US3113550A

US3113550A - Water skiing

Info

Publication number: US3113550A
Application number: US142846A
Authority: US
Inventors: John E Omer
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-10-04
Filing date: 1961-10-04
Publication date: 1963-12-10
Anticipated expiration: 1980-12-10

Description

Dec. 10, 1963 J. E. OMER 3,113,550 WATER SKIING Filed Oct.- 4. 1961 2 Sheets-Sheet 1 A if J. E. OMER WATER SKIING Dec. 10, 1963 Filed Oct. 4, 1961 2 Sheets-Sheet 2 United States Patent 3,113,550 WATER SKEEJG John E. Omar, York Harbor, Maine (1595 Holton Place, Charieston, S.C.) Filed Oct. 4, 1961, Ser. No. 142,846 16 Claims. (Cl. 115-40) My invention relates to water skiing, and more particularly to a practical water skiing propulsion apparatus.

Virtually all sustained water skiing is performed behind a tow boat and requires as a minimum a suitable boat, a high powered engine and a careful boat operator. Everyone realizes that the sport would be greatly simplified, and would grow in popularity if these tow auxiliaries could be dispensed with, at least after the skier is up on his skis, but there has been no practical means of doing this.

I am aware of suggestions in the prior art for self-propelled devices, but these cannot satisfy the need. Marin, Patent No. 2,509,630, as an example, suggests skiing with rockets which produce a vapor jet. This is impractical since it requires unduly large amounts of fuel and is therefore incapable of producing a sustained ride. Moreover, rockets are expensive, and their hand guiding as taught by Marin would make it difficult for the operator to ski in the conventional sense of moving his legs and body to guide him.

I have invented a practical means for self-propelled skiing which is economical and which can give a sustained ride to a water skier, thus solving the problem. I have actually used apparatus embodying the invention myself,

being skied upon by a Water pump, and to pump it rearwardly with sufficient force to overcome the drag upon the skier caused by the water intake as well as the normal resistance offered by the water surface and air, enabling him to ski successfully.

My invention, therefore, has as one principal objective, the utilization of this concept to provide a practical water ski propulsion apparatus.

Another principal objective is to provide such apparatus which incorporates a provision for buoyancy which both protects its drive unit and keeps the skier afloat when stopped.

Another objective of the invention is to provide air intake and exhaust passages for the drive unit disposed in such a relationship with the remainder of the unit as to permit their exposure to the atmosphere when the skier is stopped in water over his head, providing for running the unit in that position.

Another objective of the invention is to provide for the drive unit simple auxiliary apparatus for engine cooling and for protection against water from entering the exhaust or air-intake piping.

Another objective of the invention is to provide a drive unit in a compact, lightweight and inexpensive package suitable to be mass-produced.

Another objective of the invention is to provide for use with such a propulsion apparatus a highly efiicient water-intake arran ement which minimizes drag.

Another objective is to provide for use with such apparatus protection for the skier from being injured by his skis.

Yet another objective is to provide a water ski with integral water-intake means for use with such apparatus. This can provide stability while skiing and permit walking.

In the drawings:

FIG. 1 is a perspective view of a skier stopped in water over his head, showing a preferred embodiment of the propulsion apparatus in position;

FIG. 2 is a perspective view similar to FIG. 1 with a skier in a general attitude for successfully skiing.

FIG. 3 is a partially vertical cross-sectional and partially elevational view of the drive unit of the apparatus of the preceding figures looking towards the back of the skier;

FIG. 4 is a vertical cross-sectional view of the drive unit taken on line 4-4 of FIG. 3.

FIG. 5 is a horizontal cross-sectional view taken on line 5-5 of FIG. 3;

FIG. 6 is a top view of the unit of FIG. 3;

FIG. 7 is a side view of a portion of a ski and the water intake of the apparatus;

FIG. 8 is a view looking upwardly towards the bottom of an individual ski;

FIG. 9 is a vertical cross-sectional view taken on line 9-9 of FIG. 8 on an enlarged scale;

FIG. 10 is a vertical cross-sectional View taken on line 19-10 of FIG. 7;

FIG. 11 is a vertical cross-sectional view taken on line llll of FIG. 7; and

FIG. 12 is a perspective view of a control for the drive unit.

