MXPA06000225A - Bumper system incorporating thermoformed energy absorber - Google Patents

Abstract

A bumper system includes a tubular beam (21) and a thermoformed energy absorber with crush boxes (23) formed into a base flange, such as by vacuum or thermal forming processes. The crush boxes have planar energy-absorbing sidewalls a depth of about 10 mm to 35 mm, wall thickness of about 1 mm to 3 mm, and are formed from polyethylene or other thermoform materials having a memory. The base flange can include thermoformed features engaging recesses in the beam, and is combinable with injection-molded or foam energy absorbers for design flexibility. In one form, the energy absorber includes a thermoformed first sheet forming crush boxes and a second sheet bonded to the first sheet to define apertured air pockets. Related methods of manufacture and impacting are also disclosed.

Description

selected impact (for example, in a corner of the vehicle or in a crash impact, such as in a post impact). Concurrently, all components of a bumper system must be flexible and capable of conforming to an aerodynamic sweeping curvature of a vehicle front. Notably, thermoformed parts have not been used in both bumper systems in modern passenger vehicles, since it is generally accepted in the bumper industry that the energy absorbers must be relatively deep parts (such as approximately 40 mm or more depth). ) and include significant wall thicknesses (eg, 3 mm or greater wall thickness) in order to provide a good grinding stroke and energy absorption during impact. In addition, most injection molded energy absorbers manufactured from solid polymer are relatively complex parts with; Wavy surfaces, varied wall thicknesses and different wall spacings to provide optimum energy absorption in different regions of the energy absorbers. This is directly in opposition to the thermoformed portions, which are basically limited to relatively short depths, relatively constant and relatively thin wall thicknesses (or at least reduced wall thicknesses in stretched areas) and no guide / saw notch surface. - Thus, for years, manufacturers of original passenger vehicle equipment have avoided using thermoformed parts, despite the fact that thermoformed molds in general. they cost less, • they require shorter driving times, they provide faster cycle times, they have lower thermal energy use, they generate less waste and they are more environmentally compatible processes. Technicians experienced in bumper design have apparently not fully realized the unexpected additional benefits that thermoformed parts can offer when combined with other energy absorbing systems and components. Thus, a bumper system having the aforementioned advantages and solving the aforementioned problems is desirable. BRIEF DESCRIPTION OF THE INVENTION In one aspect of the present invention, a bumper system includes a beam and a thermoformed energy absorber having a base flange and thermoformed crush blocks formed perpendicular to the flange of the base, the crush blocks. they have at least one flat side wall and one front wall to form a box configuration.

In another aspect of the present invention, a bumper system includes a beam and a thermoformed energy absorber having a base flange and thermoformed crush blocks generally formed perpendicular to the base flange and longitudinally elongated. In a narrow form, the crush blocks have a transverse cross section with a maximum depth dimension of less than about 35 mm. In another aspect of the present invention, a bumper system includes a beam and a thermoformed energy absorber having a base flange and thermoformed crush blocks generally formed perpendicular to the base flange, the crush blocks have wall thicknesses of about 3.0 mm or less or more preferably less than about 2.0 mm, especially in stretched areas during thermoforming. In another aspect of the present invention, a bumper system includes a bumper beam with a recess element on its face and a thermoformed energy absorber having a base wall with thermoformed elements that engage with the recess member. In another aspect of the present invention, a bumper system includes a tubular metal bumper beam that has a face, a first polymer energy absorber having energy absorbing blocks selected from one or both of the hollow crush blocks and foam blocks and a second thermoformed polymer energy absorber covering a substantial portion of a front part of the first energy absorber polymeric In another aspect of the present invention, a bumper system includes a bumper beam having a face and an energy absorber covering the face. The energy absorber includes a first thermoformed sheet that forms crush blocks with side walls designed to absorb energy and includes a second sheet coupled or fused to the first sheet at selected sites to define air cavities captured in at least some of the crushing blocks. In another aspect of the present invention, a method for providing impact resistance comprises the steps of providing a bumper system including a first sheet with thermoformed side walls that form crush blocks and a second coupled sheet that forms air cavities beneath at least some of the crushing blocks of the first sheet. The method further includes absorbing the impact during a collision which includes in a first step at least partially folding the side walls the crush blocks to absorb some of the impact energy and includes a second step of at least partially folding the cavities of air and compress air in them to absorb additional impact energy. In a narrower form, the method includes ejecting the compressed air through a restricted orifice. In another, narrower form, the method includes the wall recovery stage where the walls forming the crush blocks return to an almost original shape. In another aspect of the present invention, an energy absorber includes a sheet of thermoformable polymer material defining a base wall. The sheet i includes a plurality of thermally formed hollow energy-absorbing crush blocks protruding from the base wall. The crush blocks define a region with at least two different heights that are alternately positioned and intermixed such that after an initial part of an impact chain with an object, the larger crush blocks are initially crushed to provide an first level of energy absorption and after a shock impact rear part, the shorter crush blocks are coupled and crushed to provide a second higher level of energy absorption. In another aspect of the present invention, an energy absorber includes first and second sheets of thermoformable polymer material defining first and second base walls. The first sheet includes a plurality of first crush blocks extending from the first base wall toward the second base wall. The second sheet includes a priority of second crush blocks extending from the second base wall and engaging with the first base wall and further includes a priority of third crush blocks that engage with the first crush blocks. . In another aspect of the present invention, an energy absorber includes a first sheet of thermoformable polymeric material that defines a base wall. A plurality of crush blocks are formed therein. Each of the crush blocks includes a side wall considered to absorb significant energy when impacted and further includes a special bottom flange from the base wall and closing a first end of the crush blocks. The crush blocks include a second open end defined by the marginal material on the base wall. A second sheet is folded to the marginal material and covers the second end to form an air cavity within the individual crush blocks. Through this arrangement, the air is trapped inside the crush blocks, in such a way that it provides an air cushion during the impact. In another aspect of the present invention, an energy absorber for a glass bumper system comprises first and second sheets of thermoformable material, each having a base flange and thermoformed crush blocks generally formed perpendicular to the associated base flanges . At least some of the crush blocks of the second sheet align with and partially fit corresponding blocks of the crush blocks of the first sheet to trap air therein. The crushing blocks and also the trapped air provide absorption of energy in the impact. In still further aspects of the present invention, methods relating to the above methods are disclosed and are believed to be patentable.

