Method for protecting an occupant in a motor vehicle and motor vehicle

Abstract

The invention relates to a method for protecting an occupant (3) in a motor vehicle (1) in the event of a collision, wherein the motor vehicle (1) has a seat (2) comprising a seat body (4) forming a seat surface and a backrest (5) connected to the seat body (4), the inertial forces acting on the occupant (3) in the event of a collision being transmitted to the backrest (5) by means of a seat belt arrangement (7, 8) such that the backrest swings forward relative to the seat body (4) against the restoring action of the elasticity and / or plastic deformation of at least one part of the backrest (5), wherein the force acting against the forward swing is generated and transmitted to the backrest (5) by means of a force generator (35) and / or the possible maximum swing path of the backrest (5) is limited by means of a limiting device such that, in the presence of a preset reference acceleration, the deviation between the actually present swing path of the backrest (5) and the preset reference swing path is as small as possible.

Description

TECHNICAL FIELD

[0001] The invention relates to a method for protecting an occupant in a motor vehicle in the event of a crash, wherein the motor vehicle has a seat which comprises a seat body forming a seat surface and a backrest which is connected in particular swingably to the seat body, wherein, in the event of a crash, the inertial forces acting on the occupant are transmitted to the backrest by means of a safety belt arrangement, so that the backrest swings forward relative to the seat body against the restoring action of an elastic and / or plastic deformation of at least one (backrest) part of the backrest. BACKGROUND

[0002] The function of the safety belt is to protect the occupant in the event of a severe deceleration, in particular to keep the occupant in the seat. The inertial forces which arise as a result of the mass inertia of the occupant are transmitted by means of the safety belt arrangement to components which are fixed relative to the vehicle, in particular to the vehicle body or to the backrest of the seat on which the occupant is seated.

[0003] Such a safety belt arrangement can be part of a side airbag of the seat, wherein the airbag which restrains the occupant in the event of a crash is connected to the backrest by means of the safety belt. Such a system is known, for example, from DE 10 2018 123 633 A1 and US 2020 / 0 238 944 A1.

[0004] The occupant can also be fastened or belted in directly by the safety belt arrangement. For example, a vehicle seat is known from WO 2019 / 110 477 A1 which has a seat part arranged on a seat base and a backrest which is swingably fixed thereto. Furthermore, a safety belt and a load belt are provided, the safety belt being guided through a belt outlet of the backrest, the load belt being connected on the one hand to a load belt length adjuster and on the other hand to a belt automatic retractor of the safety belt.

[0005] DE 10 2019 108 554 A1 discloses a vehicle seat which has a backrest which is swingably connected to a seat surface, a safety belt being arranged on the backrest. The vehicle seat comprises a damping device for damping the movement of the backrest in the event of a restraint, wherein the damping constant of the damping device is adjusted in accordance with the weight or the size of the vehicle occupant. SUMMARY

[0006] It is an object of the invention to provide an improved vehicle seat concept in the event of a crash.

[0007] According to the invention, within the scope of the first embodiment, this object is achieved in a method of the type mentioned at the outset in such a way that the force acting against the forward swing is generated by means of a force generator and is transmitted to the backrest in such a way that, in the presence of a preset reference acceleration, the deviation between the actually present swing path of the backrest and a preset reference swing path is as small as possible.

[0008] According to the application, within the scope of the second embodiment, this object is achieved in a method of the type mentioned at the outset in such a way that the maximum possible swing path of the backrest is limited by means of a limiting device in such a way that, in the presence of a preset reference acceleration, the deviation between the actually present swing path of the backrest and the preset reference swing path is as small as possible. The first and second embodiments can alternatively or in combination be implemented within the scope of the application.

[0009] The application is based on the idea that, when a negative acceleration or deceleration, in particular acting in the longitudinal direction of the vehicle, occurs in the event of a collision, the energy from the occupant is as effectively as possible discharged to the backrest by means of the forward swing movement of the backrest.

[0010] With regard to the first embodiment, a force generator is provided, the force of which additionally acts against the forward swing movement of the backrest and thus against the inertial force of the occupant, in particular during the swing process.

[0011] With regard to the second embodiment, a limiting device is provided, by means of which, in particular, the currently released swing path or the maximum possible swing limit of the backrest can be adjusted. Before this swing limit is reached, the resetting action only occurs due to plastic and / or elastic deformation of the backrest. At the swing limit, a limiting force is generated which prevents or acts against further swinging of the backrest. For this purpose, the relative position of limiting elements which collide with one another can be adjusted, wherein, upon collision of the limiting elements, further swinging of the backrest is blocked.

[0012] According to the application, by means of the force generated by the force generator and / or by means of the limitation of the maximum possible swing path of the backrest by the limiting device, it can be achieved and is accordingly provided that, in the presence of a preset reference acceleration, the deviation between the actually present swing path of the backrest and the preset reference swing path is as small as possible.

[0013] The swing path can be a swing angle, i.e. the angle between the longitudinal direction or longitudinal axis of the backrest in the unswung state and the longitudinal direction or longitudinal axis of the backrest in the swung state. The swinging of the backrest can take place within the range of the backrest bending. In particular in this case, the swing angle can suitably be defined as the angle between the line between the swing point of the backrest in the unswung state and the uppermost point of the backrest and this line in the swung state.

