Snow surface compactor and track apparatus
The invention relates to a snow compactor 1 and a fixing device 24 for the track body for fastening to the same. The snow compactor 1 can be made to oscillate by the excitation apparatus 2 and thus acts in a planar fashion upon the snow to be compacted by way of its floor plate 3. It comprises a mounting apparatus 4 for attachment to the tractor. The floor plate 3 comprises a reinforcing structure 5 and a front region which is situated at the front in the working direction A of the snow compactor 1 and which is upwardly bent. The special aspect in the snow compactor 1 in accordance with the invention is that the excitation apparatus 2 is arranged behind the center of gravity S. As a result, it acts especially with the rear region of its floor plate 3 in a planar fashion upon the snow situated beneath the snow compactor 1. As a result of the near continuous curved floor plate it is possible in an especially simple way by turning the snow compactor 1 to change the produced surface structure without having to attach or remove the fixing device 24 or the track body 23 for profiling.
The invention relates to a snow surface compactor in accordance with the preamble of claim 1 and a track apparatus for use on a snow surface compactor.
Snow surface compactors are used for preparing the snow surface especially for winter sports. In this connection this also concerns the preparation of the respective surface of the snow, with the same being smoothed and compacted. The snow surfaces shall be understood as being ski slopes, cross-country ski runs, ski jumps, freestyle facilities such as half-pipes or fun parks.
The most common embodiment of such a snow surface compactor concerns a snow blower drawn by a snow cat with heavy rubber, plastic or steel plates which are attached to the same and consist of several elements. In such snow compactors, the snow or ice clumps are cut down by the snow blower and smoothed and compacted thereafter by the action of the weight of the plates drawn over the surface of the snow. Since these plates rest on the snow and compress the affected snow surface by their weight, this is called static compaction.
In contrast to such statically compacting snow compactors, there have recently been dynamically acting snow compactors which can be used in addition to or completely without a snow blower. In the case of such dynamic snow compactors, a plate is made to oscillate by an excitation apparatus. As a result of periodic vibrations of the plate, the respective snow surface is compressed especially strongly and compacted to a substantially higher extent than is the case with purely statically acting rubber, plastic or steel plates.
The stability of a slope or ski run prepared with a dynamic snow compactor is considerably higher than in the conventionally prepared snow surfaces.
This increases the comfort for the users of the respective snow surfaces and offers considerable cost benefits in maintaining the slopes and ski runs because the snow surfaces need not be prepared as often while maintaining the same surface quality. The known dynamic snow compactors are already used with much success. There is a desire however to further improve the smoothness of running and the field of applications of the snow compactors.
The invention is therefore based on the object of providing a dynamic snow compactor whose smoothness of running is improved further as compared with the previously disclosed solutions and offers an increased range of applications.
This object is achieved by a snow compactor in accordance with claim 1. Advantageous further developments are described in the sub-claims.
The snow compactor in accordance with the invention therefore concerns a dynamically acting compactor with a baseplate which can be made to oscillate by an excitation apparatus and acts in a planar manner on the snow to be compacted. Said baseplate comprises a front region which is situated in the front in a working direction of the snow compactor and is upwardly bent, and further comprises a reinforcing structure. Said reinforcing structure can advantageously be an especially light and stiff cellular structure. Moreover, the snow compactor comprises mounting apparatus for attachment to a tractor which as far as possible is vibration-dampened in order to avoid transmitting vibrations from the snow compactor onto the tractor.
The snow compactor in accordance with the invention differs from the known compactors especially in such a way that the excitation apparatus is arranged in the working direction behind the center of gravity of the snow compactor. As a result, the oscillation amplitude is increased in the direction of the rear edge of the snow compactor and the compacting effect is increased.
This property shows considerable advantages especially in compacting larger amounts of snow and new snow. Whereas the known dynamic snow compactors can dig into the snow or tend to wobble or tilt, the snow compactor in accordance with the invention slides over the snow in a secure and stable manner. That is why the preparation of the snow surface can also occur at a higher speed than known previously.
A predominant part of the baseplate of the snow compactor is preferably curved. The snow compactor thus stands on a very narrow strip as compared with a compactor with a planar baseplate. In other words, its contact surface is very small. This leads to a concentration of the compaction forces on the relatively narrow contact strip. The compaction power is especially concentrated in this case, which is especially advantageous in breaking up and shattering ice surfaces.
