water (not shown) being expelled by the jet propulsion system 84 and a plurality of positions where it redirects the jet of water being expelled by the jet propulsion system 84.
Sponsons 77 are disposed on both sides 205, 207 of the hull 200 near the transom 54. It is contemplated that the sponsons 77 could be optional. The sponsons 77 have an arcuate undersurface that gives the watercraft 10 both lift while in motion and improved turning characteristics. The sponsons 77 are fixed to the surface of the hull 200 and can be attached to the hull 200 by fasteners or molded therewith. It is contemplated that the position of the sponsons 77 with respect to the hull 200 may be adjustable to change the handling characteristics of the watercraft 10 and accommodate different riding conditions. Trim tabs, which are commonly known, may also be provided at the transom and may be controlled from the helm assembly 60.
The general construction of a jet boat 100 in accordance with this invention is shown in FIGS. 3 and 4. The following description relates to one way of manufacturing a jet boat. Obviously, those of ordinary skill in the jet boat art will recognize that there are other known ways of manufacturing and designing jet boats and that this invention would encompass these other known ways and designs.
The jet boat 100 has a hull 201 and a deck 112 supported by the hull 201. The hull 201, which is schematically shown in FIG. 3, has a width of 244 cm (8 feet) and a length of 610 cm (20 feet). It is contemplated that the hull 201 could have the width comprised between 213 and 259 cm (7 and 8.5 feet) and the length comprised between 457 and 762 cm (15 to 25) feet. However, other widths and lengths are also contemplated. The hull 201 has similar features as the hull 200 described below with respect to FIGS. 5 to 12, and as such will not be described in detail herein.
The deck 112 has a forward passenger area 122 and a rearward passenger area 124. A right console 126 and a left console 128 are disposed on either side of the deck 112 between the two passenger areas 122, 124. A passageway 130 disposed between the two consoles 126, 128 allows for communication between the two passenger areas 122, 124. A door 131 is used to selectively open and close the passageway 130. At least one engine (not shown) is located between the hull 200 and the deck 112 at the back of the boat 100. The engine powers the jet propulsion system (not shown) of the boat 100. The jet propulsion system is of similar construction as the jet propulsion system 84 of the personal watercraft 10 described above, and will therefore not be described again. A reverse gate 110 is operatively mounted to the hull 201. The reverse gate 110 is of similar construction as the reverse gate 110 of the personal watercraft 10 described above, and will therefore not be described again. In a preferred embodiment, the boat 100 has two engines and two jet propulsion systems each provided with a reverse gate 110. The engine is accessible through an engine cover 132 located behind the rearward passenger area 124. The engine cover 132 can also be used as a sundeck for a passenger of the boat 100 to sunbathe on while the boat 100 is not in operation. A reboarding platform 152 is located at the back of the deck 112 for passengers to easily reboard the boat 100 from the water.
The forward passenger area 122 has a C-shaped seating area 136 for passengers to sit on. The rearward passenger area 124 also has a C-shaped seating area 138 at the back thereof. A driver seat 140 facing the right console 126 and a passenger seat 142 facing the left console 128 are also disposed in the rearward passenger area 124. It is contemplated that the driver and passenger seats 140, 142 can swivel so that the passengers occupying these seats can socialize with passengers occupying the C-shaped seating area 138. A windshield 139 is provided at least partially on the left and right consoles 128, 126 and forwardly of the rearward passenger area 124 to shield the passengers sitting in that area from the wind when the boat 100 is in movement. The right and left consoles 126, 128 extend inwardly from their respective side of the boat 100. At least a portion of each of the right and the left consoles 126, 128 is integrally formed with the deck 112. The right console 126 has a recess 144 formed on the lower portion of the back thereof to accommodate the feet of the driver sitting in the driver seat 140 and an angled portion of the right console 126 acts as a footrest 146. A foot pedal 147 is provided on the footrest 146. The left console 128 has a similar recess (not shown) to accommodate the feet of the passenger sitting in the passenger seat 142. The right console 126 accommodates all of the elements necessary to the driver to operate the boat. These include, but are not limited to, a helm assembly in the form of a steering wheel 148, a throttle operator 76 in the form of a throttle lever, and an instrument panel. The instrument panel have various dials indicating the watercraft speed, engine speed, fuel and oil level, and engine temperature. The speed of the boat 100 is measured by a speed sensor (not shown) which can be in the form of the speed sensor described above with respect to the personal watercraft 10 or a GPS unit or any other type of speed sensor which could be used for marine applications. It is contemplated that the elements attached to the right console 126 could be different than those mentioned above. The left console 128 incorporates a storage compartment (not shown) which is accessible to the passenger sitting the passenger seat 142.
