CN114427589A

CN114427589A - Spring device

Info

Publication number: CN114427589A
Application number: CN202111240067.9A
Authority: CN
Inventors: 托马斯·格哈德斯; 拉尔夫·欣特泽恩; 丹尼尔·曼尼兹; 雷纳·苏谢克; 保罗·赞德伯根; 阿尔贝托·吉雷利康索拉罗; 尼科尔·赞德伯根
Original assignee: Ford Global Technologies LLC
Current assignee: Ford Global Technologies LLC
Priority date: 2020-10-29
Filing date: 2021-10-25
Publication date: 2022-05-03
Also published as: DE102020213644A1; DE102020213644B4

Abstract

The invention relates to a spring device (1) for suspending a wheel suspension element (40) relative to a vehicle body (50). According to the invention, the spring device has a spring element (10) which extends along a torsion axis (A) and has a plurality of torsion portions (11-15) which are arranged radially one behind the other, wherein in each case adjacent torsion portions (11-15) are substantially separated from one another but are connected in a rotationally fixed manner in some regions by connecting portions (16-19), wherein the innermost torsion portion (11) and the outermost torsion portion (15) each have an attachment region (20, 21), and one attachment region (20, 21) is connected to the vehicle body (50) and the other attachment region (20, 21) is connected to the wheel suspension element (40).

Description

Spring device

Technical Field

The invention relates to a spring device.

Background

In the wheel suspensions of modern motor vehicles, different types of springs are used, whereby the actual body is connected to the wheels of the vehicle. In addition to springs made of spring steel, springs made of composite materials, in particular fiber-reinforced plastic materials, are also used. These composite springs have a polymer matrix of plastic or embedded fibers. In this case, for example, a unidirectional or woven layer of glass fibres and/or carbon fibres may be embedded in a thermosetting resin (typically an epoxy resin).

In addition to leaf springs used in particular in rigid axles, coil springs are also widely used. Due to the use of coil springs and associated dampers, the vertical packaging of such wheel suspensions is not optimal, i.e. the required vertical installation space is relatively large. To overcome this problem, torsion springs are used in some applications in which the restoring force is based substantially on torsion rather than bending. The possible uses of torsion springs are limited, since they require a relatively large installation space in the direction of the torsion axis in order to provide a sufficiently large torsion angle with limited permissible torsion stresses. If the spring is arranged in the longitudinal direction, this has a negative effect on the crash performance, since the spring can be considered incompressible. If the spring is mounted in the lateral direction, this may lead to space problems especially in the front axle if the engine is arranged in the front part of the vehicle. Furthermore, if the spring is longer than half the vehicle width, asymmetric motion performance may result. In this case, the springs acting on the left or right side, respectively, must be displaced from each other at a certain distance. This spacing requires a variable distance from the attachment point of the spring to the chassis. This results in an asymmetry in the spring load and thus a variable motion performance from left to right.

DE 1010332 a discloses a torsion bar suspension system in which a torsion bar, which is a component of a lever, is arranged to be movable parallel to the axis of rotation of the lever and is provided with at least two support levers of variable length extending substantially in the same direction. The support lever cooperates with the fixed engagement point to rotate the torsion bar by an angle offset from the angular offset of the lever, depending on the lever length ratio. The torsion bar consists of at least two tubes concentrically located inside each other, the levers of different lengths acting adjacent to each other on their free ends.

DE 3819162 a1 discloses a torsion spring for rotationally fixed connection at both ends to a component which can be rotated in opposite directions and which can be used in particular as a torsion bar spring for a link pivotably mounted in a bearing fixed to the vehicle for moving the wheel or in a continuous track roller at its end remote from the bearing, respectively. At least two thin-walled tubular portions are arranged coaxially with each other and concentrically surrounding each other with a gap. The tubular parts are connected together in a rotationally fixed manner at one end thereof and are thus connected in series as torsion springs, wherein in each case the purpose is to connect to components in a rotationally fixed manner, which components may be arranged at the other end of the tubular parts, which components are rotatable in opposite directions.

FR 964473 a discloses a torsion spring made of a plurality of tubes arranged concentrically to one another, wherein in each case radially adjacent tubes are connected together at the end side. One end of the innermost tube is fixed to the base and one end of the outermost tube is connected to a fork which engages a pin by which the torsion spring is deflectable. The torsion spring serves as a cut-off spring in the circuit breaker.

