DE102017218797A1 - Strive for an adaptive crash structure, adaptive crash structure, vehicle, method for adapting at least one adaptive crash structure and method for producing a strut - Google Patents

Abstract

A strut (1) for an adaptive crash structure (2) of a vehicle has an outer wall (3) which encloses a cavity (4). The strut (1) has at least two electrodes (5) which protrude into the cavity (4), wherein the electrodes (5) are opposite and each electrode (5) with a power source (6) is connectable. The strut (1) has a powdery material (7) which is arranged within the cavity (4), wherein the powdery material (7) by means of a current flow (8) between the two electrodes (5) is solidifiable (15).

Description

The present invention relates to a strut for an adaptive crash structure with the features of claim 1, an adaptive crash structure having the features of claim 7, a vehicle having the features of claim 9, a method of adapting at least one adaptive crash structure according to claim 11 and a method for producing a strut with the features according to claim 13.

Adaptive crash structures serve to adapt crash characteristics of vehicles. This is especially advantageous when an accident can not be avoided, because the adaptation vehicle occupants can be better protected. However, these adaptive crash structures are complicated and expensive to manufacture and in the control.

Out DE201410001865 B3 An adaptive crash structure for a vehicle is known which has a movably mounted front end. The front end is connected via a rotary joint and a cable system rotatably connected to a body element.

Out DE201310204896 A1 An adaptive crash structure for a vehicle is known. In this case, an elastic foam is arranged in a measuring volume of the adaptive crash structure. The measurement volume is compressed in an impact before other structural elements of the adaptive crash structure.

The present invention is based on the object of the present invention to provide an improved way to create an adaptive crash structure for a vehicle and to adapt it during an accident. This possibility should be inexpensive and easy to produce.

The present invention proposes an adaptive crash structure strut according to claim 1, an adaptive crash structure according to claim 7, a vehicle according to claim 9, a method for adapting at least one adaptive crash structure according to claim 11 on the basis of the aforementioned object and a method for producing a strut according to claim 13. Further advantageous embodiments and further developments emerge from the subclaims.

A strut for an adaptive crash structure of a vehicle has an outer wall that encloses a cavity. The strut has at least two electrodes which protrude into the cavity, the electrodes facing each other and each electrode is connectable to a power source. The strut comprises a powdery material disposed within the cavity, wherein the powdered material is solidifiable by means of a current flow between the two electrodes.

An adaptive crash structure is a structure of a vehicle that can be adapted in the event of an accident or a predicted accident, so that the crash characteristics of the vehicle change. The crash characteristics change in such a way that a vehicle occupant is better protected from the accident. The vehicle may be a car or a commercial vehicle or another suitable vehicle.

The strut is a component that can be used in the adaptive crash structure. This strut has an arbitrary cross-section, it may for example have a circular, an ellipsoid, a rectangular, a prismatic, a triangular or any other suitable cross-section. The strut has the outer wall which encloses the cavity. For example, the cavity may be continuous. In this case, the strut is formed in the manner of a tube. Alternatively, the strut may have a non-continuous cavity, the z. B. of intermediate walls of the outer wall is limited. In this case, the strut is formed, for example, in the manner of a bamboo tube. The strut is either straight or has one or more bends or angles.

Within the cavity of the strut powdery material is arranged, which at least partially fills the cavity. The powdery material may, for. Example, a thermoplastic (for example, polypropylene PP, polystyrene PS, polyamide PA, or the like), a thermoplastic compound with a filler to increase the strength, to improve the thermal properties, the shrinkage behavior or the processability, a metallic material (for example aluminum, Steel, magnesium, titanium, copper, tin, and alloys of these metals, or the like), or a ceramic material.

The at least two electrodes protrude into the cavity of the strut. The electrodes contact the powdery material. The electrodes are spaced apart from each other and face each other. Each electrode may be connected to a power source when the strut is used in an adaptive crash structure of a vehicle. Of course, each electrode can be connected to the same power source. Alternatively, each electrode can be connected to a separate power source. If the at least two electrodes are connected to a current source, a current flow can take place between the two electrodes.

The current thus flows through the powdery material, which is located in the cavity of the strut. Due to the flow of current, the powdery material is heated, melted and solidified. By remaining in this material residual heat results in a ductile-ductile material behavior, whereby a higher energy absorption is possible than with the unconsolidated powdery material. This makes it possible in the event of an accident, to activate the adaptive crash structure of the vehicle and to increase the protection of the vehicle occupants.

In one embodiment, each electrode has an insulator, the insulators isolating the electrodes toward the outer wall of the strut. By the insulators, the flow of current through the powdery material is favored.

