EP1479986B1 - Starting track for ski jump - Google Patents

Abstract

The starting track has at least one cooling track (1) with at least two walls (22) and at least one base (24). Snow, in particular artificial snow (60), can be inserted into the cooling track. A cooling device (26) keeps the cooling track cool. There may also be an alternative starting track with a slippery metal, ceramic or glass surface.

Description

The invention relates to a run-in track for ski jumps. Such start-up tracks regularly provide a pair of ruts, so that there is a rut for each jump skier of the ski jumper.

Previously known are start-up tracks, in which the two ruts are formed in a continuous, located on the ski surface snow or ice cover. Furthermore, from the German utility model 200 11 567 a run-in track is known in which the bottom of the ruts is formed of metallic Gleitspurschindeln. The surface design and coating of the slip track shingles allows the ski jumpers to slide down the run-in track similar to snow.

It is also known from the DE 198 43 901 C2 a method for preserving snow and a cooling mat device for carrying out this method. Method and device are used for the preservation of snow on mountain slopes and ski slopes. The DE 196 38 714 A1 discloses a mat-like heat exchanger for cooling and / or heating purposes. From the CH 174 772 and the CH 174 551 Freezers for artificial ice rinks are known.

The previously known tarnishing tracks for ski jumping hills have the disadvantage that they can only be used to a limited extent. The molded into the closed snow blanket track first assumes that sufficient amounts of snow are available. If the jump is not covered by sufficient natural snow due to unfavorable weather conditions, natural snow and / or artificial snow must be brought in with considerable effort and applied to the jump. In unfavorable, especially changing weather conditions, the snowpack on the ski jump is also very limited shelf life. Even in the winter months, the temperatures in the vicinity of the mostly located in the valleys ski jumping hills partly clear and for longer duration above freezing. Permanently constant snow or ice conditions can therefore not be provided regularly on the previously known ski jumps even over the winter months.

The snow-free inrun track known from German Utility Model 200 11 567 can not be used for official competitions since the competition conditions require a start on snow or ice. The snowless inrun track can therefore only be used for training purposes.

From the publication DE 3003069 A1 a ski track element is known which comprises cooling pipes for cooling the ski track.

Based on the prior art, it is therefore an object of the present invention to propose an improved starting track for ski jumps. In particular, the inrun track according to the invention should ensure authentic and as constant as possible start-up conditions on snow or ice over a longer period of time. Above all, the influence of the weather on the snow or ice conditions in the inrun track should be limited. Furthermore, the inrun track according to the invention should be easy and inexpensive to manufacture and operate.

According to the invention the object is achieved by a run-in track with the features of patent claim 1. The inrun track according to the invention comprises a cooling starting track with at least two substantially vertical side walls. Down the cooling track is, for example, by a horizontally extending Floor closed, it is open at the top. Due to its box or trough-shaped profile, the cooling starting track can be filled with snow, with natural snow or artificial snow, or with a mixture of both. Furthermore, a cooling device according to the invention is provided with which the cooling starting track can be cooled to maintain the snow in it. The cooling device can be realized, for example, by a pipe system through which a coolant flows.

In addition to the cooling starting track, an alternative starting track is provided, which can be used without snow or ice support. This is achieved in that the inrun track has a sliding surface. The sliding surface may have a knobbed structure. The sliding material may consist of metal and / or ceramic and / or glass and / or other suitable materials.

Preferably, the height of the sidewalls, i. the depth of the cooling starting track is selected so that a snow depth up to 25 cm can be achieved in the cooling intake lane. To counteract slipping of the snow in the cooling track, it is convenient to attach to the bottom of the cooling track transverse webs in the height of a few centimeters, which hold the snow. The transverse webs can be part of the cooling device at the same time. The width of the cooling track should be chosen so that it does not significantly exceed the width required for two ruts. For a regular width of about 45 cm will be sufficient. The cooling track can be additionally isolated to reduce the cooling effort.

With the invention, the desired advantages are achieved. By cooling the snow or ice conditions in the cooling intake lane can be kept costly even in changing weather conditions over a relatively long period. Since only the preferably approximately 45 cm wide cooling track must be cooled, the snow or ice to be cooled and thus the Kühlauf wall is comparatively low. Thus, the constant conditions can be produced relatively inexpensively. The invention provides in this way independence from the weather and thus the desired by event organizers high security event.

