US20210245218A1

US20210245218A1 - Extruded profile produced with rotating shaping dies

Info

Publication number: US20210245218A1
Application number: US17/180,278
Authority: US
Inventors: Mark Jansson Kragh
Original assignee: Reliefed AB
Current assignee: Reliefed AB
Priority date: 2015-07-04
Filing date: 2021-02-19
Publication date: 2021-08-12
Also published as: CN107848182B; EP3317076B1; EP3317076A1; SE1530102A1; CN107848182A; US10875069B2; JP2018523579A; EP3317077A4; WO2017007410A1; CN116572497A; CN107848181A; SE539862C2; US20180193891A1; EP3317077A1; EP3317076A4; US20180207698A1; JP6843777B2; DK3317076T3; SE1530103A1

Abstract

A device and method for designing lightweight, strong, material efficient, extruded and pultruded profiles, profile segments and surfaces produced in profile production with rotating dies creating superior resistance to compression, bending and buckling, higher energy absorption and right strength in the right place, by: varying the thickness along and across the direction of extrusion, making reinforcing patterns varying the profile thickness, and in some cases varying angles and patterns which increases the profile segments/surface resistance against compression, bending and buckling relative to the amount of material used and resulting in the manufacturing of optimized beams and surfaces that have superior properties in terms of strength/weight, stiffness/weight ratio, mechanical energy absorption/weight unit, deformation and natural frequency, thermal transfer capacity, the breaking of the laminar flow, increased/optimized surface for chemical and/or electrochemical reaction etc.

Description

TECHNICAL FIELD

The present invention relates to a new principle to design profiles, profile segments, beams, elements for absorption of kinetic energy and surfaces/panels by varying the wall thickness along (_t)+across extrusion or pultrusions direction, making reinforcing patterns (2, 3), vary the profile thickness (T, t), and in some cases vary, cross-sectional area (_A FIGS. 11, 12, 15.2 angles (10, 11, FIG. 1) and pattern (2, 3, FIG. 1) which raises profile segments/panels resistance to bending, compression and buckling, relative to the amount of material used, enabling optimum performance for the purpose they are to serve, with minimum weight and minimum use of raw materials.
The invention can be done in various forms in a number of different ways for different applications, with various requirements and is applicable to extrusion and pultrusion of plastically deformable materials and material combinations for example metal, metal composite, plastic, plastic composite, wood based composites, clay, rubber or reinforced rubber formed to profile by a process comprising a tool with one or more fixed parts partially predefining the profile's appearance/cross section before the profiles final shape is defined to a fixed or varied cross section when the material passes rotating body can be patterned or smooth and whose position in some embodiments of the invention may vary relative to other bearing surfaces or rotating bearing surfaces in the tool with which they define profiles final shape, whether rotating dies used are patterned or not.

BACKGROUND

With an increasingly stronger need to economize on energy and raw materials, the value of saving on weight in cars, trucks, buses, boats, trains, and not least in airplanes is increasingly actualized.
Materials such as fibre composites, aluminum, aluminum composites, high strength steel etc. have made their entry into the designs traditionally based on steel/iron in the quest to keep the weight down, while requirements for performance, strength, environmental aspects, recycling and safety is increased for each product generation.
Consequently, the value of a kilogram of weightsaving is increased for every year and, of course, this figure varies for boats, cars, buses, trucks, and airplanes.
And commodity prices of light metals, such as aluminum, magnesium, titanium etc. has risen with demand and energy prices, resulting in a quest to minimize unnecessary use of materials in all kinds of beams, profiles and products.
This makes it increasingly important to use the materials in an optimal and “intelligently” way—to make sure the material is placed where it provides maximum desired strength and property and minimize or eliminate the amount of material where it is least useful.
This is because a profile with the same cross-section or appearance all the way often do not qualify for meeting customers product and application requirements regarding design, function and performance particularly in automotive, aerospace, mass transportation, and structural applications.
The traditional methods first manufacturing profiles and then process until varied thickness and/or pattern requires very high costs for processing and machining equipment, which is due cost reasons altogether would exclude processing developed optimized profiles. In addition, such machining result in broken material veining (generating fractural indication weaknesses).

