The present invention relates to structural elements with variable deformation property
and structures based on it.
Out DE 197 41 766 A1
is a foamed structure known for a vehicle. By introducing a gaseous, liquid or powdery medium into the foamed structure, its physical properties can be changed. As a result, it is possible, for example, to change the rigidity of a foam structure acting as an energy absorption element in a vehicle in accordance with the collision conditions. The thermal or acoustic properties of foamed surface elements can also be influenced. The force-displacement characteristic of the foamed structure can be changed according to the collision conditions (collision velocity, impact direction, collision object, etc.), so that ideally the stiffness and the energy absorption capacity can be adapted to the respective collision conditions. If, for example, the vehicle according to the invention is a vehicle with a high dead weight, a force-displacement characteristic with a correspondingly flat profile can be set by the invention in the event of a collision with a lighter vehicle (compatibility). Even in collisions with pedestrians or cyclists, a significant reduction in the stiffness of the energy absorbing element can reduce the impact on the weaker casualty. If, on the other hand, the vehicle hits against a stationary obstacle, the rigidity is correspondingly increased in the sense of maximum self-protection. Thus, an adjustable crush zone characteristic can be generated. The charging or discharging of the foamed structure is initiated by a so-called "pre-crash sensor" before or in the initial phase of a collision.
The foamed structure out DE 197 41 766 A1
has the disadvantage that it is relatively expensive to produce. In addition, it needs for adaptation external pumps to enter the medium in the foamed structure or let out. These pumps or similar must be powerful and therefore expensive to suitably adjust the foamed structure within the short time available between crash pre-detection and impact. The right attitude based on the pre-crash data also requires a considerable amount of computation during adjustments. In addition, this structure in their properties, eg. As the force-displacement curve, only preset, which leads to an adaptive behavior, but the force-displacement curve is similar to a 'bulk material' characteristic without qualitative change in behavior during deformation.
is therefore the object of the present invention, a possibility
to provide for the design of vehicle structures, which
flexible, very easy and inexpensive to vehicle designs
can be adjusted and which increased security regarding self protection of
Driver as well as partner protection, as well as pedestrians can provide.
The object is achieved by a structural element according to claim 1, a longitudinal structure
according to claim 21, a vehicle according to claim 22 and a set of
Vehicles according to claim 23 solved. advantageous
Embodiments are in particular the dependent claims individually or in combination
The structure element is set up and adapted for response
upon reaching at least one threshold value of a control parameter
between two different deformation load levels of the structural element
switch. In other words, in response to the achievement
at least one threshold value of a control parameter between two
switched different stiffnesses of the structural element for a deformation
Switching happens - in
Frame of inertia
and reaction forces
of the structural element - in particular
d. h., that an associated or
Force Deformationsweg line a substantially stepped waste
shows. In other words changes
the load level of the structural element or its stiffness value
So if an inner and / or outer load path
or rigidities change,
by depending on the constructive solution
the stiffness is fast or the system no inertia
has a correspondingly rapid decrease or increase in the
Total load levels. In practice, typically a few milliseconds
until reaching a new load level. In a crash
Depending on the load, typically between 60 and 150 ms are required until
the car is standing.
the deformation property leaves
the structural element flexible to different deformation scenarios
to adjust. Particularly attractive is the also resulting adaptability
to vehicles of different product lines and municipal vehicle structures,
although the structural element then may need to be adjusted,
but does not need to be redesigned.
The control parameter can be the deformation path of the structure element, the associated threshold value can then be, for example, a predetermined length on the deformation path of the structure turelements, so that depending on the deformation path, the load level is changed. In this case, the structural element can thus switch automatically.
Another control parameter can be a pressure threshold value of a liquid
be in a chamber of the structural element.
Control parameters can
but also be external parameters by a vehicle sensor
be delivered, such as an impact velocity,
an obstacle size or
an obstacle type, an impact type, an impact angle, a time
after impact and so on. This is particularly advantageous
when using data of a so-called 'pre-crash' environment sensor, z. By radar,
because then the sensor data already before or at the beginning of an impact
can be used to
to adapt the deformation structure to the type of impact, thereby
a particularly flexible and effective impact protection is possible.
also different thresholds, possibly to different control parameters
switch different load levels, especially one after the other.