The sliding surface makes it possible for the ski jumpers in the alternative starting track without snow cover to slide down the inrun track in a similar way to snow. The combination of a cooling starting track with an alternative starting track allows a multi-functional use in all weather conditions and in different seasons. In the winter season (November to March), due to the lower average temperatures, the snow or the ice in the cooling track can be obtained so that the cooling track can be used continuously even in the case of weather fluctuations. In the warm summer season, the alternative track can be used for training purposes. Thus, the same ski jump can be used year-round for ski jumping. In particular, a change from winter to summer operation is possible without structural changes.

In a further advantageous embodiment, the cooling inrun track is formed from a pair of cooling ruts running parallel next to one another. Each of the two cooling grooves has two side walls which, together with the base therebetween, give the cooling grooves, which are open at the top, a generally U-shaped cross-section. Due to their box profile, the cooling ruts can be filled with snow, with natural snow or artificial snow, or with a mixture of both. In this embodiment, it is sufficient to cool only the cooling ruts, whereby the amount of snow or ice to be cooled is further reduced.

In a preferred embodiment, the cooling takes place at the bottom of the cooling grooves, in particular in that the bottom of the cooling grooves is configured as a cooling base, which is flowed through by a coolant. In another embodiment, the cooling takes place on the side walls of the cooling grooves, wherein the walls can be configured as cooling walls, which are flowed through by a coolant. Likewise, the cooling can be done both on the ground and on the walls of the cooling grooves, in particular by the fact that a cooling bottom and cooling walls are provided, which are flowed through by a coolant. By the cooling only on the ground, the cooling costs can be reduced. By cooling on the ground and on the side walls, the snow metamorphosis can be delayed from snow to ice, so that the snow conditions remain constant over a longer period.

Advantageously, the width of the cooling grooves is chosen so that it slightly exceeds the width of a jump skis. This allows the jump skis to be received on the one hand with lateral play in the cooling raceway, on the other hand, the required amount of snow is reduced by limiting the width of the cooling ruts. Particularly suitable is a width of the cooling grooves of 13.5 cm. Advantageously, the distance between the center axes of the cooling grooves is chosen so that it corresponds approximately to the distance of the jump animal during startup on the hill. Most suitable is the usual distance of 32 cm at ski jumping competitions.

With the above-described particular embodiment, the advantages of the invention are enhanced. The required for the ski jumping snow pad is reduced to the required minimum width, namely the width of two jump skis plus some lateral play. As a result, the required amount of snow is reduced and the cooling effort is minimized.

In a further preferred embodiment, the alternative starting track consists of a pair of alternative ruts running parallel to one another, whose bottoms are designed as a sliding surface.

It is particularly advantageous if the snow surface in the cooling starting track and the bottom of the alternative starting track are at the same height, since then the starting parabola for the ski jumpers does not change when changing from the cooling starting track to the alternative starting track. The start-up parabola determines the geometric characteristics of the start-up. For an unchanged starting parabola, therefore, the cooling starting track and the alternative starting track should be arranged relative to each other so that the snow surface in the cooling intake lane in the filled state at the same height as the bottom of the alternative start-up lane.

It is particularly advantageous if the cooling starting track and the alternative starting track are arranged offset in one another, i. when the two types of ruts, so cooling ruts and alternative ruts, are arranged alternately, so that in the space between the two cooling ruts an alternative ruts comes to rest and in the space between the two alternative ruts a Kühlspurrinne. As a result, the total width of the run-up track can be kept low, so that the additional run-up track leads only to broadening by the width of a rut. As a result, it is sometimes possible to install the advantageous combination of cooling start-up track and alternative start-up track on existing ski jumping facilities without major conversion measures.

Advantageously, the existing from cooling start track and alternative start-up track is designed as a module that can be embedded in the surface of the Schanzendeckplatte. If the inrun track sunk so far that its upper edge is flush with the surface of the Schanzendeckplatte, so you can cover the inrun track with a cover and receives a flat ramp surface. This flat surface can be covered with snow, so that the jump can also be used in a conventional manner, that is, by complete coverage of the ski jumping surface with natural and / or artificial snow and molding of the inrun track in the closed snow cover. In this way, the inrun track according to the invention allows a multifunctional use of the ski jumping facility.

In a further advantageous embodiment of the invention dynamometry plates are mounted under the bottoms of alternative ruts in the bounce area of the inrun track, preferably on the last eleven meters before the jump. The dynamometric plates are used to measure the bounce developed by the ski jumper. The fact that the dynamometric plates under each of the two alternative ruts The bounce developed by each leg can be determined separately.