SUMMARY OF INVENTION

An object of the example embodiments of the disclosure is to provide an improved extruded profile. This object is partly achieved by the features of the independent claims.
According to one example embodiment, there is provided an extruded profile having a longitudinal direction X and a transverse direction Y, and manufactured by dynamic extrusion/pultrusion of plastically/thermally deformable material with one or more static array elements with static bearing surfaces which in cooperation with one or more rotating dies whose rotating bearing surfaces completely or partly defines a profile cross-sectional shape that comprises two different thickness values in a longitudinal cross-section and/or a transverse cross-section.
In other words, the profile cross-sectional shape comprises at least two different thickness values in the longitudinal cross-section. In addition, or alternatively, the profile cross-sectional shape comprises at least two different thickness values in the transverse cross-section.
As mentioned herein, further advantages are achieved by implementing one or several of the features of the dependent claims.
By way of example, the difference between a maximum thickness value and a minimum thickness value for at least one cross sectional shape is in the range between 2%-80%. In another example, the difference between a maximum thickness value and a minimum thickness value for at least one cross section is in the range between 4%-50%. In yet another example, the difference between a maximum thickness value and a minimum thickness value for at least one cross section is in the range between 5%-20%.
Typically, the thickness, as seen in the vertical direction Z, is varied for a given width along the transverse direction Y for any transverse cross-section.
In addition, or alternatively, the thickness, as seen in the vertical direction Z, is varied for a given length along the longitudinal direction X for any longitudinal cross-section.
According to one example embodiment, the shape of the transverse cross section is varied for a given length along the longitudinal direction X.
According to one example embodiment, a variation of the thickness for a given width is any one of a linear variation, non-linear variation, and step-wise variation. Other variations are also conceivable depending on the use and installation of the profile.
According to one example embodiment, the profile cross-sectional shape defines a pattern extending in a direction different than the longitudinal direction and the transverse direction.
Typically, although not strictly required, the pattern comprises at least one indentation and at least one projecting region.
According to one example embodiment, the pattern is part of a repetitive pattern extending in the directions of the profile.
By way of example, the at least one reinforced region is at least partly or entirely a diagonal-extending region, a polygon-shaped region such as a circular-shaped region, an elliptic-shaped region, a triangular-shaped region or the like, as seen in the longitudinal direction and in the transverse direction.
According to one example embodiment, the profile comprising at least two different transverse cross sectional shapes along the longitudinal direction X, and at least two different longitudinal sectional shapes along the transverse direction Y.
Typically, the difference between said at least two different thickness values is provided by a variation of the profile thickness in the profile longitudinal direction.
An extruded profile according to the example embodiments as mentioned herein is particularly useful as a vehicle structure profile. By way of example, the profile can be used as an impact beam, impact absorbing beam or the like, such as a bumper impact beam. However, the extruded profile can be used and installed in several different types of structures and systems.
The term “pattern” as used herein may refer to any type of region defined (or obtained) by the dynamic extrusion/pultrusion method as mentioned above, which typically at least partly or entirely defines a profile cross-sectional shape that comprises two different thickness values in a longitudinal cross-section and/or in a transverse cross-section.
It is to be noted that the pattern may sometimes also be referred to as a reinforced region, a reinforced pattern, stiffening pattern, stiffeners, pattern segment or segment, or simply as a pattern.
Typically, although strictly not necessary, the pattern comprises at least one indentation and at least one projecting area.
The material veining obtained during profile creation with rotating dies instead follow the surface of the finished product , resulting in several positive effects:
1. No broken materials veining.
2. Reduced risk of so-called “desquamation” or scaling that occur as a result of friction-temperature extrusion speed because of tensile stresses exceed exceeding the materials 5 tensile strength at the corresponding temperature. Thanks to the lower friction forces in the profiles surface layer occurs radically lower tensile stresses in the profile surface, enabling extrusion in higher speeds without the risk that transverse cracks occurs (ref. scaling “Plastic processing” by Erik Storm, p. 128 publishers Bonniers).
3. Extruded/pultruded materials often have a 15 better material property (higher strength) in the utmost millimeters of the surface and consequently it always results in maximum material performance in the surface.
4. Homogenous material/product characteristics. At regular extrusion/pultrusion, the material gets better strength along the extrusion/pultrusion direction than it gets in the transverse direction, which inhibits product performance. In a profile extruded/pultrudeded with rotary shaping die members the material get more isotropic properties regarding strength and direction.
5. Composites and specially metal composites reinforced with ceramic fibers or powder, can be very difficult to machine and with eliminated or minimized machining the problem decreases.
6. The composite fibers and/or powder settles according material veining and thus provide maximum performance in the desired direction.
By in accordance with the invention utilising rotational shaping members, placing the material on the right place one can achieve optimized profiles, beams and beam segments thus can be made to achieve the desired strength, stiffness, resilience, flexibility, natural frequency, compression resistance and kinetic energy absorption with minimal weight/material consumption.
This applies also to design of products so that they give best possible “crash-management” i.e. is strong on the right place and weak in the right place, so that it can achieve desired deformation order in a beam, which is made possible by making the profiles with different strengths in different places, and that the components are deformed with linear or progressive force to get steady deceleration in the example of a car collision or an aircraft crash, so that the parts are deformed in the desired manner in the right order and absorbs as much kinetic energy as possible, in a manner that protects passengers from unnecessary forces and injuries.
This makes the methodology described in this document particularly useful for bumpers, crash-box (the component that secures the bumper and that absorb kinetic energy in collisions at a certain speed).
The methodology is also useful for optimizing the lamp-posts, sign holders and other elements in the traffic environments, as well as all profiles and beams that are included in some form of load cases.
The method makes it possible to extract the materials and weight saving potential that profile production with rotating dies give after the last development stages and innovations:
The new methodology for the process described in Swedish Patent Application No. 0702659-4 (Apparatus and procedure to start up, control of outgoing material and Process Stabilization in profile manufacturing with rotating dies) by Garry Leil describing how to solve the problems that hindered the industrialization of profile production with rotating dies.
The principle of profile creation with rotating dies have been previously described in various papers and patents and developed in a number of steps including Pierre Hamel (Technical Paper “How to extrude embossed flexible profiles” by Pierre Hamel in Plastics Engineering 15, band 36, No. 6, June 1980 p. 34-35) and the current inventor (pat. SE504300 (C2) and Pat. SE514815 (C2).