These and other elements, objects, and advantages of the present invention will become apparent to a person of ordinary skill upon reading the following description and claims together with reference to the appended Figures. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of a bumper system incorporating a pair of uprights, a tubular beam and a thermoformed energy absorber; Figures 2-5 are perspective, top, front and end views of the thermoformed energy absorber of Figure 1; Figures 6-7 are cross sections taken along line VI-VI and VII-VII of Figure 3; Figure 8 is a partial perspective view of a first modified bumper system similar to Figure 1; Figure 9 is a detailed perspective view of a second modified bumper system, similar to the Figure 1, but showing alternative intermediate energy absorbers between the beam and the thermoformed energy absorber of Figure 1; Figure 10 is a cross-sectional view of figure 9; Figure 11 is a cross-sectional view of a third modified bumper system similar to Figure 10, but including a double layer thermoformed energy absorber incorporating an air cushion element; Figure HA is a cross-sectional view taken along line XIA-XIA of Figure 11; Figure 12 is a cross-sectional view of a fourth modified bumper system similar to Figure 11, but having a modified energy absorber; Figure 12A is a cross-sectional view taken along the line XIIA-XIIA of Figure 12; Figure 13 is a cross-sectional view of a fifth modified energy absorber similar to Figure 1, but having a side wall with a tiered construction of ten tie-downs; Figures 14-16 are cross sections similar to Figure 13, showing a crush sequence to the impact of the energy absorber of Figure 13; Figures 17-20 are cross sections of a modified energy absorbent portion similar to Figure 11; further Figures 18-20 show a crushing sequence on the impact of the energy absorber of Figure 17 and Figure 21 is a graph showing a force versus deviation curve showing a stepped increase in force and energy absorption on the crushing distance, which includes the administration of recovery of the energy absorber after the release of the impacted body; Figures 22 and 22A are cross-sectional views showing a front bumper system incorporating a thermoformed energy absorber of the present invention; Figure 23 is a side view of the thermoformed energy absorber of Figure 22; Figure 24 is a plan view of a polymeric sheet of the energy absorber of Figure 23, the sheet includes a pattern of thermoformed crush blocks; Figure 24A is a cross section taken along line IIIA-IIIA of Figure 24; Figures 25-26 are plant samples and side views of a modified energy absorber and Figure 26A is an enlarged sectional view of a portion of Figure 26; Figure 27 is a second modified energy absorber; Figure 28 is an enlarged fragmentary sectional view of the energy absorber of Figure 23; Figure 29 is a perspective view of another modified energy absorber, including a pattern of thermoformed crush blocks; Figures 30-37 are views of additional modified thermoformed energy absorbers, Figures 30-32 and 36-37 are plan views and Figures 33-35 are side views in lateral cross section; Figure 33A is a cross-sectional view of another modified energy absorber, which includes a laminated two-blade assembly of Figure 33, with opposite interengaged thermoformed crush blocks and two support sheets that provide air trapped in the crush blocks and - Figure 38 is a cross-sectional view of another absorber of modified energy, including first and second thermoformed sheets with crushing blocks thermally formed to vacuum in them and located to fit and trap air between them. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A bumper system 20 (Figure 1) includes a tubular beam 21 formed by B-shaped lamination and scanning with uprights 21 'adapted for connection to the front rails of a vehicle frame and an energy absorber. thermoformed 22. The energy absorber 22 has a base flange 24 and a plurality of thermoformed crush blocks 23 thermally preformed from the material of the base flange 24, such as by vacuum forming processes. Each of the crush blocks 23 has flat energy absorbing side walls 25-28 (Figure 4) and a front wall 29 to form a box shape with the flange side of the base of the box form that is open . The crush blocks 23 have a thickness (ie, height) of any of about 10 mm to 60 mm and more preferably, a height of about 20 mm to 30 mm, depending on a space in front of the beam 21 as it sweeps around a vehicle front. The vacuum formed energy absorber has a selected shape for supporting the fascia on the beam 21. It is contemplated that differently formed energy absorbers 23 may be coupled with the same beam 21 to provide fascia support in different vehicle models. Given the low cost of the ornamental for the thermoformed parts and the high cost for the ornamental of the beams 21 and other energy absorbers molded by injection, this is a tremendous advantage. The walls 25-29 of the crush blocks 23 may have wall thicknesses of any thickness, such as about 1 mm to 3 mm, but preferably have a wall thickness of about 2.0 mm or less, or more preferably a wall thickness of about 1.5 mm or less and potentially have a wall thickness of about 1.0 mm or less. In particular, the thickness of the walls that are stretched during the process aided by thermoforming vacuum can be significantly reduced, especially in acute radios. Notably, the depth and wall thicknesses are somewhat enlarged in views of Figures 1-7 to better illustrate the present invention. The thermoformed energy absorber 22 can be formed from any thermoformable material, but is preferably formed from polyethylene polymers, such as high density polyethylene ("HDPE"), which has memory and will recover and flex back toward an original thermoformed shape after being crushed. during a vehicle impact. It is also conceived that a shape similar to the illustrated energy absorber 22 can be injection molded, although the cost of the ornamental for such can be significantly more expensive than for a thermoformed part. The base flange 24 has thermoformed elements 32 '(FIG. 2) that engage with one of the two longitudinal channels or recesses 35 in one face of the beam 21, thus helping to retain the energy absorber 22 on the beam 21. Al changing the thickness of the material, type of material, corner radius and other factors, the energy absorber 22 can be rotated to provide optimum energy absorption for the system. The beam 21 of the bumper can be of a variety of different shapes and profiles. The illustrated beam 21 is of the "B" form but it is conceived that it could be "D" shaped, "C" shaped or other shapes. The illustrated