[0014] The reference swivel path is particularly preferably the swivel path of the backrest which ideally occurs under defined conditions in the case of a crash or during a restraint situation. The method according to the application can therefore achieve that the swivel path of the actually occurring swivel of the backrest can be adapted as well as possible to the reference swivel path, so that a defined forward displacement of the occupant occurs in the case of a restraint situation. The reference swivel path or the reference swivel angle is preferably correspondingly to the farthest forward movement of the backrest in the case of an occupant not coming into contact with fixed parts of the motor vehicle, for example the steering wheel and / or the dashboard. The reference swivel path is in particular a forward displacement of the occupant of between 100 mm and 500 mm, in particular 300 mm, in the case of a crash.

[0015] The reference acceleration can be the motor vehicle acceleration which occurs at a predetermined speed, for example 50 km / h, in the case of a frontal collision of the motor vehicle with a positionally fixed object.

[0016] The backrest can be swivelably connected to the seat body, for example by means of a preferably lockable articulation. The backrest is preferably connected in the rear region to the seat surface formed by the seat body. The swivel axis of the backrest can extend horizontally and in the vehicle transverse direction. The seat backrest and the seat body can have a metal basic structure or frame structure and can in particular be upholstered. The seat body can be connected to the vehicle body by means of a seat base, in particular displaceable longitudinally.

[0017] Preferably, acceleration information relating to the current acceleration of the motor vehicle is determined by means of an acceleration sensor, wherein the force and / or the limitation of the maximum possible swivel path is preset in dependence on the acceleration information. In this embodiment, the force generated or the swivel path limitation can be specifically adapted to the measured current acceleration of the motor vehicle. The acceleration sensor can be a sensor which is already present, the sensor data of which are used for example in connection with the triggering of an airbag.

[0018] The data relating to the acceleration sensor can be specified for detecting whether a crash situation of the motor vehicle is currently present. In particular, it can be checked whether a triggering condition is fulfilled, if the acceleration information indicates that the absolute value of the current acceleration of the motor vehicle exceeds a predetermined acceleration limit value. The acceleration limit value should be chosen sufficiently large so that a crash situation of the motor vehicle is very likely to be present when this acceleration limit value is exceeded. Upon fulfilment of the triggering condition, the force generation by the force generator and / or the swivel path limitation by the limitation device and in particular the triggering of an airbag can be effected or initiated.

[0019] Preferably, in the method according to the invention, a characteristic curve describing the relationship between the current acceleration of the motor vehicle and the force and / or the maximum possible sway distance is preset, and the force and / or the preset maximum possible sway distance limit is generated by means of this characteristic curve. Therefore, the force or sway distance limit currently generated by the force generator is preset using acceleration information. The characteristic curve can be stored in the control device of the motor vehicle, which is designed to execute the method according to the invention.

[0020] The characteristic curve can be preset as an analytical relationship, based on which the force to be generated or the maximum possible swing distance is calculated. The analytical relationship can be a formula used to calculate the force or maximum possible swing distance, or related parameters, such as the voltage to be applied to a force generator configured as a motor. The characteristic curve can also be preset as a lookup table, in which values ​​for force or swing distance limits are preset using acceleration values. The characteristic curve, especially the characteristic curve for the preset force, can be preset based on the occupant's weight or height, determined using the occupant information described below.

[0021] Therefore, in the method according to the invention, occupant information describing the occupant's weight and / or height may be provided and invoked within the vehicle controller, and / or determined by means of sensors, wherein a limit and / or force on the maximum possible sway distance is preset based on the occupant information. The heavier and / or taller the occupant, the greater the energy to be extracted from the occupant in a collision, as well as the greater the occupant's inertial force. This, in principle, leads to a greater sway distance of the backrest in a collision, for example, due to the elasticity of the backrest. This is disadvantageous because, in the case of small and / or light occupants, energy absorption occurs over a shorter sway distance than is theoretically practically available. This, in turn, leads to an unnecessarily increased restraint force acting on small and / or light occupants, given the theoretically larger sway distance. This is disadvantageous because the restraint force should be as small as possible to avoid injury. To overcome this drawback and distribute energy over the largest possible swing path, thus optimizing energy extraction from the occupant, the force generated by the force generator, or the limitation on the maximum possible swing path, is specifically adapted to the occupant's size. Specifically, for example, the greater the occupant's mass and / or height, the greater the force generated by the force generator.

[0022] A first embodiment of the method according to the invention may stipulate that the force is reduced, in particular set to zero, at or after the maximum swing distance of the backrest is reached. Therefore, in the event of a collision or restraint, the acceleration of the vehicle and thus the swing distance of the backrest initially increase. Then, the acceleration of the vehicle reaches its maximum value, and then returns to zero. This force change process, which typically occurs in a collision, usually results in a so-called rebound effect at or immediately after the maximum acceleration and thus the maximum swing distance of the backrest, in which the occupant is thrown back or "slapped back" into the backrest due to the decreasing acceleration force and the still-present reset action at that moment. This adverse effect is avoided or at least mitigated based on the reduction of force or torque at or after the maximum possible deflection of the backrest. The force or torque is preferably set to zero so that the effect remains as small as possible. To determine the point in time when the maximum swing distance is reached, the control device may be designed to evaluate the change in the vehicle's acceleration over time using acceleration information, and at this time check whether a maximum condition is met, which is satisfied when the maximum swing distance is reached. For example, this is the case when the gradient of a vehicle's acceleration becomes zero and its sign changes from positive to negative.

