The invention relates to elongate construction elements composed of a number of separate parts or profiles, which construction elements can preferably be used for vehicle frames.
Known types of elongate construction element are, for example, beams with I, L and U-shaped cross-sectional profiles. It is characteristic of such beams that they are as a rule manufactured by means of rolling, each section of the parts which form the cross section having the same dimension or thickness along the entire length of the beam. In many applications, a beam does not have to have the same strength, for example flexural rigidity, along its entire length. As the beam has to be dimensioned according to the maximum load to which it will be subjected, it may be overdimensioned along large parts of its length. This is true of, for example, beams included in a vehicle frame.
One problem with overdimensioned beams is that they have a correspondingly great weight. A conventional way of solving this problem has been to cut away parts of the beam for the purpose of saving weight. For beams with I and U-shaped cross-sections, selected parts of the web can be cut away from the parts of the beam which are subjected to relatively low load. However, this method produces a somewhat limited result and moreover is relatively complicated to carry out because it requires very advanced equipment in order to cut out the parts with sufficient precision. Furthermore, a beam dimensioned for the maximum load still has to be used as the starting material, which results in a correspondingly high purchase price. A mistake in the machining of the beam leads in most cases to the whole beam having to be discarded.
One problem the invention aims to solve is to allow the manufacture of beams which are correctly dimensioned along their entire length. Another problem solved by the invention is the use of a lighter and less expensive starting material.
In an exemplary embodiment, the invention relates to an elongate construction element comprising a first elongate profile with a first section located in a first plane and a second section located in a second plane different from the first plane and a second elongate profile with a first section located in a first plane and a second section located in a second plane different from the first plane, and at least one third profile.
According to a preferred embodiment, the respective first sections of the first and the second profile are located in essentially the same plane, and the third profile constitutes a web which is fixed to and interconnects the first sections along at least a part of the extent of the construction element. Examples of suitable profiles for this purpose are, for example, T or L profiles. The first sections suitably consist of the upright in a T profile or a leg in an L profile. In the text below, that section of the first and second profiles located in the same plane in order to be interconnected by the third profile is throughout called a “first section”. The third profile, or the web, which connects the first and the second profile is preferably a plate or a plane I profile.
According to one embodiment, the web extends along the entire length of the construction element and has a thickness which is smaller than the thickness of the two first sections. However, the thickness is determined in the first place by calculations which determine the loads to which the construction element may be subjected, which calculations are also dependent on, for example, the number, the positioning and the total extent of all the component webs. The thickness can therefore be constant for all the webs or vary from web to web, depending on the calculations.
According to another embodiment, the web consists of a number of sections positioned at intermittent or regular spacings along the entire length of the construction element. These sections can be positioned on one and the same side of the first sections. The side selected is determined by strength calculations which take account of how the construction element is loaded.
According to another embodiment, the sections of the web can be positioned on different sides of the first sections. Depending on how the construction element is loaded, one or more of the sections of the web can be positioned on opposite sides of the first sections.
According to an alternative embodiment, at least one of the sections of the web can be bent and provided with opposite cutouts corresponding to the thickness of the first sections, the section then being capable of running along both sides of the first sections. A first and a last part of the web therefore run on one side of the first sections, while an intermediate part runs on the opposite side.
In all the embodiments with a web comprising a number of sections, each section can have a length which is the same as or different to that of other sections along the extent of the construction element. As the web, or the central section, on a construction element, or a beam, of the kind indicated above takes up smaller forces when loaded, its dimension can be reduced and/or its longitudinal extent can be reduced to a suitable number of shorter sections. In principle, the central section does not take up any bending forces because these are taken up virtually entirely by the upper and lower sections of the construction element. The central section therefore has to be dimensioned only in order to hold the upper and lower sections in place, and in order to take up vertical load from the upper section, the superstructure of the vehicle (platform and the like) and the load transported by the vehicle.
According to one embodiment, the first and the second profile can have essentially the same cross-sectional profile. For example, two L-profiles can form a U-profile, and two T-profiles can form an I-profile.
According to another embodiment, the first and the second profile can have different cross-sectional profiles. For example, an L-profile and a T-profile can be used.
Irrespective of which profile is used, the first and the second profile can have the same or different dimensions. The web preferably, but not necessarily, has a thickness which is smaller than the thickness of the two first sections it interconnects. Moreover, the distance between a delimiting surface of the web running along a respective first section and the intersection lines of the first and second sections for the first and the second profile respectively can preferably be kept essentially constant.
According to one embodiment, it is possible, for example, for the first profile to be bent so that the distance between the intersection lines of the first and second sections for the first and the second profile respectively converges along at least a part of the extent of the construction element. Along such a tapering part of the construction element, the web, or alternatively its sections, will taper in order to maintain the distance to the respective second profiles.
According to another embodiment, the web is arranged to overlap the first sections. In this connection, the web can be attached to the first sections by means of welding, bolted joints or the like.
According to another embodiment, the outer delimiting edges of the web can be positioned in contact with those edges of the first sections facing these surfaces, the profiles then being welded together.
The invention also relates to a vehicle frame comprising at least two construction elements of the type described above. A conventional frame comprises two beams, which in the present case includes a pair of construction elements consisting of two essentially parallel profiles and at least one third profile interconnecting these profiles.
The third profile preferably consists of a plate which extends along the whole or a limited part of the length of the construction element. Alternatively, the third profile consists of an end plate forming part of a crossbeam which connects the two construction elements. Different combinations of plates and end plates can also be used. In addition to the number of crossbeams and plates, dimensions such as plate thickness and cross section of crossbeams can also be varied freely within the scope of the invention.
The invention will be described in greater detail below by means of a number of different illustrative embodiments with reference to accompanying diagrammatic drawing figures, in which:
The examples below exemplify a number of simplified beams which are intended only to illustrate the inventive idea. As it is not possible to illustrate all possible variations of dimensions such as height, width, length and cross section, of the profiles included in a construction element, only a limited number of examples are shown.
The figures which illustrate the embodiments above are only diagrammatic and show simplified parts of a number of beams according to the invention. The thickness, width and relative positioning of the sections of the web can therefore be selected on the basis of calculations performed for the expected load on the beam. As far as distances between the sections which constitute the web are concerned, it is possible to vary these over and above the examples shown in
The number and positioning of webs, and where appropriate, crossbeams, can be varied freely within the scope of the invention, depending on factors such as size, area of application and load for the vehicle for which the frame is intended.
The number and positioning of crossbeams and webs can be varied freely within the scope of the invention, depending on factors such as size, area of application and load for the vehicle for which the frame is intended.
In this case too, the number and relative positioning of the crossbeams can be varied freely within the scope of the invention, depending on factors such as size, load and area of application for the vehicle of which the frame is to form part.
The invention is not limited to the illustrative embodiments described above and shown in the drawings but can be varied within the scope of the patent claims.
Number | Date | Country | Kind |
---|---|---|---|
0301454-5 | May 2003 | SE | national |
The present application is a continuation patent application of International Application No. PCT/SE2004/000428 filed 23 Mar. 2004 which was published in English pursuant to Article 21(2) of the Patent Cooperation Treaty, and which claims priority to Swedish Application No. 0301454-5 filed 19 May 2003. Said applications are expressly incorporated herein by reference in their entireties.
Number | Date | Country | |
---|---|---|---|
Parent | PCT/SE04/00428 | Feb 2004 | US |
Child | 11164380 | Nov 2005 | US |