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Patent Searching and Data


Title:
SAILBOAT HIKING STICK ASSEMBLY
Document Type and Number:
WIPO Patent Application WO/1991/017082
Kind Code:
A1
Abstract:
A sailboat hiking tiller stick assembly having a base (41a, 41b) attached to a boat tiller carrying a vertically disposed fixed shaft (36) that mounts a vertically rotatable saddle (30) compressed between a pair of compression surfaces about the shaft which has vertical arms that compressively mate with those of another similar saddle (24), the two saddles positioned on a horizontal axle (45) providing an axis of rotation, the axes of rotation of the saddles positioned adjacent to one another. A hiking stick extension member (21) is attached to the center span of the saddle (24) that is not mounted on the fixed shaft.

Inventors:
DAVENPORT FRANK A (US)
Application Number:
PCT/US1990/002486
Publication Date:
November 14, 1991
Filing Date:
May 04, 1990
Export Citation:
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Assignee:
STAFAST PRODUCTS INC (US)
International Classes:
B63H25/08; (IPC1-7): B63H25/06
Foreign References:
US4262619A1981-04-21
US4639147A1987-01-27
US4656960A1987-04-14
US4553496A1985-11-19
Download PDF:
Claims:
THE INVENTION CLAIMED IS:
1. A sailboat hiking stick tiller extension assembly comprising: a base mounted on the tiller having a vertically disposed upstanding fixed shaft carrying an annular shoulder at an upper end and a compression adjusting member at a lower end; a first saddle having a pair of spaced apart upstanding arms separated by a center span, pivotally mounted on the annular shoulder of the shaft through the center span, said shaft defining a vertical axis of rotation; a pair of compression surfaces mounted on the shaft and frictionally confining the center span of the first saddle; a second saddle having a pair of spaced apart upstanding arms separated by a center span, the arms mating with the arms of the first saddle and pivotally attached thereto; a horizontally oriented axle having opposing ends, fixed at one end to an arm of a saddle, and extending through the mated arms of the saddles to define a horizontal axis of rotation, and having a compression adjusting member at its other end; a second pair of compression surfaces mounted on said axle and frictionally separating the mated arms of the saddles; a spacer member horizontally disposed over the axle between the center spans of the saddles and adapted to maintain spacing integrity of the saddle arms under converging compressive force; a hiking stick extension member perpendicularly extending from the center span of the second saddle; and the pivot points of each of said saddles being substantially adjacent to one another.
2. The assembly of claim 1 wherein the shaft is noncircular over a lower end portion.
3. The assembly of claim 1 wherein the compression surfaces are washers.
4. The assembly of claim 1 wherein the compression surfaces are integral with the saddles.
Description:
SAILBOAT HIKING STICK ASSEMBLY

BACKGROUND OF THE INVENTION

This invention relates to a sailboat hiking stick or tiller extension assembly which is smoothly and uniformly moveable in all orientations while maintaining a fixed position upon attaining any orientation.

Smaller sailboats are usually steered by a tiller directly connected to a rudder or to a pivot shaft upon which the rudder is mounted. To facilitate steering, especially under high performance conditions such as racing or heavy weather, a tiller extension or hiking stick is commonly attached to an end portion of the tiller to form an extension of the tiller from the boat's center line to the helmsman at the boat rail- Hiking refers to the maneuver of leaning on one side of the boat or over the water to cause or to counteract heeling. To maintain maximum speed, optimum shape of the boat's hull underwater is achieved by the crew shifting its weight as conditions change.

When boat speed is low, as in a light breeze, friction resistance between the water and the hull is reduced by causing the boat to heel intentionally when the crew sits on the leeward side and the helmsman also places his weight leeward by using the extension provided by the hiking stick. In

heavy wind the crew counteracts excessive heeling by going out on the windward side to hike, or lean over the water.

To be most effective hiking sticks should be moveable in all directions. Additional skill is required to use a hiking stick over simple tiller manipulation. During tacking, for example, the crew is exposed to additional hazards caused by the uncontrolled free movement or sweep of the stick. Prior hiking sticks such as those described in U.S. Patent Nos. 4,262,619 and 3,929,086 addressed these problems by providing means for storing or securing the stick by telescoping the extension shaft and clipping it to the tiller length or retracting it under spring tension for storage within the tiller tube.