According to a further embodiment, the strut has two ends and the at least two electrodes face each other at the two ends of the strut. If the strut is formed in the manner of a tube, an electrode is arranged at each end of the tube. If the strut has intermediate walls, electrodes can additionally be arranged on the intermediate walls.

According to a further embodiment, the outer wall of the strut and the powdery material are formed of the same material. For example, both the outer wall and the powdery material may be formed from a thermoplastic, from a thermoplastic compound, from a metallic material or from ceramic. The material is thus present in a solidified and in an unconsolidated state.

According to a further embodiment, outer wall of the strut is produced by means of an additive manufacturing process. In this case, the powdery material z. As a thermoplastic, a thermoplastic compound, a metallic material, a ceramic material may be solidified only at the points that are to form the outer wall. The enclosed by the outer wall powdery material thus remains within the outer wall. This makes it possible to produce the strut in a simple and fast way. The step of filling the cavity with the powdery material is eliminated during the manufacturing process of the strut.

An additive manufacturing process is, for example, a sintering process, for. B Selective Laser Sintering (SLS), Selective Laser Melting (SLM), or laser deposition (evaporation) possible. Additive manufacturing is also referred to as 3D printing.

According to a further embodiment, the outer wall is formed from a thermoplastic or from a thermoplastic compound. For example, the outer wall may be formed of PP, PS or PA. For example, the outer wall may be formed from a thermoplastic compound. This thermoplastic compound has fillers such as lime, fiber or chemical additives. This serves to improve the strength, the thermal properties, the shrinkage behavior or the processability. The powdery material, which is arranged within the cavity, can be made of the same material as the outer wall. Alternatively, the powdery material disposed within the cavity may be formed of a material different from the material of the outer wall.

Alternatively, the outer wall is formed of a ceramic. The powdery material, which is arranged within the cavity, can be made of the same material as the outer wall. Alternatively, the powdery material disposed within the cavity may be formed of a material different from the material of the outer wall.

Again alternatively, the outer wall is formed of a metal. In this case, iron metals and non-ferrous metals can be used. For example, steels of all current and available alloys, or light metals such as aluminum, magnesium or titanium, or non-ferrous heavy metals such as copper or tin, as well as possible alloys of these metals can be used. The powdery material, which is arranged within the cavity, can be made of the same material as the outer wall. Alternatively, the powdery material disposed within the cavity may be formed of a material different from the material of the outer wall.

The adaptive crash structure for a vehicle has at least one strut which has already been described in the previous description. This adaptive crash structure may, for example, be in the form of an open or closed profile. Furthermore, this adaptive crash structure can be designed, for example, as a prismatic, conical or curved profile. The cross section of this profile is freely selectable. The strut is operatively connected to the profile. This means that forces from the profile can be introduced into the strut or from the profile into the strut. Of course, the adaptive crash structure may have more than one strut. If the adaptive crash structure has more than one strut, these struts may be either uniform or formed differently from each other.

For example, the adaptive crash structure may be used in a vehicle as a body component. For example, the adaptive crash structure as a body side member, crash cone, side skirts, door strut, or similar. be used. Furthermore, the adaptive crash structure as a chassis component, z. B. as trailing arm, control arm or similar, find use. In a frontal collision or a side impact of a vehicle both bodywork and chassis components are affected. Therefore, an adaptive crash structure may be provided both as a body component and as a chassis component in order to increase the safety for the vehicle occupants in such a case. In so-called impact load cases, z. B. when skidding the vehicle against curb, the chassis is mainly affected. Therefore, the adaptive crash structure can be provided as a chassis component in order to increase the safety for the vehicle occupants in such a case.

The vehicle has at least one adaptive crash structure which has already been described in the previous description. In addition, the vehicle has at least one triggering device. The electrodes of each strut are connected to a power source, and each strut is connected to the at least one tripping device, by means of which the current flow between these electrodes is triggered. The trigger device controls the current source or the current sources, so that a current flow between the electrodes is triggered and then terminated again. In other words, the triggering device activates the current source or the current sources and then deactivates them again. The triggering device may be, for example, a control unit. The triggering device is connected via the power source or via the power sources to the electrodes of the at least one strut.

As a power source, for example, one or more capacitors (SuperCap) or a high-voltage system of an electric drive train or hybrid powertrain, which is discharged suddenly similar to a short circuit.

In the event of an accident, the tripping device triggers the current source or sources so that current flow is initiated between the electrodes of the at least one strut of the adaptive crash structure. Because of the current flow, the powdery material is heated, melted and solidified. By remaining in this material residual heat results in a ductile-ductile material behavior. Thus, the adaptive crash structure is activated. The triggering device then stops the current flow. The activated adaptive crash structure may, in the event of an accident, e.g. B. in the event of an impact, take a larger amount of energy than would be possible for an inactive adaptive crash structure or a conventional chassis or body component. This increases the safety of the vehicle occupants in the event of an accident.

