US3918114A

US3918114A - Water skis

Info

Publication number: US3918114A
Application number: US471861A
Authority: US
Inventors: Bruno Schmitt
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-11-07
Filing date: 1974-05-21
Publication date: 1975-11-11
Anticipated expiration: 1992-11-11
Also published as: FR2249687A1; FR2249687B1

Abstract

A water ski having enhanced stability when compared to the prior art results from the formation, at the sole of the ski, of a plurality of grooves which extend inwardly from each end a portion of the length of the ski. The grooves are angled with respect to the main axis of the ski so as to deflect water passing under the trailing end of the ski toward the trajectory axis of the skier.

Description

United States Patent [191 Schmitt Nov. 11, 1975 1 WATER SKIS [76] Inventor: Bruno Schmitt, 91 rue de llndustrie, 38170 Seyssinet-Pariset, France [22] Filed: May 21, 1974 [21] Appl. No.: 471,861

[30] Foreign Application Priority Data Nov. 7, 1973 France 73.39500 [52] US. Cl 9/310 R; 280/1 1.13 S [51] Int. Cl. A63C 5/04 [58] Field of Search 9/310 R, 310 A, 310 AA,

9/310 E; 280/11.13 S; D34/40, 14 D; 114/665 R, 56, 63

[56] References Cited UNTTED STATES PATENTS 3,118,157 l/1964 Houser 9/310 AA gasses.

8/1968 Pope et a1 9/310 A 2/1969 Johnson 280/1 1.13 5

OTHER PUBLICATIONS Taper-F lite, Nash Manufacturing, Inc., Fort Worth, Tx., Mar. 1968.

Primary Examiner-Trygve M. Blix Assistant E.\aminerEdward R. Kazenske [5 7] ABSTRACT A water ski having enhanced stability when compared to the prior art results from the formation, at the sole of the ski, of a plurality of grooves which extend inwardly from each end a portion of the length of the ski. The grooves are angled with respect to the main axis of the ski so as to deflect water passing under the trailing end of the ski toward the trajectory axis of the skier.

4 Claims, 2 Drawing Figures US. Patent Nov. 11, 1975 WATER SKIS 1 BACKGROUND or THE INVENTION 1. Field of the Invention 1 a The present invention relates to water skis. More particularly, this invention is directed to improving the stability of water skis employed in competition. Accordingly, the general objects of the present invention are to provide novel and improved apparatus and methods of such character.

2. Description of the Prior Art In international water ski competition the participants are required to perform a number of maneuvers when they are both facing and have their backs to the tow boat. The ability to and necessity of skiing backwardly dictates that the skis be symmetrical with respect to a plane perpendicular to their main axis. Such symmetrical skis are known in the art.

While previously available water skis have numerous attributes, there is a long standing desire in the art for improvements in the stability of the skis.

SUMMARY OF THE INVENTION The present invention comprises a novel and improved water ski design which is characterized by enhanced stability when compared to the prior art. In accordance with the invention the bottom surface of each ski is provided with a number of grooves. These grooves preferably extend inwardly from both ends of the ski'along a portion of the length of the ski only- Also the grooves define notches preferably oriented in such a manner as to deflect the water passing under the ski toward the trajectory axis of the skier. This desired deflection is accomplished by use of grooves which converge, toward the respective ends of the ski, toward the main axis of the ski. Thus, in a'preferred embodiment, the grooves formed on the bottom of the ski converge toward the outside of the main axis of the ski.

BRIEF DESCRIPTION OF THE DRAWING The present invention may be better understood and its numerous objects and advantages will become apparent to those skilled in the art by reference to the accompanying drawing wherein:

FIG. 1 is a bottom plan view of a water ski in accordance with the present invention; and

FIG. 2 is a cross-sectional side elevation view of the ski of FIG. 1 taken along line B-B of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT With reference now to the drawing, and particularly to FIG. 1, for purposes of explanation it.will be presumed that the end of the ski, indicated generally at 10, indicated A is the normally leading or forward facing end whereas the end indicated A is normally the trailing edge of the ski. Thus, as the skier is pulled he will normally advance in the direction A'A and the end A of the ski will be in the water while the end A will have a tendency to lift itself out of the water. Of course, when the skier does a 180 revolution, the ski will move through the water in the direction AA and-end A will be immersed while end A will be slightly out of'the water.

