Chassis system, motor vehicle and chassis system operating method

Abstract

The invention relates to a chassis system, a motor vehicle and a chassis system operating method, the chassis system of the motor vehicle comprises a chassis, at least one stop spring which engages one chassis part and the other chassis part or body part in a large elastic retraction stroke range and thereby limits the elastic retraction process, a chassis control device which is configured to estimate a stop spring temperature of the at least one stop spring, the chassis control device being further configured to output a control signal to the chassis and / or to warn the driver when a stop spring limit temperature is reached or exceeded, in this way, the load of the at least one stop spring is reduced and the temperature of the stop spring is reduced to be lower than the limit temperature of the stop spring.

Description

Technical Field

[0001] The invention relates to a chassis system, a motor vehicle and a chassis system operating method. Background Art

[0002] A chassis system, a motor vehicle and a method for operating a chassis system of the type mentioned in the introduction are well known.

[0003] Motor vehicle chassis usually have stop springs, also called jounce buffers, which are an important component of the chassis. When the wheel mounted on the chassis hits an uneven ground and the chassis spring retracts elastically far enough, the stop spring engages shortly before the maximum spring travel is reached. The stop spring prevents the wheel suspension from retracting elastically too quickly to the maximum spring travel, the relatively moving chassis parts from hitting each other hard, and protects passengers, the body and other chassis parts from damage by abutting the mating stop surface. The stop spring absorbs part of the kinetic energy and converts it into heat energy, which is stored in the stop spring material and dissipated to the surrounding environment over time. Such a stop spring is therefore an accumulator. The corresponding stop spring is generally composed of an elastic material such as rubber or polyurethane and is usually installed on the top side of the bumper or on the body of the motor vehicle.

[0004] In particular, in the case of motor vehicles with a race-tuned chassis or motor vehicles with adjustable height, the corresponding stop springs on uneven and / or curved sections of road, when set to a low ground clearance or when set to a short spring travel, come into contact with the mating stop surface more frequently and are compressed more frequently. Due to the frequent short-term intermittent absorption of energy in succession, the stop springs can heat up faster than they can cool, which leads to increased wear of the stop springs. Failure of the stop springs can become a traffic hazard or a danger to the motor vehicle in the event of a chassis breakdown.

[0005] DE10229584A1 discloses an assembly for compensating transverse forces on a MacPherson spring strut, comprising an air spring damper unit, which in turn consists of at least the following components: a cover and a rolling piston, an air spring bellows made of an elastomeric material, wherein the bellows is fixed at both ends to the cover on the one hand and to the rolling piston on the other hand, whereby the air spring bellows encloses a volume-elastic air chamber, wherein the air spring bellows also forms a first hose that can slide along the outer wall of the rolling piston; and a shock absorber, wherein the first hose has a substantially uniform hose width at the rolling piston; wherein the cover has a first contact contour and a second contact contour for the air spring bellows while forming a second hose with a non-uniform hose width, wherein the second hose changes its position only in shaft dynamics and when the pressure changes, in that the second hose here reaches the first contact contour of its maximum hose width as a stop surface, while the second hose here has a second contact contour of a smaller hose width as a non-stop rolling surface. Summary of the invention

[0006] It is therefore an object of the present invention to improve a chassis system, a motor vehicle and a method for operating a chassis system of the type mentioned at the outset in such a way that premature wear of the stop spring is prevented.

[0007] This object is achieved by a chassis system, a motor vehicle and a method for operating a chassis system.

[0008] A chassis system of a motor vehicle is described, comprising: a chassis; at least one stop spring, which engages a chassis component on the one hand and another chassis component or a body component on the other hand within a large elastic retraction travel range and thereby limits the elastic retraction process; a chassis control device, which is configured to estimate the stop spring temperature of the at least one stop spring, wherein the chassis control device is further configured to output a control signal to the chassis and / or an alarm to the driver when the stop spring limit temperature is reached or exceeded, so as to relieve the load of the at least one stop spring and cool it to a stop spring temperature below the stop spring limit temperature.

