US20150307168A1

US20150307168A1 - Kayak stabilizer

Info

Publication number: US20150307168A1
Application number: US14/468,726
Authority: US
Inventors: Wayne PLIMMER
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-04-23
Filing date: 2014-08-26
Publication date: 2015-10-29
Also published as: CA2849610A1

Abstract

A stabilizing ballast system for a kayak. A movable ballast weight is configured to be deployed below the kayak for maximal stability, and raised above the bottom of the hull in order to navigate in shallow water or when beaching the kayak. The ballast weight system is user-configurable over a wide range of weights.

Description

FIELD OF THE INVENTION

This invention is in the field of accessories for watercraft, in particular systems that improve watercraft stability.

BACKGROUND

Watercraft such as kayaks and canoes are popular recreational items. While they are both highly maneuverable and efficient, they along with other similar types of craft suffer from a limitation common to all watercraft, that being lateral instability. Since the center of gravity of any watercraft is typically above the waterline when the boat is in the water, tipping of the boat from side to side as can occur through movement of the occupants or the load, or from the action of waves hitting the boat from the side, can result in tipping and in some cases capsizing of the boat.
It has been common in many types of boat designs, for example sailboats to provide heavily weighted keels in order to improve lateral stability and prevent capsizing. However, a problem with fixed keels is that in order to be effective they must extend well below the waterline, and in most cases are not movable. While this may not be an issue for boats that are operated in waters of sufficient depth, there nonetheless remains that the keel will run aground making the boat inoperable and potentially damaging or destroying the boat.
In some cases, attempts have been made to provide movable ballast systems that are suspended from the bottom of a watercraft. Such systems have been known for at least 100 years. For example, U.S. Pat. No. 1,082,133 (Olechnowicz) discloses a movable suspended ballast system. The system can be raised closer to the underside of the hull in order to reduce the clearance needed for the boat when navigating in shallower waters.
Similarly, U.S. Pat. No. 6,382,121 (Yu) discloses a boat ballast system that provide a weight suspended from underneath a sailboat. The weight is further movable to decrease the draught of the vessel in shallow water.
However, a limitation of both designs is that the ballast weight is always submerged and cannot be raised above the waterline. Such a solution is limiting for use in craft such as kayaks and canoes which are frequently beached from time to time, rather than moored in a harbor environment. Thus, these prior art ballast systems would continually be at risk of fouling or damage if it were to be used on a kayak or similar craft.

SUMMARY OF THE INVENTION

The present application discloses a novel apparatus and methods for improving stability of watercraft, in particular kayaks, canoe and similar styles of craft. It is well known that kayaks and canoes are comparatively unstable on account of having a fairly narrow beam, combined with the center of gravity of passengers and equipment being well above the waterline. This is particularly true in kayaks where stability is traded for speed and maneuverability.
The system described herein comprises a movable weight system that can be attached to a kayak or like craft, and which is movable over a range of positions. The weight is attached to two struts, each strut being attached to one side of the boat via an articulating joint. At one extreme, the weight can be suspended directly below the boat such that it is effective to lower the overall center of gravity of the boat. At the opposite extreme, the weight can be raised, and if the struts are of sufficient length, to a position above the water line.
The present apparatus thus provides an improved watercraft stabilizer that can provide significant stability to a craft such as a kayak, and is able to be moved out of the way when the craft is in shallow water or where objects under the waterline might catch on or otherwise damage the suspended weight or supporting struts.

BRIEF DESCRIPTION OF THE DRAWINGS

While the invention is claimed in the concluding portions hereof, preferred embodiments are provided in the accompanying detailed description which may be best understood in conjunction with the accompanying diagrams where like parts in each of the several diagrams are labeled with like numerals, and where:

FIG. 1 depicts a perspective view of one embodiment of the stabilizer system in the lowered (upper panel) configuration;

FIG. 2 depicts the stabilizer system embodiment of FIG. 1 in the raised (lower panel) configuration;

FIG. 3 depicts a front view of an embodiment of the stabilizer system in the lowered (upper panel) configuration;

FIG. 4 depicts a front view of the embodiment of FIG. 3 in the raised (lower panel) configuration;

FIG. 5 depicts a side view of the embodiment of the stabilizer system of FIG. 3 in the lowered (upper panel) configuration;

FIG. 6 depicts a side view of the embodiment of the stabilizer system of FIG. 3 in the raised (lower panel) configuration; and

FIG. 7 depicts a front view of the stabilizer system showing the operation of the system to counteract a destabilizing force when the watercraft is in use.

