US3052470A

US3052470A - Towing systems for use in water-sking or ski-yorring

Info

Publication number: US3052470A
Application number: US761826A
Authority: US
Inventors: Pomagalski Jean
Original assignee: Individual
Current assignee: Individual
Priority date: 1957-09-24
Filing date: 1958-09-18
Publication date: 1962-09-04
Anticipated expiration: 1979-09-04
Also published as: CH350232A; FR1184715A; NL97425C

Description

P 1962 J. POMAGALSKI 3,052,470

TOWING SYSTEMS FOR USE IN WATER-SKIING 0R SKI-YORRING Filed Sept. 18, 1958 2 Sheets-Sheet 1 1:21) era-60L Panza/ya, LS1: L

Se t. 4, 1962 J. POMAGALSKI TOWING SYSTEMS Fo'R USE IN WATERSKIING OR SKI-YORRING Filed Sept. 18, 1958 2 Sheets-Sheet 2 QJT Pomajaiosjcb Jay- 3,052,470 Patented Sept. 4, 1962 ice 3,052,470 TOWING SYSTEMS FOR USE IN WATER-SKIING R SKI-YO r Jean Pomagalski, 80 Rue Charles Michels, Fontaine, France Filed Sept. 18, 1958, Ser. No. 761,826 Claims priority, application France Sept. 24, 1957 Claims. (Cl. 272-32) The present invention relates to the sport known as water-skiing.

So far, the towing means necessary for this sport have been confined to motor-boats, which is extremely costly.

Proposals from various quarters, notably France, Great Britain and the U.S.A., have been made to utilize devices featuring an endless towing cable, but such devices have never been put into application for the good reason that they simply are not feasible, having been evidently designed by persons not sufficiently acquainted with waterskiing and having but inadequate knowledge of the problem to be solved.

On the one hand, towing in a straight line is of little or no interest to those who practice this sport; the only interesting feature is the slalom, which is, in fact, forbidden on the ski-lifts used on snow, every effort being furthermore made to render it impracticable by arranging for the tow line to be very high above the ground. In this respect, the present invention has for its object to enable the slalom to be practiced.

On the other hand, and having regard for the considerable speeds currently used, it is unthinkable that the competent authorities would authorize installations in which a danger existed of skiers colliding, at full speed, either with the pylons supporting the cable pulleys or with the bank. In this respect, the present invention has for its object to make it an easy matter to arrange the pulleys at such distance from the pylon as to ensure complete security or, looked at from another standpoint, to allow arranging a greater number of pylons on the shore or arranging certain pylons relatively nearer to the shoe, i.e. over shallower water so as to facilitate installation.

Lastly, it would be entirely illusory to think that this sport could be of the slightest interest if practiced at a speed low enough for the skiers to be able to connect themselves up on to cable. In this respect, too the present invention has for its object a new method of operating systems which use endless-type towing cables.

With the first objects in view, there is provided by the invention a system allowing for the practice of waterskiing or ski-yorring by towing via an endless-type cable driven and guided along a closed circuit above the water by means of pulleys, and to which endless cable are fixed the conventional tow-lines, this system being characterized by the face that the pulleys are supported by pylons through the medium of non-rigid connections, that is to say through the medium of an articulated or flexible connection, equilibrium of each pulley being the result of the pull exerted by the endless cable, on the one hand, and that exerted via the articulated or exible connection.

With the achievement of its final object in view, the invention provides for a method of operation of a system enabling the practice of water-skiing or ski-yorring and comprising an endless-type towing cable, characterized by the fact that at least two speeds are used for the endless cable, one of which is substantially equal to the minimum speed needed to maintain buoyancy of the skier on the surface of the water.

An embodiment of my invention is described hereinafter by way of example only, it being clearly understood that the scope of the invention is by no means limited to the specific form or structural details chosen for illustrative purposes.

In the accompanying drawings,

FIG. 1 is a schematic plan view of the complete installation;

FIG. 2 is an illustration showing a supporting pylon in elevation;

FIG. 3 shows, in elevation, a supporting and tensioning ylon;

FIG. 4 illustrates, in elevation, a supporting pylon which also provides tractive power.

