Method for controlling restraint components in a vehicle

Abstract

The invention relates to a method for controlling restraint components (R) of an occupant restraint system of a vehicle (1), the restraint components being assigned to an occupant (2) on a vehicle seat (3) having an integrated seat belt device, with a distinction being made by means of a control unit of the occupant restraint system between an upright position and a reclining position of a seat back (3.2) of the vehicle seat (3). According to the invention, at least when the reclining position of the seat back (3.2) is detected, the individual restraint components (R) are activated in a time-controlled manner depending on - a detected distance of the occupant (2) from at least one restraint component (R), - a determined class of the occupant (2) on the vehicle seat (3), - a determined type of collision, and - a severity of the collision.

Description

[0001] Method for controlling restraint components in a vehicle

[0002] The invention relates to a method for controlling restraint components of an occupant restraint system of a vehicle assigned to an occupant on a vehicle seat with integrated safety belt device, wherein a control unit of the occupant restraint system distinguishes between an upright position and a reclining position of a seat back of the vehicle seat.

[0003] From EP 1 160 134 A1, a method for operating an occupant restraint system is known, wherein the method provides for limiting the restraint force exerted on an occupant via a seat belt. Depending on predefined parameters, the restraint level is switched from a relatively higher to a relatively lower level when a seat belt force limiter is activated. The seat belt force limiter is activated after reaching a predetermined occupant forward displacement and only after a predefined airbag inflation time, if a crash intensity and an occupant weight below a predetermined threshold are detected.

[0004] The invention is based on the objective of providing a method for controlling occupant restraint devices of an occupant restraint system of a vehicle.

[0005] The problem is solved according to the invention by a method which has the features specified in claim 1.

[0006] Advantageous embodiments of the invention are the subject of the dependent claims.

[0007] A method for controlling restraint components of an occupant restraint system of a vehicle assigned to an occupant on a vehicle seat with an integrated seat belt device, wherein a control unit of the occupant restraint system distinguishes between an upright position and a reclining position of the vehicle seat backrest. According to the invention, it is provided that, at least when the reclining position of the seat backrest is detected, the individual restraint components are controlled depending on

[0008] - a measured distance between the occupant and at least one restraint component,

[0009] - a determined occupant class of the occupant in the vehicle seat,

[0010] - a determined collision type and

[0011] - can be activated based on the severity of a collision and controlled over time.

[0012] By applying this method, the forces acting on the occupant in a collision, especially when the seat back is in a reclining position, can be significantly and specifically reduced. In particular, the occupant class is taken into account; that is, it is determined whether the occupant is, for example, a tall man, a short woman, a child, or a toddler. Based on the determined occupant class, the measured distance, the type and severity of the collision, the individual restraint components of the restraint system are then controlled and activated to increase the occupant's protection against injury.

[0013] In one implementation, after a predetermined time interval following a collision, a seatbelt pretensioner is activated to tighten the strap of the integrated seatbelt system, acting as a restraint component. For example, activation occurs between 8 ms and 25 ms after the collision, whereby the occupant is secured to the vehicle seat by the tightening of the strap and thus optimally participates in the overall deceleration of the vehicle due to the collision, thereby reducing the forces acting on the occupant.

[0014] Another embodiment of the procedure provides that, after a predetermined time period following the activation of the belt tensioner, an end-fit tensioner of the seat belt device is activated as a restraint component. Following a further time period after the activation of the end-fit tensioner, a belt force limiter is activated as a restraint component to limit the belt force acting on the occupant. The belt tension is increased by engaging the end-fit tensioner to optimize the occupant's connection to their vehicle seat. The activation of the belt force limiter restricts the belt force acting on the occupant due to the belt tension, thereby reducing the risk of injury potentially resulting from the belt tension, such as crushing in the chest and / or pelvic area of ​​the occupant.

[0015] In one possible implementation, a switching point for activating the seatbelt force limiter is predetermined depending on the severity and type of collision, the occupant class, and the detected distance between the occupant and an airbag, particularly a driver's or passenger's airbag, as a restraint component. Essentially, all parameters relevant to limiting the seatbelt force are taken into account to maintain the occupant's connection to the vehicle seat while still adjusting the belt force exerted on the occupant, thus reducing the risk of injury to the occupant from the belt and its tensioning.