[0023] In addition to the method according to the invention, the invention also relates to a motor vehicle comprising at least one seat having a seat body forming a seat surface and a backrest particularly pivotally connected to the seat body, wherein, in the event of a collision, inertial forces acting on the occupant can be transmitted to the backrest via at least one seatbelt device such that the backrest, resisting elastic and / or plastic deformation of at least one portion of the backrest, pivots forward relative to the seat body. The motor vehicle according to the invention has a control device designed to drive the force generator and / or restraining device of the motor vehicle in such a way that…

[0024] - The force reacting to the forward swing can be generated by a force generator and transmitted to the backrest in this way; and / or

[0025] - The maximum possible swing distance of the backrest can be limited in this way by a limiting device.

[0026] This ensures that, given a preset reference acceleration, the deviation between the actual swing distance of the backrest and the preset reference swing distance is minimized. All the advantages and features described in conjunction with the method according to the invention can also be correspondingly applied to the motor vehicle according to the invention, and vice versa.

[0027] Within the scope of the first embodiment, i.e., if the reaction force acting on the forward swing can be generated by a force generator and transmitted to the backrest, then in the motor vehicle according to the invention, the force generator can be specified as an electromechanical actuator or include an electromechanical actuator. In this case, the force is actively generated or produced. The force generator is preferably an electric motor.

[0028] The force generator can be a damping element or include a damping element. In this case, force is generated or produced passively, i.e., in response to the swinging motion of the backrest. The damping or resetting effect of the force generator can be generated by the damping fluid of the damping element. Here, the resetting effect can be adjusted by changing the damping constant of the damping element, for example by changing the diameter of an opening such as an aperture, through which the damping fluid is forced during the swinging motion of the backrest.

[0029] A force generator can be connected to the backrest via a traction device to transmit the pulling force generated by the force generator to the backrest. The force generator can be connected, particularly within or on the seat body, at a location spaced apart from the backrest or swing axis. The pulling force acts on the traction device fixing point on the backrest, where the traction device is fixed to the backrest. A lever arm is arranged between the swing axis and the pulling force acting on the backrest or the traction device fixing point, such that the torque generated by the pulling force reacts to the occupant's inertial force.

[0030] The pulling device, which is connected to the force generator on one side and fixed to the backrest on the other, is preferably a pull rope, especially a metal pull rope or strap. The pulling device can be guided around at least one steering roller that is fixed, especially rotatably fixed to the seat body or backrest, so that the force transmitted through the pulling device is redirected.

[0031] The traction device may have a first section and a second section. The first section may extend rearward, substantially parallel to the seat surface and with respect to the longitudinal direction of the vehicle, between a force generator arranged within or on the seat body, particularly fixed thereto, and a steering roller. The second section may extend upward, substantially along the longitudinal direction of the backrest, between the steering roller and the traction device fixing point of the backrest. The tension is first transmitted horizontally by the force generator to the steering roller along the traction device. There, the tension is correspondingly turned upward and finally acts on the backrest through the traction device fixing point.

[0032] Within the scope of the second embodiment, i.e., if the maximum possible swing distance of the backrest can be limited by a limiting device, it can be specified in the motor vehicle according to the invention that the limiting device for limiting the maximum possible swing distance of the backrest is connected to the backrest by a locking cord, particularly of metal. When the swing limit is reached, a limiting force that prevents further swing of the backrest or reacts to further swing of the backrest can be generated by the limiting device, and this limiting force can be transmitted to the backrest by the locking cord.

[0033] In particular, it is conceivable that the limiting device has a release mechanism and a column that cannot rotate relative to it, wherein the locking rope is wound around the column, particularly multiple times, between the release mechanism and the fixing point of the backrest's tension device, wherein an additional length of the locking rope can be released by the release mechanism. In this embodiment, it is specified that if the locking rope is under tensile stress between the release mechanism and the fixing point of the tension device, then the backrest swings to its maximum extent. Releasing the additional length of the locking rope can first eliminate this tensile stress, and eliminate it over such a long period that the backrest swings far enough to put the locking rope under tensile stress again. The release mechanism can be or includes a mechanical locking device, particularly having a locking pawl engaged in a locking wheel, wherein the additional length of the locking rope can be released by the locking device, and further release of the locking rope is prevented based on the backrest's swing.

[0034] When a force attempts to further swing the backrest, which is already in its maximum swing state, this force is primarily transmitted to the column, generating a corresponding reaction force that prevents further swinging of the backrest. However, if the locking cord or an additional length of the locking cord is released, the force attempting to further swing the backrest causes the locking cord to move or slip longitudinally around the column, thus no longer providing the corresponding restraining effect.

[0035] Therefore, in terms of the release mechanism, to limit the swing path of the backrest, a force smaller than the force typically acting on the backrest in the event of a collision is sufficient to generate a corresponding reaction force, which is primarily caused by the locking rope winding around the bollard. This effect is roughly similar to that of a ship's mooring line held by a sailor, which winds around the bollard multiple times between the sailor and the ship. If the sailor keeps the line taut between himself and the bollard, the ship is held in place. If the sailor releases the tautness and a section of the line slackens, allowing it to slide around the bollard, the ship can move further away from the bollard.

