|Publication number||US3015830 A|
|Publication date||Jan 9, 1962|
|Filing date||Jan 25, 1960|
|Priority date||Jan 25, 1960|
|Publication number||US 3015830 A, US 3015830A, US-A-3015830, US3015830 A, US3015830A|
|Inventors||Clark Frederick L|
|Original Assignee||Canadian Res & Dev Foundation|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (4), Referenced by (7), Classifications (6)|
|External Links: USPTO, USPTO Assignment, Espacenet|
Jan. 9, 1962 F. CLARK WATER SKIS Filed Jar 25,-1960 INENTOR 3,015,830 WATER SKIS Frederick L. Clark, Canadian Research Development Foundation, 1434 Queen St., West Toronto :3,
Ontario, Canada Filed Jan. 25, 1960, Ser. No. 4,443
This invention relates to water skis and more particularly to water skis of buoyant type adapted to be used for both water walking and high speed skiing purposes.
Various types of buoyant water skis have previously been utilized, such water skis however on account of their considerable bulk creating a-considerable drag on the water as the skier is pulled thereover, requiring comparatively powerful motors for towing. 7
Another disadvantage in the conventional types of water skis lies in the necessity to provide adjustable footholds in order to fit such foot-holds to various sizes of feet.
It is an object of this invention to provide water skis of suflicient buoyancy to completely support the weight of a skier.
It is another object of this invention to provide water skis particularly adaptable to high speed skiing, in that they offer reduced friction surface between ski and water as speed is increased.
It is a further object of this invention to provide water skis supplied with channels or grooves in the nether surface of the skis, adapted to draw in a flow of air beneath the skis, thereby providing a partial air cushion beneath the skis, between the skis and the surface of the water, giving the advantage of lower friction during high speed.
It is a further object of this invention to provide skis that through longitudinal grooving in the lower surface of the skis provides better directional stability of the skis, and less danger of inadvertently side slipping on the surface of the water during high speed towing.
It is another object of this invention to providewater skis containing automatic flap means at the rear end of the skis, adapted to be used during water walking, such flaps on the two skis alternately creating resistance against back slip, while the ski on the opposing foot is thrust forward through the water.
These and other objects and features of this invention will become apparent when taken in conjunction with the following drawings in which:
FIG. 1 is a perspective view of water skis embodying this invention, shown being utilized by a skier for water walking purposes.
FIG. 2 is a top plan view of a water ski shown in FIG. 1.
FIG. 3 is a side elevation of the'water ski shown in FIG. 2 illustrating the flap attachment utilized for water walking.
FIG. 4 is a reverse plan view of the water ski illustrated in FIG. 2 showing one method of locating fluted channels or grooves therein.
FIG. 5 is a cross-sectional view of the water ski shown in FIG. 3 illustrating particularly the self-adjusting foothold.
FIG. 6 is a cross-sectional view of the water ski shown in FIG. 3 illustrating particularly a preferred configura forcement purposes, a foot well 5 being located within the upper surface of each water ski substantially centrally and longitudinally of the top surface of each water ski 1 and 2, flexible se1f-adjusting shoes being located within each well 5.
A collapsible flap 7, hingeably located substantially towards the rear end 8 of each water ski, is shown on water ski l1, flap 7 being limited in its forward pivotable movement to a maximum angle of 90 degrees with the longitudinal axis of water ski '1, flap 7 being adapted to be pivotably rotated backward to a horizontal position.
Referring to FIG. 2, FIG. 3 and FIG. 4 a water ski embodying this invention is shown comprisinga hollow buoyant hull 9 having reinforcementflutes 10 located in upper surface of hullv 9 and foot well 11 containing flexible self-adjusting shoe 12. Fluted grooves 13 located in lower surfaceof hull 9, parallel to longitudinal axis of hull 9, are adapted to provide reduction of surface for friction against water during high speed skiing, and at the same time are adapted to permit air to enter grooves 13, as ski is moved forward, thereby providing a partial air cushion between the hull 9 and surface of the water in order to cut down on surface friction. I
A hingeably attached flap 14 is located transversely of the longitudinal axis of hull 9, substantially toward the rear end 15- of hull 9.
Referring to FIG. 5 a cross-section illustrating the relation between hull 9 and flexible self-adjusting shoe 12, located in well 11, is shown, the bottom surface of well 11 being concave as at 16, the lower surface 17 of shoe 12 being flat in its unstressed position.
Upon a foot being inserted into shoe '12, the heel and ball of the foot resting on sole 18 will force centre portion of sole 18 down into concave base of well 11 thereby causing sides 19 of shoe 12 to flex inwards towards the foot of the skier thereby adapting itself to the sides of the foot independently of whether this be somewhat smaller than the size of the shoe.