beam is formed by rolling and tubular, which is a preferred mode based on its strength and relatively lower cost. The energy absorber 22 (Figures 3-4) includes horizontal upper and lower rows of crush blocks 23. The upper and lower crush blocks 23 are vertically approximately equal in height and are approximately equal to the respective upper and lower tubular sections. the beam "B" 21, which are placed opposite D. Thus, the upper and lower walls 27-28, extend horizontally, are generally aligned or slightly on board with the upper and lower horizontal walls of the respective tubular section of beam "B" 21 behind them. In addition, walls 27-28 (and potentially also walls 25- 26) are undulated by increased resistance and stability. The crush blocks 23 can be of variable length, size and height to optimize crush resistance in selected regions of the bumper system. For example, the illustrated crush blocks 23 near the ends of the beam 21 of Figures 3-4 are longer than the intermediate positioned crush blocks 23. Also, the crush blocks illustrated 23 may be spaced apart in equal amounts. or unequal. Each of the crush blocks 23 is spaced apart by an interconnecting strip 32. The illustrated strips 32 include two U-shaped recessed or arched elements 32 '(FIG. 4) which extend rearwardly of the base flange 22 and which are adapted to casually fit respective recessed channels 35 (Figure 1) in the front wall 29 of the beam 21 in a manner that helps to accurately and stably locate the energy absorber 22 on the beam 21. Specifically, the elements 32 'help to prevent the energy absorber 22 from slipping undesirably upwards or downwards during an impact. It is envisaged that the bands 32 may include other elements for coupling and locating on the beam 21, such as bulbous hooks or detents. The channels 35 extend longitudinally through the front face 29 of the beam 21 and are generally placed opposite the respective upper and lower tubular sections on the beam 21. It is preferable that the walls 25-29 remain relatively flat and that the crush blocks 23 have parallel walls or are of pyramid or trapezoidal shape, but it will be noted that there will be some distortion of the walls due to the natural thermoforming properties. Also, the walls must have some angle of drag, such as a degree to two degrees, to facilitate the thermoforming process. It will further be noted that the walls 25-29 are joined together and to the base flange 24 by small radii, which is a necessary practice in the thermoforming industry to prevent tearing and facilitate stretching of the material during the thermoforming process. Typical radii are at least approximately equal to the thickness of the material. However, it is widely accepted in the industry to provide larger radii as necessary to prevent the walls from becoming too thin in areas of high stretch. 'Modified bumper systems- "and additional energy absorbers are shown in.

Figures 8-20. In these systems and additional components, many of the identical or similar components, parts and elements are marked using the same identification number but with the addition of a letter "A", nB "," C "or etc. This is done to reduce unnecessary and redundant discussion However, it will be noted that sometimes two similar thermoformed sheets are glued together, so that different numbers are used to avoid confusing the two sheets (For example, see Figures 11 and 38). bumper system 20A (Figure 8) includes a "B" beam 21A and a thermoformed energy absorber 22A on its face In the energy absorber 22A, the crush blocks 23A have an "I" shape or sideways shape "H" in front view This gives the individual crush blocks 23A additional resistance and stability It is contemplated that the crush blocks 23A may be of other shapes as well, such as "T" shape or "X" or "C" or "0" or, "N". Notably, the face wall or front wall 29A of the energy absorber 22A is generally planar, but can be contoured vertically and horizontally to coincide with a profile of the fascia, such as being tapered near the ends of the beam 21A. Also, the bands 32A provide some longitudinal flexibility to the energy absorber 22A. Through this arrangement, the parsed of the 29A face better matches the aerodynamic curvilinear shape commonly found in modern passenger vehicles. The bumper system 20B (Fig. 9) includes a beam in the form of,? B "2IB (or a beam in the shape of" D "21B '), a thermoformed energy absorber 22B and a second intermediate energy absorber in the form of one of the energy absorbers 37B, 37C or 37D The energy absorbers 37B, 37C or 37D are interchangeable and illustrate an advantage of the present thermoformed energy absorber 22B. Each energy absorber 37B, C, D includes a shoulder formed for fitting to a recess in the form of channel 35B (or 35B ') on beam 21B (or 21B') Energy absorber 37B includes a one-piece injection molded component 38B made of an injection-moldable material such as XEN0Y (manufactured by GE Company) forming block-like energy absorbing blocks 39B and interconnecting U-shaped bands 40B and further includes a priority of energy absorbing foam blocks 4IB placed between blocks 39B. to box 39B are hollow and include open back sides, such that they can be manufactured by a single simple injection molding process. The foam blocks 41B snap between the box-like blocks 39B. The thermoformed energy absorber 22B forms a cover that closes a face of the intermediate energy absorber 37B. The energy absorber 37C is a one-piece injection molded component and includes backward-open box-like blocks 39C and further includes open front areas 42C interconnecting the 3-C box-like blocks. The intermediate energy absorber 37D is made entirely of foam and is adapted to replace the energy absorber 7C. Alternatively, the foam energy absorber can be manufactured to be spliced with one face of the injection molded energy absorber 37C. As can be seen, a variety of different intermediate and hybrid energy absorbing components can be placed between or with the beam 2IB and the thermoformed energy absorber 22B. Figure 10 illustrates a bumper system 20E incorporating a "D" beam 21E, an injection molded energy absorber 37E and a thermoformed energy absorber 22E, with a TPO front fascia 43E placed thereon. Advantageously, different thermoformed energy absorbers (22E) with crush boxes (23E) can be used with the beam 21E and the primary energy absorber 37E, allowing the same beam 21E and the energy absorber 37E to be used in different models of vehicles having fascias formed differently (43E). Specifically, it is potentially a tremendous advantage to use a common injection molded part and / or link in different platforms or