[0036] According to the present invention, acceleration information related to the current acceleration of the motor vehicle can be determined by means of an acceleration sensor, wherein the control device is designed to drive the release device such that an additional length segment of the locking rope is released in relation to the acceleration information. The released length segment of the locking rope thus defines the current, maximum possible swing distance of the backrest. Therefore, the released length segment causes the backrest to swing forward to a point where the released length segment has completely slipped off the column winding due to the forward swing of the backrest. From this point onward, the locking rope is taut, thereby eliminating any further swing of the backrest as described above.

[0037] Preferably, the relationship between the vehicle's current acceleration and the maximum possible swing distance is predicted using a characteristic curve already described in conjunction with the method according to the invention. Specifically, this characteristic curve can predict the relationship between the current acceleration and the length of a defined segment of the locking rope.

[0038] In the motor vehicle according to the invention, it is conceivable that occupant information describing the weight and / or height of the occupant exists within the scope of the vehicle controller and can be accessed and / or determined by sensors, wherein the control device is designed to preset the limit and / or force of the maximum possible sway distance based on the occupant information.

[0039] If occupant information exists within the vehicle controller and is accessible, then that occupant information can be identified and used at the start of driving, for example, by means of a personalized vehicle key, for identification purposes and within the scope of the vehicle's closing system.

[0040] If occupant information can be determined by sensors, the sensor data can be transmitted to a control unit, which then evaluates the sensor data to determine the occupant information. Specifically, occupant identification can be performed, with occupant information stored in the control unit's memory. An occupant's weight or height can also be determined or measured directly, without using their specific identity.

[0041] If occupant information can be determined by sensors, then it is conceivable that these sensors are weight sensors arranged in or on the seat body. These weight sensors generate sensor signals that describe the pressure acting on the seat body and caused by the occupant's weight. This pressure is related to the occupant's weight, thereby generating occupant information.

[0042] As a sensor, it could be an optical sensor, such as a camera, used to detect image data of the interior space and / or environment of the vehicle. The image data can be transmitted to a control unit and evaluated, for example, by facial recognition software to identify the occupants. Information about the occupants' height can also be determined using the image data.

[0043] The sensor could be a fingerprint sensor designed to detect occupant fingerprints. The corresponding sensor signals can also be used to identify the occupant.

[0044] The seatbelt device can be a three-point seatbelt. In a three-point seatbelt, the seatbelt is anchored at three points on the seat. The first point is located on or in the backrest and, for example, at the location of the retractor. The second and third anchor points are located on the seat body and are typically defined by the end fittings and the location of the seatbelt buckle. Alternatively, the seatbelt device can also be a four-point seatbelt, in which the seatbelt is anchored at four points on the seat. A four-point seatbelt has two lap belts and two shoulder belts, with a central seatbelt buckle specifically provided for securing the belt. Other seatbelt devices, such as two-point, five-point, and six-point seatbelts, are also conceivable; however, they are rarely used in practice.

[0045] The seatbelt device can also be an airbag-type seatbelt device, in which at least one airbag of the seat's airbag is connected to the backrest via the airbag-type seatbelt device. The airbag can be a side airbag of the seat, which typically has airbags located on the left and right sides of the backrest. These airbags are inflated respectively in the event of a collision, enveloping the occupant on the sides and front. In the event of a collision, the airbags restrain the occupant in such a way that the occupant's inertial force is transferred to the airbags and from the airbags to the backrest via the seatbelt device. In particular, each airbag in this seatbelt device includes two straps, one secured to the backrest and the other to the seat body. Such a system is described in DE 10 2018 123 633A1, mentioned at the beginning. Attached Figure Description

[0046] Other advantages, features, and details of the invention will become apparent from the following described embodiments, and with the aid of the accompanying drawings. Herein:

[0047] Figure 1 An embodiment of a motor vehicle according to the present invention is shown, by way of illustrating an embodiment of the method according to the present invention.

[0048] Figure 2 It shows Figure 1 A front view of a motor vehicle seat, with the occupant seated.

[0049] Figure 3 This shows the situation at the beginning of the constraint condition.Figure 2 Side view of the seat.

[0050] Figure 4 This shows the later stage of the constraint condition. Figure 2 Side view of the seat.

[0051] Figure 5 A flowchart illustrating an embodiment of the method according to the present invention is shown, which utilizes... Figure 1 The discussion will focus on motor vehicles.

[0052] Figure 6 Two distinct characteristic curves related to occupant information are shown, illustrating the relationship between current acceleration and the pulling force generated by the force generator.

[0053] Figure 7 A side view of a seat according to another embodiment of a motor vehicle based on the present invention is shown, in which an occupant is seated.

[0054] Figure 8 It shows Figure 7 An enlarged view of the column that restricts the relative rotation of the seat's limiting device.

[0055] Figure 9 A flowchart of another embodiment of the method according to the invention is shown, illustrated by means of a motor vehicle, wherein the seat of the motor vehicle is... Figure 7 As shown in the figure,

[0056] Figure 10 The characteristic curves showing the relationship between the current acceleration and the tension generated by the limiting device are shown. Detailed Implementation

[0057] Figure 1 An embodiment of a motor vehicle 1 according to the present invention is shown, the motor vehicle having two seats 2, namely a driver's seat and a front passenger seat. For clarity, a rear seat is not shown. Details relating to the seat 2, i.e., the driver's seat, are provided by [unclear text]. Figures 2 to 4 Explanation. Figure 2 The front view of seat 2 is shown, with occupant 3 seated inside. Figure 3 and Figure 4 The corresponding side view is shown. The points illustrated in relation to the driver's seat also apply to the front passenger seat in principle.