My prior patent, U.S. No. 4,656,960, addressed the problem of uncontrolled stick movement by providing an assembly having an axle with vertical and horizontal channels within it which are provided with compression rings to cause friction controlled movement of a yoke and a vertical cylinder located within the axle and locking of the stick attached to the yoke when unattended. While representing a major advancement in the field the assembly required substantial strength to manipulate which placed undue strain on some components during high angle movement, when the stick approaches a position perpendicular to the tiller. The improvement provided by the present invention alleviates these problems.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood by reference to the following description taken in view

of the drawings in which:

FIG. 1 is a perspective view of the stern portion of a sailboat;

FIG. 2 is a perspective view of a preferred embodiment of a hiking stick assembly, with parts in phantom;

FIG. 3 is a perspective exploded view of the embodiment of FIG. 2;

FIG. 4 is an elevational view of the hiking stick assembly of FIG. 2, with parts cut away for clarity.

SUMMARY

Broadly the invention contemplates an assembly having a base attached to a boat tiller carrying a vertically disposed fixed shaft that mounts a vertically rotatable saddle compressed between a pair of compression surfaces about the shaft which has vertical arms that compressively mate with those of another similar saddle, the two saddles positioned on a horizontal axle providing an axis of rotation. The axes of rotation are positioned adjacent to one another. A hiking stick extension member is attached to the center span of the saddle that is not mounted on the fixed shaft. The hiking stick tiller of this invention has improved high angle operation which requires no substantial changes in the force needed to achieve any orientation about the vertical or horizontal axes. The stick responds readily to constant hand pressure but remains in a fixed position when released by the helmsma .

More specifically, this invention provides an improved sailboat hiking stick tiller extension

assembly capable of being manipulated in any vertical or horizontal direction while maintaining a fixed position in any orientation comprising: a base which is mounted on the tiller and having a vertically disposed upstanding fixed shaft carrying an annular shoulder on its upper end and a compression adjusting member at one of its ends; a first saddle having a pair of spaced apart upstanding arms separated by a center span, horizontally pivotally mounted on the annular shoulder through the center span, with the shaft defining a vertical axis of rotation; a pair of compression surfaces mounted on the shaft which are positioned so as to frictionally confine the center span of the first saddle; a second saddle having a pair of spaced apart upstanding arms separated by a center span, its arms mating with the arms of the first saddle and pivotally attached thereto; a horizontally oriented axle having opposing ends, fixed at one end to one arm of a saddle and extending through the mated arms of the saddles to define a horizontal axis of rotation, and having a compression adjusting member at its other end; a second pair of compression surfaces mounted on said axle and frictionally separating the mated arms of the saddles; a spacer sleeve horizontally disposed over the axle between the center spans of the saddles and adapted to maintaining spacing integrity of the saddle arms under converging compressive force; a hiking stick extension member perpendicularly mounted on the center span of the second saddle; the pivot points of said saddles being substantially adjacent to each other.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to the drawings, in FIG. 1,

sailboat 10 is controlled by rudder 14 connected to tiller 19 which carries hiking stick 20 attached to stick assembly 18. Assembly 18 is mounted on a fore portion of the tiller. Hiking stick 20 is grasped in use by the helmsman usually seated on boat rail 16.

In FIG. 2, socket 23 which holds hiking stick extension member 21 is attached to handle 22, shown in phantom, and employs socket head set screw 25 to seize the stick assembly 20. First saddle 24, here depicted as a female saddle, has spaced apart arms 26 and 27 separated by a center span to which socket 23 is perpendicularly attached. Second saddle 30, depicted in this embodiment as the male saddle, has spaced apart arms 31 and 32 which are mated in horizontal fashion between the arms of the first saddle and frictionally fastened in rotatable alignment by horizontal axle 45 (not shown in this view) which also carries compression washers 35a and 35b positioned between the upstanding arms of each saddle. Fixed axle head 28 on axle 45 is positioned on arm 26 of exterior saddle 24. Adjustable lock nut 29 is threaded on the opposing end of the axle. Saddle arm spacer 33 is positioned in contact with the interior or male saddle arms to maintain vertical alignment of the saddle arms when they are subjected to converging or collapsing compressive force applied along the axle. Vertical shaft 36 passes through the center span of saddle 30 which is positioned between compression washers 38a and 38b carried on the shaft and which are retained by fixed flat bolt head 37 attached to the upper end of the shaft. Shaft 36 below the inside saddle is non-circular, for example it may have a lower flattened surface 34 as depicted in this view. The non-circular segment of shaft 36 terminates in non-circular threaded segment 40 at its

lower end which accommodate base plates 41a and 41b fastened to opposing surfaces of tiller 19 by base plate screws 42a and 42b. Lock nut 39 threaded onto the shaft serves to hold the assembly on the tiller, while the base plates cooperating with the non- circular shaft rotationally fix it to the tiller.