An energy storage device is disclosed in FR 2841953 a1, which is provided in particular as a replacement for a helical, torsion or leaf spring of a vehicle suspension. The energy storage device has one or more separate cylinders with in each case concentric cylindrical sectors, which are connected by teeth serving as claws for connecting the concentric sectors together or to a relatively moving end structure. The concentric sectors may have longitudinal cuts designed to increase the stiffness of the spring for a given twist angle. Further, the device may have a housing for the segments that is filled with a fluid having a selected viscosity to ensure damping.

US 6382649B 1 discloses a suspension for a wheel in a motor vehicle having a link made of fibre composite material, one end of which is mounted on a chassis via a bearing arrangement and the other end of which secures the wheel, and having a spring arrangement made of fibre composite material which resiliently supports the link on the chassis. The bearing arrangement has a bearing in which a bearing part fastened to the chassis can pivot about a pivot axis relative to a bearing part fastened to the connecting rod. The spring device has a torsion bar suspension which extends coaxially with the pivot axis and which is fastened at one end to the chassis and at the other end to the connecting rod. The torsion bar suspension has two torsion bar springs arranged in series and coaxially with each other, wherein one end of the first torsion bar spring is fastened to the link and the other end is fastened to one end of the second torsion bar spring, the other end of the torsion bar spring being fastened to the chassis. Further, a tubular torsion bar stabilizer surrounds the torsion bar spring and connects the links on opposite sides of the vehicle.

In view of the state of the art explained, there is room for further improvement in optimizing the installation space of the wheel suspension. In particular, it may be desirable to be able to optionally integrate additional functions (e.g. damping or variable suspension).

Disclosure of Invention

The object of the invention is to achieve a wheel suspension which is optimized with regard to installation space.

According to the invention, this object is achieved by a spring device having the features of claim 1, wherein the dependent claims relate to advantageous embodiments of the invention.

It should be mentioned that the features and measures presented separately in the following description can be combined in any technically advantageous manner and disclose further embodiments of the invention. The specification additionally features and details of the invention with reference to the drawings.

The invention provides a spring device for suspending a wheel suspension element relative to a vehicle body. In this case, it is a spring device for a vehicle, more particularly for a wheel suspension of a vehicle. The spring device may be used in a motor vehicle, such as a truck or a passenger motor vehicle, but may also be used, for example, in a trailer without a separate drive. The spring device is assigned to a wheel suspension of the vehicle and can be considered at least partially as part of this wheel suspension. Spring devices are used for the suspension or respectively for the elastic connection of the wheel suspension element to the vehicle body. In this case, the "body" is the generic term for the body, the chassis and optionally the sub-frames of the respective vehicle, i.e. those parts which usually form the sprung mass. The wheel suspension element may in particular be a link which in turn is connected in the assembled state to a wheel carrier on which the wheel is rotatably mounted.

The spring device has a spring element extending along the torsion axis. The spring element may also be denoted as a torsion spring, a torsion spring element or a torsion element. The spring element extends along a torsion axis which may also form an axis of symmetry of the spring element. The spring element is configured to deform in an elastic manner in the event of a torque acting relative to the torsion axis and thus absorb and store energy. At the same time, an opposite torque is naturally generated. In principle, different materials can be used for the spring elements, provided that they have sufficient elastic properties and are also sufficiently suitable for use in the wheel suspension region. In particular, spring steel and composite materials are relevant as materials, especially fiber composite materials. Such fiber composites have fibers, such as glass fibers, carbon fibers and/or aramid fibers, embedded or separately incorporated to reinforce a polymer matrix (e.g., a plastic or synthetic resin matrix made of epoxy resin, etc.). Optionally, in this case, other particles, layers or components that may not be classified as polymers or fibers may be embedded or attached therein. Different materials may also be used for different parts of the spring element.

