Torsion bar spring assembly, and method for controlling such a torsion bar spring assembly

Abstract

The invention relates to a torsion bar spring assembly (1) for a vehicle, in particular a commercial vehicle, comprising a frame (4), the torsion bar spring assembly comprising a torsion bar (2) which is mounted on the frame (4) in at least one clamping sleeve (3), wherein the torsion bar spring assembly (1) has a variable torsion spring stiffness (cφ). The torsion bar (2) and at least one further component (5, 8) of the torsion bar spring assembly (1) are mounted so as to be axially movable relative to one another in the direction of a longitudinal axis (LA) of the torsion bar spring assembly (1) in both the positive and negative directions, and can be set in different positions, wherein the variable torsion spring stiffness (cφ) depends on the set positions of the torsion bar (2) and of the at least one further component (5, 8). The invention also relates to a method for controlling the torsion bar spring assembly (1) and to a method for controlling a variant of the torsion bar spring assembly (1).

Description

[0001] Torsion bar spring arrangement and method for controlling such a torsion bar spring arrangement. The invention relates to a torsion bar spring arrangement according to the preamble of claim 1. The invention also relates to a method for controlling such a torsion bar spring arrangement according to the preamble of claims 16 and 19. Torsion bar spring arrangements, e.g., for cushioning a body or body of a vehicle, in particular a commercial vehicle, are known in various designs and are presented in well-known textbooks on automotive engineering. The current state of the art predominantly provides for commercial vehicle suspension using air springs. Compressed air is provided by a compressor carried on the vehicle. The suspension is based on the compressibility of the compressed air in the spring bellows. The spring stiffness can be adapted to the vehicle's load condition by varying the air pressure. In addition,Adjusting the air pressure enables the vehicle level to be regulated. Leaf springs or, more rarely, torsion bar springs are used as a possible alternative to air suspension in the commercial vehicle sector. The problem to be solved is the suspension of commercial vehicles, particularly taking into account the following two requirements regarding level control and vehicle dynamics. Level control is intended to maintain a constant vehicle level under different loading conditions. While driving and when the vehicle is stationary, an adjustment of the vehicle height is necessary. Depending on the loading condition, level control is necessary to ensure the required ground clearance. Raising or lowering the vehicle level is required for various purposes. For example, temporarily raising or lowering the vehicle level when driving over obstacles or when driving through height-restricted areasUnderpasses, tunnels, or bridges. This also includes adjusting the vehicle height (leveling) to local conditions during the loading and unloading of trucks (e.g., due to different levels of stationary loading ramps) or temporarily lowering the vehicle level (kneeling) at bus stops to facilitate passenger boarding and alighting. Broadband vibration isolation is required for vehicle dynamics. With regard to vehicle dynamics during driving, the suspension has the task of ensuring a constant natural frequency of the dynamically loaded vehicle. This requires that the stiffness of the vehicle suspension be adjusted accordingly, depending on the vehicle mass or the vehicle's load condition. Vibrations are excited during driving due to unevenness in the road surface, wind loads, and changes in driving conditions (e.g., acceleration, deceleration, cornering). A disadvantage ofThe disadvantage of conventional air suspension is that the compressed air supply, including its peripherals, requires the inclusion of numerous components (e.g., compressor, air dryer, compressed air reservoir, pressure regulators and sensors, control electronics). A key aspect that justifies this additional effort so far is the fact that the compressed air can often also be used for other purposes (e.g., compressed air brakes). However, given the increasing electrification of commercial vehicles, alternative braking concepts (e.g., electric brakes) are gaining in importance, so that the inclusion of compressed air units for the sole use of air suspension no longer appears justified. The proposed solutions have actually proven themselves. However, there is a constant need for improvements. Therefore, the task is to provide an improved torsion bar spring arrangement. A further task is to develop an improved method for controllinga torsion bar spring arrangement. This object is achieved by the subject matter of claim 1. The methods according to claims 16 and 19 solve the further object. One inventive idea is an adaptive torsion bar spring concept as an alternative to the air suspension of commercial vehicles. In this case, both the requirement of level control and the requirements of vehicle dynamics can be advantageously met. A torsion bar spring arrangement according to the invention for a vehicle, in particular a commercial vehicle, with a frame, comprises a torsion bar which is attached to the frame in at least one clamping sleeve, wherein the torsion bar spring arrangement has a variable torsional spring stiffness. The torsion bar and at least one further component of the torsion bar spring arrangement are mounted axially displaceably relative to one another in both positive and negative directions in the direction of a longitudinal axis of the torsion bar spring arrangement and can be adjusted to respective positions, wherein thevariable torsional spring stiffness depends on the set positions of the torsion bar and the at least one other component. A particular advantage here is that by varying the length of the twisted torsion bar in combination with a continuous variation of the torsional resistance moment, the spring stiffness or natural frequency can be adapted to the respective loading condition of the commercial vehicle. A further advantage over air suspension and the peripherals required for this results from a simplified structure and a smaller number of parts. A method according to the invention for controlling the above-described torsion bar spring arrangement for a vehicle, in particular a commercial vehicle, with a frame, having a torsion bar which is attached to the frame in at least one clamping sleeve, wherein the torsion bar spring arrangement has a variable torsional spring stiffness, with the method steps S1) Providing theTorsion bar spring arrangement with an adjustable torsional spring stiffness, wherein the torsion bar spring arrangement has at least one inner body which is arranged to be displaceably guided in a through-bore of the torsion bar; S2) releasing a locking device of the torsion bar and adjusting a torsional section of the torsion bar in a longitudinal direction of a longitudinal axis of the torsion bar spring arrangement to a length value which corresponds to a specific torsional spring stiffness of the torsion bar spring arrangement, and subsequently locking the torsion bar and rotationally and axially fixing the torsion bar; and S3) adjusting a torsional spring stiffness of the torsion bar spring arrangement after releasing a locking device of the inner body by adjusting the at least one inner body from a first position, in which the torsional section of the torsion bar is free from the inner body and the torsion bar spring arrangement has a first torsional spring stiffness, in the direction of the longitudinal axis of theTorsion bar spring arrangement into a second position in which the inner body is arranged within the torsion section, wherein the second position is assigned to a previously defined second torsional spring stiffness of the torsion bar spring arrangement, and wherein the second torsional spring stiffness of the torsion bar spring arrangement is greater than the first torsional spring stiffness of the torsion bar spring arrangement, and subsequently locking the locking device of the inner body. A further method according to the invention for controlling a variant of the above-described torsion bar spring arrangement for a vehicle provides the following method steps. S1') Providing the torsion bar spring arrangement with an adjustable torsional spring stiffness, wherein the torsion bar spring arrangement has at least one outer body which is displaceably guided both on