In this example, a path of triangular shape has been chosen for the endless tow cable 1, there being two

pylons

2 and 3 on the bank 4 and one pylon 5 with submerged foundations. The cable is carried by

pulleys

6, 7 and 8, the method of suspension of which is described with reference to FIG. 2. In this latter figure, which relates to pylon 5, the pulley 8 is carried by the arm 9, upon which is articulated, at 10, a cranked lever 1-1, the arm 12 of which constitutes a block for the tension roller 13. The relative position of this roller 13 can be adjusted by means of a screw 18 which is articulated about the arm 9 and which cooperates with a nut integral with the cranked lever 11, thus enabling the pulley 8 to be adjusted relative to the two runs of the cable 1. This method of adjustment is not shown in detail, being well-known per se and of current application.

A flexible support cable 14, one end of which is anchored to the

pylon

5 and 15, passes over the roller 13 and thence over a counter-roller 16 before being wound on to a winch 17 supported by the bracket of the pylon. The bracing guys for the pylon have been designated by the numeral 19.

In actual practice, the distance between

pulleys

13 and 16 will usually be relatively greater than shown in FIG. 2.

The pylon Z is similar to the pylon 5 except in respect to the winch 20 which serves to adjust the cable 21 and which is mounted on a counterweight 22 free to slide along vertical guides 23. By means of winch 20 the position of the counterweight 22 can be changed to accommodate changes of length of cable 1 due to temperature changes or stretching under tension. This apparatus serves to tension the cable 1.

Translational movement of the cable 1 is provided by a motor 24, via a transmission system which is 'ancillarly to the pylon 3. The pulley 7 is of the twin-groove type, one groove 25 taking the cable 1, while the other groove 26 accommodates the movement-transmitting endless cable 27. The pulley is supported by the arm 28, the complete supporting arrangement being the same as that described under reference numerals 11 to 19 in FIG. 2.

The cable 27 passes over the pulley 30 via counterrollers 29, it being possible to interpose a speed-reduction unit (not shown) between the pulley 30 and the motor 24.

The rollers 29 are carried by a link 31 the end of which is slidable, say via a box-threaded sleeve screwed on to a threaded rod 32. This or any other equivalent system allows adjusting the plane defined by the two runs of the cable 27 relative to the plane of the groove 26. The motor is carried by the pylon 3 on a bracket 33 which is slidable along vertical guides 34. If required, the counterweight 35 may be added to contribute to tensioning of the cable 27.

Conventional tow-lines (not shown) for towing the skiers are provided on the cable 1, their fastening points being spaced evenly along the whole length of the cable to which they are secured in the usual way. They serve to secure the usual grip to which water-skiers hold.

A take-0E pontoon or raft 36 is provided, and is preferably located directly upstream of a pulley (in this instance pulley 7) relative to the direction of travel of the cable 1, as indicated by the arrow F.

Let it be imagined that a water skier is on a raft 36 and wishes to grasp a towline 1a so he will be pulled around the course of the tow cable. If the cable 1 is traveling at, say 30 miles per hour, a skier would be jerked from a stationary position to 30 miles per hour movement. If, however, the tow-line where it is fastened to the cable 1, passes pulley 7 until the tow-line extends from

flight

7, 8 of cable 1 at right angles to cable 1 to raft 36, then the skier, having his tow-line taut, the speed of movement of the tow-line relative to the skier is momentarily zero. As the connection between the towline and cable 1 moves toward pulley 8, and the angle between the vertical plane of the tow-line and the vertical plane Of the cable 1 changes from 90 to the speed of the skier holding onto the tow-line will increase from zero to 30 miles per hour.

The sines of the successive vertical angles between the tow-line and the tow cable as they change from 90 to 0, multiplied by the 30 (speed of the tow cable) will give the relative speed between the skier and the cable at successive points. It is clear that the drive impulse is applied in a vertical plane forming a notable (i.e. large) angle with the vertical plane of the cable and not in a vertical plane passing through the cable, when the skier wants to start from the raft 36 so he will not be snatched from a dead standstill to full speed.

