Title:
Kayak foot brace system and method
Kind Code:
A1


Abstract:
A foot brace system for use in a kayak or similar water craft. The system includes a footrest for engaging both feet of a user, and can retract and extend laterally so as to permit the system to account for variations in the beam of the craft when the footrest is moved fore or aft. The tilt angle and height of the footrest from the floor of the craft can also be adjusted. The system includes a pair of rails which are connected to the footrest via a sliding connection. The fore and aft position of the footrest is locked by a rope and cleat.



Inventors:
Chambers, Christopher Paul (Auckland, NZ)
Application Number:
11/043268
Publication Date:
08/25/2005
Filing Date:
01/27/2005
Assignee:
MYRACE LIMITED (North Shore City, NZ)
Primary Class:
International Classes:
B63H16/02; (IPC1-7): B63B17/00
View Patent Images:



Primary Examiner:
SWINEHART, EDWIN L
Attorney, Agent or Firm:
NIXON PEABODY, LLP (WASHINGTON, DC, US)
Claims:
1. A foot brace system for use in a kayak or similar water craft, the system including a footrest for engaging both feet of a user; a first connector for connecting the footrest to a first side of the craft; and a second connector for connecting the footrest to a second side of the craft; wherein the first and second connectors can retract and extend laterally so as to permit the system to account for variations in the beam of the craft when the footrest is moved fore or aft.

2. A system according to claim 1 wherein each connector includes a flexible connection member which flexes when the connector retracts or extends laterally.

3. A system according to claim 2 wherein each flexible connection member is resiliently flexible so as to provide a resilient biasing force which biases the member towards an extended position.

4. A system according to claim 1 wherein the first and second connectors are rotatably connected to the footrest.

5. A system according claim 1 wherein each connector includes a connection member and wherein the relative angle between the footrest and the connection member changes when the connector retracts or extends laterally.

6. A system according to claim 5 wherein each connector includes two or more of connection members, each connection member being rotatably mounted to the footrest, and wherein the relative angle between the connection members changes when the connector retracts or extends laterally.

7. A system according to claim 6 wherein each connector includes a resilient member mounted between a pair of connection members so as to provide a resilient biasing force which biases the connection members together.

8. A system according to claim 1 further including a first rail for mounting the first connector to the first side of the craft; and a second rail for mounting the second connector to the second side of the craft, wherein the connectors can be moved along an axis of their respective rails to move the footrest for or aft.

9. A system according to claim 8 wherein the rails have rail axes which lie in a common plane, and wherein each connector includes a connection member which extends between a first connection point adjacent to the footrest and a second connection point adjacent to a respective one of the rails, and wherein a line between the first and second connection points lies in the common plane of the rails.

10. A system according to claim 1 wherein the first and second connectors are formed as a single piece.

11. A system according to claim 1 including a stay having a lateral portion connected to the footrest and a pair of side arms extending at an angle from opposite ends of the lateral portion, wherein the side arms constitute the first and second connectors.

12. A system according to claim 1 wherein the first and second connectors each include a connection member which has an elongate cross-section.

13. A foot brace system for a kayak or similar water craft, the system including a footrest for engaging both feet of a user; a first connector for connecting the footrest to a first side of the craft; and a second connector for connecting the footrest to a second side of the craft, wherein the first and second connectors can be adjusted between a first configuration in which the footrest is oriented at a first fore/aft tilt angle; and a second configuration in which the footrest is oriented at a second fore/aft tilt angle.

14. A system according to claim 13 wherein each connector includes a pair of connection members, each connection member being rotatably mounted to the footrest, and wherein the relative angle between the pair of connection members can be adjusted to adjust the fore/aft tilt angle of the footrest.

15. A system according to claim 13 including a pair of stays each having a lateral portion connected to the footrest and a pair of side arms extending at an angle from opposite ends of the lateral portion, wherein the side arms constitute the connection members.

16. A foot brace system for a kayak or similar water craft, the system including a footrest for engaging both feet of a user; a first connector for connecting the footrest to a first side of the craft; and a second connector for connecting the footrest to a second side of the craft, wherein the first and second connectors can be adjusted between a first configuration in which the footrest is positioned at a first height with respect to the floor of the craft; and a second configuration in which the footrest is positioned at a second height with respect to the floor of the craft.