According to another embodiment, the vehicle has an accident prediction system connected to each triggering device. At least one of the tripping devices triggers a current flow between the electrodes of the at least one strut in the event of a predicted accident.

The commercially available system for accident prediction can determine when an accident, for. B. an impact is unavoidable. The system for accident prediction determines accident data to z. B. a crash partner, an impact angle, a relative speed, an impact point, a direction from which the crash partner moves toward the vehicle or in which the vehicle moves towards the crash partner o. Ä.

If the accident prediction system determines that an accident is unavoidable, the accident prediction accident data will be forwarded to each trip device. Depending on the impact point, impact angle and relative speed, those struts of the at least one adaptive crash structure are activated, which will be affected by the predicted accident. This means that at least one of the tripping devices activates the flow of current in this or these struts, so that solidification of the powdered material can take place. The at least one adaptive crash structure is therefore already before the actual accident, z. B. activated before the impact. As a result, that area of the vehicle that is affected by the accident can be reinforced. Thus, more energy can be absorbed by the body and / or the chassis in this area. This increases the safety for the vehicle occupants.

In a method for adapting at least one adaptive crash structure of the vehicle, which has already been described in the previous description, the accident prediction system determines an unavoidable accident and forwards a signal to the at least one triggering device of the vehicle. This signal may contain, for example accident data to z. B. a crash partner, an impact angle, a relative speed, an impact point, a direction from which the crash partner moves toward the vehicle or in which the vehicle moves towards the crash partner o. Ä.

This tripping device triggers a current flow between the electrodes of at least one strut of the at least one adaptive crash structure. It is targeted a current flow between the electrodes of the at least one strut is triggered, which will be affected by the accident.

Then the powdery material solidifies in the cavity of the at least one strut. This happens due to the generated heat. This results in a viscous-ductile material behavior within the cavity of this strut. This allows a higher energy consumption by this strut.

According to one embodiment, based on the predicted accident data of the system for accident prediction, the pulverulent material of the at least one strut of that adaptive crash structure of the vehicle is solidified, which is arranged in the region of a power transmission during the accident. In other words, a solidification of the powdered material takes place only in those areas of the vehicle that will be affected by the accident.

In a method for producing a strut which has already been described in the previous description, the outer wall of the strut is produced by means of the additive manufacturing method already described. In the cavity of the strut remains the powdery material and is not fused or sintered during the manufacturing process.

• 1 eine schematische Schnitt-Darstellung einer adaptiven Crash-Struktur nach einem Ausführungsbeispiel,
• 2 eine schematische Darstellung eines Verfahrens zur Adaption der adaptiven Crash-Struktur aus 1.

Various embodiments and details of the invention will be described in more detail with reference to the figures explained below. Show it:

• 1 1 is a schematic sectional view of an adaptive crash structure according to an exemplary embodiment,
• 2 a schematic representation of a method for adapting the adaptive crash structure 1 ,

1 shows a schematic sectional view of an adaptive crash structure 2 according to an embodiment. Shown is the adaptive crash structure 2 which is a body part of a vehicle. The adaptive crash structure 2 is a trapezoidal, open profile P educated. The adaptive crash structure 2 has a strut 1 and two ribs R on. Ribs R and the strut 1 are active with the profile P , Interconnected means that a connection between the profile P and the strut 1 or the ribs R exists, allowing forces directly from the profile P in the strut 1 or in the ribs R can be transmitted or vice versa.

The strut 1 has an outer wall 3 on that a cavity 4 includes. The strut 1 is tubular. Inside the cavity 4 is powdery material 7 arranged. The outer wall 3 and the powdery material 7 are made of the same material. The strut 1 is manufactured by means of an additive manufacturing process.

The strut 1 has two electrodes 5 on. Each electrode 5 is by means of an insulator 9 from the outside wall 3 isolated. The electrodes 5 are at the ends 10 the strut 1 arranged. A first electrode 5 is at a first end 10 the strut 1 arranged. A second electrode 5 is at a second end 10 the strut 1 arranged. The electrodes 5 lie opposite each other. The electrodes 5 protrude into the powdery material 7 into it. Each electrode 5 has a connection 12 for a power source. Both are electrodes 5 connected to the same power source. Will a current flow between the two electrodes 5 generates, the powdery material 7 heated, melted and solidified. This results within the outer wall 3 a ductile-ductile material behavior, whereby a higher energy absorption is possible than with the unconsolidated powdery material 7 ,

2 shows a schematic representation of a method V for adaptation of the adaptive crash structure 2 out 1 in a vehicle. The vehicle has the adaptive crash structure 2 , a system for accident prediction 13 , a triggering device 11 , and a power source 6 on. The triggering device 11 is with the power source 6 connected. The power source 6 is with the electrodes 5 the strut 1 the adaptive crash structure 2 connected. The triggering device 11 is also with the system for accident prediction 13 connected.