In the disclosed embodiment the ski has been provided with six grooves at each end; the grooves at the ends A and A respectively being indicated by

reference numerals

12,14, 16,18, 20, 22 and 12, 14, 16, 18, 20, 22. These grooves converge toward the respective ends of the ski; i.e., respectivelyin the directions'A and A; and also toward the main axis of the ski which is indicated by a broken line. 'It is to be understood that, while six grooves appear for most skis to offer the optimum performance improvement, it is possible to use more or less than six grooves and the grooves may be larger or smaller, longer or shorter or shallower or deeper than shown in the accompanying drawing without departing from the spirit and scope of the invention. Additionally, while optimum performance is obtained by the use of grooves which are angled with respect to the main axis of the ski, it is also possible to employ parallel grooves.

Movement of the ski through the water creates a plurality of streams which, in the disclosed embodiment, converge toward the main axis of the ski at the end which is in the water. The grooves at the other side of the ski; i.e., at the leading end which is normally raised above the surface of the water; have practically no effect on the performance of the ski.

In the preceding discussionis was presumed that the ski was operating on a surface that was relatively smooth. In the case of a body of water with a rough surface the trailing edge of the ski will periodically leave the water. These short time duration losses of the stabilizing effect of the grooves of the present invention have been found not to detract from the overall improved performance of a ski in accordance with the present invention.

As shown in FIG. 2, the desirable stabilization enhancement. of the present invention is preferably achieved by the formation of grooves in the sole 24 of the ski. The grooves could also be defined by attaching half-round staves in any suitable manner to the sole of the ski. It has, however, been found that protruding parts such as staves produce, at the leading edge of the ski, eddies which produce a braking effect. Accordingly, the arrangement of FIG. 2 is preferred.

While a preferred embodiment has been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is' to be understood that the present invention has been described by way of illustration and not limitation.

What is claimed is:

1. In water ski, the ski comprising an elongated body having an upper foot supporting side and an oppositely disposed base and normally leading and trailing edges, the improvement comprising:

a first plurality of grooves in the base of the ski, said grooves extending inwardly from the normally trailing edge of the'ski at an oblique angle with respect to the longitudinal axis of the ski in such a manner as to deflect water passing therethrough toward the trajectory of the ski, said grooves terminating intermediate the length of the ski.

2. The ski of claim 1 wherein said grooves converge toward the longitudinal axis of the ski and toward the normally trailing edge.

3. The ski of claim 1 further comprising:

a second plurality of grooves in the base of the ski,

said grooves of said second plurality extending inwardly from the normally leading edge of the ski at an oblique angle with respect to the longitudinal axis of the ski, the grooves of said second plurality t 4 I 4. The ski of claim-3 wherein said grooves of said first and second pluralities are convergent toward the longitudinal axis of the ski and respectively toward the nor edges of the ski.

mally trailing and leading

Claims

1. In water ski, the ski comprising an elongated body having an upper foot supporting side and an oppositely disposed base and normally leading and trailing edges, the improvement comprising: a first plurality of grooves in the base of the ski, said grooves extending inwardly from the normally trailing edge of the ski at an oblique angle with respect to the longitudinal axis of the ski in such a manner as to deflect water passing therethrough toward the trajectory of the ski, said grooves terminating intermediate the length of the ski.

3. The ski of claim 1 further comprising: a second plurality of grooves in the base of the ski, said grooves of said second plurality extending inwardly from the normally leading edge of the ski at an oblique angle with respect to the longitudinal axis of the ski, the grooves of said second plurality terminating intermediate the length of the ski and short of the inner termination of the grooves of said first plurality, water passing through the grooves adjacent the instantaneously trailing edge of the ski being deflected toward the trajectory of the ski.

4. The ski of claim 3 wherein said grooves of said first and second pluralities are convergent toward the longitudinal axis of the ski and respectively toward the normally traiLing and leading edges of the ski.