17. A system according to claim 16 wherein each connector includes a connection member and wherein the relative angle between the footrest and the connection member moves when the connector is adjusted between its first and second configurations.

18. A system according to claim 16 wherein each connector includes a pair of connection members, each connection member being rotatably mounted to the footrest, and wherein the relative angle between the pair of connection members changes when the connector is adjusted between its first and second configurations.

19. A system according to claim 18 including a pair of stays each having a lateral portion connected to the footrest and a pair of side arms extending at an angle from opposite ends of the lateral portion, wherein the side arms constitute the connection members.

20. A foot brace system for a kayak or similar water craft, the system including a footrest for engaging one or both feet of a user; a rail; a connector having a first part connected to the footrest and a second part mounted to the rail such that it can slide along the rail; and a locking device for locking the connector at a desired position along the rail.

21. A system according to claim 20 wherein the rail has an elongate rail channel running along all or part of the length of the rail, the second part of the connector being slidably mounted in the rail channel.

22. A foot brace system according to claim 20 wherein the locking device includes a first locking member which applies a shear force to a second locking member in order to lock the connector at the desired position along the rail.

23. A foot brace system according to claim 22 wherein the first locking member is a rope and the second locking member is a cleat.

24. A foot brace system for a kayak or similar water craft, the system including a footrest for engaging one or both feet of a user; and an adjuster for adjusting the fore/aft position of the footrest, wherein the adjuster includes a rope coupled to the footrest, and a cleat for locking off the rope at a desired position.

25. A foot brace system for a kayak or similar water craft, the system including a footrest for engaging both feet of a user, a pair of rails; and a pair of connectors each connecting the footrest to a respective one of the rails at a connection point positioned fore or aft of the footrest.

26. A system according to claim 25 wherein each connector includes a connection member which extends between a first connection point adjacent to the footrest and a second connection point adjacent to the respective one of the rails, and wherein a line between the first and second connection points subtends an angle with the respective rail which is less than 45 degrees.

27. A system according to claim 25 wherein the axes of the rails lie in a common plane, and wherein each connector includes a connection member which extends between a first connection point adjacent to the footrest and a second connection point adjacent to a respective one of the rails, and wherein a line between the first and second connection points lies in the common plane of the rails.

28. A system according to claim 1 further including a pair of pedals attached to the footrest.

29. A system according to claim 1 wherein the first and second connectors each include a connection member which is substantially circular in cross-section.

30. A water craft comprising: a hull; a footrest for engaging both feet of a user; a first connector for connecting the footrest to a first side of the craft; and a second connector for connecting the footrest to a second side of the craft; wherein the first and second connectors can retract and extend laterally so as to permit the system to account for variations in the beam of the craft when the footrest is moved fore or aft.

31. A craft according to claim 30 wherein the pair of connectors suspend the footrest between the first and second sides of the craft with a gap between the bottom edge of the footrest and the floor of the craft.

32. A method of locking the fore/aft position of a foot brace system in a kayak or similar water craft, the method comprising actuating a locking device while seated in a cockpit of the craft.

33. The method of claim 32 wherein the locking device includes a rope and cleat.

Description:

TECHNICAL FIELD

The present invention relates to a foot brace system for use in a kayak, canoe, or similar water craft.

BACKGROUND TO THE INVENTION

In order for a kayaker to maintain the stability of, and control over, a kayak, it is important that they are able to brace themselves in a snug, comfortable position. A footrest assists in this by enabling the kayaker to brace themselves with their feet on the footrest. Various foot brace systems have been disclosed for this purpose.

One such system employs a stationary footrest, fixed in a permanent position relative to the kayak seat (which is typically fixed). The most important limitation of this system is that it renders the kayak unsuitable for kayakers with different leg lengths. It also does not allow a kayaker to adjust the position of the footrest for comfort.

