Patent Publication Number: US-3878576-A

Title: Water ski slalom course and method therefor

Description:
United States Patent Suyderhoud 1 1 Apr. 22, 1975 WATER SKI SLALOM COURSE AND METHOD THEREFOR [76] Inventor: Jaap Suyderhoud, PO. Box 2052,  
 Redding, Calif. 96001 [22] Filed: May 20, 1974 [21] Appl. No.: 471,565  
 [52] [1.8. CI. 9/8 R; 114/235 WS; 272/1 B [51] Int. Cl B63b 21/52 [58] Field of Search..... 9/8 R; 114/235 WS; 272/32, 272/56.5 SS, 1 B  
 [56] References Cited UNITED STATES PATENTS 2.203.894 6/1940 Cooke 9/8 R ENTRANCE GATES ll 3,826,494 7/l974 Wainwright et al. 272/1 B X Primary liraminer-George E. A. Halvosa Attorney, Agent, or F [rm-Flehr, Hohbach, Test, Albritton &amp; Herbert [57] ABSTRACT A water ski slalom is provided having guide buoys and turn buoys which utilizes a single anchor cable to which the guide buoys are affixed by an aluminum cross arm. The cross arm is maintained perpendicular to the anchor cable by a diamond-shaped cable arrangement. The turn buoys are affixed to the cross arm by weighted wooden beams.  
 14 Claims, 5 Drawing Figures TURN BUOY 6 LAKE BOTTOM P.-.TENTED 5 3,878,576 snmaq s TURN BUOY GUIDE BUOYS FHG. 3 23 28 STEEL CABLE l5 34 ALUMINUM &#39;u&#39; CLAMP .l  
 &#39; as CABLE STOP WATER SKI SLALOM COURSE AND METHOD THEREFOR BACKGROUND OF THE INVENTION The present invention to directed to a water ski slalom course.  
  Referring to FIG. 1. a standard water ski slalom course includes guide buoy pairs 10 through which a towing power boat travels along a centerline towing the slalom skier. The skier enters the course through the entrance gate buoys ll. slaloms around the six turn buoys I-6 and then exits through the end gate buoys 12. The path of the skier is shown by line 13. Since such course is used for competition purposes it is important that all the buoys accurately maintain their relative locations with rcspect to each other and with respect to the centerline along which the towing line travels. Since the course is. of course. located on water it should be designed so that installation is simple. Once installed. the course should be relatively immune to small changes in water level. winds and currents. In addition. the course should be easily submersible in its entircty so that it does not have to be removed after each use.  
  One type of course used in the past was to anchor each of the buoys individually. This was time consuming. difficult. especially in deep water. and did not maintain accurate relative spacing between buoys.  
  Another type of course arrangement used several cables for each line of guide buoys and turn buoys. Again this was a cumbersome arrangement and suffered the same disadvantages as separate buoys.  
  The use of a single anchor cable has been attempted but was defective in not providing for accurate spacial relationships between the centerline or anchor line of the course and the guide and turn buoys. In addition. it was cumbersome to install.  
 OBJECTS AND SUMMARY OF THE INVENTION It is, therefore. an object of the present invention to provide an improved water ski slalom course.  
  It is another object of the invention to provide a slalom course as above which is simple to install.  
  It is another object of the invention to provide a slalom course where the guide and turn buoys are maintained in accurate spacial relationship with the centerline of the course.  
  It is another object of the invention to provide a slalom course which is easily removed or submerged.  
  It is another object of the invention to provide a slalom course which includes guide buoys which are resistant to snagging by the tow rope.  
  It is another object of the invention to provide a slalom course which has simple installation.  
  It is another object of the invention to provide an improved method of installing a water ski slalom course.  
  In accordance with the above objects there is provided a water ski slalom course having turn buoys and guide buoy pairs fixed in a predetermined layout. The guide buoys lie along a centerline along which a boat towing the water skier moves. The turn buoys serve as slalom gates for the skier. An anchor line extends along the centerline of the course and is fixed at both ends. A plurality of rigid cross arm means space the two buoys of each pair of guide buoys a sufficient distance to allow passage of the boat with each of the guide buoy pairs lying in a predetermined plane. A&#39;plurality of means are provided for fixing the planes perpendicular to the anchor line. A plurality of beam means each have one end rigidly affixed to the cross arm means and are colinear therewith. with the other end holding down one of the turn buoys. The beam means have a positive buoyancy and include negative buoyancy weights affixed to the beam means to submerge them in the water.  
  From a method standpoint there is provided a method ofinstalling a water ski slalom course having an anchor cable along the centerline of the course with guide buoy pairs affixed thereto and spaced from each other by cross arms. Turn buoys are respectively attached to the guide buoys by buoyant beams. The method comprises the following steps. The guide buoys are hung on the cross arms and the cross arms are attached to the anchor cable. The turn buoys are then attached to the beams. Two anchors at the ends of the centerline of the course are provided. The cable is towed with the cross arms and guide buoys and attached to each end to the anchors placing a high tension on the cable. The beams are towed and are respectively attached to the cross arms.  