[0016] In one design, after activation of the seatbelt pretensioner, the first stage of an airbag assigned to the occupant is activated and deployed as a restraint component. The airbag, particularly the driver's airbag, typically deploys from the steering wheel hub or an area of ​​the instrument panel, while the passenger airbag typically deploys from an area of ​​the instrument panel located in front of the passenger. The airbag is activated with a first stage, causing it to deploy from a compartment containing an airbag module and assume its operational position.If the distance between the airbag and the occupants is relatively small despite the seat back being in a reclining position, for example because the vehicle seat is positioned relatively close to the steering wheel or the instrument panel, the airbag may be positioned sufficiently well in the first airbag stage in relation to the occupant to reduce the risk of injury.

[0017] If, in a further iteration of the procedure, it is determined that the distance between the occupant and the airbag exceeds a predetermined threshold, at least a second airbag stage is activated and deployed after a predetermined time interval following the deployment of the first airbag stage, for example, the driver's or passenger's airbag. Specifically, the airbag is a so-called depth-adaptive airbag, which can deploy in multiple stages towards the occupant to reduce the distance, thus ensuring protection against injury even at a comparatively large distance.

[0018] Furthermore, in one embodiment of the procedure, a pelvis airbag is activated and deployed simultaneously with the activation of the seatbelt tensioning system. Specifically, by activating the pelvis airbag, which is integrated into the seat cushion of the vehicle seat, the occupant's pelvic and hip area is protected from injury, and the risk of submarining (slipping under the lap belt) is largely avoided.

[0019] In another version, a seat cushion lowering device is activated as a restraint component after a predetermined time interval following activation of the end-of-seat tensioner and / or after activation of the pelvic airbag. For example, the seat cushion lowering device can reduce the risk of lumbar spine injuries.

[0020] Furthermore, one design provides that, simultaneously with the activation of the first stage of the airbag, at least the first stage of an occupant's knee airbag is activated as a restraint component. The knee airbag further reduces the risk of the occupant sliding under the lap belt, and in particular, it essentially prevents the occupant's shins from striking the instrument panel, thus significantly reducing the risk of bruising and / or fractures of the shins.

[0021] In one embodiment of the method, at the time of activation of the belt force limiter, an outlet opening of the airbag is adaptively opened, so that the degree of hardness of the gas-filled airbag, positioned in its effective position, is reduced, and thus kinetic energy in the event of an impact, in particular of the occupant's head, on the airbag is absorbed by means of the airbag, since the gas can escape from the airbag via the outlet opening due to the impact.

[0022] Exemplary embodiments of the invention are explained in more detail below with reference to the drawings. These show:

[0023] Fig. 1 schematically shows a section of a vehicle with one occupant on a

[0024] Vehicle seat with a seat back adjusted to a reclining position,

[0025] Fig. 2 schematically shows a section of the vehicle with the occupant and a number of restraint components of an occupant restraint system of the vehicle and

[0026] Fig. 3 schematically shows a temporal sequence of activation of restraint components of the occupant restraint system from a collision point.

[0027] Corresponding parts are marked with the same reference symbols in all figures.

[0028] Figure 1 shows a section of a vehicle 1 with an occupant 2 on a vehicle seat 3, which is a driver's seat of the vehicle 1.

[0029] Figure 2 shows a section of the vehicle 1 with the occupant 2 on the vehicle seat 3 and a number of restraint components R of an occupant restraint system of the vehicle 1, and Figure 3 shows a temporal sequence of a control and activation of restraint components R of the occupant restraint device.

[0030] The vehicle seat 3 comprises a seat cushion 3.1, which forms a seating surface for the occupant 2, a seat backrest 3.2, which is positioned in a reclining position, a so-called Relaxed Seating Position, according to Figure 1, and a headrest 3.3.

[0031] For example, vehicle 1 operates in fully automated, i.e., autonomous, ferry mode, particularly at the highest level of automation, so that the driving task is performed entirely by vehicle 1 itself. The occupant 2, in particular the driver, of vehicle 1 can thus engage in another activity, such as adjusting the seat backrest 3.2 to a reclining position and allowing occupant 2 to relax.

[0032] If occupant 2 is lying on his vehicle seat 3 and vehicle 1 collides head-on with an object, for example another vehicle not shown in detail, occupant 2 faces risks of injury, in particular to the spine and pelvic and hip area 2.1 of occupant 2, which do not essentially exist if occupant 2 is in an upright sitting position.

[0033] In the reclining position of the seat back 3.2, new injury patterns in the area of ​​the spine and pelvis can therefore occur in the event of a collision of the vehicle 1, whereby there is an increased risk of injury in the case of known injury patterns in the head area 2.2, in the neck area 2.3, in the chest area 2.4 and in the pelvic area 2.1, for example due to the occupant 2 sliding under a lap belt 4.1 of a belt strap 4 of a safety belt device assigned to the occupant 2.