The spring element has a plurality of torsion portions arranged radially one behind the other, wherein in each case adjacent torsion portions are substantially separated from one another but are connected in a rotationally fixed manner in some regions by connecting portions. The torsion portions follow each other in the radial direction (wherein the axial direction is defined by the torsion axis), i.e. the first torsion portion, the second torsion portion and optionally further torsion portions can be distinguished from each other in the radial direction from the outside to the inside. These torsion portions are arranged one around the other, i.e. in each case the subsequent torsion portion is arranged around the torsion portion (outwards in the radial direction). It can also be said that the subsequent torsion surrounds the respective preceding torsion radially on the outside. The torsion portions are thereby nested within each other as a whole.

Thus, the second twist and all subsequent twists (if present) have a recess in which all other internal twists are arranged. Typically, these twists may be indicated as tube-like or tubular. The first or respectively innermost torsion portion can also be configured as a tubular or rod-shaped solid. Typically, the cross-section of the torsion portion transverse to the torsion axis is circular, although deviations thereof are conceivable. Furthermore, the torsion portion is usually configured concentrically to the torsion axis. In this case, the torsion portions radially adjacent to one another are substantially separated from one another, i.e. are usually radially spaced apart, but in some regions they are connected together in a rotationally fixed manner by a connecting portion. The connection is usually arranged on the end side in the axial direction, i.e. in the end region of the torsion portion. A rotationally fixed connection is provided with respect to rotation about the torsion axis. The connection between the torsion portion and the connection portion may be provided by a rigid connection, a non-rigid connection and/or a material connection, wherein typically the material connection. For example, the parts may be glued or welded. In this case, the connection portion may be manufactured integrally with the torsion portion or even both torsion portions. It is conceivable, for example, that the entire spring element is manufactured in one piece, for example when the spring element is manufactured from a fiber composite material. By the substantial separation and connection of adjacent torsion portions in some regions, these torsion portions can twist substantially independently of one another, while in some regions torque is transmitted or, respectively, torque is transmitted locally through the connection portion.

In this case, the innermost torsion portion and the outermost torsion portion each have an attachment area. One attachment area is connected to the vehicle body, wherein the other attachment area is connected to the wheel suspension element. The innermost or respectively the first torsion part has an attachment area when viewed in the radial direction. The same applies to the outermost torsion portion, i.e. to the second torsion portion in the case of only two torsion portions, when viewed in the radial direction. The respective attachment area may be part of or connected to the torsion portion described above. The connection is typically rotationally fixed at least relative to the torsional axis. The connection may be produced, for example, by a rigid connection, a material connection and/or a non-rigid connection.

In the spring device according to the invention, the torque which is present between the wheel suspension element and the vehicle body is absorbed by all torsion portions. More specifically, the torque acts on each torsion portion and causes it to twist. However, as a whole, the respective deformations of the torsion portions add together, so that there is overall a greater torsion than a torsion spring of the same length constructed as a solid. In other words, the entire spring element acts in a more torsionally elastic manner than the individual components thereof, which are arranged to some extent in series. Accordingly, it is thus possible to use a spring element which is significantly shorter in the axial direction, as a result of which the required installation space is significantly reduced. That is, in some cases, the spring element is constructed to be larger in the radial direction than a similar torsion spring constructed as a solid, but this is not a problem in most applications. In fact, for typical vehicle applications, the spring element can be embodied very compact and is advantageous in this respect with respect to known embodiments having a helical spring or a leaf spring.

Many advantages of the spring device according to the invention are already achieved by means of two torsions. Advantageously, however, the spring element has at least three torsion portions and at least two connecting portions, wherein the connecting portions are arranged axially alternately on the end sides of the torsion portions. For example, between three and five twists may be provided. In any case, the number of the connecting portions is one less than the number of the torsion portions. The connections are arranged axially alternately on the end side of the torsion portion, i.e. each connection is arranged on the end side, i.e. in the region of one end of the torsion portion, and successive connections are arranged in each case at the opposite end. For example, the first connection portion may be arranged at an end remote from the wheel, whereby the second connection portion is arranged at the wheel-side end, the third connection portion (if present) is in turn arranged at the end remote from the wheel, etc. In cross-section, the torsion portion and the connecting portion as a whole form a meander or corresponding zigzag structure.

