MXPA01002306A - Bumper beam assembly and method - Google Patents

Abstract

The present invention relates to improved methods for manufacturing bumper beam assemblies and bumper beam assemblies made by such methods. One method of the invention allows bumper beams of different longitudinal configurations to be made by selecting open cross-sectioned, roll-formed bumper beam members (12) from different sets of beam members and fixing them to bumper beam mounting structures (14). The mounting structures close off the open cross-section of the bumper beam members. Another method of the invention allows bumper beams for varying applications to be made by selecting bumper beam members from inventory and fixing them to a bumper beam mounting structure.

Description

BUMPER ASSEMBLY AND METHOD ASSEMBLY Field of the Invention The present invention relates to head sleeper assemblies and methods for manufacturing same.

Background of the Invention Bumpers of open cross section and closed cross section for conventional motor vehicles are already known in the prior art. It is also known that any type of bumper can be made by forming profiles stamped or stamped. The bumpers of closed cross section of a straight configuration can be formed by the formation of stamped profiles of a continuous sheet of metal so that the longitudinal edges of the same make butt contact with each other and then the seams of these edges are welded, or by stamping two halves of "clam shell" that have a C-shaped cross section and welding the seams of the halves together. Ref. (127419) Each type of bumper is also frequently provided with an arcuate curvature in the longitudinal direction. Frequently this longitudinal curvature, sometimes referred to as the "transverse curvature", is imparted to the metal by passing it through a series of mandrels following a forming operation of the stamped profiles. Conventional open cross-section bumpers are disadvantageous in that such shock absorbers offer less resistance to deformation during impact for a metal gauge and thickness since a bumper of closed cross section. Conventional open cross-section bumpers are often reinforced by increasing the thickness of the metal, which leads to an undesirable increase in the weight and cost of the materials. However, bumpers of open cross section are typically easier to manufacture than bumpers of closed cross section. For example, it is easier to form the rolled profiles and the fold of a bumper of open cross section to provide the transverse curvature of the bumper, even when a steel of relatively high tensile strength is used to build the bumper. That is, it is relatively more difficult to provide a bumper of closed cross section, formed by rollers, straight, with the transverse curvature, because the bending of a beam of closed cross section tends to cause the metallic material to suffer a buckling . Accordingly, there is a need in the art for a bumper beam assembly that provides the impact strength of a closed section beam without the difficulties typically associated with the provision of a desired curvature or transverse curvature to the closed section beam. It is also known in the motor vehicle industry that different vehicles have different strength and size requirements for their associated bumper beams. Conventionally, a different tooling could be required to fabricate the different beams for each particular application. However, the provision of different tools for each particular application is very expensive and takes up manufacturing space that could be used for other purposes. Accordingly, there is a need in the art for a method by which a plurality of different bumper beams can be made using a limited set of tools.

Brief: Description of the Invention It is a purpose of the present invention to satisfy the needs described above. To achieve this object, the present invention provides a modular bumper beam assembly and a method for manufacturing thereof, which solves many of the technical problems described above. The bumper beam assembly according to the present invention is formed by: forming a plurality of elongate bumper beam members by means of rolls from a metal sheet., substantially identical, having each one, a generally open cross section configuration including an open side, the plurality of bumper beam elements include a first set of bumper beam elements having a first longitudinal configuration and a second set of elements of bumper beam having a second longitudinal configuration different from the first longitudinal configuration; stamping from the metal foil a plurality of generally planar, elongate bumper beam mounting structures; and fixing a selected number of the elements of the bumper beam from one of the first and second sets of elements of the bumper beam on a selected mounting structure within the plurality of the mounting structures in such a way that the selected mounting structure Close the open side of each of the selected numbers of the elements of the bumper beam. In accordance with another aspect of the present invention, there is provided a method of forming a plurality of bumper beam assemblies to suit different applications. The method comprises the roll forming of a metal sheet of a plurality of elongated bumper beam members each having a generally identical longitudinal configuration to form an inventory of the elongated bumper beam elements; stamping from the metal foil a plurality of generally planar, elongated bumper beam mounting structures; select a first number of the elements of the bumper beam of the inventory; fixing the first number of the elements of the bumper beam to a selected one of the mounting structures of the bumper beam to form a first bumper beam assembly; selecting a second number of bumper beam elements different from the first number; and fixing the second number of the elements of the bumper beam to a selected one of the mounting structures of the bumper beam to form a second bumper beam assembly different from the first bumper beam assembly. As described hereinafter in detail, this manufacturing method offers numerous advantages. The element of the bumper beam is provided with an open cross section during the roll forming process, and thus it is easier to bend the bumper beam element longitudinally to provide the desired degree of arched curvature, or longitudinal curvature, compared to the fold of a structure with a closed cross section. The closed section is formed of two parts, and therefore a higher strength steel can be used to construct the bumper beam element as compared to the portion of the mounting structure of the closed section. In a preferred embodiment, the elements of the bumper beam can be plugged in or fitted to provide increased bumper strength. According to the other feature of the present invention, the mounting structures of the bumper beam can also be constructed in different sizes to accommodate a selected number of the elements of the bumper beam.