Turning now to FIGS. 5 to 12, an embodiment of the hull 200 will be described in greater detail.
The hull 200 is a double deadrise hull defined by a first portion 208, a second portion 210 disposed at respective first and second deadrise angles 220, 222. It is contemplated that the hull 200 could be a multiple deadrise hull (e.g. triple, quadruple etc.). The hull 200 is symmetrical with respect to a keel 206. The keel 206 separates the port side 205 from the starboard side 207 of the hull 200. The starboard side 207 being a minor image of the port side 205, the hull 200 will be described for the port side 205 only.
Referring more specifically to FIG. 10, the first portion 208 is located between the keel 206 and the second portion 210. The first deadrise angle 220 of about 22 degrees when measured on a cross-section of the hull 200 taken along the line 10-10 of FIG. 6. The second deadrise angle 222 of about 22 degrees when measured on the cross-section of the hull 200 taken along the line 10-10 of FIG. 6. The deadrise angles 220, 222 are measured with respect to a horizontal 250. In the embodiment shown in the Figures, the first deadrise angle 220 and the second deadrise angle 222 are identical, but it is contemplated that the first deadrise angle 220 and the second deadrise angle 222 could be different from each other. It is also contemplated that each of the deadrise angles 220, 222 could range between 12 and 25 degrees. It is also contemplated that for certain applications each of the deadrise angles 220, 222 could range between 20 and 25 degrees.
Still referring to FIG. 10, the first portion 208 has a width 266 of about 30 cm (11.8 inches) and the second portion 210 has a width 268 of about 18 cm (7.08 inches) for a total port side 205 width 272 of about 50 cm (19.7 inches). However, other widths 266 for the first portion 208 and widths 268 for the second portion 210 are also contemplated. The first portion 208 and the second portion 210 are generally continuous and flat. It is contemplated that the portions 208, 210 could have some curvature. It is also contemplated that the portions 208, 210 could be themselves interrupted or discontinuous.
Referring more specifically to FIG. 6, the first portion 208 also includes a lifting strake 240. The lifting strake 240 is located near the keel 206 at about 10 cm (3.9 inches) laterally from the keel 206. A length 265 (shown in FIG. 6) of the lifting strake 240 is about 99 cm (38.9 inches). The lifting strake 240 has a triangular cross-section, and is downwardly inclined of about 3 degrees from the waterline 212. It is contemplated that the first portion 208 could have more than one lifting strake, and that the lifting strakes could have different lengths. It is also contemplated that the second portion 210 could have one or more lifting strake. It is contemplated that the lifting strake 240 could have a different cross-sectional shape. It is contemplated that the lifting strake 240 could be inclined between 3 and 5 degrees with respect to the waterline 212.
The first portion 208 connects to the second portion 210 via a third portion 214. The third portion 214 is a small portion that acts as a transition between the first portion 208 and the second portion 210. The third portion has a width 270 of about 1 cm (0.39 inch). However, other widths 270 for the third portion 214 are also contemplated. The third portion 214 includes a first chine 230. The first chine 230 is a hard chine. It is contemplated that the first chine 230 could be a soft chine. As best seen in FIG. 12, the first chine 230 has a generally sharp edge, however it is contemplated that the first chine 230 could have a blunt edge and some radius of curvature, while still being a hard chine. The first chine 230 will be described in greater detail below. The first portion 208 forms with the third portion 214 an angle 226 of about 126 degrees when measured on the cross-section of the hull 200 taken along the line 10-10 of FIG. 6. The third portion 214 has a third deadrise angle 224 which is larger than the first and second deadrise angles 220, 222. The third deadrise angle 224 is at about 78 degrees from the horizontal 250 when measured on the cross-section of the hull 200 taken along the line 10-10 of FIG. 6. Other angles 226, 224 are also contemplated.
The second portion 210 connects to an upper portion 217 of the hull 200 at a second chine 232. The second chine 232 is a soft chine. The second chine 232 will be described in greater detail below. The second portion 210 forms with the upper portion 217 of the hull 200 an angle 228 of about 122 degrees when measured on the cross-section of the hull 200 taken along the line 10-10 of FIG. 6. The second portion 210 forms with the third portion 214 an angle 229 of about 124 degrees when measured on the cross-section of the hull 200 taken along the line 10-10 of FIG. 6. Other angles 228, 229 are also contemplated. Unlike the first portion 208, the second portion 210 does not have a lifting strike. However, it is also contemplated that the second portion 210 could have one or more lifting strakes.
