EP3336257B1 - Starting track ice milling unit for a ski-jump - Google Patents

Description

The invention relates to a start-track Eisfräseinheit for a ski jump ice maker. Such a start-track Eisfräseinheit for the ski jumping sport has at least one right milling head and a left milling head, which are each arranged on a rotatable about a rotation axis drive shaft and each having a plurality of cutting blades. These cutting blades are each formed along a cutting edge width with Fräsmesserschneidkanten. The Fräsmesserschneidkanten describe during a rotation of the left Fräskopfes a left Fräskopfmesserumfang and with a rotation of the right Fräskopfes a right Fräskopfmesserumfang. On the right-hand milling head, three or more than three cutting blades are mounted along the right-hand cutter blade periphery and on the left-hand milling head along the left-hand cutter blade periphery.
An ice cutter with such a start-track Eisfräseinheit is from the DE102014108167A1 known. After the inrun track of a ski jumping facility has been frozen, the inrun track with defined surface profiles is milled into the prepared ice layer by rotation of the milling heads and their guidance along defined paths. The surface profiles usually have a rutting surface with longitudinal grooves extending along the inrun track. On the one hand, these longitudinal grooves are important because, because of the longitudinal grooves, the jumping skis do not make sliding contact with the ice underneath. Only the flat sections of the rut surface are in sliding contact with the jumping skis. Sectionwise, there is air under the jump skis in the area of the longitudinal grooves. The ski jumper can thereby achieve higher startup speeds. On the other hand, the longitudinal grooves allow the channeled drainage of rainwater. The track itself is usually actively cooled so that it can be used even at plus degrees. It can not be prevented that it can rain during the race on the inrun track. The rainwater then follows the gravitational force, runs from the rutting surface into the longitudinal grooves and in this following the slope down the trail. Should the rainwater while draining again freeze, so it will happen in the lower areas of the grooves and thus not affect the areas that come into contact with the skis, which are referred to as rut inside surface. The situation is similar with lower amounts of fresh snow falling on the inrun track and sliding down the longitudinal grooves, thus not affecting the track areas in contact with the skier's skis.

A disadvantage of the known start-track Eisfräseinheit for a ski jumping hill ice mill is in particular that the milled Rurrinnenoberflächen viewed along the start-up direction are not flat enough. Significantly too large unevennesses come about as a result of the fact that the ice is broken out of the rut surface by means of the rotating cutting blades. The ice itself is comparatively brittle as a material, so that often larger pieces break out, as would be the case with a good spanbaren material. This is disadvantageous for ski jump jumper, because the unevenness generated along the start-up direction of the track during startup transmitted by the jump skis for the jumper are irritatingly noticeable.

The present invention is therefore based on the object to provide a start-track Eisfräseinheit for a ski jump ice machine for generating a run-in track on a ski jump, which overcomes the disadvantages mentioned.

This object is achieved by a start-track Eisfräseinheit with the features of claim 1.

According to the invention, at least one of the cutting blades with its cutting blade cutting edge is arranged relative to a parallel arrangement of the cutting blade cutting edge to the axis of rotation at an axial angle of 1 ° to 16 °, preferably 5 ° to 14 ° and more preferably 7 ° to 12 ° skewed to the axis of rotation ,

Due to the axial angle of attack, the milling cutter does not come into contact with the cutting edge of the ice at the same time as it hits the ice when it strikes the ice. At a time offset, the cutting blade cutting edge meets successively with adjacent sections of the cutting edge width on the ice surface to be processed. This is due to the axially adjusted and thus, compared to a parallel arrangement of Fräsmesserschneidkante and axis of rotation, skewed arrangement of the axis of rotation to an imaginary line through the Fräsmesserschneidkante. The position of two straight lines is called skew if you do not intersect and do not run in the same plane. If they do not intersect but run in the same plane, then the lines are parallel. Due to the skewed arrangement, the machined ice surface is successively removed in a lateral scraping movement. It is not broken out as in the prior art by a simultaneously acting over the entire track width on the ice surface Fräskopfmesser simultaneously. The scraping action produced by the inrun track ice milling unit as it travels along the inrun track also removes raised areas such as waves along the ruts, even with respect to an ideal plane. As a result, the run-in tracks can be milled with rut surfaces, which are considered to be sufficiently level for the ski jumper along the entry direction and thus ensure a smooth start on the hill. The groove surface is the imaginary plane of the flat areas between the longitudinal grooves of the inrun track. The run-up skis glides on these areas and has no mechanical contact with the ice in the area of the longitudinal grooves because of the longitudinal grooves.

