INTRODUCTION

The present invention relates to a blow plane for cutting the horn wall of a hooved or cloven-hooved animal, e.g. horses or cows. More specifically, the invention relates to a blow plane for defined cut-out of a horn wall of a hooved or cloven-hooved animal, wherein said blow plane comprises a frame and a knife fastened to the frame, wherein said knife extends in a longitudinal direction to enable it to cut the horn wall by moving the frame relative to the horn wall in a longitudinal direction, wherein knife and frame define a width and a height of the cut-out in which width as well as height are dimensions transversing the longitudinal direction.

The invention further relates to a hoof or cloven-hoof fitting and a set consisting of the blow plane and an associated fitting, wherein said blow plane is adapted to match the cut-out to the fitting. In the following, the invention will be described on the basis of hooved animals. However, the invention could also be used for cloven-hooved animals, e.g. cows.

BACKGROUND OF THE INVENTION

From the time when the horse was tamed and domesticated by man, hoof care has been a necessity. Different means have been used in the attempt to keep the hoofs as healthy, smooth and durable as possible. Through proper hoof care you can, to a high degree, influence the stance and movement of the horse and thereby its performance and durability.

For thousands of years, various forms of horse shoes have been used to protect the hoof or the cloven hoof against wear. A horse shoe is fastened to the bottom surface of the hoof, e.g. by means of horse shoe nails or glue. A common trait for all forms of known horse shoes is their harmful effects, inter alia that the known horse shoes lock the hoof mechanism, thereby wholly or partly disabling the hoof's own shock-absorbing effect. Furthermore, in traditional horse shoes vibrations often occur similar to the vibrations in a tuning fork. When these oscillations interfere, it can be extremely harmful for the animal.

WO 2009/143844 shows a fitting comprising a blade and a shank which can fasten the blade to a hoof. It has been found to be advantageous if the fitting shown is countersunk into the hoof in such a way that the blade is substantially level with the underside of the hoof wall.

The present invention relates to a blow plane which can be used to remove part of the horn wall and thus be used in connection with shoeing using fittings which are to be countersunk into the hoof, for example fittings as shown in

WO 2009/143844.

Planes are available in multiple configurations for different purposes, primarily for wood processing, however. The known planes are generally not suited for the processing of hoofs, and typically they do not help the user by providing a specific cutting shape well-suited for sinking fittings into the hoof. Generally, known planes are not suitable for operation by blows and thus they cannot be defined as planes.

To better understand the problems of hoofs and cloven-hoofs, reference is made to the book "Moderne hovpleje" (Modern Hoof Care) by H. H. Smedegaard, Jordbrugsforlaget, ISBN-13 9788774323877. Briefly, the problem is that the underside of the hoof - i.e. the side of the hoof on which the horse carries all its weight - comprises an outer area of horn - among those skilled in the art referred to as the horn wall. Towards the centre of the underside of the hoof, the horn wall is followed by an area called "the brown line". The horn wall and the brown line are separated by a "white line". Further inwards towards the centre is the pododerm, which constitutes the innermost part of the hoof. The horn wall does not contain nerves meaning that shoeing as well as trimming thereof is not associated with pain to the animal. However, the brown line constitutes the boundary between horn wall and the pododerm, which contains nerves. When shoeing a horse, it is consequently ensured that the shank is inserted into an area between the middle of the horn wall lower edge and inwards across the white and brown lines to an innermost insertion point at a safe distance to the pododerm. In the following, the term "safe line" refers to the boundary to the pododerm to which the shank may be inserted without the risk of damaging the hoof or cloven-hoof or causing the animal pain. A skilled farrier will be able to determine the safe line of a specific animal. When the shank is inserted between the centre of the horn wall lower edge and the safe line, the shank can transfer forces to the horn capsule of the hooved or cloven- hooved animal with very little risk or no risk at all of the horn capsule cracking or in any other way being damaged. It is an objective of the invention to provide a blow plane providing better support when cutting out a hoof for the countersinking of a fitting into said hoof.

DISCLOSURE OF THE INVENTION:

With a view to inter alia ensuring the proper cut-out of a hoof, the invention provides a blow plane characterised in that it comprises a lever that, when contacting the horn wall during the use of the blow plane, defines the cut-out to have a predefined length wherein the length is a longitudinal dimension.

Due to the length definition provided by the lever, a measured cut-out in a defined area of the hoof or the cloven-hoof can be performed, and the horn wall may thus be cut without damaging the pododerm. At the same time, the blow plane may ensure that the cut-out is dimensioned and shaped specifically for the countersinking of a hoof fitting with a particular configuration. The advantage of this is that the fitting may be supported along its periphery by the inner edge of the cut-out, and the displacement or damaging of the shoeing may thus be avoided.