In addition to the reduction in length along the torsion axis, the spring means can also achieve other positive effects. Thus, for example, a temporary change of the spring rate is possible. To this end, at least one blocking element may be connected to the vehicle body and adjustable by an actuator to selectively block or release at least a portion of the spring element relative to the vehicle body. The blocking element is connected to the body, wherein the blocking element is adjustable by the actuator at least between two positions. In the first position, no connection to the spring element is provided, so that the spring element can move freely relative to the vehicle body. In the second position, direct or indirect contact between the blocking element and a portion of the spring element is provided, thereby blocking the respective portion with respect to the vehicle body. This results in that all parts of the spring element between this part and the connection to the body no longer participate in torsion, i.e. the effective torsionable component of the spring element is reduced. Thus, the effective torsional stiffness is naturally increased, i.e. the suspension is stiffer for e.g. the assisted kinematics driving mode. In general, the action of the blocking element is based on a rigid connection in the tangential direction, which is produced directly by the respective portion of the spring element or indirectly by means of an insertion element connected rotationally fixed to this portion. The portion may be a twist and/or a connection.

In particular when the spring element has three or more torsions, the possibility of adjustment can be increased by a spring device having a plurality of independently adjustable blocking elements which are designed to block or release different parts of the spring element with respect to the vehicle body. For example, the first blocking element may be designed to block a first connecting portion connecting the first torsion portion and the second torsion portion together, while the second blocking element is designed to block a second connecting portion connecting the second and third torsion portions or the third and fourth torsion portions. Depending on the blocking element used, the effective torsional stiffness and thus the spring rate can be increased more or less.

According to one embodiment, the spring device may have at least one first friction surface connected to the spring element and a second friction surface connected to the vehicle body so as to be adjustable by the actuator and selectively contactable with and disengageable from the first friction surface. In this case, the first friction surface and the second friction surface are surfaces between which (solid) friction can be generated. For this purpose, they may have a particularly increased roughness and/or a specific wear resistance. However, this is not absolutely necessary. In particular, the first friction surface may be part of the spring element and be designed in the same way as the adjacent surface of the spring element. The second friction surface, which may be part of a friction element, is attached to the vehicle body so as to be adjustable by the actuator. By adjustment, the second friction surface can be brought selectively into contact with the first friction surface, so that solid friction is generated, the strength of which can in turn be varied by the contact force, or the second friction surface can be brought out of contact with the first friction surface, so that no friction is generated. By using such a friction means, the spring behavior or the corresponding vibration behavior of the spring means can be influenced in any way. Thus, the position and/or the contact force of the second friction surface may also be changed during vibration, for example to achieve a faster vibration damping. It is also conceivable here for a plurality of second friction surfaces to be connected to the body so as to be adjustable by the actuator and to be able to come into and/or out of contact with different first friction surfaces on the spring element. In some cases, the second friction surface may even be part of the above-mentioned blocking element, and that is, if the friction between the first friction surface and the second friction surface is sufficiently large, the part of the spring element having the first friction surface or respectively connected to it is completely blocked.

A more efficient use of the available installation space can be achieved if the fluid damper is integrated in the spring element. According to such an embodiment, the inner portion of the fill fluid is disposed adjacent to the spring element. In particular, a fluid-filled intermediate space may be arranged between at least two adjacent torsions. The inner space or the respective intermediate space can be filled with any fluid that does not act on the spring element. For example, fluids known in the art for use in shock absorbers may be used herein. In particular, a fluid-filled intermediate space can also be arranged in each case between all adjacent torsions. These intermediate spaces are usually not sealed with respect to each other, i.e. fluid exchange between them is possible. It goes without saying that a fluid-tight seal must be produced from the outside, which can be achieved in the simplest manner by enclosing the entire inner volume of the spring element in the housing. In this case, the housing wall can be formed in part by the outermost torsion portion. The innermost twist can be guided through an opening in the housing which is sealed by a suitable seal. If the spring element causes a movement in the event of a torsion, in particular a relative movement of adjacent torsions, this leads to a correlation with a laminar and/or turbulent flow inside the fluid in the interior or in the respective intermediate space. A damped vibration of the spring element is thus produced without the need to provide an external separate vibration damper.