In the operational installation position of the milling heads in the one ground and two inrun side walls having milled inrun track, the milling heads each have two Fräskopfseiten, which are guided in operation along the run-track side walls and each have to a Anlaufspurseitenwand. For the purposes of the invention, the cutting edge width is a dimension of the cutting blade, which differs from a Milling head side extends to the opposite Fräskopfseite the milling head and thus directly determines the width of the milled inrun track. The cutter blade cutting edge is ideally considered a straight line. Starting from this straight line, projections in the form of teeth can be provided in order to realize the longitudinal grooves already mentioned in the introduction to the introduction in the inrun track. However, the milled inrun track with longitudinal grooves represents an optimized variant. Crucial is the production of a substantially flat rut surface, with which the ski of the ski jumper stands during the start in flat sliding contact. In the simplest case, this groove surface can be formed continuously over the entire width of the inrun track. Optimized variants provide the aforementioned longitudinal grooves, so that the groove surface is divided by the one or more longitudinal grooves in several surface sections. Each of these surface sections is considered to be substantially planar in itself to allow a smooth sliding of the skis. Each of these surface sections is associated with a corresponding rectilinear section of the cutting blade cutting edge. If one connects these rectilinear sections of the cutting blade cutting edge in an imaginary straight line, then this straight line is arranged skewed in the mentioned angular range to the axis of rotation. If the rectilinear sections of the cutting blade cutting edge do not lie with respect to their respective extension direction on a common straight line, then the cutting blade has a plurality of Fräsmesserschneidkanten, each considered in itself in the said angular range skew to the axis of rotation.

The inrun track ice milling unit serves as a central component of an ice grinder for generating inrun track ruts with a rut inside surface. The ice maker with such a start-up Eisfräseinheit can be wired with electricity, or wirelessly powered by a battery or by means of a fuel-burning engine and has appropriate means for receiving power from a battery or fuel. The inrun track ice milling unit is particularly suitable for ice working in ruts with ice layers up to 10 cm thick. The inrun track surfaces Characterizing profile is determined by the structural design of the cutting blades. This usually depends on weather conditions. If a high volume of liquid, such as rain, is expected, a greater number of longitudinal grooves is preferred. During milling, the inrun track ice milling unit with the ice grinder is moved on defined paths along the approach direction of the inrun track, ie following the track course. For this purpose, the ice grinder preferably lies on the side walls of the run-in grooves themselves and / or on a rail system arranged adjacent to the run-in track. For defining defined tracks, such a rail system can be constructed from tubular profiles. The pipe profiles have different diameters and thicknesses depending on the requirements, in particular by the weight of the ice maker, by the absorption of forces caused by the milling process of the ice cutter. It is also possible to guide the ice cutter on already existing components of the hill. These components are, for example, in cross-section box-like trained inrun tracking components. Viewed in cross-section, these track components have a box bottom bounded on both sides by wall elements. These wall elements extending along the inrun track are also suitable as rails for guiding the ice grinder along a defined path.

The right or the left milling head processes respectively the right and left ruts of the inrun track. The milling heads are preferably designed in each case such that they can be inserted from above into the track groove to be machined. The left and the right milling head are arranged around a rotation axis arranged parallel to the track surface rotatable drive shaft. The axis of rotation usually runs in a horizontal direction transversely to the inrun track.

The cutting blades preferably comprise a stable water-resistant material such as steel. The cutting knives are preferably designed such that, when passing along the inrun track, along their cutting edge width, with their cutting knife cutting edges, they cover the entire length Track groove width, which is parallel to the axis of rotation and perpendicular or substantially perpendicular to the course of the inrun track.

The milling heads each have the at least three rigidly mounted, axially aligned cutting blades, which depending on the position of the axis of rotation on the track surfaces to be machined during milling more or less struck time on the ice.