Load levels and / or the threshold or thresholds may be structural
adjustable, but then be firm and / or individually during an impact
is particularly advantageous when the structural element is set up
and adapted to, at the beginning of a deformation, a first load level
show and with progressive deformation after reaching
a threshold value associated with the deformation state (eg deformation length, pressure
etc.) to switch to a second load level.
but can also be advantageous if the structural element set up
and adapted to it, before the beginning of a deformation on the basis
an external control parameter (eg impact velocity,
Obstacle size, impact type, impact angle,
Time after impact beginning, etc.) from a first load level
to switch a second load level. This makes it special
Impact reaction of a vehicle (in particular imaged by
its rigidity) between a pedestrian impact and a vehicle crash,
and there again between a low velocity impact
and to differentiate a high-speed impact.
For a pedestrian safety
a very low rigidity is desired, but for self-protection
a higher one
of the entire impact. An ideal impact pulse also has one
Stiffness drop on impact for self-protection and a
reduced occupant burdens.
the load levels are associated
adjustable according to different stiffness levels.
the structural element has an outer structural part
and an inner chamber disposed therein with at least one therein
contained chamber element, wherein the outer structural part has an outer load path
forms and the chamber element initially
forms an inner load path, and wherein the outer load path and the inner load path
define the first load level, and the second, following
Load level due to a weakening
the inner load path is defined. After reaching the predetermined
Threshold of the structural element thus causes the inner structural part
a drop in rigidity of the structural element. In other
In words, an inner load path 'collapses'
at least down to a certain level, so that on the structural element
acting force is now substantially absorbed by the outer structural part
must be ('outer load path'), which makes this
Deformation and thus energy absorption deformed.
is advantageous if the inner chamber element is a liquid
is whereby switching between two load levels thereby
that the liquid
can not leave the inner chamber at the first load level (z.
B. because an opening through
a diaphragm and / or a valve is blocked), whereby by the
or the pressure in the liquid speed
the inner load path is built, and that after reaching the
Threshold the liquid
leave the inner chamber (eg by rupture of the membrane
the valve), which defines the second, lower load level,
the inner load path is reduced by the pressure drop or completely
will be annulled.
can be particularly cheap
be when the inner chamber has an opening by means of
a closure element, in particular a membrane, sealed
which is after reaching a pressure threshold of the liquid
It is particularly favorable if the height of the second load level is determined by a flow cross-section of a valve which determines the size of the opening of the inner chamber. As a result, for example, even before the impact, the second, possibly very early onset, load level for pedestrian safety can be set to a low value or occupant safety to a higher level. The switching can, as be already discussed above are determined by external sensor readings.
can be cost effective
Production but also be advantageous if the valve is a mechanical
driven valve is after reaching a predetermined
Deformationswegs is switched.
is in particular for adjusting the structural element in front of a
Impact beneficial when the valve is an electrically controllable
Valve is by means of an external control signal between at least
two flow cross sections
can also be cheap
be when the height of the
second load levels through a flow cross section of a puncture
a boundary diaphragm of the inner chamber is determined according to
Achieving a predetermined deformation path by means of a
generated in the chamber piercing element is generated. This
results in a particularly cost-effective
and robust implementation.
but may also be advantageous if the liquid is a rheological
is, its viscosity
by means of an associated
Field generating device is adjustable, so that at least one of
Load levels can be adjusted by adjusting the viscosity. Then can
z. B. often
to dispense with a valve for adjusting the pressure drop. It
is then particularly favorable,
if the viscosity of the
by means of an associated
Field generating device is adjustable, so that the switching
between load levels through a change
but also desired
be that the chamber element at least one attached to the outer structural part
Structural element is that by deformation the second load path
of the first load level, the switching to the second load level
at least one connection with the outer structural part happens.
the release happens
of the chamber element by ignition
a pyrotechnic connecting element. Advantage here is the
simple constructive solution
with already existing components. This arrangement is also
an impact by opening
the lock switchable, resulting in improved self-protection and
improved occupant protection results. This version is also suitable
for impact speed controlled
whereby a preconditioned system can be created.