In order to achieve the best possible measurement results for this force measurement, it is advantageous to mechanically decouple the bottoms of the alternative track grooves and the dynamometric plates located thereunder from the lateral border of the alternative track grooves. This can be achieved by not connecting the bottom of the alternative ruts and the dynamometric plates to the side wall of the alternative track, but moving freely in the vertical direction between the walls of the alternative ruts.

This can advantageously be achieved by a corresponding design of the dynamometric plates. These preferred dynamometric plates consist of a bottom plate and a top plate between which the force sensors, e.g. piezoelectric elements are located. The bottom plate is firmly connected to the ski jumping structure or with the built-in module. On this bottom plate, the force sensors are attached, which in turn are firmly connected to the cover plate. It is particularly favorable if the base plate and the cover plate largely assume the width of the alternative groove, so that only a narrow gap remains to the lateral border of the alternative grooves. On the cover plates of the Dynamometrieplatten then the bottom of the alternative ruts is attached. Thus, the bottom of the alternative ruts is only supported by the dynamometric plates and is free to move up and down between the lateral surrounds of the alternative ruts.

As far as parts of the cooling device, in particular cooling lines are guided through the Dynamometrieplatten, a mechanical decoupling can also be provided for this.

When staggered arranged cooling and Alternativanlaufspur, so if between the ruts of the cooling track a Alternativspurrinne and between the ruts of Alternativanlaufspur a cooling rut is, for the Equivalent ankle provided cooling and alternative ruts are also underlaid with a common Dynamometrieplatte. This is achieved by Dynamometrieplatten, which are assigned to an outer and the respectively adjacent inner track groove together. The mechanical decoupling must then take place in the middle of the four ruts between the two inner ruts. The decoupling can be done for example by a gap. Since the two right and the two left ruts are assigned to the same anklebone, the bouncing force developed by each leg of the skijumper can also be determined separately with this configuration of the dynamometric plates.

In a further advantageous embodiment, the Dynamometriepatten be mechanically decoupled in the start-up direction at regular intervals, preferably at a distance of one meter. This makes it possible to break down the strength development of the ski jumper in the take-off phase in terms of time and place. This decoupling can also be achieved by a gap between successive Dynamometrieplatten.

Fig. 1:

eine konventionelle Anlaufspur, bestehend aus einer mit Schnee gefüllten Kühlanlaufspur, bei der die Spurrinnen in den eingefüllten Schnee eingeformt sind,

Fig. 2:

eine Anlaufspur bestehend aus einer Kühlanlaufspur und ei- ner daneben angebrachten Alternativanlauspur,

Fig. 3:

eine aus einem Paar von Kühlspurrinnen gebildete Kühlan- laufspur, wobei sich die Kühleinrichtung am Boden der Kühl- spurrinnen befindet,

Fig. 4:

eine aus einem Paar von Kühlspurrinnen gebildete Kühlan- laufspur, wobei sich die Kühleinrichtung am Boden und an den Wänden der Kühlspurrinnen befindet,

Fig. 5:

eine aus einer Kühlanlaufspur und einer Alternativanlaufspur bestehende Anlaufspur, wobei die Kühlspurrinnen und die Al- temativspurrinnen ineinander versetzt angeordnet sind,

Fig. 6:

einen Schanzenbaukörper mit einem Anlauf-Kanal in der Schanzendeckplatte, in den das Anlaufspurmodul eingelassen ist,

Fig. 7:

Querschnitt durch ineinander versetzt angeordnete Kühlan- laufspur und Alternativanlaufspur, wobei die Alternativanlauf- spur mit Dynamometrieplatten unterlegt ist,

Fig. 8:

Längsschnitt durch eine Alternativspurrinne, die mit Dynamo- metrieplatten unterlegt ist,

Fig. 9:

Querschnitt durch ineinander versetzt angeordnete Kühlan- laufspur und Alternativanlaufspur, wobei die beiden linken und die beiden rechten Spurrinnen von jeweils einer gemeinsamen Dynamometrieplatte unterlegt sind,

Fig. 10:

Längsschnitt durch eine Alternativanlaufspur in einer Anlauf- spur entsprechend Figur 9.

