FLEXIBLE STRUCTURE FOR SKI TRACKS AND THE LIKE
United States Patent 3809391
A flexible structure for ski tracks for simulating skiing on snow. The flexible structure comprises similar partially imbricated elements. Each element is made of a succession of upstanding parallel arcs. The tops of the arcs are provided with protuberances and vertically protruding flexible fingers. The base basis of the fingers are at a level lower than top of the protuberances.
US Patent References:
PLASTIC SKI TRACK
Del Piano et al. - May 1969 - 3443493
ELASTIC SOFT STRUCTURE, AND ITS APPLICATION TO THE MAKING OF SPORTING TRACKS AND RUNS
See - January 1971 - 3557668
/3574107.html
Hurka - April 1971 - 3574107
PLASTIC SKI TRACK
Del Piano et al. - May 1969 - 3443493
ELASTIC SOFT STRUCTURE, AND ITS APPLICATION TO THE MAKING OF SPORTING TRACKS AND RUNS
See - January 1971 - 3557668
/3574107.html
Hurka - April 1971 - 3574107
Application Number:
05/351888
Publication Date:
05/07/1974
Filing Date:
04/17/1973
View Patent Images:
Export Citation:
Assignee:
Royalty S.A. (Luxemburg Grand Duchy, LU)
Primary Class:
International Classes:
E01C13/12; E01C13/00; A63B69/18; A63C19/10
Field of Search:
272/56.5R,56.5SS,57B 273/195R,195A,195B,176H,176J,DIG.13 15/238,239 404/17,71,35
Primary Examiner:
Oechsle, Anton O.
Assistant Examiner:
Kramer, Arnold W.
Attorney, Agent or Firm:
Imirie, And Smiley
Claims:
1. A flexible structure for ski tracks comprising various similar elements, each element having a base cross-piece connecting upstanding parallel and substantially filiform arcs, said elements and arcs being partially imbricated together to form said structure and each side of each arc adjacent the top thereof provided with a number of enlarged protuberances, said protuberances being separated by upstanding flexible fingers on said arc with the fingers on each arc lying in the plane of the respective arc and the base of each said finger being at a level lower than the tops of
2. The structure as set forth in claim 1, wherein the arcs are each delimited at the median portion thereof of a V-shaped part whereby the V-shaped part of successive arcs of an element delimit a slot similar to a groove delimited by the overlapping arcs of two contiguous imbricated
3. The structure as set forth in claim 2, wherein the arcs and the V-shaped parts provided in the median portion thereof have a size and shape depending upon the usual width of a ski whereby said ski width covers at
4. The structure as set forth in claim 1, wherein the upstanding fingers are cone-shaped with the tops thereof extending in a same horizontal plane, said fingers having substantially identical apex angles, the bases of said fingers, at levels where joined to said arcs, each having a correspondingly varied diameter depending on the height of the respective fingers to substantially equalize the bending strength of said fingers.
5. The structure as set forth in claim 1, wherein two adjacent protruding fingers of a same arc are separated by an interval which is substantially equal to the smallest interval separating two imbricated contiguous arcs, whereby the number of fingers is substantially constant per unit of surface in all directions of a sheet constituted by said imbricated
6. The structure as set forth in claim 1, wherein the enlarged protuberances are ball shaped and protrude above the filiform of the arcs to constitute bearing surfaces for a ski upon considerable bending over of
7. The structure as set forth in claim 1, wherein lateral fingers protrude from each side of each arc, the lateral fingers on one half side protruding rearwardly and the lateral fingers on the other half side protruding forwardly, said lateral fingers being upwardly bent substantially following the bend of the arc supporting the same, whereby they constitute locks when the arcs of two contiguous elements are
8. The structure as set forth in claim 7, wherein struts are further
9. The structure as set forth in claim 8, wherein said struts connect said arcs just above the lateral fingers, whereby said struts form abutments distributing the stresses applied from the arcs of an element to the arcs of a contiguous element and preventing simultaneously unlocking of the
10. The structure as set forth in claim 1, wherein the arcs of each element are connected by plane reinforcing members with the top surfaces thereof
11. The structure as set forth in claim 10, wherein the reinforcing members
12. The structure as set forth in claim 10, wherein the reinforcing members are formed beneath a plane delimited by the highest portion of the
13. The structure as set forth in claim 10, wherein the tops of the upstanding fingers protruding from the reinforcing members all extend to
14. The structure as set forth in claim 11, wherein additional small plane reinforcing members are formed between the arcs of each element into the
15. The structure as set forth in claim 1, wherein struts are further provided connecting the adjacent arcs of each element.