Upon the skier Wishing to free himself from the shoe, he requires only to retract his foot from the shoe, whereby pressure acting on sole 1 8 is relieved, permitting sides 19 to flex outwards and thereby free the foot automatically.
Referring to FIG. 6 a section through the hull 9 of the water ski is shown illustrating one way of locating flutes 13 in base of hull 9, the high speed friction surface, during high speed skiing, being reduced to the flat surfaces 20.
Referring to FIG. 7, arrangement of the hingeable flap 14 toward the end 15 of hull 9 is shown, flap 14 being adapted to move hingeably towards the rear, to a substantially horizontal position as shown by stipled line 21, whereas flap 14 is restricted in its forward movement, through stop portion 22 acting on end 23 on flap 14.
It will be appreciated that air trapped within flutes 13, during high speed forward motion of water skis, will have a directional action somewhat similar to a protruding keel, thereby tending to stabilize the motion of the water skis, at the same time providing lower friction, since friction at the flutes will be between the hull and air, instead of the hull and water.
It will also be understood that any quantity of flutes may be located in the lower surface of each ski, according to the size of the ski and the weight that each ski must support. Skis-may be made in varying sizes according to the weight of the skier, and the general design of the skis embodying this invention may be varied within the scope of this invention without prejudicing the novelty thereof.
The flexible self-adjusting shoe shown in FIG. 5 may be removably attached within well 111 through bead-like projections 24 engaging in grooves 25 located around the lower end of well 111, and ventilating means 26 may be Patentedv Jan. 9, 1962 supplied in base portion 1-8 of shoe 12, to ventilate concave portion 16 of well 11 during flexing of base 18.
The embodiments of the invention in which an exclusive property and privilege is claimed are defined as follows.
1. A pair of identical water skis, each of said pair of water skis comprising a buoyant hull of substantially longitudinal pontoon-shaped configuration, a foot well located within the upper surface of said hull substantially centrally of the longitudinal axis of said hull, the bottom of said foot well being substantially concave and foot hold means removably located within said foot well, said foot hold means having the configuration of a loose fitting shoe having a flexible sole portion, the central longitudinal portion of said sole portion being adapted to flex downwards into said concave base of said foot well upon a foot being applied to said sole portion, said foothold means having flexible sides adapted to flex towards a foot located in said foot hold means upon a foot biasing said sole portion into said concave bottom of said foot well.
2. A pair of water skis as claimed in claim 1 in which said sole of said foot hold means is adapted to be sufiiciently elastic to automatically bias said sole toward a substantially flat plane upon said sole being released from weight of said foot, said sides of said foot hold means thereby being adapted to release grip on said foot to permit extraction thereof from said foot hold means.
3. A pair of water shoes as claimed in claim 1 in which said flexible sole of said foot hold means is supplied with ventilating means between the lower and upper surface of said sole.
References Cited in the file of this patent UNITED STATES PATENTS 1,714,352 Echola' May 21, 1929 1,719,059 Krupka July 2, 1929 2,020,792 Maynard NOV. 12, 1935 FOREIGN PATENTS 38,685 Germany Feb. 23, 1 887
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US1714352 *||Oct 17, 1927||May 21, 1929||Echola Arnold H||Water ski|
|US1719059 *||May 31, 1928||Jul 2, 1929||Colestin Krupka||Water glide shoe|
|US2020792 *||Sep 5, 1934||Nov 12, 1935||Alton Maynard Ernest||Water craft|
|DE38685C *||Title not available|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US3097376 *||Jul 5, 1961||Jul 16, 1963||forsman|
|US3178738 *||Nov 16, 1961||Apr 20, 1965||Everett A Brunner||Convertible swim fin|
|US3227125 *||Mar 14, 1963||Jan 4, 1966||Grebe John J||Propulsion unit and craft for use therewith|
|US5421759 *||Feb 2, 1994||Jun 6, 1995||Morin; Robert||Dynamically balanced bouyant skis|
|US5593334 *||Aug 9, 1995||Jan 14, 1997||Thayer; Thomas E.||Water walkers|
|US5616060 *||Nov 23, 1993||Apr 1, 1997||Morin; Robert||Leg support for aquatic skis|
|DE2931210A1 *||Aug 1, 1979||Feb 19, 1981||August Nollert||Water ski made as hollow body - has bottom surface shaped like normal ski and ski binding is located on floor of recess|
|U.S. Classification||441/76, D21/766|
|International Classification||B63B35/83, B63B35/73|