BACKGROUND OF THE INVENTION The problem of connecting a Christmas tree to its stand, to fasten the two safely to each other and to provide the Christmas tree with the correct vertical orientation has been a challenge to which many solutions have been provided.

In particularly one type of Christmas tree stand involves a cumbersome method of fastening the tree to it The stand is made from a piece of wood, such as a length of a tree trunk that has been halved in the longitudinal direction, and in which a hole is drilled for accommodating the lower end of the trunk of the Christmas tree. The end of the Christmas tree trunk is given a tapered shape manually or at least partly manually, where after it is inserted into the hole in the stand. In case the Christmas tree trunk does not fit into the hole or the Christmas tree is not in the correct vertical orientation, i. e. is out of plumb, the end of the Christmas tree trunk has to be removed from the stand and reshaped. The process is thus very labour-intensive.

It is therefore an object of the present invention to provide an improved manner of connecting a Christmas tree to a Christmas tree stand.

This is provided by the present invention, in which a connecting piece is fastened to the cut surface of the trunk of the Christmas tree, the connecting piece having a convex substantially spherical surface part of a first diameter, and the connecting piece is inserted into an opening of a Christmas tree stand preferably made from a resilient material, wherein the opening has a substantially circular cross section of a

second diameter smaller than the first diameter. The resiliency of the material, preferably wood, but rubber, plastics materials etc. may also be applied, allows the connecting piece with a larger diameter to be entered into the opening at the application of a force pushing the Christmas tree longitudinally towards the opening.

The strain of the material of the Christmas tree stand and/or the connecting piece due to the deformation caused by the connecting piece provides an elastic holding force that locks the connecting piece and the stand together and preserves a vertical orientation of the Christmas tree. However, the vertical orientation of the tree may be adjusted manually by grabbing an upper end of the tree and pull or push it in the correct direction, causing the connecting piece to change orientation within the opening in the stand.

The advantages of the present invention are that the Christmas tree is connected safely to the stand, that the connection is obtained easily by fastening the connecting piece, e. g. by means of screws, to the cut surface of the trunk without the need to change the shape of the trunk or even to correct a slandered cut surface, the orientation of the tree may be corrected in a simple manner and the full length of the tree as felled may be used, because it is not necessary to enter a part of the trunk into the stand, thereby saving about 10 centimetre of each Christmas tree. These and other advantages will be apparent from the following description.

Various types of Christmas tree stands using cooperating spherical surfaces are well known in the art and are disclosed e. g. in DE 198 55 705, US 6,010, 108, US 5,398, 444, US 5,577, 701 and in EP 0 943 273. The use of spherical connecting pieces is in particular disclosed in DK 1999 00353 U3 and US 5,938, 167, but none of the disclosed Christmas tree stands provide a solution to the above problem.

BRIEF DESCRIPTION OF THE INVENTION The present invention relates in a first aspect thereof to a method for fastening a Christmas tree to a Christmas tree stand, comprising the steps of

fastening, e. g. by screws, nails or glue, a connecting piece to the cut surface of the trunk of the Christmas tree, the connecting piece having a convex substantially spherical surface part of a first diameter, and inserting the connecting piece into an opening of a Christmas tree stand, the opening having a substantially circular cross section of a second diameter smaller than the first diameter, wherein resiliency between the connecting piece and the Christmas tree stand allow said insertion. The resiliency is preferably provided by a resilient material used for the Christmas tree stand, in particular that the Christmas tree stand comprises a wooden block wherein said opening is provided. The method may further comprise the step of adjusting the vertical orientation of the Christmas tree.

The second diameter is in a preferred embodiment within 0.2 to 3 millimetres, preferably within 0.35 to 1. 8 millimetres smaller than the first diameter. In the disclosed embodiments, the second diameters are within 0.5 to 1 millimetres smaller that the first diameter, i. e. 0.5, 0.8 and 1 millimetre smaller, respectively.

The standard cross-sectional sizes of the openings in the Christmas tree stands are 40,50 and 60 millimetres, and the outer diameter of the convex spherical surface of the connecting piece according to the present invention is consequently preferably within a range selected from the group consisting of 40.2 to 43 millimetres, 50. 2 to 53 millimetres and 60.2 to 63 millimetres, most preferred within a range selected from the group consisting of 40. 35 to 41. 8 millimetres, 50.35 to 51.8 millimetres and 60.35 to 61.8 millimetres.

The present invention relates in a second aspect to an assembly of a Christmas tree stand and a Christmas tree as may be obtained by the disclosed method.