Referring to FIGS. 1 and 2, a water skier is shown with the apparatus. It comprises a drive unit 20 including a prime mover and a water pump having a water inlet. Water supply conduit here comprising flexible, noncollapsible tube 28 is connected to the unit and to a water-intake device 32 supported by a ski 30. The .unit has a rearwardly directed Water pump discharge port 34, here positioned directly adjacent the pressure side of the pump. Straps 36 are secured to the unit 20 and disposed firmly about the shoulders of the skier.

As Will be seen from FIGS. 36, in this preferred embodiment the prime mover is a two-cylinder reciprocating internal combustion engine 38 comprised of aluminum, having a hand-held control pendant 26, provision for air and exhaust and a drive shaft 40. The water pump comprises a centrifugal pump impeller 42 driven by shaft 46 and mounted in a pump casing 44, which communicates at the inlet 45 with water supply tube 28, and which communicates with the pump discharge port 34 at the pressure side. A flow divider 46 is employed to separate water being pumped through the port into two balanced streams. The pump impeller is balanced with respect to the engine and freely rotatable with said shaft, acting partially as the engine fly-wheel, thus saving in the weight of the unit.

A fuel tank 52 is mounted in the unit above the engine, and the starter means is adapted for actuation in a floating environment. One advantageous means is a wind-up starter spring, actuated by release of an escapernent. For simplicity of illustration the starter in the figures is shown as a cord 54 connected in a conventional way to the engine and extending out of the unit through a rubber bellows seal 55.

A small segment of the flow of water from the pressure side of the pump is directed through a cooling water inlet tubing 48 to the engine, around the cylinders thereof and is expelled through downwardly directed outlet 50.

A sealed drive unit housing 21 surrounds the engine, the pump and the tank, and defines a substantial volume preferably occupying about twice the space measured in cubic feet as the numerical value of the weight of the engine in pounds divided by 60, the latter being the approximate weight of water in pounds per cubic foot. In other words, the casing and contents displaces a greater weight of water than its own weight. In the excess space flotation material '56 such as lightweight expanded polystyrene foam is packed. Preferably, the forward side of the housing has a vertically curved surface 58 as shown in FIG. 4, shaped to conform to the shoulders and back of the skier to feel comfortable when the water outlet port 34 is positioned in horizontal alignment with his center of gravity. It is supported there by the straps 36 adapted for the purpose. While the port must be disposed to direct at least a major portion of the water rearwardly of the skier, a small downward component such as that through outlet 50 can serve to support the unit, taking its weight off the skier. Equally, the skier can lean backwards, thus directing the port slightly downwards, or the port can be directed slightly downwards relative to the housing, enabling the skier to stand upright while obtaining the same effect. A lateral component will apply a turning moment on the skier.

Air and.

exhaust pipe apertures

22 and 24 are located above the drive unit housing as indicated in FIGS. 3 and 4-. Air and exhaust isolation valves are provided at these for the purpose of preventing entry of water. An isolation valve actuator in the form of a flotation and impact actuatable element 60 pivots to release spring valves 61 which move in valve giudes 63 to tightly close the apertures in the event of a fall by the skier. To start and operate the motor, the valves are cocked open as shown in FIG. 4.

The drive unit as thus defined not only has sufficient buoyancy to support itself, but it aids in supporting the skier when he is stopped in the water, and together with the skis can position a crouched skier as in FIG. 1 with the trunk of his body generally vertical and the pipe apertures 22. and 24 exposed to the atmosphere. In this position the skier can pull the cord 54- and start the engine, and thereafter he can be brought to skiing position either by the apparatus alone or with the temporary aid of atowv.

The drive unit can displace approximately /2 to 1 cubic foot of water and weigh 15 to 30 pounds, depending upon the power and buoyancy requirements. In my experimental apparatus the unit including the housing weighed 24 pounds and displaced 30 pounds of fresh water, .48 cubic foot.