[0009] The chassis of a motor vehicle is a system consisting of various components that work together to ensure driving safety and driving comfort. The main components of the chassis are wheels, wheel carriers, brakes, wheel suspensions, subframes, suspensions, shock absorbers, stabilizers and steering. The suspension serves to dampen the movements of the wheel suspensions and protect the vehicle body from damage. Shock absorbers serve to reduce the vibrations of the suspension and suppress resonant behavior.

[0010] Know the different suspension concepts that can be used in the chassis described here, in particular leaf spring suspension, coil spring suspension, hydraulic and / or gas suspension. In particular, a so-called spring strut with a suspension and a shock absorber can be adopted.

[0011] The stop spring serves to protect the chassis from hard impacts and hard stops of relatively movable, essentially inelastic chassis parts or body parts within a large elastic retraction range, since otherwise they could be permanently deformed and damaged. The stop spring absorbs energy and heats up in the process. The heat is dissipated into the surroundings over time. If the stop spring is compressed very frequently, the heating rate is faster than the heat dissipation and the stop spring rises to a temperature range that changes the stop spring material properties and can thus lead to a changed stop spring behavior on the one hand and damage to the stop spring on the other hand.

[0012] The chassis control device can have a processor and non-volatile memory and be connected to various vehicle systems for processing input data, for example to the vehicle's own data bus system such as a CAN bus system. The chassis control device can be designed as a separate system or integrated into the vehicle control device.

[0013] With the aid of the chassis control device, a number of factors influencing the temperature of the stop spring can be evaluated and countermeasures can be initiated when a limit temperature of the stop spring is reached, at which the function of the stop spring in a specified manner can no longer be guaranteed in the long term, thereby influencing the chassis itself, depending on the design, so that the stop spring is hardly used and can cool down and / or a warning can be issued to the vehicle driver that the limit temperature of the stop spring is about to be reached, has been reached or has been exceeded and a change in driving style can be suggested. The driver himself can then decide whether to change his driving style and drive slower to temporarily relieve the chassis load.

[0014] A first refinement provides that the chassis control device is designed to estimate the energy input into the at least one stop spring and the energy dissipation and to estimate the stop spring temperature from these parameters.

[0015] The stop spring temperature depends on many factors, on the one hand the starting temperature of the stop spring, which generally corresponds to the ambient temperature at the start. The ambient temperature is therefore a starting parameter for estimation. On the other hand, there are parameters that increase the stop spring temperature and other parameters that reduce the stop spring temperature. Among the temperature increase factors are, on the one hand, the energy that is input into the respective stop spring, which originates from dynamic processes such as the elastic retraction speed and the remaining spring travel at the turning point. Among the temperature reduction factors are, in particular, the ambient temperature, the air speed around the stop spring that is related to the driving speed, the material properties of the stop spring and the time over which the stop spring is subjected to the temperature reduction factor.

[0016] The estimation of the stop spring temperature is carried out incrementally, i.e., empirically determined increments with positive or negative values ​​per predetermined time period can be added from the estimated starting temperature, i.e., for example, a certain temperature increase due to an elastic retraction process accompanied by contact and compression of the stop spring, followed by a cooling phase with a cooling rate determined by the ambient temperature and the driving speed, followed by recording of a further elastic retraction process accompanied by contact of the stop spring.

[0017] The corresponding data can be stored in a matrix or a characteristic diagram, which can be used by the chassis control unit to reduce the computational effort.

[0018] A different refinement provides that the chassis control device is connected to the acceleration sensor and / or the speed sensor and / or the temperature sensor and / or the level sensor in a signal-transmitting manner, wherein the chassis control device is designed to estimate the stop spring temperature using the sensor data.

[0019] The relevant sensors can be used for different purposes in the motor vehicle or can be assigned only to the chassis control unit. The data are available at least partially via a data bus system and / or via sensors directly connected to the chassis control unit or integrated therein, depending on the configuration.