Moreover, the snow compactor can virtually swing into its best working position and always has a forwardly upwardly bent baseplate at the usual angles of inclination. The snow compactor can therefore slide very well over accumulations of snow when the front region is lowered, there are strong changes of inclination or very deep ground waves without getting jammed or digging into the same. The snow compactor can therefore be used independent of its angle of attack relative to the snow surface to be compacted. The further improved running properties considerably extend the field of application.
A major part of the baseplate is appropriately curved with a constant curvature. This facilitates production and making of the snow compactor because conventional, circularly bent sheets or tools can be used. It is especially advantageous when the part of the baseplate which is curved with a constant curvature extends over at least two-thirds of the cross-sectional width of the snow compactor. A relatively large part of the snow compactor can be made from uniformly bent components or sheets.
In a preferred further development of the snow compactor, the baseplate comprises at least two differently arched regions, with the region situated at the rear in the working direction having a larger radius of curvature and extending at most over one-third of the cross-sectional width of the snow compactor. As a result, the rear region of the baseplate is curved to a lower extent than the region at the front, which leads to the consequence that the snow compactor will not tip over in the rearward direction so easily and at the same time comprises a large region with strong curvature which positively influences the sliding properties of the snow compactor especially in waved areas. The specific relationship between flatter and stronger curvature leads to the best possible compromise between concentrated compaction forces and effective compaction surface.
At least one track body for profiling the snow surface is preferably arranged on the snow compactor. This track body may concern massive profile strips which are grooved on their lower side and are fastened to the rear end of the snow compactor in the known manner transversally to the working direction. The snow compactor thus produces a grooved structure in the compacted snow surface.
The use of the snow compactor in accordance with the invention is especially advantageous in the preparation of cross-country ski runs such as planar skating runs or classic cross-country ski runs with two parallel tracks. The compaction which is considerably stronger as compared with that of conventional compactors leads to an improved support of the skis and the ski poles of the skiers. The skiers can therefore move more comfortably and effectively, which is why the cross-country ski runs prepared with the snow compactor in accordance with the invention are highly popular.
For preparing a cross-country ski run for classic telemark technique, at least two track bodies which extend in their length substantially in the working direction are arranged in pairs and parallel spaced from one another on the snow compactor. The track bodies then at least have a width which is slightly wider than a cross-country ski, a height which corresponds approximately to the height of cross-country ski and a substantially planar bottom side. The track bodies are arranged spaced from one another in the width of a hip, corresponding to a clearance of approx. 20 cm.
The track body is preferably arranged on the lower side of the baseplate. This is the side of the baseplate facing the snow to be compacted. The track body is appropriately fastened to the baseplate detachable by itself. Suitable fastening means can be screws or clamps for example.
In an advantageous further development, the track body is fastened with a fixing device to the snow compactor. Said fixing device for the track body suitably comprises a flexurally resistant holding arm which should be swivelable.
The fixing device for the track body appropriately comprises an adjusting means for adjusting the position and/or for setting the track depth of the track body. In this embodiment of the snow compactor it is thus possible to produce differently deep tracks in the snow. The adjusting means may concern mechanical adjusting means for example such as screws guided in oblong holes, clamp screws, turnbuckles and the like. It is also appropriate when the adjusting means is driven hydraulically. A hydraulic cylinder can be used for adjusting the fixing device for the track body. A difficult adjustment of the adjusting means by hand which is unpleasant for the operator in inclement weather can thus be avoided.
Preferably, the track body is attached to the swivelable holding arm and can be swiveled to a working position which is situated in the working direction behind the baseplate. The track body can thus be mounted on the snow compactor, but be brought to an idle position in which it is not pressed into the snow to be compacted, and thus therefore does not leave any tracks. It is thus easily possible to use the snow compactor both for profiling as well as for smoothing the snow surface. The snow compactor can be used for making telemark tracks and skating tracks without requiring any re-mounting or dismounting of the track bodies. Skating tracks are usually smooth planar snow surfaces with a width of mostly 2 to 3 m, whereas telemark tracks are usually surfaces which are structured with parallel grooves.