DETAILED DESCRIPTION OF THE INVENTION

The present disclosure describes a stabilizing system for use with watercraft, for example, but not limited to, watercraft such as kayaks and canoes. As is well-known in the art, these types of craft are inherently laterally unstable on account of the center of gravity of the boat in combination with occupants and load typically being above the waterline. As a result forces applied laterally to the boat and its load can easily result in the boat capsizing. This is especially true when boating conditions include significant wave action and/or wind.
As shown in FIG. 1, the system comprises a ballast weight 100, suspended from a pair of struts 110, one strut being attached to each side of the boat 10. Each strut 110 attaches to the boat via an articulating joint 120. The joint permits each strut to be pivoted independently through at least 180° degrees of movement or more. The ballast weight can be connected to each strut via a pivotable joint 101, such that the body of the weight can pivot relative to each strut. Providing a pivotal connection between the weight and each strut allows the stabilizer weight to maintain the most efficient hydrodynamic positioning with respect to the relative current flow of water with respect to the boat even as the weight is raised or lowered with respect to the waterline. FIG. 1 shows the system in the lowered configuration, and FIG. 2 demonstrates the embodiment of FIG. 1 in the raised position.
In some embodiments, the ballast weight holder will comprise a substantially hollow body portion, which will generally be shaped so as to result in minimal drag when deployed in the water. For example, in some cases the body can be shaped similar to a torpedo, with tapered front and rear portions so as to provide a streamlined profile. The body can be fashioned from any number of resilient materials such as metals or plastics, without limiting the scope of the invention. Providing a hollow body allows the ballast weight holder to be filled with varying amounts of material in order to provide a desired weight. For example the body of the ballast weight holder could be completely filled with a ballast material to provide maximal stabilizing effect, or partially filled where less stabilizing effect was desired.
The ability to vary the actual weight of the ballast weight provides users with different skill levels, differing degrees of added stability when using the system. As such, a beginner in the particular watercraft could use a relatively heavier ballast weight in order to provide maximal lateral stability and greater safety in operation of the boat. In contrast, a more experienced user might prefer less weight, trading stability for increased speed and agility of the boat. Providing a substantially hollow and fillable body portion for the ballast weight holder permits users to readily vary the amount of weight used.
In some cases it will be convenient to provide users with pre-measured amounts of ballast material (for example lead shot or other dense material) so that a user can quickly add a known amount of weight to the ballast weight holder. Thus, it will be convenient to provide users with pre-measured weights in amount such as 1, 2, 5, 10, 15, 20 or more pounds in pre-measured packages for easy loading into the hollow interior of the ballast weight holder.
In an alternative embodiment, the ballast weight holder rather than being fillable could be provided as a kit of pre-filled holders that cover a range of desired weights. For example, such a kits could include a plurality of holders already loaded with a specific weight, for example 1, 2, 5 10, 15, 20 or more pounds per holder. Accordingly, a user could simply select a ballast weight holder of the desired weight, and attach that holder to the struts of the system, without the need to make any measurements of ballast material, or risk the loss of ballast material by spillage during the filling or removal of ballast from a fillable ballast holder.
Similarly, in some embodiments, the ballast weight might be a solid object that is not fillable, but instead has a set weight. In this case, the user could be provided with a system having a number of ballast weights of varying size from which the user could select one or more to attach to the supporting struts of the system. In some cases it might be preferable to provide set weight that can be reversibly connected to each other, for example snap together weights, so that a number of smaller weights could be connected together either in series or in parallel to provide a heavier overall ballast to the boat.
Thus, a user could be provided with a set of weights that could be connected in various combinations to produce the desired amount of ballast. Such a kit might include a 1, 2, 3, 5, 10 and 20 pound weight. By combining different weights, ballast could be increased in increments of 1 pound through a range from 1 pound to 41 pounds. For example if one desired 17 pounds of ballast in the system, they could connect one each of a 10, 5 and 2 pound weight to produce the desired 17 pounds. Those of skill in the art will now appreciate that using the described combinations virtually any amount of ballast could be configured by combining weights. It will also be appreciated that the maximum illustrated example of 41 pounds is only an example and not specifically limiting to the maximum amount of weight that might be included in the ballast system when in use.
It will be understood that the exemplary weights provided above are simply illustrative of possible amounts of weight that can be contained with the ballast holder of the present and not limiting in terms of the precise amount of weight that one may wish to have in any particular ballast holder installed in the overall system.