 BRIEF DESCRIPTION OF THE DRAWINGS DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The typical water ski slalom course which has been described in connection with FIG. 1 has a portion thereof shown in greater detail in FIG. 2. The course is anchored. for example. to a lake bottom at only the two anchor points 14 and 16. Cable 15 lying along the centerline of the course is preferably of galvanized steel with a diameter of three thirty-seconds inch and has its ends attached to the anchors by 3% inch polypropylene line 17. Depending on the water depth. more or less polypropylene line 17 must be used so that the maximum angle with the horizontal is less than 20. This is to maintain the entrance and end gates 11, I2 at water level. Since the breaking strength of the cable combination is 1200 pounds the cable should be anchored with a high tension in order to maintain the placement of the course.  
  Guide buoys I0 and gate buoys I I, 12 are fixed to the ends of rigid right cross arms 18. These are preferablyconstructed of L-shaped angle aluminum. The cross arms provide for accurate spacing of the guide buoys I0. The turn buoys are attached to one end of beams 19 with the other end of the beams being rigidly affixed at points 21 to cross arms I8 and colinear therewith. Beam l9&#39;is preferably constructed of a buoyant wood such as 2 X 2 Douglas fir and therefore weighted down so that it is maintained submerged 6 feet below the surface of the water by weights 22 and 23. As will be explained below, the natural positive buoyancy ofbeam 19 is an aid toward easy installation of the course.  
  Alternatively. beam 19 may be constructed of fiberglass which has essentially a neutral buoyancy. Depending on the type of fiberglass used. no weight or minimum weights may be provided to submerge the beam along with its associated buoys. In any case. beam 19 must be relatively rigid in order to maintain the spacial location of the turn buoys with respect to the cable 15, which lies along the centerline of the course. and to the guide buoys 10. For the same reason. the aluminum cross arm must be relatively rigid.  
  FIG. 3 illustrates the beam 19 and its coupling to alu minum cross arm 18 and their relationship to the turn and guide buoys. As indicated. the entire structure is normally submerged 6 feet below the surface of the water. Guide buoys 10 are of cylindrical construction so that the tow cable does not snag on them while the skier is proceeding through the course. They are composed of solid foam. A typical length of the cylindrical buoys is 18 inches with the greater portion of the buoy being submerged; for example 10 inches as compared to 8 inches which are exposed above the water level. This is believed to provide an optimum resistance to snagging.  
  The weights 22 and 23 are provided by 1 gallon jars filled with ready-mix cement.  
  The normal positive buoyancy of beam 19 and the hanging of the weights 22 and 23 near the ends of the beam produce a tendency of the beam to bend as shown by the dashed line 19&#39; due to the buoyant effect of the water indicated by the arrows 24. Since this occurs in a vertical plane. the location of the turn buoy in the same vertical plane as the guide buoys 10 is maintained. Moreover. as will be discussed below. this vertical plane is preferably maintained perpendicular to the centerline of the course or anchor cable 15.  
  Because of the length of beam 19, it is normally constructed of two separate portions connected together with a relatively rigid splice 26. This may be provided with angle aluminum with a pair of steel clamps. Similarly. a relatively rigid coupling is provided at 27 between the aluminum angle arm 18 and beam 19 by a pair of stainless steel clamps.  
  As illustrated both in FIGS. 1, 2 and FIG. 4 in greater detail. means are provided for coupling the anchor cable to the cross arms by a diamond-shaped cable arrangement. Specifically. fixed to anchor cable I5 for each of the guide buoys 10 and the gates 11. 12 are short segments 28. These are fastened to the continuous cable 15 by. for example, NICO (trademark) cable fasteners at points 29 and 31 as illustrated in FIG. 2. Cable 15 and segment 18 are spread and symmetrically clamped to the cross arms to provide the diamond shaped arrangement.  
  FIG. 4 illustrates the detailed fastening of cable 15 and segment 28 to aluminum cross arm 18 at points 3] and 32. This is accomplished as illustrated in detail in FIG. 5 by a cable stop 33 which may be of a NICO (trademark) type through which the cable 15 runs and is fixed thereto. In turn cable stop 33 is fastened on top of the cross arm 18 by an aluminum U-clamp 34 and stainless steel nut and bolt combination 36.  
  The diamond-shaped arrangement where the arms of the diamond are of equal length is believed to provide for superior stability of the guide buoys and turn buoys in order to maintain the vertical plane in which these buoys lie perpendicular to the anchor cable or the center line of the course. However, alternatively the dia- 4 mond-shaped arrangement might be replaced by a rigid arm which is welded or attached cross wilse to the cross arm 18 at its midpoint with the anchor cable affixed to the ends.  