In a preferred embodiment, each of the cutting blades is arranged with its Fräsmesserschneidkante in the axial angle of attack of 3 ° to 16 °, preferably 5 ° to 14 ° and particularly preferably 7 ° to 12 ° relative to the axis of rotation. Particularly preferably, each of the cutting blades is arranged at the same axial angle of attack. Through these training, the removal of ice by means of a scraping process can be further optimized.

In a preferred embodiment, at least one of the cutting blades is arranged at a radial angle of attack of 5 ° to 15 ° to an imaginary radius line between the cutting blade cutting edge of the cutting blade and the axis of rotation. The cutting blades are inserted obliquely with respect to an imaginary radius line between Fräsmesserschneidkante and rotation axis, so that they edit the inrun track during milling paddle or blade-shaped. This also makes it possible to mill starting tracks with rut surfaces, which are considered to be sufficiently flat for the ski jumper along the approach direction and thus ensure a smooth start on the hill. Due to the axial angle of attack and the resulting skewed arrangement of the cutting blade cutting edge to the axis of rotation varies the radial angle of attack along the cutting edge width.

Each of the cutting blades is preferably arranged over its cutting edge width at a radial angle of attack of 5 ° to 15 ° to an imaginary radius line between the cutting blade cutting edge of the cutting blade and the axis of rotation.

In a preferred embodiment, the right-hand milling head and the left-hand milling head have, in the region between adjacent milling blades, a milling-ice receiving section which extends from the adjacent milling blades and curves inwards towards the axis of rotation. Ice detached from the reamers by the cutter blades may be received in the cutter ice storage section. Thus, the ice, if it is not completely ejected from the rut, does not interfere with further milling. A jam of milled ice material could in extreme cases push the cutter upwards away from the inrun track, which, viewed in the start-up direction, can lead to unevenness in the rut surface.

Preferably, the cutting blades of the right milling head and the left milling head are evenly distributed over the right milling cutter blade periphery and over the left milling cutter blade periphery. By means of the uniform distribution of the cutting blades, a uniform removal of ice from the rutes can be achieved at a constant speed of movement of the inrun track ice unit. In particular, in this embodiment, depending on the position of the axis of rotation over the rut surfaces, the cutting knives more or less offset in time and dimension on the ice, while from the ruts wegbewegende cutting blades are arranged in reverse position to them, the paddle or blade-like throwing away is supported by ice from the ruts advantageous. In particular, in an even number of cutting blades preferably two cutting blades are arranged on the milling head diametrically opposite each other.

In a preferred embodiment, the right milling head and the left milling head are coaxially arranged on the same drive shaft. They are thus rotatable about a common axis of rotation. As a result, a simple construction of the start-track Eisfräseinheit with only one axis to be driven and a uniform processing of the left and right inrun track can be realized. Likewise, however, an individual suspension of the two milling heads with separate rotation axes and separate drives is conceivable.

Preferably, the right hand milling head and the left hand milling head continue to have the same number of cutting blades and are arranged along the common axis of rotation at an angle of 360 ° divided by twice the number of cutting blades along the right milling cutter periphery and offset along the left milling cutter blade periphery. As a result, the cutting blades of the right and left milling heads always come alternately in material engagement with the ice on the inrun track. In this configuration, the drive axle does not experience at the same time on both milling heads an upward force directed away from the inrun track. The simultaneity of the material interference favors in the starting direction the formation of unevenness of the rut surfaces.

The cutting blades preferably have teeth along the cutting blade cutting edges to form grooves in the rut surface. The number and shape of the teeth may vary depending on the rut dimensions. Usually, there are two to five teeth, in particular evenly spaced ruts produce with a depth of about one centimeter.