Both patent SE504300 (C2) and the patent SE514815 (C2) may be said to describe the procedure for extrusion with rotating dies acc. Pierre Hamel instructions, while patent applications 0702030-8 and 0702659-4 describes new methods and approaches enabling and in some cases is a prerequisite for producing the profiles described in this patent. Production with rotating dies members are possible in all types of pultrusion and extrusion plants, with minimal or no adaptation needs of the facility, including hydraulic metal extrusion lines, screw extruders for rubber/plastic, conformextrusions machines and pultrusion machines, meaning that there is much good industrial capacity built to produce optimized profiles, segments and surfaces designed according to the methodology of the present invention.
As mentioned above, the purpose of the invention is to by optimized design, rationally reduce weight, raw material consumption, energy consumption and emissions in the stage of manufacturing and use the profiles, beams, beam segments and areas having property improving designs and/or thickness variations that utilize the capabilities of rotating dies in a way that conventionally designed profiles, beams and surfaces can not make. This makes it possible to:
1. Get a profile or surface with improved weight/strength ratio=save weight+raw materials.
2. Customize properties.
3. Replace more expensive materials such as e.g. carbon fibre and titanium with aluminum and magnesium (thanks improved better strength/weight relation.)
4. Reduce processing costs and material waste.
5. Improve crash protection in vehicles.
6. Achieve components with improved performance regarding acoustics/vibration.
7. Achieve greater thermal transfer capacity through micro and macro-patterning of profiles.
7. Achieve higher/optimized surface for chemical and/or electrochemical reaction.
The invention relates to a new way to design, lighter, stronger, stiffer material efficient profiles (6,26,) Surfaces (22), beam segments (4), and energy absorbing members (6) and structures (23), with the desired behaviour patterns (7 FIG. 4b ) by variation of thickness and/or pattern which gives improved performance that is achieved by placing the material it does the most good and provide desired performance and desired behaviour, such as on strength, deformation, energy absorption, resonance with etcetera and enables significant savings of weight and raw materials in beams, structures and components that are preferably produced by continuous pressing, called extruding or drawing called pultrusion by plastically/thermally moldable materials (204, 321), for example, metal, composite metal, plastic, composite plastic or rubber pressed to optimized profile (6, 322, 212), optimized beam segment (4, 23) or optimized surface (22) by a process comprising the tool fixed member (206) partially predefining the profile's shape/cross section before the profile shape is defined with a fixed or varied cross section area when material passes rotating dies (210, 318, 304, 310) which can be patterned or smooth and may also can be adjusted (FIG. 18, FIG. 21) and can be combined with other moving members which enables further profile variation (FIG. 22) and whose position in certain embodiments can vary the thickness and pattern (FIG. 303).
Different embodiments and applications of the invention, makes it possible to improve the weight/strength ratio up to and in some cases over 50% in actual components with equal or better performance and with optimized characteristics (for example. deformation behaviour, natural frequency, etc.), enabling it to make better and more fuel-efficient cars, vehicles, airplanes, boats, with maintained safety and stronger structures that are lighter and less expensive.
Explanations of context, nomenclature and used words in patent:
Optimized profile With optimized profile it is meant a profile manufactured with dynamic extrusion or pultrusion manufactured with reinforcing patterns (18, 19, 20, 21) and/or goods variation (_t, _A) that gives the optimized profile a higher strength/weight ratio than a corresponding profile with the same amount of material and cross layout without reinforcing patterns and goods variation has. The patterns of the optimized profile can be customized to achieve maximum strength, stiffness, ability to absorb kinetic energy, be resistant to buckling, compression, have different properties in different directions etc.
Optimized surface: With optimized surface it is mean an essentially flat profile (see FIG. 8.) manufactured with dynamic extrusion or pultrusion with reinforcing pattern and/or goods variation which gives the optimized profile a strength/weight ratio and buckling resistance that is higher than a corresponding surface with the same amount of material and cross section layout without reinforcing patterns and goods variation has. The optimized surface patterns can be customized to get maximum strength, stiffness, ability to absorb kinetic energy, buckling resistance, compression resistant, have different properties in different directions, etc. The optimized surface can also be bent or profile into a profile which can have patterns on either in or outside or both inside and outside (if the optimized surface as the starting substance has pattern/ribs on both sides). In this way one can achieve optimized beams and profiles that are both open, half open (U profile) and closed (hollow), with relatively simple and inexpensive tools without the die core portion (see FIG. 16 pos 203). This is for three reasons:
1. Dies (see FIG. 18 item 206) with core member (211) is expensive and more difficult to manufacture than dies without core portion (see FIGS. 11, 12, 13) at the same time as they are sensitive to fatigue.
2. If the volumes are low and you want to have patterns on the inside of the profile, it is much easier and cheaper to make a tool with a rotating shaping member (FIGS. 11, 12, 13) and then roll form or bend the optimized surface to the desired profile shape.
3. If you want optimizing pattern around all sides of for example a rectangular profile it will be very difficult to make a profile creating die with four rotating dies that shall be able to cope with the forces when extruding for example aluminum in long batches. If pattern on the inside and outside around, the only option is to use an optimized surface with pattern on both sides (see FIG. 12 pos. and 29 FIG. 13, pos. 30), made in a die without core portion, that later can be bent to the desired shape. This way hollow profiles with optimising pattern all around, on in and outside can be produced.
Extrusion
Procedure in which a material under pressure is pressed through a profile shaping tool (also called die) with hole(s) that defines the outgoing materials cross-section and appearance. Extrusion can be performed in most metals, metal matrix, thermal resins, some fibre composite mixtures, ceramics, clay, rubber, candy, food (e.g. pasta, etc.).
Pultrusion
In contrast to the extrusion means the profile drawing. Pultrusion generally means that a continuous fibre bundle impregnated with liquid resin drawn through a heated die, but pultrusion is also used for shaping metal tubes and profiles. Resin impregnation occurs in a resin bath. The most common material is glass-reinforced unsaturated polyester. Other core epoxy resins and PolyUrethane are used depending on the application. Often used fibrous material in the form of woven or felt fabric, resulting fibre beam to achieve strength in the transverse direction. Pre-preg fibres (Fibres that are pre-impregnated with resin), can also be used.
Dynamic Extrusion
Procedure in which a material under pressure, is pressed through a tool/die with rotating forming members/dies that can give the profile a varied cross-section and/or appearance in the form of e.g. patterns on one or more surfaces and dimensional changes in cross-sectional area and or goods thicknesses. The rotating shaping die members can be with pattern/variation as well as smooth or a combination of both. The rotating shaping die members can be raised and lowered independently of other cycles in the process.
Dynamic Pultrusion:
Procedure whereby one/several profile(s) drawn through a die/tool with rotating forming members/dies that can give the profile(s) a varied cross-section and/or appearance in the form of e.g. patterns on one or more surfaces and dimensional changes in cross-sectional area and or goods thicknesses. The rotating shaping die members can be with pattern/variation as well as smooth or a combination of both. The rotating shaping die members can be raised and lowered independently of other cycles in the process.
Die: Generally, the name used by professionals for profile production tools.
Rotating die: Rotating profile-shaping member/organ of the tool for dynamic extrusion/pultrusion