[0020] In particular, the data of the acceleration sensor, the speed sensor and the temperature sensor can be used in particular to estimate the energy dissipation of the stop spring from heating up. In particular, the data of the level sensor can be used in addition to the data of the acceleration sensor to estimate the energy input into the stop spring and thus the increase in the stop spring temperature.

[0021] Alternatively or additionally, temperature sensors may be provided for the stop spring, which are integrated into the stop spring, attached thereto or which may be designed, for example, to measure by means of infrared radiation.

[0022] A different refinement provides that the chassis is a height-adjustable chassis which is designed to change the vehicle level of the motor vehicle during driving, wherein the chassis control device is designed to control the adjustment of the vehicle level of the motor vehicle, wherein the control signal is used to increase the vehicle level when a limit temperature of the stop spring is reached or exceeded.

[0023] If the stop spring limiting temperature is to be reached or exceeded, the probability of the stop spring engaging can be reduced by raising the vehicle level so that the stop spring contacts less frequently and can cool below the stop spring limiting temperature.

[0024] For cooling purposes, a second stop spring limit temperature can be defined which is lower than the first stop spring limit temperature.

[0025] A different refinement provides that the chassis control system is designed to lower the vehicle level again after the limit temperature of the stop spring has fallen below.

[0026] According to the aforementioned improvement, it may be a second stop spring limit temperature which is lower than the first stop spring limit temperature in order to prevent pumping of the chassis.

[0027] A different refinement provides that the height-adjustable chassis is a pneumatically spring chassis or a hydraulically height-adjustable chassis.

[0028] Such chassis are level-adjustable and would risk compressing the stop spring at low level settings (eg racing driving style) since the spring travel is not as great.

[0029] A different refinement provides that the chassis component has a stop spring seat, on which the stop spring is seated, wherein another chassis component or body component has a counter-stop surface.

[0030] When the spring is retracted, the stop spring seat moves together with the stop spring to the counter-stop surface until the stop spring contacts the counter-stop surface and is compressed together by the stop spring seat and the counter-stop surface during further movement, thereby increasing the spring stiffness and making the breakdown more uncertain.

[0031] The stop spring seat and / or the counter-stop surface can be arranged on or in the spring strut according to a further development.

[0032] A different refinement provides that the stop spring seat and / or the counter-stop surface can be adjusted towards one another or away from one another as a function of the control signal.

[0033] This means that the relative position of the stop spring seat in the chassis system and / or the relative position of the counter-stop surface in the chassis system is changed, thereby allowing the distance between the stop spring seat and the counter-stop surface to be changed under the same driving state (e.g. stationary under the same level setting conditions).

[0034] The stop spring seat and / or the mating stop surface can be adjusted for this reason, especially by means of a motor. Therefore, an earlier or later stop spring engagement can be obtained, so as to position the chassis or the stop spring.

[0035] A different refinement provides that the at least one stop spring consists of plastic, in particular micro-foamed plastic, in particular micro-foamed polyurethane.

[0036] The material can be adjusted well to the respective requirements and can absorb a lot of energy with compact dimensions.

[0037] A first independent subject matter relates to a motor vehicle having a chassis system of the aforementioned type.

[0038] Another independent subject relates to a method for operating a chassis system, in particular a method for operating a chassis system of the type described above, which has a chassis, wherein at least a stop spring is provided, which engages a chassis component on the one hand and another chassis component or a body component on the other hand within a large elastic retraction travel range, thereby influencing and ultimately limiting the elastic retraction process, wherein a chassis control device is provided, which estimates the stop spring temperature of the at least one stop spring and, when the stop spring limit temperature is reached or exceeded, issues a control signal and / or a warning to the driver in order to relieve the load on the at least one stop spring and cool the stop spring temperature to below the stop spring limit temperature.

[0039] A first refinement provides that the chassis control device estimates the energy input into the at least one stop spring and its influence on the stop spring temperature and the energy dissipation and estimates the stop spring temperature from these parameters.