  The course illustrated in FIG. 2 may be easily installed by the following steps.  
  While on shore. if the course is to be set up on a lake. for example. the guide buoys are first hung on the cross arms by nylon lines. These lines would be approximately 6 feet in length. Next. the two portions of the wood beam 19 are spliced to one another and a turn buoy attached at one end of each beam.  
  The cross arms are then attached to the anchor cable which normally has been precoiled leaving exposed the cable and short segments suitable for forming the diamond-shaped arrangements as discussed above.  
  Two anchors at the proper distances in the water where the course is to be set out are placed. Thereafter. the cable with the cross arms and guide buoys attached thereto is towed to the course site and the ends of the cable attached to the anchors. Relatively high tension should be placed on the cable by a trailing boat. The beams are also towed with the turning buoys attached and they are attached to the respective cross arms. At this time the beams are properly weighted. The course is now ready for use.  
  If it is desired to temporarily discontinue the use of the course. the turn buoys may be disconnected and the anchor cable weighted to overcome the buoyancy of the guide buoys to submerge the entire course. It is also apparent that if any of the buoys accidently disconnect. that portion of the course will submerge further thus preventing any navigational hazards.  
  In summary, the present invention has provided an improved slalom course for water skiers and an improved method of installation therefor.  
 I claim:  
  I. A water ski slalom course having turn buoys and guide buoy pairs fixed in a predetermined layout said guide buoys lying along a centerline along which a boat towing the water skier moves said turn buoys being slalom gates for the skier said course comprising: an anchor line extending along the centerline of said course and fixed at both ends; a plurality of rigid cross arm means for spacing the two buoys of each pair of guide buoys from each other a sufficient distance to allow passage of said boat each of said guide buoy pairs lying in a predetermined plane; a plurality of means for fixing said planes perpendicular to said anchor line; a plurality of beam means each having one end rigidly affixed to said cross arm means and colinear therewith and the other end holding down one of said turn buoys said beam means having a positive buoyancy and including negative buoyancy weights affixed to said beam means to submerge them in said water.  
  2. A water ski slalom course having turn buoys and guide buoy pairs fixed in a predetermined layout said guide buoys lying along a centerline along which a boat towing the water skier moves said turn buoys being slalom gates for the skier said course comprising: an anchor line extending along the centerline of said course and fixed at both ends; a plurality of rigid cross arm means for spacing the two buoys of each pair of guide buoys from each other a sufficient distance to allow passage of said boat each of said guide buoy pairs lying in a predetermined plane; a plurality of means for fixing said planes perpendicular to said anchor line, each of such means including a diamond-shaped cable arrangement coupling said anchor line to said cross arm means; a plurality of beam means each having one end rigidly affixed to said cross arm means and colinear therewith and the other end holding down one of said turning buoys.  
  3. A slalom course as in claim 1 where said course is anchored solely at said ends of said anchor line.  
  4. A slalom course as in claim 1 where substantially all of said guide buoys arc cylindrical.  
  5. A slalom course as in claim 4 where said cylindri cal guide buoys have a greater portion submerged in said water.  
  6. A slalom course as in claim 2 where said beam means have a substantially neutral buoyancy.  
  7. A slalom course as in claim 6 where said beam means are constructed of Fiberglass.  
  8. A slalom course as in claim I where said beam means are constructed of wood.  
  9. A slalom course as in claim 1 where said beam means in combination with said weights. said cross arm means, said means for fixing said planes. and said anchor line have a negative buoyancy whereby such combination or a portion thereof will submerge further if any of said buoys is disconnected.  
  10. A slalom course as in claim 2 where said shaped cable arrangement is formed from short segments of wire connected at both ends of each segment at spaced locations on said .anchor line. such locations corresponding to the spacing of said guide buoy pairs. and includes fastener means for spacing said short segments from said anchor line by symmetrically clamping said anchor line and the midpoint of said segments to each of said cross arms.  
  ll. A slalom course as in claim 1 where said weights are affixed near the two ends of said beam means.  
  12. A method of installing a water ski slalom course having an anchor cable along the centerline of the course with guide buoy pairs affixed thereto and spaced from each other by cross arms and having turn buoys respectively attached to said guide buoys by buoyant beams said method comprising the following steps: (a) hanging said guide buoys on said cross arms; (b) attaching said cross arms to said anchor cable; (c) attaching said turn buoys to said beams; (d) providing two anchors at the ends of the centerline of the course; (e) towing said cable with said cross arms and guide buoys and attaching said cable at each end to said anchors placing a high tension on said cable; (f) towing said beams and respectively attaching them to said cross arms.  
  13. A method as in claim 12 where steps (a) and (b) are accomplished on shore.  
 14. A method as in claim 12 where said beams are weighted before attaching to said cross arms.  
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