It is appropriate when the track body is a rotatably held wheel. This embodiment of the track body comes with the advantage that it can co-rotate with the snow to be compacted and causes only low friction. As an alternative, the track body can also be a rotatably held roller which is profiled with annular elevations and/or recesses. This embodiment comes with the advantage that the space between the elevations of the track body leads to a further smoothing of the compacted snow, whereas the elevations of the rollers press the tracks into the snow. The roller can also consist of several disks or roller segments. This has the advantage that the profile of the track body can be adjusted individually and easily by inserting roller parts of different thickness.
In an alternative embodiment of the snow compactor, the fixing device for the track body comprises a flexurally soft flat strip to which at least one track body is fastened. Flexurally soft shall be understood as a property which adjusts well to the shape of the baseplate of the snow compactor. The fixing device for the track body is not mounted on but beneath the snow compactor in this case and must be easy to bend due to the curvature of the baseplate. The flat strip is therefore appropriately a plastic mat. Metal sheet strips or webs of fabric can also be used. The flat strip itself comprises at least one holding means and a clamping means for fastening the fixing device for the track body to the snow compactor. The fixing means concerns in the simplest embodiment a claw or a clamp which can be hooked at the one end of the snow compactor. On the other side, which is appropriately situated in the working direction at the front, the flat strip comprises at least one clamping means which may concern a clamp screw. The flat strip is tightened with the help of the clamping means and pressed against the baseplate of the snow compactor.
The track bodies are fastened to the outside of the flat strip, which bodies are thus clamped in a simple and detachable way onto the bottom side of the baseplate.
The flat strip can be clamped appropriately with the outside track bodies to a profiling strip fastened to the baseplate. This means that the flat strip is either fastened itself to the profiling strip or is guided over the profiling strip.
The track body preferably extends in its length over approximately one-third of the cross-sectional width of the snow compactor. This embodiment comes with the advantage that by turning the snow compactor the track bodies are turned into a position in which they no longer press into the compacted snow. By turning the snow compactor it is thus possible to change the surface structure in the snow surface as produced by the same. On the one hand, the driver of the tractor can turn the snow compactor to a position in which the track bodies are just not pressed into the snow, which results in a smooth working surface. Alternatively, he will turn the snow compactor in such a way that the rear end is lowered and the track bodies are pressed into the snow. The snow compactor thus produces a classic cross-country ski run structure or the like in the snow.
The track body is appropriately curved in the working direction with a height decreasing in the working direction. It thus adjusts well to the outer shape of the snow compactor. It is further advantageous when the track body is a rigid body which has an upper side shaped according to the outside shape of the baseplate and/or the shape of the profiling strip. It can thus be attached in a simple manner to the baseplate from the outside and simply be placed on the strips in the case that fixedly screwed profiling strips are present.
The track body itself advantageously has a convex or V-shaped bottom side which displaces the snow to be compacted to the sides, so that a locally increased compaction value is not produced in the surfaces touched by the track body.
The object of the invention is also achieved by a track apparatus for use in a snow compactor with a track body or fixing device for a track body as described above.
The invention is now explained in closer detail by reference to the drawings, wherein:
As is indicated with arrow A in
The special aspect in the snow compactor 1 in accordance with the invention is that the excitation apparatus 2 is arranged behind the center of gravity S. The excitation apparatus 2 concerns a conventional unbalance exciter with semi-circle-like flyweights which are situated parallel with respect to each other and spaced from one another on a rotary shaft 10 extending transversally to the working direction A. As a result of the rotation of said unbalance exciter shaft 10, the snow compactor 1 is made to oscillate and thus acts in a planar way especially with the rear part of its baseplate 3 on the snow situated beneath the snow compactor 1. The exciter apparatus 2 is situated in a trough-like exciter housing 11 which is sealed with a removable cover 12 and is thus protected from obstructions by accumulated snow.
The floor plate 3 is made up of three parts. A first segment 13, which is situated at the front in the working direction, is a planar straight plate to which a middle segment 14 is adjacent, which segment is bent with a constant radius of curvature 15. The third baseplate segment 15 is adjacent to the second baseplate segment 14, which third segment starts in the embodiment shown here beneath the central point of the excitation shaft 10 and extends up to the end of the baseplate 3 situated at the rear in the working direction A. The third baseplate segment 15 is curved to a lower extent than the second baseplate segment 14. In the embodiment as shown here, the second radius of curvature 17 is twice as large with approx. 1.4 m as the first radius of curvature 15 with 0.73 m. Both curved baseplate segments 14, 15 are bent up in a circular fashion. It is also possible to use other radii or progressions of curvature.
