FI77074C - Shock absorbing layer for trot and canter tracks - Google Patents

Description

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The present invention relates to an impact-damping layer for trotting and galloping tracks consisting of wood fibers. This layer 5 can also be used for other purposes / where shock absorption is desirable, such as on sports tracks, tracks, walking and cycling roads, etc.

On treadmills or gallop tracks, it is desirable that this have a shock absorbing effect to save the horse's legs.

10 It is therefore desirable to provide a track in which the track frame provides optimal flexibility. That is, the correct relationship between the shock absorption and the shape of the surface, depending on the purpose of the track. This is important to prevent injury to the horses. In addition, it is an important factor in training horses that have been (or are) injured.

In addition, the spring layer must be able to consist of natural gravel or crushed aggregate that satisfies the requirements of the flow layer and in which the grain size distribution is such that it can be applied so that the granules 20 form an inverted filter. This ensures cheap and renewable materials, adequate water permeability and easy and cheap mechanical treatment.

The shock-absorbing layer must consist of a material which is relatively easy to obtain, preferably obtained by pretreatment from otherwise little useful natural resources, and which has sufficient mechanical and chemical resistance.

The shock-absorbing layer must be easily permeable to water and must be able to act as a dewatering layer 30 in addition to the shock-absorbing properties. In addition, it must be able to retain moisture for a certain period of time.

Normal temperature fluctuations must have the least possible effect on the damping. The shock-absorbing layer must improve the winter properties of the upper layer.

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It must be possible to operate and maintain the track without having to pay particular attention to the shock-absorbing layer.

No other layer in the track body shall become more expensive. The load-sharing and dewatering properties of the shock-absorbing layer must be able to alleviate the requirements for substrate thicknesses and dewatering properties.

Variations in the properties of the substrate and the tread must be easily adjustable by adjusting the composition / thickness of the shock-absorbing layer.

Previously known attempts to satisfy any of the above requirements have not proved to be sufficient and none of the solutions patented to date, e.g. disclosed in SE Patent No. 15,373,400 or No. 307,967, have proved suitable.

SE Patent No. 373,400 describes a layer in which a shock absorbing layer in the bark has been tested. However, this decays soon and does not withstand mechanical stress well, it absorbs water and is also almost waterproof. The usability is low because the layer often needs to be replaced (it rots) and the desired shock-absorbing effect disappears completely during the frost season. In addition, the upper tread becomes wet during rain.

Tracks built from a mixture of aggregate, conifers and wood debris (twigs, etc.) from murs-25 Street have also been tried. This does not give a satisfactory surface. The surface is difficult to treat, the wear deteriorates the layer quickly (internal friction of the mixture) and the layer is therefore technically and economically poor.

SE Patent No. 307,967 describes a layer using foamed or sealed plastic cells as a shock absorbing medium. However, this is very expensive and the layer cannot be easily stabilized, but requires an outer layer bonded with bitumen or plastic. In practice, 35 it has proven to be of little, if any, suitability for racetracks.

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Birch birch tracks bound with bitumen have also been tried, but this has proven to be expensive and is only suitable for small sites. In addition, the layer lets water through poorly and causes surface problems during the rain 5 and thus causes moisture-softened tracks.

The top layer (outer layer) must be bitumen-bound asbestos or glass fiber. This surface layer is therefore not suitable for track and track tracks.

The present invention provides a shock absorbing layer for trotting and racing tracks, characterized in that the layer is separated from the upper running layer and possibly the lower layers by a nonwoven fabric.

This layer has thus provided a track in which the above requirements have been met and in which these do not make the total price of the track higher.

Other features of the invention will be apparent from the subclaims.

The invention will now be described in more detail with reference to the drawings, in which: Figure 1 shows a cross-sectional view of a shock absorbing track according to the invention; and Figure 2 shows a view of the treadline boundary curve.

The tread and gall layer according to the invention consists of a tread 1, which is a natural gravel or crushed mass with a thickness of 8-20 cm, and the tread 1 is placed on top in the form of an inverted filter, the grain size being 0-4 mm at the top 4-6 cm, and then with a grain size of 4-8 down to the desired depth.

Figure 2 shows the grain size distribution of the tread. . curve.

Under this running layer, a nonwoven fabric 2 is placed to separate the gravel layer from the shock absorbing layer 3, which consists of machined wood fibers.

35 Wood fiber material is required to have an even distribution of fibers 4 77074 with a length of 0-70 mmf with a width of 0-40 mm and a thickness of 0-10 mm. This is achieved by chipping and then mechanical defibering. Wood can be new or waste from forest use or the wood industry.

5 Wood fibers are made from hardwood to which fungicides and bactericides may be added, or from softer wood that is impregnated. The required thickness of the wood fiber layer 3 depends on the quality of the wood and also on the structure of the track, but normally it is in the range of 5-20 cm. 10 On special tracks for training, riding and damage repair, the wood fiber layer can be made thicker, up to 30-40 cm thick. The wood fiber layer is also protected against the contaminating effect of other pulps by a nonwoven fabric 4 below, but this can be omitted when the soil is particularly good. Beneath this nonwoven fabric 4 is an ordinary carrier / drying layer 5 which is sufficiently thick, and below this is an ordinary ground 6.