What is claimed
1. A fastener for fastening a ski boot binding to a ski, wherein the ski is provided with a bore formed through its thickness, the bore having a downwardly open, enlarged section having an upper surface, the fastener comprising an upright, threaded metal shank for insertion in the bore and having at its lower end a transverse, outwardly extending, flat-bottomed metal flange receivable in the downwardly open, enlarged section of the bore, a shapable, flat-bottomed plastic plug on the flange's bottom surface, the fastener including a cap engageable with the upper surface of a ski boot binding and having threads engageable with the threaded shank, whereby the cap may be threaded from above onto the shank, containing therebetween and securely clamping together a ski boot binding and a ski.
2. The fastener of claim 1 wherein the shank has a roughened, cylindrical outer surface for adhering, with an adhesive, the inner cylindrical bore formed in a ski to the shank.
3. The fastener of claim 1 wherein the thickness of the flange is not greater than about 1 mm and wherein the thickness of the flange and plug together is not less than about 1 mm.
4. The fastener of claim 3 wherein the shank is exteriorly threaded adjacent its upper end and is of sufficient length to extend through a bore formed through the thickness of a ski at the center of the latter, and wherein the cap comprises a nut threadable onto the threaded shank and engageable with the upper periphery of mounting hole in a ski boot binding.
5. Method for remounting a ski boot binding without relocation upon a ski from which the binding had been pulled to leave a damaged screw hole in the ski, the method comprising
6. The method of claim 5 including the step of providing an adhesive between the fastener and bore so as to form a permanent, waterproof bond therebetween.
7. Method for mounting a ski boot binding upon a ski, comprising
8. The method of claim 7 wherein the ski includes a core, a lower fiberglass layer, and a bottom, snow-contacting plastic layer, and wherein the enlarged, downwardly open section of the bore is extended upwardly to approximately the lower surface of the fiberglass layer.
9. The method of claim 7 including the step of providing an adhesive between the fastener and bore so as to form a permanent, waterproof bond therebetween.
10. In combination,
11. The combination of claim 10 including, between the fastener and bore of the ski, an adhesive forming a waterproof bond therebetween.
12. In combination,
BACKGROUND OF THE INVENTION
Skiing, and particularly professional skiing, is an extremely rugged sport in which skis are often broken or damaged. The bindings of a ski, which are designed to hold the sole of a ski boot firmly against the ski, are often subjected to extreme stresses during, for example, ski races. Such bindings ordinarily are held to skis by means of small screws which pass through screw holes in the binding and are threaded part way through the thickness of the ski. Although this method of fastening bindings to skis is often acceptable for amateur skiers, I found through personal experience that the large stresses which are placed on ski bindings by professional skiers often cause the bindings to pull from the skis, and especially from fiberglass skis, the small wood screws being ripped from the wooden core of the skis and leaving unsightly, broken, upper ski surfaces. Such equipment failures ordinarily lead to expensive repair or replacement of the skis. Of greater importance, equipment failures of this type can be highly dangerous to skiers, particularly during high speed races or when difficult skiing maneuvers are performed.
Prior to my invention, a ski from which the binding screws had been pulled would either be discarded as useless or would be repaired by refastening the binding to the ski with similar wood screws, the binding being spaced forwardly or rearwardly from its original position. Of course, the other binding members on a pair of skis would be similarly relocated. The resulting repaired ski would be somewhat weakened because of the damaged portion of the ski, and the relocation of the binding ordinarily greatly changed the performance of the ski, the latter being especially noticeable with racing skis.
A fastener for fastening bindings to skis which would have great strength to resist the high stresses tending to pull the bindings from the skis and which could be used to repair skis from which bindings have been ripped without relocation of the bindings would be highly beneficial to the sport of skiing and would greatly reduce accidents in professional skiing resulting from the loosening or tearing of bindings from skis. fastener as when screws holding a binding to a ski have been pulled out or as original equipment in combination with a ski and binding. The fastener includes an upright, threaded shank insertable in a bore formed through the thickness of a ski, the shank having at its lower end a transverse, outwardly extending, flat-bottomed flange which is received within a downwardly open enlargement of the bore in the bottom-most, snow-contacting layer of a ski. At its bottom, the flange includes a smoothable, flat-bottomed plug which may be of plastic or the like, the plug at least partially being received within the enlarged portion of the bore. Cap means comprising a cap having threads for engaging the threaded shank and configured to engage the upper surface of a binding is provided, the cap holding the binding firmly against the upper ski surface. In another embodiment, the invention relates to a ski having a binding mounted thereon by the thus-described fastener.