Structural element can also be at least two areas different
Having stiffness, each defining one of the load levels.
The different stiffness can be Z. B. by different
the äuße ren structural part
to reach. The control parameter can then z. B. the Deformationsweg
and the threshold corresponds to the position on the deformation path
of the transition
between the two areas.
may also be advantageous if the structural element an outer structural part
and an inner chamber disposed therein with at least one therein
comprising deflecting element, wherein the outer structural part has a load path
forms the first load level by means of a fold-fold deformation,
and wherein after reaching a predetermined deformation path, the deflecting element
so in the outer structural part
deflects that outer structural part
a load path on the second, lower load level through transition
forms a bending deformation.
All in all
For example, the invention may be arranged between more than two
Switch load levels and / or be set up between
two load levels based on several independent thresholds
is also cheap
if the structural element at least a part of a motor carrier, a chassis carrier or
a Defoelements is. Defo elements typically represent the
Connection between bumper cross member and
The following is the invention with reference to embodiments schematically
described in more detail.
1 shows an oblique view of typical, known components of a vehicle structure.
2 schematically shows a sectional side view of a motor carrier according to the invention;
3 shows one to the engine mount 2 corresponding basic application of the engine mount 2 absorbed force or load in any units against the deformation in any units;
4 schematically shows a sectional side view of another embodiment of a motor support according to the invention;
5 schematically shows a sectional side view of another embodiment of a motor support according to the invention;
6 shows one to the engine mount 5 corresponding basic application of the engine mount 5 absorbed force or load in any units against the deformation in any units;
7 schematically shows a sectional side view of yet another embodiment of a motor support according to the invention;
8th schematically shows a sectional side view of another embodiment of a motor support according to the invention;
9 shows one to the engine mount 8th corresponding basic application of the engine mount 8th absorbed force or load in any units against the deformation in any units;
10 schematically shows a sectional side view of yet another embodiment of a motor support according to the invention;
11 shows one to the engine mount 10 corresponding basic application of the engine mount 10 recorded force or load in any units against the Deformationsweg in any units;
12 schematically shows a sectional side view of another embodiment of a motor support according to the invention;
13 schematically shows a sectional side view of yet another embodiment of a motor support according to the invention;
14 shows one to the engine mount 13 corresponding basic application of the engine mount 13 absorbed force or load in any units against the deformation in any units;
1 shows in an oblique view typical components of a partially drawn vehicle structure and typical load entries in a frontal impact.
A front impact is typically a load entry on one
occur as indicated by A and the associated arrow. Further
a load entry on a support beam, B, and
a wheel, C, occur. Other components include, for example
a support bracket of a wheel housing D,
E, a sill reinforcement
K, a support G of a
Front wall, a tunnel strike plate
H, a heel plate I and a rear engine mount J.
Construction is a voting compromise of stiffness and load levels for those too
Requirements in the load cases
or impact cases
necessary. This is depending on the impact situation a previous structure
at low impact speed too hard and for optimal absorption
the energy at high speed too soft. Occupant protection systems
(Beltsystem, airbag, etc.) are for minimizing the occupant loads
to tune these non-optimal structural properties so that
Even the overall system so far can not show optimal performance.
2 shows a motor carrier 1 , which directly - at position x 2 to a passenger compartment 2 is articulated. The engine mount 1 is through a panel 3 at position x 1 in a front chamber 4 and a rear chamber 5 divided. The aperture 3 has an opening 6 for connection between front chamber 4 and a back chamber 5 , To seal the opening 6 is this with a membrane 7 Mistake. Additionally located in the opening 6 a controllable valve 8th , The front chamber 4 is with a fluid, here: a liquid 9 filled.