In accordance with other features of the present invention, the mounting structures of the bumper beam can be secured together prior to fixing the bumper beam elements thereto to form larger bumper beam assemblies. Also according to the invention, a plurality of bumper beam elements and identical bumper beam mounting structures can be stored and easily maintained in an inventory to build a wide range of bumper beam assemblies when necessary. Other objects, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims.

Brief Description of the Drawings Figure 1 is an isolated perspective view of a bumper beam assembly with an internal transverse curvature constructed in accordance with the principles of the present invention; Figure 2 is a top plan view of the mounting of the bumper beam of Figure 1; s Figure 3 is an isolated perspective view of an assembly of the bumper beam with an external transverse curvature constructed in accordance with the principles of the present invention; Figure 4 is a top plan view of the mounting of the bumper beam of Figure 3; Figure 5 is a cross-sectional view of the mounting of the bumper beam taken along line 5-5 in Figure 1; Figure 6 is a schematic, side, plan view of a rolling apparatus for construction of the bumper beam elements of the present invention; Figures 7-13 are fragmentary cross-sectional views of an exemplary series of rollers or cylinders grouped in pairs, configured to form by means of the rollers the elements of the bumper beam according to the present invention; Figure 14 is a cross-sectional view of a mounting of the bumper beam according to another embodiment of the present invention; Figure 15 is a cross-sectional view of a mounting of the bumper beam in accordance with still another embodiment of the present invention, wherein a plurality of the elements of the bumper beam have been plugged in to reinforce the assembly; Figure 16 is a cross-sectional view of still another embodiment of the invention, wherein one element of the bumper beam has a cross section in the shape of a double C; and Figure 17 is a further embodiment of a bumper beam assembly employing a bumper beam element similar to that shown in Figure 16, but provided with hollow reinforcing ribs projecting outward to improve impact resistance.; and Figure 18 is an additional embodiment similar to that illustrated in Figure 18, but in which the internal reinforcing hollow ribs have been removed.

Detailed Description of the Preferred Modality of the Invention Figure 1 shows a mounting 10 of the bumper beam for a motor vehicle constructed in accordance with the principles of the present invention. The bumper beam assembly 10 comprises at least one member of the bumper beam, generally designated 12, attached to a mounting structure of the bumper beam, generally designated 14. The bumper beam assembly 10 is an elongated structure and preferably it has a longitudinal configuration having a slight degree of longitudinal curvature, or "transverse curvature", from a first end 16 thereof to a second end 18 thereof. The mounting 10 of the bumper beam can be provided with an internal transverse curvature as shown in Figures 1-2, with an external transverse curvature as shown in assembly 110 of the bumper beam of Figures 3-4, or it can be have a substantially straight longitudinal configuration (not shown), depending on the application. A cross-sectional view of the mounting 10 of the bumper beam of Figure 1 is shown in Figure 5. It should be appreciated that a cross-section through a beam of an opposite longitudinal curvature as in the embodiment of Figure 3, or of a straight longitudinal configuration, they could be substantially identical. The mounts 10 and 110 of the bumper beam shown in Figures 1-5 each include two bumper beam members (respectively) 12 rigidly fixed on the mounting structures 114 of the bumper beam.

With reference to Figure 5, it can be seen that each element 12 of the bumper beam is an integral structure having a portion 20 of the central wall and a portion of the upper and lower wall, 22 and 24, respectively. The upper and lower wall portions 22, 24 respectively terminate in an upper projecting portion 26 and a lower projecting portion 28. The open, C-shaped cross-sectional configuration of each beam element 12 includes an open side designated 30. The elements 12 of the bumper beam and the mounting structure 14 of the bumper beam are preferably made of steel. It is contemplated to use metals having a variety of thicknesses and tensile strengths, but it is preferred to use ultra high strength steel having a KSI value of between about 100 and 220 to form the elements 12 of the bumper beam and use a steel softer having a KSI value of between about 28 and 50 to form the mounting structure 14 of the bumper beam. The softer steel used for the mounting structure of the bumper beam according to the invention facilitates the bending of the mounting structure to adapt to a particular beam curvature if desired.