vehicle models. The 22E thermoformed energy absorber is used to fill spaces of variable size along the different fascias to treat different style surfaces. The thermoformed energy absorber is particularly advantageous for satisfying this need, since the ornamental is relatively inexpensive and can be manufactured relatively fast and in addition the thermoformed energy absorber itself can have a much lower cost and weight, depending on the design and other criteria. It is contemplated that the thermoformed energy absorber 22E may be held in place on one face of the intermediate energy absorber 37E by the front fascia 43E. alternatively, it is contemplated that various connection mechanisms may be used to attach the thermoformed energy absorber 23E to the injection molded intermediate energy absorber 37E, such as by placing hooks 37E 'on the intermediate energy absorber 37E which engages openings or surface elements on the thermoformed energy absorber 22E and / or other male and female connections such as seals and frictional coupling on splicing surfaces, thermally staked connection arrangements, folding arrangements and other connection systems. It will be noted that the bumper system 20E of Figure 10 is highly environmentally compatible and utilizes recyclable components and in particular does not include either a thermoformable material or a foam material that is difficult to recycle. In addition, the thermoformed energy absorber can be easily separated from other materials, making recycling even easier.

The bumper system 20F (Figures 11-11A) includes a D-shaped beam 21F and a 50F energy absorber on a front surface. The energy absorber 50F (Figures 11-12) includes a thermoformed sheet 22F and further includes a second sheet 51F coupled to the thermoformed sheet 22F to form cavities with trapped air below the crush boxes 23F. The two sheets 22F and 51F are attracted together as long as they are hot and contained in local points to melt and / or fold them together to form an air tight joint. In particular, the blade 51F has a base flange 52F and several bulbous pillow-shaped regions 52F that extend partially to the crush boxes 23F of the sheet 22F: One or more small ventilation holes 54F are formed in each of the pillow-shaped regions 52F. Sheet 51F may have a thickness similar to sheet 22F or may be substantially thinner, such as 0.5mm or even 0.1mm. The preferred sheet thickness depends on the functional requirements and material selection for sheet 51F. It will be noted that the energy absorber 22F may still have the bands between the crush boxes 23F (see bands 32 in Figure 1) where the bands engage the recesses / channels (35) in the face of the beam 21F, but the bands are not shown in Figure 11 to better show the present invention of the sheets 22F and 51F.

It is contemplated that the blade 51F will maintain its shape and function as follows when the bumper system 20F is impacted. During the initial phase of the impact, the crush boxes 23F on the sheet 22F crushed by the impact, begin to crush, causing the air to be pressurized within the cavities 52F. As the pressure increases, air begins to escape through the ventilation holes 54F. As the front wall 29F of the sheet 22F reaches a front surface of the pillow-shaped regions 53F, the sides of the pillow-shaped regions 53F, the sides of the pillow-shaped regions 53F have expanded and coupled and supporting the walls of the crush boxes on the sheet 22F. After further crushing, the sheets 22F and 51F are coupled together. Notably, during this last crushing phase, the walls of the sheets 22F and 51F support each other and increase the overall strength of the crush boxes 23F. Optimally, the sheets 22F and 51F are made of material having memory, in such a way that they recover their shape after impact. The energy absorber 22F '(Figures 12-12A) is similar to Figure 11, but the pillow-shaped regions 53F' are box-shaped or trapezoidal in shape to fit and match the lower half of the side walls ( 25F'-28F ') of the crusher boxes 23F' on the sheet 22F '. Thus, the walls of the sheet 51F 'engage and support and reinforce the walls 25F'-28F' of the energy absorber 23F 'during the final phase of a crush impact. A variety of different shapes and arrangements are contemplated for the concept of trapping air within and between thermoformed sheets. Not only can the material and the thickness of the two sheets be varied, but also the shapes of the crush boxes, the shapes of the pillow-shaped areas and the shapes, size and number of ventilation holes. It is also contemplated that different fillings can be placed in the cavities, unlike air. However, the light weight and low air cost is difficult to match while still maintaining a low weight competitive system. Figure 13 illustrates a 20G bumper system with a 21G beam and a thermoforming energy absorber 22G wherein the side walls 26G-28G include flat sections 58G, 59G and 60G connected by brackets 61G and 62G. A front wall 29G closes a front part of each crush block 23G. The 61G-62G supports cause the 58G-60G flat sections to be coupled together in layers and in a predictable energy absorbent manner, as illustrated in Figures 13-16. As illustrated, sections 58G and 59G are first plugged together (Figure 14) and then sections 59G and 60G are plugged together. After that, all the thermoformed energy absorber 22G retreats to an ultra-thin state where it absorbs very little thickness. The thickness of the folded system is considered an important property of the energy absorbers 22-22G. Since the sheet from which the thermoformed energy absorbers are manufactured is relatively thin, its folded state is virtually only about twice or perhaps three times the original sheet thickness. Thus, it takes "full advantage" of the limited space it occupies, both by filling the space for maximum energy absorption and providing a maximum stroke to absorb that energy in the impact. Figure 17 illustrates another bumper system 2OH having a beam 21H and a thermoformed energy absorber 50H similar to energy absorber 22G, but incorporating a leaf catching air 51H similar to sheet 51F (Figures 11-12), specifically when it is impacted The sheet 22H is folded at the level of the sheet 51H, with trapped air being expelled through the ventilation hole 54H. Then, the sheets 22H and 51H are folded together (Figures 18-20), providing an increased rate of energy absorption. Figure 21 shows the force deviation curve of the three-stage folding of the energy absorber 22G. A graph of similar staggered energy absorption occurred with the 50H energy absorber, although the stages they will be at different heights and will be affected