In yet another embodiment, the invention relates to a repair method for remounting a binding upon a ski from which one or more binding screws have been pulled to leave one or more screw holes. The method comprises enlarging each screw hole to form a bore extending through the thickness of the ski, the bore terminating downwardly in an enlarged, downwardly open section having a flat upper surface in the bottom, snow-contacting layer of the ski. A fastener is placed in the bore from beneath, the fastener having a shank threaded at its upper end and having a transverse, outwardly extending, flat-bottomed flange at its lower end fitting within the enlarged terminal end of the bore, the flange including at its bottom surface a plug at least partially received within the enlarged end of the bore. A ski binding is oriented on the upper surface of the ski with a screw hole of the binding in alignment with the fastener shank, and a threaded cap is threaded downwardly upon the binding and onto the shank to hold the binding tightly onto the ski and to press into place any portions of the ski surrounding the screw hole which may have been displaced or distorted when the binding screw was pulled from the ski. The plug may thereafter be trimmed so that its bottom surface is smooth and flush with the bottom surface of the ski for sliding across snow. If desired, a hardenable, water-proof liquid adhesive may be poured between the bore and the fastener shank, and particularly at the upper, often disrupted end of the bore to, adhere the disrupted portions of the ski in place, to improve the strength and rigidity of the fastening, and to render the latter water-proof.
BRIEF DESCRIPTION OF THE DRAWING
FIGS. 1-4 are cross-sectional, broken away views of a ski showing sequential steps in the mounting of a binding to a ski from which the binding had been ripped;
FIG. 5 is a perspective view of the fastener of the invention appearing also in FIGS. 3 and 4;
FIG. 6 is a cross-sectional view of a ski and binding in an intermediate stage of mounting of the binding to the ski and employing a modified fastener; and
FIG. 7 is a perspective, exploded view of the fastener shown in FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A "fiberglass" ski 14, for which the present invention is particularly desirable, is shown in FIGS. 1-4 and 6 and comprises an upper layer 14.1 of protective plastic such as vinyl or the like covering an inner layer 14.2 of fiberglass. At its bottom surface, the ski is provided with a vinyl snow-contacting, running surface 14.4 above which is an inner layer of fiberglass 14.5. The fiberglass layers 14.2, 14.5 are bonded to an internal wooden core 14.3 which, although shown for clarity as a single wooden element, ordinarily is in the form of a hardwood laminate. The fiberglass layers provide much of the strength of the ski and largely control the flexibility of the ski, the latter being of great importance in professional skiing.
As shown in FIG. 1, the pulling or ripping out of a binding screw from the ski may result in a severe disruption of the upper surface of the ski in the vincinity of the screw hole 16, the upper plastic and fiberglass laminae 14.1, 14.2 being pulled upwardly away from the core of the ski and leaving a jagged screw hole 16. Several small pieces of wood are shown as remaining adhered to the under surface of the fiberglass layer 14.2 at the sides of the screw hole. The damage shown in FIG. 1 is small as compared to the extensive damage which is often caused by the ripping away of ski bindings.
Turning now to FIG. 2, I first bore a hole 14.6 through the thickness of the ski, using the screw hole 16 as a centering guide. The bottom, snow-contacting layer 14.4 of the ski about the periphery of the hole 14.6 is then removed to form a circular recess 14.7, the recess having as its upper surface about the hole the bottom surface of the fiberglass layer 14.5. Although the recess 14.7 may be square or hexagonal or have any other particular shape, I prefer the recess to be generally circular for ease in employing the fastener of my invention. A representive diameter for the hole 14.6 may be on the order of 3/16 inches, or 0.45 mm, and the diameter of the recess 14.7 extending about the lower periphery of the hole may be, for example, 3/8 inches or approximately 10 mm. The thickness of the bottom, snow-contacting layer 14.4 of a typical ski may be on the order of approximately 3/64 inches, or about 1 mm.
