WO1988000112A1

WO1988000112A1 - Axe

Info

Publication number: WO1988000112A1
Application number: PCT/SE1987/000309
Authority: WO
Inventors: Sören HENRIKSSON
Original assignee: Holmens Bruk Ab
Priority date: 1986-06-30
Filing date: 1987-06-30
Publication date: 1988-01-14
Also published as: DK103988A; SE8602912D0; SE457511B; DK103988D0; AU7589787A; SE8602912L

Abstract

An axe that preferably is to be used for the splitting of wood. The axe is intended to act in a plane of movement (1), and it includes a bit (2) located in said plane of movement, a head (3) located opposite to the bit, a forward side surface (4) and a backward side surface (5) and blade sides (6, 7) located on each side of the plane of movement (1). On each one of the blade surfaces there is a raised portion (8, 9). The raised portions (8, 9) are placed diagonally in respect to each other, the axe thus being given a shape that is not specularly symmetrical.

Description

Axe

The present invention relates to an axe in accordance with the one defined in the introductory clause of claim 1.

Axes of this kind have been known for a very long time and have been developed from the rounded shape of the stone axe to axes with comparatively thin blades, which is advantageous when the axe is used for carpentry or for delimbing. The axes used for splitting wood have a more rounded shape in order to increase the splitting effect when the axe is rammed into the wood, since the axe on one hand is given a greater splitting effect and, on the other hand, the friction-causing surface of the axe engaging the wood is decreased.

Axes used today are symmetrically shaped in respect to the plane of movement wherein the axes act.

A type of axe has also lately been developed that is provided with small levers that are folded out when the axe strikes the wood and in this way aid in splitting the wood.

One aim of the present invention is to provide an axe having a very great splitting effect.

Another aim is to provide an axe that engages the wood with a very small friction-causing surface.

A third aim is to achieve this axe in a simple and comparatively cheap way.

These aims are achieved with an axe having the features defined in the characterizing clause of claim 1. The axe according to the invention thus is given a shape that is not specularly symmetrical in respect of the plane of movement. This has the effect that the axe will give an additional twisting force in respect to the plane of movement, apart from the splitting force being perpendicular to the plane of movement, which will give a very great cleaving effect in comparison to symmetrical axes. By means of the shape according to the invention the surface of the blade that contacts the wood will be very small which results in a low friction between axe and wood. The axe according to the invention will be explained more closely in the following description of a preferred embodiment taken in conjunction with the attached drawings and given only as an example.

Fig. 1 shows a side view of an axe according^'to the invention. Fig. 2 shows a front view of the axe according to the invention. Fig. 3 shows a section along the line III— III in Fig. 1. Fig. 4 shows a view seen from above of an axe according to the invention. Fig. 5 shows a section through the axe according to the Invention.

Fig. 6 shows a section through a conventional symmetrical axe.

Fig. 7 shows a section through an alternative embodiment of the axe according to the invention.

Fig. 8 shows a view seen from above of the alternative embodi¬ ment in Fig. 7.

Fig. 9 shows a section through another alternative embodiment of the axe according to the invention.

Fig. 10 shows a view seen from above of the alternative embodi¬ ment in Fig. 9.

The embodiment of an axe according to the invention shown in Figs. 1-4 acts in a plane of a movement 1 and it includes a bit 2, a head 3, a forward and a backward side surface 4 arid 5 as well as two blade sides 6 and

7. Each blade side includes a raised portion 8 and 9 and these raised portions

8, 9 have a triangular shape seen from the side, the tip of the triangle terminating in, or in the direction of, the point of intersection between the bit 2 and one of the side surfaces 4 or 5. The upper base of the triangle is substantially parallel to the head 3 and can extend all the way up to the head or be displaced downwards to some extent in respect to the head. The raised portions 8, 9 are placed diagonally on each side of the plane of movement, i.e. the one triangularly shaped raised portion 8 is located adjacent to the side surface 5 with its one triangle side, and the other triangularly shaped raised portion 9 is located with its one triangle side adjacent to the side surface 4. The other triangle sides of the triangular raised portions 8, 9 extend from the tip of the triangle to, or in direction towards, the point of intersection between the head and the respective side surface. As can be seen in Fig. 2 the raised portion is softly decreasing in the direction towards the bit 2. The raised portion can also be softly decreasing in the direction towards the head 3, the raised portion having its highest point in the vicinity of the middle of the axe.

In the embodiment shown each of the two triangularly shaped raised portions 8, 9 thus will have the other triangularly shaped raised portion located opposite on the other blade side in the upper part of the axe, and the axe thus will be comparatively thick in this end. Further there will not be any raised portion on the blade sides in the lower part of the axe close to the bit 2, and the axe will therefore be comparatively thin in this part which facilitates the penetration of the axe into the wood. Since the raised portions are located above the contour of the profile of the axe, only the raised portions will be in contact with and press against the wood, in turn pressing against the raised portions with a great force. This is illustrate^'d in Fig. 5 showing how the axe according to the invention comes into contact with the wood when the axe has been rammed a distance into the wood. As can be seen the axe according to the invention only will come into contact in places shaped as points. In Fig. 6 as a comparison it is shown how a conventional symmetrical axe comes into contact with the wood and it can be seen that the surface of contact with the wood is considerably larger than the surface of contact in the axe according to the invention.

Since the raised portions start from the bit 2 on each side of the axe and meet further up in the middle of the axe, the axe will be screwed through the wood, especially in twisted wood, wherein the fibers have grown in a way that they are not oriented parallel to each other and are twisted in the wood.

Figs. 7 and 8 show an alternative embodiment of the axe according to the invention, wherein the raised portions have a smaller extent along the blade sides. Each one of the raised portions extend herein directly from or from the vicinity of the point of intersection between bit and one side surface diagonally to or close to the point of intersection between head and the other side surface.

Still another embodiment is shown in Figs. 9 and 10 wherein each one of the raised portions extend directly or from vicinity of the point of intersection between bit and one side surface along this side surface to or close to the point of intersection between this side edge and the head. The raised portion can possibly also be displaced a comparatively small distance from this side surface.

Claims

1. Axe, particularly for splitting wood, including a blade with a bit (2), an axe head (3) opposite to the bit, a forward side surface (4), a backward side surface (5), and splitting blade surfaces (6, 7), characterized in that the blade surfaces (6, 7) are provided with raised portions (8, 9) extending substantially from the axe head towards the ends of the bit, the distance between the sides of the respective raised portions (8, 9), that are close to the ends of the bit and initially strike the wood, and the respective side surface (4, 5) opposite to said ends, decreasing continously in the direction towards the axe head (3).

2. Axe according to claim 1, characterized in that the raised portions (8, 9) have a triangular shape, the bases of the triangles being substantially parallel to the head of the axe and the tips of the triangles terminating in or in the direction of the point of intersection between the bit (2) and the side surfaces (4, 5).

3. Axe according to claims 1 or 2, characterized in that the thickness of the raised portions continously increases in the direction towards the axe head (3).