by the energy dissipated by the trapped air that escapes. The illustrated arrangement includes a front end 119 (Figure 22) of a vehicle containing a bumper system 120 comprising a reinforcing beam 121, a primary energy absorber 122 and a subassembly 123 of thermoformed secondary energy absorber, all covered with a fascia 124. The sub-assembly 123 of the Thermoformed energy absorber provides low cost complementary energy absorption to the bumper system and is very useful when finely adjusting the bumper system for particular model vehicles. This potentially allows the same bumper system to be used on different vehicles, but with the addition of the sub-assembly 123 thermoformed absorber for the "extra" energy absorption capacity defined for that particular vehicle. Also, sub-assembly 123 of thermoformed absorber can be manufactured relatively thin, such as from 30mm to 20mm or less or it can be manufactured tapered from end to end, such that sub-assembly 123 of thermoformed absorber can be used in areas " empty "small previously wasted and not used to absorb energy. Also, subset 123 of thermoformed absorber can be used as a fascia surface component to support fascias having different appearance surfaces and contours, where it still allows the use of the same bumper beam and primary energy absorber thereunder. Notably, the subset of thermoformed absorber 123 can potentially be used directly on reinforced beams 121 (Figure 22A) depending on whether energy absorption cavity and fascia support is desired. Also, the systems of Figures 22, 22A can be used in front or rear ends of vehicles and in other applications that require energy absorption on impact. As indicated above, it is contemplated that a variety of different forms, arrangements and configurations can be constructed using the present concepts. Thus, although each individual possible combination is not explicitly described herein, it is proposed that all such combinations and variations be covered by the present disclosure, as may reasonably be understood from this description. With this in mind, the following materials are organized to describe several different thermoformed individual sheets and then to describe two sheets inter-coupled with energy-absorbing crush blocks that intertwine and interact on impact and to describe two sheets folded together to define blocks of crushing that trap air. Through the different arrangements, a wide variety of different force versus deviation curves can be obtained, in which stepped energy absorption curves and energy absorption curves are included where the substantial energy is absorbed in the impact. The energy absorber subassembly 123 (Figure 23) includes two sheets 125 and 125A of thermoformed polymeric material, each sheet defining a base wall 126 and 126A (see also Figures 24-25) respectively, with a plurality of crush blocks 127 and / or 127A thermoformed therein and further includes a pair of carrier sheets 128 attached to the back of the sheets 125 and 125A. The 125 and 125A will be initially described, then their combination with the backing sheets or backing sheets 128. After this, various leaf varieties 125 and 125A will be described. Leaf varieties 125 will be described using the letters "A", "B", etc., for similar and / or identical elements and aspects. Each crush block 127 of the blade 125 (Figures 24 and 24A) includes a thermoformed sidewall 130 from marginal material 131 in the base wall 126. The thermoformed material forms a hole 132 at a center of the crush block 127 and a floor flange 133 spaced from side wall 130 and closing a remote end of crush block 127. Remarkably, it is known in the thermoforming process art to include a radius at the corner formed by side wall 130 and floor flange 133 (and also include a radius in the corner formed by the side wall 130 and the base wall 126) in order to prevent overstretching and weakening and / or tearing of the polymeric sheet material during the tempering process. It is contemplated that the side wall 130 may be of a variety of different shapes, including cylindrical, frustoconical, rectangular, oblong, pyramid, "X" shaped, "I" shaped, or any other structural form. that can be desired. The floor flanges 133 on the sheet of the energy absorber illustrated 125 are all in the form of a cup and are of the same height and size. The illustrated arrangement of the crush blocks 127 on the sheet 125 forms a rectangular arrangement and closely resembles a cake baking tray. It is contemplated that other patterns and shapes of the crush cluck (such as flat-sided pyramids) are also possible. A hole or aperture 135 may be included on the upper entrance flank of the crush block 127, if desired, for air flow or to adjust to provide optimum crush resistance. Also, the thickness and sheet material can be changed to adjust the energy absorber to have the desired force-deflection curve and desired impact energy association. The blade 125A of the energy absorber (Figures 25-26) includes a similar array of crush blocks 127A that identically match the pattern and size of the crush blocks 127 on the blade 125 and further includes within the array a second pattern of higher crush blocks 127A '. The illustrated crush blocks 127A 'are about twice the height of the crush blocks 127A and are formed and positioned to fit between the crush blocks 127. By this arrangement, an upper part of the crush blocks 127A' is they engage with the base wall 126 of the sheet 125. Also, the shorter crush blocks 127A are coupled with the ends of the crush blocks 127 (see Figure 28). As illustrated in Figure 28, the two energy absorbers 123 and 123A can be arranged with their crush blocks 127 that interengage, such that their side walls 130 and 13OA are coupled and support each other. (See broken lines in Figure 24, illustrating crush blocks on a docking sheet that interengage with and support crush blocks 127 on the illustrated sheet). Remarkably, any one or more of the crush blocks 127, 127A, 127A ', can be made shorter or longer, which would result in a force versus step shift curve. Thus, a different level of energy absorption is provided depending on the impact stroke length experienced. This is a very useful property and allows the bumper systems to be adjusted to match particular functional requirements. A sheet of reinforcement or roof support (Figure 27) is attached (optionally) to a rear surface of the marginal material 131 around each squeeze block 127 on the sheet 125, covering the open layer of the squeeze blocks 127. This traps air within the cavities 132 of the slab blocks. flattening 127, forming an air cushion on impact. A hole 135 is formed in the