The projections of the baseplates 13, 14, 16 onto a base lead to the partial cross-sectional widths 38, 39, 40. The total cross-sectional width B of the snow compactor 1 thus corresponds to the sum total of the partial cross-sectional widths 38, 39, 40 and is in the illustrated embodiment 0.974 m at a working width of approx. 2.5 m to 3 m. The sum total of the partial cross-sectional widths 38 and 39 is larger than ⅔ of the total cross-sectional width B of the snow compactor 1. Moreover, both the excitation apparatus 2 as well as the plate segment 16 are visibly situated in the rear third B/3 of the snow compactor 1, with the excitation shaft axis 10 being away from the rear edge of the snow compactor 1 by approx. 0.23 m.
The wearing protection 18 is situated beneath the baseplate 3. In this embodiment it consists of a plastic plate clamped onto the baseplate 3. The wearing protection 18 is hooked into a hook 19 at the rear end of the baseplate 3 and arrested by means of a screw 20 on the front end of the baseplate 3. A profiling strip 21 is mounted at the rear end of the wearing protection 18. It comprises a wave-like profile on its bottom side and extends approximately over the width of the baseplate 3. As a result of the waved structure of the profiling strip 21, the snow compactor 1 produces a rippled structure in the compacted snow.
The mounting apparatus 4 is a bracket-like plate which is welded together with the reinforcing structure and comprises two damping elements 22 on each of its sides. The snow compactor can be attached to the holding arm (not shown) of the tractor in a vibration-dampened but substantially torsionally rigid manner on said damping elements 22. The snow compactor 1 can be swiveled about an axis extending transversally to its working direction by turning the holding arm of the tractor.
In the illustrated embodiment as shown herein, the track bodies 23 are metal disk wheels which are rotatably fastened to the fixing devices 24 of the track bodies. The individual fixing device 24 consists of a swivelable rigid holding arm 25 which on its part consists of two T-shaped plates which are screwed together by means of spacer elements. The T-shaped holding arm 25 is rotatably held at one end in a fixing device 26 on the snow compactor 1. The holding arm 25 is flexibly connected at its opposite end with a bar 27. The bar 27 comprises an oblong hole 28 at its end opposite of the holding arm 25. The bar 27 is adjustably fastened in its longitudinal direction to a second fixing device 29 by said oblong hole 28. The fixing device 29 is fastened to the reinforcing structure 5.
The track body 23 or the holding arm 25 can be swiveled with the track body 23 about the coupling point 26 by loosening the screw 30 guided in the oblong hole 28. This allows easily adjusting the track body 23 in its height position with respect to the snow compactor 1. If one wishes to lower the track body 23, the screw 30 is loosened and the bar 28 is pushed in a rearward direction against the working direction A. The track body 23 thus lowers beneath the floor plate 3. The track body is in the neutral position in the working position of the snow compactor 1 as shown in
When the track body 23 is to be used, the snow compactor 1 is simply slightly tilted or twisted in a rearward direction, so that the track body 23 which is rigidly mounted on the fixing device 24 for the track body is pressed into the snow 31. The twisting of the snow compactor 1 occurs by twisting or bending the holding arm (not shown) of the tractor.
If the tractor does not offer any possibility to turn the snow compactor 1 in its angular position transversally to the working direction A, then it is appropriate to replace the bar 27 by a hydraulic cylinder 32, as shown in
The fixing device 24 as shown here is used for making the track of a single cross-country ski run. It is therefore slightly wider than a single cross-country ski run track, which means it has a width of approx. 30 cm to 50 cm. If two tracks are to be made next to one another simultaneously, a second fixing device for the track body is simply clamped onto the floor plate 3 next to the fixing device as shown here. The fixing devices 24 are therefore also narrower than the wearing protection 18 which covers the entire working width, extending transversally to the working direction A. The individual fixing devices 24 are clamped directly onto the continuous wearing protection 18. The floor plate 3 will thus not wear off next to the fixing devices 24.
Precisely as in the embodiment as shown in
Claims
1. A snow compactor (1), comprising a floor plate (3) which can be made to oscillate by an excitation apparatus (2) and acts in a planar fashion onto the snow to be compacted, and a mounting apparatus (4) for attachment to a tractor, with the floor plate (3) having a front region which is situated at the front in the working direction (A) of the snow compactor (1) and is bent upwardly, and having a reinforcing structure (5), characterized in that the excitation apparatus (2) is arranged in the working direction behind the center of gravity (S) of the snow compactor (1).