Embodiments of the invention will be explained in detail with reference to the following figures. Showing:

Fig. 1:

a conventional inrun track, consisting of a snow-filled cooling track, in which the ruts are formed in the filled snow,

Fig. 2:

an inrun track consisting of a cooling start track and an adjacent alternative track track,

3:

a cooling starting track formed from a pair of cooling grooves, wherein the cooling device is located at the bottom of the cooling grooves,

4:

a cooling starting track formed from a pair of cooling grooves, the cooling device being at the bottom and at the walls of the cooling grooves;

Fig. 5:

a run-in track consisting of a cooling start-up track and an alternative start-up track, wherein the cooling raceways and the alternative raceways are arranged offset in one another,

Fig. 6:

a hill building body with a run-up channel in the ski jump deck, in which the inrun track module is embedded,

Fig. 7:

Cross section through mutually staggered cooling starting track and alternative starting track, wherein the alternative starting track is underlaid with dynamometric plates,

Fig. 8:

Longitudinal section through an alternative track, which is lined with dynamometric plates,

Fig. 9:

Cross section through mutually staggered cooling starting track and alternative starting track, wherein the two left and two right ruts are each underlaid by a common dynamometric plate,

Fig. 10:

Longitudinal section through an alternative inrun track in a run-in track FIG. 9 ,

FIG. 1 shows a start-up track 1 for ski jumps, which consists only of a cooling starting track 20. Bottom 24 and side walls 22 of the cooling run-track 20 form a box-shaped profile. Snow 60, natural snow or artificial snow or a mixture of both, can be introduced into the cooling starting track 20.

The distance of the side walls 22 is chosen so that in the filled snow two ruts can be formed in the space required for ski jumping. On the other hand, the distance of the side walls 22 should not go well beyond the extent required to keep the cooling snow amount as low as possible. Ideally, a distance of about 50 cm appears for the side walls 22. At the bottom of the cooling start track, the cooling device 26 is provided, which can be realized for example by a flowed through by a coolant pipe plant.

FIG. 2 shows a run-in track 1 consisting of a cooling inrun track 20 and a directly adjacent arranged Alternativanlaufspur 40. The cooling inrun track 20 corresponds to the in FIG. 1 shown. The alternative ruts 50 and 51 of the alternative start-up track 40 have a sliding surface so that the alternative start-up track can be operated without snow. The width and spacing of the alternative starting ruts are selected according to the requirements of ski jumping. Preferably, a track interior width of about 13.5 cm and a distance between the center lines of the track grooves of 32 cm is selected.

FIG. 3 shows a run-up track 1, which consists of a cooling run-track 20, wherein the cooling run-up track 20 is formed of two parallel adjacent cooling grooves 30 and 31. The two cooling grooves 30 and 31 are in turn formed from the walls 22 and the bottom 24. The distance b of the walls 22 of a cooling raceway 30 or 31 is selected so that the cooling raceway can accommodate a jump skis so that laterally for the purposes of ski jumping sufficient play remains. Particularly favorable is a width b of 13 to 14 cm.

The cooling grooves 30 and 31 are filled with natural and / or artificial snow 60. Since only the preferably 13 to 14 cm wide cooling grooves 30 and 31, but not the gap between the two cooling grooves with snow 60 must be filled, the need for snow 60 is comparatively low. In the FIG. 3 Thus, cooling intake track 20 shown permits minimizing the amount of snow required for two skipping boats, since only the two cooling ramp grooves 30 and 31 provided for each skip must be filled with snow. On the bottom 24 of the cooling grooves 30 and 31 is the cooling device 26, which ensures that the snow in the cooling grooves 30 and 31 60 is maintained even with changing outside temperatures.

FIG. 4 shows a run-in track 1, which consists of a cooling start track 20 similar to the in FIG. 3 shown consists. In contrast to FIG. 3 is in the cooling grooves 30 and 31 in FIG. 4 the cooling device 26 is mounted not only on the floor 24, but on the floor 24 and on the side walls 22. As a result, even better cooling of the snow 60 located in the cooling grooves 30 and 31 is achieved. In this way the snow metamorphosis can be delayed from snow to ice. The cooling grooves 30 and 31 preferably have a depth of 25 cm and a width b of 13 cm and a mutual distance d of 32 cm.

FIG. 5 FIG. 10 shows a start-up track representing a combination of a cooling start track 20 and an alternate start track 40. Cooling inrun track 20 and alternative inrun track 40 are arranged offset in one another, that is, in the horizontal direction, cooling grooves 30 and 31 alternate with alternative ruts 50 and 51. In FIG. 5 there is a cooling lane 30 on the left, an alternative lane 50 on the right, a cooling lane 31 on the right next to it, and an alternative lane 51 on the far right. Of course, the reverse sequence is also possible.
The staggered arrangement of cooling track 20 and Altemativanlaufspur 40 allows to accommodate the two starting tracks on minimum width.