The first and second chines 230, 232 extend on a majority of a length of the hull 200 from the aft 204 to a location generally toward the bow 202. The chines 230, 232 are generally parallel to the waterline 212. Because the watercraft 10 is a planning watercraft, the chines 230, 232 are downwardly inclined by about 3 degrees from the waterline 212. It is contemplated that the chines 230, 232 could be inclined between 3 and 5 degrees with respect to the waterline 212. The chines 230, 232 are uninterrupted. They are continuous and formed of a single piece. It is contemplated that the chines 230, 232 could be formed of several pieces and could be discontinuous. A length 263 of the chine 230 is about 247 cm (97.24 inches), and a length 261 of the chine 232 is about 237 cm (93.3 inches). However, other lengths for the chines 230, 232 are also contemplated. The chines 230, 232 follow a shape of the hull 200 and extend upwardly toward the bow 202. It is contemplated that only one or two of the chines 230, 232 could extend along a majority of the hull 200. It is also contemplated that the chines 230, 232 could extend along a minority of the length of the hull 200. It is also contemplated that one or more of the chines 230, 232 could extend from a location different from the aft 204.
As best seen throughout the cross-sectional views of FIGS. 7 to 11, the first chine 230 has a cross-sectional shape that changes throughout the length 264 of the hull 200. It is contemplated that the first chine 230 could have a constant cross-sectional shape throughout its length. As a radius of curvature of the first chine 230 varies along its length, the angle 226 becomes generally more acute toward the aft 204 than toward the bow 202 of the watercraft 10. Because the hull 200 is a planning hull, at high speeds, only a rear and a center portion of the hull 200 are in contact with the water. Hence the first chine 230 being a hard chine, it promotes, at high speeds, water separation which in turn reduces drag. At low speeds, however, a majority of the hull 200 is in contact with the water and the first chine 230 is submerged. Hence, at low speeds, the first chine 230 does not promote water separation but assists in maintaining a straight course when hit sideways by currents or waves. Despite the change of curvature the first chine 230 remains a hard chine throughout its length. The radius of curvature of the first chine 230 infinite when measured on the cross-section of the hull 200 taken along the line 7-7 of FIG. 6 (generally flat surface), about 38 mm (1.49 inches) when measured on the cross-section of the hull 200 taken along the line 8-8 of FIG. 6, about 43 mm (1.69 inches) when measured on the cross-section of the hull 200 taken along the line 9-9 of FIG. 6, about 22 mm (0.86 inch) when measured on the cross-section of the hull 200 taken along the line 10-10 of FIG. 6, and about 8 mm (0.31 inch) when measured on the cross-section of the hull 200 taken along the line 11-11 of FIG. 6. Other radii of curvature for the first chine 230 are also contemplated.
As best seen throughout the cross-sectional views of FIGS. 7 to 11, the second chine 232 has a cross-sectional shape that changes throughout its length. It is contemplated that the second chine 232 could have a constant cross-sectional shape throughout its length. As a radius of curvature of the second chine 232 varies along its length. The angle 228 becomes generally more acute toward the bow 202 than toward a center of the watercraft 10 to accommodate a shortening in width of the hull 200 toward the bow 202. Despite the change of curvature the second chine 232 remains a soft chine throughout its length. The radius of curvature of the second chine 232 is about 106 mm (4.17 inches) when a cross-section is taken along the line 7-7, about 141 mm (5.55 inches) when measured on the cross-section of the hull 200 taken along the line 8-8 of FIG. 6, about 138 mm (5.43 inches) when measured on the cross-section of the hull 200 taken along the line 9-9 of FIG. 6, about 123 mm (4.84 inches) when measured on the cross-section of the hull 200 taken along the line 10-10 of FIG. 6, and about 84 mm (3.3 inches) when measured on the cross-section of the hull 200 taken along the line 11-11 of FIG. 6. As can be noticed, the radius of curvature of the first chine 230, being a hard chine, it features a smaller radius of curvature than the one of the second chine 232. Other radii of curvature for the second chine 232 are also contemplated.
A reverse chine 236 is disposed on the upper portion 217 between the second chine 232 and an upper most point of the hull 200. The reverse chine 236 is disposed above the second chine 232 to allow water separation from the water that would have attached to the second chine 232, since the second chine 232 is a soft chine. As best seen in FIG. 5, the reverse chine 236 extends only on a portion of the length of the hull 200 to leave room for the sponsons 77. It is contemplated that the reverse chine 236 could be a flat chine or could be omitted.
A step 209 (shown in FIG. 5) in the vicinity of the aft 204 reduces contact of the hull 200 with the water and as a consequence reduces drag. The depressed portion 209 extends laterally along the width of the first portion 208, and extends longitudinally from the aft 204 to about the intake ramp 88. It is contemplated that the step 209 could be omitted.
Modifications and improvements to the above-described embodiments of the present invention may become apparent to those skilled in the art. The foregoing description is intended to be exemplary rather than limiting. The scope of the present invention is therefore intended to be limited solely by the scope of the appended claims.