Depending on the spacing between adjacent twists, significant fluid friction may occur when the twists have smooth surfaces facing each other. More specifically, with small spacing in the radial direction, fluid friction can reach a significant order of magnitude. However, in many cases, the fluid friction can be positively influenced by at least one torsion portion having at least one braking element which projects radially into the intermediate space and is spaced apart from the adjacent torsion portion. The fluid friction can be increased in a targeted manner by means of the braking element which forms an obstacle to the fluid flow. Thus, for example, laminar friction may be increased or the transition to turbulent friction may be accelerated. Preferably, at least one torsion portion has a plurality of braking elements. It is also preferred that two adjacent torsions have in each case at least one braking element. At least one braking element of the inner twist projects outwardly into the intermediate space, and at least one braking element of the outer twist projects inwardly into the intermediate space. The braking element may be configured, for example, in a blade-like, paddle-like or sail-like manner. For example, the braking element can extend in particular in the radial direction, but can also extend obliquely.

The stiffness of the spring element with respect to forces acting transversely to the torsion axis is usually not sufficient to support the wheel with respect to the vehicle body. If such transverse forces occur on the torsion spring due to the construction, the torsion portion connected to the suspension element can be mounted relative to the vehicle body, so that the aforementioned torques can be transmitted to the vehicle body via the bearing arrangement and thus absorbed. According to one embodiment, in each case adjacent torsion portions are rotatably mounted relative to one another by means of radially interposed rotational bearings. In other words, in each case (at least) one rotary bearing is inserted between two radially adjacent torsion portions, so that a rotation of the torsion portions relative to one another is possible. Thus, if more than two torsion portions are provided, a plurality of rotary bearings are provided through which the force is transmitted from one torsion portion to the next, respectively. In this way, the torsion portion, to which the wheel suspension element is attached, is indirectly supported on the vehicle body. The respective rotary bearing is spaced apart from the connection in the axial direction and can in particular be arranged at the end opposite the connection of the two torsion portions. Each rotary bearing may be a simple sliding or rolling bearing (e.g. ball or roller bearing).

In some cases, typically, however, alternatively to the previous embodiments, the first torsion portion may be connected to the vehicle body through a rotary bearing. The bearing may also be a simple sliding bearing or rolling bearing (e.g. ball bearing or roller bearing). This embodiment is advantageous because a reliable guidance of the innermost torsion part can be ensured transversely to the torsion axis by means of a single bearing. It should be taken into account, however, that in some cases the innermost torsion portion must be lengthened in order to provide space for the above-mentioned rotary bearing, so that the length of the spring element increases along the torsion axis. However, forces transverse to the torsion axis can naturally also be absorbed in other ways in the construction of the vehicle suspension under normal circumstances.

The direction of the torsional axis of the vehicle interior (i.e., the direction relative to the vehicle longitudinal axis (X-axis), the vehicle transverse axis (Y-axis), and the vehicle vertical axis (Z-axis)) may be selected in different ways. Typically, the torsion axis is arranged in a horizontal plane (X-Y plane), but may also be tilted in the direction of a vertical axis (Z axis). Thus, for example, a horizontal force component may be generated in addition to a vertical force component. Different orientations may be selected relative to the X-Y plane. For example, the torsion axis may extend in the vehicle longitudinal direction or, respectively, enclose a small angle (for example, a maximum of 30 °) with the vehicle longitudinal direction. According to another preferred embodiment, the torsion axis extends in the vehicle transverse direction (i.e. along the Y-axis), however wherein it does not necessarily extend parallel to the Y-axis. It may also have an angle of, for example, at most 30 ° to the transverse direction of the vehicle, wherein a tilt in the X-direction and Z-direction may be provided. In this case, one of the attachment areas may be connected to the longitudinal link. In particular, it is preferred if the longitudinal links are connected to the attachment areas forming part of the innermost torsion portion. In this case, the innermost torsion portion is connected to the longitudinal link, while the outermost torsion portion is connected to the vehicle body. Due to the larger radial dimension, the outermost twist is generally more suitable for attachment to the vehicle body than to the longitudinal link. The longitudinal links themselves can be configured to be straight, curved and/or inclined backwards. In any case, it extends in the longitudinal direction of the vehicle (i.e. along the X-axis).