In order to overcome these problems, a variety of foot brace systems have been disclosed in which the footrest is moveable fore and aft. As the sides (gunwales) of a kayak taper inward toward the bow, if a connector is used between the footrest and the gunwales the system must accommodate variation in the beam of the kayak. A conventional solution to this problem is to attach a support for each foot to a rail on each side of the kayak and to build a taper into the rails which counteracts the taper of the hull. A problem with this solution is that the increased rail thickness introduces additional weight to the kayak and occupies a considerable part of the already limited space. It is also specific to each kayak.

The load applied to the footrest can be via the kayaker's heel or ball of their foot and these forces must be transferred to the hull via suitable connectors.

The loads applied to the footrest are:

    • induced bending moments about the connectors as the footrest is pushed forward above or below the connectors; and
    • the resultant forward load that will cause shear loading between the footrest and hull that the connectors must accommodate. This loading is likely to induce bending in the connectors.

An object of this invention is to provide an improved foot brace system, or at least to provide a useful alternative.

DISCLOSURE OF INVENTION

A first aspect of the invention provides a foot brace system for use in a kayak or similar water craft, the system including a footrest for engaging both feet of a user; a first connector for connecting the footrest to a first side of the craft; and a second connector for connecting the footrest to a second side of the craft; wherein the first and second connectors can retract and extend laterally so as to permit the system to account for variations in the beam of the craft when the footrest is moved fore or aft.

The connectors may retract and extend in a linear fashion (for instance by a telescoping action) but preferably each connector includes a connection member and the relative angle between the footrest and the connection member moves when the connector retracts or extends. This lends itself to a more simple construction.

Each connector may comprise a pair of rigid telescoping connection members. However, preferably each connector includes a flexible connection member which flexes when the connector is moved between its retracted and extended positions.

The flexible connection members are typically resiliently flexible so as to provide a resilient biasing force which biases the member towards its extended position.

The first and second connectors may be rigidly connected to the footrest. However a problem with a rigid connection is that it can result in the transmission of certain undesirable forces which are not aligned with the axis of the connectors. Therefore preferably the first and second connectors are rotatably connected to the footrest. This tends to result in forces being transmitted as tensile or compressive forces along the length of the connectors.

The fore/aft position can be achieved by simple lengthening/shortening of the connector, or by fixing the connector at a selected point along a rail.

The first and second connectors may be formed separately, or as a single piece for ease of manufacture.

In order to easily adjust the footrest fore and aft the system typically includes a first rail for mounting the first connector to the first side of the craft; and a second rail for mounting the second connector to the second side of the craft, wherein the connectors can be moved along an axis of their respective rails to move the footrest for or aft. The connectors may be movable between discrete positions along the rail, or may be continuously movable along the rail.

In on embodiment the rails have rail axes which lie in a common plane, and each connector includes a connection member which extends between a first connection point adjacent to the footrest and a second connection point adjacent to a respective one of the rails, and wherein a line between the first and second connection points lies in the common plane of the rails. This arrangement provides resistance against side to side of the footrest in the common plane (which will in most cases be approximately horizontal).

A second aspect of the invention provides a foot brace system for a kayak or similar water craft, the system including a footrest for engaging both feet of a user; a first connector for connecting the footrest to a first side of the craft; and a second connector for connecting the footrest to a second side of the craft, wherein the first and second connectors can be adjusted between a first configuration in which the footrest is oriented at a first fore/aft tilt angle; and a second configuration in which the footrest is oriented at a second fore/aft tilt angle.

In a preferred example each connector includes a pair of struts, and the tilt angle is adjusted by altering the strut locations relative to the hull. This can be achieved by altering the length of one of the struts, or altering position at which the strut is fastened to the hull. In an alternative example (not shown) the variation in tilt may be achieved by altering the connection point between the struts and the footrest.

A third aspect of the invention provides a foot brace system for a kayak or similar water craft, the system including a footrest for engaging both feet of a user; a first connector for connecting the footrest to a first side of the craft; and a second connector for connecting the footrest to a second side of the craft, wherein the first and second connectors can be adjusted between a first configuration in which the footrest is positioned at a first height with respect to the floor of the craft; and a second configuration in which the footrest is positioned at a second height with respect to the floor of the craft.

The third aspect enables the height of the footrest to be adjusted so that the foot brace system can be fitted into a variety of different kayaks and/or the height can be adjusted to suit different users.