Process collapse/breakdown: Generic name for the failure of the start up of extrusion/pultrusion or problems at billet exchange, production, etc. that results in production stop. The high proportion of process-breakdowns has made the industrialization of the production of profile with rotating dies very problematic.
Pressure drop: Reduction of pressure by the tool is a result of area-reduction, plastic exemplary work and friction. At metal extrusion converted large amounts of energy to heat, as a result of pressure. By “pressure drop balancing”—making adjustments to the pressure drop in the tool, the outgoing material get the same speed in all parts.
Flow imbalance: Imbalance means that the outgoing material will or want to come out with higher or lower speed at certain parts of the profile cross-section. A profile extruded in a tool with the imbalance may be less resistant (due to internal tensions), tend to dent or bend and at the extrusion with rotating dies result is often the process breakdown.
Bearing Surface: The surface of an extrusion die in the smallest cross section that the extruded material is forced through under pressure and thus constitutes the surface to finally define the profile cross-section and appearance.
Static Bearing Surface: A bearing surface the extruded material is forced to pass at a relative speed of outgoing profile speed, because it is static, so that means there is a speed difference between the static bearing surface and the extruded material, resulting in a lot of friction and heat. By regulating the length of the bearing surfaces can regulate the total amount friction and thus the pressure and speed of the outgoing material.
Rotating Bearing Surface/Rotating profile shaping surface: A rotating bearing surface is a surface of the rotating die/member that defines the profile cross-section, making patterns possible as well as wall-thickness variation. A rotating bearing surface in general generates much less resistance/friction against the flowing material than a static bearing surface, which previously has created major problems with the imbalance between the different parts of the profile cross-section, which is defined by the rotating bearing surfaces and the parts that are defined by static bearing surfaces. This has often resulted in the process breakdown at start up. At profile manufacturing with use of present inventions device and method the problems with this, is radically reduced, through the gripping, steering and pulling of the profile in the right direction already in the tool. If you lift the rotating bearing surfaces at start up and let the gripping, steering puller go into the tool, elimination of deviating profile that can cause process failure is achieved.
Pre-Bearing/Pre-Bearing Surface: The surface area that the extruded material passes just before it comes to the rotating die/forming member and its rotating bearing. The pre-bearing brings down the material cross section so much so that the subsequent rotating die wont have to take up unnecessarily large forces from the extruded material. Pre-bearing has in combination with preceding shape in the die upstream a central role for control and/or redulation of material flows through the die.
Puller/Profile Puller: At the extrusion of metal profiles, it is customary that when one has squeezed out enough profile to reach the ordinary puller (usually 3-7 meters from the die) to stop extrusion, grip profile and then pull the profile and then re-start the extrusion. Some modern plants use dual-pullers, which means increased productivity and reduction of the number of stops and downtime.
Griping & steering pulling device In order to be able to make a plurality of the profiles shown in the drawings, it requires a special device a so called gripping & steering puller and procedure shown in the patent application 0702659-4. The gripping steering pulling device, grip, steer and pull the profile long before ordinary puller, which is too far from the die since the majority of the profiles exhibited here requires direct control and stretching after or before leaving the tool. In some cases, the gripping, steering puller go all the way into the tool and grip and pull the material before it leaves the die (see FIG. 17 A). Gripping steering puller enables efficient, repetitive, serial production with rotating shaping bearing surfaces during extrusion of thin profiles, with great variety of goods thickness, asymmetric profiles, with deep tread depth,“Weak” profiles (profile with low intrinsic stiffness) and weak profile segments (segments with low intrinsic stiffness), “flat” broad segments (see FIG. 8) who usually like to follow around the rotating die due to adhesion.
Griping puller can eliminate or minimize process breakdowns and enable start-up and ongoing efficient production of extruded profiles with rotating dies, which would otherwise be unthinkable due several factors:
I the adhesion between the rotating bearing and extruded material.
II friction difference between the braking friction of rotating bearings and static bearings (rotating bearings brakes far less than static bearings).
III absence/lack of static bearings that give directional control to outgoing profile (rotating bearings have a radius and are consequently, not so good at steering the profile straight, they tend to steer the profile to follow the rotating bearing radius, if the adhesion between the rotating bearing and outgoing material occurs).
IV low intrinsic stiffness, thin profile,
V deep patterns relative wall thickness and steep angles on the patterns.
In varying cross sectional area.
The present invention enables a variation of the thickness and tread depth, in reality, by taking into account factors such as variation of the pressure drop and the outlet rate, both of which vary when varying the outlet area/cross section of the profile:
A reduced outlet area=increased pressure drop and at constant speed on the feeding of material into the extrusion/pultrusiondie the result is a higher outlet speed and potentially big problems with increased temperatures and intermittently varying outlet speed of profile: for example, a halved outlet area result in doubled outlet speed at continuous feeding of extrusion material, which more or less inevitably leads to large process problems with varying quality on the basis profile and is likely to result in process breakdown. This is because the outbound profile must rapidly accelerate and decelerate, giving very large varied loads between back pressure and tension loads of outgoing material directly on the tool's outlet after the die bearings, where the material is at its warmest and softest and most dependent on a continuous stretch/steering—resulting in that the profile easily lose control and stick to the rotating die and plugs the tool outlet, the process of breakdown is a fact.
Another aspect is the dependence between the maximum extrusion and cross-sectional area of a profile and the thickness of the profile extruded/pultruded, which is particularly sensitive in ingot fed extrusion lines is the so-called extrusion ratio very crucial (extrusion ratio=the materials area from ingots in relation to the outgoing profile area). A high extrusion ratio reduces the maximum discharge rate of extruded/pultruded profile due to, among other things heat build up and flaking. Flaking is a phenomenon that occurs when you try to extrude/pultrude in high speed and outgoing profile has problem with holding together, due to the forces of friction between the outgoing profile and bearing surfaces and area reduction, is exceeding or approaching outgoing materials maximum speed and cracks which generally goes across extrusion/pultrusion direction. An increased area reduction results in other words, in increase of the risk of scaling, while speed is increased on the output profile, if one does not take this into account. In other words, feeding material into the extrusion/pultrusion tool result in the profile goes faster when there is a reduced cross-sectional area (as it would be wise to rather have a reduced exit speed to avoid cracking, flaking and/or overheating of outgoing material. This is solved, according to the present invention, by varying the speed/volume per unit time of material feeding extrusion/pultrusion die in order to either allow such constant outlet speed as possible on the outgoing profile, or decreases the exit speed, to avoid risk of flaking/overheating of outgoing material, when the smaller profile area is run.
Naturally, this includes synchronizing of puller device that holds the profile tensioned. The application of the present invention is applicable to all types of extrusion plants, with minimal or no adaptation needs of the facility, including hydraulic facilities metal extrusion, screw extruders for rubber/plastic and conformextrusions facilities, etc.

