US3747947A - Ski with adjustable device - Google Patents

Abstract

Application of an adjustable device to skis, which influences the skiing qualities by the variation of the mass moment of inertia.

Description

United States Patent [1 1 Gunzel [451 July 24, 1973 1 SKI WITH ADJUSTABLE DEVICE [76] Inventor: Ernst Werner Gunzel,

Waldperjacher Str. 12, D-8000 Munich 83, Germany [22] Filed: Oct. 21, 1971 [21] Appl. No.: 191,236

[30] Foreign Application Priority Data 3,439,928 3/1969 Noguchi 280/1 1.13 K

FOREIGN PATENTS ORHAPPLICATIONS 1,428,873 12/1968 Germany 280/1l.13 F 1,428,966 1/1969 Germany 280/11.l3 F

1,478,110 9/1969 Germany 280/11.l3 F

Primary ExaminerLeo Friaglia Assistant Examiner-David M. Mitchell Attorney-Woodhams, Blanchard and Flynn [57] ABSTRACT Application of an adjustable device to skis, which influences the skiing qualities by the variation of the mass moment of inertia.

7 Claims, 7 Drawing Figures SKI WITH ADJUSTABLE DEVICE BACKGROUND OF THE INVENTION Skis with adjustable devices are known from the German Offenlegungsschriften (German patent application laid open to public inspection) 14 28 966 and I4 28 941. These Offenlegungsschriften especially describe adjustable devices which change the stiffness of the ski, which is understood as the product composed out of the modulus of elasticity multiplied by the area moment of inertia, or which change the elasticity of the ski in order to gain different gliding qualities. Furthermore details are submitted to obtain by means of elastic elements a uniform pressure and moment distribution on the gliding surface of the ski.

Moreover new structural designs of skis are commonly known today which utilize to a considerable extent filament materials combined with resins. Using these materials results in a considerable weight saving and moreover offers the possibility to influence the long'itudinal-, lateral-, and torsional stiffness characteristic along the total ski in such a mode to gain distinguished gliding qualities. Since today an extreme high torsional stiffness is preferred new designs of skis apply a box type construction form which delivers a completely closed torsional tube with maximum torsional stiffness. On account of these modern structural designs it.is possible to form the ski body hollow.

The purpose of the invention is to accomplish a new ski with an adjustable device which offers the possibility to combine the stability qualities of a long and a short ski and all interim sizes by choice without changing the external dimensions of the ski and only by utilizing the adjustable device. This peculiarity is solved according to the invention with a ski of the above mentioned characteristic by at least one movable mass which can be displaced in longitudinal direction of the ski by means of the adjustable device and which changes the mass moment of inertia about the vertical axis of the ski.

The invention provides, that, outside or inside of the ski masses can be arranged in a fixed movable position. The mass moment of inertia can be changed considerably by changing the position of the masses either by fixing or shifting them to different places in longitudinal direction of the ski. Therefore it is possible to incorporate in only one ski the mass moments of inertia of short and long skis with all interim moments and to gain stability and gliding qualities which have not been known up to now. According to privileged construction versions of the invention, only one or more, but espe cially two masses can be fixed at distinct places of the ski in an initial position from which they can be transferred to another fixed position or they can be shifted for instance continuously by means of a cable device in longitudinal direction of the ski and can be locked with the same device at an attained position simultaneously.

The principles of the invention-are explained by an example design illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 3 is the same ski form as above but with another position of the masses shown in FIG. 1 and FIG. 2;

FIG. 4 is a more detailed presentation of the adjustable device shown in a cross section view;

FIG. 5 is a view from above of the adjustable device shown in FIG. 4;

FIG. 6 is a cross section view of the end of the ski;

FIG. 7 is a cross section view from above of the end of the ski shown in FIG. 6.

DESCRIPTION OF THE EMBODIMENTS Referring first to FIGS. 1, 2 and 3 the schematical arrangement, in a view from the sideand two top views, illustrates a hollow ski 5 in a box type construction which contains two continuously movable masses 1. By operating the adjustable device 2 the masses 1 can be moved towards the center or to the ends of the ski 5 by means of a cable 3 and two guide pulleys 4 in such a manner, that they can be locked at all interim positions between the extreme outer position illustrated in FIGS. 1 and 2 and the extreme inner position illustrated in FIG. 3. The position of a conventional ski binding is 'indicated by the reference number 6.

Further details of the arrangement are shown in the FIGS. 4, 5, 6 and 7 presented in two side views in cross section and two views from above one of which is also presented in a cross section view. The movable masses 1 consisting of a material of high specific gravity are presented in form of a plate which may consist out of one piece, or, on account of the bending of the ski during skiing, of elements which are combined together flexible. The adjustable device 2 is schematically presented by a cable pulley 21 and control disc 22 which is positioned above the ski 5 near the center. The masses 1 can be moved inside the ski body 51 within certain limits by the cable 3 which is guided around the two guide pulleys 4 and which can be moved'by operating the adjustable device 2.

In FIGS. 6 and 7 a mass 1 is visible in an extreme closed position to the guide pulley 4' in the end part of the ski. The guide pulley 4 and the mass 1 are partly covered by the cable 3 in FIG. 6.

What is claimed is:

1. In a ski having an elongated body, the improvement comprising:

mass means means mounted on said body for selectively moving said mass means in a direction generally parallel to the longitudinal axis of said body, said mass means in one longitudinal position on said body defining one stability and gliding characteristic, said mass means in another longitudinal position on said body defining another stability and gliding characteristic.

2. The improvement according to claim 1, wherein said mass means comprises a pair of masses both mounted for longitudinal movement on said body toward and away from each other and the center of said body.

3. The improvement according to Claim 2, wherein said means for moving saidmasses comprises cable means guided by pulley means and drive means for driving said cable means relative to said body, said masses being secured to a reach of said cable means and being movable by said cable means along said body when said cable means is driven by said drive means.

7. The improvement according to Claim 6, wherein said moving means comprises cable means guided by pulley means and drive means for driving said cable means relative to said body, said mass means being secured to a reach of said cable means and being movable by said cable means along said body when said cable means is driven by said drive means.

Claims (7)

1. In a ski having an elongated body, the improvement comprising: mass means means mounted on said body for selectively moving said mass means in a direction generally parallel to the longitudinal axis of said body, said mass means in one longitudinal position on said body defining one stability and gliding characteristic, said mass means in another longitudinal position on said body defining another stability and gliding characteristic.

2. The improvement according to claim 1, wherein said mass means comprises a pair of masses both mounted for longitudinal movement on said body toward and away from each other and the center of said body.

3. The improvement according to Claim 2, wherein said means for moving said masses comprises cable means guided by pulley means and drive means for driving said cable means relative to said body, said masses being secured to a reach of said cable means and being movable by said cable means along said body when said cable means is driven by said drive means.

4. The improvement according to Claim 3, wherein said body is hollow and said masses are mounted for movement inside said body.

5. The improvement according to Claim 1, wherein said elongated body is hollow and said movable mass is mounted for movement inside said body.

6. The improvement according to Claim 1, wherein said mass means comprises a mass movable longitudinally of said body.

7. The improvement according to Claim 6, wherein said moving means comprises cable means guided by pulley means and drive means for driving said cable means relative to said body, said mass means being secured to a reach of said cable means and being movable by said cable means along said body when said cable means is driven by said drive means.

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