The connectors may expand and contract in a linear fashion (for instance by a telescoping action) but preferably each connector includes a connection member and the relative angle between the footrest and the connection member moves when the connector moves between its configurations. This lends itself to a more simple construction.

Each connector may be formed by only a single connection member, but preferably each connector includes a pair of connection members, and the relative angle between the pair of connection members changes when the connector moves between its first and second configurations.

A fourth aspect of the invention provides a foot brace system for a kayak or similar water craft, the system including a footrest for engaging one or both feet of a user; a rail; a connector having a first part connected to the footrest and a second part mounted to the rail such that it can slide along the rail; and a locking device for locking the connector at a desired position along the rail.

The fourth aspect uses a slidable connection which transfers forces applied to the footrest to the locking device. The locking device can then be designed to transfer the forces in turn to the hull without risking buckling of the hull wall. In order to minimise such buckling forces, the locking device typically includes a first locking member which applies a shear force to a second locking member in order to lock the connector at the desired position along the rail. One suitable locking device is a rope/cleat device, which enables the footrest to be locked at any position.

In a preferred embodiment the rail has an elongate rail channel running along all or part of the length of the rail, the second part of the connector being slidably mounted in the rail channel. Alternatively the connector may contain a channel which receives the rail.

A fifth aspect of the invention provides a foot brace system for a kayak, the system including a footrest for engaging one or both feet of a user; and an adjuster for adjusting the fore/aft position of the footrest, wherein the adjuster includes a rope coupled to the footrest, and a cleat for locking off the rope at a desired position.

As kayak hulls are generally thin shell structures they are not well equipped to withstand buckling forces typically present in conventional systems where the hull fastening is adjacent to the footrest.

A sixth aspect of the invention provides a foot brace system for a kayak or similar water craft, the system including a footrest for engaging both feet of a user, a pair of rails; and a pair of connectors each connecting the footrest to a respective one of the rails at a connection point positioned fore or aft of the footrest.

Positioning the connection point fore or aft of the footrest tends to reduce the application of buckling forces to the hull of the craft.

Typically each connector includes a connection member which extends between a first connection point adjacent to the footrest and a second connection point adjacent to the respective one of the rails, and a line between the first and second connection points subtends an angle with the respective rail which is less than 45 degrees. The angle with the hull axis, and the side of the hull is also typically less than 45 degrees.

The following comments are applicable to all of the above aspects of the invention.

Typically the pair of connectors suspend the footrest between the first and second sides of the craft with a gap between the footrest and the floor of the kayak. This avoids stress damage when the kayak is grounded—a common event in river kayaks.

The connectors may be employ relatively broad connection members (such as a triangular sheet or plate) but preferably the connection members are relatively elongate. These elongate members may be in the form of solid struts or ropes (which can generally only transmit tensile forces) or hollow tubes (which are more rigid in compression). The cross section of the connection members may be circular, or may be elongate (which gives greater bending strength).

In the preferred examples, the connectors are adjusted by changing the point at which the connectors attach to the rail (which is in turn attached to the side of the hull). However, various other mechanisms might be used: for instance the length of the connectors may be adjusted telescopically, or the connectors may be ropes, each rope running through a fairlead which may or may not be common with another fairlead.

A strap may be employed to hold the kayaker's foot to the footrest. In this case, the connectors must be designed to accommodate loading due to pulling forces.

The connectors may fasten the footrest directly to the hull walls, or may be fitted to rails which extend fore and aft.

A seventh aspect of the invention provides a method of locking the fore/aft position of a kayak foot brace by actuating a locking device (such as a rope/cleat) while seated in a cockpit of the kayak.