The engine -I employed in my experimental apparatus was a one cylinder, 2 cycle aluminum engine weighing 13% pounds and rated at 7 horsepower at 4500 r.p.m., manufactured by Tecumseh Products Company, Model AH82. Numerous other types of engines are suitable.

The water pump may be of any construction, e.g., turbine, centrifugal or gear type, which will discharge the required amount of water at a sufficient velocity to produce thrust to maintain forward motion. In my experimental apparatus, I employed a centrifu gm pump, with single suction overhung impeller which is satisfactory for this purpose. The impeller had a 3.656 inch diameter. It operated at speeds between 3000 and 4000 r.p.m., the same as the engine speeds, there being no need for a reduotion gear system between the engine and impeller, 21 very important advantage. During skiing the drive unit pumped as much as 46 c.f.rn. through the discharge port which had a cross-sectional area of 2.18 inch thus providing more than an adequate velocity head.

Referring to FIGS. 7-l-1, the preferred water-intake device 32 comprises on the bottom of at least one ski 30 at least one fin having at least one opening to admit water to its interior, but preferably, as shown, a pair of intake fins 62 disposed apart in catamaran fashion. Elongated intake slots 64 are disposed near the lower edges of these fins and communicate with the body of Water being skied upon. Preferably, at the front of each fin is an intake scoop 66. A pivoted valve member 63 having a smooth curved outer face is disposed to close the scoop opening and provide a streamlined aspect, and a weighted flap-type lever 70 which tends by its Weight to keep the opening open and the flap surface extending downwardly is connected to the valve and disposed in the water path between the fins for regulating the water flow as will be discussed herein. With suction applied to such intake openings, the ski acts as a cavitation plate, preventing entry into the intake of air bubbles which form as a result of high fiuid velocities and reduced pressure. This in turn prevents pump cavitation.

The interior of each fin communicates with a T manifold 72 at the lower end of the water supply tube 28, secured to riser 73 on the ski at the joint 74 shown in FIG. 11. Preferably, a foot valve 75- is disposed in each leg of the T which prevents loss of prime in the event one or both skis is temporarily raised out of the water as during a jump or other maneuver. However, even without this valve, loss of prime would only be temporary, since the forward velocity of the skier would immediately force water to the pump when re-entering the water.

Referring particularly to FIGS. 7 and 9, a safety hold ing device is preferably provided to permit separation of the skier from his ski in the event of a fall. This preferably includes a catch 76 engaged with a suitable tube abutment, the latter being directed away from the end of the tube 28. A pivoted heel plate 77 is linked to the catch so that the plate when pressed down causes the catch 76 to move towards the tube and engage the abutmerit thus restraining the end portion of the tube from leaving the riser. A spring 78 is adapted to urge the catch outwardly from the tube, which automatically releases the catch when the heel pressure on plate 77 is released to permit removal of the tube from the riser. In norm-a1 operation the foot is inserted in the slipper binding 80, and the heel normally bears upon the plate 77. The bottom of each fin has a substantial horizontal extent in the direction of the ski axis adapted to permit walking with the skis. At spaced-apart points antifriction means are preferably installed, here partially exposed, rotatable spherical balls 90 to permit sliding movement relative to hard surfaces.

Referring to FIG. 12, at the hand end of the power control pendant 26 is a hand-carried console 80 with suitable means for controlling the throttle, the choke and the ignition switch S2, 84 and 86 respectively.

To commence operation, the skier may walk into the water on the spaced-apart fins. When he gets into sulficiently deep water, he lowers himself allowing the skis and the drive unit to buoy him. The isolation valve control 60 is cocked in the open position, the control console is set and the engine is started. The pump draws water through the tubing 28 from the fins and forces it out through the discharge port 34. The skier uses his body motions to direct the stream of water enabling him to maneuver in the water. As soon as smooth operation of the engine is obtained, and he is in the position of FIG. 1, the skier opens up the engine full throttle. From here he may be assisted to skiing position by the temporary use of a tow boat, or he can rely on his engine alone.