In a preferred embodiment, the cutting blades are each constructed from a plurality of Fräsmessklingen. Viewed in the direction of the right Fräsmessumfangs and in the direction of the left Fräsmesserumfangs the majority of Fräsmessklingen are flush next to each other on the right milling head and the left milling head fixed. Viewed in the direction of rotation of the milling heads, cutting blade cutting edges of rear cutter blades protrude in the radial direction beyond the cutting blade cutting edges of front cutter blades with a projection. The supernatant is preferably 0.5 to 3 mm. By this configuration, when milling a double or multiple blade effect can be exploited. The front cutter blade scrapes a relatively large amount of ice when the material is engaged. The immediately following rear cutter blade blades cut a significantly lower ice volume in comparison. The surface of the brittle ice is after cutting out by means of the rear cutter blades in the Compared to the front cutter blades still smoother. As a result of the lateral scraping movement of the cutting blade cutting edge over the ice surface caused by the axial angle of attack, an even smoother milled ice surface is generated.

If the cutting blades have teeth, these are formed on the Fräsmesserschneidkanten the Fräsmessklings. The cutter blades are then preferably arranged such that the teeth of the back and front cutter blades overlap each other in overlapping areas such that the teeth of the front cutter blades completely overlap the teeth of the rear cutter blades, but the rear cutter blades project beyond the front cutter blades in the overhang. The supernatant preferably each forms an exposed edge portion of the rear cutter blades which is not covered by the front cutter blades and which conforms to the contour of the front cutter blades. The teeth of the front and rear cutter blades are preferably contacting each other, i. not offset from each other. The contour and the number of teeth of the front and rear cutter blades are preferably the same.

In a preferred embodiment, the cutting blades are fixed via Messerfixiermittel releasably fixed to the right milling head and the left milling head. On the one hand, it is easy to replace faulty cutting blades. On the other hand, instead of the cutting blades, other cutting blades, such as differently shaped or size-varying cutting blades, or other devices such as brushes, may also be attached to the milling head thus extending the useful radius of the run-in track ice milling unit. The embodiment enables a layered processing of the track inner surfaces. For example, the inrun track Eisfräseinheit in a milling process with a first cutter for "rough milling" ie milling for removing much ice from the rut, for example, with an acceptable smooth rutting surface and in another milling with a second cutter for "fine milling" ie milling for the production of Ruts with excellent smooth rut surface can be used. Furthermore, this embodiment can be set using a single start-track Eisfräseinheit different cutting depths. Examples of knife fixing means are screws and the like. The cutting blades and the milling heads each have suitable recesses for receiving the Messerfixiermittel.

Preferably, the start-track Eisfräseinheit a plurality of cutting blades for replacing the mounted cutting blade, wherein the radial angle of attack and / or the axial angle of attack by the structurally structurally differently designed releasably fixed cutting blade is variable. The one or more angles of attack is or are variable, for example, by variations in thickness of the cutting blades.

Alternatively or additionally, the Messerfixiermittel are designed such that, alternatively or in addition to the cutter blades brushing devices are fixed to the milling heads, with which a milled inrun track can brush out. With the brushing devices, the milled rutting surface surfaces can be further smoothed and / or cleaned with their grooves.

In a preferred embodiment, the milling heads and / or the cutting blades are formed heatable. If the milling head and / or the cutting blades are heated during milling, they will prevent the possibility of ice formation. It is also conceivable that other components of the inrun track Eisfräseinheit are heated, so that the milling heads and / or cutting blades are heated indirectly in this way.

Hereinafter, by way of example, possible embodiments of the inrun track ice milling unit will be described with reference to the figures. The same or similar elements are denoted by the same reference numerals.

Figur 1

eine schematische nicht-maßstabsgerechte Draufsicht auf eine erfindungsgemäße Anlaufspur-Eisfräseinheit;

Figur 2

eine schematische nicht-maßstabsgerechte Draufsicht auf einen der in Fig. 1 gezeigten Fräsköpfe; und

Figur 3

eine schematische nicht-maßstabsgerechte perspektivische Ansicht auf den in Fig. 2 gezeigten Fräskopf.

It shows:

FIG. 1

a schematic non-scale plan view of an inventive inrun Eisfräseinheit;

FIG. 2

a schematic non-scale plan view of one of in Fig. 1 shown milling heads; and

FIG. 3

a schematic non-scale perspective view of the in Fig. 2 shown milling head.