The term "blow plane" as used herein is to be understood as a plane that may provide a cut-out using blows, e.g. with a hammer, on an edge of the plane without altering themachining characteristics of the plane. This means that the plane may be operated using blows without displacing the knife relative to the frame.

Consequently, the knife must be securely fastened to the frame, e.g. by the frame and the knife being cast in one piece. In addition, the knife may be formed of steel, which is known to be suitable for cutting, e.g. types of steel known for the manufacture of knives.

The blow plane may be designed for use on a particular animal by being dimensioned to make the predefined length correspond to a realistic total size of the horn wall and the brown line measured perpendicularly inwards from the outer edge of the hoof or cloven-hoof underside. To this end, the blow plane may form part of a series of planes of the same geometry but with different dimensions adapted to animals having hooves of different sizes.

For example, the lever may be designed to shape the cut-out to define a total cut-out length of between 1 and 14 millimetres. In one embodiment, the lever is designed with an oblique edge to give the cutout a shape which in the longitudinal direction of said cut-out defines a first section of uniform height and another section with descending height. This way, the blow plane may be used to remove a piece of uniform thickness from the horn wall and to continue the cut-out from the horn wall across the white line and into the brown line, wherein the thickness of the final part of the cut-out crossing the white line has a decreasing thickness.

The lever may be designed to define the length of the first section to a horn wall thickness which is realistic for the animal, and to define the length of the second section to a brown line thickness which is realistic for the animal. In this respect, both thicknesses are measured perpendicularly inwards from the outer edge of the hoof or cloven hoof underside.

The lever may be designed to give the first section and the second section of the cut-out longitudinal direction completely individual lengths. That is to say that the first section may be 2, 3, 4, 5, 6, 7, 8, 9 or 10 times bigger than the other section. However, it may be advantageous if both sections are equally long, or if the difference in length is no more than 30 percent.

The lever may be designed to give one of the two sections a length of between 0.1 and 2 centimetres in the cut-out longitudinal direction. This range would be appropriate for most hooved and cloven-hooved animals.

The invention also relates to a fitting for countersunk fastening in the horn wall of a hooved or cloven-hooved animal, said fitting forming a plate including an underside that can abut the horn wall lower edge, and an upper side suitable as plantar surface for the animal, wherein the plate is designed to secure the fitting to the horn wall using at least a fastening element which is inserted into the horn wall, characterised in that the plate volume exceeds twice the volume of the fastening element part that is designed to be inserted into the horn wall.

The fastening element is a separate element and could e.g. be a fitting as shown in WO2009/143844 or any other fitting including a shank suitable for insertion into a horn wall and termination to secure the plate, e.g. in the form of a crown, a knob or a blade.

The plate may form a passage, i.e. for example a through hole, for each fastening element which may thereby by inserted into the horn wall through the passage. The passage may thus be designed in relation to the fastening element to prevent rotation of the plate relative to the fastening element. In practice, this can be achieved using a non-rotational-symmetrical cross-sectional shape of hole and fastening element. The shank must be suitable for insertion into the horn wall, i.e. it should be of a shape ensuring that the shank is not worked into the pododerm during insertion, and that it is a type capable of being inserted into a horn wall without deforming or at least without collapsing. The shank may be designed so that the shank geometry influences the path of the shank trough the horn wall to be curved through the horn wall. To that end the shank may suitably comprise two side surfaces connected with two edge surfaces, one side surface forming an oblique termination, and the other side surface forming a straight termination. When being inserted, the shank will curve in a direction away from the obliquely terminated side surface and thus away from the pododerm by appropriate mounting of the fitting in relation to the hoof. Moreover, the edge surfaces may run towards each other towards the termination, resulting in a tapered termination.

The transition between the two side surfaces and the two edge surfaces may suitably be rounded or bevelled, which may ensure a more gentle insertion into the horn wall, thereby reducing the risk of undue damage to the area between the horn wall and the pododerm. Furthermore, the shank may have the same shape as the shank for a horse shoe nail, wherein the shank has a widest side surface close to the top and the side surface narrows towards the tapered shank end, enabling it to be inserted into the horn wall, such that the shank causes the least possible damage.

Furthermore, the invention relates to a fitting set comprising a blow plane as already described and a fitting adapted for countersunk fastening to the hoof or the cloven-hoof, characterised in that the lever is designed to define the cut-out so that it is shaped to fit the fitting.

Thus, the blow plane shapes the cut-out specifically to fit the associated fitting. This means that the size of the knife and the lever is adapted to the fitting.

Furthermore, the invention relates to a method for fastening a fitting to the horn wall of a hoof or a cloven-hoof, said method comprising the formation of a cut- out shaped to fit the shape of the fitting using a blow plane as described above and subsequently the fastening of the fitting using a fastening element which is inserted into the horn wall.