backing sheet 128 (or in the side wall) to allow the air to escape in a shaped manner on impact, such that the crush blocks 127 do not explode unless there is a severe impact. . The hole 135 can be made to any desired size and multiple holes can be used if desired. It is also contemplated that the channels 132 '(Figure 27) may be formed on the backing sheet 128 to communicate the air escaping from a crush block 127 to an adjacent crush block 127. This distributes the stress as well as provides a "fluid" air cushion. Notably, the channels can be bidirected to control the speed of the air flow, as well as the routing or prosecution of the air flow. The sheets 125, 125A and 128 can be of any material or thickness. In the illustrated arrangement of Figure 23, it is contemplated that the sheets 125 and 125A will have sufficient strength and wall thickness to provide good energy absorption in the crushing of their side walls 130 and 13OA, such as about 1 mm to 4 mm. thickness or more preferably around 2 mm to 2.5 mm in thickness and it will be an impact absorbing material that can be thermoformed or vacuum formed easily. However, the sheet 125 and 125A could be injection molded or otherwise formed to have thicker or thinner walls if desired. It is contemplated that the illustrated sheets 125 and 125A will have a total thickness dimension of about 20 mm to 30 mm, but their total thicknesses can of course vary as desired. It is further contemplated that the backsheet 128 and 128A will have a much thinner wall, such as less than 1mm and more preferably less than about 0.5mm and will be of a semi-flexible and bendable material. Since the backing sheet 128 is placed against the face of a bumper beam 121 or against a face of a primary energy absorber 122 (or against another backing sheet 128 when multiple subsets 123 are laid together), the backing sheet 128 does not need to be 2 mm or thicker ... although it could be, if desired. The illustrated side wall 130 extends approximately 90 degrees to the base wall 126, but in reality a small pull angle (such as about one degree) is included to facilitate the thermoforming process. The side walls 130 can include larger angles, but it is preferable that the side wall 130 is not angular more than 45 degrees. It is also contemplated that one (or more) of the blades 125, 125A, 128 may include laterally extending flanges and friction hooks or bearings extending rearwardly on the upper surface of the beam 121 (Figure 22A) for frictional engagement and retaining the subset 123 or on a beam 121 or primary energy absorber 122 (Figure 22) or fascia 124, if desired. Also, the height of the crush blocks 127 can be varied to obtain a tapered or aerodynamic shape to better match a particular contour, such as a swept bumper face. The sheets 125B-125H can be exchanged with the sheets 125 or 125A. Symmetric or similar elements are identified with the same numbers to simplify the discussion.

Sheet 125B (Figure 29) has donut-shaped crush blocks 127B with side walls 130B, but has a modified floor flange 133B, where a central section 140B of floor flange 133B is inversely thermoformed to position its center section 140B approximately coplanar with the base wall 126B. An internal side wall 14IB is formed but which is generally parallel to the outer side wall 13OB. It is also contemplated that the central section 14OB could only be partially deformed, in such a way that it would not be coplanar with the base wall 126B ... in which case the sheet 125B would provide a stepped energy absorption (force versus deviation curve). -. - The sheet 125C (Figure 30) illustrates a circumstance where the crush blocks 127C are formed from a base wall 126C and have "the inner and outer side walls 141C and 13 OC positioned relatively together. 125D (Figure 31) is similar to the blade 125C, but the inner and outer side walls 14ID and 13OD of the crush blocks 127D are positioned relatively far apart The blade 125E (Figure 32) illustrates a circumstance where the center section 140E is only partially recessed and not recessed to be coplanar with the base wall 126 E. The sheet 125F (Figure 33) is similar to the sheet 125E, but on the sheet 125F, the area 142F between the internal and external side walls 141F and 13OF is spaced halfway from the base wall 126F and a central region or end 14OF of the center section is thermoformed to be spaced apart from the base wall 126F that the area 142F. omentum 143F is formed by the central region 14OF and internal side wall 141F. The subset 123F '(Figure 33A) includes a pair of sheets 125F, with the outer side walls 13OF on a sheet engaging and supporting the inner side walls 141F on the sheet sheet 125F. Sheet 125G (Figure 34) is similar to sheet 125F, but on sheet 125G, its tip 143G has a much larger 144G end. The sheet 125H (Figure 36) illustrates a condition wherein two different crush blocks 12H and 127H 'are formed in the base wall 126H. The first crush block 127H is cylindrically formed and extends to a first height. The second crush block 127H 'has a shorter cylindrical shape and includes a prominent tip 143H extending at a shorter height than the crush block 127H. Thus, the sheet 125H will tend to produce a three-tier or three-level crush hopper (force versus deviation curve), each level increasing - in strength with respect to the previous level. In sheet 125H, crush blocks 127H and 127H 'have external side walls 13OH that are spaced together. However, it is contemplated that a sheet 1251 (Figure 37) can be constructed where sidewalls 1301 are supported together at site 1301 ', as it is formed on a single sheet without the need for a second sheet. Figure 38 shows still a further energy absorber 200 in which first and second sheets 201 and 202 are each thermoformed to have the shape somewhat similar to a cake tray. Specifically, the sheet 201 has a base wall 203 with tower-like pyramid-like projections 204 that form crushing blocks of a height 205 and a sheet 202 has a base wall 203, with tower-shaped projections 207 that form crushing blocks of a lower height 208. Several (or all) of the projections 207 fit or snap into the projections 204 with a LEGO ™ -like coupling to form air-cushion cavities 210. A hole or aperture 211 it can be formed in one of leaves 201 or 202 to allow air to escape on impact. Alternatively, air can escape at the corners of the projections. By this arrangement, the energy absorber provides stepped energy absorption and is capable of recovering after the release of the impacting object. Notably, the side walls of the projections 204 and 207 are integrated as well as a pull angle to allow thermoforming, but also in