In a front impact shown here causes one on the front end 10 of the engine mount 1 force exerted at x 0 is a fold-buckling deformation of the engine mount 1 More precisely, a deformation of the liquid-filled front chamber 4 , The internal pressure generated by the deformation in the anterior chamber 5 opens the membrane after exceeding a presettable pressure threshold 7 (eg, these are tearing), and the fluid 9 flows through the valve 8th in the rear chamber 7 , and from there, if necessary, through another opening 11 outward. In this embodiment, the valve 8th be switched between two different flow cross sections. For better clarity, associated signal and power lines, as well as a control device used for control are not shown.
3 shows one to the structure of 2 appropriate representation of a deformation behavior.
The total load level Fv, that of the front part of the engine mount 1 out 2 is taken from the load level Fvm of the front chamber 5 comprehensive part of the engine mount with the load level Ff1 through the fluid 7 with closed front chamber 4 together. In other words, the entire load path of the front part of the engine mount from x0 to x1 is from an outer load path through the structure of the engine mount 1 itself and an internal load path through the fluid-filled volume and is Fv = Fvm + Ff1.
In a collision with a sufficiently high force F on the front face 10 becomes next to the front part of the engine mount 1 as long as the load level Fv = Fvm + Ff1 deformed until the pressure of the fluid 9 through the compression of the anterior chamber 5 rises to a threshold at which the membrane 7 opens. This allows the fluid 9 from the front chamber 5 under pressure drop in the rear chamber 6 stream. The flow velocity and thus the pressure drop is due to the flow cross-section of the valve 8th adjustable in a first position. Due to the usually high deformation rate, the liquid remains 9 pressure and thus can continue to serve as a load path, but at a lower level Ff0, so that the engine mount now has a total load level Fv = Fvm + Ff0 <Fv = Fvm + Ff1.
Will be the valve in the following 8th so controlled that the flow cross-section further increases in a second position, the pressure of the liquid decreases 9 so far off that the fluid 9 is no longer suitable for receiving loads, so that the front part only a maximum load level of the actual engine mount 1 or the engine mount shell in this area of Fvm. In other words, the inner load path is eliminated. This means that the stiffness of the front part suddenly drops further and makes it easier to deform.
This deformation continues until the deformation covers the rear part of the engine mount from x1 to x2. Since the rear part is stiffer, the load level increases again to a maximum of Fhm. Will the engine mount 1 even further to the passenger cabin 2 (or another part of the vehicle structure) compressed, the deformation is mainly determined by their, usually much higher, rigidity.
The height Ff1, Ff2 of the internal fluid load paths in the front chamber 4 can be adjusted, for example, by changing the cross-sectional area and the volume of the front chamber 5 , by the type of fluid 7 (For example, more viscous or less viscous), through the flow cross-sections of the valve 8th , by the switching characteristic of the valve 8th , by the pressure threshold for opening the membrane 7 set etc.
By in the 2 and 3 As described, a structure which is particularly adaptable to various types of impact and impact levels is produced.
With a comparatively small force F, corresponding typically to a collision at low speed, at which the opening threshold value of the membrane 7 is not exceeded, the engine mount remains 1 comparatively stiff, so that a vehicle equipped with it is not significantly distorted.
With a comparatively large force F, corresponding typically to a collision at high speed, the motor support initially remains relatively stiff, but then leaves after opening the opening 6 easier to deform under absorption and dissipation of a considerable amount of impact energy. It thus forms an effective crumple zone. This happens until the deformation of the passenger compartment 2 approaching, which should deform little to occupant protection. Before the deformation of the passenger compartment 2 achieved, the deformation ability (increases the rigidity) decreases at the rear of the engine mount 1 again, to the passenger compartment 2 to protect itself from deformation.
In the illustrated arrangement gives the possibility of a stiffness of the engine mount 1 Almost immediately change significantly, a previously unknown flexibility in the crash design of vehicle structural parts.
Furthermore, results from the use of the electrically controlled valve 8th the hitherto unknown possibility, the opening of the valve 4 in response to any sensors mounted on the vehicle, such as pressure sensors in the front chamber 4 or strain and / or velocity sensors outside the engine mount 1 , which further increases the flexibility of this crash structure.