[0034] To at least reduce the risk of injury to the occupant 2 lying on vehicle seat 3, the restraint components R of the occupant restraint system are designed accordingly, and a method for controlling the restraint components R is described below. The occupant restraint system is assigned to vehicle seat 3 and, in particular, to the occupant 2 lying on vehicle seat 3. Such an occupant restraint system can also be provided for a front passenger in a front passenger seat of vehicle 1, whereby a distinction is made between an upright position of the seat back 3.2 and a reclined position of the seat back 3.2 of vehicle seat 3 for controlling the restraint components R.

[0035] The occupant restraint system comprises, as controllable and activatable restraint components R, an airbag RI, in particular a depth-adaptive driver's airbag, hereinafter referred to as driver airbag RI, with an adaptively deployable discharge opening A, an optionally depth-adaptive knee airbag R2, a pelvis airbag R3, and the seat belt assembly, which is integrated into the vehicle seat 3. The vehicle seat 3 is thus designed as an integral seat with integrated seat belts. The seat belt assembly is coupled to a controllable and activatable belt tensioner R4, an end-fit tensioner R5, and a belt force limiter R6, for example, for the lap belt 4.1. Such a belt force limiter R6, for example, in the form of a torsion bar, can be integrated into the belt tensioner R4 and / or the end-fit tensioner R5.Furthermore, the occupant restraint system includes as restraint components R a footwell airbag R7 and a seat cushion lowering device R8, in particular a semi-active seat cushion lowering device R8.

[0036] In particular, the occupant 2 lying down faces an increased risk of injury in the event of a frontal collision with vehicle 1, because the distance between occupant 2 and, for example, a conventional driver airbag RI, is greater in comparison, and the conventional driver airbag RI can therefore only provide limited protection against injury to occupant 2.

[0037] For this reason, at least the driver's airbag (RI) is designed to be depth-adaptive, thus bridging this increased distance to occupant 2 in the reclining position and specifically adjusting the airbag depth. The firmness of the driver's airbag (RI), particularly in relation to the classified occupant 2, can be adjusted using the adaptively releasable discharge opening (A).

[0038] In one possible version of the knee airbag R2, it is enlarged and depth-adaptive, so that knee and / or shin restraint of occupant 2 is possible, even if occupant 2 is sitting or lying comparatively far away from the knee airbag R2.

[0039] By means of the belt tensioner R4 and the end fitting tensioner R5, the belt strap 4 fastened by the occupant 2 is tightened, thus reducing belt slack, ensuring the belt strap 4 lies taut against the occupant 2's body, and allowing the occupant 2 to participate in the overall deceleration of the vehicle 1 relatively early in the event of a collision. The belt force limiter R6 limits the belt force acting on the occupant 2 due to the tightening of the belt strap 4, thereby reducing the risk of injury caused by this tightening, particularly in the pelvic region 2.1 and the chest region 2.4 of the occupant 2. Specifically, the belt force limiter R6 reduces the risk of fractures of the pelvic bones, which can occur due to reduced support of the lower extremities of the occupant 2 in the lying position.

[0040] By means of the activated and deployed footwell airbag R7, the legs 2.5 of the occupant 2 are protected in the event of a collision of the vehicle 1, in particular with regard to an impact on vehicle parts which, for example, deform as a result of the collision and penetrate into a vehicle interior.

[0041] The seat cushion lowering device R8 is specifically designed to cause the seat cushion 3.1 of the vehicle seat 3 to pivot about a pivot axis arranged parallel to the vehicle's transverse axis. The seat backrest 3.2 may also pivot along with the seat cushion, thus positioning it in a more upright position. Lowering the seat cushion reduces collision-related stress on the lumbar spine of the occupant 2.

[0042] In one embodiment of the occupant restraint system, a seat cushion airbag (not shown in detail) represents a further restraint component R, by means of which the risk of sliding under the lap belt 4.1 of the belt 4 and the loads on the lumbar spine can be reduced.