The elements 12 of the bumper beam can be fixed to the mounting structure 14 of the bumper beam by any suitable means, but the preferred method is welding. A series of puddled welds are shown in the embodiment of Figure 3, designed by the reference number 132. The elements 12 of the bumper beam can be formed by means of rollers from the rollers of the material of the metal sheet of raw material , preferably made of steel, in a conventional rolling machine. A rolling apparatus for forming the elements 12 of the bumper beam of the present invention is shown schematically in Figure 6 and is generally designated by the reference numeral 34. The rolling apparatus 34 generally includes an unwinding station 36 for unwinding the large strips or sheets of the coiled raw material metallic material 38. The rolled metallic material 38 is unwound so that a flat sheet of the material 40 is fed sequentially through a plurality of metal forming devices that include a hardening laminator 42, a roller straightener 44 of storage material, an optional pre-drilling press 46, a conventional laminator 48 and a cutting press 50. The laminator 48 includes several pairs of heavy metal rollers, generally designated as 52. A final set of rollers 52 may comprise a conventional twisting station (not m ostrada) which straightens any twisting in the section formed by means of rollers during shaping. The hardening laminator 44 provides a reduction of the cold metal prior to the rolling process. This increases the strength of the metal and simultaneously reduces the thickness of the metal (e.g., by about five percent) to increase the strength ratio with respect to the weight of the elements 12 of the bumper beam, making it possible for it to be formed within narrower tolerances. The roller straightener 42 of the storage material crushes the metal sheet to remove any imperfections or inconsistencies in the metal. The optional pre-punched press 46 can drill holes in the bumper beam elements 12 that may be required to secure other structures. After the metal sheet is formed by means of the rolls so that it has a generally C-shaped cross section, open, and then provided with the desired degree of longitudinal transverse curvature, a predetermined length of the laminate is cut by the press. cut 50 to form the individual bumpers. In the preferred embodiment described above, the transverse curvature of the bumper beam is provided by the roll forming operation itself. In a preferred embodiment, the bumper beam is laminated in a substantially straight configuration and then subsequently bent at a bending station. Finally, the alternative modality can be advantageous in that it satisfies the particular applications that may arise. On the other hand, the conformation by means of rollers of the bumper beam with the transverse curvature is a more economical and efficient process. Figures 7-12 show in a fragmentary cross-sectional view the pairs of the metal rollers 52 used inside the rolling mill 48 to form the C-shaped cross section of the bumper beam elements 12. Figure 8A shows in a fragmentary sectional view a first pair of rollers 56 and 58 for initially crushing or smoothing the sheet of the input material 40 to remove any imperfections or inconsistencies in the sheet. The first shaping operation is performed with the coupled rollers 60 and 62 as shown in Figure 8. As can be seen from Figure 8, the coupling surface 64 of the roller 60 has a slightly convex cross section and the coupling surface 66 of the complementary roller 62 is slightly concave. These surfaces 64, 66 compress the sheet of material 40 between them, whereby they slightly bend the material as it passes through the laminator. In addition to the shaping of the steel sheet 40, the rotatable coupling of each pair of rollers in the laminator also feeds the sheet 40 to the next pair of rollers. It can be seen from Figures 9-12 that the cooperative pairs of the rollers 68 and 70, 72 and 74, 76 and 78, and 80 and 82 progressively bend the sheet of steel material 40 to form the portions of the upper wall and bottom 22, 24 and form the upper and lower support portions 26, 28 on the respective edges of the upper and lower wall portions 22, 24 (shown in Figure 5). Figure 13 shows a full section view of rollers 76 and 78 for further illustrative purposes. It can be seen that the laminator 48 illustrated in Figures 6 and 8 and the transverse curvature apparatus 88 are configured to provide bumper beam elements 12 having an internal transverse curvature as shown, for example, in Figures 1 and 2. It can be seen that each pair of rollers can be inverted and the transverse curvature apparatus 88 properly reconfigured to provide the bumper beam elements having an outer transverse curvature or a straight transverse curvature. The rolling process is advantageous over the stamping because a complete roll of the metallic material 38 can be processed in a continuous manner without the need to move the elements 12 of the bumper beam to and from a stamping station or between a stamping station. plurality of stamping stations. Furthermore, because the laminate is a gradual process in which a metal sheet is increasingly bent to form the C-shaped cross-section of each element 12 of the bumper beam, the elements of the beam formed by means of the rollers are formed more accurately than if they were formed by stamping. The stamping can also lead to undesirable wrinkling of the metallic bumper elements. The mounting structure 14 of the bumper beam is preferably formed by stamping in essentially planarly spaced sections of predetermined dimensions. As will be explained hereafter, it is contemplated to stamp a plurality of mounting structures 14 of the bumper beam having different heights so that the bumper beam assemblies of a wide range of sizes can be easily constructed. Referring to mounting 10 of the bumper beam illustrated in Figures 1, 2 and 5 by way of example, it can be seen that the mounting of the bumper beam according to the present invention is generally formed by mounting a pre-selected number of the bumper beam elements 12 on a mounting structure 14 of the selected bumper beam. The mounting structure 14 of the bumper beam is substantially straight and flat before it is attached to the bumper beam members 12 and can be bent while they are fixed. Specifically, the mounting structure 14 is preferably fixed to the element 12 of the bumper beam by welding and is progressively bent when it is welded on the element of the bumper beam. It can be seen that the lower tensile strength of the mounting structure 14 of the bumper beam facilitates the bending thereof when it is attached to the element 12 of the bumper beam. The elements 12, 112 of the bumper beam and the mounting structures 14 and 114 are modular in nature so that a small inventory thereof can be maintained and assembled when necessary to produce the bumper beam mounts 10, 110, of different sizes, transverse curvatures and resistances. An inventory of the exemplary modular bumper assembly may be comprised of a plurality of bumper beam elements of the two cross section sizes; and a plurality of mounting structures of the bumper beam of identical length but of different vertical heights. More specifically, each mounting structure of the bumper beam has a length preferably equal to the length of each element of the bumper beam. The mounting structures of the bumper beam may have a range of vertical heights, however, to fit bumper beam members of different sizes, to accommodate a plurality of vertically spaced bumper beam members, and / or to adapt to each plurality of the bumper beam elements vertically spaced with a variety of spacing configurations to suit different applications with the same inventory. Figures 5, 14, 15, and 16 illustrate a plurality of bumper beam assemblies, which can be constructed from a small exemplary inventory. Figure 5, for example, shows in the cross-section an example of a mounting 10 of the bumper beam which can be constructed from a single mounting structure 14 of the bumper beam and two elements 12 of the bumper beam. The cross section in Figure 15 shows the vertical height of the mounting structure 14, but the longitudinal extension thereof is not shown. It should be appreciated that the same elements of the beam 12 can be used for different applications by altering the vertical space between them. In this regard, the mounting structure 14 can be provided with an increased vertical height to accommodate a larger range of vertical spacing variations between the beam elements 12 for different applications. In addition to making variable spacing possible between the elements of the beam, a height of the increased mounting structure also leads to having a different number of the beam elements that are mounted. For example, a mounting plate of increased vertical height compared to the mounting plate 14 in Figure 5 can accommodate three or more open section beams mounted thereon. On the other hand, a reduced vertical height for the mounting plate can be better adapted to a single open section beam.