DESCRIPTION OF DRAWINGS

Two examples of the invention will now be described with reference to the accompanying Figures, in which:

FIG. 1 is a cut-away view of a kayak showing a foot brace system according to a first embodiment of the invention;

FIG. 2 is an exploded perspective view of the foot brace system;

FIG. 3 is a perspective view of a stay;

FIG. 4 is a side view of the foot brace system, with the port rail and components and starboard rope removed for clarity;

FIG. 5 is a side view of the foot brace system showing height adjustment;

FIG. 6 is a side view of the foot brace system showing tilt adjustment;

FIG. 7 is a view of the foot brace system taken from the bow of the kayak;

FIG. 8 is an enlarged cut away view showing the port rail, plate and connection points;

FIG. 9 is an enlarged perspective view of the foot brace system showing the rope lead from block to cleat;

FIG. 10 is a perspective view showing part of an alternative foot brace system according to a second embodiment of the invention; and

FIG. 11 is a perspective view showing part of an alternative foot brace system according to a third embodiment of the invention.

FIG. 1 shows a foot brace system including a footrest 1-2 and adjustment mechanism 1-3 located inside a kayak hull 1-1, which defines a fore and aft hull axis (not labelled).

FIG. 2 shows an exploded view of the complete arrangement. The footrest includes a simple flat plate (6) that is shaped to allow the kayaker's foot to be well supported from the heel to the ball of the foot. The plate height is 190 mm with a width of 260 mm that could differ in set steps such as 310 mm, 360 mm or others (possible as low as 200 mm) depending upon kayak beam. The height can also vary to accommodate foot size and typically could be as small as 150 mm. The lower edge of the plate (6) is shaped to provide a close fit with the kayak floor without contact. The plate (6) supports two pedals that are made from a forward and aft half (8),(9) for the starboard pedal and (10),(11) for the port pedal. These share a common pivot (7) that allows each pedal to rotate independently of the other and by use of cord or wire (not shown) attached to the top of the pedals the pedals can control a rudder (not shown) mounted at the kayak transom.

Rails (1) and (2) are formed from extruded Aluminium and fastened to the inside of the kayak hull (using nuts and bolts or adhesive) near to the gunwale line parallel with the kayak floor. The rails comprise a cylindrical channel. The channel is semi-enclosed with a slot running the length of the channel facing toward the centre of the kayak.

The plate (6) is supported by three stays (3), (4) and (5) formed from drawn stainless steel. These stays provide the connection between the footrest and the hull. Each stay is connected to the rails (1) and (2) via pairs of sliding blocks (15), (16) and (17). The sliding blocks (15), (16) and (17) are cylindrical and fit into the cylindrical channel in the rails (1) and (2). The attachment of the stays (3), (4) and (5) to the sliding blocks is made possible through the slot in the rail which provides an opening from the channel to the interior of the kayak. The relative diameters of the cylindrical channel in the rails and the sliding blocks are such that the sliding blocks can freely move along the length of the channel. The size of the slot in the rails relative to the diameter of the sliding blocks is such that the sliding blocks are held securely in the channel and are not able to move through the slot.

The stays connect to the sliding blocks by extending through the slot in the rails. The stays are fastened into the sliding blocks by means of a thread. There are threaded holes in the sliding blocks to receive the ends of the stays, and the ends of each stay are threaded.

Each stay has a lateral portion 3-3, two stay legs 3-2 at an angle to the lateral portion 3-3, and two end legs 3-1 approximately parallel with the lateral portion 3-3. The stays (3), (4) and (5) are flexible, so that the angle between the stay legs 3-2 and the lateral portion can vary. This enables the stays to retract and extend laterally so as to adjust to the variable widths that occurs between the rails (1) and (2) as the rails converge towards the bow.

As shown most clearly in FIGS. 2,4 and 6, the stay (5) is clamped against the forward side of the plate (6) near its upper edge by a pair of upper clamping washers (12). The stay (5) is received in a relatively narrow channel (not labelled) in the upper clamping washers (12). Similarly, the stays (3,) (4) are clamped against the forward side of the plate (6) near its bottom edge by a pair of lower clamping washers (13). The stays (3) (4) lie together in a relatively wide channel (not labelled) in the lower clamping washers (13), which is wide enough to accommodate both stays.

The lateral portions 3-3 of stays (3) and (4) are in contact and can be considered to be one axis. As shown in the side views of FIGS. 3 to 6, three corner nodes of a triangle are defined by the axis formed by the lateral portions 3-3 of stays (3) and (4), and the end legs 3-1 of the same stays where they attach to the sliding blocks (15)(16). This triangle has two fixed sides (the two stay legs 3-2) and one variable side (the distance between the sliding blocks (15) and (16)). By controlling the distance between the two blocks the distance of the lateral stay portions 3-3 running across the plate to the kayak floor can be controlled. Thus the distance between the blocks can be adjusted to set the height of the plate from the kayak floor.