a profile section of the torsion bar and displaceably guided in a through-bore of the clamping sleeve, as well as a bearing in which a bearingsection of the torsion bar is mounted in a through-bore of the bearing so as to be rotatable about the longitudinal axis of the torsion bar spring arrangement and displaceable in both directions along the longitudinal axis; S2') releasing a locking device of the torsion bar and adjusting a torsion section of the torsion bar in a longitudinal direction of the longitudinal axis of the torsion bar spring arrangement to a length value corresponding to a specific torsional spring stiffness of the torsion bar spring arrangement, and subsequently locking the torsion bar and rotationally and axially fixing the torsion bar; and S3') adjusting a torsional spring stiffness of the torsion bar spring arrangement after releasing a locking device of the outer body and adjusting the outer body from a first position, in which the torsion section of the torsion bar is free from the outer body and the torsion bar spring arrangement has a first torsional spring stiffness, in the direction of the longitudinal axis of the torsion bar spring arrangement into a second position, inwherein the outer body is arranged within the torsion section in the range from the first position to the second position on the torsion bar, wherein the second position is assigned to a predetermined second torsional stiffness of the torsion bar spring arrangement, and wherein the second torsional stiffness of the torsion bar spring arrangement is greater than the first torsional stiffness of the torsion bar spring arrangement, and subsequently locking the locking device of the outer body. In this way, an advantageously simple adjustment of the torsion bar spring arrangement is possible. Advantageous further developments of the invention are specified by the subclaims. In one embodiment, the torsion bar is connected to a lever arm, which introduces a torsional moment onto the torsion bar about the longitudinal axis. This enables a simple interface of the torsion bar arrangement to a frame of a vehicle. A further embodiment provides that theAt least one further component is designed as an inner body, which is arranged in a through-bore of the torsion bar in a torsion-proof and displaceably guided manner with respect to the torsion bar. In one embodiment, the inner body is located within the through-bore of the torsion bar in a first position along a longitudinal axis of the torsion bar spring arrangement when a torsion section of the torsion bar spring arrangement has a first torsion spring stiffness, and is located in a second position when the torsion section of the torsion bar spring arrangement has a total torsion spring stiffness as the inverse of the sum of the inverse of the first torsion spring stiffness and the inverse of a second torsion spring stiffness of the torsion section with inner body. In position X1, the inner body is arranged completely in the torsion section of the torsion bar, and the inverses of the torsion spring stiffnesses of the torsion section and inner body add up along the length of the torsion section.In the intermediate positions, an addition takes place according to the percentage ratios of the torsion section of the torsion bar and the torsion section of the inner body depending on the x-coordinate. In this way, an adjustment of the overall torsional spring stiffness of the torsion bar spring arrangement can advantageously be carried out continuously or in stages. For this purpose, it is provided in a further embodiment that the torsion bar has an outer profile which corresponds to an inner profile of a through-bore of the clamping sleeve, and that the inner body has an outer profile which corresponds to an inner profile of a through-bore. In this way, a profiled clamping of the torsion bar in the circumferential direction can easily enable an adaptation of the static equilibrium position or the vehicle level to the local conditions (e.g., loading ramp, bus stop) for the purpose of level control. In a further embodiment, thisfurther advantageously facilitated in that the torsion bar has a section with an outer profile and a section without an outer profile, wherein a length of the section without an outer profile in the direction of the longitudinal axis is longer than a length of the clamping sleeve in the direction of the longitudinal axis. It is also advantageous if the outer profile of the torsion bar, the inner profile of the clamping sleeve, the inner profile of the torsion bar and the outer profile of the inner body are multi-groove profiles, which are designed, for example, as splined shafts, serrated teeth, polygonal shaft profiles or the like. The semi-finished products for this purpose are commercially available, cost-effective, high-quality components. A further embodiment provides that the clamping sleeve has a locking device which, in one position, fixes the torsion bar and the clamping sleeve axially and rotationally together, and which, in another position, enables an axial and rotational movement of the torsion bar relative to the clamping sleeve. This results in theA particular advantage is that the torsion bar is adjustable not only axially but also radially in the case of level control. In a variant of the torsion bar spring arrangement, it is provided that the at least one further component is designed as an outer body, which has a through-bore in which the torsion bar is arranged in a torsion-proof and displaceable manner, wherein the torsion bar is arranged in the clamping sleeve via the outer body. In this way, it is advantageously possible to also enable an adaptation of the torsion spring stiffness by varying the moment of inertia by axially displacing the outer body along the twisted bar section, i.e. the torsion section. As a result, the outer diameter of the torsion bar is changed by displacing the outer body on the profile section of the torsion bar. In a further embodiment of the variant, the torsion bar is provided with a profile section, which has an outer profile, via the outer body inthe clamping sleeve and is mounted with a bearing section connected to the profile section without an outer profile in a bearing connected to the frame, so that it can rotate and be displaced in the direction of the longitudinal axis. As a result, the outer diameter of the torsion bar can be advantageously changed by moving the outer body on the profile section of the torsion bar, whereby an advantageously simple construction also contributes. The bearing also offers the advantage of supporting the torsion bar in the circumferential direction within the correspondingly profiled outer body. In another embodiment of the variant, it is provided that the clamping sleeve and the bearing are arranged at a fixed bearing distance, whereby the torsion bar with the lever arm between the clamping sleeve and the bearing is arranged displaceably in the direction of the longitudinal axis. This enables a compact and simple construction. In a further embodiment of the variant, the outer profile of theProfile section of the torsion bar with an inner profile of the through-bore of the outer body, and the outer body has an outer profile which corresponds to an inner profile of a through-bore of the clamping sleeve. This construction is also advantageously compact, easy to assemble, and has only a few components. In yet another embodiment of the variant, a torsion section of the torsion bar spring arrangement, which extends from the clamping sleeve to the lever arm, has a first torsional spring stiffness when the outer body pushed onto the profile section of the torsion bar lies outside the area of ​​the torsion section, and the torsion section of the torsion bar spring arrangement has a total torsional spring stiffness as the inverse of the sum of the inverse values ​​of the first torsional spring stiffness and a second torsional spring stiffness of the profile section of the torsion bar with the outer body pushed on. In this way, the torsional stiffness can be continuously or in stepsadvantageously easy to adjust and thus quickly and easily adapted to different applications. A further embodiment of the variant provides that the outer profile of the profile section of the torsion bar, the inner profile of the clamping sleeve, the outer profile and the inner profile of the outer body are multi-groove profiles, which are designed, for example, as splined shafts, serrated teeth, polygonal shafts or the like. This is advantageous because the semi-finished products for this