[0040] A different refinement provides that the chassis control device is connected to the acceleration sensor and / or the temperature sensor and / or the level sensor in a signal-transmitting manner, wherein the chassis control device uses the sensor data to estimate the stop spring temperature.

[0041] A different refinement provides that the chassis is a height-adjustable chassis which is designed to change the vehicle level of the motor vehicle during driving, wherein the control signal causes the vehicle level of the motor vehicle to be adjusted and the vehicle level to be raised when a stop spring temperature is reached or exceeded.

[0042] A different refinement provides that the chassis control system lowers the vehicle level again after the limit temperature of the stop spring has fallen below.

[0043] A different refinement provides that the control signal causes a change in the position of the stop spring relative to the other chassis component or body component in order to increase the distance between the stop spring and the other chassis component or body component. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Further features, details and advantages of the present invention are derived from the following description of exemplary embodiments in conjunction with the drawings, in which: Figure 1 A top view of a motor vehicle having a chassis system according to a first embodiment is shown,

[0045] Figure 2 Show Figure 1 a side view of a motor vehicle,

[0046] Figure 3 a spring strut showing a second embodiment of a chassis system in a first configuration,

[0047] Figure 4 Shown in the second configuration Figure 3 The shock absorber strut,

[0048] Figure 5A and Figure 5B Shown in two states Figure 1 Part of the chassis system, Figure 6 a temperature-time graph showing the stop spring temperature of the stop spring, and

[0049] 7A to 7C Various process diagrams for operating a motor vehicle are shown.

[0050] Reference numerals list

[0051] 2 Motor Vehicles

[0052] 3 Chassis system

[0053] 4,4' shock strut

[0054] 5.1 Compressed air tank

[0055] 5.2 Air compressor

[0056] 6 Stop spring

[0057] 8 Stop spring seat

[0058] 10 Mating stop surface

[0059] 12 Chassis Controls

[0060] 14 Level sensor

[0061] 15 rounds

[0062] 16 Body

[0063] 18 Wheel frame side joint

[0064] d Free spring distance

[0065] H Vehicle level height

[0066] t time

[0067] T Stop spring temperature

[0068] Tg limit temperature of stop spring

[0069] Z elastic retractable axis DETAILED DESCRIPTION

[0070] For the sake of easier understanding, identical or identically acting components are provided with the same reference numerals below.

[0071] Figure 1 A motor vehicle 2 is shown having a chassis system 3 (outlined with dashed lines).

[0072] The chassis system 3 has four spring struts 4. The spring struts 4 are here horizontally adjustable and are designed as air spring struts. In other embodiments, the spring struts can be designed as screw spring struts with hydraulic spring adjustment. A hybrid design is also possible, in which spring struts with spring adjustment are not provided on all axles, for example on one axle in a heavy-duty truck.

[0073] For the horizontal height adjustment, a compressed air tank 5.1 with a pump is provided to move air back and forth between the shock absorber strut 4 and the compressed air tank 5.1. In order to compensate for the lost air, an air compressor 5.2 is provided.

[0074] The shock absorber struts 4 each have a stop spring 6, which is also referred to as a jounce buffer. The stop spring 6 assigned to each shock absorber strut 4 is put into use when the maximum elastic retraction stroke of the corresponding shock absorber strut 4 is about to be reached, in order to prevent a hard impact or hard stop of the shock absorber strut 4. The stop spring 6 increases the spring stiffness shortly before the maximum elastic retraction stroke of the respective shock absorber strut 4, thereby obtaining a progressive spring reinforcement. In addition, the stop spring 6 stores the absorbed kinetic energy in the form of heat energy. The stored heat energy is delivered to the surroundings of the motor vehicle 2 over time, and the stop spring 6 put into use becomes cold again.