The distance between the sliding blocks (15) and (16) is controlled by a height adjustment tie rod (19). One end of the rod (19) is fastened into the forward slide block (15) by a thread identical to those used to connect the stays to the sliding blocks. The other end is not threaded and lies inside a clearance hole in sliding block (16). The distance between the sliding blocks (15) and (16) can be altered by moving the non threaded end of the rod (19) out of one of the holes (as shown in 4-1 FIG. 4) in the slide block and then allowing it to fit into another hole (as shown in 5-1 FIG. 5) as required and thereby altering and securing the distance between the sliding blocks (15) (16) and therefore the height of the plate from the kayak floor.

The fore/aft inclination of the plate (6) from the vertical can also be adjusted by adjusting the position on the aft sliding block (17) to which stay (5) is connected (Stay (5), as follows. The stay (5) is threaded into aft sliding Block (17) into a selected one of a row of threaded holes in the aft sliding block. In order to adjust the fore/aft inclination, the stay (5) is first removed from aft sliding block (17) by sliding the block out of the rail in which it is held (1) or (2). The aft sliding block is then unthreaded from the stay, and rethreaded onto the desired hole. The aft sliding block is then inserted back into the rail.

Once adjusted for height clearance from the kayak floor and tilt as desired, the footrest can be positioned and anchored at a position best suited for the intended kayaker. The sliding blocks are all free to move fore and aft in the rails. Forward movement of the sliding blocks is fixed by a position adjust rope (23) that is held by a rope cleat (18). One method to find the correct position for the plate is to pull on the position adjust rope (23) on both sides and locate the footrest as far aft as possible while still retaining the sliding blocks in the rails. With the position adjust rope (23) removed from the cleats (18) the kayaker can then enter the kayak and push the footrest forward with their feet stopping at the position that suits their seating and leg extension preference. It is then possible for the kayaker to fix the position adjust rope (23) into the respective cleats on each side while still seated in the kayak; or if preferred, to exit the kayak and then set the rope into the cleat on both sides. This sets the footrest positioning fore and aft.

FIG. 9 shows the position adjust rope (23) which leads from a simple knot through the rope/stop slide (22) 9-1 forward 9-2, 9-3 and through a clearance hole in middle sliding block (16) 9-4 then through the slot 9-5 in the respective rail back to the rope cleat (18) 9-7. When forward force is applied to the plate (6) and the complete supporting assembly slides in the rails, the looped rope ensures that rope stop/slide (22) and middle sliding block (16) are pulled together trapping sliding block (aft) (17). This ensures that sliding block (aft) (17) is unable to slide aft if force is applied to the footrest below the lateral axis of stay (3) or (4) which would cause the lower portion of the plate to move forward and the upper portion to move aft.

As kayak hulls are generally thin shell structures they are not well equipped to withstand buckling forces typically present in other systems where the hull fastening is adjacent to the footrest. Ideally the force would be in complete shear across the surface of the hull. In this invention the forces applied to the plate by the kayaker's foot are transferred to the hull via the stays. This method of transfer provides an advantageous loading case on the hull as the flexible or hinged nature of the stay connections to the plate and slide blocks ensure the stay is in tension. The connections are not capable of transferring any significant load other than in the axis of the stay due to their flexible or hinged nature. With the stay axis set at an acute angle to the hull surface the major force is in shear with the hull. The force component normal to the hull surface is transferred via the rail.

FIG. 10 shows a partial view of an alternative foot brace system according to a third embodiment of the invention. In this case each side of the footrest is connected to a rail by a single broad flexible connector.