FIG. 1 shows a schematic not-to-scale plan view of an inventive inrun track Eisfräseinheit in an upright installation position. The start-track Eisfräseinheit has a left milling head 1 and a right milling head 1. The right and left milling head 1 processes respectively the right and left ruts (not shown) of the inrun track (not shown), whereby they can be inserted from above into the ruts to be processed, with reference to the operational position of the inrun track. The left milling head 1 and the right milling head 1 each have a bore (not visible) in the center, in which a drive shaft 2 is arranged, which is rotatable about a rotation axis A and which drives the left or right milling head 1 during milling. The right milling head 1 and the left milling head 1 are arranged coaxially on the same drive shaft 2. They are thus rotatable about the common axis of rotation A. The cutting blades 3 of the right milling head 1 and the left milling head 1 are evenly distributed over the right Fräskopfmesserumfang and on the left Fräskopfmesserumfang. On the left milling head 1 and the right milling head 1 are each an equal number of cutting blades 3, purely exemplary three cutter blades 3, arranged along the Fräskopfmesserumfangs. In FIG. 1 are the cutting blades 3 of the left milling head 1 and right milling head 1 viewed along the common axis of rotation A evenly arranged, but preferably not shown here, however, they are offset by an angle of 360 ° divided by twice the number of cutting blades 3 arranged. The cutting blades 3 are each arranged at an axial angle of attack of 3 ° to 16 ° relative to the axis of rotation A. Furthermore, each of the cutting blades 3 is arranged at a radial angle of attack of more than 10 ° to an imaginary radius line between the cutting blade 3 and the axis of rotation A. Each of the cutting blades 3 is by Messerfixiermitteln 4 as For example, screws fixed. The cutting blades 3 each have teeth 33, with which ruts in the track to be machined groove can be generated. The teeth 33 are each formed on a Fräsmesserschneidkante 30 each cutter blade 3, wherein the Fräsmesserschneidkante 30 is shown in dashed lines, if only thought but due to the teeth 33 is not consistently formed physically. The Schneidkantenbereite extends at each cutting blade from right to left or left to right in plan view Fig. 1 , The cutting blades 3 with their respective Fräsmesserschneidkante 30 are arranged relative to a parallel arrangement of the Fräsmesserschneidkante 30 to the rotation axis A at an axial angle of attack a skewed to the axis of rotation A, as shown in the case of a Fräsmessers 3.

FIG. 2 shows a schematic non-scale plan view of one of in Fig. 1 shown milling heads. Shown is a side view of the left or right milling head 1, wherein the drive shaft for clarity is not shown. The left or right milling head 1 further have in the area between adjacent cutting blades 3 an outgoing from the adjacent cutting blades 3, inwardly to the axis of rotation A vaulted towards Fräseisaufnahmeabschnitt 10. The milling ice receiving portions 10 are adapted to receive milled ice during milling.

FIG. 3 shows a schematic non-scale perspective view of the in Fig. 2 shown milling head. In this view, it can be clearly seen that each cutting blade 3 is arranged at an axial angle of attack a of 3 ° to 16 ° relative to the axis of rotation A. This is illustrated by a parallel shifted axis of rotation A *, which attaches to the rear end of the cutter blade 3 and thus the axial angle of attack a between the Fräsmesserschneidkante 30 and the rotation axis A, in contrast to a known from the prior art parallel arrangement of the Fräsmesserschneidkante 30 to the axis of rotation A clarifies. Furthermore, the radial angle of attack of each cutter blade 3 can be seen, the exemplary drawings do not allow reading of angular sizes.

LIST OF REFERENCE NUMBERS

a

axial angle of attack

A

axis of rotation

A *

parallel axis of rotation

1

milling head

10

Fräseisaufnahmeabschnitt

2

drive shaft

3

Removal Bits

30

Fräsmesserschneidkante

33

teeth

4

Messerfixiermittel

Claims (14)