Figure 14 shows that two mounting groups 10 and 210 of the bumper beam, each of which can be used as the mounting of the bumper beam in and of itself for a particular application, can be combined by being secured together to forming a 310 assembly of the larger bumper beam for still yet another application. The mounts 10 and 210 can be secured together to increase the size range of the bumper beam mounts that can be produced from a given inventory of the identical bumper beam elements 12 and the mounting structures 14 and 214 of the beam of different sizes. In the exemplary embodiment shown in Figure 14, the mounting structure 214 of the bumper beam is adapted only to the single beam 12 which is fixedly welded to the mounting structure 14 of the bumper beam (as illustrated in the Figures). 1, 2 and 5) to form a mounting structure of the bumper beam with a vertical height equal to the sum of the vertical heights of 14 and 214 and sufficient to receive the three elements 12 of the bumper beam. The mounting structures 14 and 214 of the bumper beam are preferably jointly secured by welding the longitudinal edges thereof in a first manufacturing step to produce the mounting structure of the bumper beam of increased vertical height, and this structure of The combined assembly is then used to mount the plurality of the elements 12 of the bumper beam in a second step. Figure 15 shows that a plurality of the elements of the bumper beam (designated 412 and 12) differing only in the cross section, can be plugged in or fitted to form a reinforced or high resistance bumper beam assembly 410. Specifically, the cross section of the beam element 12 is slightly smaller than that of the beam element 412 so that the beam 12 can be plugged in or fitted within the bumper beam 412 as shown to increase the impact resistance and the strength of the assembly 410. An implicit basic principle of the present invention is that a plurality of elements of the bumper beam, which may include the elements with different transverse curvatures and cross-sectional sizes, and a plurality of mounting structures of The generally planar bumper beam differing only in its vertical height may comprise a modular bumper system to provide a plurality of bumper beam assemblies having a wide variety of sizes, configurations, resistances and transverse curvatures to suit a wide range of designs of vehicles and bumper applications. The approach to the construction and design of the bumper made possible by the elements of the bumper beam and the bumper beam mounting structures described above, provides many advantages. The Figures show that each element of the bumper beam has an open cross section but that the element (or the elements if more than one is used) of the bumper beam and the mounting structure of the bumper beam cooperate to provide the assembly of the bumper beam. Bumper beam with a closed cross section. Because each element of the bumper beam has an open cross section during the forming process by means of the rollers, it is easier to provide each element 12, 12d of the bumper beam with the desired degree of internal or external transverse curvature . It is readily understood that when the mounting structure of the bumper beam is secured by welding to each element of the bumper beam in the associated bumper beam assembly, the open side 30 of each element of the bumper beam is closed to increase the strength of the assembly for a thickness and resistance of the metal, of the given type.