[0058] Seat 2 includes a seat body 4 and a backrest 5 that is pivotally connected thereto. The backrest is hinged to the seat body via a pivoting hinge, allowing the backrest 5 to pivot about a horizontal axis 6. The pivoting position of the backrest 5 can be adjusted forward and backward and fixed according to the preferences of the occupant 3. The seat body 4 is fixed to the vehicle body in a longitudinally movable manner via a seat base (not shown in detail).

[0059] Seat 2 includes a first seatbelt device 7 and a second seatbelt device 8. For details regarding the first seatbelt device 7, please refer to... Figure 2 Regarding the second seatbelt device 8 (reference 8) Figure 3 and Figure 4 The first seatbelt device 7 is a three-point seatbelt device 9, through which the occupant 3 in the motor vehicle 1 is secured or fastened at the start of driving. The three-point seatbelt device 9 includes a seatbelt 10 secured to the seat 2 at three locations. The first securing location is located in the upper region of the backrest 5. At this location, the seatbelt 10 is guided into the interior of the backrest 5 and connected there to the belt retractor 11. The second securing location is located on the side of the seat body 4, where the seatbelt 10 is secured to the seat 2 by an end fitting 12. The third securing location is located on the side of the seat body 4 opposite to the end fitting 12, where the seatbelt 10 is secured to the seat 2 by a seatbelt buckle 13.

[0060] The second seatbelt device 8 is an airbag-type seatbelt device 14, through which the two airbags of the side airbags 15 of the seat 2 are connected to the backrest 5. In their deflated state, the airbags of the side airbags 15 are housed in storage compartments 16, which are located on the side of the backrest 5. In the event of a collision, the airbags of the side airbags 15 deploy, surrounding the occupant 3 on the sides and front, thus preventing or cushioning the impact on the occupant 3. The inflated airbags... Figure 3 and Figure 4 The two airbags of the side airbag 15 are shown in dashed lines. Each airbag is secured to the seat 2 by two straps 17, wherein each strap 17 is secured to the seat body 4 on one side and to the backrest 5 on the other side.

[0061] Subsequently, with the help of Figure 5 Embodiments of the method according to the present invention are described, and are specifically referenced. Figures 1 to 4 In this case, the method includes steps 18 to 23. A control device 24 for the motor vehicle 1 is provided and designed to perform the method.

[0062] In the first step 18 of this method, occupant information 25 describing the occupant 3's physique, i.e., weight and height, is determined. To detect occupant information 25, the vehicle 1 is unlocked using the occupant 3's personalized key before driving. Here, within the scope of the vehicle controller 26, implemented by the control device 24, which controls the vehicle 1's closing system, identity information describing the occupant 3's identity is detected. Occupant information 25 is stored in the control device 24's database and retrieved using the identity information.

[0063] The identity information and occupant information 25 are additionally determined by means of multiple sensors 27. This additional determination is for verification purposes and is not necessarily required, or can be envisioned as an alternative to the determination via the vehicle controller 26.

[0064] As sensor 27, a weight sensor 28 is provided in the seat body 4, which detects a measurement value describing the pressure applied by the occupant 3 to the seat surface of the seat body 4.

[0065] Furthermore, as sensor 27, an optical sensor 31 or camera is provided, designed to detect image data of the passenger compartment 29 and the environment 30 of the vehicle 1. The image data of the optical sensor 31 used to detect the environment 30 can also be used, in particular, within the scope of the vehicle 1's closing system, for example, for verifying identity information. The image data is evaluated by the control device 24 using image evaluation software.

[0066] In addition, as sensor 27, a fingerprint sensor 32 is provided. Sensor data related to the fingerprint of the occupant 3 is detected by the fingerprint sensor at the start of driving and evaluated by the control device 24 to determine the identity information.

[0067] In the next step 19 of the method, acceleration information 33 describing the current acceleration of vehicle 1 is determined. For this purpose, sensor data from the acceleration sensor 34 of vehicle 1 is transmitted to the control device 24 and evaluated. Acceleration information 33 specifically describes the acceleration currently occurring along the longitudinal direction of the vehicle.

[0068] In the next step 20 of the method, it is checked whether the trigger condition is met. If the acceleration information 33 indicates that the absolute value of the current acceleration of vehicle 1 exceeds a preset acceleration limit, then the trigger condition is met. The acceleration limit is the value that maximizes the probability of a collision involving vehicle 1 when the acceleration limit is exceeded. If the trigger condition is not met, the method returns to step 19, in which the acceleration information 33 is detected or updated.

[0069] If the triggering condition is met, the method continues in step 21. In this step, the airbags of the side airbags 15 are inflated. Furthermore, a force is generated by the force generator 35 and transmitted to the backrest 5. In this embodiment, the force generator 35 is an electromechanical actuator, i.e., a motor, arranged in the seat body 4. The force generator 35 generates a pulling force, which is transmitted to the backrest via a pulling device 36. The pulling device 36 is a metal traction rope or, alternatively, a strap.