[0075] In vehicles with a self-levelling function, it has been found that the stop spring 6 is used more often in the case of a low vehicle level, i.e. the neutral position of the spring strut 4, i.e. the position in which no driving kinematic forces act, than in a higher vehicle level, because the spring strut 4 has less spring travel available in operation at this low vehicle level, but the spring rate for the sensitive response of the chassis system 3 should not be too high near the neutral position. This requires a higher progressiveness and the spring strut 4 retracts elastically further at a low vehicle level than at a high vehicle level. Such low levels are also frequently used in a potential racing driving style, where the dynamic lateral forces are greater than in relaxed driving. In this case, the stop spring 6 can heat up faster than it cools down between two engagement times, so that the stop spring 6 can heat up over time, which leads on the one hand to changed material properties and on the other hand to greater wear.

[0076] The stop spring 6 is made of plastic, in particular micro-foamed polyurethane (MCU), which has very good properties with respect to wear resistance, crack resistance and chemical resistance as well as high tensile strength and low compression set.

[0077] The chassis system 3 has a chassis control device 12, which is used to regulate variables of the chassis system 3, in particular the vehicle level. For this purpose, the chassis control device 12 is first connected to a level sensor 14 on the respective spring strut 4. The level sensor 14 measures the respective level of each wheel 15 and reports it to the chassis control device 12 at short time intervals.

[0078] In addition, the chassis control device 12 is connected to the respective shock absorber struts 4, the compressed air tank 5.1 and the air compressor 5.2, so that the lifting and lowering of the individual shock absorber struts 4 and the entire chassis system 3 can be controlled. Therefore, for example, the pressure in some shock absorber struts 4, such as the two rear shock absorber struts, can be raised or lowered depending on the load to obtain a uniform vehicle level.

[0079] Furthermore, in many embodiments of the chassis control device 12, different vehicle levels can be realized for different driving scenarios, such as off-road programs, racing programs or vehicle levels depending on driving speed, in order to optimize driving safety and comfort. In the latter case, the vehicle level can be raised at low speeds and lowered at high speeds.

[0080] Figure 2 The motor vehicle 2 is shown from a side view.

[0081] The vehicle level H can be determined in various ways, here using the ground clearance.

[0082] Figure 3 An alternative embodiment of a spring strut 4 ′ is shown.

[0083] The shock absorber strut 4' is not Figure 1 The height-adjustable spring strut shown is a spring strut with a constant height. However, in the case of the spring strut 4 ′, the driving behavior can be influenced in that the stop spring 6 engages earlier or later, since the free elastic travel d is adjustable without the stop spring 6 stopping.

[0084] The stop spring 6 is fixed on the stop spring seat 8 by means of a positive fit.

[0085] A counter-stop surface 10 is provided opposite the stop spring 6 and is axially adjustable along the elastic retraction axis Z by means of a motor (not shown). Figure 3 The counter-stop surface 10 is shown in the configuration with maximum free spring travel d, ie the stop spring 6 engages only at the latest possible time, shortly before the maximum spring travel of the spring strut 4 ′ is reached.

[0086] Figure 4 It is shown that the counter-stop surface 10 can be adjusted upwards to reduce the free spring travel d and thus achieve an earlier engagement of the stop spring 6 during elastic retraction. This results in a decisively earlier progressive hardening of the spring strut 4' and a limitation of the elastic travel, but without changing the vehicle level, i.e. the ground clearance. This is particularly relevant when a competitive driving style is desired, such as in racing mode, or when driving dynamics, such as at high speeds, need to be improved in driving safety or when the resonance characteristics of the chassis system on uneven roads need to be changed.

[0087] The spring strut 4 ′ is connected to a chassis control unit (not shown) which carries out the adjustment of the counter-stop surface 10 .

[0088] Figure 5A and Figure 5B The connection of a stop spring 6 in a chassis system 3 is schematically shown, which has a vehicle body 16 and a wheel carrier-side connection 18 that is movable relative to the vehicle body 16. The connection 18 (for example a wheel longitudinal link) is on the one hand indirectly or directly fastened to the vehicle body 16 and on the other hand is movable relative to the vehicle body 16. The stop spring 6 rests on a stop spring seat 8, which is associated with the wheel carrier-side connection 18. The counter-stop surface 10 is correspondingly associated with the vehicle body 16.