It can be understood that in the broader aspects of the. invention, it is contemplated to provide a plurality of essentially identical bumper beam elements 12, each of which is curved or arched generally in the same configuration and the mounting structure of the bumper beam is bent during the bumper assembly process. to conform to the transverse curvature or generally identical arcuate longitudinal configuration of the elements 12 of the bumper beam. It can be seen that the drawings and the preceding examples are proposed to carry out the broad aspects of the invention and are not proposed to be limiting. The dimensions and shapes described herein can be altered within a wide range without departing from the scope of the invention. Figure 16, for example, shows in the cross section, an element 90 of the bumper beam, which was formed by means of rollers to form a plurality of protruding channels or portions 92. This element 90 of the bumper beam has a section transverse essentially with a double C shape. This element 90 may be curved in any direction and may be mounted on a mounting structure 14 to completely close the single open side of the beam element 90 in a manner similar to that described above for a single channel element 12. A plurality of elements of the double channel bumper beam can be plugged in or fitted to form a reinforced assembly. It is also contemplated to reinforce the mounting structure by securing a second mounting structure in a superposed relationship therewith and it is contemplated to provide a plurality of openings as required through the bumper beam elements 12, the mounting structure or both, to facilitate the assembling of the assembly 10 of the bumper beam to the vehicle or the assembly of other structures such as, for example, a cover, to the mounting 10 of the bumper beam when it is installed on a vehicle. It should also be appreciated that each of the embodiments shown in cross section in the Figures may represent assemblies that are curved inward, curved outward, or straight or with degrees of straight configurations. Shown in Figure 17 is a further embodiment of a bumper beam assembly 510 that employs a bumper beam element 590 similar to that shown in Figure 16. In the embodiment of Figure 17, however, each of the Wall portions 522 extending horizontally are provided with hollow reinforcing ribs 527 projecting outward to provide improved beam strength. Figure 18 is an additional embodiment similar to that illustrated in Figure 18, but in which the internal reinforcing hollow ribs have been removed. This construction makes it much easier to provide the bumper beam assembly with the desired transverse curvature compared to the construction of Figure 17. Although the invention has been mentioned and described with reference to a limited number of embodiments, it will be evident that it can be made variations and modifications in it without departing from the spirit and scope of the invention. Therefore, the following claims are proposed to cover all such modifications, variations, and equivalents thereof in accordance with the principles and advantages set forth herein.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Having described the invention as above, property is claimed as contained in the following

Claims (15)

1. A method for forming a plurality of bumper beam mounts, characterized in that it comprises: forming by means of rollers from a metal foil a plurality of elongate bumper beam elements having substantially identical cross-sectional configurations including an open side, the plurality of bumper beam elements include at least a first set of elements of the bumper beam having a first longitudinal configuration and a second set of bumper beam elements having a second longitudinal configuration different from the first longitudinal configuration, providing a plurality of generally flat, elongated bumper beam mounting structures, select a number of elements of the bumper beam from one of the first and second sets of bumper beam elements; selecting a mounting structure of the bumper beam from the plurality of mounting structures of the bumper beam; and fixing the selected number of the elements of the bumper beam on the selected mounting structure in such a way that the selected mounting structure closes an open side of each of the selected number of the elements of the bumper beam.