[0070] The traction device 36 includes a first section 37 and a second section 38. The first section 37 extends between the force generator 35 and a steering roller 39, which is rotatably arranged in a region behind or at the rear of the seat body 4, around which the traction device 36 is guided. In the first section 37, the traction device 36 is substantially parallel to the seat surface and extends rearward in the longitudinal direction of the vehicle. The second section 38 extends between the steering roller 39 and a traction device fixing point 40, at which the traction device 36 is fixed to the backrest 5. In the region of the second section 38, the traction device 36 extends upward in the longitudinal direction of the backrest 5.

[0071] The purpose of the pulling force and other details are then explained. Therefore, in the event of a collision, an inertial force caused by the occupant's weight acts on occupant 3. This inertial force is transmitted to the backrest 5 via seatbelt devices 7 and 8. Due to this inertial force, the backrest 5 swings forward, wherein... Figure 3 This shows the situation that occurs immediately after the triggering condition is met. Figure 4 The collision situation is shown. Figure 3 Compared to the situation where progress has been made. Clearly, in... Figure 4 In the scenario shown, the inertial force of the occupant 3 causes the backrest 5 to swing forward around the swing axis 6.

[0072] The force generated by the force generator 35 reacts to the forward sway of the backrest 5 caused by inertia. To generate this force, the occupant information 25 is considered such that the greater the weight or height of the occupant 3, the greater the force. Specifically, a preset characteristic curve for the occupant information 25 is used, which shows the relationship between the current acceleration of the vehicle 1 and the magnitude of the force or pulling force of the force generator 35. To determine the current acceleration, the acceleration information 33 is also continuously detected and updated during step 21.

[0073] The relationship between the current acceleration and the magnitude of the force is such that, regardless of the weight or height of the occupant 3, the backrest 5 achieves the longest possible swing distance or swing angle during the collision process. Specifically, the preset characteristic curve is such that, given a fixed reference acceleration of the vehicle 1, the swing angle of the backrest 5 is always as constant as possible, especially regardless of the size of the occupant 3.

[0074] To better understand, a specific example is used below to illustrate how to give the characteristic curve. In this example, the first occupant 3, sitting in the driver's seat, is significantly larger or stronger than the second occupant 3, sitting in the front passenger seat. Therefore, in a collision, the inertial force caused by the first occupant 3 is twice that of the second occupant 2.

[0075] With the help of Figure 6Characteristic curves 44 and 45 (solid lines) associated with the two occupants 3 or their occupant information 25 are illustrated. The horizontal axis 41 of the coordinate system represents the current acceleration of the vehicle 1, and its vertical axis 42 represents the absolute value of the pulling force generated by the force generator 35. The dashed line 43 represents the acceleration limit, which triggers the conditions when this limit is exceeded. Characteristic curves 44 and 45 for the first occupant 3 are designed such that if the limit acceleration 43 is exceeded, the pulling force in the case of the first occupant 3 is twice that in the case of the second occupant 3, because the inertial force of the first occupant 3 is also twice that of the second occupant 3. This results in the backrest 5 having the swing path or swing angle being as similar as possible, or ideally, identical, in both occupants 3. Accordingly, both occupants 3 have the same swing path available for energy absorption, thus minimizing the constraint force in a collision in both cases.

[0076] As already mentioned, during step 21, acceleration information 33 is continuously updated, and in parallel, a check is performed within the scope of step 22 to determine if a maximum condition is met. The maximum condition is met once the acceleration of vehicle 1 and therefore the swaying distance of the backrest 5 have or reach their maximum value. This check is performed by evaluating the change in acceleration of vehicle 1 over time using control device 24, specifically whether the gradient of acceleration becomes zero and whether a change in the sign of the gradient from positive to negative occurs. If the maximum condition is not met, the method continues in step 21, and the pulling force continues to be generated. If the maximum condition is met, the absolute value of the pulling force is reduced, i.e., set to zero. Figure 6 In this example, the maximum condition is met when the acceleration shown by the dashed line 46 is reached. By subsequently cutting off the tension, the occupant 3 is prevented from being thrown back or slapped back into seat 2 at the end of the collision due to the so-called rebound effect.

[0077] Additionally, regarding the force generator 35, it should be noted that in the described embodiment, the force generator results in the active generation of force. Alternatively, the force generator 35 may also be a damping element, particularly utilizing a damping fluid, wherein the generated force or torque is passively generated in response to the oscillating motion of the backrest 5. In this case, the characteristic curves 44, 45 or the corresponding force change process are adjusted by regulating the damping factor of the damping element.

[0078] Figure 7 A seat 2 according to another embodiment of the motor vehicle 1 according to the present invention is shown, wherein the same parts are provided with the same reference numerals, and therefore the description in this respect, in conjunction with the embodiments described above, is equally applicable here. The seat 2 of Figure 7 The view shown is the same as Figure 4 The view or situation shown is equivalent to that in Figure 7In addition to the second seat belt device 8, the seat 2 also has a first seat belt device 7, although this is not shown further.

[0079] Figure 7 The seat 2 shown differs from the embodiment described above in that a limiting device 47, fixed to the seat body 4, is provided instead of the force generator 35. The limiting device 47 allows adjustment of the current released swing distance of the backrest 5, i.e., the maximum possible swing limit. Before reaching the swing limit, the resetting action is achieved solely through the initial elastic deformation and subsequent plastic deformation of the backrest 5. Upon reaching the swing limit, the backrest 5 cannot swing further.