[0089] During the elastic retraction process, the wheel carrier-side joint 18 moves together with the stop spring 6 toward the vehicle body 16 until the stop spring 6 engages the mating stop surface 10 and is compressed, as shown in FIG. Figure 5B shown.

[0090] Figure 6 An exemplary stop spring temperature-time graph is shown.

[0091] The stop spring temperature T increases over time t when the stop spring 6 is repeatedly compressed. This occurs when the average heat input per unit time is greater than the heat output per unit time because the heat stored in the stop spring 6 is dissipated to the surroundings.

[0092] When the stop temperature T rises too much and exceeds the limit temperature Tg of the stop spring, the material of the stop spring 6 is damaged, which may not only adversely affect the function of the stop spring 6, but also its service life. Therefore, on the one hand, the change of mechanical properties at higher temperatures must be determined, and on the other hand, the structural changes and lower strength must be determined. Therefore, exceeding the limit temperature Tg of the stop spring should be avoided. The material damage that may occur is irreversible due to the structural changes. The limit temperature Tg of the respective stop spring can be determined by experiments.

[0093] The chassis control device 12 can estimate continuously the stop spring temperature T of the stop spring 6 individually as a function of a series of parameters, such as the energy input per compression of the stop spring 6 and the cooling rate as a function of the ambient temperature and the driving speed.

[0094] The corresponding increments that form the curve shown in the stop spring temperature-time curve are determined empirically by trying a standardized series of load sets and determining the maximum temperature in a standard stop spring sample. This determination can be made, for example, with the aid of a thermal camera. In this case, the points with the highest local temperature can be determined and taken into account. The calculation model of the chassis control device 12 is adjusted according to the standard material properties.

[0095] When the limit temperature Tg of the stop spring is higher than the limit temperature Tg, the chassis control device 12 can start the following steps: 7A to 7C Therefore, different measures can be taken, which can include raising the vehicle level H, increasing the free spring distance d or even warning the driver of the vehicle 2.

[0096] By this countermeasure, the relevant stop spring 6 is basically not engaged, so that more time can be provided for cooling the stop spring 6. It is thus possible to achieve a lower limit temperature Tg of the stop spring and prevent the stop spring 6 from being damaged.

[0097] exist Fig. 7A , a first chassis system operating method is described in which the energy input into the respective stop spring 6 is estimated from the signal of the level sensor 14. From this, the temperature of the stop spring 6 is determined, from which the required level adjustment is calculated, which is required to achieve cooling of the stop spring 6.

[0098] A command to raise the vehicle level H is then output and implemented by the chassis system, for example by pumping more fluid into the hydraulic chassis.

[0099] exist Figure 7B A further method for operating a chassis system 3 is described in , in which the energy input into the respective stop spring 6 is estimated starting from the signal of the level sensor 14. The temperature of the stop spring 6 is determined from this, from which the required level adjustment is calculated, which is required to achieve cooling of the stop spring 6.

[0100] A command is then output for raising the vehicle level H and is executed by the chassis system 3 by pumping more air from the compressed air line 5 . 1 into the spring strut 4 .

[0101] exist Figure 7C A third method for operating the chassis system without a level control function is described in , in which the energy input into the respective stop spring 6 is estimated from the signal of the level sensor 14. From this, the temperature of the stop spring 6 is determined, from which the state of the stop spring 6 is determined. From this, a warning is output to the driver to change the driving style in order to reduce the load on the chassis system.

[0102] The present invention is not limited to one of the above-described embodiments but can be modified in various ways.

[0103] All features and advantages from the description and the drawings, including constructional details, spatial arrangements and method steps, may be essential to the invention both per se and also in various combinations.