The effect of the discharged water from the power unit is to force the skier forward, overcoming the restraining forces and his inertia. With the skis disposed with tips sloped upwardly as shown in FIG. 1, the thrust and the skis tend to bring him to the surface.

As soon as the skier commences skiing, he is able to use his legs and body to guide his skis and the pump outlet in a technique more similar to snow skiing than that employed in conventional water skiing. With the elimination of the tow rope and the constant pull from an extended distance and with the lateral stability afforded by the fins, he is free to make much sharper turns. The bottoms of the fins of the skis equipped as shown or with skids or antifriction material such as fluorocarbon plastics enable him to negotiate jumps.

In the water intake device during operation, the scoop openings 66 create a velocity head which fills the fin and tube under pressure greater than atmospheric. Thus the operation does not depend entirely on vacuum drawing up of the water, and the skier can negotiate a jump out of the water without permanently losing power. With increase in speed the weight of the scoop valve control 70 is partially overcome by the force of the water. It pivots rearwardly tending to align with the flow of water between the fins, and this closes the water scoop 66 at least partially, thereby serving as a speed responsive control automatically regulating the supply of the water, which otherwise could increase too rapidly and increase drag as speed increases. With the valve in closing position, the leading edge of the fin is streamlined. When the scoop is not employed, all water enters through slots 64.

The water inlet fins give lateral stability similar to that of a center board in a boat, and through a possible catamaran effect they may reduce drag.

At the end of a run, or whenever the skier loses his balance and falls, the valves at the air and exhaust pipe apertures automatically close, stopping the engine, and with release of heel pressure, the catch 76 disengages the tubes 28. These slip free from risers 73 thus separating the skier from his skis, which avoids dragging the ski which might strike the skier.

It will be seen that -I have provided apparatus which is lightweight and simple to manufacture, which eliminates the need for a tow boat during skiing and is safe for water skiing when alone. Such factors as body guiding, increase in maneuverability and dispensing with constant pull on the arms make water skiing with my device more enjoyable and thrilling than conventional skiing.

Numerous modifications can be made in certain specific details of the invention within its spirit and scope.

What is claimed is: 1. A water ski propulsion apparatus comprising a water-intake means adapted to be supported by at least one ski, a lightweight prime mover, a water pump actuated by said prime mover, means for mounting said prime mover and pump on the back of a skier, said pump having a water inlet, a flexible, noncollapsible conduit for conducting Water =fiom said intake means to said inlet,

and a water discharge port in communication with the pressure side of said pump adapted to direct water rearwardly of said skier.

2. The apparatus of claim 1 wherein said prime mover is an internal combustion engine.

3. The apparatus of claim 2 wherein said prime mover and pump are enclosed in a housing capable of displacing a volume of water weighing in excess of the weight of the housing and its contents, the volume of said housing not occupied by said prime mover and pump being hermetically sealed, adapted to provide buoyancy.

4. The apparatus of claim 1 wherein said water-intake means comprises at least one fin mounted on the bottom of a ski and extending downwardly therefrom, said fin having at least one opening for receiving water from the body of water being skied upon, and having passage means connecting the interior of said flexible, noncollapsible fin to said conduit.

5. The apparatus of claim 4 wherein said water-intake means comprises a pair of downwardly extending fins mounted on the bottom of said ski, said fins being spaced apart to permit water to pass therebetween, and having openings through which water may enter to proceed through said passage to said flexible, noncollapsible conduit.

6. The apparatus of claim 5 wherein said fins are shaped to provide a stable support for walking on land.

7. The apparatus of claim 4 wherein said conduit is a flexible tube separable from said water intake means and is connected thereto by a releasable device comprising a holding means adapted to hold said tube against upward movement relative to said ski, a lever heel plate mounted on said ski adapted when pushed against said ski by the heel of a skier to force said holding means to engage said tube, said holding means being adapted to release said tube on release of pressure by said heel to permit removal of said tube with respect to said intake means in the event of a fall.

8. The apparatus of claim 4 wherein said opening is in the front of the ski defining a water scoop adapted to provide a velocity head at said opening and within said conduit during skiing.