BRIEF DESCRIPTION OF THE DRAWINGS

With reference to the appended drawings, below follows a more detailed description of embodiments of the disclosure cited as examples.

In the drawings:

FIGS. 1, 1A and 1B schematically show an example embodiment of an extruded profile according to the disclosure in the form of a bumper beam;

FIG. 2A shows an example embodiment of the extruded profile in FIG. 1 and FIGS. 1A-1B;

FIG. 2B shows cross section of the example embodiment of the extruded profile in FIG. 1 and FIGS. 1A-1B;

FIG. 3A schematically shows another example embodiment of the extruded profile;

FIG. 3B shows a cross section along A-A and B-B in FIG. 3A;

FIGS. 4A, 4B and 5 schematically show various modes of an example embodiment of an extruded profile according to the disclosure in the form of a bumper beam;

FIGS. 6 and 7 schematically show various example embodiments of an extruded profile according to the disclosure;

FIG. 8 schematically shows an example embodiment of a pattern of an extruded profile according to the disclosure;

FIG. 9 schematically shows an example embodiment of an extruded profile according to the disclosure in the form of a framework;

FIGS. 10, 10 A-A, and 10 B-B schematically show various example embodiments of an extruded profile according to the disclosure;

FIGS. 11-15 schematically show various example embodiments of an apparatus and method for manufacturing an extruded profile according to the disclosure;

FIGS. 16, 17A-17B, 18, and 19A-19C schematically show further details of various example embodiments of an apparatus and method for manufacturing an extruded profile according to the disclosure;

FIGS. 20-23B schematically show further details of various example embodiments of an apparatus and method for manufacturing an extruded profile according to the disclosure.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