Claims

1. A chassis system (3) of a motor vehicle (2), the chassis system (3) comprising: - Chassis (4; 4'), at least one stop spring (6) which, within a large elastic retraction travel range, engages on the one hand a chassis component (8) and on the other hand another chassis component or a body component (10) and thereby limits the elastic retraction process, a chassis control device (12) which is configured to estimate a stop spring temperature (T) of the at least one stop spring (6), wherein: The chassis control device (12) is also configured to output a control signal to the chassis (4; 4') and / or output an alarm to the driver when the stop spring limit temperature (Tg) is reached or exceeded, so as to reduce the load of the at least one stop spring (6) and cool it to a stop spring temperature (T) lower than the stop spring limit temperature (Tg).

2. The chassis system (3) according to claim 1, wherein: The chassis control device (12) is designed to estimate the energy input into the at least one stop spring (6) and the energy dissipation and to estimate the stop spring temperature (T) from these parameters.

3. The chassis system (3) according to claim 1 or 2, wherein: The chassis control device (12) is connected to an acceleration sensor, a speed sensor and / or a temperature sensor and / or a level sensor (14) in a signal transmission manner, wherein the chassis control device (12) is designed to use the sensor data to estimate the stop spring temperature (T).

4. Chassis system (3) according to any one of the preceding claims, wherein: The chassis is a height-adjustable chassis (4) which is designed to change the vehicle level (H) of the motor vehicle (2) during driving, wherein the chassis control device (12) is designed to control the adjustment of the vehicle level (H) of the motor vehicle (2), wherein the control signal is used to increase the vehicle level (H) when the stop spring limit temperature (Tg) is reached or exceeded.

5. The chassis system (3) according to claim 4, wherein: The chassis control device (12) is designed to lower the vehicle level (H) again after falling below the stop spring limit temperature (Tg).

6. Chassis system (3) according to any one of the preceding claims, wherein: The height-adjustable chassis is an air spring chassis (4) or a hydraulic height-adjustable chassis.

7. Chassis system (3) according to any one of the preceding claims, wherein: The chassis component has a stop spring seat (8), on which the stop spring (6) is seated, wherein the other chassis component or body component has a mating stop surface (10), wherein the stop spring seat (8) and / or the mating stop surface (10) can be adjusted to move closer to each other or farther away from each other based on the control signal.

8. A motor vehicle (2) having a chassis system (3) according to any one of claims 1 to 7.

9. A method for operating a chassis system (3) having a chassis (4; 4'), wherein: At least one stop spring (6) is provided, which engages a chassis component (8) on the one hand and another chassis component or body component (10) on the other hand within a large elastic retraction stroke range and thereby influences and ultimately limits the elastic retraction process, wherein a chassis control device (12) is provided, which estimates the stop spring temperature (T) of the at least one stop spring (6) and outputs a control signal and / or an alarm to the driver when the stop spring limit temperature (Tg) is reached or exceeded, so as to relieve the load of the at least one stop spring (6) and cool the stop spring temperature (T) to below the stop spring limit temperature (Tg).

10. The method according to claim 9, wherein: The chassis control device (12) estimates the energy input into the at least one stop spring (6) and its influence on the stop spring temperature (T) and the energy dissipation and estimates the stop spring temperature (T) from these parameters.

11. The method according to claim 9 or 10, wherein: The chassis control device (12) is connected to an acceleration sensor and / or a temperature sensor and / or a level sensor (14) in a signal transmission manner, wherein the chassis control device (12) uses the sensor data to estimate the stop spring temperature (T).

12. The method according to any one of claims 9 to 11, wherein: The chassis is a height-adjustable chassis (4) which is designed to change the vehicle level (H) of the motor vehicle (2) during driving, wherein the control signal causes the vehicle level (H) of the motor vehicle (2) to be adjusted and the vehicle level (H) to be increased when the stop spring temperature (Tg) is reached or exceeded.

13. The method according to claim 12, wherein: The chassis control device (12) lowers the vehicle level (H) again after the temperature falls below the limit temperature (Tg) of the stop spring.

14. The method according to any one of claims 9 to 13, wherein: The control signal causes a change in the position of the stop spring (6) relative to other chassis components or body components (10) to increase the distance between the stop spring (6) and the other chassis components or body components (10).

Images