purpose are commercially available, cost-effective, high-quality components. If the torsion bar spring arrangement has an adjustment device, this will enable simple adjustment, which can also make adjustments automatically depending on the loading condition of the associated vehicle. In one embodiment of the method, it is provided that in the method steps S2) loosening and adjusting and S3) adjusting a torsion spring stiffness of the torsion bar spring arrangement, the torsion spring stiffness of theTorsion bar spring arrangement is adjusted continuously and / or in stages. In a further embodiment of the method, further process steps are provided. S4) Release of the locking devices of the torsion bar arrangement and leveling of the frame by moving the torsion bar axially in the direction of the longitudinal axis in the through-bore of the clamping sleeve until an outer profile of the torsion bar no longer engages with an inner profile of the through-bore of the clamping sleeve; S5) Torsion-free rotation of the torsion bar to adjust an oscillation angle / twisting angle ^ or a spring travel and thus a static vehicle level; and S6) Subsequent axial displacement of the torsion bar in the clamping sleeve until the outer profile of the torsion bar is again engaged with the inner profile of the clamping sleeve and locking the torsion bar arrangement by means of the locking devices. This results in the special additional advantage of level control. A specialThe advantage lies in an adaptive torsion bar spring concept as an alternative to air suspension in commercial vehicles. This meets the requirements of both level control and vehicle dynamics. By varying the length of the twisted torsion bar in combination with a continuous variation of the torsional resistance moment, the spring stiffness or natural frequency can be continuously and / or in stages adapted to the respective loading condition of the commercial vehicle. In addition, the profiled clamping of the torsion bar in the circumferential direction enables adaptation of the static equilibrium position or the vehicle level to the local conditions (e.g. loading ramp, bus stop). Compared to the air suspension and the peripherals required for this from the state of the art, this results in a simplified structure combined with a corresponding reduction in assembly time. In one embodiment of the method for controlling the torsion bar suspension variant,In method steps S2') loosening and adjusting and S3') adjusting a torsional spring stiffness (c^) of the torsion bar spring arrangement (1), the torsional spring stiffness (c^) of the torsion bar spring arrangement (1) is adjusted continuously and / or in steps. This is advantageous because it enables simple adaptation to a wide variety of applications. In a further embodiment of the method for controlling the variant of the torsion bar suspension, the following method steps are provided: S4') releasing the locking devices of the torsion bar arrangement and leveling the frame by axially displacing the outer body in the direction of the longitudinal axis until the outer profile of the outer body is no longer engaged with the inner profile of a clamping section of the clamping sleeve and is freely rotatable in an unprofiled recess of the clamping sleeve in a free section (position X3 - X4); S5') torsion-free twisting of the torsion bar to adjust an oscillation angle / twisting angle ^or a spring travel and thus a static vehicle level; and S6') Subsequent axial displacement of the outer body in the clamping sleeve until the outer profile of the outer body is again in engagement with the inner profile of the clamping sleeve and locking of the torsion bar arrangement by means of the locking devices. In this way, an advantageously simple and rapid level adjustment is possible. An embodiment of the invention is described below with reference to the attached drawings. This embodiment merely serves to illustrate the invention using preferred designs, which, however, do not represent the invention exhaustively. In this respect, other embodiments as well as modifications and equivalents of the illustrated embodiments are also feasible within the scope of the claims. There is shown: Figure 1 a schematic perspective view of a first embodiment of a torsion bar spring arrangement according to the invention;Figure 2 shows a schematic side view of the first embodiment according to Figure 1; Figures 3-4 show schematic sectional views along line III / IV according to Figure 2; Figure 5 shows a schematic end view according to arrow A according to Figure 2; Figure 6 shows a schematic longitudinal sectional view of the first embodiment according to Figure 1; Figures 7-8 show schematic representations of a second embodiment of a torsion bar spring arrangement according to the invention; Figure 9 shows a schematic sectional view along line IX-IX according to Figure 8; Figures 10-14 show schematic representations of the second embodiment in different positions; and Figure 15 shows a schematic flow diagram of a method according to the invention. Figure 1 shows a schematic perspective view of a first embodiment of a torsion bar spring arrangement 1 according to the invention. Figure 2 shows a schematic side view of the first embodiment according to Figure 1. Figure 3 shows a schematic sectional view alongLine III of Figure 2. Another schematic sectional view along line IV of Figure 2 is shown in Figure 4. Figure 5 shows an end view according to arrow A of Figure 2. Figure 6 shows a schematic longitudinal sectional view of the first exemplary embodiment of Figure 1. The torsion bar spring arrangement 1 serves to suspend a frame 4 of a vehicle (not shown) relative to a wheel or wheel suspension. The structure can be, for example, a body or a vehicle body of the vehicle. A longitudinal axis LA of the torsion bar spring arrangement 1 runs in an x-direction. The coordinate x is used to illustrate different positions of individual functional components of the torsion bar spring arrangement 1 relative to one another. The torsion bar spring arrangement 1 comprises a torsion bar 2, a clamping sleeve 3 and an inner body 5. All components are mounted so as to be axially displaceable relative to one another in the direction of the longitudinal axis LA. At one end of the torsion bar 2 there is an inlet section 2afor introducing a torsional moment about the longitudinal axis LA. The torsional moment is applied to the torsion bar 2 by a lever arm 6. For this purpose, the lever arm 6 is firmly connected at one end to the end section 2a of the torsion bar 2 in a connecting section 6a. At the other end of the lever arm 6, a recess 6b in the form of a bore is provided for coupling to the vehicle wheel. A cylindrical section with an outer profile 2b adjoins the introduction section 2a of the torsion bar 2 in the negative x-direction. The cylindrical section then merges into an end section 2c without an outer profile in a further negative x-direction. The clamping sleeve 3 has a first end face 3a which faces the lever arm 6. A second end face 3b is opposite the first end face 3a. In the direction of the longitudinal axis LA, a through hole 3c with an inner profile 3d is formed in the clamping sleeve 3. The inner profile 3d of the clamping sleeve 3corresponds to the outer profile 2b of the torsion bar 2 and is in engagement with it. The torsion bar 2 is pushed with its cylindrical section with the outer profile 2b into the through hole 3c in its inner profile 3d. The outer profile 2b along the cylindrical section of the torsion bar 2 serves to mount the torsion bar 2 in the circumferential direction within the clamping sleeve 3 which is fixed in a suitable manner to the frame 4. The clamping sleeve 3 is provided with a locking device (not shown) with which the torsion bar 2 can be fixed within the through hole 3c axially in the direction of the longitudinal axis LA and rotationally about the longitudinal axis LA. It is conceivable, for example, that the inner profile 3d of the clamping sleeve 3 is part of a cylindrical body which is arranged rotatably in a bore in the clamping sleeve 3. This body is arranged coaxially to the clamping sleeve 3 and can be locked or released with it by means of the locking devicein order to enable a relative rotation of the body to the clamping sleeve 3. The torsion bar 2 is formed with a through-bore 2d which extends in the direction of the longitudinal axis LA and has an inner profile 2e. The cylindrical inner body 5 is inserted into this through-bore 2d and has an outer profile 5a which corresponds to and