Drawings

Further advantageous details and effects of the invention are described in more detail below with reference to exemplary embodiments shown in the drawings, in which,

fig. 1 shows a schematic cross-sectional view of a first embodiment of a spring device according to the invention;

fig. 2 shows a schematic cross-sectional view of a second embodiment of a spring device according to the invention in a first state;

fig. 3 shows a schematic cross-sectional view of the spring device of fig. 2 in a second state;

fig. 4 shows a schematic cross-sectional view of a third embodiment of a spring device according to the invention;

fig. 5 shows a schematic cross-sectional view of a fourth embodiment of a spring device according to the invention;

fig. 6 shows a schematic cross-sectional view of a fifth embodiment of a spring device according to the invention;

fig. 7 shows a schematic cross-sectional view of a sixth embodiment of a spring device according to the invention; and

fig. 8 shows a cross-sectional view along line VIII-VIII in fig. 7.

Detailed Description

In the different figures, identical components always have the same reference numerals, which is why these components are usually described only once.

Fig. 1 shows a schematic cross-sectional view of a spring device of a motor vehicle, such as a passenger motor vehicle or a truck, according to the invention. The longitudinal link 40 extending along the X-axis of the motor vehicle is mounted on the body 50 by means of the spring element 10. The wheel carrier, which is not shown here and in turn rotatably mounts the wheel, is arranged on a longitudinal link 40, which is constructed essentially rigidly in itself.

The spring element 10 is configured symmetrically with respect to the torsion axis a and has a substantially cylindrical shape. As can be seen by way of example in fig. 1, the torsion axis a is oriented parallel to the Y axis of the motor vehicle. The first torsion part 11, which is arranged radially inside with respect to the torsion axis a, has a closed cylindrical shape. A wheel-side attachment area 21 connected to the longitudinal link 40 (for example by a material connection and/or a rigid connection) is configured on the first torsion part 11. Radially outside the first torsion part 11 follows a second torsion part 12 which has a tubular configuration and surrounds the first torsion part 11. The second torsion portion is substantially spaced apart from the first torsion portion 11, but is connected to the first torsion portion 11 at an end opposite to the wheel-side attachment region 21 by the first connection portion 16. In the exemplary embodiment shown here, the first radially extending connecting part 16 is formed in one piece with the second torsion part 12, while the first torsion part 11 is separately prefabricated and then connected to the first connecting part 16 in a rotationally fixed manner (for example by a material connection). This embodiment can be used, for example, when the spring element 10 consists of prefabricated parts made of spring steel and then joined (for example by material joining, i.e. for example welding, gluing or soldering), wherein a rigid connection, for example by means of teeth, is also conceivable. However, the first connection portion 16 may also be prefabricated separately from the two

torsion portions

11, 12, or (for example in the case of being manufactured from a fiber composite material) it may be constructed integrally with the two

torsion portions

11, 12.

The third torsion portion 13 is connected to the second torsion portion 12 through a second connection portion 17. The fourth torsion portion 14 is connected to the third torsion portion 13 through a third connection portion 18. The fifth torsion part 15 is connected to the fourth torsion part 14 through a fourth connection part 19. The connecting portions 16-19 are alternately arranged on the end sides of the torsion portions 11-15 with respect to the axial direction. In other words, the first connecting portion 16 is disposed at the end away from the wheel, the second connecting portion 17 is disposed at the wheel-side end, the third connecting portion 18 is disposed at the end away from the wheel, and the fourth connecting portion 19 is disposed at the wheel-side end. Thus, in cross section, this results in a meandering structure of the spring element 10. The vehicle-side attachment region 20 that is connected to the vehicle body 50 by, for example, a rigid connection and/or a material connection is configured on the fifth torsion portion 15. Although the fifth and thus outermost torsion part 15 is connected rotationally fixed to one side of the body 50, the first torsion part 11 is mounted on the body 50 via a rotary bearing 22 such that it can rotate about the torsion axis a.

The spring element 10 according to the exemplary embodiment of fig. 1 has as an example five twists 11 to 15, which naturally are not intended to be limiting. Alternatively, the number of twists may be adapted to the required requirements.

If forces act on the wheels during operation of the vehicle, this results in a torque in the longitudinal links 40, which in turn acts as a torque on the spring element 10. Since a torque acts on all the torsion portions 11-15, these are in each case twisted, wherein the individual deformations of the torsion portions 11-15 are added together, so that the spring element 10 as a whole acts in a significantly more torsionally elastic manner than if each torsion portion 11-15 were used alone. Due to the nested structure of the spring element 10, the spring element still has a relatively small length along the torsion axis a and can thus be implemented in a very compact manner.