Referring next to FIG. 3, I thereafter insert from the bottom of the ski and through the hole 14.6 a fastener of my invention, designated generally as 18. The fastener 18, shown in detail in FIGS. 3-5, comprises an upright shank 18.1 having an upper, threaded end 18.2 and a lower, outwardly extending flange 18.3 having a desirably circular configuration closely fitting within the recess 14.7 in the bottom layer 14.4 of the ski. The flange includes at its bottom a plug 18.4 of vinyl plastic or the like which when smoothened is slippery on snow. The thicknesses of the flange 18.3 and plug 18.4 are such that when the flange 18.3 is urged forcefully into the recess 14.7 in the bottom surface of the ski, the plug is at least partially received within the recess, and desirably extends downwardly out of the recess a very slight amount, as shown in FIGS. 3 and 4. The total heighth of the fastener is slightly greater than the thickness of the central portion of a ski plus binder; eg, on the order of 2.5 - 3.0 mm. Into the fissures 16.1 at the upper end of the bore 14.6 is poured a hardenable, liquid, water-proof adhesive such as any of the widely sold, two-part epoxy adhesives. The adhesive may also, if desired, be coated upon the surface of the shank 14.6 and on the upper surfaces of the flange 18.3 so as to form permanent, waterproof bonds between the ski and the mating surface of the flange and shank.
The binding 12 is then placed on the ski with a countersunk screw hole of the binding aligned with the shank 18.1. In the embodiment depicted in FIGS. 3 and 4, the shank 18.1 extends upwardly through the screw hole and binding 12. A threaded cap, such as nut 18.5 is then threaded tightly onto the shank 18.1 and against the countersunk upper surface of the binding to hold the binding securely and rigidly in place. As shown in FIG. 4, the nut 18.5 is seated downwardly in the countersunk screw hole of the binding to bear downwardly and outwardly on the tapered upper periphery of the screw hole. The top of the nut 18.5 projects only a short distance above the upper surface of the binding screw hole, and any portion of the shank which may project above the upper surface of the nut is cut or abraded away so that the shank is substantially flush with the upper surface of the nut to avoid snagging on clothes or the like. It will be understood that the nut may have a lower conical surface mating with the tapered upper periphery of the binding screw hole, or a conical insert may be employed, or the upper periphery of the screw hole may be provided with a configuration matching that of the lower surface of the nut, all for the purpose of providing surface-to-surface contact between the nut and the binding.
If at this point the lower surfaces of the plugs 18.4 are either spaced inwardly of or are flush with the bottom surface of the ski, the ski is ready for immediate use. Any protrusion of the plugs 18.4 below the bottom surface of the ski may be trimmed to render the plugs flush with the bottom ski surface. When the plug is of thermoplastic material such as a vinyl plastic, I prefer to soften or locally melt the plug about its periphery by the application of heat from an iron or the like, and flow the edges of the plug into the very small annular opening normally found between the periphery of the plug and the periphery of the recess 14.7 formed in the bottom ski layer. Skis which have been repaired in accordance with my invention have been found by me to perform as well after the repair as before the repair, the very strong fastening thus provided not only lending strength to the fastening but also confidence to the skier.
Since, as noted above, it is the fiberglass layers 14.2, 14.5 which are primarily responsible for lending strength to, and controlling flexibility of fiberglass skis, it is important that the fiberglass layer be disturbed as little as possible. The recess 14.7 which is formed in the bottom layer of the ski should desirably extend only to the lower surface of the fiberglass layer 14.5. This can readily be accomplished by employing an abrasive disc of the diameter desired for the recess 14.7, the disc being mounted on an ordinary hand drill and having a central projection for extending into the bore 14.6 to center the disc with respect to the bore. The bottom layer 14.4 of the ski may thus be abraded slowly and in increments until the surface of the fiberglass inner layer has been reached. Since the thickness of the bottom layer 14.4 may vary from ski to ski, and may become thinner due to repeated useage of skis, I desire to form the recess 14.7 very carefully so as to avoid cutting any significant amount into the figerglass layer. If a large number of skis having bottom layer of constant thickness are being worked upon, however, as when the fastener of the present invention is employed for continuously mounting identical bindings upon identical skis, I may provide the above-described abrasive disc with a depth control such as an outwardly extending flange, preventing the disc from removing more than a predetermined thickness of the bottom ski layer. It will be understood by those skilled in the art that in place of an abrasive disc, I may use drill bits of various configurations to accomplish the recess-forming operation. To insure that the plug may be trimmed to be flush with the bottom surface of the ski regardless of variances in thickness of the bottom ski layer, I prefer to maintain the total thickness of the flange and plug at not less than about 1.0 mm, and the flange minus the plug is desirably 1 mm or less in thickness.