2. The structure as set forth in claim 1, wherein the arcs are each delimited at the median portion thereof of a V-shaped part whereby the V-shaped part of successive arcs of an element delimit a slot similar to a groove delimited by the overlapping arcs of two contiguous imbricated
3. The structure as set forth in claim 2, wherein the arcs and the V-shaped parts provided in the median portion thereof have a size and shape depending upon the usual width of a ski whereby said ski width covers at
4. The structure as set forth in claim 1, wherein the upstanding fingers are cone-shaped with the tops thereof extending in a same horizontal plane, said fingers having substantially identical apex angles, the bases of said fingers, at levels where joined to said arcs, each having a correspondingly varied diameter depending on the height of the respective fingers to substantially equalize the bending strength of said fingers.
5. The structure as set forth in claim 1, wherein two adjacent protruding fingers of a same arc are separated by an interval which is substantially equal to the smallest interval separating two imbricated contiguous arcs, whereby the number of fingers is substantially constant per unit of surface in all directions of a sheet constituted by said imbricated
6. The structure as set forth in claim 1, wherein the enlarged protuberances are ball shaped and protrude above the filiform of the arcs to constitute bearing surfaces for a ski upon considerable bending over of
7. The structure as set forth in claim 1, wherein lateral fingers protrude from each side of each arc, the lateral fingers on one half side protruding rearwardly and the lateral fingers on the other half side protruding forwardly, said lateral fingers being upwardly bent substantially following the bend of the arc supporting the same, whereby they constitute locks when the arcs of two contiguous elements are
8. The structure as set forth in claim 7, wherein struts are further
9. The structure as set forth in claim 8, wherein said struts connect said arcs just above the lateral fingers, whereby said struts form abutments distributing the stresses applied from the arcs of an element to the arcs of a contiguous element and preventing simultaneously unlocking of the
10. The structure as set forth in claim 1, wherein the arcs of each element are connected by plane reinforcing members with the top surfaces thereof
11. The structure as set forth in claim 10, wherein the reinforcing members
12. The structure as set forth in claim 10, wherein the reinforcing members are formed beneath a plane delimited by the highest portion of the
13. The structure as set forth in claim 10, wherein the tops of the upstanding fingers protruding from the reinforcing members all extend to
14. The structure as set forth in claim 11, wherein additional small plane reinforcing members are formed between the arcs of each element into the
15. The structure as set forth in claim 1, wherein struts are further provided connecting the adjacent arcs of each element.
Description:
BACKGROUND OF THE INVENTION
With the ever increasing popularity of snow skiing as a recreation and sport, there has been an increasing demand for artificial surfaces simulating snow skiing conditions but which may be used at above-freezing temperatures, either indoors or outdoors. Such surfaces particularly are useful for training purposes because they are not subject to weather conditions, the slope or angle and contour readily may be predetermined and they are considerably safer, especially for beginners, than the frozen ground. Such surfaces must be capable of providing a skiing surface approximating that of good snow conditions and also be sturdy and wear resistant to avoid damage that would require frequent replacement.
SUMMARY OF THE INVENTION
According to the invention, the flexible structure comprises a plurality of similar elements, each having a cross-piece connecting parallel and substantially filiform arcs, said elements being partially imbricated together and the arcs having a top provided on each side thereof with a number of protuberances, said protuberances being separated by flexible protruding fingers, and the base of said fingers being placed at a level lower than top of said protuberances.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a section of one of the elements constituting the flexible structure of the invention;
FIG. 2 is a side view showing how the successive elements of the structure respectively are placed;
FIG. 3 is a partial perspective view of two elements, said perspective showing a particular characteristic of the invention;
FIG. 4 is a partial perspective top view of two assembled elements and shows another characteristic of the invention;
FIG. 5 is a perspective view similar to FIG. 1 and showing an additional development of the invention, and
FIGS. 6 and 7 are partial plan views showing the assembling of two elements in two different positions.
DETAILED DESCRIPTION OF THE INVENTION
Each constituting element of the structure comprises one or two parallel girders 1 and 2 with arcs 3, 3a . . . 3n extending therefrom. As shown in the drawings, the arcs each delimit two bearing portions 4 and 5 designed to be placed on a supporting surface, such as the ground, and a curved portion 6.