Furthermore, there is now the possibility of being able to use a structural element according to the invention, if necessary with only minor structural adjustments, for different production lines by adapting the opening property of the valve 4 .. This is particularly advantageous for vehicles of different variants within a vehicle class or production lines. In these, the basic structure is the same, but previously had to be comparatively complicated adjustments to take into account a higher weight, a higher speed, etc. are performed so that, for example, a mandatory occupant safety was guaranteed. With the above invention now only needs the valve 4 to be adapted, if necessary electronically.
In another method for operating the engine mount 1 (or eg a Defo box) becomes an electrically controlled valve 8th used. The valve 8th is set between different flow cross sections before an impact. The decision as to which flow cross-section is active is made in particular on the basis of the type of impact (eg with a pedestrian or a heavy obstacle), the impact speed (eg less than 20 km / h or greater than 20 km / h) and /or other parameters.
For example, if an (upcoming) impact with a pedestrian is detected by an external control system, the valve becomes 8th switched to a large passage to reduce stiffness and make the impact 'softer'. The membrane may in this embodiment (and, as the case may be, in other embodiments as well) merely hold the liquid 9 be used in the undeformed state, so that it breaks already at a very low internal pressure and the inner load path of the closed chamber 4 contributes little to the deformation property.
However, if the on-board sensors detect a collision with a heavier obstacle (vehicle, wall, etc.), the valve becomes 8th switched to a small passage, so as not to reduce the rigidity that the passenger compartment 2 can be damaged. The impact is' made harder.
In yet another embodiment, for example, a valve 8th be dispensed, whereby after opening the membrane 7 the load level Fv immediately drops from Fv = Fvm + Ff1 to Fv = Fvm. Flexibility is lost, but this embodiment is easier and less expensive.
the invention is not limited to the use of only one valve or
on only two open positions
of the valve. So z. B. also a valve with gradually variable
be used, giving an even finer control
In a further embodiment (not shown) is absent compared to that of 2 also the valve, however, the liquid is a rheological fluid, and the front chamber accommodating it is provided with appropriate means for establishing an electric and / or magnetic field through the rheological fluid. By setting the appropriate field strengths, the viscosity of the rheological fluid can be adjusted within a wide range. As a result, in particular after exceeding the threshold pressure necessary for opening the membrane, the flow velocity of the rheological fluid from the front chamber can be adjusted, and thus also the height of the remaining inner load path. This corresponds in effect to the presence of a valve, in particular a continuously variable valve. The valve can be switched for example by means of hydraulic cylinders (not shown). Depending on the design and materials used, it is also possible to dispense with the membrane.
where like, like that
already discussed above, the viscosity of the rheological fluid
already before a collision z. B. on the nature and strength of
Impact is adjusted.
Adjusting the system before impact is appropriate to all
external circuit applicable ..
4 shows a further embodiment of a motor carrier 12 , in the fundamental deformation or load behavior of the in the 2 and 3 similar embodiment shown.
In this embodiment, an increase in the flow cross-section is now achieved not by a circuit of a valve, but in that the diaphragm by means of a piercing element 11 at the front end wall 10 the front chamber 4 is attached, is broken, as indicated schematically by the curved arrows. If the engine carrier 12 that is pushed together by a certain deformation path, pushes the puncture element 13 on the (typically already through the destroyed membrane 7 open) aperture 3 and presses it so that the flow cross-section becomes larger. Due to the resulting enlarged Publ tion the liquid occurs 7 faster, especially after the head of the piercing element 13 the aperture 3 has passed through and only the narrow shaft in the opening 6 remains.
The shape of the piercing element 13 is not limited to the form shown, but may have all the skilled person known forms, for. B. with a chamber wall 10 directed tip.
This basically results in the already in 3 behaviors shown.