Fig. 2 and 3 show a second embodiment of a spring device 1 according to the invention, which substantially corresponds to the first embodiment and is not further described in this respect. In this case, however, two blocking

elements

30,31 are arranged on the body 50, which blocking elements can be adjusted by an actuator (not shown here) parallel to the torsion axis a relative to the body 50. Fig. 2 shows a first state, in which the first blocking element 30 is in contact with the spring element 10, more particularly with the third torsion portion 13. This process is shown here in a highly schematic manner. For example, the blocking can be achieved by a rigid connection in the tangential direction between the first blocking element 30 and the third torsion portion 13. As a result of the blocking, only twisting of the first, second and third twisting portions 11-13 takes place in the case of a deflection of the longitudinal link 40, while the fourth and

fifth twisting portions

14, 15 do not participate in the twisting. The spring element 10 now acts overall in a less torsionally elastic manner, i.e. the suspension of the motor vehicle becomes stiffer. Depending on the state not shown here, the first blocking element 30 can also be out of contact with the spring element 20, so that all the torsions 11 to 15 can be twisted and the spring behavior corresponds to the first embodiment. As shown in fig. 3, the stiffness of the suspension can be further enhanced by bringing the second blocking element 31 into contact with the spring element 10, more specifically with the first torsion portion 11. Here, too, a rigid connection can be produced in the tangential direction between the second blocking element 31 and the first torsion portion 11. In the case of a deflection of the longitudinal link 40, only the first torsion part 11 is now involved in the torsion, i.e. the spring element 10 acts in the manner of a conventional rod-shaped torsion spring having the dimensions of the first torsion part 11.

Fig. 4 shows a third exemplary embodiment of a spring device 1 according to the invention, which corresponds essentially to the first exemplary embodiment. In this case, however, a friction element 32, which is only schematically illustrated, is provided, which can be adjusted in the axial direction by means of an actuator (not illustrated here). In the situation shown in fig. 4, the first friction surface 10.1 of the spring element is in contact with the second friction surface 32.1 of the friction element 32, so that solid friction occurs. The corresponding friction may result in a complete blocking in a similar manner to the second embodiment, so that the fourth and

fifth torsion portions

14, 15 will be separated from the longitudinal link 40. However, the movability of the two friction surfaces 10.1, 32.1 is still generally provided, whereby firstly a reduced torsion of the fourth and

fifth torsion portions

14, 15 takes place and secondly energy is converted into heat by friction, so that for example vibrations of the spring device 1 can be damped. The performance of the spring element 1 corresponds to the first embodiment if the friction element 32 is adjusted in the axial direction out of contact with the spring element 10.

Fig. 5 shows a fourth embodiment of the spring device 1 according to the invention with a friction element 32, similar to the third embodiment, however, the friction element 32 is dimensioned such that its friction surface 32.1 cooperates with the opposite friction surface 10.1, the friction surface 10.1 being configured on the first torsion part 11, the first connection part 16 and the second torsion part 12. This also results in damping and partial separation of the vibrations of the second through fifth torsion portions 15 from the longitudinal link 40.

Fig. 6 shows a fifth embodiment of a spring device 1 according to the invention, which is substantially similar to the first embodiment and is not further described in this respect. In this case, however, the first torsion part 11 is not mounted directly on the body 50, but instead a total of four swivel bearings 23-26 are provided in each case between adjacent torsion parts 11-15, which produce a support perpendicular to the torsion axis a. In other words, in this case the first torsion part 11 and thus also the longitudinal link 40 is indirectly supported by the swivel bearings 23-26 and the other torsion parts 12-15 on the body 50. Although the number of rotational bearings required in this embodiment increases, the range of the entire spring device 1 in the axial direction can be shortened relative to the first embodiment, since no external rotational bearing 22 is required.