The system for accident prediction 13 notes that an unavoidable accident is imminent. In addition, the system determines the accident prediction 13 Accident data regarding z. B. an impact point, an impact angle, a relative speed. The system for accident prediction 13 transmits a signal S to the triggering device 11 , This signal S may, for example, contain the accident data.

The triggering device 11 then controls the power source 6 by means of a control signal 14 on. The power source 6 is activated. The power source 6 releases a current flow 8th between the electrodes 5 the strut 1 out. The stream flows through the powdery material 7 which is heated thereby. Due to the heating, the powdery material 7 melted. When the current flow 8th is interrupted, there is a solidification 15 of the molten powdery material 7 , The result is the tough-ductile material behavior 16 inside the outer wall 3 the strut 1 ,

The examples described here are only examples. For example, the adaptive crash structure may have a different shaped profile respectively. The adaptive crash structure may have more than one strut.

LIST OF REFERENCE NUMBERS

1

strut

2

adaptive crash structure

3

outer wall

4

cavity

5

electrode

6

power source

7

powdered material

8th

current flow

9

insulator

10

The End

11

triggering device

12

Connection for the power source

13

System for accident prediction

14

control signal

15

consolidation

16

tough-ductile material behavior

R

rib

P

profile

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 201410001865 B3 [0003]
• DE 201310204896 A1 [0004]

Claims (13)

Strut (1) for an adaptive crash structure (2) of a vehicle, the strut (1) having an outer wall (3) enclosing a cavity (4), characterized in that the strut (1) comprises at least two electrodes (2). 5) which protrude into the cavity (4) with the electrodes (5) facing each other and each electrode (5) being connectable to a power source (6), and that the strut (1) comprises a powdered material (7) , which is arranged within the cavity (4), wherein the powdery material (7) by means of a current flow (8) between the two electrodes (5) solidifiable (15). Strut (1) to Claim 1 , characterized in that each electrode (5) comprises an insulator (9), the insulators (9) insulating the electrodes (5) towards the outer wall (3) of the strut (1). Strut (1) according to one of the preceding claims, characterized in that the strut (1) has two ends (10), and the at least two electrodes (5) at the two ends (10) of the strut (1) are opposite. Strut (1) according to one of the preceding claims, characterized in that the outer wall (3) of the strut and the powdery material (7) are formed of the same material. Strut (1) according to one of the preceding claims, characterized in that the outer wall (3) of the strut (1) is produced by means of an additive manufacturing process. Strut (1) according to one of the preceding claims, characterized in that the outer wall (3) is formed from a thermoplastic or from a thermoplastic compound or from a ceramic or from a metal. Adaptive crash structure (2) for a vehicle, characterized in that it comprises at least one strut (1) according to one of the preceding claims. Adaptive crash structure (2) after Claim 7 , characterized in that it is a body component or a chassis component of the vehicle. Vehicle, characterized in that the vehicle at least one adaptive crash structure (2) according to one of Claims 7 to 8th and at least one triggering device (11), wherein the electrodes (5) of each strut (1) are connected to a current source (6), and wherein each strut (1) is connected to the at least one triggering device (11), by means of which Current flow (8) between these electrodes (5) is triggered. Vehicle after Claim 9 , characterized in that the vehicle has a system for accident prediction (13), which is connected to each triggering device (11), wherein at least one triggering device (11) in the event of a predicted accident, a current flow (8) between the electrodes (5 ) which triggers at least one strut. Method (V) for adapting at least one adaptive crash structure (2) of a vehicle to one of Claims 9 or 10 , characterized in that - the system for accident prediction (13) detects an unavoidable accident and forwards a signal (S) to the at least one triggering device (11) of the vehicle, - this triggering device (11) a current flow (8) between the Electrodes (5) of at least one strut (1) of the at least one adaptive crash structure (2) triggers, - the powdery material (7) solidifies in the cavity (4) of the at least one strut (1), - inside the cavity ( 4) of this strut (1) results in a ductile-ductile material behavior. Method (V) according to Claim 11 , characterized in that, starting from the predicted accident data of the system for accident prediction (13), the pulverulent material (7) of the at least one strut (1) of that adaptive crash structure (2) of the vehicle is solidified in the region of a power transmission is arranged during the accident. Method for producing a strut (1) according to one of the Claims 1 to 6 , characterized in that the outer wall (3) of the strut (1) is manufactured by means of an additive manufacturing process, wherein in the cavity (4) of the strut (1) the powdery material (7) remains and is not fused or sintered during the manufacturing process.

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