[0043] The occupant restraint system essentially comprises known restraint components R, which are used to address new injury patterns relating to the spine and pelvic region 2.1 due to the occupant's reclining position on the vehicle seat 3. The restraint components R are activated in a time-defined sequence to reduce the risk of injury to the occupant 2. Furthermore, the occupant restraint system is designed to protect the occupant 2 on the vehicle seat 3 in two significantly different seating positions for each occupant 2 size, i.e., both when the vehicle seat 3 is in the reclining position and when the seat back 3.2 is in an upright position.For this purpose, a switching logic is used by means of which the restraint components R are controlled depending on determined information regarding collision severity, occupant class, and the distance of the occupant 2 to at least the driver airbag RI and the knee airbag R2. In particular, this distance between the occupant 2 and especially the driver airbag RI depends on the position of the vehicle seat 3 along a longitudinal axis of the vehicle, the inclination of the seat cushion 3.1, and the inclination of the seat backrest 3.2 of the vehicle seat 3.

[0044] In particular, a control unit of the occupant restraint system distinguishes between an upright position and a reclining position of the seat back 3.2 of the vehicle seat 3, whereby the distance between the occupant 2 and in particular the driver airbag RI is determined on the basis of signals detected by a suitable sensor system, in particular on the basis of image signals detected by an interior monitoring system, in particular a camera system.

[0045] Furthermore, to increase the protection of occupant 2 from injury, occupant 2 is classified based on occupancy type, weight, and height. This information is also determined using image signals captured by the interior monitoring system, thus assigning occupant 2 to an occupant class. A distinction is made in particular between small, medium, and large occupants, as well as children and infants.

[0046] The severity and type of collision, i.e., whether it is a frontal collision, etc., are determined in particular based on signals recorded by a collision sensor system, which transmits the recorded signals to the control unit of the occupant restraint system for evaluation and processing.

[0047] Figure 3 shows, in an exemplary and highly simplified manner, a temporal sequence of the activation of the restraint components R of the occupant restraint system from a collision time to.

[0048] At an initial time point ti, for example 8 ms to 25 ms, particularly 10 ms to 15 ms, after the collision time to, the belt tensioner R4 is controlled and activated, so that the belt strap 4 in contact with the body of occupant 2 is tightened, thus reducing the belt slack and the resulting forward displacement path of occupant 2. Occupant 2 is secured to the vehicle seat 3 by means of the tightened belt strap 4, so that occupant 2 participates in the overall deceleration of the vehicle 1 relatively early.

[0049] At a second point in time tz, for example 10 ms to 25 ms after the collision time to, a first airbag stage of the driver airbag RI and the knee airbag R2 is activated, and the pelvis airbag R3 is also activated.

[0050] Furthermore, at the second time point t2, the footwell airbag R7, which may be present in the footwell, is activated. The activation of the driver airbag RI, the knee airbag R2, and the footwell airbag R7 extends to a third time point t3. After, for example, 5 ms, at a fourth time point t4, a second airbag stage of the driver airbag RI is activated, with the end-of-travel airbag tensioner R5 being activated at approximately the same time.

[0051] In particular, in addition to the second airbag stage of the driver airbag (RI), the depth adaptation (T) is activated, whereby a third airbag stage is activated depending at least on the determined occupant distance. In this case, the driver airbag (RI) is pressurized again with gas to achieve a larger airbag volume. The second and / or third airbag stage can be activated simultaneously with the depth adaptation (T), or, depending on the design of the driver airbag (RI), after a predetermined time period following activation of the first airbag stage, or by means of a separately defined ignition threshold.

[0052] The activation of the depth adaptivity T of the driver airbag RI and, if applicable, the knee airbag R2, only occurs when the vehicle seat 3 is detected to be in a reclining position and, in particular, depending on the distance between the occupant 2 and the driver airbag RI. If it is determined that the distance between the occupant 2 and the driver airbag RI exceeds a predefined threshold, the depth adaptivity T, in particular the second airbag stage and / or the third airbag stage, is activated at a sixth time point t6.

[0053] At a fifth time point t5, the seat cushion lowering device R8 is activated, but only if the pelvis airbag R3 was activated previously, in particular 40 ms prior, and the belt tensioner R4 and the end fitting tensioner R5 were activated.

[0054] At a seventh point in time t7, the belt force limiter R6 is activated and the discharge opening A of the driver's airbag RI is at least partially released. In particular, the respective activation depends on the position of the vehicle seat 3 in the direction of a longitudinal axis of the vehicle and the inclination of the seat backrest 3.2 of the vehicle seat 3.

[0055] The switching point for releasing the outlet opening A and activating the belt force limiter R6 depends on the severity and type of collision, the occupant class assigned to occupant 2, and the distance between occupant 2 and the driver airbag RI. For example, the belt force limiter R6 is part of the end-tensioner R5 and, upon reaching a predetermined force level, releases a specific extension length of the belt webbing 4 without providing occupant 2 with an unfavorable forward displacement.