One of the girders, for example the girder 1, is provided with hooks 7 placed between two successive arcs, each hook 7 being designed to hold the girder 2 for maintaining the arcs closed. Laterally, the arcs form two series of protruding fixing components 8, 8a . . . 8n and 9, 9a . . . 9n. The fixing components can, for example, be constituted by rings and, in such a case, rings 8 are placed at a level slightly lower than rings 9 to enable these rings to be superposed as shown in FIG. 2 thus making possible the placing of a locking device 10, for example a pin, therethrough.
FIG. 2 shows that series of elements can thus be imbricated, the junction between the elements being made alternately between the even row elements and the odd row elements, as shown in FIG. 2 by elements I, II and III. Each arc 3 is provided, at top thereof, with a V-shaped part 11 having an upwardly directly concavity. The shape and width of the parts 11 are designed to have substantially the shape and width of grooves 12 delimited by the arcs of two successive elements, such as the elements I and II when they are assembled as shown in FIG. 2.
Thus the arcs of the successive elements delimit grooves having a small depth and a small width, the distribution of the same being designed in view of enabling a ski, 13, to normally cover the slots formed by two parts 11 and the groove 12 separating two parts 11.
On each side of part 11, the arcs 3 are provided with respective protuberances 14 and 15, having, for example the shape of balls. Furthermore, the arcs are provided, between protuberances 14 and 15, with fingers 16 of a variable length so that the tops of said fingers extend in a same horizontal plane, as shown in FIG. 2.
The fingers 16 have a small cross-section and are in the shape of a truncated cone with all of them preferably having the same apex angle; consequently the base of the fingers are of variable surface area according to length thereof as well shown in FIG. 2, thus causing flexibility of all the fingers 16 to be substantially the same. Each element is made of a single piece and for example of thermoplastic synthetic resin to have a good flexibility.
FIG. 3 shows that it is also advantageous that the internal distance a separating two successive arcs of a same element, for example arcs 3, 3a, be approximately double the distance b separating two successive fingers 16 of a same arc. Thus when the arcs 3, 3a of element II are imbricated into the arcs 3 1 , 3a 1 of element I, the fingers 16 of successive arcs are substantially equidistant so that the ski 13 rests on a same number of fingers 16, whatever may be the direction of the ski in relation with the plane delimited by each arc. Consequently, there is no difference of sliding for the skier if he runs on a direct track or on a crossing track.
It is also to be noted that the base of the fingers 16 is always at a level lower than the bearing surfaces constituted by the protuberances 14 and 15, thus the base of the fingers 16 can never be directly caught by the square edges 13a of the ski 13, whereby the fingers 16 are protected from any chance of being severed.
In addition to the above described use, the protuberances 14 and 15 constitute both bearing elements for the ski 13 when the fingers 16 are very bent, for example when a skier is skidding, and reinforces stiffness for the arcs 3 without preventing bending of said arcs under high stresses as can happen when a skier is skidding and a fortiori if said skier is falling down.
FIG. 4 shows an additional development of the invention whereby the arcs 3, 3a . . . 3n are connected by struts 17 preferably extending between the lower protuberances 14 1 , 15 1 located on said arcs. In addition, lateral fingers 18 are designed on one of the sides of the arcs to protrude for example towards the left, and fingers 19 on the other side of said arcs to protrude towards the right. Also preferably, the fingers 18 and 19 are upwardly bent in the same direction as that of the portion of arcs which form the same and they diverge as shown in the drawings. A ball 20 is advantageously placed at the end of each finger 18, 19.
When two elements I and II are assembled as hereinbefore described a resilient deformation of the fingers 18 and 19 has been required to imbricate them which mutually lock the arcs of two imbricated elements, thus ensuring their connection. The struts 17 constitute stops or abutments which, upon deformation of the arcs of an element, bear on the arcs of the contiguous element preventing the unlocking of the fingers 18, 19 and distributing from one element to the other element the stresses causing the deformations. The fingers 18 and 19 eliminate the necessity for the rings 8, 9, previously designed in relation with FIGS. 1-3.
According to FIGS. 5 to 7, the arcs are still connected, at the level of the lower protuberances 14 and 15, by connecting element 21. Also in addition, the successive arcs are connected by planar reinforcing members or strips 22 placed in zigzag and connecting for example the two protuberances 14 of an arc to the two protuberances 15 of the next following arc. The members 22 are formed at the level of the arcs to enable their upper surface to be slightly under the level of the protuberances 14, 15. The members 22 support upstanding fingers 16a, the free ends of which are disposed in the same plane with the free ends of the fingers 16.