engages with the inner profile 2e of the torsion bar 2. The inner body 5 has ends 5b, 5c. One end 5b protrudes outwards from the torsion bar 2 in the negative direction of the x-axis. The other end 5c is located within the through-bore 2d of the torsion bar 2. This is shown in Figure 6. Figure 6 shows a schematic longitudinal sectional view of the embodiment according to Figure 1. The torsion bar 2 is twisted by a moment introduced by means of the lever arm 6 through a twist angle ^ about the longitudinal axis LA. In this case, a twisted section of the torsion bar 2,which is referred to below as the torsion section 10 of the torsion bar 2, here between the outer end of the inlet section 2a of the torsion bar 2 (position X1) to the end face 3a (position X0) of the fixed clamping sleeve 3. The torsion bar 2 has a torsional stiffness, which is referred to below as the torsional spring stiffness c^ and is dependent as follows on the shear modulus G of the material used, the torsional moment of inertia I and a length x of the torsion section 10 of the torsion bar 2: c^ = GI / x The torsional moment of inertia I here is the polar area moment of inertia Ip, which takes into account the geometry of the cross-section of the torsion bar 2, here the inner radius and outer radius. The length of the torsion section 10 is represented by the variable x. By axially displacing the torsion bar 2 relative to the clamping sleeve 3 in the negative or positive x-direction, a length of the torsion section 10 of the torsion bar 2 and thus a torsional spring stiffness c^varies. This enables adaptive adjustment of the spring stiffness c^ or the natural frequency of the torsion bar 2 to a respective loading condition of the associated vehicle. By axially displacing the inner body 5 within the torsion section of the torsion bar 2, adaptation of the spring stiffness c^ is also made possible by varying the torsional moment of inertia. If the inner end section 5c of the inner body 5 is located outside the torsion section of the torsion bar 2, e.g. in a clamping section 40 of the clamping sleeve 3, the torsional spring stiffness c^ is given by the torsion section 10 of the torsion bar 2. The inner body 5 can be displaced over the entire torsion section 10 of the torsion bar 2, starting from position X0 to position X1 in the direction of the longitudinal axis LA in the through-bore 2d of the torsion bar 2. In this way, a total torsional stiffness c^10 of the torsion bar 2 in the torsion section 10 can be continuouslybe changed. Of course, a stepwise adjustment is also possible. An example of this is shown in Figure 6. The inner body 5 is displaced in the through-bore 2d of the torsion bar 2 such that the inner end section 5c is arranged within the torsion section 10 of the torsion bar 2 in a position X2 between the positions X0 and X1. The torsion section 10 of the torsion bar 2 is divided into two sections, namely a first torsion section 20 (here without inner body 5) and a second torsion section 30 (here with inner body 5). The torsional spring stiffness c^20 of the first torsion section 20 without inner body 5 is smaller than the torsional spring stiffness c^30 of the second torsion section 30 with inner body 5. In this way, by moving the inner body 5 in the torsion bar 2, the total torsional spring stiffness c^10 of the torsion section 10 of the torsion bar 2 from the first position X0 to the end position X1 depending onthe x-coordinate. The total torsional stiffness c^10 of the torsion section 10 is increased from an initial total torsional stiffness c^10 to a final total torsional stiffness c^30 depending on the x-coordinate. The first total torsional spring stiffness c^10 corresponds to the torsional spring stiffness c^ of the torsion section 10 without the inner body 5, and the final total torsional spring stiffness c^30 is the inverse of the sum of the inverse values ​​of the torsional spring stiffness c^10 of the torsion section 10 without the inner body 5 and the torsional spring stiffness c^30 of the torsion section 10 with the inner body 5. The following applies to the total torsional spring stiffness c^10: 1 / c^10(f(x)) = 1 / c^20(f(x)) + 1 / c^30(f(x)) In position X1, the inner body 5 is arranged completely in the torsion section 10 of the torsion bar 2 and the torsional spring stiffnesses of the torsion section 10 and the inner body 5 over the length of the torsion section 10 add up. In the intermediate positionsThe reciprocal values ​​corresponding to the percentage ratios of the first torsion section 20 and the second torsion section 30 are added as a function of the x-coordinate. A further variation of the total torsional spring stiffness c^10 can be achieved by varying the initial length of the torsion section 10. For this purpose, the torsion bar 2 can be pulled out of the clamping sleeve 3 in the positive x-direction or pushed into the clamping sleeve 3 in the negative x-direction. Before pulling out or pushing in, the locking device of the clamping sleeve 3 and torsion bar 2 must be released. The locking device is then locked again when the x-value, which corresponds to a previously defined torsional spring stiffness c^, is reached. By varying the length of the torsion section 10 of the twisted torsion bar 2 in combination with a continuous variation of the torsional resistance moment, the torsional spring stiffness c^ or natural frequency of the torsionalBar spring arrangement 1 can be adapted to the respective loading condition of the commercial vehicle. With regard to leveling of the body or frame 4, it is possible, on the one hand, to axially displace the torsion bar 2 in the positive x-direction of the longitudinal axis LA until the outer profile 2b of the torsion bar 2 no longer engages with the inner profile 3d of the clamping sleeve 3. For example, the profile-free end section 2c of the torsion bar 2 can be extended for this purpose. In other words, the torsion bar 2 has a section with an outer profile 2b and a section (end section 2c) without an outer profile, whereby the section without an outer profile (end section 2c) is longer than the clamping sleeve 3. This then enables the torsion-free rotation of the torsion bar 2 to adjust the oscillation angle / twisting angle ^ or the spring travel and thus the static vehicle level. The adjusted static vehicle level is then fixed. This is done byaxial displacement of the profiled section, i.e., the outer profile 2b of the torsion bar 2, into the inner profile 3d of the clamping sleeve 3 until both are engaged. In the example shown, this occurs in the negative x-direction. In this position, the torsion bar 2 is again locked to the clamping sleeve 3 by means of the locking device. Adjustment of the torsion bar spring assembly 1 by axial displacement of the inner body 5 relative to the torsion bar 2 or of the torsion bar 2 relative to the clamping sleeve 3 can be achieved by an adjustment device, which is not shown here but is easily conceivable. This adjustment device can be designed as an electric motor and also actuates the locking device of the clamping sleeve. This adjustment device can also actuate the level control described above. Automatic adjustment of the torsion bar spring assembly 1 depending on the load condition of the associated vehicle is also possible.conceivable. It is also conceivable that more than one inner body 5 is used. For example, the inner body 5 can be designed with a further axially displaceable inner body, not shown but easily conceivable. The outer profile 2b of the torsion bar 2, the inner profile 3d of the clamping sleeve 3, the inner profile 2e of the torsion bar 2 and the outer profile 5a of the inner body 5 are designed as multi-groove profiles, for example as a splined shaft, serrated tooth, polygonal shaft profile or the like. Figure 7 shows a schematic perspective view of a second exemplary embodiment of a torsion bar spring arrangement 1 according to the invention. Figure 8 shows a schematic side view of the second exemplary embodiment of the torsion bar spring arrangement 1 according to the invention according to Figure 7. Figure 9 shows a schematic sectional view along line IX-IX according to Figure 8. The torsion bar spring arrangement 1 of the second embodiment with the longitudinal axis LA comprises a torsion bar 2,a clamping sleeve 3, a bearing 7, and an outer body 8. The clamping sleeve 3 has, as in the first embodiment, end faces 3a, 3b and the through-bore 3c with the inner profile 3d. The clamping sleeve 3 is also fixed to the frame 4 as in the first embodiment. The bearing 7 is fastened to the