5 shows a further embodiment of a motor carrier according to the invention 14 that compared to here 1 without further internal division with its entire interior a chamber 15 for receiving the liquid 9 forms. The chamber 10 has a valve 16 for selectively switching the flow cross section through the valve 16 on the opening leading to the outside 11 on. The opening 11 is through a membrane 7 sealed. This is the mode of action of the opening ( 11 )-/Valve( 16 ) - / membrane system similar to the analog system 2 ,
The advantage of the continuous chamber 15 opposite the compartmentalized chamber 2 is that the carrier 14 is simpler and thus cheaper to produce.
In a further embodiment (not shown) similar to 5 is missing in this regard, the valve, but here too, the liquid may be a rheological fluid, and the chamber 15 is equipped with appropriate means for establishing an electrical and / or magnetic field through the rheological fluid. By adjusting the corresponding electric or magnetic field strengths, the viscosity of the rheological fluid can be adjusted within a wide range. As a result, in particular after exceeding the threshold pressure necessary for opening the membrane, the flow velocity of the rheological fluid from the front chamber can be adjusted, and thus also the height of the remaining inner load path. This corresponds in effect to the presence of a valve, in particular a continuously variable valve. Depending on the design and materials used, the membrane can also be dispensed with here.
The deformation or load-bearing behavior of the crash structure 5 (and their described modifications) is in 6 shown in more detail, to which reference is now made. The engine mount 15 out 5 deforms similarly to the one in 3 behavior except that now the increase of the load level on fhm off 3 does not occur, the engine mount 15 or its shell has an equal rigidity over the deformation range x0 to x2. In the embodiment according to 5 thus increases only after reaching the passenger compartment 2 the stiffness again considerably. Thus, also for in the 5 and 6 illustrated engine mount 9 Achieves the desired "high-low-high" deformation or stiffness profile, with a (sufficiently strong) force application
- - First, a comparatively high rigidity is present, in which, in another view, an inner and an outer load path to absorb the applied load, corresponding to a load level of, Fv (= Fvm + Ff1);
- - after opening the membrane 7 and small cross-sectional opening of the valve 16 a pressure drop in the chamber 15 the stiffness there drops to a lower load level Ff0, so that the load level of the entire engine mount 14 falls to a load level Fv = Fvm + Ff0 <Fvm + Ff1;
- - after switching the valve 16 on the larger flow area, the pressure drop in the chamber 15 the stiffness abruptly, corresponding to the elimination of the internal load deposit by the fluid 7 , the load level drops to Fvm; and
- - When reaching the passenger compartment 2 the stiffness increases again or the load level increases to F (passenger compartment).
As with the ones to 2 and 3 In this case too, the valve structure can be dispensed with, which results in a drop in the load level from Fv = Fvm + Ff1 to Fv = Fvm. Also, the deformation behavior is similar for the rheological fluids.
Compared to the embodiments of the 2 and 3 Although a level in the load level is missing here, which makes the crash behavior less flexible, but makes the crash structure easier and cheaper.
The reason for the missing level, however, is not the fact that in the 2 and 3 the interior of the crash structure is subdivided while in 4 a single chamber is used, but that in the 2 and 3 the engine mount in the rear part or its shell (ie the outer load path) structurally has a higher load level than the shell in the front part (also corresponding to the outer load path). This can be z. B. by a higher wall thickness, etc. in the rear part (from X1 to x2) can be achieved. In further variations of the embodiment, the rear part of the engine mount may be formed, for example, without higher rigidity.
Analog can be characterized by structural stiffening of sections of the actual engine mount 5 one, possibly multiple gradation can be achieved.
7 shows a further embodiment of a complete with a liquid 9 filled engine mount 17 in which, in contrast to the embodiment of 5 the valve is not controlled electronically, but a mechanical valve in the form of a sliding aperture 18 with two adjacent openings 19 . 20 with different diameter. The force F causes a fold-buckling deformation of the engine mount 17 , The internal pressure opens the membrane (without reference numeral) from a certain internal pressure, and the fluid 9 then flows through the opening 18 and through the smaller aperture 19 outward. If the deformation is the connection of the aperture 18 has reached, this is pushed in the direction of deformation and gives the larger opening 20 free, which further reduces the internal forces in the fluid load path. The deformation behavior can in turn by 6 basically described.