As also shown in the Figures, the ballast weight will preferably be attached to two struts, each of the struts in turn attached to either side 50 of the boat. As mentioned, each strut is attached to the boat via a pivotable joint, for example a ball and socket joint, that allows the strut to be rotated through a wide range of arc. In some embodiments, the struts could be mounted to the boat on a rotatable mount such as a post 121 that extends outwardly from the side of the boat, with the strut mounted on the post via a bushing that freely rotates on the post. Regardless of the type of joint used, the joint will generally be designed to permit relatively free motion of each strut with respect to the boat. A post will also be useful regardless of the specific type of joint in order to provide clearance between the strut and the side of the boat.
In order to raise and lower the ballast weight, the system further conveniently includes a deployment member 130, for example a line or rope that can be attached to the system at point near where the ballast weight is attached to the struts. The precise location of the line is not critical to the operation of the system, but those of skill in the art will recognize that in terms of applying even force to raise or lower the ballast weight, the most efficient point of connection will be approximately where the ballast weight connects to the struts. The line can be designed to extend over an end of the boat (either the bow or stern), and preferably pass over a pulley 140 or through similar conduit, along the top deck and will be long enough to be reachable by a user when seated in the boat.
The system can further include a locking mechanism 150, such as a cleat or other similar device to secure the line and maintain the ballast weight in a desired location. In some cases the line can be pulled or released manually to raise or lower the weight. In other cases it may be desirable to raise or lower the ballast weight by use of a motorized system such as a lightweight winch that can be activated to reel in or play out the line in order to raise or lower the ballast weight. It may also be desirable to provide one or more calibration markings 160 along the line to indicate the position of the ballast weight relative to the bottom of the boat since most of the time the ballast weight will not be visible to an occupant of the boat. For example, the line could include some form of indicator marking to indicate how far the weight is above or below the waterline.
The marking could be calibrated so as to be readable with respect to a fixed point on the top deck of the boat, or with reference to the pulley or conduit through which the line passes or some other fixed point of reference. For example a reference mark could be placed on the top deck and the line comprised of two different colors, such as red and green. If the color of the line at the reference mark is red, it would indicate the ballast weight is below the water line, while of the color of the line at the reference mark was green, it would indicated that the ballast weight was above the water line of the boat. Calibrating the line in such a way would reduce the risk of inadvertently having the ballast weight deployed when in shallow water or when near underwater objects that could snag or otherwise cause damage to the ballast weight or the supporting struts.
FIG. 3 depicts a view of the system from the front of a boat 10 in the raised (top panel) position, and FIG. 4 shows the system in the lowered (bottom panel) position. As can be seen, the struts 110 can be mounted such that the struts will substantially clear the sides of the boat, to prevent abrasion of the surface finish when the struts are moved to raise or lower the ballast weight. As can be seen from this frontal view, a torpedo shaped ballast weight 100 presents a streamlined profile with respect to the direction of travel of the boat relative to the water. FIGS. 3 and 4 also show that the struts can be attached to the sides of the boat via articulating joints 120, for example a ball and socket joint. As described above, it is also possible to mount the struts with a post 121 and bushing combination that will allow similar freedom of movement of each strut relative to the boat.
As also depicted, the struts (or rods) can be fashioned of any number of resilient materials that are generally rigid. For example, the struts could be produced from metals such as aluminum, or from carbon fiber rods, which have the advantage of being strong yet very lightweight. It will be understood that the precise nature of the material use to fashion the struts will not be limiting to the scope of the invention.
FIG. 3 illustrates that in one case, it will be desirable to deploy the ballast weight so that it is positioned substantially directly underneath the position of the boater, more or less in line with the center of gravity of the loaded boat. This positioning will provide the maximal lowering of the center of gravity of the loaded boat and hence maximal stabilizing effect. FIG. 3 further represents that a line can be used to raise the ballast weight to a position where the ballast weight is substantially above the bottom surface of the boat, thus protecting the weight from snagging or being damaged when navigating in shallow water, or when it is desired to beach the boat.
FIGS. 5 and 6 depict the ballast weight system from a side view, in either the raised or lowers position. As can be seen, the ballast weight 100 can comprise a streamlined torpedo shape, suspended from struts 110 attached to the side of the boat 10. Because of the angle of the figure, the strut in the foreground covers the one on the opposite side of the boat. As indicated there are two struts, one on the port side the other on the starboard side of the boat. Thus, this figure should not be interpreted to mean that there is a single strut connected to the ballast weight. As can also be seen, in some embodiments it may be preferable to mount the struts roughly at the midpoint of the boat, since that is typical close to the center of gravity. Mounting at the midpoint will therefore provide maximal lateral stability when the ballast weight is deployed underneath the boat as is shown in the top panel. FIG. 5 further shows in the bottom panel the ballast weight in the raised position, such that the weight is substantially above the bottom surface of the boat as would be desired in shallow water, or when preparing to beach the boat after an outing.