2. A snow compactor according to claim 1, characterized in that the excitation apparatus (2) is arranged in a third of a cross section of the snow compactor (1), which third is situated at the rear in the working direction (A) and which extends substantially in the working direction (A).
3. A snow compactor according to claim 1, characterized in that the excitation apparatus (2) is arranged in the working direction (A) behind the mounting apparatus (4).
4. A snow compactor according to claim 1, characterized in that a major part of the floor plate (3) is curved.
5. A snow compactor according to claim 1, characterized in that a major part of the floor plate (3) is curved with a constant curvature.
6. A snow compactor according to claim 5, characterized in that the part of the floor plate (14, 16) curved at least with a constant curvature extends at least over two-thirds of the cross-sectional width of the snow compactor (1).
7. A snow compactor according to claim 1, characterized in that the floor plate (3) comprises at least two differently strongly curved regions (14, 16), with the region (16) situated at the rear in the working direction having a larger radius of curvature (17) and extending at most over one-third of the cross-sectional width of the snow compactor (1).
8. A snow compactor according to claim 1, characterized in that at least one track body (23) for profiling the snow surface is arranged on the snow compactor (1).
9. A snow compactor according to claim 8, characterized in that for preparing a cross-country ski run at least two track bodies (23) are arranged in pairs and spaced parallel from one another on the snow compactor (1).
10. A snow compactor according to claim 8, characterized in that the track bodies (23) are arranged on the bottom side of the floor plate (3) facing the snow (31) to be compacted.
11. A snow compactor according to claim 8, characterized in that the track body (23) is detachably fastened to the floor plate (3).
12. A snow compactor according to claim 8, characterized in that the track body (23) is fastened to the snow compactor (1) by means of a fixing device (24).
13. A snow compactor according to claim 12, characterized in that the fixing device (24) comprises a flexurally rigid holding arm (25).
14. A snow compactor according to claim 13, characterized in that the holding arm (25) is swivellable.
15. A snow compactor according to claim 12, characterized in that the fixing device (24) comprises an adjusting means (27, 28, 30; 32) for adjusting the position and/or for setting the track depth of the track body (23).
16. A snow compactor according to claim 15, characterized in that the adjusting means (32) is driven in a hydraulic manner.
17. A snow compactor according to claim 13, characterized in that the track body (23) is attached to the swivelable holding arm (25) and can be swiveled to a working position situated in the working direction (A) behind the floor plate (3).
18. A snow compactor according to claim 8, characterized in that the track body (23) is a wheel.
19. A snow compactor according to claim 8, characterized in that the track body (23) is a roller profiled with annular elevations and/or depressions.
20. A snow compactor according to claim 12, characterized in that the fixing device (24) comprises a flexurally soft flat strip (36) to which the at least one track body (23) is fastened.
21. A snow compactor according to claim 20, characterized in that the flat strip (36) is a plastic mat.
22. A snow compactor according to claim 20, characterized in that the flat strip (36) comprises at least one holding means (33) and a clamping means (35) for fastening the fixing device (24) for the track body to the snow compactor (1).
23. A snow compactor according to claim 20, characterized in that the flat strip (36) can be clamped with outside track bodies (23) to a profiling strip (21) fastened to the floor plate (1).
24. A snow compactor according to claim 8, characterized in that the track body (23) extends in its length over approximately one-third of the cross-sectional width of the snow compactor (1).
25. A snow compactor according to claim 8, characterized in that the track body (23) comprises a height decreasing in the working direction.
26. A snow compactor according to claim 8, characterized in that the track body (23) is curved in the working direction (A).
27. A snow compactor according to claim 8, characterized in that the track body (23) is a rigid body which comprises a surface shaped according to the outside shape of the floor plate (3) and/or the shape of the profiling strip (21).
28. A snow compactor according to claim 8, characterized in that the track body (23) has a convex or V-shaped bottom side which faces the snow surface (31) to be compacted.
29. A track apparatus (37) for use on a snow compactor (1), comprising a track body (23) and a fixing device (24) for the track body.
Type: Application
Filed: Feb 10, 2006
Publication Date: Dec 21, 2006
Inventor: Klaus Kremer (Lehmen)
Application Number: 11/351,268
International Classification: E01C 19/22 (20060101);