8th shows a further embodiment of the structural element according to the invention in the form of a motor carrier 21 , with a deformation similar to that of 3 is very similar. However, in contrast to, in particular, too 2 the inner load path is not formed by a liquid, but by a mechanical structure consisting of two at the front 10 of the engine mount 21 hinged longitudinal struts 22 which exists on their ande ren side with inner side walls of the engine mount 21 by means of a pyrotechnically switchable element 23 about supports 24 are connected. The supports 24 lie at the transition between the front engine mount part 25 and rear engine mount part 26 at x1. Here is good to realize that the front engine mount part 25 and the rear engine mount part 26 in the outer load path are different in that they have a different deformation property.
The force F causes a collision-buckling deformation of the motor carrier in an impact 21 itself and the internal deformation structure 22 . 23 . 24 , Thus, at the beginning of Deforma tion an inner and an outer load path on the front engine support member 25 with Fv = Fvm + Ff present.
By ignition of the pyrotechnic element 23 opens the connection between engine mount 21 and the inner longitudinal struts 22 , whereby the load level Fv on the front of the engine mount part 25 , Ff, drops. When the connection is open, the longitudinal struts become 22 shifted in the direction of the deformation path without additional load. Will then the rear engine mount part 26 deformed, so the stiffness or the load level increases again on Fhm, since the rear engine mount part 26 as described, has a stiffer structure, e.g. B. due to a larger wall thickness. Alternatively, the same wall can be used, resulting in no increase in stiffness, but the load level Fv at nominal Fhm = Fvm remains.
To cover different vehicle weights in a product line, for example, adapted stiffness in the inner deformation element 22 . 23 . 24 be used.
10 shows a further embodiment of a crash structure for achieving a step-like deformation behavior. Here is inside the engine mount 27 a mechanical structure 28 . 29 attached firmly to the inner sidewall of the wearer 27 is attached to the first caused by the impact fold-buckling deformation laterally in a bending deformation of the wall of the engine mount 27 to deflect, whereby their stiffness or load level decreases. In this embodiment, the mechanical internal structure is made of a bulkhead plate arranged transversely to the initial deformation direction 28 and one or more diagonally mounted bulkhead plates 29 constructed, with the diagonally arranged partition plates 29 in the deformation direction behind the diagonal, first partition plate 28 are arranged and with this and the side wall of the engine mount 27 are connected.
A force F thus initially causes a fold-buckling deformation of the engine mount 27 , If the deformation is the transversely arranged first partition plate 28 reached at x1, a force is applied transversely to the direction of deformation on the diagonally arranged partition plates 29 , With sufficient lateral force of the carrier kinks 27 lateral and changes its deformation behavior, whereby the load level decreases. This is schematically in 11 shown, wherein the fold-buckling deformation has a load level of Fv = Fa, and that of the kinked engine mount a load level of only Fv = Fb.
To obtain a fundamentally similar deformation behavior as in 11 a crash structure can also be shown in one embodiment 12 use. As with the in 10 embodiment shown here is the engine mount 30 by an internal mechanical element, here: by a one-sided stiffening 31 , changed in its qualitative deformation behavior, namely from a fold-buckling deformation to a bending deformation.
The force F first causes a fold-buckling deformation of the engine mount 30 , If the deformation at x1 is the one-sided stiffening 31 has reached, creates a transverse force, which leads to a bending of the carrier 30 leads. Here is the front end 10 of the engine mount 30 with a reinforcing element 32 provided so that not the front side 10 Excited before the bending deformation started. 3 , With sufficient lateral force, the carrier buckles and changes its deformation behavior, whereby the load level drops, as already schematically in 11 shown.
of the transition
from a fold-bump into a bending deformation can in one
other, not shown, embodiment
For example, diagonal beads are used
13 shows a further embodiment of a crash structure with step-shaped deformation behavior.