FIG. 7 provides a depiction of the mode of operation of the invention. As will be familiar to those who have used kayaks and other similar watercraft, these types of watercraft are inherently unstable as the center of gravity is typically above the water line. In addition, boats such as kayaks and canoes typically do not have any substantial keel structure, which might otherwise contribute in part to improving lateral stability. Ironically, this is not a flaw in the design of boats and kayaks but rather an intended approach to provide a boat that is maneuverable and relatively efficient in moving through the water.
As shown in FIG. 7, any perturbation due to movement of the occupant 200, or shifting of a load can result in a lateral moment 300, with a force vector acting about an axis defined by the center of gravity 330 and hence above the waterline 400. This lateral moment is well-known as the tendency of a kayak or canoe to tip when a change in the position of a load and in particular occupants occurs. The force vector of the lateral moment 300 will result in the lateral rotation of the boat and its occupants and load with the axis of rotation positioned at the center of gravity. If the force vector is sufficiently large, the boat will rotate laterally around the center of gravity to the point where the gunwales 30 are below the waterline 400, which will typically result in capsizing of the boat. Capsizing can be exceedingly dangerous depending on the skill of the user and/or the conditions in which the boat is being used. Moreover, the tendency of the boat to be laterally unstable will increase the higher the center of gravity.
By providing a ballast weight suspended below the boat hull, the present system operates to lower the center of gravity of the boat and load, which improves lateral stability. Thus, when the ballast weight is deployed below the boat the center of gravity is lowered (indicated by reference numeral 331) and a substantially greater lateral force moment will be required in order to tip the boat to the point of capsizing. Similarly, the ballast weight will operate to neutralize lateral instability as gravity produces a force vector 310 that acts on the ballast weight. In addition, hydrodynamic drag 320 acting on the ballast weight 100 will tend to counteract the tendency of the boat to tip laterally, further contributing to the stabilizing effect of the present system.
As can be appreciated, when the boat is perfectly stable the ballast weight will be aligned with the gravitational force vector acting through the boat and ballast apparatus. When the boat is laterally de-stabilized, as depicted in FIG. 7, the ballast weight will no longer be aligned with the gravitational force vector acting through the boat and ballast system but will be laterally offset due to tipping of the boat. The force of gravity acting through the ballast weight will create a resultant force vector that will result in a moment that will tend to move the ballast weight towards a position aligned with the force of gravity acting through the boat's center of gravity, which results in the tendency to return the boat to a more upright orientation.
The magnitude of the force vector 310 will depend in turn on the amount of weight in the ballast weight. Thus, gravity acting on a heavier ballast weight will create a greater stabilizing force than would be observed when using a lighter ballast weight. Thus, by providing the ability to vary the mass of the ballast weight, the present system is able to be “fine-tuned” to provide a desired degree of stability. Accordingly, beginning kayakers (or whatever watercraft one wishes to install the system on) might select a heavier weight in order to provide more stability, while a more experienced kayaker might select a lighter weight to improve overall performance of the boat. Similarly, even experience kayakers might choose heavier ballast weights when operating in conditions that would be expected to challenge even a skilled kayaker, for example, in conditions of high wind and/or wave action.
Finally, as has been discussed the ballast weight system is designed such that when in shallow water, or when beaching the boat, the user can raise the weight by pulling on the line, thus pulling the weight upwards as the struts pivot in their respective joints. In some cases it can be desirable to provide a winch mechanism in order to operate the line. Such a winch could be manually driven or motor-driven. The system can further include a locking mechanism to secure the line in place when the ballast weigh is in the desired position relative to the hull.
In addition, it will be apparent to those of skill in the art that by routine modification the present invention can be optimized for use in a wide range of conditions and application. It will also be obvious to those of skill in the art that there are various ways and designs with which to produce the apparatus and methods of the present invention. The illustrated embodiments are therefore not intended to limit the scope of the invention, but to provide examples of the apparatus and method to enable those of skill in the art to appreciate the inventive concept.
Those skilled in the art will recognize that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the scope of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced.