1. An inrun track ice milling unit for a ski jump ice mill having a right-hand milling head (1) and a left-hand milling head (1), each arranged on a drive shaft (2) rotatable about a rotation axis (A) and each having a plurality of milling cutters (3) each formed along a cutting edge width with milling cutter cutting edges (30), wherein the milling cutter cutting edges (30) at a rotation of the left-hand milling head (1) describe a left-hand milling head cutter circumference and at a rotation of the right-hand milling head (1) describe a right-hand milling head cutter circumference and wherein
   on the right-hand milling head (1) along the right-hand milling head cutter circumference and on the left-hand milling head (1) along the left-hand milling head cutter circumference three or more than three milling cutters (3) are mounted,
   characterized in that at least one of the milling cutters (3) with its milling cutter cutting edge (30) is arranged relative to a parallel arrangement of the milling cutter cutting edge (30) to the rotation axis (A) in an axial angle of attack (a) of 1° to 16°, preferably 5° to 14° and particularly preferably 7 ° to 12° in skewed manner to the rotational axis (A).
2. The inrun track ice milling unit according to claim 1, characterized in that each of the milling cutters (3) with its milling cutter cutting edge (30) is arranged in the axial angle of attack (a) of 1° to 16°, preferably 5° to 14 ° and particularly preferably 7° to 12° relative to the axis of rotation (A).
3. The inrun track ice milling unit according to one of claims 1 or 2, characterized in that at least one of the milling cutters (3) is arranged at a radial angle of attack of 5° to 15° to an imaginary radius line between milling cutter cutting edge of the milling cutter (3) and the axis of rotation (A).
4. The inrun track ice milling unit according to claim 3, characterized in that each of the milling cutters (3) is arranged over its cutting edge width at a radial angle of attack of 5° to 15° to an imaginary radius line between milling cutter cutting edge of the milling cutter (3) and the axis of rotation (A).
5. The inrun track ice milling unit according to one of the preceding claims, characterized in that the right-hand milling head (1) and the left-hand milling head (1) have in the area between adjacent milling cutters (3) a milled ice receiving section (10) emanating from the adjacent milling cutters (3) and vaulted inwardly to the axis of rotation (A).
6. The inrun track ice milling unit according to one of the preceding claims, characterized in that the milling cutters (3) of the right-hand milling head (1) are distributed uniformly over the right-hand milling head circumference and the milling cutters (3) of the left-hand milling head (1) are distributed uniformly over the left-hand milling head circumference.
7. The inrun track ice milling unit according to claim 6, characterized in that the right-hand milling head (1) and the left-hand milling head (1) are arranged coaxially on the same drive shaft (2) and are thus rotatable about a common axis of rotation (A).
8. The inrun track ice milling unit according to claim 7, characterized in that the right milling head (1) and the left milling head (1) have the same number of milling cutters (3) which are arranged along the common axis of rotation (A) viewed through an angle of 360° divided by twice the number of milling cutters along the right-hand milling head circumference and along the left-hand milling head circumference offset from each other.
9. The inrun track ice milling unit according to any one of the preceding claims, characterized in that the milling cutters, viewed along the milling cutter cutting edges, have preferably have teeth for forming grooves in the rut inside surface.
10. The inrun track ice milling unit according to one of the preceding claims, characterized in that the milling cutters (3) are each constructed from a plurality of milling cutter blades, wherein viewed in the direction of the right-hand milling cutter circumference and in the direction of the left-hand milling cutter circumference the plurality of milling cutter blades are flushly fixed next to each other on the right milling head (1) and on the left-hand milling head (1) and wherein, viewed in the direction of rotation of the milling heads (1), rear cutter blades with their milling cutter cutting edge (30) protrude in radial direction beyond the milling cutter cutting edges (30) of front cutter blades with a projecting length.
11. The inrun track ice milling unit according to claim 10, characterized in that the projecting length is 0.5 to 3 mm.
12. The inrun track ice milling unit according to one of the preceding claims, characterized in that the milling cutters (3) are detachably fixed via cutter fixing means (4) on the right-hand milling head (1) and on the left-hand milling head (1).
13. The inrun track ice milling unit according to claim 12, characterized in that the ice milling unit has a plurality of milling cutters (3) for exchanging mounted milling cutters (3), wherein the radial angle of attack and / or the axial angle of attack (a) is changeable by fixation of detachably fixed milling cutters (3) formed in structurally different manner.
14. The inrun track ice milling unit according to one of claims 12 or 13, characterized in that the cutter fixing means (4) are designed such that, alternatively or in addition to the milling cutters (3), brushing devices can be fixed on the milling heads (1), with which a milled inrun track can be brushed out.

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