[0080] This can be achieved by connecting the limiting device 47 to the backrest 5 via a metal locking cord 48. When the swing limit is reached, the locking cord 48 is under tensile stress, wherein a corresponding reaction force is applied by means of the limiting device, which, in addition to the elastic tension of the locking cord 48, also prevents further swinging of the backrest 5.

[0081] The limiting device 47 includes a release device 49 and a column 50 that cannot rotate relative to the seat body 4, details of which can be found in Figure 8 As seen in the figures, the locking cord 48 is wound multiple times around the column 50 between the release device 49 and the traction device fixing point 51 of the backrest 5 to form a wound body 52. ​​Due to this configuration, if the locking cord 48 is under tensile stress between the release device 49 and the traction device fixing point 51, then the backrest 5 will swing to its maximum extent. This swing limit can be eliminated or amplified by releasing an additional length of the locking cord 48 by means of the release device 49, and this elimination or amplification is carried out for such a long time that the swing of the backrest 5 proceeds to the point that the locking cord 48 sliding on the column 50 is once again under tensile stress. Although not shown in detail in the figures, the release device 49 here is a mechanical locking device that includes a locking pawl engaged in a locking wheel, by which an additional length of the locking cord 48 can be released and further release of the locking cord 48 is prevented when the backrest 5 reaches its swing limit.

[0082] Then and refer to Figure 9 This describes another embodiment of the method according to the present invention, and is carried out by means of including Figure 7 The vehicle 1 with seat 2 shown will be described. Figure 9 The method shown in the flowchart includes steps 53 to 57.

[0083] In the first step 53, similar to step 19 of the first embodiment of the method according to the invention, acceleration information 33 is determined, wherein details regarding acceleration information 33 refer to the first embodiment. Therefore, in this second embodiment, unlike the first embodiment, the determination of occupant information 25 is not performed. Therefore, the process is performed independently of the weight and height of the occupant 3. Figure 9 The method of explanation.

[0084] In the next step 54, it is checked whether the trigger condition is met. If the acceleration information 33 indicates that the absolute value of the current acceleration of vehicle 1 exceeds the preset acceleration limit, thus maximizing the probability of a collision involving vehicle 1, then the trigger condition is met. If the trigger condition is not met, the process returns to step 53 to continue, in which the acceleration information 33 is re-detected and updated.

[0085] If the triggering condition is met, the method continues in step 55. In this step, the side airbag 15 is inflated. Additionally, an extra length segment of the locking rope 48 is released via the restraint device 47, wherein the length of this extra length segment depends on... Figure 10 The characteristic curve shown is 58. Regarding... Figure 10 The coordinate system shown has the horizontal axis 41 representing the current acceleration of vehicle 1, and the vertical axis 59 representing the length of the released segment of the locking rope 48. The dashed line 43 indicates the acceleration limit, which triggers the condition when the acceleration limit is exceeded.

[0086] The following describes the beneficial effect of limiting the acceleration-related forward swing motion of the backrest 5. Assume a very tall and heavy occupant 3 is seated in seat 2. In the event of a collision, the occupant's inertial force is transmitted to the backrest 5 via seatbelt devices 7 and 8, causing the backrest 5 to swing forward. Before reaching the swing limit, a corresponding reaction force is generated based on the plastic and / or elastic deformation of the backrest 5. Unlike the case where the forward swing motion is not limited, the maximum swing of the backrest 5 (where the occupant contacts the dashboard of the vehicle 1) is reached much earlier or at a much smaller acceleration compared to the case of a shorter and lighter occupant.

[0087] according to Figure 10As shown in characteristic curve 58, the length of the released segment of the locking rope 48 and consequently the maximum possible swing distance of the backrest 48 exemplarily increase linearly with increasing acceleration. This increase continues until the maximum acceleration, represented by the dashed line 60, is reached. The maximum acceleration is such that a control occupant with a preset weight and height would come into contact with the dashboard of the vehicle 1 due to the elastic and / or plastic restoring action of the backrest 5, which is not restricted by the restraint device 47. Therefore, the restraint device 47 prevents a occupant 3, who is taller and heavier than the control occupant, from impacting the dashboard at a lower acceleration value.

[0088] During step 55, acceleration information 33 is continuously updated, while in parallel, a stop condition is checked within the scope of step 56. The stop condition is met once the acceleration of vehicle 1 drops below the acceleration limit indicated by the dashed line 43. If this is not the case, steps 55 and 56 are re-executed with continuous detection and therefore updating of acceleration information 33. If the stop condition is met, the method terminates within the scope of the final step 57 and restarts in step 53 if necessary.

Claims

1. A method for protecting occupants (3) in a motor vehicle (1) in the event of a collision, wherein, The motor vehicle (1) has a seat (2) comprising a seat body (4) forming a seat surface and a backrest (5) connected to the seat body (4). In the event of a collision, the inertial force acting on the occupant (3) is transmitted to the backrest (5) via seatbelt devices (7, 8), causing the backrest to swing forward relative to the seat body (4) against the restoring action of elastic and / or plastic deformation of at least one portion of the backrest (5). - A force is generated by a force generator (35) and transmitted to the backrest (5), which reacts to the forward swing, and / or -The maximum possible swing distance of the backrest (5) is limited by a limiting device. This ensures that, given a preset reference acceleration, the deviation between the actual swing distance of the backrest (5) and the preset reference swing distance is minimized.