such a way that they are additionally engaged during impact to more tightly seal the air trapped therein. In addition, each of the walls is supported against each other to provide additional support to prevent premature crushing on impact. This inter-wall support extends only part of the height 205 (this is, due to the short height 208), in such a way that it results in a staggered energy absorption at the impact. To summarize, a thermoformed energy absorber can be manufactured from a single sheet, with crush blocks that are formed by vacuum forming or other thermoforming techniques. It is contemplated that the crush blocks may be of any shape, including a "cake tray" pattern or other more complicated cup or box shapes. It is contemplated that crush blocks will be manufactured from material that will recover after impact, although this is not required. The energy absorbers can be manufactured from other processing methods than thermoforming, such as injection molding. The energy absorber can be manufactured to provide a one-stage energy absorption curve (force versus deviation curve) or it can provide step energy absorption. The sheet can be made to be bent to coincide with a sweeping curve through one face of the reinforcing (metal) beam (or primary energy absorber) and can be considered with flanges, such as hook flanges 160 (Figure 22A) which are coupled with holes or recesses 162 in the beam 121 or in the primary energy absorber 122 to be attached post-insertion in place. The blade of the energy absorber can be modified by anchoring a reinforcing sheet to trap air, such that the blade provides an air cushion on impact. Alternatively, the reinforcing sheet can be removed by attaching the sheet directly to a beam (or a fascia) with the crush blocks that are held in a sealed array. Holes and / or channels may be provided to control the air flow out of the crush blocks during impact and to communicate the exhaust air to other crush blocks. Two opposite sheets with itera-coupled and inter-supported crush blocks can be used as a laminated subset. The crushing blocks may be identical or different but formed casually. Additional layers of leaves can be added, in addition to only two leaves. The sheets will preferably be manufactured from a material that recovers after impact and is still easily formed.

In the above description, it will be understood by persons skilled in the art that modifications to the invention can be made without deviating from the concepts disclosed herein. Such modifications will be considered "to be included in the following claims, unless these claims, by their language expressly reaffirm otherwise.It is noted, that in relation to this date, the best method known by the applicant to carry In practice, said invention is the conventional one for the manufacture of the objects to which it refers.

Claims (34)

1. CLAIMS Having described the invention as above, the content of the following claims is claimed as property: 1 . A bumper system for a vehicle, characterized in that it comprises: a reinforcing beam adapted for attachment to the frame of a vehicle and an electromagnetic energy absorber supported on one side of the reinforcement beam, the abs spherical energy orb starting from a sol to a leaf of material by a thermoforming process to have a base flange and a plurality of thermoformed longitudinally arranged crush blocks extending generally perpendicular from the base flange in a longitudinal direction parallel to an expected impact direction; the crushing blocks each have opposite side walls and orthogonally related end walls and a front wall supported by the side wall with the crushing blocks each spaced apart from each other along the base flange; each of the crushing blocks defines a separate front-to-back hole and the side walls, end walls and front walls are continuous; the energy absorber defines a forward facing surface and a back facing surface, each is open and unobstructed in a linear direction parallel to the longitudinal direction and has no guide notch surfaces, whereby the energy absorber it can be thermoformed from the material sheet by passing a portion of the molding ornamental in a direction of formation parallel to the longitudinal direction through its base linearly to the front-to-back holes defined by the crushing blocks; the opposite side walls are stretched by the thermoforming process and have a thickness dimension smaller than the thickness of the front walls and the base flange due to the thermoforming process. The bumper system according to claim 1, characterized in that the reinforcing beam has a first front surface defining a first relatively flat shape and wherein the front walls define a second front surface having a second relatively flat shape different from the first form, the second form is adapted to engage and support a fascia. The bumper system according to claim 1, characterized in that the crush blocks have at least one concavity defined laterally in one of the side walls, such that the crushing blocks, in frontal view, define one of an "H" shape, a "T" shape, an "X" shape and a "C" shape. The bumper system according to claim 3, characterized in that at least one of the side walls has a corrugated shape with corrugations extending parallel to the longitudinal direction. The bumper system according to claim 3, characterized in that the crush blocks are spaced apart longitudinally and each extends vertically at least half of a total vertical dimension of the energy absorber. The bumper system according to claim 2, characterized in that starting from the center of the energy absorber, the internal parts of the internal crush blocks have a different height dimension in a longitudinal direction than the external parts of the blocks of flattening. The bumper system according to claim 1, characterized in that the opposite side walls define planes that extend generally parallel to the longitudinal direction. The bumper system according to claim 1, characterized in that at least one wall side includes a front portion that defines a close-up, a second portion defining a second plane parallel to the first plane and a displaced connection portion which, when the bumper system is impacted, causes the first and second portions to overlap or overlap each other. 9. The bumper system according to claim 1, characterized in that it includes a second sheet of material stuck to the individual sheet of material and forming air-cushioning cavities, filled with air inside the crushing blocks. The bumper system according to claim 9, characterized in that the second sheet of material includes ventilation holes for controlling the flow of air exiting from the air-cushion cavities. 