FIG. 3 depicts detail of the preferred assembly in which axle 45 carries axle shoulder 44 which mates with port 46 on saddle arm 26 to lock the axle to the one arm. Spacer 33 is depicted as having a channel passing through it to carry axle 45, although the spacer may consist of a sleeve carried on the axle and frictionally held in place between second saddle arms 31 and 32. Spacer 33 is also depicted as having a flat lower side which is important in allowing the pivot points to be placed adjacent to each other. Vertical shaft 36 has annular sector 46 at its upper end. This accommodates the compression washers 38a and 38b and passes through saddle 30 by port 48 to provide the rotational center about which this saddle may pivot.

FIG. 4 best depicts the means by which the assembly brings the pivot points into as close proximity to each other as possible. Spacer 33 carries a flattened axial planar area below the channel through which axle 45 is carried. Bolt head 37 is flattened to require minimum clearance so as to keep the center span of saddle 30 as close as possible. Compression means needed to cause the internal tension producing critical drag force over the saddle components include mechanical elements that exert axial force inwardly to the compression surfaces more centrally located in the assembly. The exertion of uniform bilateral tension is the required result.

As here used, the term "compression" or "compressible" means discretely or molecularly surface deformable upon the application of external bilateral force in comparison to the dimensional changes which occur in the external clamp elements, especially the axle or the shaft. Deformation which becomes visually perceptible will generally be considered excessive. Except in the case of separate compression components, such as washers, any deformation of multi-function parts such as the axle should be confined to their contact surfaces.

As used herein, the term "pivot point(s)" means the point along an axis of rotation which is equidistant between a pair of compression surfaces under substantially equal but opposing and converging force to one another.

It is critical that the pivot points along the shaft vertical axis of rotation and the axle horizontal axis of rotation be placed as close together as possible to achieve uniform and low force high angle movement of the stick.

While the critical aspect of this invention concerns the adjacent placement of the pivot points, that is, placing them in as close proximity as possible, another important aspect is the composition of the compressive or slip elements forming the compression surfaces which produce the desired type of drag force. The compression surfaces include compression/slip washers or alternatively, the moveable surfaces of unitary central compressible elements such as the mating surfaces of the saddles.

A preferred material for fabrication of the compressible parts is polyvinylchloride (PVC) . Any other material which produces smooth, controllable chatter-free silent movement between the saddle

surfaces under high compression is generally suitable. It is highly desirable that the material chosen be resistant to high moisture conditions, corrosion and ultraviolet radiation. Other suitable materials include, but are not limited to, butadiene-styrene polymers, most preferably reinforced with suitable fibers. Such materials include those marketed as K-Resin by Phillips Petroleum. Glass fiber reinforced polymers of this class are also highly suitable. A further material which is suitable for use in this invention is linear polyoxymethylene-type acetal resins including those sold under the trademark Delrin by DuPont. Components manufactured from Delrin 570 resin 2% glass fiber-reinforced homopoly er are easily fabricated by injection molding. Ultraviolet- stabilized glass-filled nylon, particularly 6/6,6/12 30% glass nylon is also suitable. Type 6/6 nylon is the condensation product of hexamethylenediamine and adipic acid. Type 6/12 nylon is made from hexamethylenediamine and dodecanoic acid.

Other suitable materials include metal, glass and wood. The use of lubricating materials, including molybdenum-filled plastics, is disadvantageous because they unduly reduce the drag properties important to the performance of the assembly.

Embrittlement occurring from prolonged exposure to sunlight which is to be expected in the present application may be alleviated by the addition of 2% finely dispersed carbon black which will markedly prolong the life of the polymer components.

While the embodiment depicted by the drawings shows the first or upper saddle as the female member of the mating saddles, the relationship can

obviously be reversed with the upper member being male and the lower saddle being female and carrying non- circular mating port 48.

In operation downward force on hiking stick 20 causes horizontal axis rotation about axle 45. Compressive adjustment to suit the sailor and to provide quiet and smooth controlled movement of the stick is provided by adjustable lock nut 29. Vertical axial rotation is caused by circular movement of the stick about shaft 36 which is adjusted by rotation of adjustable lock nut 39 or bolt head 37.

Coating of the saddle arms or center span, which rotate about the horizontal axis or around port 48 of the lower saddle about the vertical axis, may be accomplished by ways known in the art to replace washers or separate pads as friction elements.

It will be apparent to those skilled in the art that modifications and variations may be made without departing from the scope and spirit of the invention and the following claims.