FIG. 6 shows a Schanzenbaukörper 2 with a Schanzendeckplatte 3 in which a run-up channel 4 is inserted. In the run-up channel 4, the trained as a module inrun track 1 can be sunk. Thus, it can be achieved that the snow surface in the cooling grooves 30 and 31 and the bottom 44 of the alternative ruts 50 and 51 at the same height as the surface of the Schanzendeckplatte 3. This has the consequence that the characteristic for the ski jump start parabola for the inrun track 1 is the same as that for the surface of the Schanzendeckplatte 3. As a result, the starting parabola is not changed by the use of the inrun 1 against the normal ski surface.

FIG. 7 shows a run-in track 1 with mutually offset cooling and Alternativanlaufspur in cross section. The bottoms 44 of the alternative ruts 50 and 51 are underlaid with dynamometric plates 46. With the Dynamometrieplatten 46, the force pulses developed by the ski jumpers can be measured, and separately for each talus. The measurement can be carried out, for example, by piezoelectric elements integrated into the dynamometric plates 46. Accurate measurement requires mechanical decoupling of the bottoms 44 of the alternative track grooves 50 and 51 and the dynamometry plates 46 from the lateral enclosure of the alternative track grooves 50 and 51. This mechanical decoupling may be achieved, for example, by a narrow gap 48 between the dynamometric plate 46 and the walls 22 and 42 , The gap is preferably 2.5 mm wide. The complete mechanical decoupling of the dynamometric plates also requires a mechanical decoupling 47 of coolant lines optionally passing through the dynamometric plate. The decoupling 47 can be achieved for example by flexible coolant lines.

FIG. 8 shows a longitudinal section through an alternative ruts 50 or 51, wherein the bottom 44 of the alternative ruts 50 is backed by dynamometry plates 46.
FIG. 8 shows in the middle a complete Dynamometrieplatte 46 and right and left adjacent Dynamometrieplatten 46 each half. The dynamometry plates 46 consist of a bottom plate 55, a cover plate 56, and force sensors 57 mounted therebetween. The force sensors may include, for example, piezoelectric elements. The bottom plate 55 is fixed on the ski surface or on the module carrier. The cover plate is non-positively connected to the bottom of the alternative rut. The dynamometric plates are mechanically decoupled in the start-up direction at regular intervals. The mechanical decoupling can be achieved by a narrow gap 49 between two successive Dynamometrieplatten 46. Preferably, the gap is a few millimeters wide. The mechanical decoupling in the start-up direction allows an analysis of the bounce developed by the Springer, which is resolved by time and place.

FIG. 9 shows a mutually offset cooling and Alternativanlaufspur 20, 40. The left cooling groove 30 and the left alternative furrow 50 are underlaid by a common Dynamometrieplatte 46. Similarly, the right cooling groove 31 and the right alternative groove 51 have a common dynamometric plate 46. The mechanical decoupling occurs between the middle tracks 50 and 31 through the gap 48. With this arrangement, the force pulses developed by the ski jumper can be measured separately for each talus independently Whether the cooling start track 20 or the alternate start track 40 is used.

FIG. 10 shows a longitudinal section along an alternative trough 50 or 51 in a run-in track according to FIG. 9 , Due to the required depth of the cooling grooves 30 and 31, the overall structure is correspondingly higher. Also in this construction, the dynamometric plates 46 are mechanically decoupled in the longitudinal direction through narrow gaps 49.

The above-described invention achieves a number of advantages. In a simple and cost-effective manner, a run-in track of snow or ice is provided, which is far less dependent on the weather conditions than previously known tarnishing tracks. As a result, a much higher degree of event security is achieved for the organizers. The combination with the Altemativanlaufspur makes the inrun track even without snow and therefore usable all year round. Due to the small space requirement, in particular the small required width, the inrun track according to the invention can also be integrated into existing ski jumping facilities, especially when the inrun track according to the invention is designed as a module. The connection with the dynamometric plates allows a particularly accurate analysis of the force impulses developed by the ski jumper. Thus, the inrun track according to the invention is particularly well suited for training purposes.