9. The apparatus of claim4 wherein said aperture is at least one elongated slot in the side of said fin near its lower edge.

10. The apparatus of claim 3 including air-inlet and exhaust passages extending upwardly from said engine to apertures, strap means mounted on said housing adapted to be secured to said skier and buoy him while simultaneously holding said air and exhaust apertures above the water surface.

=11. The apparatus of claim 10 wherein isolation valve means is provided for said air-inlet and exhaust apertures, and actuator means is provided in combination with said valve means, adapted to respond to floating effect of water and to impact, to close said valve to pre vent entry of water into said engine.

12. A drive unit for a water ski propulsion apparatus comprising a housing having a forward surface shaped to rest upon the back of a skier, a lightweight, reciprocating, internal combustion engine in said housing, a water pump in said housing comprising an enclosing casing and an impeller adapted to be actuated by said engine, means for connecting inlet water tubing to said pump, a

water discharge port for directing water from said pump rearwardly for driving said skier forward, a fuel tank mounted adjacent said engine on said housing, flotation material in said housing around said engine, and air-inlet and exhaust piping extending upwardly from said engine above said housing.

13. The drive unit of clairn 12 wherein said discharge port is provided in the rear surface of said housing, and said housing has shoulder straps mounted and adapted to support said housing relative to said skier positioning said port substantially in horizontal alignment with the center of gravity of said skier.

14. The apparatus of claim 2 wherein flotation material surrounds the internal combustion engine in a quantity sufiicient to float said engine and said pump.

15. A ski adapted for use with a prime mover-water pump combination, said ski having a foot binding, at least one downwardly extending hollow member, at least one opening in said hollow member for communicating with the body of water being skied upon, a passage defined upwardly from said hollow member through the ski to an outlet located intermediate the ends of the ski, adjacent said foot binding, said outlet positioned to furnish water for a pump on the back of a skier and means for connecting a flexible tube in communication with said outlet, said opening being disposed in the forward end of said hollow member as a water scoop and a valve disposed within said hollow member, adapted to at least partially close said opening and present an outwardly disposed strearnlined surface to decrease drag on said ski as it moves through the water, a valve actuator extending outside said hollow member into the body of water, adapted to be actuated by the movement of water relative to said ski to at least partially close said valve.

16. A ski adapted for use with a prime mover-water pump combination, said ski having a foot binding, at least one downwardly extending hollow member, at least one opening in said hollow member for communicating with the body of water being skied upon, a passage defined upwardly from said hollow member through the ski to an outlet located intermediate the ends of the ski, adjacent said foot binding, said outlet positioned to furnish water for a pump on the back of a skier and means for connecting a flexible tube in communication with said outlet, said flexible tube being separable from said ski, and said means for connecting said flexible tube in communication with said outlet comprising a releasable holding means adapted to hold said tube in connection with said outlet by pressure of a foot in position on said ski, and adapted to release said tube on loosening movement of said foot relative to said ski.

1,607,244 Diller Nov. 16, 1926 Marin May Steele Apr.

Fifer June McKinney July Tierney Feb. Kincaid Mar.

FOREIGN PATENTS Germany Oct.

Claims

1. A WATER SKI PROPULSION APPARATUS COMPRISING A WATER-INTAKE MEANS ADAPTED TO BE SUPPORTED BY AT LEAST ONE SKI, A LIGHTWEIGHT PRIME MOVER, A WATER PUMP ACTUATED BY SAID PRIME MOVER, MEANS FOR MOUNTING SAID PRIME MOVER AND PUMP ON THE BACK OF A SKIER, SAID PUMP HAVING A WATER INLET, A FLEXIBLE, NONCOLLAPSIBLE CONDUIT FOR CONDUCTING WATER FROM SAID INTAKE MEANS TO SAID INLET, AND A WATER DISCHARGE PORT IN COMMUNICATION WITH THE PRESSURE SIDE OF SAID PUMP ADAPTED TO DIRECT WATER REARWARDLY OF SAID SKIER.