frame 4. The bearing 7 has two end faces 7a, 7b and a through-bore 7c. In this example, the through-bore 7c is formed with a circular cross-section. The bearing 7 and the clamping sleeve 3 have a constant bearing distance 50 from one another in the direction of the longitudinal axis LA. The bearing distance 50 here is the distance between the opposite end faces 3a and 7c. All components except for the clamping sleeve 3 and the bearing 7 are mounted so that they can be moved axially relative to one another in both the positive and negative x-direction. The torsion bar 2 comprises the lever arm 6 (as in the first embodiment) for introducing a torsional moment around theLongitudinal axis LA. The lever arm 6 is firmly connected to the torsion bar 2 with its connecting section 6a via the introduction section 2a. The end face 7b of the bearing 7 facing the clamping sleeve 3 forms an axial stop in the positive x-direction for the introduction section 2a and the lever arm 6, as can be seen in Figure 8. In contrast to the first exemplary embodiment, the torsion bar 2 is designed with a solid cross-section without an internal bore. A profile section 2i with an outer profile 2b adjoins the introduction section 2a of the torsion bar 2 in the negative x-direction. This profile section 2i then continues in the negative x-direction to one end of the torsion bar 2. The end of the torsion bar 2 has an end face 2j (shown in Figures 10 to 14). Starting from the introduction section 2a of the lever arm 6, a further section of the torsion bar 2 extends as a bearing section 2f in the positive x-direction opposite to theProfile section 2i through the through-bore 7c of the bearing 7. The bearing section 2f is here provided as a solid cylinder with a circular cross-section and a surface 2g without profiling. The free end of the bearing section 2f has an end face 2h. The bearing section 2f of the torsion bar 2 is thus rotatable in the through-bore 7c of the bearing 7 about the longitudinal axis LA and displaceable along the longitudinal axis LA in both x-directions. The bearing 7 serves to reduce the deflection of the torsion bar 2. The outer profile 2b along the profile section 2i serves to support the torsion bar 2 in the circumferential direction within the correspondingly profiled outer body 8, specifically in a through-bore 8c with an inner profile 8d. In this way, the torsion bar 2 is mounted in the outer body 8 via its profile section 2i in a rotationally fixed manner, but is displaceable along the longitudinal axis LA in both x-directions. One end face 8a of the outer body 8 faces the bearing 7, aThe other end face 8e is located at the free end of the outer body 8. The outer body 8 also comprises an outer profile 8b. The outer body 8 is mounted with its outer profile 8b in the clamping sleeve 3 in a through-bore 3c, which has an inner profile 3d corresponding to the outer profile 8b of the outer body 8, displaceably in both x-directions. Figures 10 to 14 show schematic representations of the second exemplary embodiment in various exemplary positions of the torsion bar arrangement 1. In the various positions of the torsion bar arrangement 1, the torsion bar arrangement 1 has different spring stiffnesses or natural frequencies. The different positions of the torsion bar arrangement 1 are made possible by an axial displacement of the torsion bar 2 with its profile section 2i relative to the clamping sleeve 3 and relative to the outer body 8. Combined intermediate positions are of course also possible. This will be explained in connection with theThis is explained in more detail in the following Figures 10 to 14. The length in the x-direction (longitudinal axis LA) of the twisted section of the torsion bar 2, i.e. the torsion section 10 of the torsion bar 2, and thus the corresponding spring stiffness, is varied. This enables adaptive adjustment of the spring stiffness or the natural frequency of the torsion bar 2 to the respective loading state of the frame 4. By axially displacing the outer body 8 on the profile section 2i of the torsion bar 2, adaptation of the spring stiffness is also made possible by varying the torsional moment of inertia. As a result, the outer diameter of the torsion bar 2 is changed by displacing the outer body 8 on the profile section 2i of the torsion bar 2. Figure 10 shows an example position of the torsion bar arrangement 1. The torsion section 10 of the torsion bar 2 is the twisted section of the torsion bar 2 between the positions X0 and X1. This twisted section is here the distance of theLever arm 6 from its bearing end face 6c, which faces the bearing 7 (position X1), to the end face 3a of the clamping sleeve 3, which faces the bearing (position X0). In the example in Figure 10, the torsion section 10 corresponds to the bearing distance 50 and is composed of the first torsion section 20 (here without outer body 8) and the second torsion section 30 (here with outer body 8) in the direction of the longitudinal axis LA. The clamping sleeve 3 is provided with the inner profile 3d approximately halfway down the through-bore 3c (position X3) in its longitudinal direction, starting at its end face 3a (position X0), which inner profile engages here with the outer profile 8b of the outer body 8. This is the clamping section 40. The other half of the through hole 3c of the clamping sleeve 3 starting at position X3 up to the end face 3b of the clamping sleeve (position X4) has a recess 3e with a diameter that is larger than the outer diameter of the outer profile 8b of theOuter body 8. A shoulder 3f is formed in the transition from the through-bore 8b with the inner profile 3d to the recess 3e. This area with the recess 3e in the longitudinal direction is referred to here as the free section 40a (position X3 - X4). The function of the free section 40a is described in more detail below in connection with Figure 14. The lever arm 6 is in contact with the end face 7b of the bearing 7 (position X1) with its bearing side 6c. The bearing 7 here forms an axial stop for the lever arm 6 and the introductory section 2a of the torsion bar 2 in the positive x-direction. Another position of the torsion bar arrangement 1 is shown in Figure 11. In the position in Figure 11, the torsion bar 2 is displaced in the negative x-direction from the bearing 7 towards the clamping sleeve 3. The lever arm 6 is no longer in contact with the bearing 7. In this position, the torsion section 10 of the torsion bar 2 is only made up of the first torsion section 20 (here without outer body 8) of thePosition X1 to position X2. In other words, the twisted torsion bar section is the first torsion section 20 over a length in the x-direction limited by positions X1 and X2, where position X2 corresponds to position X0. The twisted section of the torsion bar 2, i.e. the torsion section 10 or the first torsion section 20 and the second torsion section 30, is / are dependent on the x-coordinate. The outer body 8, together with the profile section 2i of the torsion bar 2 located in the outer body 8, engages with the outer profile 8b of its end section with the inner profile 3d of the clamping sleeve 3 within the clamping section 40 (position X0 to position X3). Figure 12 shows a setting in which the lever arm 6 rests with its bearing side 6c on the end face 7b of the bearing 7. As shown in Figure 11, the outer body 8 together with the profile section 2i of the torsion bar 2 located in the outer body 8 is also connected to the outerouter profile 8b of its end section engages with the inner profile 3d of the clamping sleeve 3 within the clamping section 40 (position X0 to position X3). In this setting, the torsion section 10 has the entire length of the bearing distance 50 and is simultaneously the first torsion section 20 between the positions X1 and X2 (X0). In other words, the profile section 2i of the torsion bar 2 forms the second torsion section 20 here. A further setting is shown in Figure 13. In this case, the profile section 2i of the torsion bar 2 is arranged in the through-bore 8c of the outer body 8 in the area between the lever arm 6 and the end face 3a of the clamping sleeve 3. The torsion section 10 of the torsion bar 2 has the first torsion section 20 (position X1 to position X2) and the second torsion section 30 (position X2 to position X0). The area of ​​the first torsion section 20 is due to the shape of the introduction section 2a of theTorsion bar 2 is designed without an outer profile 2b. Therefore, the inlet section 2a is not encompassed by the outer body 8 and therefore does not engage with the inner profile 