FIG. 11 is a perspective view showing part of an alternative foot brace system according to a third embodiment of the invention. The starboard half of the system is shown, and the port side is a mirror image. A rail 30 is mounted to the side of the kayak (not shown). The rail is C-shaped in section to provide a slot running along its length which slidably receives bars 31 and 32. The bars 31 and 32 have lugs 35, 36 which support opposite ends of a coil spring 36. The spring 36 is in tension, biassing the bars together. Stay 33 is connected to the bar 31 and stay 34 is connected to the bar 32, via respective hinges. The stays 33, 34 are connected together at their other ends by a third hinge (not labelled). A footrest mount 38 is connected in turn to the stays 33, 34, at a fourth hinge 41 adjacent to the hinge connecting the stays 33, 34. The footrest mount 38 may be attached rigidly to the footrest 39, or may be attached by a pivoted connection with the pivot perpendicular to the side face of the plate 38. A stay 40 is connected between the lower part of the footrest 39 and the stay 34 to resist fore/aft tilt. A pivoted connection between the footrest 39 and footrest mount 38 would allow for fore/aft tilt adjustment by altering the effective length of the stay 40.

In contrast with the system of FIG. 1, the system of FIG. 2 is only adjustable fore and aft, and cannot be adjusted vertically.

The action of spring 37 tends to bias the hinge 41 towards the rail. When acting together with the spring (not shown) on the port side of the kayak this tends to move the footrest forward due to the steadily narrowing beam. This forward bias may be overcome by frictional forces between the bars 31, 32 and the rail 30, but the footrest is also prevented moving forward by a suitable locking device such as a rope (not shown) attached to stay 34 or bar 32 and made fast by a cleat (not shown) on the rail 30.

When the footrest is locked in this manner, the spring action resists movement of the hinge 41 side-to-side, as explained below. For the footrest to move sideways a sideways force has to make hinge 41 move. For this to happen, stay 33 has to apply a force along the rail axis to the bar 31. This can only be done as a component of the force acting along the stay 33. Due to the angle between stay 33 and a line normal to the rail 30 being acute, the transverse force acting to push or pull the bar 31 against the rail will be greater than the axial force acting to push or pull the bar 31 along the rail. Also, on one side of the kayak the bar 31 will need to be moved opposite to the spring force, adding further to the resistance. Due to the acute angle of stay 33, any sideways force it at a mechanical disadvantage to these resisting forces.

The stiffness of the connector between the footrest and the rail is also greater than the embodiment of FIG. 1 because the stays 33, 34 extend horizontally. Contrast this with the stays in FIG. 1 which extend at an angle to the horizontal. More generally, the rails have rail axes which lie in a common plane (which is typically horizontal although it may be at a slight angle to the horizontal), and a line between footrest mount 38 and each hinge connecting the stays 33, 34 to bars 31, 32 lies in that common plane.

When the footplate is to be moved aft, force can be applied to the stay 34 or bar 32 (by pulling on the rope). This force will have a major component along the axis of the rail and therefore will not face much resistance. Due to the difference in stiffness between the stay 34 and spring 37 this force will tend to move the hinge 41 inboard thus expanding the linkage to account for the increase in beam as the footrest is moved aft.

The arrangement provides a resisting force (thanks to friction and the spring and the mechanical disadvantage through the linkage) to sideways movement that is higher than the typical load in this direction and therefore ‘holds’ it in place ‘locked’ but in contrast the force resisting the movement along the rail is lower than the typical force expected to make this adjustment. Therefore the adjustment fore and aft can be made without the need to release a clamp or lock mechanism for sideways movement yet still provide an effective ‘lock’ to sideways movement at any position along the rail.

In contrast to the circular cross-section stays in FIG. 1, the stays 33, 34 are elongate in cross-section (in this case, rectangular). This gives strength in bending and since the stays are supported by a cantilevered means at the rail end they will provide vertical support for the footplate.

In an alternative further embodiment (not shown), the coil spring 37 may be omitted. In this case, the bar 31 has a groove which slidably receives an end of the bar 32. After the linkage has been adjusted to its desired position, the bar 32 can be locked in the groove by a wing-nut.

While the present invention has been illustrated by the description of the embodiments thereof, and while the embodiments have been described in detail, it is not the intention of the Applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, representative apparatus and method, and illustrative examples shown and described. Accordingly, departures may be made from such details without departure from the spirit or scope of the Applicant's general inventive concept.





 
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