The present invention will in the following be described in various embodiments with reference to the accompanying drawings which of example show preferred embodiments of the invention, the invention is not limited to those in the drawings and descriptions exemplary embodiments, but
can by a technician be performed in other ways and with more combinations based on the description and appended claims with variations of profiles, profile segments and surfaces with varied patterns and thicknesses and profile segments and profiles with different configurations that look different from those in the exemplifying drawings on exhibited examples. The invention is comprised of all the possible combinations which can be achieved within the patent claims.
FIG. 1 shows the optimized profile segments of a bumper beam (6) with optimized patterned segments (4) according to the present invention, where the optimized segment (4) get gained increased compression/buckling and dent resistance from transverse (2) and longitudinal (3) reinforcements with height (_t) according to a pattern that provides enhanced thickness (T) in relation to the thin goods (1) and where the optimized segment (4) transforms into the corner segments (5) are angled (10, 11) together with the along and transverse reinforcements to control the deformation at a compression where corner segments (5) are forced together and in order to obtain the maximum energy absorption, with steady force at the crash without beam segment 5 suddenly collapses and give in. By this, the segment of FIG. 1 gives a light, strong bumper beam that provides uniform deceleration with high energy absorption capacity without sudden collapse.
As illustrated in the figures herein, for example FIGS. 1, 1 a and 1 b, there is provided one example embodiment of an extruded profile 6. For the purpose of facilitating the description, the extruded profile is here described in relation to a bumper beam. However, other types of profile and beams are readily conceivable such as vehicle structure profiles.
The extruded profile has a longitudinal direction X, a transverse direction Y and a vertical direction Z.
The extruded profile is manufactured by dynamic extrusion/pultrusion of plastically/thermally deformable material with one or more static array elements with static bearing surfaces which in cooperation with one or more rotating dies whose rotating bearing surfaces completely or partly defines a profile cross-section, in particular a cross-sectional shape.
FIG. 1a shows part of a transvers cross section of the profile shape. As shown in e.g. FIG. 1 a, the profile cross-sectional shape comprises two different thickness values in the transverse cross-section.
FIG. 1b shows part of a longitudinal cross section of the profile shape. Further, as shown in e.g. FIG. 1 b, the profile cross-sectional shape comprises two different thickness values in a longitudinal cross-section.
The figures illustrate an extruded profile having a profile cross-sectional shape that comprises two different thickness values in a longitudinal cross-section and two different thickness values in a transverse cross-section. However, it is to be noted that the extruded profile may only have a profile cross-sectional shape that comprises two different thickness values in the longitudinal cross-section. Alternatively, the extruded profile may only have a profile cross-sectional shape that comprises two different thickness values in the transverse cross-section.
In addition, it is to be noted that the cross-sectional shape may of course include any other number of different thickness values. Thus, it is only required that the profile cross-sectional shape comprises at least two different thickness values in the longitudinal cross-section and/or at least two different thickness values in the transverse cross-section. That the extruded profile has a profile cross-sectional shape that comprises at least two different thickness values in the longitudinal cross-section and at least two different thickness values in the transverse cross-section can be readily appreciated from the various figures, showing e.g. a linearly varied thickness of the cross sectional shape, a non-linearly varied thickness of the cross sectional shape or a multiple step-wise varied thickness of the cross sectional shape.
Turning again to FIG. 1 a, the transverse cross-section extends in the transverse direction Y and in the vertical direction Z. Furthermore, the transverse cross-section comprises at least two different thickness values T1 and T2, as seen in the vertical direction Z. FIG. 1a shows a part of a transverse cross-section of the profile in FIG. 1. In this figure, the extruded profile has been manufactured to form a profile with a transverse cross section having at least a first thickness value T1 and a second thickness value T2. In some example, the first thickness value T1 may correspond to a maximum thickness value and the second thickness value T2 may correspond to a minimum thickness value.
Turning again to FIG. 1 b, the longitudinal cross-section extends in the longitudinal direction X and in the vertical direction Z. Furthermore, the longitudinal cross-section comprises at least two different thickness values T3 and T4, as seen in the vertical direction Z. FIG. 1b shows a part of a longitudinal cross-section of the profile in FIG. 1. In this figure, the extruded profile has been manufactured to form a profile with a longitudinal cross section having at least a first thickness value T3 and a second thickness value T4. In some example, the first thickness value T3 may correspond to a maximum thickness value and the second thickness value T4 may correspond to a minimum thickness value.
By way of example, the difference between a maximum thickness value Tmax and a minimum thickness value Tmin in a cross-sectional shape is in the range between 2%-80%. In another example, the difference between a maximum thickness value and a minimum thickness value for at least one cross section is in the range between 4%-50%. In yet another example, the difference between a maximum thickness value and a minimum thickness value for at least one cross section is in the range between 5%-20%.
Further, as shown in figure la, the thickness, as seen in the vertical direction Z, is varied for a given width Ly. In this example, the variation of the thickness is varied in step-wise fashion. However, the thickness can be varied in several different ways. That is, a variation of the thickness for a given width can be any one of a linear variation, non-linear variation, and/or step-wise variation. Other variations are also conceivable depending on the use and installation of the profile, which are further illustrated by the figures hereinafter.
Analogously, as shown in FIG. 1 b, the thickness, as seen in the vertical direction Z, is varied for a given length Lx. In this example, the variation of the thickness is varied in step-wise fashion. However, the thickness can be varied in several different ways. That is, a variation of the thickness for a given length can be any one of a linear variation, non-linear variation, and/or step-wise variation. Other variations are also conceivable depending on the use and installation of the profile, which are further illustrated by the figures hereinafter.
In some design options, as shown in various figures herein, the thickness, as seen in the vertical direction Z, is varied for a given width Ly along the transverse direction Y for any transverse cross section.
According to one example embodiment, the shape of the transverse cross section is varied for a given length along the longitudinal direction X.
Turning again to e.g. FIGS. 1, 1 a and 1 b, the profile cross-sectional shape defines a pattern 2, 3, 400 extending in a direction different than the longitudinal direction and the transverse direction. Further examples of patterns or so called reinforced regions extending in a direction different than the longitudinal direction and the transverse direction are illustrated in e.g. FIGS. 2A, 2B, 3A, 3B, and FIGS. 6-9.
Typically, although not strictly required, the pattern comprises at least one indentation and at least one projecting region.
According to one example embodiment, the pattern is part of a repetitive pattern extending in the directions X, Y and Z of the profile, see e.g. FIGS. 1, 1A, 2A, 2B, 3A, 3B, and FIGS. 6-9. The pattern as illustrated herein typically provides for an improved strength compared to non-patterned profile.
By way of example, the pattern is at least partly or entirely a diagonal-extending region (see FIGS. 1, 1A and 1B), a polygon-shaped region such as a circular-shaped region (FIG. 7), an elliptic-shaped region, a triangular-shaped region (FIG. 8) or the like, as seen in the longitudinal direction and in the transverse direction.
According to one example embodiment, the profile comprising at least two different transverse cross sectional shapes along the longitudinal direction X, and at least two different longitudinal sectional shapes along the transverse direction Y, which may be gleaned from FIG. 10 although only one cross section and one longitudinal section are shown by FIGS. 10 A-A and 10 B-B.
In addition, or alternatively, the difference between the at least two different thickness values T1 and T2 is provided by a variation of the profile thickness in the profile longitudinal direction X.
As illustrated in the various figures herein, the variation in thickness can also be varied in both the transverse direction Y and the longitudinal direction X.
In the following description in conjunction with the FIGS. 2-10, further example embodiments are provided that may incorporate any one of the features, aspects or examples as described in relation to FIGS. 1, 1 a and 1 b above.
FIG. 2A shows an example of an optimized bumper beam seen from the top with front (14), back (13) and optimized top (4) visible.
FIG. 2B section A-A is a cross-section of the bumper beam (FIG. 2A), which showing how the optimized beam segments (4) are bent inward center at a collision when the front (14) of the beam is pressed against the back (13) which results in the optimized segments are pressed together completely (bent toward the beam middle in direction of the arrows, so the optimized segments is double- folded between the rear segment (13) and the compression preventing segment (15) whose depth (16) together with the double-folded optimized segments (4)patterned thickness (T) eliminates the bumper beam will completely flat and weak, at a hard collision, which can save lives.
FIG. 3A shows a side bumper beam with optimized segments (4), front (14) and back (13).
FIG. 3B shows the section A-A: B-B, the pattern provides a cyclical goods variation with low consumption of material giving a high resistance against bending, buckling, compression and dent.
FIG. 4A shows the unstressed bumper beam (6) FIG. 4B shows the bumper beam exposed to the load (4F) a 2 cm wide area across the beam front and is attached to the ends at the fixing points (F, F, F,F) to the so-called crash boxes.
FIG. 5 shows the same collision simulation in FIG. 4b and one can see how the optimized beam segments (4) absorbs energy by bending inwards (17) with an even radius, without collapsing, which provides an optimum combination of strength, energy absorption, controlled deceleration without peaks and dips while the beam weighs 35% less than a beam without optimized segments with similar construction.
FIG. 6 shows an example of beam segments optimized for low weight combined with resistance against compression/dent, and stiffness of the beam segment without greater priority to mechanical energy absorption at deformation. It shows how the point load (Fk) distributed and spreading through the transverse (18), diagonal (19 and longitudinal (20) reinforcements. This segment is essentially flat since it is optimized for stiffness and strength, energy absorption has not been prioritized maximum (-Unlike the example of bumper beam in FIG. 5).
FIG. 7 shows an example of another embodiment of the a flat, patterned, beam segments, with goods variations in form of circular (21) reinforcements, transverse reinforcements (18) and a longitudinal reinforcement (20).