8d of the outer body 8. The lever arm 6 is located with its bearing side 6c on the end face 7b of the bearing 7 at the stop, wherein the outer body 8 engages with its outer profile 8d in the clamping section 40 (position X0 to position X3) in the clamping sleeve 3 with its inner profile 3d. Figure 14 shows an adjustment of the torsion bar arrangement 1 for level control. Here, the outer body 8 is axially displaced in the negative x-direction to such an extent that the outer profile 8b of the outer body 8 is no longer engaged with the inner profile 3d of the clamping section 40 of the clamping sleeve 3, but is freely rotatable in the unprofiled recess 3e of the clamping sleeve 3 in the free section 40a (position X3 - X4). This enables the torsion-free rotation of the torsion bar 2 about the longitudinalaxis LA for adjusting the oscillation angle / twisting angle ^ about the longitudinal axis LA or the spring travel and thus the static vehicle level or the frame 4. The static vehicle level adjusted in this way is then fixed by axially displacing the outer body 8 with its outer profile 8b in the opposite (here positive) x-direction into the clamping section 40 (position X2 to X3) into the inner profile 3d of the clamping sleeve 3 and locking the torsion bar arrangement 1. In the second exemplary embodiment, the torsional spring stiffness of the torsion bar arrangement 1 is varied via a corresponding change in the area moment of inertia at the outer diameter of the torsion bar 2, in contrast to the first exemplary embodiment in which the axially displaceable inner body 5 is inserted into the torsion bar 2. Figure 15 shows a schematic flow diagram of a method according to the invention for controlling the torsion bar spring arrangement 1 of the first embodiment according toFigures 1 to 6. In a first method step S1, a torsion bar spring arrangement 1 with an adjustable torsional spring stiffness is provided, wherein the torsion bar spring arrangement 1 has a torsion bar 2, at least one clamping sleeve 3 and at least one inner body 5, which is arranged so as to be displaceably guided in a through-bore 2d of the torsion bar 2. In a second method step S2, a locking device of the torsion bar 2 is released and a torsion section 10 of the torsion bar 2 is set in a longitudinal direction of a longitudinal axis LA of the torsion bar spring arrangement 1 to a length value that corresponds to a specific torsional spring stiffness c^ of the torsion bar spring arrangement 1. The locking device of the torsion bar 2 is then locked again and the torsion bar 2 is rotationally and axially fixed. The locking device of the torsion bar 2 can, for example, be arranged in the clamping sleeve 3. This is not explained further, but is conceivable.In the third method step S3, a locking device of the inner body 5 is released and the inner body 5 is adjusted from a position X0, in which the torsion section 10 of the torsion bar 2 is free from the inner body 5, in the direction of the longitudinal axis LA of the torsion bar spring arrangement 1 to a position X2, in which the inner body 5 is arranged within the torsion section 10 and a first torsional spring stiffness of the torsion bar spring arrangement is present, wherein the second position X2 is assigned to a previously determined second torsional spring stiffness c^ of the torsion bar spring arrangement 1, and wherein the second torsional spring stiffness c^ of the torsion bar spring arrangement 1 is greater than the first torsional spring stiffness c^ of the torsion bar spring arrangement 1. After this adjustment, the locking device of the inner body 5 is locked again. The locking device of the inner body 5 can be attached to the frame 4, for example, which is not explained further, but is conceivable.The level of the frame 4 is adjusted by first releasing the locking devices of the torsion bar arrangement 1 and then moving the torsion bar 2 axially in the x-direction of the longitudinal axis LA until the outer profile 2b of the torsion bar 2 is no longer engaged with the inner profile 3d of the clamping sleeve 3. Then, a torsion-free rotation of the torsion bar 2 is performed to adjust the oscillation angle / twisting angle ^ or the spring travel and thus the static vehicle level. Subsequently, the torsion bar 2 is pushed back into the clamping sleeve 3 until the outer profile 2b of the torsion bar 2 is engaged with the inner profile 3d of the clamping sleeve 3. In the position thus achieved, the torsion bar 2 is locked to the clamping sleeve 3 by means of the locking device. The adjustment device of the torsion bar spring arrangement 1 can be connected to a control unit which can be operated by a user, whereby an automaticAdaptation of the torsion bar spring arrangement to the vehicle dynamics under different loading conditions, as well as level control, can be carried out. The schematic flow diagram of Figure 15 of the method according to the invention for controlling the torsion bar spring arrangement 1 also applies to the second embodiment according to Figures 7 to 14. However, there are the following differences. In a first method step S1', a torsion bar spring arrangement 1 with an adjustable torsion spring stiffness is provided, wherein the torsion bar spring arrangement 1 comprises a torsion bar 2, at least one clamping sleeve 3 and at least one outer body 8, which is arranged displaceably both on a profile section 2i of the torsion bar 2 and displaceably guided in a through-bore 3c of the clamping sleeve 3, as well as a bearing 7, in which a bearing section 2f of the torsion bar 2 is rotatable in a through-bore 7c of the bearing 7 about the longitudinal axis LA and along the longitudinal axis LA in both x-directions is mounted so that it can be moved. In a second method step S2', a locking device of the torsion bar 2 is released and a torsion section 10 of the torsion bar 2 is set in a longitudinal direction of a longitudinal axis LA of the torsion bar spring arrangement 1 to a length value that corresponds to a specific torsional spring stiffness (c^^) of the torsion bar spring arrangement 1. Then, the locking device of the torsion bar 2 is locked again and the torsion bar 2 is rotationally and axially fixed. The locking device of the torsion bar 2 can, for example, be arranged in the bearing 7. This is not explained further, but is conceivable. In a third method step S3', a torsion spring stiffness c^ of the torsion bar spring arrangement 1 is set by releasing a locking device of the outer body 8 and moving the outer body 8 from a position X0, in which the torsion section 10 of the torsion bar 2 is free from the outer body 8 and the torsion bar spring arrangement 1 has a firsttorsional spring stiffness c^, in the direction of the longitudinal axis LA of the torsion bar spring arrangement 1 into a second position X2, in which the outer body 8 is arranged within the torsion section 10 in the range from the first position X0 to the second position X2 on the torsion bar 2, wherein the second position X2 is assigned to a previously defined second torsional spring stiffness c^ of the torsion bar spring arrangement 1, and wherein the second torsional spring stiffness c^ of the torsion bar spring arrangement 1 is greater than the first torsional spring stiffness c^ of the torsion bar spring arrangement 1, and subsequently locking the locking device of the outer body 5. The locking device of the outer body 8 can, for example, be arranged in the clamping sleeve 3. This is not described further, but is conceivable. Furthermore, a level adjustment of the frame 4 is carried out by moving the outer body 8 axially in the x-direction so far that the outer profile 8b of the outer body 8no longer engages with the inner profile 3d of the clamping section 40 of the clamping sleeve 3, but is freely rotatable in the unprofiled recess 3e of the clamping sleeve 3 in the free section 40a (position X3 - X4). Then, a torsion-free rotation of the torsion bar 2 is carried out to adjust the oscillation angle / twisting angle ^ or the spring travel and thus the static vehicle level. Subsequently, the torsion bar 2 is pushed back into the clamping sleeve 3 until the outer profile 2b of the torsion bar 2 engages with the inner profile 3d of the clamping sleeve 3. In the position thus achieved, the torsion bar arrangement 1 is locked by means of the locking device. The invention is not limited by the exemplary embodiments described above, but can be modified within the scope of the claims. It is conceivable that the bearing 7 can be omitted if, for example, a smaller version is used.