Claims (13)

1. An inrun track (1) for ski jumping hills, wherein the inrun track (1) includes at least one cooling inrun track (20), wherein the cooling inrun track has at least two walls (22) and at least one base (24), wherein snow (60), in particular artificial snow or a mixture of artificial snow and natural snow, can be introduced into the cooling inrun track (20), and wherein a cooling device (26) for cooling the cooling inrun track (20) is provided, characterised in that, in addition to the at least one cooling inrun track (20), an alternative inrun track (40) is provided, with the alternative inrun track (40) having a sliding surface, in particular sliding naps, made of metal and/or ceramic material and/or glass and/or other materials so that the alternative inrun track (40) can be used without a snow cover.
2. An inrun track (1) for ski jumping hills in accordance with claim 1, characterised in that the at least one cooling inrun track (20) includes a pair of cooling track grooves (30, 31) extending parallel next to one another, with the cooling track grooves (30, 31) having a substantially U-shaped cross-section, with the snow (60) being able to be introduced into the cooling track grooves (30, 31), and with the cooling track grooves (30, 31) being able to be cooled by the cooling device (26).
3. An inrun track (1) for ski jumping hills in accordance with claim 2, characterised in that the cooling device (26) is provided at the bases (24) and/or at the walls (22) of the cooling track grooves (30, 31); and in particular in that the cooling device (26) is integrated into the bases (24) and/or into the walls (22).
4. An inrun track (1) for ski jumping hills in accordance with one of the claims 2 or 3, characterised in that the width (b) of the cooling track grooves (30, 31) is selected so that the cooling track grooves (30, 31) can each receive a jumping ski.
5. An inrun track (1) for ski jumping hills in accordance with one of the preceding claims, characterised in that the alternative inrun track (40) includes a pair of alternative track grooves (50, 51) extending in parallel next to one another, with the bases (44) of the alternative track grooves (50, 51) having the sliding surface, in particular the sliding naps made of metal and/or ceramic material and/or glass and/or other materials.
6. An inrun track (1) for ski jumping hills in accordance with one of the preceding claims, characterised in that snow can be introduced into the cooling inrun track (20) to such a height that the snow surface is at the same level as the base (44) of the alternative inrun track (40).
7. An inrun track (1) for ski jumping hills in accordance with either of claims 5 or 6, characterised in that a cooling inrun track (20) is provided which comprises two cooling track grooves (30, 31) and an alternative inrun track (40) which comprises two alternative track grooves (50, 51); and in that the cooling inrun track (20) and the alternative inrun track (40) are arranged offset into one another so that an alternative track groove (50) is located between the cooling track grooves (30, 31) and a cooling track groove (31) is located between the alternative track grooves (50, 51).
8. An inrun track (1) for ski jumping hills in accordance with one of the preceding claims, characterised in that the inrun track (1) can be lowered as a module in a track channel (4) in the jump cover plate (3).
9. An inrun track (1) for ski jumping hills in accordance with one of the claims 5 to 8, characterised in that dynamometric plates (46) are attached beneath the bases (44) of the alternative track grooves (50, 51) in the takeoff region of the inrun track (1), preferably over the last 11 meters before takeoff, with the force developed by the ski jumper being measurable by the dynamometric plates (46).
10. An inrun track (1) for ski jumping hills In accordance with the preceding claim, characterised in that the bases (44) of the alternative track grooves (50, 51) and the dynamometric plates (46) attached thereunder are laterally mechanically decoupled, with the mechanical decoupling preferably being achieved by a gap (48) on both sides of the bases (44) and of the dynamometric plates (46).
11. An inrun track (1) for ski jumping hills in accordance with one of the two preceding claims, characterised in that the dynamometric plates (46) include a base plate (55), a cover plate (56) and force sensors (57) located therebetween, with the base plate (55) being fixedly connected to the jump (2), with the cover plate (56) being fixedly connected to the base (44) of the alternative inrun track grooves, and with the cover plates (56) preferably extending approximately over the whole width of the bases (44) of the alternative track grooves (50, 51).
12. An inrun track (1) for ski jumping hills in accordance with claim 7, characterised in that dynamometric plates (46) are attached beneath the track grooves (30, 31, 50, 51) in the takeoff region of the inrun track, preferably over the last 11 meters, which are jointly associated with an outwardly disposed track groove (30, 51) and the respective adjacent inwardly disposed track groove (31, 50), with a mechanical decoupling (58) which is preferably established by a gap (58) being provided between the inwardly disposed track grooves (31, 50).
13. An inrun track (1) for ski jumping hills in accordance with one of the claims 9 to 12, characterised in that the dynamometric plates (46) are mechanically decoupled in the inrun direction at regular intervals, preferably at an interval of one meter, with the decoupling preferably being established by a respective gap (49).

Images