In a third aspect, the present invention relates to a connecting piece for connecting a Christmas tree to a Christmas tree stand, the piece having a substantially plane surface with at least one through-hole provided therein and a convex substantially

spherical surface extending from said plane surface. The plane surface is suitable for abutting contact with the cut surface of the Christmas tree trunk and has preferably an average diameter of 24 to 60 millimetres, most preferred of 30-50 millimetres, and the at least one through-hole is suitable for passing a screw or nail to fastened the connecting piece to the Christmas tree trunk.

The connecting piece is preferably provided with an opening on the side opposite to the plane surface and extending towards the plane surface through most of the inner part of the piece, the opening having a cross-sectional area of between 0.3 and 0.7 of the largest cross-sectional area of the piece. Thereby, access to the through hole or holes may be made easier and a resiliency of the outer walls of the piece forming the spherical surface may be provided. The opening extents preferably substantially normal to said plane surface. The cross-sectional area discussed is taken substantially parallel to the plane surface.

BRIEF DESCRIPTION OF THE DRAWING Embodiments of the invention are disclosed below with reference to the enclosed drawing of which Fig. 1 shows three different Christmas tree stands that are suitable for use with the present invention, Fig. 2 shows a vertical section of a Christmas tree connected to a Christmas tree stand by means of a connecting piece, Fig. 3 shows a vertical section of a Christmas tree connected to a Christmas tree stand by means of a connecting piece, in which the cut surface of the Christmas tree trunk is slandered, Fig. 4 shows a working drawing of a connecting piece for a 40-millimetre opening,

Fig. 5 shows a working drawing of a connecting piece for a 50-millimetre opening, and Fig. 6 shows a working drawing of a connecting piece for a 60-millimetre opening.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE PRESENT INVENTION Fig. 1 shows three different Christmas tree stands 1 having an opening 2 provided therein of a substantially circular cross-sectional shape. The opening 2 is suitable for receiving the lower end of the trunk 3 of a Christmas tree, i. e. normally a fir tree that is 0.75 to 2.5 meters high. Standard cross-sectional diameters of the openings 2 are 40,50 and 60 millimetres. Fig. 1A shows a stand 1 made from a length of a tree trunk that has been halved in the longitudinal direction, and in which a hole 2 is drilled for the lower end of the trunk 3 of the Christmas tree. Fig. 1B shows a stand 1 made from a length of a tree trunk in which a hole 2 is drilled in an end surface. Fig.

1 C shows a more elaborated stand 1 made from wood and intended for repeated use, whereas the stands 1 shown in Figs. 1A and 1B are disposable stands 1 intended for a single use only.

The connecting piece 4 is fastened by means of screws 5 onto the cut surface 6 of the trunk 3 as shown in Figs. 2 and 3. The connecting piece 4 has an upper substantially flat surface 7 matching the cut surface 6 of the trunk 3. The connecting piece 4 is pressed into the opening 2 which is of a slightly smaller cross-sectional diameter, so that the material of the stand 1 and/or the connecting piece 4 is strained and due to the deformation caused by the connecting piece provides an elastic holding force that locks the connecting piece and the stand together and preserves a vertical orientation of the Christmas tree. In Fig. 3, a situation is shown where the cut surface 6 of the trunk 3 is slandered, i. e. that it is not perpendicular to the longitudinal direction of the Christmas tree. The connecting piece 4 is as in Fig. 2 fastened to the cut surface 6 by means of screws, and the connecting piece 4 is inserted into the opening 2. Due to

the spherical surface part of the connecting piece 4, the Christmas tree may in this situation also be arranged to extend vertically from the stand 1.

In Figs. 4,5 and 6, working drawings of connecting pieces 4 for openings of 40,50 and 60-millimetres of cross-sectional diameter, respectively, are shown. The outer diameters of the connecting pieces are in this embodiment selected to be 40.8, 51 and 60.5 millimetres, respectively. All measures on the drawings are given in millimetres. All the shown connecting pieces 4 have an opening 8 provided on the side opposite to the plane surface 7 and extending towards the plane surface 7 and perpendicularly to it through most of the inner part of the piece 4. The cross-sectional area of the opening 8 is preferably sufficiently large as compared to the largest cross- sectional area of the piece 4, in the shown examples 0.52, 0.56 and 0.45, respectively, to provide the walls of the piece 4 with some resiliency. An area ratio of between 0.3 and 0.7 is preferred. The material of the connecting piece 4 may be any suitable material, preferably a high-density polyethylene (HDPE).