[0002] List of reference symbols 1 Torsion bar spring arrangement 2 Torsion bar 2a Introductory section 2b Outer profile 2c End section 2d Through hole 2e Inner profile 2f Bearing section 2g Surface 2h End face 2i Profile section 2j End face 3 Clamping sleeve 3a, 3b End face 3c Through hole 3d Inner profile 3e Recess 3f Shoulder 4 Frame 5 Inner body 5a Outer profile 5b, 5c End section 6 Lever arm 6a Connecting section 6b Indentation 6c Bearing end face 7 Bearing 7a, 7b End face 7c Through hole 8 Outer body 8a End face 8b Outer profile 8c Through hole 8d Inner profile 8e End face 10, 20, 30 Torsion section 40 Clamping section 40a Free section 50 Bearing distance ^ Torsion angle LA Longitudinal axis S1…S6; S1'…S6' Process step x Coordinate X0, X1, X2, X3, X4 Position

Claims

Claims 1. Torsion bar spring arrangement (1) for a vehicle, in particular a commercial vehicle, with a frame (4), having a torsion bar (2) which is attached to the frame (4) in at least one clamping sleeve (3), wherein the torsion bar spring arrangement (1) has a variable torsional spring stiffness (c^), characterized in that the torsion bar (2) and at least one further component (5, 8) of the torsion bar spring arrangement (1) are mounted axially displaceably relative to one another in both the positive and negative directions in the direction of a longitudinal axis (LA) of the torsion bar spring arrangement (1) and are adjustable to respective positions, wherein the variable torsional spring stiffness (c^) is dependent on the set positions of the torsion bar (2) and the at least one further component (5, 8).Torsion bar spring arrangement (1) according to claim 1, characterized in that the torsion bar (2) is connected to a lever arm (6) which introduces a torsional moment onto the torsion bar (2) about the longitudinal axis LA.

3. Torsion bar spring arrangement (1) according to claim 2, characterized in that the at least one further component (5) is designed as an inner body (5) which is arranged in a through-bore (2d) of the torsion bar (2) so as to be rotationally fixed and displaceably guided with respect to the torsion bar (2). 4.Torsion bar spring arrangement (1) according to claim 3, characterized in that the inner body (5) is in a first position (X0) along a longitudinal axis (LA) of the torsion bar spring arrangement (1) within the through-bore (2d) of the torsion bar (2) when a torsion section (10) of the torsion bar spring arrangement (1) has a first torsional spring stiffness (c^20), and is in a second position (X1) when the torsion section (10) of the torsion bar spring arrangement (1) has a total torsional spring stiffness (c^30) as the reciprocal of the sum of the reciprocals of the first torsional spring stiffness (c^20) and a second torsional spring stiffness (c^^^) of the torsion section (10) with inner body (5).

5. Torsion bar spring arrangement (1) according to claim 3 or 4, characterized in that the torsion bar (2) has an outer profile (2b) which corresponds to an inner profile (3d) of a through-bore (3c) of the clamping sleeve (3). responds, and that the inner body (5) has an outer profile (5a) which corresponds to an inner profile (2e) of a through hole (2d).

6. Torsion bar spring arrangement (1) according to claim 5, characterized in that the torsion bar (2) has a section with an outer profile (2d) and a section without an outer profile, wherein a length of the section without an outer profile in the direction of the longitudinal axis (LA) is longer than a length of the clamping sleeve (3) in the direction of the longitudinal axis (LA).

7. Torsion bar spring arrangement (1) according to one of claims 5 or 6, characterized in that the outer profile (2b) of the torsion bar (2), the inner profile (3d) of the clamping sleeve (3), the inner profile (2e) of the torsion bar (2), and the outer profile (5a) of the inner body (5) are multi-groove profiles, which are designed, for example, as splined shafts, serrated teeth, polygonal shafts, or the like. 8.Torsion bar spring arrangement (1) according to one of claims 3 to 7, characterized in that the clamping sleeve (3) has a locking device which, in one position, fixes the torsion bar (2) to the clamping sleeve (3) axially and rotationally, and which, in another position, enables axial and rotational movement of the torsion bar (2) relative to the clamping sleeve (3).

9. Torsion bar spring arrangement (1) according to claim 1 or 2, characterized in that the at least one further component (8) is designed as an outer body (8) having a through-bore (8c) in which the torsion bar (2) is arranged in a rotationally fixed and displaceably guided manner, wherein the torsion bar (2) is arranged in the clamping sleeve (3) via the outer body (8). 10.Torsion bar spring arrangement (1) according to claim 9, characterized in that the torsion bar (2) with a profile section (2i) having an outer profile (2b) is arranged via the outer body (8) in the clamping sleeve (3) and is mounted with a bearing section (2f) without an outer profile, which is connected to the profile section (2i), in a bearing (7) connected to the frame (4) so that it can rotate and be displaced in the direction of the longitudinal axis (LA).

11. Torsion bar spring arrangement (1) according to claim 10, characterized in that the clamping sleeve (3) and the bearing (4) are in a fixed bearing space. stand (50), wherein the torsion bar (2) with the lever arm (6) is arranged between the clamping sleeve (3) and the bearing (4) so as to be displaceable in the direction of the longitudinal axis (LA).

12. Torsion bar spring arrangement (1) according to claim 10 or 11, characterized in that the outer profile (2b) of the profile section (2i) of the torsion bar (2) corresponds to an inner profile (3d) of the through-bore (8c) of the outer body (8), and that the outer body (8) has an outer profile (8b) which corresponds to an inner profile (3d) of a through-bore (3c) of the clamping sleeve (3). 13.Torsion bar spring arrangement (1) according to claim 12, characterized in that a torsion section (10) of the torsion bar spring arrangement (1), which extends from the clamping sleeve (3) to the lever arm (6), has a first torsional spring stiffness (c^10) when the outer body (8) pushed onto the profile section (2i) of the torsion bar (2) lies outside the region of the torsion section (10), and the torsion section (10) of the torsion bar spring arrangement (1) has a total torsional spring stiffness (c^30) as the reciprocal of the sum of the reciprocals of the first torsional spring stiffness (c^10) and a second torsional spring stiffness (c^20) of the profile section (2i) of the torsion bar (2) with the outer body (8) pushed on.Torsion bar spring arrangement (1) according to one of claims 10 to 13, characterized in that the outer profile (2b) of the profile section (2i) of the torsion bar (2), the inner profile (3d) of the clamping sleeve (3), the outer profile (8b) and the inner profile (8d) of the outer body (8) are multi-groove profiles, which are designed, for example, as a splined shaft, serrated tooth, polygonal shaft profile or the like.