Another embodiment of the fastener of my invention is shown in FIGS. 6 and 7. The fastener, designated generally as 18', includes an upright shank 18.1 having an upwardly open, internally threaded bore 18.2 which may extend less than the full length of the shank, as shown in FIG. 6. The shank terminates downwardly in an outwardly extending transverse flange 18.3' furnished with a plug 18.4' on its lower surface. The total heighth of the shank, flange and plug is less than the thickness of the central portion of a ski and may be, for example, on the order of 1.2- 1.8 mm. A threaded cap, in the form of a threaded, upright shaft having an expanded upper end, such as metal screw 18.5', is threadingly received into the shank 18.1 and has an expanded, slotted head 18.6 for bearing downwardly upon the countersunk surface of a screw hole of a binding 12. In preparing a ski to receive a fastener of this embodiment, I first bore a hole completely through the thickness of the ski, the hole having a diameter very slightly larger than that of the threaded portion of the screw 18.5. A second hole is then bored from the bottom of the ski upwardly, the second hole desirably terminating short of the upper fiberglass layer 14.2 and having a diameter approximately the same as the outer diameter of the fastener shank 18.1. I thereafter form an enlarged, transverse recess in the bottom most layer 14.4 of the ski, as described above with reference to FIGS. 1-4. The shank 18.1' of the fastener 18' is then forced upwardly from the bottom of the ski into the bore, the transverse flange 18.3' becoming seated against the bottom surface of the fiberglass layer 14.5, as depicted in FIG. 6. A hardenable, liquid, water-proof adhesive of the type described above may then be poured into fissures 16.1 which may have been formed when the binding was pulled from the ski. The binding 12 is then aligned with a screw hole of the binding in line with the shank 18.1', and the metal screw 18.5' is then screwed downwardly through the binding and into the shank 18.1'. The lower surface of the binding 12 presses against the upper surface of the ski, forcing the previously disrupted area surrounding the screw hole to be pressed into place. The bottom surface of the plug 18.4' which ordinarily protrudes very slightly from the under surface of the ski may be smoothened, as described above.
The fastener 18' depicted in FIGS. 6 and 7 has the advantage that the enlarged head 18.6 of the metal screw is received substantially fully within the countersunk screw hole of the binding, thereby providing the binding with a smooth upper surface. Because of the doubly bored hole in the ski, however, and because of the more difficultly fabricated shank and flange, the fastener of FIG. 7 is slightly more difficult to use and slightly more expensive to make than is the fastener of FIG. 5.
Referring now to FIGS. 5 and 7, which depict fasteners employed in FIGS. 1-4 and 6, the fasteners desirably are made of metal such as aluminum, the shank and flange being machined from an integral metal blank to avoid weldments or other points of weakness. The flange preferably is not more than about 1 mm in thickness so that when the fastener is inserted into a properly prepared ski, as shown in FIGS. 3, 4 and 6, the bottom surface of the metal flange is depressed slightly inwardly of the botttom surface of the ski, thus permitting the plastic button to be received and retained at least partially within the recess 14.7. The button may be cut from a sheet of vinyl plastic or other material, and is firmly cemented, melted, or otherwise fastened to the bottom surface of the flange. Desirably, the bottom surface of the metal flange is scored or abraded to provide some physical adherence to the button 18.4. The threaded cap, represented as a threaded nut 18.5 in FIGS. 4 and 5 and as a metal screw in FIGS. 6 and 7, may conveniently be made of steel. If desired, the outer, cylindrical surface of the shank 18.1, 18.1' may be roughened and an adhesive as described above may be employed to provide an adhesive bond between the confronting surfaces of the shanks and the holes within which the shanks are received, thereby further improving the strength and water-resistance of the resulting connection between the binding and ski. As an alternative, the shanks may be provided with smooth outer surfaces which may be waxed to slip easily within the ski holes. With the latter embodiment, the fastener may be replaced, if necessary, with another fastener of the invention with considerable ease, and breakage of the fastener is far less likely to cause significant damage to the ski.
Although the fastener of my invention is primarily intended for use with fiberglass skis, it will be understood that the fastener is applicable as well to wooden and metal skis. With the latter mentioned skis, the bore formed through the ski thickness is enlarged at its bottom end a short, predetermined distance, eg; 1 mm, for reception of the flange and plug of the fastener with the plug protruding slightly from the lower surface of the ski.
With any ski, my fastener provides a far better and more reliable fastening between a ski and ski binding then has been available prior to my invention. My fastener is also more desirable in that a torn off binder may be remounted to a ski in its precise, original position, thus preserving the original performance of the ski.
While I have described a preferred embodiment of the present invention, it should be understood that various changes, adaptations, and modifications may be made therein without departing from the spirit of the invention and the scope of the appended claims.