DETAILED REVIEW OF AN EMBODIMENT The invention will be described further below referring to the drawings, wherein: Figures 1 and 2 illustrate a horse's hoof;

Figures 3, 4 and 5 illustrate a blow plane according to the invention; Figures 6 and 7 illustrate enlarged sections of the blow plane; Figures 8 and 9 illustrate knife angles; Figures 10 and 11 illustrate a cut-out with a first and second section; and Figure 12 illustrates a fitting 2 according to the invention. Figure 1 shows a hoof 1 with a fitting 2 which is to be countersunk.

In Figure 2, the dotted line 3 shows a centre line from which the distance to the outer edge of the horn capsule underside and to the inner edge of the horn capsule, i.e. the brown line, is the same. The point of insertion of the shank of the fitting should be between this centre line and the safe line.

As shown in figures 1 and 2, the hoof 1 comprises a horn wall with a fitting 2. The blow plane according to the invention provides a cut-out 3 - see Figures 10 and 11. The cut-out is made to countersink the fitting 2 into the horn wall so that horn wall and fitting combined will form an approximately plane underside or an underside wherein the fitting is located slightly below the natural tread level of the horn wall. Figures 3, 4 and 5 show the blow plane 4, which includes a frame 5 and a knife 6 fastened to the frame. The knife has a tapered end 7 pointing in a longitudinal direction symbolised by the arrow 8, cf. Figure 5. At the opposite end, the blow plane rear end is located, which is suited for receiving blows from e.g. a mallet or a hammer.

By moving the blow plane in the longitudinal direction, the knife may thus cut away part of the horn wall.

Figures 6 and 7 show enlarged sections of the plane. The width of the knife, symbolised by arrow 9, cf. Figure 6, and the height of the knife, symbolised by arrow 10, define a width and a height of the cut-out - i.e. width as well as height are transverse dimensions relative to the longitudinal direction symbolised by arrow 8.

The blow plane comprises a lever 11, which in contact with the horn wall during use of the blow plane defines the cut-out so that it is made with a predefined length - i.e. the lever 11 defines the longitudinal dimension of the cut-out.

The lever is obliquely adapted, symbolised by angle 12, causing the cut-out to define a first longitudinal section of uniform height and a second section with a descending height - see Figures 10 and 11, which show the actual cut-out. The first section is defined during the movement of the knife into the horn wall before the lever 11 contacts the hoof.

In the embodiment shown, both sections are approximately of equal length.

The shown blow plane is manufactured in 2 parts by placing a metal knife in an injection moulding tool and subsequently moulding the frame and lever in one piece, e.g. in plastic metal, carbon, a mix of these or any other blow-resistant, preferably blow-transforming, material.

The knife has a series of holes of which one hole 13 is visible. The holes secure the knife in the plastic frame and prevent rearwards displacement. Thus, change in the blow plane geometry during blows as well as erroneous cut-out of the hoof are prevented.

The blow plane has 2 open slots 14, 15 formed in the leading edge of the plane.

The long slot 15 is used to support the shank of a fitting during the fastening of the fitting to the hoof.

The short slot 14 extends longitudinally and indicates the centre of the knife. Thus, during the cut-out of the horn wall, the slot 14 serves as a sight.

Subsequently, the short slot 14 may be used to support a short shank, e.g.

when the final part of the shank is tapped into the hoof. In that way, bending of the shank may be avoided.

Figures 8 and 9 illustrate diagrammatically how to choose to angle the sides of the knife to prevent the cut-out horn wall piece from getting caught between the side walls of the knife. As seen, the knife 6 has three sides 16, 17, 18. The shown angles α and β prevent squeezing and facilitate removal of the cut-out piece from the blow plane. The drawing is dramatically distorted as α in the order of 75-89 degrees and β in the order of 1-10 degrees would be appropriate.

Figure 10 is a stylistic section through a horse's hoof. This section clearly shows that the cut-out 19 includes a first section 20 and a second section 21, the first section having a constant height and the second section having a descending height to finish the cut-out completely at the rear edge 22 of the brown line, i.e. before the pododerm 23.

Figure 11 shows the underside 24 of the horn wall and the underside 25 of the brown line - the dotted line is drawn to symbolise the transition between the horn wall and the brown line and is often termed "the white line". The cut-out length is indicated by the arrow 16.

Figure 12 illustrates a fitting 27 for countersunk fastening in the horn wall of hooved or cloven-hooved animals. The fitting comprises two separate parts 28, 29. The part 28 is a plate with a through hole 30, and the part 29 is a shank which can secure the plate 20 to the underside of the hoof. The shank could e.g. be similar to a normal horse shoe nail.

As seen, the shank does not have a circular cross-section, and the cross-section shape matches the through hole. Thus, rotation of the plate relative to the fastening element is prevented.