11. The bumper system according to claim 1, characterized in that the face of the reinforcing beam includes one of a depression element and a protrusion element and the base flange includes the other of the depression element and the protrusion element and wherein one element engages the other element to retain the energy absorber on the face of the reinforcement beam after an impact against the bumper system. The bumper system according to claim 11, characterized in that the depression element is a channel and the protrusion element is a shoulder. 13. The bumper system according to claim 1, characterized in that it includes a second thermoformed energy absorber with second crush blocks formed therein that engage against the first mentioned crush blocks. The bumper system according to claim 1, characterized in that the crush blocks have a cross section with a maximum height dimension of about 35 mm. 15. The bumper system according to claim 14, characterized in that at least some crushing blocks have a height dimension of a maximum of about 25 mm. 16. The bumper system according to claim 1, characterized in that the side walls have thicknesses of less than about 2.0 mm. 17. The bumper system according to claim 1, characterized in that the absorber of Thermoformed energy includes a material that has memory and that will recover to near its original shape after being crushed. 18. The bumper system according to claim 1, characterized in that the base flange includes flexible sections located between the crush blocks, such that the energy absorber is bendable and is adapted to flexibly deform and to engage with a face of a curvilinear sweep beam. 19. The bumper system according to claim 1, characterized in that it includes a second energy absorber placed on and engaging with the face of the beam and having a front surface that engages and supports the thermoformed energy absorber. 20. A bumper system characterized in that it comprises: a beam and a thermoformed energy absorber having a base flange and thermoformed crush blocks formed therein, the crush blocks are spatially separated and each has side walls, walls of the end and a front wall to form a box shape, at least one of the side walls includes a front portion defining a first plane, a second portion defining a second plane parallel to the first plane and a displaced connection portion which, when the bumper system is impacted, it causes the first and second portions to plug over each other in a predictable manner. 21. The bumper system according to claim 20, characterized in that it includes a second blade bonded to the thermoformed energy absorber, the second blade has portions forming air-filled air-cushion cavities below the crush blocks. 22. A bumper system characterized in that it comprises: a bumper beam having a face and at least one elongated recess formed in the face and a thermoformed energy absorber having a base flange and crush blocks formed in the absorber of energy in a direction perpendicular to the base flange and further having at least one thermoformed shoulder extending from the base flange to a coupling with the recess to retain the energy absorber on the face during a vehicle collision. 23. The bumper system according to claim 22, characterized in that the recess comprises a longitudinally extending channel formed in one face of the beam. 24. A bumper system characterized in that it comprises: a tubular metal bumper beam having a face; a first polymer energy absorber having energy absorber blocks selected from one or both hollow crush blocks and foam blocks and a second thermoformed polymer energy absorber covering a substantial portion of a front part of the first polymer energy absorber, The second polymer energy absorber includes a base flange that couples the first polymer energy absorber and includes at least one crush block formed therein. 25. The bumper system according to claim 24, characterized in that the first and second polymeric energy absorbers include coupling surfaces that engage frictionally and restably to retain the energy absorbers together. 26. A vehicle bumper system characterized in that it comprises: a reinforcing beam having a face and adapted for attachment to a vehicle frame; an energy absorber that is connected to the face that includes a thermoformed component and a fascia that covers the beam and the energy absorber; the thermoformed component has a base sheet adjacent to the face and a plurality of crush blocks extending forward from the base sheet in engagement with the fascia; each of the collapsing blocks has opposite side walls and a front wall defining orthogonally related planes and also having upper and lower walls which are corrugated in a longitudinal direction with alternating convex and concave regions; the crushing blocks are open on at least one side to facilitate the thermoforming of the thermoformed component, the crushing blocks define selected shapes of the group of shapes in which at least one of the side walls defines a concavity. 27. The bumper system according to claim 26, characterized in that the at least one side wall has a shape consisting of one of the following forms: I, H, CT and X. 28. The vehicle bumper system in accordance with with claim 27, characterized in that the side walls of the crush blocks include at least two different forms of the forms I, H, C, T and X. 29. The vehicle bumper system according to claim 26, characterized in that at least one of the crush blocks is elongated to at least twice its width. 30. The vehicle bumper system according to claim 26, characterized in that the thermoformed component further has a rearwardly extending element formed in the base sheet extending to a channel formed in the face of the beam to assist retaining the energy absorber on the face during the collision of the vehicle. 31. The vehicle bumper system according to claim 26, characterized in that at least half of the crush blocks are less than about 35 mm high. 32. The vehicle bumper system according to claim 31, characterized in that the crush blocks vary in height. 33. The vehicle bumper system according to claim 26, characterized in that the base flange is flexible and bendable, such that the thermoformed component is bendable to mate with the face of the beam despite the difference in shape when it is in an unattached and unstressed state. 34. The vehicle bumper system according to claim 26, characterized in that at least one of the walls of the crush block includes a support which, upon receiving an impact causes the bumper system to move through a stroke, overlapping on itself during the race.