This beam segment gets a slightly “softer” characteristic in compression by the circular reinforcements than beam in FIG. 6 has. The transverse reinforcements (18) combined with the longitudinal reinforcement (20) also gives a different characteristic of the load coming on narrow space or the point at k2 than the characteristic behaviour at the point load at point FK1 become: the transverse reinforcements (18) form together with the longitudinal reinforcement (20) and the corner segment (5) a very compression-resistant region that allows beam segment being “harder” against point loads at k2 than at FK1, thus varying patterns and combinations of reinforcements offers new, unique capabilities to a rational way to of producing lightweight beams, segments and products with tailored properties for different applications and uses.
FIG. 8 shows an example of how to design a pattern, to obtain a surface (22) that is light, stiff and resistant to buckling when loads to the surface normal. The surface could be used to make the floors of an aircraft significantly lighter or to replace flat profiles or panels in ship decks, car decks, general construction, trucks, trains, trains, buses, consumer products etc. The uses for lightweight surfaces with good rigidity are diverse not only due to weight, but also due to possibility of reducing raw material consumption and affect the natural frequency, stiffness, etc. With “Enhancement pattern” that one achieves through the patterns given by hollows in the rotating dies body (210B FIG. 18) in the extrusion or pultrusion process (see FIG. 18), can be added relatively low cost and provide surface “sheets” which has significantly higher performance combined with low weight and reduced raw material cost, than would otherwise be possible.
FIG. 9 shows an example of a beam segment that is reminiscent of an old classic so-called “latticework”, which usually is made by punching, milling, water cutting, or assembly of separate parts to high cost. By instead calculating the ideal the cross section of each segment (23A, 23B, 23C, 23D, 23E) and let the cross section of each segment vary as load varies from the points where they meet (23A, 23D) to their center (23B, 23E) to optimize the beam segment and beams, is achieved in a single step, a very weight optimised segment in a single process step. If you choose to do “simple” beam segment according to FIG. 9 it is possible to merge multiple identical or different segments to complete a square, triangular or other shape of the profile. The segment is also very appropriate to make a light and strong waist for the I-beam.
When joining multiple segments, Friction Stir Welding is an appropriate method, since it provides joint without tensions or weakening defects in material micro-structure, including materials with extremely small crystalline in the size of 1μ able to maintain their properties relatively intact at FSW. Through additionally process removing material (24) which is not maximum effective for segment strength, you can at an extra cost achieve further improved strength/weight ratio of beams and segments that don't need to be covered. This processing may conveniently be done by water jet, which is relatively inexpensive, efficient and do not produce changes in the structure of materials from heat generation or tools or contamination cracking from vibration and cutting forces.
To succeed with an extruded or pultruded so called truss segment or truss profile, you should take attention to creating a cross-sectional area (here exemplified with cut marks 25A, 25B, 25C and 25D) transverse profile that is substantially the same in pattern cycle (one revolution of the rotating shaping device/die) so that the profile strive to get out of uniform speed of extrusion/pultrusion tool. If the variations on outgoing cross-sectional area big and quickly arise a pulsation in a metal extrusion line could mean that every billet FIG. 16 (204) does not means a load cycle for the extrusion line, but several hundred load cycles, which would soon lead to fatigue. Moreover, it would be very difficult to get good a quality profile.
That is why it advisable to if the end product is a very optimized beam segment or profile, so that the end result is a profile with fast, cyclical, diversified, cross-sectional area variations to making the areas of compensation of the areas to be machined away (24), so that the extrusion/pultrusion has a process in terms of simple profile to do with the relatively even cross sectional area along the profile, which works well in process and allows for greater variety in material thickness (_t). Then, when the area-compensating areas (24) is machined away, it is a very light, strong and rigid profile/segment that have good quality and can be produced with a low proportion of scrap and low bearbetnigs costs.
FIG. 10 shows an example of a profile extruded in one step with 2 optimized beam segment of the type shown before in FIG. 9, with the side segments 27. FIG. 10. This profile can either be made in one step by pultrusion or extrusion with two rotating shaping dies (see FIG. 18) or by joining 2 pcs optimized beam segments (23) with 2 “Normal” segments (27).
In FIG. 10 A-A you can clearly see how the pattern vary thickness and how to use it.
In FIG. 10 B-B and its partial enlargement, one can see how pattern involves a repetitive variation (212) of thickness as a result of the pattern of the rotating shaping dies (see FIG. 18).
In FIG. 11 is shown how one can vary the thickness on an optimized profile (28), by varying the rotating die position, relatively static bearings.
In FIG. 12 is shown how a profile (29) with the pattern both sides are given varying thickness, which varied and cessation patterns, by raising and lowering the rotating dies (110).
FIG. 13 shows how to make a “Zic-Zac” profile (30), by controlling the material in sometimes one and sometimes other direction with the rotating dies.
This provides a profile which has very special properties: it is flexible and weak to bending, while being very stiff and resistant to compression crosswise.
In FIG. 14 has a profile segments acc. FIG. 13 been used as waist during extrusion of an I-beam (32) which can thus be given unique characteristics, it is easy to see how the rotating dies (33, 34) is essentially giving a profile with constant cross-sectional area where the area average A1, A2, and A3 is in principle the same, even though the profile has a “pleated” waist. This allows the extrusion process to be smooth, with a constant area of cross section results in a constant material flow through the tool which gives low pulsations in terms of speed, power and pressure in both billet, tools, bearings and extrusion line.
In FIG. 15 is shown how to vary the cross-sectional and pattern along an imaginary product (35), to be different properties at different locations.
FIG. 16 Displays overview with complete extrusion line provided with gripping & steering puller device (230) complete with stretching device (231), where the rotating dies (10) are in their external positions so that the gripping & steering puller (230) can go right into the die (6) and where the gripping & steering puller (230) is ready to take Receive/embrace, grip, pull and steer outgoing material from die and steer/pull it up to the ordinary gripper (213) and puller (214).
FIG. 17A+17B shows how the device and method interact to provide a stable start-up:
FIG. 17A shows the puller device is ready for process starting with gripping & steering puller (230A) inside the die between the rotating dies (210A), ready to grip, steer and pull outgoing material before it may deviates and cause process breakdown.
FIG. 17B shows how the gripping & steering puller (230B) has gripped the profile and pulls it in the desired direction, while rotating dies (10B) has gone into production mode and started designing outgoing material before it can deviate and cause process breakdown. In order to be able to produce several of those in the preceding preferred profiles with thin materials, patterns and/or varying thickness, it is generally necessary to do it according to 17A+17B to manage start up.
In order to obtain optimal material performance and as little scrapping as possible, it is advisable to avoid stopping for a re gripping of profile, this is achieved according to FIG. 19 A-B-C:
FIG. 19A shows how the gripping & steering puller (230A) has entered in the extrusion press past the front plate and the support plate all the way into the extrusion die (206) ready to grip, steer and pull outgoing materials in the right direction long before extrusion plant's ordinary puller (14 a) and ordinary gripping device (13 a) can do it.
FIG. 19B shows how the gripping & steering puller (30B) has grabbed and takes the output material and goes through ordinary gripping device (213 b) so that ordinary puller (14 a)is able to take over when outgoing material reached regular grippers/puller.
FIG. 19C shows how the gripping puller has pulled out outgoing materials to the ordinary gripping device 213C which thereby able to grip the profile which can thus stretched-controlled by ordinary puller (214 c) start pulling in the outbound profile—without manual intervention, stop interruptions or risk for process breakdown caused by deviating outgoing material.
Gripper-puller (230C) has released profile and moved in sideways before the next startup or before billet exchange where it can ensure that the profile is stretched-drawn at cutting of extrusion lines that lack dual ordinary pullers.
FIG. 20 shows optimized profile (322) with pattern on inside, made by rotating dies (310), sitting in the core portion of the tool. By using movable bearing (318) enabling further opportunities to optimize the thickness and pattern. One can also see how the combination of half-loered bearing (318 b) and completely raised rotating die (304 b) results in a hollow section with the patterned inside and smooth outer surface (22 c) thereof 318 b+304 b=322 c.
FIG. 21 shows how to produce optimized profiles with varied patterns by varying the position of rotary dies (4 a, 4 b) relative to the adjustable bearing (18 b).
FIG. 22 shows how to vary the thickness and pattern (322 a, 322 b, 322 c) at extrusion of hollow section (322) by varying the position of rotary dies (4 a, 4 b, 4 c) and adjustable bearings (18 a, 18 b). This can of course, also be carried out during extrusion of non-hollow sections.
FIG. 23 shows a third embodiment of the invention where varying the thickness of the outgoing profiles, by varying the bearings (313) position.
FIGS. 23a and 23b shows the relationship between the bearings length (314 a, 314 b) and profile thickness (315 a, 315 b) kept reasonably constant at varied thickness, by allowing static bearing surface in fixed tool part cooperating with the bearings variable bearing length—which is important to get the balance flow and stable process.
By the thickness varied over profile/beam segments length, regardless of the rotating shaping cycle entities (which consist of a rotation), so you get maximum strength on the part of beam/the profile which is subjected to the greatest loads.
This is achieved by the/the rotating shaping units (110 FIG. 11+12+13+15, 210 FIG. 16, 18, 304 FIG. 21, 21, 22) is raised and lowered so that you get a variation in the average profile cross section area here called delta A (_A) corresponding by raising or lowering the rotating die units. In this way one can ensure that the beam cross-sectional area and strength is tailored to the needs and the load each portion of a beam or profile becomes exposed to. This is essential since most beams, profiles and profile segments are exposed to various major load at different locations and usually dimensioned the entire length after the point or piece of beam/the profile which is subjected to the greatest loads and thus becomes automatically oversized in other parts.
The disclosure also covers all conceivable combinations of the described aspects, variants, alternatives and example embodiments of the disclosure.
Furthermore, the disclosure is not limited to the aforesaid aspects or examples, but is naturally applicable to other aspects and example embodiments within the scope of the following claims.