As shown in FIGS. 6 and 7, the elements can be assembled so that the planar reinforcing members 22 are disposed in a diamond-shape or in a herring-bone pattern. Besides, the members 22 and also the connecting elements 21, through connecting the different arcs together, restrict their bending when a skier is moving, especially upon skidding, the move being made easier due to the adherence provided by the fingers 16a to the skis when the same are bearing on edge thereof.
Since the reinforcing members 22 are at a level slightly lower than the level of the protuberances 14, 15, the skis cannot engage the base of the fingers 16a consequently said fingers are protected against being cut off but can freely bend and take again their original position after passage of a ski. The members 22 can be placed in any desired way, and in this respect FIG. 5 shows that segments of reinforcing members can form zigzags between two successive arcs, while FIGS. 6 and 7 show segments of reinforcing members respectively extending between several arcs. In such a case it is advantageous that small strips or reinforcing members 23 such for example, as triangles, be disposed inside each zigzag delimited by the members 22. Fingers 16a also protrude from the members 23 to prevent an interval between two contiguous connecting segments 21 and to form a more continuous guide-track for a ski.
With the ever increasing popularity of snow skiing as a recreation and sport, there has been an increasing demand for artificial surfaces simulating snow skiing conditions but which may be used at above-freezing temperatures, either indoors or outdoors. Such surfaces particularly are useful for training purposes because they are not subject to weather conditions, the slope or angle and contour readily may be predetermined and they are considerably safer, especially for beginners, than the frozen ground. Such surfaces must be capable of providing a skiing surface approximating that of good snow conditions and also be sturdy and wear resistant to avoid damage that would require frequent replacement.
SUMMARY OF THE INVENTION
According to the invention, the flexible structure comprises a plurality of similar elements, each having a cross-piece connecting parallel and substantially filiform arcs, said elements being partially imbricated together and the arcs having a top provided on each side thereof with a number of protuberances, said protuberances being separated by flexible protruding fingers, and the base of said fingers being placed at a level lower than top of said protuberances.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a section of one of the elements constituting the flexible structure of the invention;
FIG. 2 is a side view showing how the successive elements of the structure respectively are placed;
FIG. 3 is a partial perspective view of two elements, said perspective showing a particular characteristic of the invention;
FIG. 4 is a partial perspective top view of two assembled elements and shows another characteristic of the invention;
FIG. 5 is a perspective view similar to FIG. 1 and showing an additional development of the invention, and
FIGS. 6 and 7 are partial plan views showing the assembling of two elements in two different positions.
DETAILED DESCRIPTION OF THE INVENTION
Each constituting element of the structure comprises one or two parallel girders 1 and 2 with arcs 3, 3a . . . 3n extending therefrom. As shown in the drawings, the arcs each delimit two bearing portions 4 and 5 designed to be placed on a supporting surface, such as the ground, and a curved portion 6.
One of the girders, for example the girder 1, is provided with hooks 7 placed between two successive arcs, each hook 7 being designed to hold the girder 2 for maintaining the arcs closed. Laterally, the arcs form two series of protruding fixing components 8, 8a . . . 8n and 9, 9a . . . 9n. The fixing components can, for example, be constituted by rings and, in such a case, rings 8 are placed at a level slightly lower than rings 9 to enable these rings to be superposed as shown in FIG. 2 thus making possible the placing of a locking device 10, for example a pin, therethrough.
FIG. 2 shows that series of elements can thus be imbricated, the junction between the elements being made alternately between the even row elements and the odd row elements, as shown in FIG. 2 by elements I, II and III. Each arc 3 is provided, at top thereof, with a V-shaped part 11 having an upwardly directly concavity. The shape and width of the parts 11 are designed to have substantially the shape and width of grooves 12 delimited by the arcs of two successive elements, such as the elements I and II when they are assembled as shown in FIG. 2.
Thus the arcs of the successive elements delimit grooves having a small depth and a small width, the distribution of the same being designed in view of enabling a ski, 13, to normally cover the slots formed by two parts 11 and the groove 12 separating two parts 11.