15. Torsion bar spring arrangement (1) according to one of the preceding claims, characterized in that the torsion bar spring arrangement (1) has an adjustment device.

16. Method for controlling a torsion bar spring arrangement (1) for a vehicle, in particular a commercial vehicle, with a frame (4), having a torsion bar (2) which is attached to the frame (4) in at least one clamping sleeve (3), wherein the torsion bar spring arrangement (1) has a variable torsion spring stiffness (c^), wherein the torsion bar spring arrangement (1), after a-. nem of claims 1 to 8 and 15, characterized by the steps: S1) providing the torsion bar spring arrangement (1) with an adjustable torsion spring stiffness, wherein the torsion bar spring arrangement (1) has at least one inner body (5) which is arranged so as to be displaceably guided in a through-bore (2d) of the torsion bar (2); S2) releasing a locking device of the torsion bar (2) and adjusting a torsion section (10) of the torsion bar (2) in a longitudinal direction of a longitudinal axis (LA) of the torsion bar spring arrangement (1) to a length value which corresponds to a specific torsion spring stiffness (c^) of the torsion bar spring arrangement (1), and subsequently locking the torsion bar (2) and rotationally and axially fixing the torsion bar (2); and S3) adjusting a torsion spring stiffness (c^) of the torsion bar spring arrangement (1) after releasing a locking device of the inner body (5) by adjusting the at least one inner body (5) from a first position (X0),in which the torsion section (10) of the torsion bar (2) is free from the inner body (5) and the torsion bar spring arrangement (1) has a first torsion spring stiffness (c^), in the direction of the longitudinal axis (LA) of the torsion bar spring arrangement (1) into a second position (X2), in which the inner body (5) is arranged within the torsion section (10), wherein the second position (X2) is assigned to a previously determined torsion spring stiffness (c^) of the torsion bar spring arrangement (1), and wherein the second torsion spring stiffness (c^) of the torsion bar spring arrangement (1) is greater than the first torsion spring stiffness (c^) of the torsion bar spring arrangement (1), and subsequently locking the locking device of the inner body (5).

17. Method according to claim 16, characterized inthat in the method steps S2) loosening and adjusting and S3) adjusting a torsional spring stiffness (c^) of the torsion bar spring arrangement (1), the torsional spring stiffness (c^) of the torsion bar spring arrangement (1) is adjusted continuously and / or in stages.

18. Method according to claim 16 or 17, characterized by the further method steps: S4) Release the locking devices of the torsion bar arrangement (1) and adjust the level of the frame (4) by moving the torsion bar (2) axially in the direction of the longitudinal axis (LA) in the through-bore (3c) of the clamping sleeve (3) until an outer profile (2b) of the torsion bar (2) is no longer in engagement with an inner profile (3d) of the through-bore (3c) of the clamping sleeve (3); S5) Torsion-free rotation of the torsion bar (2) to adjust a swing angle / twisting angle ^ or a spring travel and thus a static vehicle level; and S6) Subsequent axial displacement of the torsion bar (2) in the clamping sleeve (3) until the outer profile (2b) of the torsion bar (2) is again engaged with the inner profile (3d) of the clamping sleeve (3) and locking the torsion bar arrangement (1) by means of the locking devices.

19. Method for controlling a torsion bar spring arrangement (1) for a vehicle, in particular a commercial vehicle, with a frame (4) having a torsion bar (2),which is mounted in at least one clamping sleeve (3) on the frame (4), wherein the torsion bar spring arrangement (1) has a variable torsional spring stiffness (c^), wherein the torsion bar spring arrangement (1) is designed according to one of claims 9 to 15, characterized by the steps: S1') Providing the torsion bar spring arrangement (1) with an adjustable torsional spring stiffness, wherein the torsion bar spring arrangement (1) has at least one outer body (8) which is displaceably guided both on a profile section (2i) of the torsion bar (2) and displaceably guided in a through-bore (3c) of the clamping sleeve (3), and a bearing (7), in which a bearing section (2f) of the torsion bar (2) is rotatable in a through-bore (7c) of the bearing (7) about the longitudinal axis (LA) of the torsion bar spring arrangement (1) and along the longitudinal axis (LA) in both directions is mounted so that it can be moved,S2') releasing a locking device of the torsion bar (2) and adjusting a torsion section (10) of the torsion bar (2) in a longitudinal direction of the longitudinal axis (LA) of the torsion bar spring arrangement (1) to a length value which corresponds to a specific torsional spring stiffness (c^) of the torsion bar spring, arrangement (1), and subsequent locking of the torsion bar (2) and rotational and axial fixing of the torsion bar (2); and S3') adjusting a torsional spring stiffness (c^) of the torsion bar spring arrangement (1) after releasing a locking device of the outer body (8) and adjusting the outer body (8) from a first position (X0), in which the torsion section (10) of the torsion bar (2) is free from the outer body (8) and the torsion bar spring arrangement (1) has a first torsional spring stiffness (c^), in the direction of the longitudinal axis (LA) of the torsion bar spring arrangement (1) into a second position (X2), in which the outer body (8) is arranged on the torsion bar (2) within the torsion section (10) in the range from the first position (X0) to the second position (X2), wherein the second position (X2) is assigned to a previously determined second torsional spring stiffness (c^) of the torsion bar spring arrangement (1),and wherein the second torsional spring stiffness (c^) of the torsion bar spring arrangement (1) is greater than the first torsional spring stiffness (c^) of the torsion bar spring arrangement (1), and subsequently locking the locking device of the outer body (5).

20. Method according to claim 19, characterized in that in the method steps S2') releasing and adjusting and S3') adjusting a torsion spring stiffness (c^) of the torsion bar spring arrangement (1), the torsion spring stiffness (c^) of the torsion bar spring arrangement (1) is adjusted continuously and / or in steps.

21. Method according to claim 19 or 20, characterized by the further method steps: S4') releasing the locking devices of the torsion bar arrangement (1) and leveling the frame (4) by displacing the outer body (8) axially in the direction of the longitudinal axis (LA) untilthat the outer profile (8b) of the outer body (8) is no longer engaged with the inner profile (3d) of a clamping section (40) of the clamping sleeve (3) and is freely rotatable in an unprofiled recess (3e) of the clamping sleeve (3) in a free section (40a) (position X3 - X4); S5') Torsion-free rotation of the torsion bar (2) for adjusting an oscillation angle / twisting angle ^ or a spring travel and thus a static vehicle level; and, S6') Subsequent axial displacement of the outer body (8) in the clamping sleeve (3) until the outer profile (8b) of the outer body (8) is again in engagement with the inner profile (3d) of the clamping sleeve (3) and locking of the torsion bar arrangement (1) by means of the locking devices.

Images