Claims

1. A tool configured to form, by dynamic extrusion or pultrusion of a plastically and/or thermally deformable material, a profile having a longitudinal direction and a transverse direction, the tool comprising:

one or more static array elements having static bearing surfaces; and

one or more rotating dies having rotating bearing surfaces,

wherein the static bearing surfaces and the rotating bearing surfaces cooperate to define a cross-sectional shape of the profile, and

wherein each of the rotating bearing surfaces has a bearing profile that is configured to provide the profile with two different thickness values in the longitudinal direction and in the transverse direction.

2. The tool according to claim 1, wherein the tool is configured to provide the profile with a variable thickness in a vertical direction for a given width along the transverse direction for any transverse cross section of said profile.

3. The tool according to claim 1, wherein the tool is configured to provide the profile with a shape of a transverse cross section that is varied for a given length along said longitudinal direction.

4. The tool according to claim 1, wherein the difference between said at least two different thickness values is provided by a variation of the profile thickness in the longitudinal direction of the profile.

5. The tool according to claim 1, further comprising means for varying the location of the rotary bearing surfaces to provide the profile with sections having different cross-sectional areas.

6. The tool according to claim 1, further comprising means for varying the position of the static bearing surfaces to provide the profile with sections having different cross-sectional areas.

7. The tool according to claim 1, wherein the rotating dies can be raised or lowered during operation of the tool.

8. The tool according to claim 1, wherein the tool is configured to provide the profile with profile segments extending in a direction different than the longitudinal direction and the transverse direction.

9. The tool according to claim 8, wherein the profile has variation of 2 sides of the profile segments.

10. The tool according to claim 8, wherein several profile segments have variation.

11. The tool according to claim 1, wherein the tool is configured to provide the profile with a planar profile surface with variation and that is bent to a desired shape.

12. The tool according to claim 1, wherein the tool is configured to provide the profile with a flat profile surface with variations on both sides and that is bent to a desired shape.

13. The tool according to claim 1, wherein the one or more rotating dies comprise two similar rotating dies on each side of the plastically and/or thermally deformable material so as to provide the profile with a uniform cross-sectional area.

14. The tool according to claim 1, further comprising one or more movable bearing inserts.

15. The tool according to claim 14, further comprising a pre-bearing configured to align with and form an extension to a bearing when the one or more movable bearing inserts are in an outer position, so that a bearing length increases when a thickness of the profile thickness increases.

16. The tool according to claim 15, wherein the one or more rotating dies are raiseable or lowerable, and wherein the pre-bearing is raiseable or lowerable.

17. The tool according to claim 1, wherein the tool is configured to vary a speed and/or volume per time unit with which an input amount of material is fed to the tool so as to provide a constant outlet speed as possible on the output profile, or decrease a discharge rate, to avoid risk of flaking and/or overheating of outgoing material, when a smaller profile area is run, thereby synchronizing the input amount of material with an amount of material necessary to vary outgoing cross-sectional area and thickness of the profile.

18. The tool according to claim 1, wherein said profile is any one of a vehicle structure profile or an impact absorbing beam.

19. The tool according to claim 1, wherein the bearing profile comprises a surface pattern or a varied radius.

20. The tool according to claim 19, wherein the surface pattern forms a repetitive profile pattern extending in the longitudinal direction of the profile.