Fig. 7 shows a sixth exemplary embodiment of a spring device 1 according to the invention, which is again similar to the first exemplary embodiment. In this case, however, the fifth torsion part 15 is connected to a closure plate 27, the closure plate 27 extending transversely to the torsion axis a and the first torsion part 11 protruding through the closure plate 27, wherein the intermediate space between the plate 27 and the first torsion part 11 is closed in a fluid-tight manner by means of suitable seals. As a whole, the vehicle body 50, the fifth torsion portion 15, and the closing plate 27 form a fluid-filled casing 28. Thus, in each case a fluid-filled intermediate space 29 is provided between two adjacent torsions 11-15. By the relative movement of the torsion portions 11-15, fluid friction is thus generated which may be based on laminar and/or turbulent flow. In any case, damping occurs in the case of vibrations of the spring device 1, which makes the use of external vibration dampers unnecessary. The strength of the damper may be influenced by different parameters, for example by the spacing of the torsion portions 11-15 from each other and by the viscosity of the fluid.

Other possibilities for increasing the damping can be seen in the sectional view of fig. 8. In this case, each torsion portion 11-15 has blade-like brake elements 35-37, which in each case project into the intermediate space 29. The torsion portion 11 has a series of radially outwardly projecting first braking elements 35. The second torsion portion 12 has a series of second brake elements 36 projecting radially inwardly into the intermediate space 29, and a series of third brake elements 37 projecting radially outwardly. All braking elements 35 to 37 are shown schematically in a simplified manner here and can in fact have different, optionally also complex shapes, by means of which the flow behavior of the fluid can be influenced in a desired manner.

List of reference numerals

1 spring device

10 spring element

10.1 Friction surface

11-15 torsion part

16-19 connecting part

20 vehicle side attachment region

21 wheel-side attachment region

22-26 swivel bearing

27 closure plate

28 casing

29 intermediate space

30,31 blocking element

32 Friction element

32.1 Friction surface

35-37 brake element

40 longitudinal link

50 vehicle body

Torsion axis A

X X axle

Y Y axle

Z Z axle

Claims

1. A spring device (1) for suspending a wheel suspension element (40) relative to a vehicle body (50), the spring device (1) having a spring element (10) which extends along a torsion axis (a) and has a plurality of torsion portions (11-15) which are arranged radially one behind the other, wherein in each case adjacent torsion portions (11-15) are substantially separated from one another but are connected in a rotationally fixed manner in some regions by connecting portions (16-19), wherein the innermost torsion portion (11) and the outermost torsion portion (15) each have an attachment region (20, 21), and one attachment region (20, 21) is connected to the vehicle body (50), and the other attachment region (20, 21) is connected to the wheel suspension element (40).

2. The spring device according to claim 1,

it is characterized in that the preparation method is characterized in that,

the spring element (10) has at least three torsion portions (11-15) and at least two connecting portions (16-19), wherein the connecting portions (16-19) are arranged axially alternately at the end sides of the torsion portions (11-15).

3. Spring device according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

at least one blocking element (30, 31) is connected to the body (50) and is adjustable by an actuator to selectively block or release at least one portion (11-19) of the spring element (10) with respect to the body (50).

4. The spring device according to claim 3,

it is characterized in that the preparation method is characterized in that,

the spring device has a plurality of independently adjustable blocking elements (30, 31), wherein the blocking elements (30, 31) are designed to block or release different parts (11-19) of the spring element (10) relative to the vehicle body (50).

5. Spring device according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the spring device has at least one first friction surface (10.1) connected to the spring element (10) and a second friction surface (32.1), the second friction surface (32.1) being connected to the body (50) in an actuator-adjustable manner and being selectively contactable with and out of contact from the first friction surface (10.1).

6. Spring device according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

a fluid-filled intermediate space (29) is arranged between at least two adjacent torsion portions (11-15).

7. The spring device according to claim 6, wherein,

it is characterized in that the preparation method is characterized in that,

at least one torsion portion (11-15) has at least one braking element (35-37), which braking element (35-37) projects radially into the intermediate space (29) and is spaced apart from the adjacent torsion portion (11-15).

8. Spring device according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

in each case, adjacent torsion portions (11-15) are rotatably mounted relative to one another by means of radially interposed rotary bearings (23-26).

9. Spring device according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the innermost torsion portion (11) is connected to the vehicle body (50) through a rotary bearing (22).

10. Spring device according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the torsion axis (A) extends in a transverse direction (Y) of the vehicle and attachment regions (20, 21) are connected to a longitudinal link (40).