2. A method according to claim 1, wherein the selected number of the elements of the bumper beam are of the first set of elements of the bumper beam, and wherein the first longitudinal configuration of the elements of the bumper beam selected from the first The assembly comprises a longitudinal curvature, the method is characterized further comprising: folding the selected mounting structure to adapt to the generally identical longitudinal curvature of the selected number of the elements of the bumper beam from the first assembly.

3. A method according to claim 1, characterized in that providing the plurality of the mounting structures of the elongated bumper beam comprises stamping the plurality of mounting structures of the bumper beam from the metallic material.

4. A method according to claim 1, characterized in that the stamping provides the mounting structures of the bumper beam with varying heights.

5. A method according to claim 1, characterized in that the fixing is carried out by welding.

6. A method according to claim 1, characterized in that the selected mounting structure comprises a plurality of stamped metal sheets welded together.

7. A method according to claim 1, characterized in that the selected mounting structure comprises a single sheet of stamped metal sheet.

8, A method according to claim 1, wherein the first longitudinal configuration of the elements of the bumper beam selected from the first set comprises a longitudinal curvature having an internal transverse curvature and wherein the second longitudinal configuration of the elements of the bumper beam selected from the second set comprises a longitudinal curvature having an external transverse curvature, the method is characterized in that it further comprises: folding the selected mounting structure to conform to the generally identical longitudinal curvature of said selected number of the elements of the bumper beam from one of the first and second sets of the elements of the bumper beam.

9. A method for forming a plurality of bumper beam assemblies to suit different applications, characterized in that it comprises: forming by means of rollers from a metal sheet a plurality of elongate bumper beam elements having substantially identical longitudinal configurations and configurations of cross section substantially identical to form an inventory of the elements of the elongated bumper beam; stamping from the metal foil a plurality of mounting structures of the elongate bumper beam; select a first number of the elements of the bumper beam from the inventory; fixing the first number of elements of the bumper beam to a selected one of the mounting structures of the bumper beam to form a first assembly of the bumper beam; select a second number of the elements of the bumper beam different from the first number; fixing the second number of the elements of the bumper beam to another selected one of the mounting structures of the bumper beam to form a second bumper beam assembly different from the first bumper beam assembly.

10. A method according to claim 9, characterized in that the first number of the elements of the bumper beam is one, and wherein the second number of the elements of the bumper beam is two.

11. A method according to claim 9, characterized in that the first number of the elements of the bumper beam comprises two elements of the bumper beam vertically mounted in a manner related to each other on a selected one of the mounting structures of the bumper beam.

12. A method according to claim 9, characterized in that the first number of the elements of the bumper beam comprises two elements of the bumper beam plugged in or nested one inside the other.

13. An assembly of the bumper beam, characterized in that it comprises: a mounting structure of the bumper beam; and a plurality of elongate bumper beam elements, fixed to the mounting structure of the bumper beam, the bumper beam elements have a substantially identical cross section configuration having an open side, the bumper beam mounting structure completely closes an open side of each of the elements of the bumper beam.

14. An assembly of the bumper beam according to claim 13, characterized in that the elements of the bumper beam are mounted vertically in a manner related to each other on the mounting structure of the bumper beam.

15. An assembly of the bumper beam according to claim 13, characterized in that the elements of the bumper beam comprise two elements of the bumper beam plugged in or embedded one inside the other. BUMPER ASSEMBLY AND METHOD ASSEMBLY SUMMARY OF THE INVENTION The present invention relates to improved methods for fabricating bumper beam assemblies and to bumper beam assemblies made by such methods. A method of the invention allows the bumper beams of different longitudinal configurations to be made by selecting the elements (12) of the bumper beam, formed by means of rollers, of open cross section, from different sets of elements of the beam and to fix them to the mounting structures (14) of the bumper beam. The mounting structures completely close the open cross section of the bumper beam elements. Another method of the invention allows bumper beams for variable applications to be made by selecting the elements of the bumper beam from the inventory and fixing them to a mounting structure of the bumper beam.