The engine mount 33 now has at its front end an at least partially conical opening 34 on, in which an insert element 35 is inserted, which may be itself functional part of the engine mount. The insert element 35 is longitudinally displaceable along the direction of deformation indicated here by the force F. The insert element 35 has a front, stiffer part 36 and a rear, less stiff part 37 on, in the undeformed state, the front part closes 36 an inner chamber 38 and stands here in this. Side of the opening 34 is the outer side wall of the engine mount 33 with reinforcements, z. B. circumferential reinforcing bands 39 , for lateral reinforcement of the engine mount 33 in this area equipped.
In an impact, the force F causes displacement of the insert element 35 in the outer fixed engine mount 33 , Upon contact of the conical surfaces of the insert element 35 with the reinforced wall of the engine mount 33 creates a high load level until the tapered portion of the insert element 35 through the opening 34 has been pushed, according to the in 14 shown load level Fv = Fk. In the further deformation path the load level drops to F1 ( 14 ), since now the insert element 35 is moved almost without drag and the load bearing only through the outer wall of the engine mount 33 happens. However, if the insert element 35 with the front, deformable part 36 the end wall 2 reached, comes through this part 36 added inner load path, so that the load level increases to Fm.
The load level Fk can, for example, by additional reinforcements, the outside of the engine mount 33 are attached, and by the rigidity of the front, deformable part 36 of the insert element 35 be varied, as in 14 indicated by the two arrows of Fk.
The above exemplary schematic embodiments are not
intended to limit the invention to the features shown. Much more
are all embodiments
of the invention, which fall within the scope of the appended claims.
the load levels through design interpretations in a wide range
different sections are reversed. For example, load levels can
between a front part and a rear part as needed
a deformation fall, remain the same or rise. So can
For example, a valve for controlling a discharge behavior
also its flow cross section
zoom in instead of zooming in as shown.
It is clear to the person skilled in the art that the embodiments encompassed by the invention
not for use with a one-sided or even from scratch
are. The expert is in the design of the structural elements or
Crash structure with knowledge of the basic teaching of the invention
also more complex, z. B. multi-sided, force applications can take into account, for.
B. by using conventional
arithmetic aids, such. B. of finite element methods.
Of course it is
the invention is not limited to the example selected for illustration engine mount, but
includes all structural elements,
which may be subject to deformation, in particular so-called
Crash structures, which are used for the interpretation of a deformation behavior
become. Other crash elements include z. B. rear carrier to
Collision protection, parallel to the engine mount arranged support carrier and / or
specially designed deformation elements, so-called "defo boxes". Especially, the invention
suitable to be used with a deformation element,
the one connection of a bumper cross member with
the motor carrier produces.
is an equipment
and installation of controls, sensors, electrical circuits
(eg microprocessors, microcontrollers, etc.) and wiring,
Power supply etc. known to the person skilled in the art and need not be carried out,
although such elements are naturally present when needed.
the switchable crash structures or impact structures is thus
generally a cost effective
Adjustment of the load levels to the vehicle weight for optimization
the acceleration course and reduction of the occupant loads possible.
with the use of switchable crash structures generally simplified
and standardized restraint systems
be used with the possibility
Common parts and synergy parts for
e.g. To use belt system and airbag in a product line for
the requirements for passive safety in laws and consumer protection tests.
is generally a compact front-end package with optimum use
standing free impact path lengths
suitable front structures for
the optimization of the acceleration curves to reduce the occupant load
the switchable crash structures or impact structures at the beginning of the impact
high initial acceleration, in the middle time range or deformation course
one as possible
low vehicle acceleration and higher accelerations until the vehicle is stationary
as in the middle range.
- engine support 1
- Opening the
- further opening
- engine support
- Piercing element
- engine support
- engine support
- motor carrier
- longitudinal strut
Motor bracket portion
Motor bracket portion
- engine support
- engine support
- reinforcing element
- engine support
- Opening in
- insert element
Part of the insert element
Part of the insert element
- reinforcing straps
- support income
- wheel housing
- A column
- load level
- load level
- load level
through the fluid
- load level
through the fluid
- load level
the rear engine mount
- Total load level
the front engine mount
- Outer load level
the front engine mount
- support beam
- Tunnel striking plate
- heel plate
- Sill reinforcement.
at the passenger compartment
the front end