Claims

1. A watercraft stabilizing system for use in combination with a watercraft, comprising:

a first strut and a second strut;

wherein the first strut is reversibly secured to a position on one side of the watercraft by a first articulating joint;

wherein the second strut is reversibly secured to the watercraft at a position substantially opposite the first strut, by a second articulating joint;

at least one ballast weight;

wherein the at least one ballast weight is suspended from the first and second struts;

a deployment member;

wherein the deployment member is attached to at least one of the first strut, the second strut or the ballast weight;

wherein the deployment member is configured to move the at least one ballast weight between a first position and a second position; and

wherein the watercraft comprises a hull, and wherein in the first position the ballast weight is positioned substantially below the bottom of the hull, and wherein in the second position the ballast weight is positioned substantially above the bottom of the hull.

2. The system of claim 1 wherein the ballast weight further comprises a hollow body portion, wherein the hollow body portion comprises a filler port through which ballast material is admitted to the interior of the body portion, and a cap configured to engage the filler port such that ballast material contained within the interior of the body portion is prevented from exiting through the filler port.

3. The system of claim 1, wherein the deployment member comprises a user-operable line configured such that the user can operate the line to move the at least one ballast weight between the first position and second position.

4. The system of claim 1, wherein the at least one ballast weight comprises a plurality of ballast weight elements.

5. The system of claim 1, wherein the at least one ballast weight comprises a weight in a range from about 1 pound to about 40 pounds.

6. The system of claim 4, wherein the plurality of ballast weights can be configured to provide ballast in a weight ranging from about 1 pound to about 40 pounds in increments of 1 pound.

7. The system of claim 3, further comprising a pulley positioned between the user and the at least one ballast weight, and through which the user-operated line passes.

8. The system of claim 1, further comprising a locking member, configured to maintain the deployment member in a substantially fixed position.

9. The system of claim 1, further comprising a winch, wherein the winch is configured to take up or release the deployment at the command of the user.

10. The system of claim 9, wherein the winch comprises one of a manual winch or a motorized winch.

11. A method of stabilizing a watercraft, the method comprising:

providing a stabilizing system, the stabilizing system comprising:

a first strut and a second strut;

at least one ballast weight;

a deployment member;

wherein the deployment member is configured to move the at least one ballast weight between a first position and a second position;

wherein the watercraft comprises a hull, and wherein in the first position the ballast weight is positioned substantially below the bottom of the hull, and wherein in the second position the ballast weight is positioned substantially above the bottom of the hull;

installing the stabilizing system on a watercraft; and

moving the at least one ballast weight between the first position and second position in order to modify the stability of the watercraft.

12. The method of claim 1, wherein the at least one ballast weight comprises a hollow body portion, wherein the hollow body portion comprises a filler port through which ballast material is admitted to the interior of the body portion, and a cap configured to engage the filler port such that ballast material contained within the interior of the body portion is prevented from exiting through the filler port.

13. The method of claim 1, wherein the deployment member comprises a user-operable line configured such that the user can operate the line to move the at least one ballast weight between the first position and second position.

14. The method of claim 1, wherein the at least one ballast weight comprises a plurality of ballast weight elements.

15. The method of claim 1, wherein the at least one ballast weight comprises a weight in a range from about 1 pound to about 40 pounds.

16. The method of claim 14, wherein the plurality of ballast weights can be configured to provide ballast in a weight ranging from about 1 pound to about 40 pounds in increments of 1 pound.

17. The method of claim 13, further comprising providing a pulley positioned between the user and the at least one ballast weight, and through which the user-operated line passes.

18. The method of claim 11, further comprising providing a locking member, configured to maintain the deployment member in a substantially fixed position.

19. The method of claim 11, further comprising providing a winch, wherein the winch is configured to take up or release the deployment at the command of the user.

20. The method of claim 19, wherein the winch comprises one of a manual winch or a motorized winch.