2. The method according to claim 1, characterized in that, Acceleration information (33) related to the current acceleration of the motor vehicle (1) is determined by using an acceleration sensor, and a limit on the possible maximum sway distance and / or the force is preset based on the acceleration information (33).

3. The method according to claim 2, characterized in that, A characteristic curve (44, 45) is preset to describe the relationship between the current acceleration of the motor vehicle (1) and the force and / or the possible maximum sway distance, and the force and / or the preset limit on the possible maximum sway distance are generated by means of the characteristic curve.

4. The method according to any one of claims 1 to 3, characterized in that, Within the scope of the vehicle controller (26), there is occupant information (25) describing the weight and / or height of the occupant (3), which is invoked and / or determined by means of a sensor (27), wherein the force and / or limit on the possible maximum sway distance are preset based on the occupant information (25).

5. The method according to any one of claims 1 to 3, characterized in that, When the force acting on the forward swing is generated by the force generator (35) and transmitted to the backrest (5), the magnitude of the force is reduced when or after the maximum swing distance of the backrest (5) is reached.

6. The method according to claim 5, characterized in that, When or after the maximum swing distance of the backrest (5) is reached, the magnitude of the force is set to zero.

7. A motor vehicle comprising at least one seat (2), the seat having a seat body (4) forming a seat surface and a backrest (5) connected to the seat body (4), wherein, In the event of a collision, the inertial force acting on the occupant (3) can be transmitted to the backrest (5) via at least one seatbelt device (7, 8), causing the backrest to swing forward relative to the seat body (4) against the restoring action of elastic and / or plastic deformation of at least one portion of the backrest (5), wherein the motor vehicle (1) has a control device (24) designed to drive the force generator (35) and / or restraining device of the motor vehicle (1) in such a way that: - The reaction force on the forward swing can be generated by the force generator (35) and can be transmitted to the backrest (5), and / or -The maximum possible swing distance of the backrest (5) can be limited by the limiting device. This ensures that, given a preset reference acceleration, the deviation between the actual swing distance of the backrest (5) and the preset reference swing distance is minimized.

8. The motor vehicle according to claim 7, characterized in that, In cases where the reaction force acting on the forward swing can be generated and transmitted to the backrest (5) by means of a force generator (35), the force generator (35) is an electromechanical actuator or includes an electromechanical actuator, or the force generator (35) is or includes a damping element.

9. The motor vehicle according to claim 8, characterized in that, The damping element includes a damping fluid.

10. The motor vehicle according to any one of claims 7 to 9, characterized in that, In cases where the force acting on the forward swing can be generated by the force generator (35) and transmitted to the backrest (5), the force generator (35) is connected to the backrest via the pulling device (36) in order to transmit the pulling force generated by the force generator (35) to the backrest (5).

11. The motor vehicle according to claim 10, characterized in that, The pulling device (36) that is connected to the force generator (35) on one side and fixed to the backrest (5) on the other side is a rope or strap.

12. The motor vehicle according to claim 11, characterized in that, The pull rope is a metal pull rope.

13. The motor vehicle according to claim 10, characterized in that, The traction device (36) is guided around at least one steering roller (39) fixed to the seat body (4) or backrest (5).

14. The motor vehicle according to claim 13, characterized in that, The steering roller (39) is fixed to the seat body (4) or backrest (5) in a rotatable manner.

15. The motor vehicle according to any one of claims 7 to 9, characterized in that, When the maximum possible swing distance of the backrest (5) can be limited by a limiting device, the limiting device for limiting the maximum possible swing distance of the backrest (5) is connected to the backrest (5) by a locking rope.

16. The motor vehicle according to claim 15, characterized in that, The locking rope is a metal locking rope.

17. The motor vehicle according to claim 15, characterized in that, The limiting device has a release device and a column that cannot be rotated relative to it, wherein the locking rope is wound around the column between the release device and the locking rope fixing point of the backrest (5), wherein an additional length of the locking rope can be released by the release device.

18. The motor vehicle according to claim 17, characterized in that, The locking rope was wrapped around the column multiple times.

19. The motor vehicle according to claim 17, characterized in that, With the aid of an acceleration sensor, acceleration information (33) related to the current acceleration of the motor vehicle (1) can be determined, wherein the control device (24) is designed to drive the release device so that an additional length of the locking rope is released in relation to the length of the acceleration information (33).

20. The motor vehicle according to any one of claims 7 to 9, characterized in that, Within the scope of the vehicle controller (26), there is occupant information (25) describing the weight and / or height of the occupant (3), which can be accessed, and / or the occupant information (25) describing the weight and / or height of the occupant (3) can be determined by a sensor (27), wherein the control device (24) is designed to preset the force and / or limit the possible maximum swing distance based on the occupant information (25).

21. The motor vehicle according to claim 20, characterized in that, The sensor (27) is a weight sensor (28) arranged in or on the seat body (4), and / or an optical sensor (31) for detecting image data of the passenger compartment (29) and / or environment (30) of the motor vehicle (1), and / or a fingerprint sensor (32) for detecting the fingerprints of the occupant (3).

22. The motor vehicle according to any one of claims 7 to 9, characterized in that, The seat belt device (7, 8) is a three-point seat belt device (9) or a four-point seat belt device or an airbag seat belt device (14), and at least one airbag of the seat (2) is connected to the backrest (5) by means of the airbag seat belt device.

23. The motor vehicle according to claim 22, characterized in that, The airbag is a side airbag (15).

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