[0056] If the collision is a side-on frontal collision, a window airbag is also activated as a further restraint component of the occupant restraint system and positioned in its operational position.

[0057] If the procedure is applied to a passenger seat of vehicle 1 and it is determined from the image signals that a child is in a child seat in the passenger seat, the passenger airbag is deactivated and therefore cannot be triggered.

[0058] The number and characteristics of the restraint components R of the occupant restraint system can vary with respect to the restraint components R described above, including the time points ti to t. nThe activation of the respective restraint component R may vary depending on the detected distance of the occupant 2 to at least the driver airbag RI or a passenger airbag, the determined occupant class of the occupant 2 on the vehicle seat 3, the determined collision type and the collision severity.

[0059] Reference symbol list

[0060] 1 vehicle

[0061] 2 occupants

[0062] 2.1 Pelvic area

[0063] 2.2 Head area

[0064] 2.3 Neck area

[0065] 2.4 Chest area

[0066] 2.5 leg

[0067] 3 vehicle seats

[0068] 3.1 Seat cushions

[0069] 3.2 Seat backrest

[0070] 3.3 Headrest

[0071] 4 webbing

[0072] 4.1 Pelvic belt

[0073] A Outlet opening

[0074] R Retention component

[0075] RI Airbag / Driver's Airbag

[0076] R2 knee airbag

[0077] R3 Pelvis airbag

[0078] R4 seatbelt tensioner

[0079] R5 end fitting tensioner

[0080] R6 belt force limiter

[0081] R7 Footwell Airbag

[0082] R8 seat cushion lowering device

[0083] T depth adaptivity to collision time ti to tn time

Claims

Patent claims 1. Method for controlling restraint components (R) of an occupant restraint system of a vehicle (1) assigned to an occupant (2) on a vehicle seat (3) with integrated seat belt device, wherein a control unit of the occupant restraint system distinguishes between an upright position and a reclining position of a seat back (3.2) of the vehicle seat (3), characterized in that, at least when the reclining position of the seat back (3.2) is detected, the individual restraint components (R) are controlled depending on - a measured distance of the occupant (2) to at least one restraint component (R), - a determined occupant class of the occupant (2) on the vehicle seat (3), - a determined collision type and - can be activated based on the severity of a collision and controlled over time.

2. Method according to claim 1, characterized in that after a predetermined time period following a collision time (to) a belt tensioner (R4) is first activated to tighten an applied belt strap (4) of the safety belt device integrated into the vehicle seat (3) as a restraint component (R).

3. Method according to claim 2, characterized in that after a predetermined time period following the activation of the belt tensioner (R4) an end fitting tensioner (R5) of the safety belt device is activated as a restraint component (R) and after a further time period following the activation of the end fitting tensioner (R5) a belt force limiter (R6) as The restraint component (R) is activated to limit the belt force acting on the occupant (2).

4. Method according to claim 3, characterized in that a switching point for activating the The belt force limiter (R6) is specified depending on the severity of the collision, the type of collision, the occupant class and the detected distance between the occupant (2) and an airbag (RI) as a restraint component (R).

5. Method according to one of claims 2 to 4, characterized in that after activation of the belt tensioner (R4) a first airbag stage of an airbag (RI) assigned to the occupant (2) is activated and triggered as a restraint component (R).

6. Method according to claim 5, characterized in that if the distance between the occupant (2) and the airbag (RI) exceeds a predetermined threshold, at least a second airbag stage is activated and triggered after a predetermined time period following the activation of the first airbag stage of the airbag (RI).

7. Method according to one of claims 2 to 6, characterized in that a pelvis airbag (R3) is activated and triggered as a restraint component (R) simultaneously with the activation of the belt tensioning.

8. Method according to claim 7, characterized in that a seat cushion lowering device (R8) is activated as a restraint component (R) a predetermined time period after the activation of the end fitting tensioner (R5) and / or after the activation of the pelvis airbag (R3).

9. Method according to one of claims 6 to 8, characterized in that at least one first airbag stage of a knee airbag (R2) assigned to the same occupant (2) is activated simultaneously with the activation of the first airbag stage of the airbag (RI) as a restraint component (R).

10. Method according to one of claims 4 to 9, characterized in that at a time (t7) of activation of the The belt force limiter (R6) adaptively opens an outlet opening (A) of the airbag (RI).

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