On each side of part 11, the arcs 3 are provided with respective protuberances 14 and 15, having, for example the shape of balls. Furthermore, the arcs are provided, between protuberances 14 and 15, with fingers 16 of a variable length so that the tops of said fingers extend in a same horizontal plane, as shown in FIG. 2.
The fingers 16 have a small cross-section and are in the shape of a truncated cone with all of them preferably having the same apex angle; consequently the base of the fingers are of variable surface area according to length thereof as well shown in FIG. 2, thus causing flexibility of all the fingers 16 to be substantially the same. Each element is made of a single piece and for example of thermoplastic synthetic resin to have a good flexibility.
FIG. 3 shows that it is also advantageous that the internal distance a separating two successive arcs of a same element, for example arcs 3, 3a, be approximately double the distance b separating two successive fingers 16 of a same arc. Thus when the arcs 3, 3a of element II are imbricated into the arcs 3 1 , 3a 1 of element I, the fingers 16 of successive arcs are substantially equidistant so that the ski 13 rests on a same number of fingers 16, whatever may be the direction of the ski in relation with the plane delimited by each arc. Consequently, there is no difference of sliding for the skier if he runs on a direct track or on a crossing track.
It is also to be noted that the base of the fingers 16 is always at a level lower than the bearing surfaces constituted by the protuberances 14 and 15, thus the base of the fingers 16 can never be directly caught by the square edges 13a of the ski 13, whereby the fingers 16 are protected from any chance of being severed.
In addition to the above described use, the protuberances 14 and 15 constitute both bearing elements for the ski 13 when the fingers 16 are very bent, for example when a skier is skidding, and reinforces stiffness for the arcs 3 without preventing bending of said arcs under high stresses as can happen when a skier is skidding and a fortiori if said skier is falling down.
FIG. 4 shows an additional development of the invention whereby the arcs 3, 3a . . . 3n are connected by struts 17 preferably extending between the lower protuberances 14 1 , 15 1 located on said arcs. In addition, lateral fingers 18 are designed on one of the sides of the arcs to protrude for example towards the left, and fingers 19 on the other side of said arcs to protrude towards the right. Also preferably, the fingers 18 and 19 are upwardly bent in the same direction as that of the portion of arcs which form the same and they diverge as shown in the drawings. A ball 20 is advantageously placed at the end of each finger 18, 19.
When two elements I and II are assembled as hereinbefore described a resilient deformation of the fingers 18 and 19 has been required to imbricate them which mutually lock the arcs of two imbricated elements, thus ensuring their connection. The struts 17 constitute stops or abutments which, upon deformation of the arcs of an element, bear on the arcs of the contiguous element preventing the unlocking of the fingers 18, 19 and distributing from one element to the other element the stresses causing the deformations. The fingers 18 and 19 eliminate the necessity for the rings 8, 9, previously designed in relation with FIGS. 1-3.
According to FIGS. 5 to 7, the arcs are still connected, at the level of the lower protuberances 14 and 15, by connecting element 21. Also in addition, the successive arcs are connected by planar reinforcing members or strips 22 placed in zigzag and connecting for example the two protuberances 14 of an arc to the two protuberances 15 of the next following arc. The members 22 are formed at the level of the arcs to enable their upper surface to be slightly under the level of the protuberances 14, 15. The members 22 support upstanding fingers 16a, the free ends of which are disposed in the same plane with the free ends of the fingers 16.
As shown in FIGS. 6 and 7, the elements can be assembled so that the planar reinforcing members 22 are disposed in a diamond-shape or in a herring-bone pattern. Besides, the members 22 and also the connecting elements 21, through connecting the different arcs together, restrict their bending when a skier is moving, especially upon skidding, the move being made easier due to the adherence provided by the fingers 16a to the skis when the same are bearing on edge thereof.
Since the reinforcing members 22 are at a level slightly lower than the level of the protuberances 14, 15, the skis cannot engage the base of the fingers 16a consequently said fingers are protected against being cut off but can freely bend and take again their original position after passage of a ski. The members 22 can be placed in any desired way, and in this respect FIG. 5 shows that segments of reinforcing members can form zigzags between two successive arcs, while FIGS. 6 and 7 show segments of reinforcing members respectively extending between several arcs. In such a case it is advantageous that small strips or reinforcing members 23 such for example, as triangles, be disposed inside each zigzag delimited by the members 22. Fingers 16a also protrude from the members 23 to prevent an interval between two contiguous connecting segments 21 and to form a more continuous guide-track for a ski.