According to the invention, the device is operated at two speeds at least, one of which is just suflicient to provide the necessary buoyancy for the skier on the surface of the water during the time required for the other skiers to seize hold of their respective tow-lines. Once all the skiers have connected themselves up, the normal sporting speed or speeds are the adopted. For stopping, speed is reduced to the connecting-up speed, to allow the skiers to relinquish hold at will, either at the nearest point to the shore or on passing in front of the pontoon.

It will be noted that the apparatus described herein above and the method of putting it into operation are applicable on snow, as a substitute for the sport known as ski-yorring, which involves substantially the same problems.

What I claim is:

1. In a device for the practice of water skiing or skiyorring, an endless tow cable, a plurality of pylons, open sided pulley means supported from said pylons in driving relation with said tow cable with the open side of said pulleys downward for driving and guiding said tow cable, tow lines attached to said tow cable, tensioning means associated with one of the pylons, flexible means to connect the pulleys to the pylons, whereby the equilibrium of each pulley is the result of the pull exerted by said endless tow cable tensioned by said tensioning means and of the reaction of said flexible connecting means, and a driving pulley operatively connected to one of the open sided pulleys, a pair of guide rollers mounted on the corresponding pylon, driving means vertically slidably mounted on the corresponding pylon, and an endless driving cable engaging said driving pulley and driven by said driving means, a portion of said endless driving cable being guided into a path in a plane parallel to said corresponding pylon by said guide rollers and engaging said drivingpulley.

Z. In a device as claimed in claim 1, means to adjust the effective length of said flexible means to thereby adjust the distance between a pulley and the corresponding pylon.

3. A device as claimed in claim 1, in which said flexible means is a connecting cable anchored at one extremity to the corresponding pylon, and including a winch fixed in position on which the other extremity of the connecting cable is wound, whereby the distance between the pulley and the pylon may be adjusted.

4. In a device for the practice of water skiing or skiyorring, an endless tow cable, a plurality of pylons open sided pulley means supported with the open side downward for driving and guiding said tow cable from said pylons in driving relation with said tow cable, tow lines attached to said tow cable, and tensioning means associated with one of the pylons and including a tensioning pulley to tension said cable, flexible means to connect the pulleys supported from the other pylons to the corresponding pylons, whereby the equilibrium of each pulley is the result of the pull exerted by said endless tow cable tensioned by said tensioning means and of the reaction of said flexible connecting means, the tensioning means for the endless cable comprising a connecting cable anchored at one extremity to the corresponding pylon, and engaging a roller on said tensioning pulley, a roller on said corresponding pylon over which said connecting cable is passed, a counterweight attached to the other extremity of said connecting cable by a winch mounted on said counterweight vertically movable with respect to said pylon adapted to adjust the length of said connecting cable.

5. In a device for the practice of water skiing or skiyorring, an endless tow cable, a plurality of pylons, open sided pulley means supported from said pylons arranged to form the tow cable into a polygonal course, said pulley means being in driving relation with said tow cable, the open side of said pulleys being disposed downward for driving and guiding said tow cable, tow lines attached to said tow cable, and tensioning means associated with one of the pylons and including a tensioning pulley to tension said cable, flexible means to connect the pulleys supported from the other pylons to the corresponding pylons, whereby the equilibrium of each pulley is the result of the pull exerted by said endless tow cable tensioned by said tensioning means and of the reaction of said flexible connecting means, and a driving pulley operatively connected to one of the open sided pulleys, a pair of guide rollers mounted on the corresponding pylon, driving means vertically slidably mounted on the corresponding pylon, and an endless driving cable engaging said driving pulley and driven by said driving means, said endless driving cable being guided into a path in a plane parallel to said corresponding pylon by said guide rollers and engaging said driving pulley.

References Cited in the file of this patent UNITED STATES PATENTS 381,675 Casselman Apr. 24, 1888 443,492 Bentley Dec. 30, 1890 757,952 McKay Apr. 19, 1904 1,546,031 Schofield July 14, 1925 1,852,224 Test Apr. 5, 1932 2,677,331 Hauseman May 4, 1954 FOREIGN PATENTS 803,496 France July 6, 1936 1,019,691 France Nov. 5, 1952