Claims

What is claimed is:

1. A hull for a watercraft comprising:

a port side;

a starboard side; and

a keel disposed between the port side and the starboard side, each of the port and starboard sides comprising:

a first portion having a first deadrise angle;

a second portion having a second deadrise angle, the first portion being disposed laterally between the second portion and the keel;

a first chine connected to the first portion, the first portion being disposed laterally between the keel and the first chine; and

a second chine connected to the second portion, the second portion being disposed laterally between the first chine and the second chine, the second chine being a soft chine.

2. The hull of claim 1, wherein, for each of the port and starboard sides, the first chine is a hard chine.

3. The hull of claim 1, wherein the hull has a length, and wherein for each of the port and starboard sides, the first and second chines extend parallel to each other on at least a portion of the length of the hull.

4. The hull of claim 1, wherein, for each of the port and starboard sides, at least one of the first and second portions is uninterrupted.

5. The hull of claim 1, wherein, for each of the port and starboard sides, the first deadrise angle and the second deadrise angle are identical.

6. The hull of claim 1, wherein, for each of the port and starboard sides, at least one of the first and second chines is uninterrupted and extends on a majority of a length of the hull.

7. The hull of claim 1, wherein, for each of the port and starboard sides, when seen from the port and starboard sides, at least one of the first and second chines is generally parallel to a waterline of the hull.

8. The hull of claim 1, wherein, for each of the port and starboard sides, the hull further comprises a third portion and a third chine, the first chine connecting the third portion to the first portion, the third chine connecting the third portion to the second portion, the third portion having a third deadrise angle, the third deadrise angle being different from the first and second deadrise angles.

9. The hull of claim 1, wherein, for each of the port and starboard sides a reverse chine is connected to the second chine, the second chine being disposed laterally between the second portion and the reverse chine.

10. A watercraft comprising:

a hull, the hull having port and starboard sides and a keel disposed therebetween;

a deck disposed on the hull;

an engine connected to at least one of the hull and the deck;

a propulsion system operatively connected to the engine,

each of the port and starboard sides comprising:

a first portion having a first deadrise angle;

11. The watercraft of claim 10, wherein, for each of the port and starboard sides, the first chine is a hard chine.

12. The watercraft of claim 10, wherein the watercraft has a length, and wherein for each of the port and starboard sides the first and second chines extend parallel to each other on at least a portion of the length of the hull.

13. The watercraft of claim 10, wherein, for each of the port and starboard sides, at least one of the first and second portions is uninterrupted.

14. The watercraft of claim 10, wherein for each of the port and starboard sides the first deadrise angle and the second deadrise angle are identical.

15. The watercraft of claim 10, wherein, for each of the port and starboard sides, at least one of the first and second chines is uninterrupted and extends on a majority of a length of the hull.

16. The watercraft of claim 10, wherein, for each of the port and starboard sides, when seen from the port and starboard sides, at least one of the first and second chines is generally parallel to a waterline of the hull.

17. The watercraft of claim 10, wherein, for each of the port and starboard sides, the hull further comprises a third portion and a third chine, the first chine connecting the third portion to the first portion, the third chine connecting the third portion to the second portion, the third portion having a third deadrise angle, the third deadrise angle being different from the first and second deadrise angles.

18. The hull of claim 10, wherein, for each of the port and starboard sides, the hull further comprises a reverse chine connected to the second chine, the second chine being disposed laterally between the second portion and the reverse chine.

19. A hull for a watercraft comprising:

a port side;

a starboard side; and

a first portion having a first deadrise angle;

a second chine connected to the second portion, the second portion being disposed laterally between the first chine and the second chine, the first chine having a smaller radius of curvature than the second chine.